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Path Planning for Groups Using Column Generation [chapter]

Marjan van den Akker, Roland Geraerts, Han Hoogeveen, Corien Prins
2010 Lecture Notes in Computer Science  
In current games, these problems are solved by using greedy ad hoc rules, leading to long traversal times or congestions and deadlocks near narrow passages.  ...  If there is only one group, then it can be solved efficiently as a dynamic flow problem. If there are several groups with different origins and destinations, then the problem becomes N P-hard.  ...  Path Planning for Multiple Groups In this section, we consider the path planning problem for multiple groups of units.  ... 
doi:10.1007/978-3-642-16958-8_10 fatcat:y3yknefmk5bz5ba2rvfy54mbly

A Decision Support System for Crew Planning in Passenger Transportation Using a Flexible Branch-and-Price Algorithm

Richard Freling, Ramon M. Lentink, Albert P.M. Wagelmans
2004 Annals of Operations Research  
This paper discusses a decision support system for airline and railway crew planning. The system is a state-of-the-art branch-and-price solver that is used for crew scheduling and crew rostering.  ...  Crew scheduling is crew planning for one or a few days that results in crew duties or pairings, and crew rostering is crew planning for at least one week for individual crew members.  ...  Acknowledgements The authors like to thank Daan Ament from ORTEC Consultants for his valuable comments. References Andersson, E., Housos, E., Kohl, N., Wedelin, D., 1998  ... 
doi:10.1023/b:anor.0000019090.39650.32 fatcat:rypjcuiq5vcq7ngmrvxsfzbogm

Space-Time Group Motion Planning [chapter]

Ioannis Karamouzas, Roland Geraerts, A. Frank van der Stappen
2013 Springer Tracts in Advanced Robotics  
We present a novel approach for planning and directing heterogeneous groups of virtual agents based on techniques from linear programming.  ...  The computed space-time plan is combined with an agent-based steering method to handle collisions and generate the final motions of the agents.  ...  Algorithm 1 Column Generation 1: Find initial paths and add them as columns to the LP 2: repeat 3: Solve LP-relaxation 4: for each group C i do 5: Find a shortest (s i (0) − t i (τ))-path in G T w.r.t.  ... 
doi:10.1007/978-3-642-36279-8_14 fatcat:tarh3cjll5es3iztocamkub7o4

Dependable cardinality forecasts for XQuery

Jens Teubner, Torsten Grust, Sebastian Maneth, Sherif Sakr
2008 Proceedings of the VLDB Endowment  
A variant of projection paths [15] provides a versatile interface into which existing techniques for XPath cardinality estimation can be plugged in seamlessly.  ...  to yield dependable forecasts for arbitrary XQuery (sub)expressions.  ...  Assuming equi-sized groups, the average group size is |q| / γ . Since produces numbers between 1 and the group size, this is also the domain size we estimate for the new column a.  ... 
doi:10.14778/1453856.1453908 fatcat:mdb7iqpozvgvtn6lcqdlbt6xwe

Airline crew scheduling from planning to operations

Claude P. Medard, Nidhi Sawhney
2007 European Journal of Operational Research  
We describe how pairing construction and pairing assignment are done in a single step, and provide solution techniques based on simple tree search and more sophisticated column generation and shortest-path  ...  At the operational level, the (re) planning period is considerably smaller than during the strategic planning phase.  ...  Our special thanks go to Curt Hjorring and Lennart Bengtsson for their support and advice about the pairing reduced cost column generator.  ... 
doi:10.1016/j.ejor.2005.12.046 fatcat:tzlstpnm4rbsdgy2xn5ljsojhi

Average Case Constant Factor Time and Distance Optimal Multi-Robot Path Planning in Well-Connected Environments [article]

Jingjin Yu
2019 arXiv   pre-print
Fast algorithms for optimal multi-robot path planning are sought after in real-world applications.  ...  In this work, we develop a first low-polynomial running time algorithm, called SplitAngGroup (SaG), that solves the multi-robot path planning problem on grids and grid-like environments, and produces constant  ...  In [13] , individual paths are planned first. Then, interacting paths are grouped together for which collision-free paths are scheduled using Operator Decomposition (OD).  ... 
arXiv:1706.07255v4 fatcat:a4mr65yhw5e5zi5ohcubfkezby

A Path-Generation Matheuristic for Large Scale Evacuation Planning [chapter]

Victor Pillac, Pascal Van Hentenryck, Caroline Even
2014 Lecture Notes in Computer Science  
In contrast with the column generation technique, the proposed approach does not rely on the explicit pricing of new columns but instead exploits features of the incumbent solution to generate one or more  ...  columns in the master problem.  ...  The algorithm can be used for strategic and tactical planning.  ... 
doi:10.1007/978-3-319-07644-7_6 fatcat:y2rift6bifg5hona3fvtezroxe

Caching all plans with just one optimizer call

Debabrata Dash, Ioannis Alagiannis, Cristina Maier, Anastasia Ailamaki
2010 2010 IEEE 26th International Conference on Data Engineering Workshops (ICDEW 2010)  
For this purpose, commercial DBMS feature automated physical designers suggesting an efficient DB design by using the optimizer as a cost model.  ...  Recently techniques cache the optimizer's output and evaluate some plans with the cached results, reducing the number of calls to the optimizer.  ...  The Grouping Planner isolates the grouping and ordering columns. It also identifies the interesting orders for the query.  ... 
doi:10.1109/icdew.2010.5452737 dblp:conf/icde/DashAMA10 fatcat:rwhl4ieagfhu5oz4jjxf5emnni

Phase space navigator: Towards automating control synthesis in phase spaces for nonlinear control systems

Feng Zhao
1991 IFAC Proceedings Volumes  
We have demonstrated the strategy with a program that automatically synthesizes r 0t , 2 o global control paths for stabilizing a steel column buckling under compression.  ...  The local trajectory generator uses the flow information about the phase space trajectories to produce ] smoothed trajectories.  ...  on Mathematics and Computation for developing the MIT Scheme programming language and-utilities.  ... 
doi:10.1016/b978-0-08-041698-4.50020-2 fatcat:4p7vntd6urgvnouqpdgmwq2bza

Phase space navigator: Towards automating control synthesis in phase spaces for nonlinear control systems

Feng Zhao
1991 Annual Review in Automatic Programming  
We have demonstrated the strategy with a program that automatically synthesizes r 0t , 2 o global control paths for stabilizing a steel column buckling under compression.  ...  The local trajectory generator uses the flow information about the phase space trajectories to produce ] smoothed trajectories.  ...  on Mathematics and Computation for developing the MIT Scheme programming language and-utilities.  ... 
doi:10.1016/0066-4138(91)90016-5 fatcat:jlayj442ibfa3c3j7rx7yudx6i

Planning the flight routes of the unmanned aerial vehicle by solving the travelling salesman problem

Vladimir Vorotnikov, Igor Gumenyuk, Pavel Pozdniakov
2017 Tehnologìčnij Audit ta Rezervi Virobnictva  
plannIng the flIght routes of the unmanned aerIal VehICle By solVIng the traVellIng salesman proBlem Розглянуто методи розв'язання задачі комівояжера для планування маршрутів польоту безпілотних літальних  ...  The effectiveness of the methods of solving the traveling salesman problem (Monte Carlo, reduction of rows and columns, averaged coefficients) is analyzed for planning the UAV flight paths using software  ...  In future studies, it is planned to use this method for the UAV group, taking into account the breakdown of the wireless network into clusters to ensure the connectivity of mobile subscribers.  ... 
doi:10.15587/2312-8372.2017.108537 fatcat:gbc64vnju5gpzhsakq2wl2feg4

A Conflict-Based Path-Generation Heuristic for Evacuation Planning [article]

Victor Pillac and Pascal Van Henetenryck and Caroline Even
2013 arXiv   pre-print
This paper proposes a conflict-based path-generation approach for evacuation planning.  ...  Each new path is generated to remedy conflicts in the evacuation and adds new columns and a new row in the master problem.  ...  We use a conflict-based path generation which relies on problem-specific knowledge to generate new columns that will potentially improve the objective function of the master problem.  ... 
arXiv:1309.2693v1 fatcat:7hkljtlclzdazcu2kxcvswgrlm

Enrollee mix, treatment intensity, and cost in competing indemnity and HMO plans

Daniel Altman, David Cutler, Richard Zeckhauser
2003 Journal of Health Economics  
We decompose cost differences for eight major medical conditions into four sources: demographics, incidence within demographic groups, treatment intensity, and prices per service.  ...  Greater incidence of disease in the indemnity plan (both from demographics themselves and within demographic groups) and higher prices each explain nearly 50% of the difference.  ...  Sloan Foundation for financial support. The data used in this paper are proprietary.  ... 
doi:10.1016/s0167-6296(02)00094-2 pmid:12564716 fatcat:2okfztnhpfespklbqkmalgodxe

Optimizing Restoration Capacity in the AT&T Network

Ken Ambs, Sebastian Cwilich, Mei Deng, David J. Houck, David F. Lynch, Dicky Yan
2000 Interfaces  
The approach centers on a linear programming model to minimize the cost of the restoration network and uses column generation to generate new restoration paths as needed.  ...  This tool was then extended to plan for the recovery of a switching-center disaster and to reoptimize the entire restoration network.  ...  Acknowledgments We thank Clayton Lockhart, Percy Tarapore, and Luis Vitoria for their contin-  ... 
doi:10.1287/inte.30.1.26.11621 fatcat:lohmeuwcyzgk3psygenxmfv3mu

Implementing a scalable XML publish/subscribe system using relational database systems

Feng Tian, Berthold Reinwald, Hamid Pirahesh, Tobias Mayr, Jussi Myllymaki
2004 Proceedings of the 2004 ACM SIGMOD international conference on Management of data - SIGMOD '04  
In this paper, we propose an implementation that uses a relational database as the matching engine.  ...  Earlier solutions to this problem usually built large finite state automata for all the XPath subscriptions in memory.  ...  ACKNOWLEDGEMENTS The authors would like to thank Marc Schunk for designing the test case for the simple flat XML data. David J.  ... 
doi:10.1145/1007568.1007623 dblp:conf/sigmod/TianDPRMM04 fatcat:sb25p6jmfvc4vnsbkskmrhy7pu
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