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Almost Linear Time Algorithms for Minsum k-Sink Problems on Dynamic Flow Path Networks [article]

Yuya Higashikawa, Naoki Katoh, Junichi Teruyama, Koji Watase
2020 arXiv   pre-print
We address the facility location problems on dynamic flow path networks.  ...  The problem is to find the location of sinks on a dynamic flow path network in such a way that the aggregate evacuation time (i.e., the sum of evacuation times for all the people) to sinks is minimized  ...  On the other hand, the minsum k-sink problems on dynamic flow networks have not been studied except for the case of path networks [4, 5, 14] .  ... 
arXiv:2010.05729v1 fatcat:tnbo3r6shfcfxjbyshzjkh5rly

Facility location models for distribution system design

Andreas Klose, Andreas Drexl
2005 European Journal of Operational Research  
Predominantly, minsum models embrace location problems of private companies while minmax models focus on location problems arising in the public sector. 3.  ...  This problem, also denoted as multi-source Weber problem (MWP), is NP-hard. It can be modelled as the non-linear mixed-integer program  ...  Usually, they are studied on huband-spoke networks with the following properties: For an undirected graph with node set K a flow exists between every pair i; j 2 K of nodes.  ... 
doi:10.1016/j.ejor.2003.10.031 fatcat:anxksnzagrb3nkwz67uemm673e

Memory Efficient Max Flow for Multi-label Submodular MRFs [article]

Thalaiyasingam Ajanthan, Richard Hartley, Mathieu Salzmann
2017 arXiv   pre-print
Consequently, our algorithm makes it possible to optimally solve multi-label submodular problems involving large numbers of variables and labels on a standard computer.  ...  In this paper, we introduce a variant of the max-flow algorithm that requires much less storage.  ...  We do this by considering one edge (i, j) ∈ E at a time and reconstruct the flow by formulating a small max-flow problem.  ... 
arXiv:1702.05888v1 fatcat:wqym4iknlbc5rfxhfgolknxy2e

Elements of Scheduling [article]

Jan Karel Lenstra, David B. Shmoys
2020 arXiv   pre-print
We continue to receive requests from colleagues who look for a text on the elements of scheduling at an advanced undergraduate or early graduate level.  ...  Gene Lawler was on their committees. It was a natural idea to turn the theses into a textbook on scheduling.  ...  In the first part of the chapter we consider some well-studied algorithmic techniques: namely, linear programming, network flow, and dynamic programming.  ... 
arXiv:2001.06005v1 fatcat:5w7dwzh6nrbb7ateihvrac3734

Summary The Dagstuhl seminar on Combinatorial Approximation Algorithms brought together 54 researchers with affiliations in Austria List of Participants Abstracts Minimizing Service and Operation Costs of Periodic Scheduling Approximating the permanent of a non-negative matrix Dagstuhl-Seminar 9734

Yuval Rabani, David Shmoys, Gerhard Woeginger, Karen Aardal, Yossi Azar, Reuven Bar-Yehuda, Technion Yair Bartal, Berkeley Barvinok, Martin Dyer, David Karger, Howard Karloff, Marek Karpinski (+35 others)
The algorithm uses some properties of "Fibonacci sequences". Using this sequence we present a 1.57-approximation algorithm for the general problem.  ...  Following the example of Paul Erdös, David Williamson offered money rewards for solutions to his open problems; Sanjeev Arora. and Luca Trevisan managed to solve one of his problems (on the Rectilinear  ...  We seek a single source-sink flow path for each commodity so that the demands are satisfied and the total flow routed across any edge is bounded by its capacity.  ... 

Optimization of Markov Random Fields in Computer Vision [article]

Thalaiyasingam Ajanthan, University, The Australian National, University, The Australian National
First, we introduce a memory efficient max-flow algorithm for multi-label submodular MRFs.  ...  Consequently, our algorithm makes it possible to optimally solve multi-label submodular problems involving large numbers of variables and labels on a standard computer.  ...  In fact, the time complexity of one iteration of our algorithm is linear in the number of pixels and labels, which is the first LP minimization algorithm for dense CRFs to have linear time iterations.  ... 
doi:10.25911/5d6c3fc2c15c9 fatcat:nbhkpu7jfrb2bpvuxof6jetm7y

Integrating Workforce Scheduling Aspects into Daily Operations at Trailer Terminals with a Special Focus on Loading and Unloading of Trucks

Giorgi Tadumadze
The planning problem that determines on at which door and in which time interval each truck has to be (un-)loaded is called truck scheduling problem.  ...  More precisely, the considered planning problems are related to trucks' unloading and loading processes at massive transshipment terminals, crucial nodes for many modern transportation networks.  ...  , like total weighted ow time and other minsum objectives.  ... 
doi:10.26083/tuprints-00017583 fatcat:ycyylk4e6jeuzf5rlteqrozow4