Technical Sessions – Monday July 11

3 - A Column Generation Formulation for the Integrated
Aircraft Routing, Crew Pairing, and Tail Assignment
Problem
Sebastian Ruther, University of Newcastle, Australia,
Sebastian.Ruther@uon.edu.au, Natashia Boland, Faramroze
Engineer, Ian Evans
A common problem when integrating airline planning stages is the long planning
horizon of the crew pairing problem. We propose an approach in which
crews initially are only told when they work. This enables us to generate an
overall schedule much closer to the start of the planning horizon. Therefore,
along with a short planning horizon, more detailed and accurate schedules can
be generated. We propose a model based on the Branch-and-Price method
where both the aircraft routing and crew pairing problems are formulated as
subproblems. We present results for small and medium size instances.
4 - Integrated Crew Pairing and Assignment by Column
Generation and Dynamic Constraint Aggregation
Francois Soumis, GERAD, 3000 Cote Ste-Catherine, H3T 2A7,
Montreal, Québec, Canada, francois.soumis@gerad.ca,
Mohammed Saddoune, Issmail Elhallaoui, Guy Desaulniers
The crew scheduling problem is commonly decomposed into two stages which
are solved sequentially. Crew pairing generates a set of pairings covering all
flight legs. Crew assignment generates anonymous blocks covering all pairings.
The simultaneous problem generates a set of blocks covering all flight
legs. It is a large set covering problem highly degenerated. We combine the
column generation and the dynamic constraint aggregation methods to solve it
and save 5% on real-life problems. We will also present the extension to the
personalized case where the blocks of pilots and co-pilots are different but the
pairings need to be the same for robustness.
IFORS 2011 - Melbourne TB-02
Tuesday, 11:00-12:30
� TB-01
Tuesday, 11:00-12:30
Plenary Hall 3
IFORS Survey on OR Practice 2
Stream: OR Practice
Invited session
Chair: John Ranyard, The Management School, Lancaster University,
Department of Management Science, LA1 4YX, Lancaster,
Lancashire, United Kingdom, jranyard@cix.co.uk
1 - OR Practice in the Philippines
Elise del Rosario, ORSP, 14A Cyber One, 11 Eastwood Ave.,
Bagumbayan, 1110, Quezon City, Philippines,
elise@jgdelrosario.com
OR practice has a definite presence in the Philippines but it is not widespread
in the business community, with Internal OR consultants in less than 10 companies.
Size of group, experience and training of analysts, barriers to the use
of OR, OR techniques and software used will be given. Companies without inhouse
OR relegate quantitative analysis to engineering, corporate planning and
management services departments. External consulting firms do not ordinarily
use OR methodologies, whereas academic consultants do. OR applications
cover long-range to operational decisions, in the areas of logistics, facilities,
manpower, service operations planning, risk management and marketing. The
most used tool reported is spreadsheet modelling. The Philippine OR community
is tightly knit and practitioners, from a diversity of industries, are members
of the national OR society, which aims to link academe with practice. Whilst
some OR groups have disbanded, others have formed, and so the size of the OR
community has stayed around the same level.
2 - OR Practice in South Africa
Hans W. Ittmann, CSIR Built Environment, P O Box 395, 0001,
Pretoria, South Africa, hittmann@csir.co.za
IFORS commissioned a survey of OR practice in member countries. A number
of OR practitioners in South Africa also responded. In this talk the results from
the survey will be presented. In addition further background will be given to
the practice and use of OR in the country as well as where the major challenges
lie. The OR society in South Africa organises an annual conference and publishes
it own journal bi-annually. Information from these sources will be used
to supplement the results from the IFORS survey.
3 - OR Practice in Australia and New Zealand
Simon Dunstall, Mathematics, Informatics and Statistics,
CSIRO, Private Bag 33, 3169, South Clayton, Victoria, Australia,
Simon.Dunstall@csiro.au, Baikunth Nath, Andrew J Mason
The survey findings for the two countries will be summarised and key features
of OR practice will be described. Several organisations in both countries have
strong OR teams, some of which have received international acclaim e.g. via
the INFORMS Edelman competition. Some challenges facing the OR practice
communities will be outlined.
� TB-02
Tuesday, 11:00-12:30
Meeting Room 101
Game Theory Applications in Economics I
Stream: Game Theory
Invited session
Chair: Andrea Mantovani, Department of Economics, University of
Bologna, Strada Maggiore 45, 40125, Bologna, Italy,
a.mantovani@unibo.it
1 - The Use of Genetic Algorithm into the Marketing Equilibrium
Analysis
Gülfem Isiklar Alptekin, Computer Engineering, Galatasaray
University, Turkey, gisiklar@gsu.edu.tr
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