01.07.2013 Views

chapter 3 - Bentham Science

chapter 3 - Bentham Science

chapter 3 - Bentham Science

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Applications of Spreadsheets in Education<br />

The Amazing Power of a Simple Tool<br />

Edited by<br />

Mark Lau and Stephen Sugden


eBooks End User License Agreement<br />

Please read this license agreement carefully before using this eBook. Your use of this eBook/<strong>chapter</strong> constitutes your agreement<br />

to the terms and conditions set forth in this License Agreement. <strong>Bentham</strong> <strong>Science</strong> Publishers agrees to grant the user of this<br />

eBook/<strong>chapter</strong>, a non-exclusive, nontransferable license to download and use this eBook/<strong>chapter</strong> under the following terms and<br />

conditions:<br />

1. This eBook/<strong>chapter</strong> may be downloaded and used by one user on one computer. The user may make one back-up copy of this<br />

publication to avoid losing it. The user may not give copies of this publication to others, or make it available for others to copy or<br />

download. For a multi-user license contact permission@bentham.org<br />

2. All rights reserved: All content in this publication is copyrighted and <strong>Bentham</strong> <strong>Science</strong> Publishers own the copyright. You may<br />

not copy, reproduce, modify, remove, delete, augment, add to, publish, transmit, sell, resell, create derivative works from, or in<br />

any way exploit any of this publication’s content, in any form by any means, in whole or in part, without the prior written<br />

permission from <strong>Bentham</strong> <strong>Science</strong> Publishers.<br />

3. The user may print one or more copies/pages of this eBook/<strong>chapter</strong> for their personal use. The user may not print pages from<br />

this eBook/<strong>chapter</strong> or the entire printed eBook/<strong>chapter</strong> for general distribution, for promotion, for creating new works, or for<br />

resale. Specific permission must be obtained from the publisher for such requirements. Requests must be sent to the permissions<br />

department at E-mail: permission@bentham.org<br />

4. The unauthorized use or distribution of copyrighted or other proprietary content is illegal and could subject the purchaser to<br />

substantial money damages. The purchaser will be liable for any damage resulting from misuse of this publication or any<br />

violation of this License Agreement, including any infringement of copyrights or proprietary rights.<br />

Warranty Disclaimer: The publisher does not guarantee that the information in this publication is error-free, or warrants that it<br />

will meet the users’ requirements or that the operation of the publication will be uninterrupted or error-free. This publication is<br />

provided "as is" without warranty of any kind, either express or implied or statutory, including, without limitation, implied<br />

warranties of merchantability and fitness for a particular purpose. The entire risk as to the results and performance of this<br />

publication is assumed by the user. In no event will the publisher be liable for any damages, including, without limitation,<br />

incidental and consequential damages and damages for lost data or profits arising out of the use or inability to use the publication.<br />

The entire liability of the publisher shall be limited to the amount actually paid by the user for the eBook or eBook license<br />

agreement.<br />

Limitation of Liability: Under no circumstances shall <strong>Bentham</strong> <strong>Science</strong> Publishers, its staff, editors and authors, be liable for<br />

any special or consequential damages that result from the use of, or the inability to use, the materials in this site.<br />

eBook Product Disclaimer: No responsibility is assumed by <strong>Bentham</strong> <strong>Science</strong> Publishers, its staff or members of the editorial<br />

board for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any<br />

use or operation of any methods, products instruction, advertisements or ideas contained in the publication purchased or read by<br />

the user(s). Any dispute will be governed exclusively by the laws of the U.A.E. and will be settled exclusively by the competent<br />

Court at the city of Dubai, U.A.E.<br />

You (the user) acknowledge that you have read this Agreement, and agree to be bound by its terms and conditions.<br />

Permission for Use of Material and Reproduction<br />

Photocopying Information for Users Outside the USA: <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd. grants authorization for individuals<br />

to photocopy copyright material for private research use, on the sole basis that requests for such use are referred directly to the<br />

requestor's local Reproduction Rights Organization (RRO). The copyright fee is US $25.00 per copy per article exclusive of any<br />

charge or fee levied. In order to contact your local RRO, please contact the International Federation of Reproduction Rights<br />

Organisations (IFRRO), Rue du Prince Royal 87, B-I050 Brussels, Belgium; Tel: +32 2 551 08 99; Fax: +32 2 551 08 95; E-mail:<br />

secretariat@ifrro.org; url: www.ifrro.org This authorization does not extend to any other kind of copying by any means, in any<br />

form, and for any purpose other than private research use.<br />

Photocopying Information for Users in the USA: Authorization to photocopy items for internal or personal use, or the internal<br />

or personal use of specific clients, is granted by <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd. for libraries and other users registered with the<br />

Copyright Clearance Center (CCC) Transactional Reporting Services, provided that the appropriate fee of US $25.00 per copy<br />

per <strong>chapter</strong> is paid directly to Copyright Clearance Center, 222 Rosewood Drive, Danvers MA 01923, USA. Refer also to<br />

www.copyright.com


To my wife Keddy and daughter Helga<br />

for making my mornings brighter and<br />

for lifting my spirit in the face of adversity<br />

Mark Lau<br />

To my sons, Benn and Stephen,<br />

and my grandsons Nikolas and Marko<br />

Stephen Sugden


CONTENTS<br />

Foreword i<br />

Preface ii<br />

Contributors v<br />

CHAPTERS<br />

1. Fault Analysis in Power Systems<br />

Mark A. Lau and Sastry P. Kuruganty<br />

Part I – Engineering<br />

2. Use of Spreadsheets for Analyses in Structural Engineering<br />

Nelson Lam<br />

3. Optimal Control of Dynamical Systems<br />

Mark A. Lau and William E. Singhose<br />

Part II – Mathematics and <strong>Science</strong>s<br />

4. Spreadsheet Conditional Formatting Illuminates Investigations into Modular<br />

Arithmetic<br />

5.<br />

6.<br />

David Miller and Stephen Sugden<br />

Computational Problem Solving in Context:<br />

From Arithmetic Sequences to Polygonal-like Numbers<br />

Sergei Abramovich<br />

Enzyme Kinetics for Novice Learners:<br />

Numerical Simulation in Excel<br />

Scott A. Sinex and Barbara A. Gage<br />

3<br />

18<br />

41<br />

64<br />

84<br />

107


Part III – Management <strong>Science</strong>s<br />

7. Project Management Spreadsheet Gaming Application<br />

Wee Leong Lee<br />

8. Teaching Portfolio Theory in an Equilibrium Setting with the Aid of Spreadsheet<br />

Tools<br />

Clarence C.Y. Kwan<br />

9. Forecasting with Innovation Diffusion Models: An Updated Example from the<br />

Telecommunications Industry 1994-2009<br />

John F. Kros and S. Scott Nadler<br />

10. School Mathematics with Excel<br />

Jan Benacka<br />

Part IV – General Education<br />

11. Graduates’ Use of Technical Software in Financial Services<br />

Timothy Kyng, Leonie Tickle, and Leigh Wood<br />

12. Professional Development in Electricity Markets with Spreadsheet Models<br />

Elliot Tonkes<br />

Subject Index 274<br />

116<br />

140<br />

159<br />

173<br />

241<br />

261


FOREWORD<br />

A little over 30 years have passed since the first spreadsheet, VisiCalc, made its appearance as an<br />

exciting and effective computer tool for accounting and business modeling. In the ensuing years,<br />

educators have increasingly recognized that the spreadsheet has extraordinary potential for other<br />

applications as well. Today, not only are spreadsheets, as exemplified by Microsoft Excel, among<br />

the most widely-used modeling and mathematical tools of the workplace, but they also find abundant<br />

use in diverse areas of education. In addition to business-related areas, usage flourishes in<br />

mathematics, the natural and social sciences, engineering, and many other areas. The spreadsheet’s<br />

natural, approachable tabular format and its operations that are acquired readily make it accessible<br />

to students. With their formidable graphics features, user tools, and programming capabilities,<br />

spreadsheets are effective tools for teachers, students, and researchers.<br />

Yet, even today the value of spreadsheets in education is not always fully recognized. To address<br />

that situation, this book supplies readers with a substantial variety of educational applications for<br />

spreadsheets, from fields such as engineering, mathematics, science, and business. The diverse<br />

applications show two principal ways of using a spreadsheet. First, it is a natural tool for designing<br />

applications directly from first principles and then experimenting with the resulting model. Second,<br />

it provides an accessible way to implement models and algorithms that are first derived analytically<br />

by traditional methods. In either way, a major advantage of the spreadsheet approach is to make<br />

more topics accessible to students that may otherwise be too advanced for them.<br />

Using the book’s applications, instructors and students can investigate and interrogate the various<br />

models in the traditional “What if ...?” spreadsheet manner by varying its parameters values.<br />

They also can visualize the results in both the attractive graphs and the well-designed spreadsheet<br />

displays that are presented.<br />

The examples provided include a number that are of a sophisticated nature, showing how<br />

spreadsheet usage can be extended to more complex problems. Several examples examine models<br />

that use a difference equation approach that is natural for the spreadsheet medium to implement<br />

numerical analysis algorithms for topics coming from calculus, linear algebra, and ordinary and<br />

partial differential equations.<br />

Throughout the book readers also will encounter the use of powerful tools provided on a spreadsheet<br />

such as Excel, including built-in and user-designed functions, matrix operations, a solver,<br />

sliders, and VBA programming. Finally, in addition to providing a wealth of useful examples, each<br />

<strong>chapter</strong> contains numerous references and a list of other related topics and problems to pursue, as<br />

well as ways in which spreadsheet usage can be incorporated into the classroom, assignments, and<br />

group projects. This book represents a very useful contribution to the literature on the educational<br />

uses of spreadsheets.<br />

Deane Arganbright<br />

Martin, Tennessee, USA<br />

and Divine Word University, Papua New Guinea<br />

i


ii<br />

PREFACE<br />

This e-book is devoted to the use of spreadsheets in the service of education in a broad spectrum<br />

of disciplines: science, mathematics, engineering, business, and general education. The effort is<br />

aimed at collecting the works of prominent researchers and educators that make use of spreadsheets<br />

as a means to communicate concepts with high educational value.<br />

Spreadsheets have been around since the late 70s. They were initially conceived as office<br />

productivity tools, most notably in accounting applications. Over time, spreadsheets evolved to incorporate<br />

a wealth of functions to appeal to the scientific community. Applications of spreadsheets<br />

in different branches of science and engineering are continually being reported in many scholarly<br />

journals.<br />

In recent years, a shift in learning paradigms towards a more constructivist education has incited<br />

researchers and educators to find new approaches to education in science, mathematics, and<br />

engineering. This trend is not confined to the USA only, but it seems that it is more widespread<br />

around the globe. It is in this context, that applications of spreadsheets in education, from primary<br />

to university levels, are gaining marked prominence, as evidenced by the number of journal<br />

publications and presentations at technical conferences.<br />

This e-book brings some of the most recent applications of spreadsheets in education and research<br />

to the fore. We assume that the reader is already familiar with the basics of electronic<br />

spreadsheets. To offer the reader a broad overview of the diversity of applications, carefully chosen<br />

examples from different areas have been included. Applications have been organized in four parts,<br />

each containing three <strong>chapter</strong>s:<br />

• Part I: Engineering<br />

Chapter 1 presents fault analysis in power systems, a common topic in power system courses.<br />

Symmetrical and unsymmetrical short circuit currents are computed using a spreadsheet. The<br />

determination of these currents provides valuable information for selecting the appropriate<br />

protection equipment in a power system.<br />

Chapter 2 shows how to implement spreadsheets for structural analysis. The topic is relevant<br />

to many branches of engineering, namely, civil, mechanical, aerospace, and structural<br />

engineering. Spreadsheet models for analyzing beams, walls, frames, and multi-degree-offreedom<br />

systems are presented.<br />

Chapter 3 discusses optimal control of dynamical systems. The minimum principle of Pontryagin<br />

and the numerical solution of differential equations are illustrated with spreadsheets.<br />

In addition, an interesting example motivated by research (control of a flexible structure via<br />

command shaping) is presented in this <strong>chapter</strong>.


• Part II: Mathematics and <strong>Science</strong>s<br />

Chapter 4 illustrates modular arithmetic, a topic that is relevant to mathematicians and computer<br />

scientists. This <strong>chapter</strong> makes use of the conditional formatting of spreadsheets to<br />

reveal interesting patterns in modular arithmetic.<br />

Chapter 5 presents computational problem solving in context. In this <strong>chapter</strong>, some amusing<br />

problems involving difference equations, number sequences, and polygon-like numbers are<br />

solved with the help of spreadsheets.<br />

Chapter 6 introduces enzyme kinetics to chemistry, biology, and biochemistry students. This<br />

<strong>chapter</strong> includes the kinetics of enzyme reactions, linear and non-linear regression analyses,<br />

experimental error, and the effects of inhibitors.<br />

• Part III: Management <strong>Science</strong>s<br />

Chapter 7 describes a project management gaming application. The project management<br />

game is designed as a teaching tool to allow players to experience project management in an<br />

interactive and fun atmosphere. The game exposes players to project planning, budgeting,<br />

resource allocation, decision making, and many other aspects of IT projects in a very realistic<br />

manner.<br />

Chapter 8 introduces mean-variance portfolio theory, which is part of the core curriculum<br />

of modern finance in business education. In particular, this <strong>chapter</strong> presents an asset pricing<br />

model in an equilibrium setting. Several spreadsheet features in matrix operations are used<br />

to illustrate the computational task involved.<br />

Chapter 9 presents a research study on the innovation diffusion model and the life cycle of a<br />

high technology product applied to the sales of modems from 1994–2009, including successive<br />

generations of modems: 14.4k, 28.8k, 56k, broadband less than 3.6Mbps, and broadband<br />

greater than 3.6Mbps. The model is used by managers to understand the development of new<br />

products and their life cycle.<br />

• Part IV: General Education<br />

Chapter 10 exploits the graphical capabilities of spreadsheets to enhance the teaching and<br />

learning of school mathematics. Topics presented in this <strong>chapter</strong> include introductory calculus,<br />

functions, linear algebra, conics, and stereometry.<br />

Chapter 11 reports a research study on the use of technical software, including spreadsheets,<br />

by graduates of actuarial studies programs in Australia. The <strong>chapter</strong> suggests some implications<br />

for universities wishing to design curriculum to prepare students for careers in the<br />

financial services industry.<br />

Chapter 12 presents a case study illustrating the physical dispatch algorithm used by Australia’s<br />

electricity market operator (AEMO) to determine which power plants to dispatch into<br />

the grid and the resultant electricity spot price. The spreadsheet model presented in this<br />

<strong>chapter</strong> is used in professional development workshops.<br />

Some of these applications make use of Visual Basic for Applications (VBA), a versatile computer<br />

language that further expands the functionality of spreadsheets.<br />

iii


iv<br />

The <strong>chapter</strong>s contained herein were contributed by prominent researchers and educators who<br />

made creative use of spreadsheets as a research, teaching, and/or learning tool. The reader can<br />

download the spreadsheet models presented in this e-book from the publisher’s website. The<br />

breadth of applications will provide the reader with a fresh look at the amazing power and the<br />

simplicity of spreadsheets and the VBA programming environment. We hope that the material included<br />

in this e-book will inspire readers to devise their own applications and enhance their teaching<br />

and/or learning experience, and share our passion for spreadsheets.<br />

Acknowledgements<br />

First and foremost, we wish to acknowledge our great debt to our contributors for sharing their<br />

expertise. We are grateful to the following people for their valuable comments and diligence in<br />

reviewing this e-book: John Baker (Natural Maths, Australia), Oscar Chavez (Mathematics Education<br />

Program, University of Missouri, USA), Greg Cranitch (School of Information Technology,<br />

Bond University, Australia), Marjorie Darrah (Department of Mathematics, West Virginia University,<br />

USA), Neville de Mestre (Emeritus Professor, School of Information Technology, Bond University,<br />

Australia), Therese Donovan (Vermont Cooperative Fish and Wildlife Research Unit, University<br />

of Vermont, USA), Adrian Gepp (School of Business, Bond University, Australia), Kieran<br />

Lim (School of Biological and Chemical <strong>Science</strong>s, Deakin University, Australia), Thomas Overbye<br />

(Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign,<br />

USA), Malcolm Peck (Managing Director, The Carnot Group, Australia), Warren Richards (Head<br />

of Department of Mathematics, Moreton Bay College, Australia), Vladimir Romanenko (North<br />

Western Institute of Printing, St. Petersburg State University of Technology and Design, Russia),<br />

Geoff Smith (Department of Mathematics, University of Technology, Sydney, Australia), Michael<br />

Steele (Faculty of Business, Division of Economics and Statistics, Bond University, Australia), and<br />

to the anonymous peer reviewers appointed by <strong>Bentham</strong> <strong>Science</strong> Publishers. We also want to thank<br />

Salma Sarfaraz and Hina Wahaj of <strong>Bentham</strong> for their assistance in making this project a success.<br />

Mark Lau<br />

Universidad del Turabo, Puerto Rico, USA<br />

mlau@suagm.edu<br />

Stephen Sugden<br />

Bond University, Queensland, Australia<br />

ssugden@bond.edu.au<br />

August 2011


CONTRIBUTORS<br />

Sergei Abramovich<br />

Department of Curriculum and Instruction<br />

State University of New York at Potsdam, Potsdam, New York, USA<br />

Jan Benacka<br />

Faculty of Natural <strong>Science</strong>s<br />

Constantine the Philosopher University, Nitra, Slovakia<br />

Barbara A. Gage<br />

Department of Physical <strong>Science</strong>s and Engineerin<br />

Prince George’s Community College, Largo, Maryland, USA<br />

John F. Kros<br />

Department of Marketing and Supply Management<br />

East Carolina University, Greenville, North Carolina, USA<br />

Sastry P. Kuruganty<br />

Department of Electrical and Computer Engineering<br />

Universidad del Turabo, Gurabo, Puerto Rico, USA<br />

Clarence C.Y. Kwan<br />

DeGroote School of Business<br />

McMaster University, Hamilton, Ontario, Canada<br />

Timothy Kyng<br />

Department of Actuarial Studies<br />

Macquarie University, New South Wales, Australia<br />

Nelson Lam<br />

Department of Civil and Environmental Engineering<br />

University of Melbourne, Victoria, Australia<br />

Mark A. Lau<br />

Department of Electrical and Computer Engineering<br />

Universidad del Turabo, Gurabo, Puerto Rico, USA<br />

v


vi<br />

Wee Leong Lee<br />

School of Information Systems<br />

Singapore Management University, Singapore<br />

David Miller<br />

Department of Mathematics<br />

West Virginia University, Morgantown, West Virginia, USA<br />

S. Scott Nadler<br />

College of Business<br />

University of Central Arkansas, Conway, Arkansas, USA<br />

Scott A. Sinex<br />

Department of Physical <strong>Science</strong>s and Engineering<br />

Prince George’s Community College, Largo, Maryland, USA<br />

William E. Singhose<br />

The George W. Woodruff School of Mechanical Engineering<br />

Georgia Institute of Technology, Atlanta, Georgia, USA<br />

Stephen J. Sugden<br />

Faculty of Business<br />

Bond University, Queensland, Australia<br />

Leonie Tickle<br />

Department of Actuarial Studies<br />

Macquarie University, New South Wales, Australia<br />

Elliot Tonkes<br />

Director of Risk and Analytics<br />

Energy Edge Pty Ltd, Brisbane, Australia<br />

Leigh Wood<br />

Faculty of Business and Economics<br />

Macquarie University, New South Wales, Australia


Part I<br />

Engineering


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 3–17 3<br />

Fault Analysis in Power Systems<br />

Mark A. Lau ∗ and Sastry P. Kuruganty<br />

Department of Electrical and Computer Engineering<br />

Universidad del Turabo, Gurabo, Puerto Rico, USA<br />

CHAPTER 1<br />

∗ Address correspondence to: Dr. Mark A. Lau, Department of Electrical and Computer Engineering, Universidad<br />

del Turabo, Road 189 Km 3.3, Gurabo, Puerto Rico 00778-3030, USA; Tel: (+1) 787-743-7979,<br />

Ext. 4174; E-mail: mlau@suagm.edu<br />

Abstract: Fault analysis is an important consideration in power system planning,<br />

protection equipment selection, and overall system reliability assessment. At the<br />

heart of today’s power generation and distribution are high-voltage transmission and<br />

distribution networks. When a fault (e.g., a short circuit) occurs at some point in the<br />

network, the normal operating conditions of the system are upset; if the fault is persistent<br />

severe loss of load, property damage due to fire or explosion, and steep economic<br />

losses can arise as undesirable consequences. Therefore, the correct modeling<br />

of components and the correct fault analysis in power systems are critical to ensuring<br />

safety and reliability. In this <strong>chapter</strong> fault analysis is illustrated via spreadsheets.<br />

Spreadsheets are widely accessible and the ease of programming is the hallmark<br />

feature that renders them appealing to many users. This simple tool is employed to<br />

analyze both symmetrical and unsymmetrical faults in power systems. The determination<br />

of fault currents aids the power engineer in the selection and coordination of<br />

protective equipment to ensure the safe and reliable operation of the system.<br />

Keywords: fault analysis, symmetrical faults, unsymmetrical faults, short circuits, power systems.<br />

1.1 Introduction<br />

The complexity of power systems demands a variety of tools for their correct modeling, analysis,<br />

and design. Classical problems such as power (load) flows, transient stability, dynamic stability,<br />

fault analysis, and economical dispatch are part of the knowledge repertoire of any practicing power<br />

engineer.<br />

This <strong>chapter</strong> discusses fault analysis in power systems utilizing spreadsheets. Fault analysis is<br />

an important aspect in power system planning, protection equipment selection, and overall system<br />

reliability. A fault is defined to be an event or condition that disrupts the normal operation of a power<br />

system. To be more specific, this <strong>chapter</strong> focuses on short circuits in three-phase power systems.<br />

Short circuits may be classified under two categories: symmetrical faults and unsymmetrical faults.<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


4 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Lau and Kuruganty<br />

A three-phase short circuit constitutes a symmetrical fault; single line-to-ground, line-to-line, and<br />

double line-to-ground short circuits are instances of unsymmetrical faults.<br />

In decreasing order of frequency short circuits in three-phase power systems occur as follows:<br />

single line-to-ground, line-to-line, double line-to-ground, and balanced three-phase faults. While<br />

balanced three-phase faults are the least frequent, these faults will be presented first because of their<br />

conceptual simplicity. The material presented in this <strong>chapter</strong> is accessible to most undergraduatelevel<br />

students with some previous exposure to power system concepts. The presentation follows<br />

those of most textbooks [1–4]; equations are given without derivations as they can be found in<br />

standard reference books [1–4]. Instead, the emphasis is placed on the construction of spreadsheet<br />

models to analyze faults in power systems. Applications of spreadsheets in power system analysis<br />

have been reported in the literature [5–8]. It is along this line that this <strong>chapter</strong> is presented,<br />

continuing the efforts initiated by the authors in a power systems course [6, 7].<br />

This <strong>chapter</strong> is organized as follows. Section 1.2 presents a spreadsheet implementation to<br />

analyze balanced three-phase short circuits. Spreadsheet models for analyzing unbalanced threephase<br />

faults are presented in Section 1.3. Subsequently, a discussion on the spreadsheet models and<br />

possible adaptations is given in Section 1.4. Finally, Section 1.6 gives some concluding remarks. It<br />

is pointed out that throughout this <strong>chapter</strong>, spreadsheet models are implemented in Microsoft Excel.<br />

1.2 Symmetrical Faults<br />

A power system is normally treated as a balanced (symmetrical) three-phase network. When a fault<br />

occurs, the symmetry is oftentimes upset, resulting in unbalanced phase currents and phase voltages.<br />

A three-phase symmetrical fault is a special case because it involves all three phases equally at the<br />

fault location. Fault analysis is typically performed by examining the so called sequence networks<br />

of the system being analyzed. In fact, any system can be represented by three sequence networks:<br />

zero-, positive-, and negative-sequence networks. In the special case of a balanced three-phase short<br />

circuit, the resulting fault currents are balanced and, hence, only the positive-sequence network is<br />

considered. For more background information on symmetrical components and sequence networks,<br />

the reader may consult any of the standard books [1–4].<br />

It turns out that fault currents resulting from symmetrical three-phase short circuits can be calculated<br />

from the one-line (or per-phase equivalent) diagram of the system and the pre-fault operating<br />

conditions. During the fault the phase current and phase voltage undergo a subtransient period, followed<br />

by a transient period, before settling down to a steady state. To simplify matters and to make<br />

the analysis amenable to spreadsheet implementation, the following assumptions are made [1–4]:<br />

1. All system voltages are replaced by a single driving voltage at the fault location. This driving<br />

voltage is the pre-fault voltage at the fault location. Further, this pre-fault voltage is assumed<br />

to be the open-circuit voltage at that point.<br />

2. In most applications, load currents are small in comparison to fault currents and may be<br />

neglected.<br />

3. Transformers are represented by their leakage reactances. Winding resistances and shunt<br />

admittances are neglected.


Fault Analysis in Power Systems Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 5<br />

4. Transmission lines are represented by their equivalent series reactances. Series resistances<br />

and shunt admittances are ignored.<br />

5. Synchronous machines are represented by constant-voltage sources behind subtransient reactances.<br />

Armature resistance, pole saliency, and saturation effects are ignored.<br />

To illustrate the analysis of symmetrical faults, consider the five-bus power system whose oneline<br />

diagram is shown in Fig. (1.1). Machine, transformer, and line data are given in Table 1.1. The<br />

data are given in per unit (p.u.) of a common base.<br />

Eg1<br />

Generator 1 Transformer 1<br />

jX" d 1<br />

jXT1 j 0.04 j 0.025<br />

1<br />

jX25<br />

j 0.1<br />

jX45<br />

j 0.05<br />

5 4<br />

2<br />

Transmission lines<br />

j 0.125<br />

jX24<br />

Transformer 2 Generator 2<br />

jXT2 jX" d 2<br />

j 0.02<br />

Fig. (1.1): One-line diagram of power system for symmetrical fault analysis.<br />

Table 1.1: Synchronous machine, transformer, and transmission line data<br />

Generator<br />

Bus Subtransient reactance, X ′′<br />

d (p.u.)<br />

1 0.04<br />

3 0.02<br />

Transformer<br />

Bus-to-Bus Leakage reactance, XT (p.u.)<br />

1–5 0.025<br />

3–4 0.02<br />

Line<br />

Bus-to-Bus Series reactance, XL (p.u.)<br />

2–4 0.125<br />

2–5 0.1<br />

4–5 0.05<br />

It is also assumed that the pre-fault voltage at the faulted bus is VF = 1.05e j0o p.u. Since<br />

machine subtransient reactances are used in the analysis, the currents to be calculated are then<br />

subtransient fault currents. The purpose of the analysis is to determine the subtransient fault currents<br />

and phase voltages in each bus when a three-phase short circuit occurs at bus 1. The calculations<br />

are then repeated for three-phase short circuits occurring at bus 2, 3, and so on.<br />

3<br />

j 0.02<br />

Eg2


18 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 18–40<br />

Use of Spreadsheets for Analyses in Structural Engineering<br />

Nelson Lam<br />

Department of Civil and Environmental Engineering<br />

University of Melbourne, Parkville, Victoria, Australia<br />

CHAPTER 2<br />

Address correspondence to: Dr. Nelson Lam, Department of Civil and Environmental Engineering, School<br />

of Engineering, University of Melbourne, Parkville 3010, Australia; Tel: (+61) 3-8344-7554; E-mail:<br />

ntkl@unimelb.edu.au<br />

Abstract: Structural engineering is a branch of engineering that is concerned with<br />

the analysis and design of elements such as beams, frames, trusses, and other mechanical<br />

structures whose principal function is to provide the necessary supporting<br />

feature to withstand the mechanical loads, or related operating conditions, normally<br />

associated with structures such as buildings, bridges, cranes, airplanes, and so on.<br />

This <strong>chapter</strong> concentrates on the analysis of beams, wall frames, and buildings.<br />

More specifically, the analyses of these structures are illustrated via Microsoft Excel<br />

spreadsheets. Spreadsheets may be used to develop quite sophisticated applications<br />

that can automate the intensive calculations commonly encountered in structural<br />

analysis.<br />

Keywords: structural analysis, beams, walls, frames, modal analysis.<br />

2.1 Introduction<br />

Excel spreadsheets are widely used in design offices for providing assistances to the design of<br />

engineered structures. This type of spreadsheet program is typically used for accessing a database<br />

of design parameters (for the selection of products, for example) or to expedite the checking of the<br />

design against a list of criteria for ensuring code compliances. Essentially, Excel spreadsheets have<br />

been used as database managers to replace the tedious tasks of looking up design charts and tables<br />

manually, and for checking compliances.<br />

This <strong>chapter</strong> is also concerned with the application of Excel in structural engineering design and<br />

analysis, with an emphasis on the potential usage of the platform for educational purposes and for<br />

the more intensive analytical tasks that are traditionally performed by proprietary structural analysis<br />

packages. Such potential uses of Excel that are being explored in this <strong>chapter</strong> have not been widely<br />

recognized.<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Use of Spreadsheets for Analyses Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 19<br />

The use of Excel in educating engineers with elementary structural mechanics is first illustrated.<br />

The conventional approach to the solution of problems in engineering statics (i.e., calculation of<br />

shear forces and bending moments) would always require solving simultaneous equations for determining<br />

the values of the support reactions. It is demonstrated herein that with the use of Excel<br />

the solution could be obtained very differently by an intuitive approach. For example, the value of<br />

a vertical support reaction of a simply supported beam can be determined by trial-and-error until<br />

equilibrium is satisfied (i.e., end-moments at free ends approaching zero values). Embodied in this<br />

trial-and-error process is the educational objective of having the student visualize the conditions<br />

of equilibrium through graphical display of the forces and moments surrounding the beam while<br />

different reaction values are being keyed in. Essentially, the focus of attention is on the physical<br />

conditions of the beam as displayed graphically, which is in contrast to the conventional treatment<br />

of the problem by linear algebra. This alternative approach to engineering statics is particularly<br />

useful to students who are introduced to the concepts for the first time. The teaching of the conventional<br />

solution method could be introduced subsequently when the underlying concepts have been<br />

well understood.<br />

The conventional method of finding deflections of a beam would require finding the values<br />

of constants in polynomial expressions based on pre-defined boundary conditions. When Excel<br />

is employed, the solution can be obtained intuitively in two steps: (i) deforming the beam with a<br />

constant or variable curvature along its length and (ii) rotating the beam (as a rigid body) in the<br />

vertical plane about a support until the beam is leveled with all the supports. The trial-and-error<br />

procedure of deforming and rotating the beam about one of its supports serves to engage the students<br />

into finding the deflection profile by intuition while alleviating the need to become heavily involved<br />

with algebra. The educational attribute can be further enhanced by the use of interactive graphics<br />

display in Excel. A similar intuitive approach could be employed for determining the value of the<br />

reaction at a redundant (say interior) support through visualizing the beam gradually leveling with<br />

the support point as the reaction value is gradually varied. A full description of the programming is<br />

presented in Section 2.2.<br />

Section 2.3 explores the use of standard matrix operations (involving addition, multiplication,<br />

and inversion of matrices and vectors) for analyzing lateral resisting elements including building<br />

frames, structural walls, or wall-frame elements. The flexibility matrix of a lateral resisting element<br />

can be constructed readily once the deflection of the element at every floor level in the building<br />

has been identified. The flexibility matrix can be inverted in Excel to give the stiffness matrix.<br />

Importantly, stiffness matrices representing contributions by individual lateral resisting elements<br />

can be summed to represent joint actions that are facilitated by diaphragm actions of the building<br />

floors.<br />

Section 2.4 illustrates the use of Excel for undertaking the more advanced (dynamic) analysis<br />

of single-story and multi-story buildings. The simulation of the response displacement time-history<br />

of a single-degree-of-freedom (SDOF) system can be accomplished by what is known as the central<br />

difference method of step-by-step time integration as is illustrated in Section 2.4.1. The forward<br />

marching algorithm featured in this solution method can be implemented easily by a column array<br />

in Excel. Such a column array can be constructed from top to bottom using the fill down command.<br />

Interestingly, the use of a column array for finding the solution for a SDOF system can be expanded<br />

into a rectangular array for solving multiple systems, the results of which can be used for plotting<br />

the response spectra of the applied excitations. The rectangular array can be constructed from


20 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Nelson Lam<br />

left to right using the fill right command. The solution of eigenvalues (modal natural periods)<br />

and eigenvectors (mode shapes) in a dynamic modal analysis could also be calculated by Excel<br />

as illustrated in Section 2.4.2. The spreadsheet solution features iterations through populating the<br />

worksheet with column arrays from left to right (using the fill right command). Every iteration<br />

commences at the column array on the left and then ends at the column array on the right. In<br />

perspective, the forward marching algorithm, the calculation and plotting of the response spectra<br />

and the solution of the modal periods and mode shape vectors have all been accomplished by fully<br />

exploiting the standard row and column operations in Excel. Further details of programming in<br />

Excel for structural dynamic analysis is given in Section 2.4. Much fuller details of algorithm<br />

development for structural dynamic analysis and simulations are presented in [1, 2]. The use of<br />

Excel for analysis of cracked reinforced concrete cross-sections based on the fiber-element approach<br />

is presented in [3]. Results obtained from the latter program for analysis of cracked reinforced<br />

concrete can be compared with recommendations in [4, 5].<br />

Another important attribute of Excel suitable for engineering education and training is its transparency.<br />

Conventional programming languages such as Fortran, C++, or Visual Basic present the<br />

program algorithm in the usual text format, effectively delivering information in one dimension.<br />

Elaborate algorithms of large computer programs are therefore difficult to follow. In contrast, an<br />

algorithm in Excel is the worksheet itself, thereby delivering information in two dimensions. Algorithms<br />

in Excel can be introduced by a sequence of worksheets, each of which presents a snapshot<br />

of the progressive development of a spreadsheet program (from a blank sheet into its final form).<br />

The presentation of a worksheet for illustration to the user can be enhanced in a number of ways<br />

including the use of annotations, the coloring of cells (to identify which are the ones for the input<br />

of data). Thus, a program in Excel can be introduced to users without the need of a user’s<br />

manual. Details of every step in the computations are evident in the spreadsheet itself if only row<br />

and column operations have been used. This enables users to make modifications to the program<br />

customizing specific needs, while having full knowledge of its operations as well as the underlying<br />

computations. The blackbox syndrome of a computer program is hence eliminated.<br />

2.2 Beam Analysis (Elementary Level)<br />

The teaching of elementary structural mechanics using Excel may begin with the cantilever beam<br />

for illustration purposes. For any location on the beam which is measured at distance x from its<br />

free-end, values of 〈x−xi〉 = max(x−xi, 0) are calculated where subscript i denotes the position<br />

of the applied point force and xi is the distance of the point force Fi measured from the free-end.<br />

Observe that when x−xi is a positive value, 〈x−xi〉 is taken to be equal to x−xi, or else 〈x−xi〉<br />

is taken to be equal to zero. This formulation allows the calculation of shear force and bending<br />

moment values to be generalized into simple one-line expressions as shown by Equations (2.1a)<br />

and (2.1b) – based on the usual free-body diagram principles and the resolving of forces and taking<br />

moments about the point of interest.<br />

SF(x)=<br />

BM(x)=<br />

N<br />

∑<br />

i=1<br />

N<br />

∑<br />

i=1<br />

Fi〈x−xi〉 0<br />

Fi〈x−xi〉 1<br />

(2.1a)<br />

(2.1b)


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 41–63 41<br />

Optimal Control of Dynamical Systems<br />

Mark A. Lau 1,∗ and William E. Singhose 2<br />

1 Department of Electrical and Computer Engineering<br />

Universidad del Turabo, Gurabo, Puerto Rico, USA<br />

2 The George W. Woodruff School of Mechanical Engineering<br />

Georgia Institute of Technology, Atlanta, Georgia, USA<br />

CHAPTER 3<br />

∗ Address correspondence to: Dr. Mark A. Lau, Department of Electrical and Computer Engineering, Universidad<br />

del Turabo, Road 189 Km 3.3, Gurabo, Puerto Rico 00778-3030, USA; Tel: (+1) 787-743-7979,<br />

Ext. 4174; E-mail: mlau@suagm.edu<br />

Abstract: Optimal control techniques have numerous applications in engineering,<br />

economics, finance, biology, medicine, and many other fields. In spite of the utility<br />

of these techniques, the presentation of the topic of optimal control is normally<br />

reserved for graduate studies within specialties (e.g., systems engineering). In this<br />

<strong>chapter</strong> we present some illustrative examples in optimal control whose numerical<br />

solutions are obtained using the built-in solver capabilities of spreadsheets. Our<br />

hope is that the important and interesting topic of optimal control can be introduced<br />

to undergraduate students in a less intimidating manner when spreadsheets are used.<br />

Keywords: optimal control, Pontryagin’s minimum principle, dynamical systems.<br />

3.1 Introduction<br />

Optimal control theory provides the means to drive a machine as fast as possible. Or, it can provide<br />

a controller that moves a machine in the most efficient possible way. Optimal control can even<br />

provide the best method for balancing the needs for fast and efficient motion. It is the branch of<br />

mathematics that furnishes the conditions or techniques for deriving functions (control laws) so as<br />

to optimize a given criterion (cost functional). The foundations of the theory were established in<br />

the 1960s thanks to the work of Lev Pontryagin, his collaborators, and Richard Bellman. A typical<br />

control problem includes:<br />

1. A cost functional that is a function of state and control variables.<br />

2. A set of differential equations that models the interactions between control variables and state<br />

variables.<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


42 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Lau and Singhose<br />

3. In some optimal control problems, ancillary constraints may be included. For example, fixed<br />

end states, energy usage, control saturation, and so on.<br />

The solid mathematical foundations that underpin the theory of optimal control have provided<br />

the impetus for finding applications in engineering, economics, finance, biology, medicine, among<br />

other fields. Only a brief outline of the mathematical background will be provided in this <strong>chapter</strong>;<br />

for a more detailed study of the subject the reader is referred to some of the classic books in optimal<br />

control [1–3]. In spite of the elegance of its theory and the richness of applications, most undergraduate<br />

engineering students receive very limited or no exposure to optimal control. In fact, our<br />

experience as instructors reveals that the presentation of this topic is normally reserved for graduate<br />

studies within specialties (e.g., systems engineering) that make use of the theory of optimal control.<br />

We believe that optimal control theory is filled with profound ideas and that undergraduate engineering<br />

students will benefit from the study of this topic. It is our intention in this <strong>chapter</strong> to<br />

offer an accessible introduction to optimal control with the aid of spreadsheets. In particular, the<br />

Microsoft Excel Solver tool will be employed to solve optimal control problems. The spreadsheet<br />

approach has been used in the teaching of undergraduate economics and business courses [4–6].<br />

In [4], detailed examples of continuous-time systems with first order dynamics are solved using<br />

the Solver tool; likewise, [5] uses the same tool to explain the optimization problem in a first<br />

order, discrete-time system, while [6] presents spreadsheet implementations for solving dynamic<br />

optimization problems. In this <strong>chapter</strong> we present some illustrative examples dealing with second<br />

order, continuous-time systems that might appeal to undergraduate engineering students.<br />

The reason for using spreadsheets is that most students are familiar with such tools. Additionally,<br />

spreadsheets are widely available and very straightforward to set up, thus making the programming<br />

requirement fairly straightforward. The rest of the <strong>chapter</strong> is organized as follows. Section 3.2<br />

briefly presents the mathematical background for solving optimal control problems. Subsequently,<br />

Section 3.3 discusses a number of optimal control examples and solutions using spreadsheets. In<br />

Section 3.4, we offer our perspective on classroom use, and finally, some concluding remarks are<br />

given in Section 3.5.<br />

3.2 Mathematical Background<br />

3.2.1 Pontryagin’s Minimum Principle<br />

The most important component of optimal control is the minimization of a cost function, such as<br />

move time or fuel usage. Here we provide a statement of necessary conditions for the minimization<br />

of a cost functional. More details can be found in [1–3].<br />

Consider a dynamical system modeled by the ordinary differential equation (with ˙ (·) denoting<br />

the derivative with respect to time)<br />

˙x(t)=f t,x(t),u(t) <br />

(3.1)<br />

together with<br />

x(t0)=x0, u(t)∈U , t ∈[t0, t f] (3.2)<br />

where f : [t0,t f]×R n × U ↦→ R n is a continuously differentiable function, x(t) ∈ R n is the state<br />

vector, and u(t) is an input vector from the set of admissible controls U ⊂ R m . The system is


Optimal Control of Dynamical Systems Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 43<br />

observed from some initial time t0 to a final time t f . The control u(t) must be chosen so as to<br />

minimize the cost functional<br />

J = h t f,x(t f) t f<br />

+ g<br />

t0<br />

t,x(t),u(t) dt (3.3)<br />

where h : [t0, t f]×R n ↦→R and g : [t0, t f]×R n ×U ↦→R are assumed to be continuously differentiable.<br />

In order to solve the optimal control problem, Pontryagin created a function that combined the<br />

system dynamics and the cost function. He called it the Hamiltonian, H , and defined it to be<br />

H t,x(t),p(t),u(t) = g t,x(t),u(t) + p T (t)f t,x(t),u(t) <br />

where p(t)∈R n is the costate vector and (·) T denotes vector or matrix transposition. The costate<br />

vector is obtained from the partial derivatives of the Hamiltonian, with respect to the state variables,<br />

namely,<br />

˙p ∗ (t)=−H T<br />

∗ ∗ ∗<br />

x t,x (t),p (t),u (t)<br />

where(·) ∗ denotes optimal quantities.<br />

Pontryagin’s minimum principle states that the optimal state trajectory x ∗ (t) resulting from<br />

application of the optimal control u ∗ (t) must minimize the Hamiltonian. That is,<br />

(3.4)<br />

(3.5)<br />

u ∗ (t)= arg min<br />

u(t)∈U H t,x ∗ (t),p ∗ (t),u(t) , ∀t ∈[t0, t f], ∀u(t)∈U (3.6)<br />

If the final state x(t f) is not fixed, then we have the following transversality condition<br />

p ∗ (t f)=h T x t f,x ∗ (t f) <br />

where hx is the gradient of h. Equations (3.5)–(3.7) give the necessary conditions for optimal<br />

control. If x(t f) is fixed, then Equation (3.7) is not needed; in this case p ∗ (t f) = c, for some<br />

constant vector c.<br />

3.2.2 The Runge-Kutta Method for Solving Differential Equations<br />

As stated in the previous section, solving optimal control problems involves solving a system of<br />

ordinary differential equations. For computer implementation we need a numerical technique to<br />

obtain solutions. There are many numerical techniques available, but perhaps one of the most<br />

popular is the Runge-Kutta method [7]. Here we present the Runge-Kutta method in the context of<br />

the system of differential equations<br />

<br />

˙x1(t) = f1 t,x1(t),x2(t), p1(t), p2(t) <br />

<br />

˙x2(t) = f2 t,x1(t),x2(t), p1(t), p2(t) <br />

<br />

˙p1(t) = f3 t,x1(t),x2(t), p1(t), p2(t) <br />

<br />

˙p2(t) = f4 t,x1(t),x2(t), p1(t), p2(t) <br />

(3.8)<br />

with given (or assumed) initial conditions x1(0), x2(0), p1(0), and p2(0).<br />

(3.7)


64 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 64–83<br />

Spreadsheet Conditional Formatting Illuminates<br />

Investigations into Modular Arithmetic<br />

David Miller 1 and Stephen Sugden 2,∗<br />

1 Department of Mathematics<br />

West Virginia University, Morgantown, West Virginia, USA<br />

2 Faculty of Business<br />

Bond University, Queensland, Australia<br />

CHAPTER 4<br />

∗ Address correspondence to: Dr. Stephen Sugden, Faculty of Business, Bond University, QLD 4229, Aus-<br />

tralia; Tel: (+61) 7-5595-3325; E-mail: ssugden@bond.edu.au<br />

Abstract: Modular arithmetic has often been regarded as something of a mathematical<br />

curiosity, at least by those unfamiliar with its importance to both abstract algebra<br />

and number theory, and with its numerous applications. However, with the ubiquity<br />

of fast digital computers, and the need for reliable digital security systems such as<br />

RSA, this important branch of mathematics is now considered essential knowledge<br />

for many professionals. Indeed, computer arithmetic itself is, ipso facto, modular.<br />

This <strong>chapter</strong> describes how the modern graphical spreadsheet may be used to clearly<br />

illustrate the basics of modular arithmetic, and to solve certain classes of problems.<br />

Students may then gain structural insight and the foundations laid for applications to<br />

such areas as hashing, random number generation, and public-key cryptography.<br />

Keywords: modular arithmetic, conditional formatting.<br />

4.1 Introduction<br />

Sometimes described as “clock-arithmetic,” at least at high-school level, modular arithmetic was<br />

sometimes presented there as bit of a curiosity, with little practical application. Perhaps with the<br />

advent and dominance of digital timepieces, the “clock-arithmetic” terminology has faded, however<br />

this field of mathematical study is now more important than ever. Pioneered by Euler, and greatly<br />

advanced by Gauss in his Disquisitiones Arithmeticae in 1801 [1], modular arithmetic was indeed<br />

regarded as a curiosity at that time. Given that integer arithmetic on a digital computer is inherently<br />

modular (see Section 4.2), and that computers permeate our daily lives, it seems somewhat strange<br />

that our pre-tertiary students learn essentially nothing of the very important topic of modular arithmetic.<br />

More than this, a working knowledge of modular arithmetic is essential for the mathematical<br />

study of modern cryptographic systems such as RSA. We believe that the time for this material to<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Spreadsheet Conditional Formatting Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 65<br />

be included in the school curriculum is long overdue. With just a little effort, this material may be<br />

made accessible and, hopefully, appealing to secondary school mathematics students.<br />

In this <strong>chapter</strong> we show that informative investigations may be carried out using spreadsheets[2]<br />

and present new spreadsheet-based approaches for computing and illustrating multiplication tables<br />

for modular arithmetic. The modular arithmetic spreadsheet described in this <strong>chapter</strong> allows investigation<br />

of a variety of properties and concepts in modular arithmetic, including that of modular<br />

inverse, which is essential for understanding of public-key cryptosystems such as RSA.<br />

4.2 Modular Arithmetic<br />

Due in significant part to its widespread application to cryptography and coding theory, basic knowledge<br />

of this important branch of mathematics is now considered almost essential for IT professionals,<br />

and others. However, in the experience of the authors, relatively few IT graduates seem to<br />

appreciate that integer arithmetic on a digital computer is none other than modular arithmetic. This<br />

is so, as all integer operations are performed modulo some power of 2 – it is the nature of a digital,<br />

binary CPU. All integer arithmetic done on a digital computer is with respect to a maximum word<br />

size, and therefore is modulo some positive integer. For example, on a contemporary desktop machine,<br />

an integer may be represented by 32 bits. This means that additions and multiplications will<br />

be modulo 2 32 (for cardinals), or 2 31 (for signed integers). When two integers are added on such<br />

a machine, and the sum exceeds the maximum value representable with 32 bits, e.g., 2 32 − 1 for a<br />

cardinal, then the processor overflow flag will be set, and the sum will only be correct modulo 2 32 .<br />

In many instances, this situation corresponds to a serious run-time error. However, if we are doing<br />

arithmetic modulo 2 32 , then we may legitimately ignore the overflow flag, as this is just the result<br />

we want.<br />

4.2.1 Rules of the Game<br />

What is modular arithmetic and how does it work? What are the basic rules? For the most part,<br />

these are very simple. The first concept we need is that of remainder or residue. Suppose we wish to<br />

divide 38 by 9. We have 38=(4×9)+2. In this equation, 38 is the dividend, 9 is the divisor, 4 is the<br />

quotient, and 2 called the remainder or residue. The word residue means “something left over”. By<br />

definition, it is non-negative and less than the divisor, so it could be zero. In other words, residues<br />

run from 0 up to one less than the divisor. In some contexts the divisor is called the modulus (plural<br />

moduli), and we consider this very soon. Given any dividend and a non-zero divisor, the quotient<br />

and remainder are unique. This is guaranteed by the so-called division algorithm.<br />

Theorem 4.1 (The division algorithm) Given integers n and d = 0, there exist unique integers q<br />

(quotient) and r (residue or remainder) such that n=qd+ r and 0≤r≤d− 1.<br />

Definition 4.1 In Theorem 4.1, the residue r is also written as n mod d.<br />

Example 4.1 We have 38=(4×9)+2, so 38 mod 9=2.<br />

Example 4.2 We have−38=(−5×9)+7, so−38 mod 9=7.


66 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Miller and Sugden<br />

Remark 4.1 When computing a mod b for specific integers a and b, we may think of adding or<br />

subtracting as many copies of b from a as required until we finally arrive at a number in the correct<br />

range, i.e., between 0 and b−1 inclusive. For example, to compute 89 mod 12, keep removing<br />

(subtracting) twelves until you are left with 5. This can be regarded as removing seven copies of 12,<br />

or equivalently, dividing 89 by 12 to obtain a quotient of 7 (irrelevant for modular arithmetic) and<br />

remainder 5 (the important part). Thus, 89 mod 12=5. To compute(−46) mod 12, do pretty much<br />

the same thing, except that we need to keep adding twelves until we are “in range,” i.e., between<br />

0 and 11 inclusive. Adding four twelves to (−46) gives us 2, which is the answer. Thus, (−46)<br />

mod 12=2.<br />

Exercise 4.1 Verify that the conditions of Theorem 4.1 are satisfied for each of the examples just<br />

considered.<br />

4.2.2 Congruence with Respect to a Modulus<br />

If two integers x and y have the same residue with respect to a given modulus m, i.e., x mod m =<br />

y mod m, then we say that they are congruent with respect to this modulus and write x≡y(mod m).<br />

For example, 22 and 40 are congruent with respect to the modulus 6, since they both have remainder<br />

4 after division by 6. We write 22≡40(mod 6). Another way to think of this is that the numbers<br />

x and y differ by a multiple of m, i.e., x−y≡0(mod m). Thus, 22≡40(mod 6) as 22 and 40 differ<br />

by 18, which is a multiple of 6.<br />

It is important to realize that the congruence x ≡ a(mod m) defines an infinite arithmetic sequence<br />

of integers. For example, the congruence x≡1(mod 2) defines the sequence of odd numbers:<br />

... − 7,−5,−3,−1,1,3,5,7, ... This sequence may be written as xn = 1+2n; n∈Z. Notice<br />

that we transform the congruence x≡1(mod 2) into an equation by introducing a parameter n.<br />

4.2.3 Arithmetic Operations<br />

We have seen that a modulus is simply a positive integer to be thought of as a divisor. If we think of<br />

it this way, then we can imagine that it generates a quotient and a remainder. For modular arithmetic,<br />

we are interested only in the remainder (residue). Without loss of generality, we deal with positive<br />

divisors in this <strong>chapter</strong>. Clearly, zero cannot be a divisor, and we are not interested in m=1 either,<br />

since remainders are always zero when we divide by 1; thus, m≥2.<br />

Now suppose a,b,c,d are any integers. We wish to add, subtract, multiply and divide these<br />

numbers with respect to a particular modulus m≥2. What are the rules? It turns out that, for the<br />

most part, they are about as simple as we could hope for. For example, suppose a ≡ 2(mod 7)<br />

and b≡6(mod 7). Then a+b≡(2+6)(mod 7), a−b≡(2−6)(mod 7), a×b≡(2×6)(mod 7).<br />

More generally,<br />

If a ≡ c (mod m) and b≡d (mod m) then, for n≥0,we have<br />

a+b ≡ (c+d)(mod m)<br />

a−b ≡ (c−d)(mod m)<br />

ab ≡ cd(mod m)<br />

a n ≡ c n (mod m)


84 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 84–106<br />

Computational Problem Solving in Context:<br />

From Arithmetic Sequences to Polygonal-like Numbers<br />

Sergei Abramovich<br />

Department of Curriculum and Instruction<br />

State University of New York at Potsdam, Potsdam, New York, USA<br />

CHAPTER 5<br />

Address correspondence to: Prof. Sergei Abramovich, Department of Curriculum and Instruction, State<br />

University of New York, 210 Satterlee Hall, Potsdam, New York 13676, USA; Tel: (+1) 315-267-2541;<br />

E-mail: abramovs@potsdam.edu<br />

Abstract: The learning of mathematical concepts can be aided by the use of technology<br />

and graphical visualization. The use of modern tools can greatly enhance the<br />

learning experience by encouraging inquiry and deepening one’s understanding. In<br />

this <strong>chapter</strong> triangular, square, and polygonal-like numbers are explored in context<br />

using spreadsheets. The context provides the element of relevance that learners need<br />

in order to appreciate concepts that might otherwise seem abstract in nature.<br />

Keywords: contextual problem solving, arithmetic sequences, polygon-like numbers.<br />

5.1 Introduction<br />

A number sequence in which the difference between any two consecutive terms is a constant is<br />

called an arithmetic sequence. The simplest example of such a sequence is the sequence of counting<br />

numbers 1, 2, 3, 4, ..., where the difference between any two consecutive terms is one. Similarly,<br />

one can consider the sequence of consecutive odd (1, 3, 5, 7, ...) or even (2, 4, 6, 8, ...) numbers<br />

as arithmetic sequences with the difference two.<br />

Many problems in mathematics lead to the summation of consecutive counting, odd, or even<br />

numbers. Finding such sums can be extended to the summation of other arithmetic sequences.<br />

Partial sums of arithmetic sequences (e.g., 1, 1+2=3, 1+2+3=6, 1+2+3+4=10, and so<br />

on) form new number sequences known as polygonal numbers [1]. In particular, these numbers,<br />

having strong connection to geometry, include triangular (1, 3, 6, 10, ...) and square (1, 4, 9, 16,<br />

...) numbers which can already be found in the elementary school curriculum as links between<br />

different mathematical concepts (e.g., [2]).<br />

An arithmetic sequence is one of the most basic concepts of algebra and number theory. The<br />

study of arithmetic sequences and their partial sums lends itself to the joint use of context and<br />

technology. In particular, the use of a spreadsheet in teaching algebra and number theory topics<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Computational Problem Solving in Context Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 85<br />

to students at pre-college level and their future teachers of mathematics has been well documented<br />

in the literature [3–10]. The current approach to teaching mathematics in context confronts mathematics<br />

educators with the task of representing traditional number theory concepts in informal way,<br />

something that gradually develops a path to mathematical ideas through their numerical representation<br />

in computational environments. Such an approach is suggested below in the form of number<br />

of “authentic” situations supported by the use of a spreadsheet.<br />

5.2 Polygonal Numbers and Second Order Difference Equations<br />

It should be noted that polygonal numbers have a more complicated nature than arithmetic sequences.<br />

This complexity deals with the fact that whereas the difference between two consecutive<br />

terms of an arithmetic sequence is a constant, the difference between two consecutive polygonal<br />

numbers varies as a linear function of their positional rank. Put another way, whereas the first differences<br />

between two consecutive polygonal numbers form an arithmetic sequence, their second<br />

differences have constant values. For example, the sequence tn defined recursively<br />

Δ2tn = tn+2− 2tn+1+tn = 1, t1 = 1, t2 = 3 (5.1)<br />

represents polygonal numbers of side three, or, alternatively, triangular numbers. The quantity Δ2tn<br />

in Equation (5.1) is the second difference of the sequence tn.<br />

Likewise, the sequence sn defined recursively<br />

Δ2sn = sn+2− 2sn+1+ sn = 2, s1 = 1, s2 = 4 (5.2)<br />

represents polygonal numbers of side four, known also as square numbers.<br />

In the last two decades, triangular and square numbers as concepts appropriate for K-12 curriculum<br />

appeared in a number of mathematics education publications in the United States and elsewhere<br />

[1, 7, 11–15], including standards for teaching mathematics [2, 16]. This prompts the idea<br />

of embedding these concepts in a grade-appropriate context enhanced by a spreadsheet as a means<br />

of motivating mathematical learning. Such a unity of context, mathematics, and technology makes<br />

it possible to introduce triangular and square numbers as problem-solving tools.<br />

More generally, the sequence pn defined recursively through its second difference<br />

Δ2pn = pn+2− 2pn+1+ pn = m−2, p1 = 1, p2 = m (5.3)<br />

represents polygonal numbers of side m, or, alternatively, m-gonal numbers. Equations (5.1)–(5.3)<br />

are linear non-homogeneous difference equations of the second order. The description of polygonal<br />

numbers through a linear difference equation of the second order resembles the definition of<br />

Fibonacci numbers, the properties of which, however, are quite different from those of polygonal<br />

numbers. This is due to the fact that Fibonacci numbers are defined by a homogeneous difference<br />

equation and polygonal numbers are defined through non-homogeneous difference equations.<br />

One can solve Equation (5.1) as a non-homogeneous difference equation by finding the sum of<br />

the general solution to the homogeneous equation tn+2− 2tn+1+ tn = 0 in the form t h n = C1+C2n<br />

and a partial solution t p n = n(n+1)/2. Then tn = t h n +t p n = C1+C2n+n(n+1)/2. Using the initial


86 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Sergei Abramovich<br />

conditions introduced in Equation (5.1) it follows that when n=1 one has t1 = 1= C1+C2+ 1 or<br />

C1 =−C2; when n=2 one has t2 = 3= C1− 2C1+ 3 whence C1 = 0 and C2 = 0. Thus,<br />

tn = n(n+1)<br />

, n=1, 2, 3,... (5.4)<br />

2<br />

Similarly, Equations (5.2) and (5.3) can be shown to have the solutions<br />

and<br />

respectively.<br />

5.3 Triangular Numbers<br />

sn = n 2 , n=1, 2, 3,... (5.5)<br />

pn = (m−2)n2 +(4−m)n<br />

, n=1, 2, 3,... (5.6)<br />

2<br />

5.3.1 Establishing Context for Triangular Numbers<br />

In what follows, the use of a spreadsheet will be considered, using Pollak’s [17] terminology, in<br />

a “whimsical” context. While it may be argued that problems of whimsy have only superficial<br />

connection to the real world [18], the recent use of the term modeling embraces all possible relations<br />

between mathematics and the world outside it [19]. It appears that one’s perception of what is<br />

whimsical and what is not largely depends on one’s experience; in fact, many of today’s real-life<br />

situations seemed like fictions yesterday. Furthermore, the strong relationship that exists between<br />

modeling and problem solving suggests the importance for the spreadsheet modeling to be carried<br />

out in a whimsical context that very often provides a powerful cognitive milieu for solving problems.<br />

For example, Engel [20] explored such “whimsical” contexts as fishing, book reading, and coin<br />

tossing. It has been shown that each of these contexts is conducive for using modeling strategies as<br />

means of instruction and developing the habit of seeing possible applications of mathematics. Note<br />

that context itself does not account for the mathematical content – the latter usually begins with<br />

a quantitative inquiry into the former, something that may be referred to as mathematization. We<br />

begin with<br />

Problematic Situation (PS) 5.1 Once upon a time, Hilton built a hotel in Atlantic City shaped as<br />

a long parallelepiped with more than 100 rooms on each storey overlooking the waterline of the<br />

ocean. The 13th storey turned out to be a dangerous place to stay: Every night a ghost visited a<br />

room there. It was observed (see Fig. (5.1)) that the ghost started with room 1, on the second night<br />

he emerged in room 3, on the third night he emerged in room 6, then he emerged in room 10, and so<br />

on.<br />

After a few such nights the hotel’s manager hired a student from a local college to investigate<br />

the behavioral pattern of the ghost by using a spreadsheet. More specifically, the manager wanted<br />

to know:


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 107–115 107<br />

Enzyme Kinetics for Novice Learners:<br />

Numerical Simulation in Excel<br />

Scott A. Sinex ∗ and Barbara A. Gage<br />

Department of Physical <strong>Science</strong>s and Engineering<br />

Prince George’s Community College, Largo, Maryland, USA<br />

CHAPTER 6<br />

∗ Address correspondence to: Prof. Scott A. Sinex, Department of Physical <strong>Science</strong>s and Engineering,<br />

Prince George’s Community College, Largo, Maryland 20774-2199, USA; Tel: (+1) 301-341-3023; E-mail:<br />

ssinex@pgcc.edu<br />

Abstract: Through an interactive Excel spreadsheet and accompanying activity,<br />

first-year college students explore enzyme kinetics, experimental error, and the behavior<br />

of inhibitors. Many “what if” questions drive students to discover how a<br />

variety of parameters influence results.<br />

Keywords: enzyme kinetics, inhibitors, non-linear regression.<br />

6.1 Introduction<br />

Enzyme kinetics [1, 2] finds its way into every college biology textbook and usually is mentioned in<br />

the chemical kinetics <strong>chapter</strong> of general chemistry textbooks. Because so many biochemical reactions<br />

[2] are mediated by enzymes, it is important to understand their kinetics. Biology students [3]<br />

may encounter enzyme kinetics before seeing chemical kinetics in the second semester of general<br />

chemistry. Enzyme kinetics is a natural extension of chemical kinetics concepts, although, it can appear<br />

to use a completely different language. Since enzyme kinetics is an important biological topic<br />

in molecular biology and microbiology, can general chemistry instructors get it into the curriculum?<br />

This <strong>chapter</strong> introduces an interactive Microsoft Excel spreadsheet (or Excelet) and accompanying<br />

guided-inquiry activity to expose students to the kinetics of enzyme reactions, including<br />

analyzing data, dealing with experimental error, and observing the effects of inhibitors. Data analysis<br />

by both linear and non-linear regression analyses is covered as well as analysis of experimental<br />

results. The use of Excelets as discovery learning tools has been recently described in [4, 5].<br />

To use this Excelet, students need Microsoft Excel with the Analysis ToolPak and Solver Add-in<br />

loaded (instructions are included in the Excelet on the needed Add-ins tab). Students will navigate<br />

using the tabs at the bottom of the screen (see Fig. (6.1)). Students should have an introduction to<br />

using the interactive features of Excelets and how to explore a variable beforehand. Data analysis is<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


108 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Sinex and Gage<br />

Fig. (6.1): Tabs on Excelet.<br />

handled by the “just add data” aspect of the Excelet, where all graphs and calculations are already<br />

set up. Students need to know the basics of mathematical modeling (e.g., regression, goodness-offit,<br />

and so on) as described in [6].<br />

6.2 The Kinetics of Enzyme Reactions Excelet<br />

To get the most out of this discussion, the reader needs to open the interactive Excel spreadsheet<br />

and accompanying activity. First we review some basic information from chemical kinetics and<br />

link to other Excelets that review the basic concepts even further. Understanding this information<br />

is required if students are going to grasp enzyme kinetics.<br />

We are investigating the classic reaction with the rate constants as given by<br />

S+E<br />

k1<br />

−−−−⇀ ↽−−−−<br />

k2<br />

ES<br />

kcat<br />

−−−−−→ E+ P (6.1)<br />

where S is the substrate, E is the enzyme, ES is the enzyme-substrate complex, and P is the product.<br />

The calculations are similar to concepts outlined in [7] and can demonstrate the validity of the steady<br />

state approximation. The similarity of enzyme kinetics to homogeneous catalysis is shown in [8],<br />

wherein some elucidating points on the mechanisms occurring in enzyme kinetics are illustrated.<br />

This Excelet uses manipulatable variables that feed into the Michaelis-Menten equation to calculate<br />

the initial velocity of the reaction, v0, on the kinetics plot tab according to<br />

where<br />

v0 = vmax(S)<br />

KM+(S)<br />

vmax = kcat(E)0 and KM = k2+ kcat<br />

The kinetics plot tab illustrates a variety of enzymes with substrates. We are trying to get<br />

students to see how these substrate/enzyme variables influence the graph. How vmax and KM are<br />

determined from the graph is also illustrated.<br />

Students then explore the behavior of the concentrations of the substrate, enzyme, enzymesubstrate<br />

complex, and the product over time on the S, E, & P over time tab by changing the various<br />

rate constants (k1, k2, and kcat) and initial concentrations of substrate, (S)0, and enzyme, (E)0.<br />

This part of the Excelet is a system’s dynamic model that uses difference equations to calculate<br />

concentrations over time. The actual mathematical equations (differential equations converted to<br />

k1<br />

(6.2)<br />

(6.3)


Enzyme Kinetics for Novice Learners Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 109<br />

difference equations or see [7]) are given on this tab of the Excelet if you scroll down below the<br />

graph, a sample of which is shown in Fig. (6.2).<br />

Fig. (6.2): Concentration over time plot.<br />

A similar plot is employed on the Initial Rate S tab that shows how the initial rate, which is a<br />

common measurement in enzyme experiments, is determined from the graph.<br />

6.3 Transformed Data<br />

If the enzyme kinetics data follows the form of the Michaelis-Menten equation then mathematically<br />

it is a rectangular hyperbola and can be fit by non-linear regression techniques or the data can be<br />

transformed to a linear plot and fit using linear regression. We look at the common transformations<br />

(Table 6.1) used by biochemists [9] to fit the data to find the various parameters: vmax, KM, and kcat<br />

(see transformed data tab). Historically, the data were transformed to produce linear plots, which in<br />

the pre-technology age was the only way to analyze the data (using rulers and graph paper). Analysis<br />

improved with the addition of linear regression, especially employing computational technology.<br />

A big advantage of linear plots is the ability to spot behavior that is non-linear. Many errors that<br />

occur when using the transformed data are pointed out in [10].<br />

The three plots corresponding to the transformations in Table 6.1 are shown in Fig. (6.3) with<br />

the lowest concentration value as a green point. One might notice how the points are not regularly<br />

spaced, especially on the Lineweaver-Burk and Eadie-Hofstee plots. We explore these three<br />

methods simultaneously and their sensitivity to random and systematic error, both constant and<br />

proportional. If students need an introduction to investigating error, see [11, 12].


116 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 116–139<br />

Project Management Spreadsheet Gaming Application<br />

Wee Leong Lee<br />

School of Information Systems<br />

Singapore Management University, Singapore<br />

CHAPTER 7<br />

Address correspondence to: Dr. Wee Leong Lee, School of Information Systems, Singapore Management<br />

University, 80 Stamford Road, Singapore 178902; Tel: (+65) 6828-0937; E-mail: wllee@smu.edu.sg<br />

Abstract: This <strong>chapter</strong> seeks to illustrate how simple spreadsheets can be used creatively<br />

with amazing outcomes. This will be demonstrated through a project management<br />

game, built entirely using standard spreadsheet features and functions. The<br />

project management game is designed as a teaching tool to allow players to experience<br />

project management in an interactive and fun atmosphere. In the game, players<br />

learn to respond to unforeseen events, make appropriate decisions to resolve issues,<br />

keep the project team motivated, and take corrective measures to keep the project on<br />

track and on target. This <strong>chapter</strong> is aimed at providing an overview of the game, discussing<br />

how it should be played, and explaining the underlying principles behind the<br />

rules of the game. It is not meant to be technical, although some amount of logical<br />

relationship between variables and mathematical functions will be discussed.<br />

Keywords: project management, gaming applications.<br />

7.1 Introduction<br />

Spreadsheets were originally intended to help ease laborious accounting work but their applications<br />

have extended far beyond just crunching numbers, accredited to their versatility and ease of use.<br />

Today they have become one of the most commonly used applications both in school and at work.<br />

The use of spreadsheets as teaching tools has also gained popularity in recent years. Spreadsheets<br />

have been extensively applied to numerous fields, ranging from engineering, statistics, operations<br />

management, business modeling, and Monte-Carlo simulations [1–3].<br />

Microsoft Excel has been the predominant spreadsheet application for many years given the<br />

pervasive Microsoft Windows platform. The built-in VBA (Visual Basic for Applications) programming<br />

language in Excel has greatly enhanced its application beyond the normal usage of spreadsheets.<br />

Numerous games have been developed in Excel spreadsheets and are shared freely over the<br />

internet. In the course of developing a module in IT projects and vendor management, I looked at<br />

what has been done in this area using spreadsheets. I found numerous templates for project plan-<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Project Management Spreadsheet Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 117<br />

ning, budgeting, and Gantt charts. These templates although useful and easily adoptable with little<br />

training did not meet my expectations. I needed a more interactive application that could serve as<br />

a teaching tool to allow students to relate to project management concepts and best practices. My<br />

search was quite exhaustive but I was unable to find an application in Excel that suited my purposes.<br />

However, I did find some commercial websites selling project management simulation tools.<br />

Having evaluated some of these commercial project simulation tools, which are often complex, not<br />

user-friendly and costly, I shelved the idea of incorporating them for my course.<br />

Having taught a course (Computer as an Analysis Tool) which uses spreadsheets as problem<br />

solving and modeling tools over four years, I gathered I should have sufficient knowledge and skill<br />

sets to build an Excel-based project management game. I have never looked back. The process of<br />

building the game although agonizing at times has turned out to be a very fulfilling and enriching<br />

experience. Excel is an excellent tool for building an application quickly without messing with<br />

database, user-interfaces, and reporting tools. All these functionalities can be developed relatively<br />

easily in Excel albeit scalability could be an issue in the long run. The ease of creating user interfaces,<br />

rich library of mathematical functions, ease of storing and retrieving data (without having<br />

to handle large arrays), and simplicity of the coding in VBA programming language reduce the<br />

development effort considerably.<br />

A simulator is not to be confused with simulation. A simulator requires the user to respond<br />

interactively to requests and events in real-time and their responses to those requests and events<br />

will have consequences (e.g., a flight simulator). A simulation, on the other hand, usually requires<br />

the user to set up the initial simulation parameters before running the simulation. The outcomes<br />

can only be known after the simulation is completed and no action is needed while the simulation<br />

is running. The project management game I developed requires the player to set up a project plan<br />

(i.e., initial simulation parameters) before executing the plan (i.e., responding to changes). Project<br />

managers have to manage multiple performance indexes and make critical decisions to situations<br />

that often result in tradeoffs between the performance indexes. Unforeseen events beyond the control<br />

of project managers can occur that require good judgment and decision making in order to steer<br />

the project toward successful completion.<br />

The project management life cycle can be broadly categorized into three stages, namely, project<br />

planning, project execution, and control and project closing. Each stage is equally important to ensure<br />

project success although I chose to only focus on the project planning and project execution<br />

and control in the game to begin with. In this <strong>chapter</strong>, I will elaborate more on the planning stage<br />

while briefly touching on the execution and control stage. The <strong>chapter</strong> is not meant to be too technical,<br />

although some amount of logical relationship between variables and mathematical functions<br />

is discussed.<br />

7.2 About the Game: Structure and Features<br />

The project management game is designed as a teaching tool to allow players to experience project<br />

management in an interactive and dynamic environment. In the game, players learn to respond to<br />

unforeseen events, make appropriate decisions to resolve issues, keep the project team motivated,<br />

and take corrective measures to keep the project on track and on target. Throughout the gaming<br />

exercise, players get to appreciate and experience the complexity of project management in an


118 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Wee Leong Lee<br />

intense and yet exciting way, and learn the intricacies of managing project tradeoffs among budget,<br />

schedule, quality, and motivation.<br />

In the game players are to plan and manage a virtual IT project. The project consists of a series<br />

of interdependent activities and players would have to manage the completion of these activities<br />

while satisfying some performance criterion. There are two parts to this game. Firstly, players<br />

have to create a project plan by assigning suitable resources to a set of predefined activities. Upon<br />

completion of the initial project plan, which consists of building the project Gantt chart by assigning<br />

resources to activities, players shall advance to the second part, executing the project. Events and<br />

situations will emerge throughout the project execution and players have to exercise good project<br />

management skills and judgment to steer the project toward completion.<br />

The game hopes to achieve the following learning outcomes:<br />

• Understand the importance of effective resource planning in a project.<br />

• Understand the usage of basic project management tools (e.g., Gantt charts, network diagram,<br />

resource utilization).<br />

• Learn to execute a project effectively.<br />

• Make rational decisions and exercise good judgment under stress and time constraints.<br />

• Respond appropriately when faced with typical issues in project management.<br />

• Manage tradeoffs among different performance criteria.<br />

7.2.1 Game User Interface<br />

The main user interface (UI) screen of the game is shown in Fig. (7.1). This application was built<br />

in Excel 2007 utilizing only standard Excel features and functions and VBA without add-ins to<br />

minimize potential compatibility issues. The main UI consists of dials, indicators, and buttons. On<br />

the top left corner of the screen is a simulation clock (built using a pie chart) which starts operating<br />

only when project execution starts. The clock does not run during the project planning stage. A<br />

complete cycle of the clock represents one simulation day, which is around three minutes in real<br />

time. An indicator below the clock displays the current day. The first day of the project execution<br />

is set to January 1st, 2009.<br />

The decision score (DS) on the right of the UI shows the percentage of decisions made that<br />

were correct. The customer satisfaction index (CSI) shows the customer level of satisfaction on the<br />

project performance. The CSI is computed as a function of the performance index as well as the<br />

overall management of the project.<br />

The purple and orange buttons on the left of the UI leads to information about activities, employees,<br />

resource allocation, resource training, network diagram, resource Gantt chart, and schedule<br />

Gantt chart. The two green buttons are for making decisions and reading emails when prompted by<br />

the game controller (the game engine that controls the logic). The three light blue buttons off the<br />

center of the UI toward the right are for making adjustments to the project scope, setting quality<br />

review dates, and scheduling of meetings, and organizing activities. The four dark blue buttons<br />

are used for viewing historical performances of the four performance indexes during the game. The


140 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 140-158<br />

Teaching Portfolio Theory in an Equilibrium Setting<br />

with the Aid of Spreadsheet Tools<br />

Clarence C.Y. Kwan*<br />

DeGroote School of Business<br />

McMaster University, Hamilton, Ontario, Canada<br />

CHAPTER 8<br />

*Address correspondence to: Prof. Clarence C.Y. Kwan, DeGroote School of Business, McMaster University,<br />

1280 Main Street West, Hamilton, Ontario L8S 4M4, Canada; Tel: (+1) 905-525-9140, Ext. 23979; E-mail:<br />

kwanc@mcmaster.ca<br />

Abstract: Mean-variance portfolio theory being part of the core curriculum of modern<br />

finance in business education, this <strong>chapter</strong> presents an asset pricing model based<br />

on it in an equilibrium setting. Here, equilibrium pertains to matching of supply and<br />

demand of individual assets in an investment market for rational portfolio decisions.<br />

An example utilizing various Microsoft Excel features in matrix operations is provided<br />

to illustrate the computational task involved. This <strong>chapter</strong> is intended to make<br />

the model less abstract, thus complementing the textbook materials on the model.<br />

With computational issues no longer a concern, students can focus their attention on<br />

the concepts involved.<br />

Keywords: portfolio theory, capital asset pricing model, CAPM.<br />

8.1 Introduction<br />

Mean-variance portfolio theory is part of the core curriculum of modern finance in business education.<br />

The theory, which explains those concepts underlying portfolio investment decisions under<br />

risk – with risk represented by the variance of the probability distribution of rates of returns of the<br />

investment – has two complementary aspects. As normative theory, it provides criteria for investment<br />

decisions and stipulates rules for attaining the desired ends. By treating the estimated means,<br />

variances, and covariances from a multivariate probability distribution of returns on the individual<br />

financial assets considered as input parameters, it seeks to achieve optimal risk-return tradeoff in the<br />

allocations of investment capital under various constraints. This task is commonly called normative<br />

portfolio analysis or, simply, portfolio analysis. As positive theory, in contrast, portfolio theory<br />

attempts to explain and predict phenomena in investment markets. For example, it allows the collective<br />

investment decisions by participating investors to determine asset prices or expected returns,<br />

under the condition of matching supply and demand of financial assets in market equilibrium.<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved - © 2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Teaching Portfolio Theory Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 141<br />

Under some simplifying assumptions, such as risk-free lending and borrowing at the same interest<br />

rate and frictionless short sales of risky assets, the corresponding results of normative portfolio<br />

analysis are generally easy for students to follow. 1 The assumption of frictionless short sales is that<br />

the short seller not only provides no cash deposits for any borrowed assets, but also has immediate<br />

access to the short-sale proceeds for investing in other assets. Once the formulation for constrained<br />

optimization is in place, the portfolio allocation results will follow. 2 The use of electronic spreadsheet<br />

tools also helps greatly in reducing the computational burden and in making the analytical<br />

material involved less abstract to students. As illustrated in [2, 3], with the aid of Microsoft Excel<br />

features, to construct practically relevant portfolios without using multivariate calculus tools is also<br />

possible. 3<br />

The Capital Asset Pricing Model, which is also known simply as the CAPM, is the central<br />

result of portfolio theory. The model, which is based on the work of [4–6], is highly important in<br />

modern finance and thus is part of the core curriculum. As mentioned in most introductory finance<br />

textbooks, the model explains asset pricing in terms of the part of the risk that cannot be diversified<br />

away from portfolio investments. The Sharpe-Lintner version of the model in [4, 5] establishes, in<br />

market equilibrium, a tradeoff between the expected return of each asset and its non-diversifiable<br />

risk. Market equilibrium pertains to matching supply and demand of the individual assets. However,<br />

the Mossin version in [6] captures explicitly asset prices and the participation of individual investors<br />

in the model formulation; it allows asset prices instead of their expected returns to be determined.<br />

The CAPM covered in finance textbooks is the Sharpe-Lintner version. As asset prices are<br />

implied in the model by their expected returns, a typical question to the author (as an instructor<br />

of various finance courses in which the CAPM is taught) from students, especially those who are<br />

unaware of its derivation, is why it is called a pricing model when asset prices are not even there.<br />

Another typical question from students who have learned normative portfolio analysis is whether<br />

any expected returns, variances of returns, and covariances of returns are input parameters or results<br />

of the equilibrium analysis involved. Further, as the market portfolio – which is a portfolio of all<br />

risky assets in the market providing the best risk-return tradeoff – plays a crucial role in the CAPM,<br />

some students are also curious as to whether the risk preferences of investors in the market affect<br />

the risk premium of such a portfolio, in terms of its expected return in excess of the risk-free interest<br />

rate. These questions can be answered more easily if the derivation of the CAPM is based on an<br />

analysis where asset prices are explicitly considered.<br />

Drawing on [7], which is based on a similar idea of the Mossin version of the CAPM, this<br />

<strong>chapter</strong> derives an asset pricing model that is less abstract, from a pedagogic perspective. For<br />

students to understand fully the derivation, they must still have some prior knowledge of various<br />

economic, mathematical, and statistical topics. The statistical component of the task is generally<br />

familiar to business students the author has taught, and the idea of equilibrium analysis, though<br />

likely new to these students, is not complicated. The mathematical component of the task requires<br />

1 See, for example, Chapter 6 in [1].<br />

2 The assumption of frictionless short sales ensures that essential multivariate calculus tools are adequate for the analysis<br />

involved. If realistic short-sale transactions are to be captured or if short sales are disallowed, then the corresponding<br />

analysis will be much more complicated. See, for example, [2, 7] for analytical details.<br />

3 Specifically, [3] uses Excel Solver to construct efficient portfolios, thus bypassing the analytical details of the<br />

constrained optimization considered. In [2], where the analytical solutions are obtained by using algebraic tools instead,<br />

the computations involved are performed by using Excel functions for matrix operations.


142 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Clarence C.Y. Kwan<br />

the use of multivariate calculus for optimization and matrix algebra. For students who have learned<br />

normative portfolio analysis, however, such a task is not burdensome. Notice that the equilibrium<br />

analysis to be presented in this <strong>chapter</strong> is not intended to replace the textbook version. Rather, the<br />

two versions complement each other, so that students can better appreciate the various implications<br />

and limitations of the model.<br />

The matrix operations as required for the equilibrium analysis here are confined to matrix addition,<br />

multiplication, transposition, and inversion, as well as finding the determinant of a matrix. As<br />

spreadsheet tools for matrix operations are easy for students to learn, using them can significantly<br />

reduce the computational burden. With the relevant input parameters arranged as blocks of data in a<br />

spreadsheet, to perform matrix operations is straightforward. With computational issues no longer<br />

a concern, students can focus their attention on conceptual issues pertaining to the model.<br />

To facilitate the analysis that follows, Section 8.2 first provides some essential material on risk<br />

aversion. Section 8.3 starts with a basic equilibrium analysis for asset price determination. An<br />

extension of the analysis, by relaxing a simplifying assumption in the CAPM, is also considered.<br />

Implications of this extension are discussed as well. Section 8.4 presents an Excel example to<br />

illustrate the required computations. Section 8.5 offers some concluding remarks. For readers who<br />

are unfamiliar with the CAPM, the appendix at the end of this <strong>chapter</strong> provides an abbreviated<br />

version of its derivation in textbooks. 4<br />

8.2 Preliminaries<br />

Let U(W) be the utility function of an investor with wealth W. The investor is rational if the first<br />

derivative of U(W), written as U ′ (W), is positive. The idea is that, if wealth is the only factor in<br />

the determination of satisfaction, a rational investor must prefer more wealth to less wealth. The<br />

investor is also risk averse if the second derivative, U ′′ (W), is negative. The idea is that a risk<br />

averse investor considers the increase in satisfaction for having an incremental wealth ΔW less than<br />

the decrease in satisfaction for losing the same ΔW. To illustrate, if an investment has equal chances<br />

of gaining $h or losing $k, a risk averse investor will not find the investment worthwhile if h≤k;<br />

exactly how high h−k has to be for the investment to appeal to the investor depends on the function<br />

U(W).<br />

For a risk averse investor with an initial wealth W0, suppose that an investment will result<br />

in W0+z as the final wealth for the investor, with the outcome of the investment z being random.<br />

To assess the investment, the investor considers the expected utility of all potential outcomes,<br />

E[U(W0+z)]. Here, E[·] represents the expected value of the variable[·] in question. To the investor,<br />

this risky investment is equivalent to a risk-free investment with a certain outcome of E[z]−π,<br />

where π > 0 can be viewed as a premium that the investor is willing to pay in order to avoid risk.<br />

To determine π, we can start with<br />

U(W0+ E[z]−π)=E[U(W0+z)] (8.1)<br />

where W0+ E[z]−π is called the certainty equivalent wealth, CEQ.<br />

4 See, for example, Chapter 6 in [8].


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 159–172 159<br />

CHAPTER 9<br />

Forecasting with Innovation Diffusion Models: An Updated Example<br />

from the Telecommunications Industry 1994-2009<br />

John F. Kros 1,∗ and S. Scott Nadler 2<br />

1 Department of Marketing and Supply Management<br />

East Carolina University, Greenville, North Carolina, USA<br />

2 College of Business<br />

University of Central Arkansas, Conway, Arkansas, USA<br />

∗ Address correspondence to: Dr. John F. Kros, Department of Marketing and Supply Management, College<br />

of Business, East Carolina University, 3121 Harold Bate Building, Greenville, North Carolina 27858, USA;<br />

Tel: (+1) 252-328-6364; E-mail: krosj@ecu.edu<br />

Abstract: Managers have long been concerned about new product development<br />

and the life cycle of these products. Because many products do not sell at constant<br />

levels throughout their lives, product life cycles must be considered when developing<br />

sales forecasts. Innovation diffusion models have successfully been employed to<br />

investigate the rate at which goods and/or services pass through the product life<br />

cycle. This research investigates innovation diffusion models and their relation to<br />

the product life cycle. The model is developed and then tested using modem sales<br />

from 1994–2009. Each successive generation of modem innovation, from 14.4k,<br />

28.8k, 56k, broadband less than 3.6Mbps, to broadband greater than 3.6Mbps, is<br />

examined.<br />

Keywords: innovation diffusion model, forecasting, logistic growth model.<br />

9.1 Introduction<br />

The generation of new product opportunities has been a major area of study in both the academic<br />

and practitioner literature for decades. Products are born, grow to maturity, and are then either<br />

reinvented or die. During this ongoing process some products are cast aside by a changing society<br />

as consumer’s needs and wants change. Business managers are an integral part of this cycle which<br />

is commonly referred to as the product life cycle (PLC) [1].<br />

The PLC is made up of four distinct stages (see Fig. (9.1)). These stages include: introduction,<br />

growth, maturity, and decline.<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


160 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Kros and Nadler<br />

Fig. (9.1): Product life cycle.<br />

During the introduction stage of the PLC the firm’s primary goal is to get the technology into the<br />

customers’ hands. Growth during the introduction stage of the PLC is generally slow. The second<br />

or growth stage of the PLC is characterized by its rapid growth as consumers accept the product.<br />

During the maturity stage of the PLC sales reach the maximum point and the rate of adoption begins<br />

to fall. In the final stage of the PLC (decline) sales begin to decline significantly as customer needs<br />

change and they begin adopting newer technologies [1].<br />

An important aspect of the PLC is the rate at which consumers adopt a given product or technology.<br />

There are five categories of adopters. These categories include innovators, early adopters,<br />

early majority, late majority, and laggards.<br />

1. Innovators comprise approximately 2.5% of adopters. This group is generally younger and<br />

more accepting of new technologies.<br />

2. The second category of adopters is commonly referred to as early adopters. Early adopters<br />

make up approximately 13.5% and are important because they are known for seeking out new<br />

technologies.<br />

3. The third category (early majority) accounts for 34% of the market. The early majority are<br />

known for being neither the first or last to adopt a new product or technology. Products or<br />

technologies that have gained acceptance by early majority can no longer be considered new<br />

as their presence is a known quantity.


Forecasting with Innovation Diffusion Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 161<br />

4. The fourth or late majority stage makes up another 34% of the market. Late majority adopters<br />

do not adopt products until after all risks have been identified and when the adoption becomes<br />

an economic necessity or when there is social pressure to adopt.<br />

5. The fifth and final stage, which accounts for the final 16% of the market are commonly<br />

referred to as laggards. Laggards frequently wait to adopt a new technology until the next<br />

technology generation has entered the market.<br />

Fig. (9.2) provides a graphic representation of the adopter categories [2].<br />

Fig. (9.2): Distribution of adopter categories.<br />

The constant examination of products as they move through their life cycles is crucial to a firm’s<br />

success. Managers are challenged with developing new strategies, examining ongoing strategies,<br />

and eliminating non-competitive strategies for a product’s diffusion into markets. Many times it is<br />

the primary job of the operations and marketing managers to forecast a product’s diffusion. Within<br />

the business discipline the product life cycle and forecasting can be linked using what is called<br />

innovation diffusion theory [3].<br />

Innovation diffusion theory has received considerable attention since its inception in the 1960’s.<br />

The diffusion of innovation can be defined as the process by which an innovation is imparted on<br />

members of society through certain channels over time [4]. Seminal works in the area of technological<br />

change and rates of imitation were completed by Fourt [5] and Mansfield [6]. A detailed<br />

discussion of using diffusion models in product forecasting can be found in [7]. The work by<br />

Fourt [5] and Mansfield [6] are the basis for research in diffusion modeling by Bass [8].<br />

The Bass model for new product growth and innovation diffusion has been used to forecast<br />

numerous products in many different industries [5, 6, 8–13]. A comprehensive review of the contributions<br />

to this literature through the 1970’s is provided in [14] and on into the 1980’s in [15].<br />

An excellent article comparing nine growth and innovation diffusion models, including Mansfield’s<br />

and Bass’ models, can be found in [13]. The influence of information technology diffusion on large<br />

and small businesses is discussed in [9, 10]. Additional insights are provided in [16–20].<br />

This <strong>chapter</strong> extends the work by [21] to the original Mansfield model applied to the technology<br />

industry where successive generations of the technology exist. The model is developed and then<br />

tested using modem sales from 1994-2009. The diffusion model is applied to each successive<br />

generation of modem innovation: 14.4k, 28.8k, 56k, broadband < 3.6Mbps, and broadband ><br />

3.6Mbps. Two forecasting models for the > 3.6Mbps technology are developed, analyzed, and<br />

reported on.


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 173–240 173<br />

School Mathematics with Excel<br />

Jan Benacka<br />

Department of Informatics<br />

Constantine the Philosopher University, Nitra, Slovakia<br />

CHAPTER 10<br />

Address correspondence to: Dr. Jan Benacka, Department of Informatics, Faculty of Natural <strong>Science</strong>s,<br />

Constantine the Philosopher University, Tr. A. Hlinku 1, SK-94974 Nitra, Slovakia; Tel: (+421) 37-6408-<br />

678; E-mail: jbenacka@ukf.sk<br />

Abstract: The use of computers is pervasive in education at both the secondary and<br />

university levels. Learner-oriented computer programs have the potential to motivate<br />

students to learn mathematics. One such computer program is Microsoft Excel,<br />

which for many years has been embraced by educators as the ideal platform for<br />

providing students with hands-on activities that enhance their learning. By design,<br />

Excel (or spreadsheets in general) lends itself to transparent problem formulation<br />

and minimal programming requirements.<br />

In this <strong>chapter</strong> I will present several spreadsheet applications that I have developed<br />

over the years. The applications are aimed at introducing concepts in the teaching<br />

of mathematics at the secondary level and introductory calculus as well.<br />

Keywords: calculus, linear algebra, Euclidean geometry, stereometry.<br />

10.1 Introduction<br />

During my 14 year teaching practice at grammar school (ages 15–19) where I taught mathematics,<br />

physics, and informatics in common, mathematical, and informational classes, I started developing<br />

spreadsheet applications for visualizing mathematical relationships. I have developed the following<br />

sets of applications:<br />

• Elementary functions<br />

• General functions and calculus (derivatives, integrals, and so on)<br />

• Equations, inequalities without a parameter<br />

• Equations, inequalities with a parameter<br />

• Systems of linear equations<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


174 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Jan Benacka<br />

• Complex numbers<br />

• Analytical geometry of linear figures in E2 and E3<br />

• Analytical geometry of quadratic figures in E2 (conic sections, also versus line)<br />

• Stereometry (sections of cubes, cuboids, prisms, and pyramids; distances and angles of lines<br />

and planes within these bodies)<br />

• Functions of two variables<br />

I have tried the applications at various schools of secondary and university level with very positive<br />

responses from the students and teachers – some of them were entranced by the possibilities of<br />

Microsoft Excel and the simplicity of use of the applications. In this <strong>chapter</strong> I present several<br />

examples, some of which may be implemented in 5 minutes each provided the student is skilled in<br />

spreadsheets. In the next sections I will describe eight sets of these from a usage viewpoint. The<br />

skills required for the applications are:<br />

(a) writing in the equation of a function,<br />

(b) fill down, fill right,<br />

(c) copy formulas into the cells,<br />

(d) making use of Goal Seek and Solver,<br />

(e) adjusting axis ranges and units.<br />

Action (a) cannot be made by a macro. Actions (b) and (c) can be combined together by a macro<br />

activated by, say, a button. I think I will pursue this approach in my future work. Action (d) can<br />

be automated by a macro if a value close to the solution is added in a cell; however, I regard Goal<br />

Seek and Solver so essential in math, useful and easy to use that I will not explore this alternative.<br />

Action (e) is performed by a macro in various ways in the applications. The axis ranges and units<br />

are adjusted automatically after inputting the values in cells “xmax”, “xmin”, “ymax”, and “ymin”<br />

in the charts in Sections 10.2.2 and 10.2.3. Shifting the coordinate system in the left-right or up-left<br />

direction is possible in Sections 10.4.1 and 10.4.2. Diminishing or enlarging the scene is possible<br />

in all charts.<br />

10.2 Functions, Calculus, Equations, Inequalities, and Linear Systems<br />

10.2.1 Elementary Functions<br />

Elementary functions are a significant part of mathematics curriculum in school. Students study the<br />

properties of the graphs, the relations between the parameters and the graph, and so on. The curriculum<br />

starts with the linear and quadratic functions. Then, there is the linear fractional function,<br />

integer power function, square root function, exponential and logarithmic function, and trigonometric<br />

functions.


School Mathematics with Excel Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 175<br />

To draw the graph of a function by hand, students usually make a table of (x,y) pairs, where<br />

x goes from about −5 to 5 in increments of 1 and y is calculated according to the equation of the<br />

function. Then they draw the (x,y) points in xy coordinate system, and draw the graph through the<br />

points. The accuracy and aesthetic level are minimal. The graphs are static and do not enable students<br />

to experiment. However, there is a simple tool for making the same more quickly, accurately,<br />

and at a high aesthetic level – the spreadsheet program. Spreadsheet graphs can easily be made interactive,<br />

which enables students to experiment with the inputs. Once the application is ready, it can<br />

be saved and used any time the user needs to study it. In this way, a set of ready-to-use applications<br />

can be made, one for each elementary function, thus saving valuable time since the user does not<br />

have to spend effort in creating these applications. The necessary skills can be found in [1, 2].<br />

In this <strong>chapter</strong>, a set of ready-to-use applications for teaching and learning elementary functions<br />

is presented. I developed them during my 14-year experience in teaching the topic at grammar<br />

school. There is an application for each elementary function. The models do not require any prior<br />

knowledge of the applications; the only task is just inputting the parameters, which makes them<br />

convenient for immediate integration into the teaching process in school as well as learning at home.<br />

The models enable the user to reveal the meaning of the parameters, find the relations between them<br />

and the graph, and comprehend it. The possibility of free experimentation due to interactivity and<br />

simplicity of the models makes them ideal tools for getting the graphs and the meaning of the<br />

parameters in the user’s visual memory, which is crucial for understanding compound functions<br />

and calculus. Compared to mathematical software and graphical calculators, the advantage of the<br />

set is the readiness to use – no skills are required, and Excel is widely available in schools as well<br />

as at home (see [3]).<br />

10.2.1.1 The Applications<br />

The applications are depicted in Fig. (10.1)–(10.4). All applications have the same design. In the<br />

center, there is a chart with the graph in red. The translated axes x ′ and y ′ are given by the equations<br />

y=n and x=m, respectively, and are indicated by blue lines. The chart area, that is, the axes range,<br />

is [c,c]×[c,c], where c is 5, 10, 25, or 50, and it is governed by the slider in range “Graph”. The<br />

input parameters are in the white cells. The position of the parameters in the function formula is<br />

clear from the definition in the chart header. The forbidden parameter values are announced along<br />

with the definition domain. If a forbidden parameter value is inputted, the case is written in bold<br />

red below the inputs, e.g., a=0 in a quadratic function or ad = bc in a linear fractional function.<br />

The gray cells contain formulas that are protected against rewriting. Range “Graph” comprises the<br />

(x,y) pairs that give the graph. The equation y= const is solved automatically in range “Find x”<br />

if the user inputs the number const into the white cell. Finding the zero point of the function only<br />

requires inputting 0 into the cell. This allows immediate solutions to inequalities y≥0 (>, ≤,


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 241–260 241<br />

Graduates’ Use of Technical Software in Financial Services<br />

Timothy Kyng, 1 Leonie Tickle, 1 and Leigh Wood 2,∗<br />

1 Department of Actuarial Studies<br />

Macquarie University, New South Wales, Australia<br />

2 Faculty of Business and Economics<br />

Macquarie University, New South Wales, Australia<br />

CHAPTER 11<br />

∗ Address correspondence to: Dr. Leigh Wood, Faculty of Business and Economics, Room 714, Bldg. E4A,<br />

Macquarie University, NSW 2109, Australia; Tel: (+61) 2-9850-4756; E-mail: leigh.wood@mq.edu.au<br />

Abstract: A university education in actuarial studies and related areas prepares<br />

graduates for a wide range of careers. This study demonstrates that recent graduates<br />

working in the financial services industry make significant use of spreadsheet<br />

software. We found that all 76 respondents use spreadsheet software, and more than<br />

half spend at least 60% of their time using spreadsheets. Graduates also use a range<br />

of statistical, database, mathematical, financial, and actuarial software. This significant<br />

time spent in front of the computer has implications for universities wishing to<br />

design curriculum to prepare students for careers in the financial services industry.<br />

Keywords: technical software usage, financial service.<br />

11.1 Introduction<br />

The transition to employment after university study is an area of increasing interest for universities.<br />

University degree programs are judged, in part, on the ability of their students to find employment.<br />

The Graduate Destination Survey [1] is an Australia-wide survey used to track the employment of<br />

graduates six months after they complete their studies. The surveys show that employment in the<br />

finance industry is consistently high with good starting salaries.<br />

For the continuing success of graduates entering the finance industry, it is important for universities<br />

to listen to graduates and their employers to ensure that university learning is appropriate<br />

and relevant. Of course, the role of universities is broader than the immediate needs of industry and<br />

the needs of a graduate on day one of a position in finance. A university degree prepares graduates<br />

for a range of careers over their lifetime, and provides a foundation in the pursuit of learning for its<br />

own sake.<br />

In Europe, the Tuning Report [2] found high levels of agreement about outcomes between<br />

students, graduates and industry, and less agreement with academics. Our study fits into this gap<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


242 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Kyng et al.<br />

between industry and the curriculum that delivers graduates to industry. Earlier studies [3, 4] found<br />

that graduates in the finance industry wanted more learning of software tools at university. In this<br />

study we focus on the in-depth use of software in the finance industry to enable universities to<br />

ascertain the potential benefits of including such software in the curriculum. We investigate the use<br />

of software by recently hired graduates working in the areas of banking, finance, insurance, and<br />

financial risk management.<br />

11.2 Background<br />

The use of software in university education can serve two purposes: it can enhance learning of<br />

concepts; and it can familiarize students with specific software that they will later use in their<br />

working lives.<br />

Recent research points to the effectiveness of software in achieving the first of these aims – enhancing<br />

student learning. Wagner [5] observed significant improvements in problem-solving across<br />

several numeric tasks among engineering students exposed to Excel and related programs. Johnson<br />

[6] claims that use of spreadsheets facilitates hypothesis testing, the investigation of variants<br />

and algebraic reasoning. A significant amount of literature suggests that spreadsheets allow users<br />

the opportunity to increase the scope of their respective roles. Holton [7] suggests that such applications<br />

allow users to recognize patterns “if they are not tied down with interminable calculation<br />

that they may or may not do correctly.” Although he particularly discusses integrating spreadsheet<br />

applications into tertiary mathematics education, there is certainly scope to transfer the concept to<br />

the financial sector and the role of financial graduates. Similarly, Lavicza [8] points out that “computers<br />

were originally invented to enhance and accelerate tedious mathematical operations” and<br />

Forster [9] adds that “passing mathematics processing to a technology allows students to focus on<br />

mathematics properties and relationships, provided that technical expertise is in place.” Togo and<br />

McNamee [10] concur, pointing out that spreadsheets allow users the opportunity to master “the<br />

problem process rather than obtaining a solution to a specific problem.” Marriott [11] also emphasizes<br />

that the “integrative use of spreadsheets as a computational tool serves to focus on higher-level<br />

learning skills.”<br />

The second purpose of the use of software in university education – to provide students with<br />

specific software that they may later use at work – has not been comprehensively studied across<br />

all areas of the financial sector. The majority of studies are of accounting graduates with very few<br />

studies of graduates in finance: the literature is reviewed in the following sections. While there is<br />

some overlap in the use of technical software, industry specific studies, such as the one reported<br />

in this <strong>chapter</strong>, are of more assistance in designing curricula for graduates moving into specialized<br />

industries.<br />

Spreadsheets are the most common application used by recent graduates in the financial sector.<br />

This has been true for a number of decades, even while we have seen accounting information<br />

systems “undergo extensive change in the past 35 years” [12]. Waller and Gallun’s study of 36<br />

accounting organizations in 1985, including the ‘big eight’, discovered a “predominance of spreadsheet<br />

applications” being used in the financial sector (cited in [13]). Almost 15 years later, just<br />

before the turn of the millennium, “spreadsheets remain at the forefront of accountancy work practices<br />

and are used on a daily basis by most accountants” [14]. Recently, Kyng and Taylor [4] report


Graduates’ Use of Technical Software Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 243<br />

that “the use of spreadsheets in the workplace is ubiquitous,” with 80% of their respondents rating<br />

them “very important” to “essential.” Despite this broad use, only 30% of managers indicate<br />

that they provide a basic training course, expecting “staff to learn on the job from colleagues or to<br />

already have these skills before joining the organization” [4].<br />

Aside from spreadsheets, Larres and Oyelere [14] suggest a number of other technical software<br />

tools that workers in the finance sector are familiar with: these include, to varying extents, integrated<br />

accounting packages, word processing packages, and database creation and manipulation packages.<br />

Mohamed and Lashine [15] consider the importance of a multifaceted graduate, noting that “the use<br />

of information technology, in particular, processing and communication information has become an<br />

essential need. Knowledge of some accounting packages is no longer a plus; it is a must.” More<br />

recently, Murray et al. [16] consider the following IT applications as most important for finance<br />

graduates to possess: Microsoft Office, Internet browser, Enterprise Systems, Instant Messaging,<br />

Windows, Project Management Software, and Modeling Software (e.g., Microsoft Visio).<br />

Some of the literature reviewed here does not reflect the influence of technical software, including<br />

spreadsheets, in finance in 2010. In addition, the requirements of recent graduates are rarely<br />

investigated. In the next section we will present the results of our survey of the use of software<br />

among graduates working in the financial services industry.<br />

11.3 Methodology<br />

There is a clear gap in our understanding of the use of technical software by graduates working in<br />

financial services. The methodology chosen was an in-depth online survey of recent graduates. The<br />

survey (see the appendix at the end of this <strong>chapter</strong>) was comprehensive and designed to ascertain<br />

graduates’ use of various types of technical software used for financial and statistical analysis and<br />

modeling. The Institute of Actuaries of Australia (IAAust) advertised the study to its members,<br />

and the authors contacted industry colleagues directly to invite them to participate. Recent students<br />

who had completed postgraduate courses run by Macquarie University for the IAAust were also<br />

invited to participate. Most, but not all, of those contacted were members of the IAAust. Members<br />

of the IAAust work in a wide range of jobs throughout the financial services industry, not just<br />

in the traditional areas of life insurance and pension planning (superannuation). There were 76<br />

respondents to the online questionnaire.<br />

11.4 Results<br />

11.4.1 Demographic and Work Characteristics<br />

The demographic characteristics of the 76 respondents are shown in Table 11.1. Almost two-thirds<br />

of respondents are male, and 90% are aged under 30. Two-thirds of the respondents have been in<br />

the workforce for three years or less, and 95% for five years or less.


Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 261–273 261<br />

Professional Development in Electricity Markets<br />

with Spreadsheet Models<br />

Elliot Tonkes<br />

Director of Risk and Analytics<br />

Energy Edge Pty Ltd, Brisbane, Australia<br />

CHAPTER 12<br />

Address correspondence to: Dr. Elliot Tonkes, Energy Edge Pty Ltd, PO Box 10755, Brisbane QLD 4000,<br />

Australia; Tel: (+61) 0407-659-625; E-mail: etonkes@energyedge.com.au<br />

Abstract: This <strong>chapter</strong> presents a case study illustrating the physical dispatch algorithm<br />

used by Australia’s electricity market operator (AEMO) to determine which<br />

power plants to dispatch into the grid and the resultant electricity spot price. The<br />

models are similar to case studies applied by the author in professional development<br />

for training a disparate audience about the nature of the deregulated Australian National<br />

Electricity Market (NEM). This <strong>chapter</strong> addresses the particular experiences<br />

of the author in delivering professional development education to an area of industry<br />

focusing in energy and finance. It has been found that the commonality amongst a<br />

diverse range of workshop participants is their understanding of Excel, and it forms<br />

an ideal mechanism to communicate technical and mathematical concepts. Although<br />

highly simplified, the implementation exhibits the key concepts of price-setting and<br />

dispatch instructions in the Australian electricity market (NEM).<br />

Keywords: National Electricity Market (NEM), dispatch algorithm.<br />

12.1 Introduction<br />

There is a vast body of literature produced in the academic arena relating to the theory and experiences<br />

of education in primary, secondary, and tertiary environments. However, publications<br />

devoted to issues in Professional Development (PD) are much rarer. The author has been involved<br />

in industry, tertiary education, and delivery of professional development, and this <strong>chapter</strong> is aimed<br />

at conveying the experiences and enlightening the audience about the use of spreadsheets in professional<br />

development for a particular specialization of industry.<br />

The author is a founding member of a firm Energy Edge which consults to industry on financial<br />

management in the energy sector. In particular, Energy Edge has a focus on electricity markets,<br />

and particular expertise in derivative pricing and portfolio risk management. The business activities<br />

of Energy Edge also extend to training market participants and parties such as bankers, financiers,<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


262 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Elliot Tonkes<br />

investment firms, and trading houses. The attendees at our courses span a wide range of employment<br />

positions, ranging from traders, to market analysts, to engineers and accountants. In common across<br />

all of the attendees is a need to understand how the market works in a qualitative and quantitative<br />

sense.<br />

Inevitably, mathematical, technical, and algorithmic concepts arise in the delivery of the workshop<br />

syllabus. The mathematical abilities of the audience cover a wide spectrum of sophistication.<br />

However, our experience is that workshop attendees are universally familiar with spreadsheets.<br />

With spreadsheet software as a modeling platform, we are able to construct simple models to convey<br />

complex concepts.<br />

The objectives of the present <strong>chapter</strong> are twofold. Firstly, I will convey experiences in delivering<br />

professional development education and make comparisons with pedagogy for tertiary education.<br />

Secondly, this <strong>chapter</strong> will introduce a modeling problem in the electricity market and illustrate<br />

how it has been used in the delivery of professional development workshops.<br />

The author has developed several spreadsheet models which have proven useful in conveying<br />

key concepts of the NEM in professional education courses. This <strong>chapter</strong> outlines the use of spreadsheets<br />

to illustrate the NEM dispatch algorithm, and how traders and managers can experiment with<br />

the models to better understand the NEM and to improve their business practices.<br />

12.2 The Professional Development Audience<br />

The use of spreadsheets throughout industry is possibly far more pervasive that researchers in the<br />

educational arena suspect [1]. From the observations of the author in the finance and energy industries,<br />

Microsoft Excel is an invaluable form of communication between professionals to convey<br />

results, to communicate illustrative models, and transport and display summary (and detailed) data.<br />

In many instances, full blown production software systems have been implemented in spreadsheets<br />

for management of financial and physical operations.<br />

Key to the utility of Excel is that spreadsheets are ubiquitous across different disciplines: accountants<br />

build financial models and budgets, traders keep track of forecasts and portfolio positions,<br />

and engineers and operational personnel use spreadsheets for modeling physical processes.<br />

PD workshops delivered by Energy Edge provide training to personnel from all of these disciplines.<br />

A primary objective of the various workshops which we deliver is to provide distilled<br />

information about a broad array of market topics to a motivated audience in a very limited time<br />

frame (typically a one day course). Therefore, our mechanisms of presentation have been refined<br />

to deliver a large volume of information in a digestible form. The audience demands information<br />

which is relevant and directly applicable to their business activities. Our particular syllabus aims<br />

to provide participants with exposure to how and why the market operates, to introduce standard<br />

market modeling methods, and to arm participants with information to know which way to turn for<br />

the next level of detail.<br />

Many of these features are evident in recent trends in tertiary education [2, 3], but PD time<br />

frames are even more compressed and relevance to industry further honed. PD frequently contains<br />

no assessment component, which ironically provides flexibility to the presenter to concentrate on<br />

elements which are most relevant to the audience as the workshop proceeds. Participants claim<br />

accredited training hours to maintain professional certification.


Professional Development in Electricity Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 263<br />

Throughout industry the role of Professional Development varies widely. Some PD workshops<br />

are focused to provide training on very particular technical aspects in great depth, for example,<br />

training on proprietary modeling software. Nevertheless, the industry audience demands concentrated<br />

information delivery with a focus on adding value to business and with a delivery mechanism<br />

which provides users with resources to help them when they return to their place of work [2].<br />

Compared with tertiary education, there is only limited time and desire for delving into theory,<br />

equations, and developing software models. However, a workshop running pre-canned models, or<br />

even worse, slide shows of model outputs disengages the audience quickly. We successfully integrated<br />

spreadsheet models with a mixture of pre-built modeling (to assist with rapid delivery),<br />

in-situ formula development (to demonstrate model construction), and running computational experiments<br />

(to convey the mechanics of the market and to illustrate behavioral impacts).<br />

Other authors in the academic arena have performed modeling of deregulated physical electricity<br />

markets with spreadsheets and other modeling software. Cau et al. [4] have instituted a teaching<br />

tool to highlight the gaming behavior of participants in the spot market. Their software implemented<br />

a physical market clearing model to establish spot prices and dispatch instructions. The scope of<br />

their curriculum concentrates on audience participation in extended experimental games to establish<br />

the behavioral characteristics of the spot market. Farr et al. [5] successfully used spreadsheet<br />

teaching models for an auction process associated with an alternative formulation of a deregulated<br />

electricity market.<br />

12.3 Mechanics of the National Electricity Market<br />

Australia’s National Electricity Market (NEM) is a real-time market for balancing the supply and<br />

demand of energy in Eastern Australia. It is a highly complex environment with many power stations<br />

contributing to an interconnected grid, a fine resolution time-scale, a multitude of engineering<br />

constraints and with many regulatory structures [6].<br />

The market is managed by a single market operator (AEMO) who is charged with implementing<br />

the very strict regulatory environment of the National Electricity Law. The market structure is quite<br />

different to typical equity or commodity markets owing to the peculiar nature electrical energy as<br />

the commodity being traded.<br />

At any point in time, the demand and supply must perfectly match for otherwise load shedding<br />

occurs which is deemed as a market failure under the market operator’s charter. Electricity cannot<br />

be effectively stored by either consumers or producers, and consequently the market is structured to<br />

accommodate a commodity which is undergoing continuous delivery and consumption. The NEM<br />

is structured as an interval market, where a new price is set, and new instructions to generators are<br />

produced at regular epochs (every five minutes). It is the role of the market operator to establish<br />

the clearing price (the spot price) and to issue instructions to the pool of generators (around 300<br />

generating units) for their individual levels of production.<br />

The market is structured as a gross pool market, meaning that generators are regulated to sell<br />

production solely to the central clearing house and all retailers buy from the same exchange. A<br />

single clearing price emerges (the spot price or pool price) and all participants are exposed to the<br />

same market price. A separate derivative market has emerged for participants to manage their pool<br />

price exposure.


274 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool, 2011, 274–279<br />

ARA, 143, 144<br />

CEQ, 142–144, 149<br />

absolute risk aversion, see ARA<br />

absurdity, see contradiction<br />

acceleration, 32–35<br />

activity network diagram, see project<br />

actuary, 241–253<br />

adopter category, see product<br />

AEMO, 261, 267<br />

algorithm<br />

division, 65<br />

Euclid’s, 67<br />

Euclidean, 82<br />

analysis<br />

beam, see beam<br />

data, 107<br />

equilibrium, 150<br />

fault, see fault analysis<br />

modal, see modal analysis<br />

regression, see regression<br />

structural, see structural analysis<br />

wall-frame, see wall-frame<br />

analytical geometry, see geometry<br />

arithmetic sequence, see sequence<br />

Australian national electricity market, see NEM<br />

Australias electricity market operator, see AEMO<br />

balanced fault, see symmetrical fault<br />

beam<br />

analysis, 20–25<br />

cantilever, 20–23, 25<br />

deflection, 22, 25<br />

determinate, 23, 25<br />

indeterminate, 25<br />

simply-supported, 23, 25<br />

beam deflection, see beam<br />

SUBJECT INDEX<br />

bending moment, see moment<br />

binomial equation, see equation<br />

boundary value problem, see BVP<br />

bus, 6<br />

admittance matrix, 6, 7, 9<br />

impedance matrix, 6, 7, 9<br />

voltage, see voltage<br />

BVP, 45, 46<br />

calculus, 179<br />

cantilever beam, see beam<br />

capital asset pricing model, see CAPM<br />

CAPM, 141, 142, 147, 150, 154<br />

catalysis<br />

homogeneous, 108<br />

central difference method, see difference<br />

certainty equivalent wealth, see CEQ<br />

chemical kinetics, see kinetics<br />

Chinese remainder theorem, see CRT<br />

circle, 215, 217, 224<br />

complex number, see number<br />

conditional formatting, 79, 80, 271<br />

congruence, 66, 76, 77, 79<br />

conic, 215, 216, 225<br />

constant<br />

binding equilibrium, 111<br />

dissociation equilibrium, 111<br />

context, 84<br />

contradiction, 95<br />

convolution, 32<br />

correlation matrix, see matrix<br />

cost functional, 41, 43, 45, 51<br />

covariance matrix, see matrix<br />

CRT, 78, 80<br />

CSI, see index<br />

current, 4<br />

load, 4<br />

Mark Lau and Stephen Sugden (Eds)<br />

All rights reserved – c○2011 <strong>Bentham</strong> <strong>Science</strong> Publishers Ltd.


Subject Index Applications of Spreadsheets in Education The Amazing Power of a Simple Tool 275<br />

phase, 4, 13, 14<br />

customer satisfaction index, see index<br />

decision score, see score<br />

definite integral, see integration<br />

degree of freedom, see system<br />

delay factor, 164<br />

difference<br />

central, 19, 32, 33<br />

equation, 85, 89, 90, 108<br />

linear, 85<br />

first, 89<br />

second, 85, 87, 89, 97<br />

difference equation, see difference<br />

differential equation, see equation<br />

diffusion, see model<br />

Diophantine equation, see equation<br />

Dirac-delta, 32<br />

dispatch algorithm, 262, 267<br />

displacement, 32–34<br />

displacement vector, see wall-frame<br />

division algorithm, see algorithm<br />

double line-to-ground fault, see unsymmetrical<br />

fault<br />

drift matrix, see wall-frame<br />

drift vector, see wall-frame<br />

DS, see score<br />

Duhamel integration method, see integration<br />

dynamic matrix, see matrix<br />

dynamic model, see system<br />

Eadie-Hofstee, see equation<br />

earthquake, 32<br />

efficiency index, see index<br />

eigensolution, 35, 37, 38<br />

eigenvalue, 20, 35, 37<br />

eigenvector, 20, 37<br />

elementary function, see function<br />

ellipse, 215, 218, 219, 222, 224<br />

enzyme, 108, 109, 111, 114<br />

enzyme kinetics, see kinetics<br />

enzyme reaction, see reaction<br />

equation, 183, 184<br />

binomial, 187<br />

difference, see difference<br />

differential, 42<br />

Diophantine, 101<br />

Eadie-Hofstee, 109, 110, 112<br />

Lineweaver-Burk, 109, 110, 112<br />

Michaelis-Menten, 108–111, 114<br />

Pythagorean, 99<br />

Woolf Hanes, 110, 112<br />

equilibrium analysis, see analysis<br />

error<br />

experimental, 107, 114<br />

mean absolute (MAD), 165<br />

random, 110<br />

simulation, 110<br />

systematic, 110<br />

constant, 109, 110<br />

proportional, 109, 110<br />

ETABS, 29, 31, 32<br />

Euclidean algorithm, see algorithm<br />

Excel<br />

ABS, 60<br />

ADDRESS, 80<br />

Application.OnTime, 129<br />

COUNTIF, 79<br />

Copy, 8, 33, 37, 47, 53<br />

FLOOR, 102<br />

Fill, 19, 20<br />

GCD, 193<br />

Goal Seek, 174, 179, 183, 184, 186, 203,<br />

211, 212, 218, 220<br />

IF, 88, 188, 215<br />

INDIRECT, 80<br />

INT, 92, 102<br />

MATCH, 80<br />

MDETERM, 151<br />

MINVERSE, 7<br />

MMULT, 154<br />

Max, 33<br />

Min, 33<br />

OFFSET, 268<br />

RANK, 268<br />

SUMIF, 271<br />

Solver, 42, 46, 49, 52, 54, 60, 107, 111, 112,<br />

165, 168, 174, 179, 181, 230


276 Applications of Spreadsheets in Education The Amazing Power of a Simple Tool Lau and Sugden<br />

TRANSPOSE, 154<br />

VLOOKUP, 208, 268, 271<br />

Excelet, 107–109, 112, 114<br />

excluded middle, 95<br />

experimental error, see error<br />

fault analysis, 3–14<br />

Fibonacci number, see number<br />

first difference, see difference<br />

flexibility matrix, see matrix<br />

force<br />

point, 20, 23, 25<br />

reaction, 22, 23, 25<br />

shear, 20–23, 25<br />

vector, 28, 29<br />

forecasting<br />

model, 161<br />

product, 161<br />

sales, 159<br />

frame deflection, see wall-frame<br />

function<br />

elementary, 174<br />

general, 179, 180<br />

utility, 142, 143<br />

function of two variables, see function<br />

Gantt chart, 117, 118, 120, 123, 125, 132<br />

general function, see function<br />

generalized frame, see wall-frame<br />

generator, 5<br />

geometry<br />

analytical, 209, 226<br />

greatest common divisor, see gcd<br />

Hamiltonian, 43, 45, 54<br />

homogeneous catalysis, see catalysis<br />

hyperbola, 215, 216, 219, 224<br />

indeterminate beam, see beam<br />

index<br />

customer satisfaction (CSI), 118<br />

efficiency, 128<br />

performance, 118, 119, 132<br />

induction<br />

mathematical, 90, 91, 97, 98<br />

inequality, 183, 184<br />

inhibitor, 107, 111, 114<br />

innovation diffusion model, see model<br />

innovation diffusion theory, see model<br />

integer arithmetic, see modular arithmetic<br />

integration<br />

definite integral, 181<br />

Duhamel method, 32<br />

time-step method, 32<br />

inter-story drift, see wall-frame<br />

kinetics<br />

chemical, 107, 108<br />

enzyme, 107–109, 111, 114<br />

Kron reduction, 6<br />

law of excluded middle, see excluded middle<br />

leakage reactance, see reactance<br />

life cycle, see product life cycle<br />

line, 209, 216, 217, 219, 225, 226, 228, 231<br />

skew, 203, 229, 230<br />

line-to-ground fault, see unsymmetrical fault<br />

line-to-line fault, see unsymmetrical fault<br />

linear elastic system, see system<br />

linear equation, see system<br />

linear plot, see plot<br />

linear quadratic regulator, see LQR<br />

linear regression, see regression<br />

Lineweaver-Burk, see equation<br />

load current, see current<br />

logistic growth model, see model<br />

LQR, 54<br />

MAD, see error<br />

mass matrix, see matrix<br />

mathematical induction, see induction<br />

matrix<br />

correlation, 151<br />

covariance, 151<br />

drift, see wall-frame<br />

dynamic, 36<br />

flexibility, 19, 28, 29, 31<br />

mass, 36, 38<br />

positive definite, 151<br />

stiffness, 19, 29, 31, 36

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!