buletinul institutului politehnic din iaşi bulletin of the polytechnic ...

B U L E T I N U L I N S T I T U T U L U I P O L I T E H N I C D I N I A Ş I
B U L L E T I N O F T H E P O L Y T E C H N I C I N S T IT U T E O F I A Ş I
Tomul LVIII (LXII), Fasc. 1 2012
MACHINE CONSTRUCTION
C O N T E N T S
Pp.
MIHAI AFRĂSINEI, DORU CĂLĂRAŞU, VASILE DAMASCHIN, IRINA
MARDARE and ADRIAN OLARU, Analysis by Numerical Simulation
of a New Self-Adaptive Hydraulic System Used at Wind Turbines
(English, Romanian summary)................................................................... 1
ADRIAN SORIN AXINTI and GAVRIL AXINTI, Dynamic Models for
Traction Systems (English, Romanian summary)...................................... 9
GAVRIL AXINTI and ADRIAN SORIN AXINTI, Models For The Hydraulic
Seismic Energy Dissipaters (English, Romanian summary)....................... 17
CARMEN BAL, CARMEN IOANA IUHOS and NICOLAIE BAL, Research
on Experimental Heat Effects in a Flow with Harmonic Drive
Installation. (I) Drive Installation of Harmony Flow − Assembly in
Parallel, (English, Romanian summary)..................................................... 23
VLAD BOCĂNEŢ, HORIA ABĂITANCEI, CONSTANTIN CHIRIŢĂ,
MARIUS DENEŞ-POP and LIVIU BĂRNUŢIU, Dynamic Analysis of a
Hydraulic Actuation System of Very Slow Moving Devices
(English, Romanian summary) .................................................................. 29
ILARE BORDEAŞU, MIRCEA POPOVICIU, ADRIAN KARABENCIOV,
ALIN DAN JURCHELA and CONSTANTIN CHIRIŢĂ, New
Contributions in the Correlation of Mechanical Properties with the
Cavitation Resistance of Stainless Steels (English, Romanian summary)...........................................................................................................
35
CONSTANTIN CHIRIŢĂ, ANDREI GRAMA and DUMITRU ZETU,
Research on Frictional Losses in Tensioning Devices at Full Load
(English, Romanian summary)...................................................................
CORNELIU CRISTESCU, PETRIN DRUMEA, CĂTĂLIN DUMITRESCU
and DRAGOŞ ION GUŞĂ, Experimental Research Regarding the
Dynamic Behaviour of Linear Hydraulic Servo-systems (English,
Romanian summary)................................................................................... 51
.FLORINA-CRISTINA FILIP, Effective Methods of Cost Breakdown for
Direct Costs, Tools and Product Costs (English, Romanian
summary)..................................................................................................... 59
43

ANDREI GRAMA, CONSTANTIN CHIRIŢĂ, DUMITRU ZETU and
MIHAI AXINTE, Analysis by Finite Element Method of Assembly
Wedge Grips - Mantle Corbel (English, Romanian summary)................... 65
DANIELA IONESCU, ION BOGDAN and GABRIELA APREOTESEI,
About the Tunable Properties of the YIG Films with Applications in
Microwave Devices Manufacturing (English, Romanian summary) ......... 75
.ALIN LUCA, MIRCEA COZMÎNCĂ and ANA MARIA MATEI,
Experimental Determination of R a and R z on Turning Steels
(English, Romanian summary).................................................................... 85
IRINA MARDARE and IRINA TIŢA, Force Sensor in a WIM Hydrostatic
System (English, Romanian summary)....................................................... 91
ANA-MARIA MATEI, MIRCEA COZMÎNCĂ and ALIN LUCA, Researches
Concerning the Uniformization of Cutting Forces in Face Milling
(English, Romanian summary) .................................................................. 97
MEHRAN DOULAT ABADI (Malaysia) and SHA’RI MOHD YUSOF
(Malaysia), A Preliminary Study of the Key Factors for Sustaining Total
Quality Practices (English, Romanian summary)....................................... 105
MARIUS MILEA and MIRCEA COZMÎNCĂ, Synthesis on the Assessment
of Chips Contraction Coefficient C D (English, Romanian summary) ........ 117
EUGEN-VLAD NĂSTASE and DORU CĂLĂRAȘU, Influence of Chord Variation
on the Performance of a Kinetic Miniturbine (English, Romanian
summary)................................................................................... 121
EUGEN-VLAD NĂSTASE and DORU CĂLĂRAȘU, Theoretical Research
Regarding the Blades Number Influence of the Miniturbine Efficiency
(English, Romanian summary)................................................................... 125
VASILE NĂSUI, About Modelling the Movement Control of the
Electromechanic Linear Actuator (English, Romanian summary)............. 129
IOANA PETRE, TUDOR DEACONESCU, ANDREA DEACONESCU and
DAN PETRE, Finite Element Modeling of a Knee and Hip
Rehabilitation Equipment (English, Romanian summary).......................... 137
IOANA PETRE, TUDOR DEACONESCU, ANDREA DEACONESCU and
DAN PETRE, Some Considerations Regarding Pneumatic Muscle
Volume (English, Romanian summary)...................................................... 143
TEODOR COSTINEL POPESCU and IOAN LEPĂDATU, Modern
Techniques for Experimentation of Adjustable Hydrostatic Pumps
(English, Romanian summary)....................................................................
OCTAVIAN PRUTEANU, CONSTANTIN CĂRĂUŞU and LUCIAN
TĂBĂCARU, Some Considerations about Cold Plastic Deformation of
Bearing Rings (English, Romanian summary) ........................................... 157
149

BRUNO RĂDULESCU and MARA-CRISTINA RĂDULESCU, The Costs
Estimation for the Mechanical Production (English, Romanian
summary)....................................................................................................
LUCIANA-CRISTIANA STAN and VLADIMIR MĂRĂSCU-KLEIN, The
Role of Professional Competence in Business Entrepreneurship (English,
Romanian summary.) .................................................................................
IRINA TIŢA and IRINA MARDARE, Some Aspects Regarding Hydraulic
Systems with Secondary Control (English, Romanian summary)..............
ALEXANDRA TOMA and CORNEL CIUPAN, Man Machine Interface
Ergonomic Design Related to Human Factors (English, Romanian
summary).....................................................................................................
LILIANA TOPLICEANU, ADRIAN GHENADI and MARIUS PASCU,
Study about the Role of Accumulators in Hydraulic Secondary Control
Systems (English, Romanian summary)....................................................
CĂTĂLIN UNGUREANU, IRINA COZMÎNCĂ and RADU IBĂNESCU,
Considerations about Control Charts Used in Statistical Process Control.
(II) Control Charts for Infrequent and Cumulative Data (English,
Romanian summary) ..................................................................................
DĂNUŢ ZAHARIEA, Functional Diagrams for Modeling the Reservoir
Emptying Process through a Small Emptying Orifice (English,
Romanian summary)...................................................................................
DĂNUŢ ZAHARIEA, Functional Diagrams for Modeling the Reservoir
Emptying Process through an Emptying Pipe (English,
Romanian summary)...................................................................................
DAN POPESCU, A Pleading for the Modernization of Machine Tools in
National Industry (English, Romanian summary)......................................
169
177
185
191
197
203
211
219
227
ANALYSIS BY NUMERICAL SIMULATION OF A NEW SELF-
ADAPTIVE HYDRAULIC SYSTEM USED AT WIND TURBINES
by
MIHAI AFRĂSINEI, DORU CĂLĂRAŞU, VASILE DAMASCHIN,
IRINA MARDARE and ADRIAN OLARU
Abstract. The paper presents the methodology and the results
from the analysis by numerical simulation of a self adaptive
hydraulic transmission in closed circuit for low power wind
turbines. In order to analyze the simulation model, realized using
Simulink, the pump drive speed was considered as input value.

Based on the resulted unit step responses, the system has a good
working behaviour, stable dynamically to the wind speed variation
and also to the load variations at the motor shaft.
Key words: hydraulic transmission, wind turbine, Simulink,
unit steps.
DYNAMIC MODELS FOR TRACTION SYSTEMS
by
ADRIAN SORIN AXINTI and GAVRIL AXINTI
Abstract. The work presents a classification of traction
systems as a function of structure, the systems being classified
into: integrally mechanic-traction systems–STIM, mechanichydrostatical
traction -STMH and integrally traction hydrostatical
systems STIH. Each structural model contains the main
components from dynamic point of view: the heat engine as the
source of energy, the transmission of the traction and the system
for movement formed of wheels with tyres or of self-propelled
equipment. For each structural model is the dynamic model to
which dynamic analyses should be done by excitation
accomplished by the road (the runaway). The necessity of these
models has been due to the study models of dynamic behavior and
of traction systems comparison of different structures, mechanic,
mechanic and hydraulic.
Key words: dynamic model, transmission, traction, hydraulic.
MODELS FOR THE HYDRAULIC SEISMIC ENERGY
DISSIPATERS
by
GAVRIL AXINTI and ADRIAN SORIN AXINTI
Abstract. This article refers to the complex seismic energy
dissipaters based on hydrostatic equipments that are capable of
destroying the energy of the earthquake, shock or vibration, for
various frequencies, dissipaters that connect the body system object
to the dynamic phenomenon with its ground basis.
Key words: models, hydraulic, seismic energy, dissipater, etc.

RESEARCH ON EXPERIMENTAL HEAT EFFECTS IN A FLOW
WITH HARMONIC DRIVE INSTALLATION
I. DRIVE INSTALLATION OF HARMONY FLOW − ASSEMBLY
IN PARALLEL
by
CARMEN BAL, CARMEN IOANA IUHOS and NICOLAIE BAL
Abstract. Paper aims to highlight the phenomenon of heat
conducted into a sonic installation. Heat is produced and sent away
by vibration.
Key words: sonic pressure, sonic flow, friction resistance, sonic
condenser, temperature.
DYNAMIC ANALYSIS OF A HYDRAULIC ACTUATION
SYSTEM OF VERY SLOW MOVING DEVICES
VLAD BOCĂNEŢ, HORIA ABĂITANCEI, CONSTANTIN
CHIRIŢĂ,
MARIUS DENEŞ-POP and LIVIU BĂRNUŢIU
Abstract. The paper presents research conducted for a hydraulic
actuation system designed to propel a slow moving device. During
system run, the stability of the system has to be assured, considering
the slow moving velocity of the device. In order to analyse the
system, a multi-domain model was developed to identify the
influences of geometry and running conditions on system behaviour.
In order to appreciate the influences of different running parameters,
the propelling speed, pump displacement and motor displacement
are considered. Instabilities at system run-up are identified and are
relative rapidly damped.
Key words: fluid power, slow moving system, multi-domain
simulation etc.
NEW CONTRIBUTIONS IN THE CORRELATION OF
MECHANICAL PROPERTIES WITH THE CAVITATION
RESISTANCE OF STAINLESS STEELS

y
ILARE BORDEAŞU MIRCEA POPOVICIU, ADRIAN
KARABENCIOV,
ALIN DAN JURCHELA and CONSTANTIN CHIRIŢĂ
Abstract. The paper analyzes the cavitation resistance of
twelve stainless steels based on the correlations between the main
mechanical properties (hardness, tensile strength and flow limit)
with the 1/MDPR parameter. Data regarding the microstructure is
presented. The microstructure is important for the analysis of
cavitation damage. Diagrams presented in the paper also offer the
ranking of the studied steels in terms of cavitation resistance, using
the steels’ mechanical properties as landmark. Final conclusions
show that steels with different values of the mechanical properties
and different microstructures can have similar cavitaton resistances,
thus helping hydromechanical equipment manufacturers in the
selection of steels according to the hydrodynamic intensities of the
cavitation conditions.
Key words: cavitation erosion, mechanical properties,
microstructure, cavitation resistance.
RESEARCH ON FRICTIONAL LOSSES INTENSIONING
DEVICES AT FULL LOAD
by
CONSTANTIN CHIRIŢĂ, ANDREI GRAMA and DUMITRU ZETU
Abstract. In this paper determination of size of frictional
losses at full load friction tensioning devices is performed using
theoretical calculations of loading force and is compared with
measured pulling force developed by tensioning device. It was
tested a device used for reinforcement tensioning, device designed
and realized in Hydraulic and Pneumatic Systems Engineering
Department, Faculty of Mechanical Engineering and Industrial
Management, Technical University "Gheorghe Asachi" Iasi. The
aim of this research is to compare values obtained with the values
given in literature for tensioning devices made by profile
companies of the world.
Key words: pre-tensioning, device for tensioning, frictional
force, tendon.

EXPERIMENTAL RESEARCH REGARDING THE DYNAMIC
BEHAVIOR OF LINEAR HYDRAULIC SERVO-SYSTEMS
by
CORNELIU CRISTESCU, PETRIN DRUMEA,
CĂTĂLIN DUMITRESCU and DRAGOŞ ION GUŞĂ
Abstract. The paper presents the results of experimental
research on the dynamic behavior of linear hydraulic motors and
linear positioning servo-systems carried out in INOE 2000-IHP, in
the framework of the NUCLEU Program. The experimental
investigations were conducted on an experimental stand with data
acquisition and computer processing. The article presents some
experimental graphic results obtained in the research, results that
are of real scientific interest, which have a practical value through
the using of them in the design activities of the fluid power
components and equipments.
Key words: linear hydraulic servo-systems, dynamic
behavior, experimental research, test stand, data acquisition.
EFFECTIVE METHODS OF COST BREAKDOWN
FOR DIRECT COSTS, TOOLS AND PRODUCT COSTS
by
FLORINA-CRISTINA FILIP
Abstract. Various customers require a detailed breakdown of
the product costs in the quotation and delivery phase, depending on
the project costs involved. Some customers have different
procedures and consequently use their own forms. In principle,
detailed product cost illustrations for customers are subject to
restrictions and may only be forwarded to customers once this has
been agreed with the relevant departments. The content of the
product cost breakdown is defined in the escalation stages and
forwarded on. All the basic information for all stages about tooling
adjustment costs (testing costs), tooling costs, design costs and typespecific
measuring equipment costs is the same. The aim of this
procedure is to ensure that the information presented to the customer
is of uniform content. This is particularly important if the customer
submits an enquiry for a product to different sales regions on an
uncoordinated basis. The purpose of this paper is to regulate the

handling and content of detailed product cost illustrations based on
the cost value (standard quotation cost value) for customers.
Through the use of standard forms, detailed product costs are only
passed on to the customer on a restricted basis. Product cost data
may only be handed over to the customer when all other
possibilities have been rejected and it is unavoidable.
Key words: administration cost, standard, price, quality, profit.
ANALYSIS BY FINITE ELEMENT METHOD OF ASSEMBLY
WEDGE GRIPS - MANTLE CORBEL
by
ANDREI GRAMA, CONSTANTIN CHIRIŢĂ,
DUMITRU ZETU and MIHAI AXINTE
Abstract. To achieve the required pulling and tensioning
tendons in prestressed concrete structures it uses locking systems.
Locking systems must be made of materials with appropriate
strength so as not to destroy their active surface due the pulling
forces having large and very large values. This is achieved by using
alloy steel, heat treated on active surfaces and by dimensioning so
as to provide necessary forces and unlocking of wedge grips at the
end of tension cycle.
Key words: wedge grips, clamping device, tensioning device,
pretensioning, finite elements analysis, virtual model.
ABOUT THE TUNABLE PROPERTIES OF THE YIG FILMS
WITH APPLICATIONS IN MICROWAVE DEVICES
MANUFACTURING
by
DANIELA IONESCU, ION BOGDAN and GABRIELA APREOTESEI
Abstract. The tunable properties of the yttrium iron garnet
(YIG) films with applications at microwave devices were
investigated in this paper. For improving the manufactured
systems, two directions are to be followed in research regarding the
YIG special properties: the frequency tuning capabilities and the
tunable negative permeability of the YIG structures. Study was
performed by structural simulation methods with HFSS 13.0 by

Ansoft. A dc applied magnetic field (3 ÷ 6.5 kOe) was set in order
to obtain the ferromagnetic resonance modification of the material.
By simulations, tunability was achieved in the 12 - 20 GHz
frequency range. The tunable electromagnetic properties of the
YIG films were also studied in ac electromagnetic fields (12 - 30
GHz), on the high-frequency side of the resonance. The fielddriven
response of the labyrinthine magnetic domain walls is
harmonic, determining a similar evolution of the magnetization.
For a manufactured metamaterial including the YIG film and a
metallic grid array, simulated with HFSS, the negative magnetic
permeability was determined in a controlled frequency domain.
This domain was identified as 13 - 20 GHz, depending on the
metamaterial structure and controlled by the dc/ac driving field.
The study is dedicated to the performance optimization of the YIG
devices in microwave range.
Key words: advanced modeling techniques, simulation in
manufacturing systems, optimal design.
EXPERIMENTAL DETERMINATION OF
R a AND R z ON TURNING STEELS
by
ALIN LUCA, MIRCEA COZMÎNCĂ and ANA MARIA MATEI
Abstract. Establishing the roughness of cutting parts is very
important because it affects the functioning of the work pieces. This
influence reflects the operating characteristics of the piece such as
wear resistance, corrosion, the coefficient of friction, the degree of
tightness, etc. Surface roughness is characterized by different
roughness parameters and the most important are the arithmetic
average deviation of the profile R a and ten-point mean roughness
R z . This paper aims to highlight the relationship between R a and R z
by measuring the roughness of specimens subjected to the turning
process.
Key words: cutting, roughness, roughness parameters.
FORCE SENSOR IN A WIM HYDROSTATIC SYSTEM
by

IRINA MARDARE and IRINA TIŢA
Abstract. Weigh-in-motion of road vehicles is essential for the
management of freight traffic road infrastructure and maintenance.
Various types of weigh in motion sensors have been developed.
Existing WIM systems still have limited accuracy and/or
excessively high cost, and their durability in many circumstances
was not proven. We propose a hydraulic system with a force sensor.
It is simple, robust and relatively cheap. In this paper is presented
such a system. On these bases it was developed an experimental
setup and in the same time the SimHydraulics model so one can use
only the simulation in the design process in order to obtain
maximum efficiency.
Key words: hydraulic system, force sensor, weigh-in-motion,
pressure measurement.
RESEARCHES CONCERNING THE UNIFORMIZATION
OF CUTTING FORCES IN FACE MILLING
by
ANA-MARIA MATEI, MIRCEACOZMÎNCĂ and ALIN LUCA
Abstract. This paper presents some theoretical results
regarding the evaluation of cutting force’s components in face
milling. Face milling force depends on the every variant of face
milling process (number of teeth which simultaneously cut) and the
relative position between cutting teeth and the material being cut
(cut-down milling and cut-up milling). Regarding to this,
determination of the cutting force components in face milling, F Z ,
F X , F Y , is based on the forces for a single tooth, the cutting tooth
position beside the XYZ coordinates system of the tool and the
number of teeth that simultaneously cut. In order to standardize the
relationships, a calculus of some practical situations is proposed.
Key words: cutting, face milling, forces, constants.
A PRELIMINARY STUDY OF THE KEY FACTORS FOR
SUSTAINING TOTAL QUALITY PR ACTICES
by
MEHRAN DOULAT ABADI and SHA’RI MOHD YUSOF

Abstract. Quality management is broadly recognized around the
world as a very important competitive priority for the long-term
success of an organization. Over the last decades, a numerous
quality management concepts have been applied and been practiced
by various organizations to attain world-class statue. However, the
recognition of the successes through using the quality management
approach historically has been made by obtain national quality or
business excellence awards. Achieving excellence is hard enough at
the best of times; sustaining it is even harder. Organizations face
many challenges and impediments in sustaining a quality excellence
framework in the long run to drive business improvement. This
paper will attempt to investigate and identify the key factors
affecting the implementation of quality award model through
literature review and thus to list these factors. Hence, understanding
of the factors will help the organizations to ensure that these are
dealt with appropriately in their journey towards excellence.
Key words: Total quality management, sustainability, business
excellence, success factors.
SYNTHESIS ON THE ASSESSMENT OF
CHIPS CONTRACTION COEFFICIENT C D
by
MARIUS MILEA and MIRCEA COZMÎNCĂ
Abstract. The assessment of plastic deformation of chips can
be done based on theoretical and experimental considerations. This
paper presents the two ways of assessing the chips contraction
coefficient, namely the theoretical and experimental methods. The
results obtained from both methods will be used to develop a
mathematical model for chips contraction coefficient.
Key words: chips contraction coefficient, theoretical methods,
experimental methods.
INFLUENCE OF CHORD VARIATION ON THE
PERFORMANCE
OF A KINETIC MINITURBINE
by
EUGEN-VLAD NĂSTASE and DORU CĂLĂRAŞU

Abstract. In this paper we present an analysis of miniturbine
performance when the value of chord is variable. This study is
conducted for a given situation in which is known the average flow
speed and number and the geometry of blades for a kinetic
miniturbine.
Key words: water current turbines, kinetic miniturbine.
THEORETICAL RESEARCH REGARDING THE BLADES
NUMBER INFLUENCE OF THE MINITURBINE EFFICIENCY
by
EUGEN-VLAD NĂSTASE and DORU CĂLĂRAŞU
Abstract. The aim of the paper is to achieve a theoretical study
on the influence of the number of blades on the performance of
miniturbine. The study is conducted to a location with average
speed of water flow known.
Key words: renewable energy, kinetic turbine, energy
conversion.
ABOUT MODELLING THE MOVEMENT CONTROL
OF THE ELECTROMECHANIC LINEAR ACTUATOR
by
VASILE NĂSUI
Abstract. This article refers to the conception and the
practical achievement of some systems of linear movement of
electro-mechanical actuator type used to position precisely of some
pre-working equipment. These systems have to own dynamic
characteristic high precision and high viability. The important
functions of the actuator is the movement control achieved by an
appropriate electronic. The electro-mechanic acting can be
developed by using appropriate control destinations such as the
loading equipment the actuators have to fulfill strict and stable
criteria in any situation. The actuators have multiple applications
both industrial and of these products.
Key words: fuzzy logistic, linear actuator, controller,
advanced control.

FINITE ELEMENT MODELING OF A KNEE AND
HIP REHABILITATION EQUIPMENT
by
IOANA PETRE, TUDOR DEACONESCU, ANDREA DEACONESCU
and DAN PETRE
Abstract. In this paper it is presented the finite element
modeling of rehabilitation equipment for the knee and hip
affections using CATIA V5R19 Software. It is presented the
equipment to be analyzed, the material, type of analysis, the
constraints and the loads applied. After analyze is made, the soft
shows the results, which are interpreted. The results of the analysis,
Von Missed stresses and displacements show the resistance of the
equipment under loadings conditions.
Key words: rehabilitation equipment, Finite Element
Modeling, CATIA.
SOME CONSIDERATIONS REGARDING PNEUMATIC
MUSCLE VOLUME
by
IOANA PETRE, TUDOR DEACONESCU, ANDREA DEACONESCU
and DAN PETRE
Abstract. A pneumatic artificial muscle is composed of an
inner tube of variable length, made of a flexible material, typically
neoprene. The tube is covered with a multilayer texture, made of
nylon with strengthening and protecting role from the environment
influences. Under the action of compressed air it increases its
diameter and decreases its lengths. A pneumatic muscle is used
successfully in different areas, especially in robotics. The paper
presents some calculus models for volume of the pneumatic
muscle, considered in relaxed and contracted state.
Key words: pneumatic muscle, volume, relaxed state,
contracted state.
MODERN TECHNIQUES FOR EXPERIMENTATION
OF ADJUSTABLE HYDROSTATIC PUMPS

y
TEODOR COSTINEL POPESCU and IOAN LEPĂDATU
Abstract. This paper aims at dissemination of experimental
research work conducted at IHP Bucharest, in order to determine the
actual performance of hydrostatic adjustable pumps. To this end
laboratory tests were conducted on a radial piston pump MOOG
type, which can automatically vary the flow rate by adjusting the
eccentricity of the stator ring. The paper presents the experimental
modern means used for this purpose, the type of experimental tests,
results and their interpretation.
Key words: hydrostatic adjustable pump, experimental tests.
SOME CONSIDERATIONS ABOUT COLD PLASTIC
DEFORMATION OF BEARING RINGS
by
OCTAVIAN PRUTEANU, CONSTANTIN CĂRĂUŞU and LUCIAN
TĂBĂCARU
Abstract. The equipment used to conduct experimental
research enables the user to change the deformation force, the
deformation feed, as well as the speed of the half-finish feeding
roller. Paper describes the results obtained on the roughness, out-ofroundness
and microhardness of the exterior and interior ring races
of bearing 6210, further to changes in the three work parameters.
The values detected were recorded in tables and presented by
graphical representations, and they substantiate our conclusions
related to the best work parameter ranges, where the quality
parameter deviations are minimal. The paper also shows the
mathematical processing of the microhardness results recorded for
the ring race surfaces.
Key words: plastic deformation, force, feed, speed, roughness,
out-of-roundness, circularity, microhardness
THE COSTS ESTIMATION FOR THE MECHANICAL
PRODUCTION
by
BRUNO RĂDULESCU and MARA-CRISTINA RĂDULESCU

Abstract. This paper presents the decomposition and the
definition of a technical cost that include supplier cost,
subcontracting cost and production cost.
Key words: production programme, cost, project budget.
THE ROLE OF PROFESSIONAL COMPETENCE
IN BUSINESS ENTREPRENEURSHIP
BY
LUCIANA-CRISTIANA STAN and VLADIMIR MĂRĂSCU-KLEIN
Abstract: In a market economy based on competition and risk,
business sector development is a priority. For the Romanian
economy, business sector development, especially skills are an
important part of economic restructuring policy, which positively
influence the pace of sustainable economic growth. By their
characteristics: innovation, close ties with the community, high
dynamic, optimal exploitation of local resources, creating jobs,
developing small and medium impact, especially at lower levels,
namely the local and regional levels. Entrepreneurship skills are
reflected in fact the result of ideas and projects that illustrate the
determination and attitude of the entrepreneur to identify and use
opportunities that arise at a time. The motivation to create a new
business is a prerequisite for the emergence of entrepreneurial
initiative and receptiveness to a product or service is what brings
success.
Key words: responsible entrepreneurship, professional
competence, questionnaires, sample.
SOME ASPECTS REGARDING HYDRAULIC SYSTEMS
WITH SECONDARY CONTROL
by
IRINA TIŢA and IRINA MARDARE
Abstract. The high costs for energy and the increased necessary
of it lead to hydraulic systems working at a certain power with an
optimum efficiency and consequently minimum energy
consumption. The calculus of such systems is focused on the energy

price and not on investment only. The hydraulic systems with
secondary control are not only saving energy but also recovering it.
In the paper two cases of such systems are presented. One can see
the Simscape diagram for one of them and the simulation results for
both.
Key words: hydraulic system, secondary control, numeric
simulation.
MAN MACHINE INTERFACE ERGONOMIC DESIGN
RELATED TO HUMAN FACTORS
by
ALEXANDRA TOMA and CORNEL CIUPAN
Abstract. When a human-machine-interface gets less priority
in a design analysis, unnecessary hazards may be imposed.
Ergonomic and human factors should be incorporated as a part of
this process, so they can show the importance of human machine
interaction. The objective of this paper is to highlight these factors
that are able to provide a platform where this emerging technology
part interaction can increase productivity, quality, satisfaction,
safety and health in a workplace. The article contribution is a
theoretical one taking into consideration helpful ideas in a human
machine interface ergonomic design.
Key words: design, ergonomics, human factors, humanmachine-interface.
STUDY ABOUT THE ROLE OF ACCUMULATORS IN
HYDRAULIC SECONDARY CONTROL SYSTEMS
by
LILIANA TOPLICEANU, ADRIAN GHENADI and MARIUS PASCU
Abstract. The paper is focused on the functional role of
accumulators in hydraulic secondary control systems.
Mathematical models are presented and the same the simulation
results for a gas-charged accumulator using SimHydraulics tool
from programming language Matlab.
Key words: accumulator, secondary control system.

CONSIDERATIONS ABOUT CONTROL CHARTS
USED IN STATISTICAL PROCESS CONTROL
II. CONTROL CHARTS FOR INFREQUENT AND
CUMULATIVE DATA
by
CĂTĂLIN UNGUREANU, IRINA COZMÎNCĂ and RADU
IBĂNESCU
Abstract. Processes quality control is very important for
organizational success and maintaining it on market. SPC is a
reliable and economical method of monitoring the evolution of a
productive process. In industrial practice are encountered cases
when classical control charts, Shewhart type, are not recommended.
The purpose of this paper is to analyze control charts using in these
cases. Special attention is given to the EWMA and CUSUM charts.
Key words: quality control, control chart, EWMA chart,
CUSUM chart.
FUNCTIONAL DIAGRAMS FOR MODELING
THE RESERVOIR EMPTYING PROCESS
THROUGH A SMALL EMPTYING ORIFICE
by
DĂNUŢ ZAHARIEA
Abstract. In this paper the emptying process of a reservoir with
constant cross-sectional area through an emptying small orifice will
be investigated. Two types of reservoir will be considered: with
constant head and with variable head. The pressure at the water
surface and also the velocity of this surface, as well as the flow
discharge coefficient of the emptying orifice will be considered. The
fundamental equations governing the reservoir emptying process
will be presented (the analytical method). For modeling and
simulating the reservoir emptying process two functional diagrams
based on MATLAB/Simscape computational approach suited to
analyze the real physical systems consisting of real physical
functional blocks will be presented (the functional diagrams

method). The functional diagrams allow obtaining the graphical
representation of the level of the liquid from the reservoir during the
time of the emptying process but also the graphical representation of
the flow rate of the liquid through the orifice. Using the measured
values of flow rate, the velocity and the Reynolds number can be
calculated. A comparative analysis of the numerical results for the
emptying time for constant head and for variable head reservoirs,
obtained with the analytical and the functional diagram methods
will be presented.
Key words: constant cross-sectional area reservoir, emptying
time, emptying orifice, functional diagram, MATLAB.
FUNCTIONAL DIAGRAMS FOR MODELING THE RESERVOIR
EMPTYING PROCESS THROUGH AN EMPTYING PIPE
by
DĂNUŢ ZAHARIEA
Abstract. In this paper the emptying process of constant head
and variable head reservoirs with constant cross-sectional area
through an emptying pipe will be investigated. The pressure at the
water surface and also the velocity of this surface, as well as the
head loss due to friction along the emptying pipe will be considered.
Two methods will be presented: the analytical method based on the
fundamental equations governing the reservoir emptying process
and the functional diagrams method based on MATLAB/Simscape
computational approach suited to analyze the real physical systems.
A comparative analysis of the numerical results for the emptying
time for constant head and for variable head reservoirs, obtained
with the analytical and the functional diagram methods will be
presented.
Key words: constant cross-sectional area reservoir, emptying
time, emptying pipe, functional diagram, MATLAB.
A PLEADING FOR THE MODERNIZATION OF
MACHINE TOOLS IN NATIONAL INDUSTRY
by
DAN POPESCU

Abstract. Numerical controls have a great role in increasing the
efficiency of the electric drive of the machine tool, thus in the
energy saving. Measurements were done for two of those (one
equipped with numerical control and a converter for the
asynchronous motor of the main drive, and another with no
numerical control and with a converter for the d.c. motors of the
main drive). Measurements were done using a kit which was
specialized in acquiring and handling energetic data. This project
presents the diagrams resulted from the measurements in a
comparative study. The monitored parameters were the following:
actual values of voltage and currents during the three phases, the
content of harmonics, or the frequency spectrum for all three phases,
the frequency of the feeding voltage, active and reactive power,
energy, and the power factor.
Key words: numerical controls, active and reactive power,
energy, converter.