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The Maximum Flow Problem for Oriented Flows

Stanley Schade, Martin Strehler, Marc Herbstritt
2016 Algorithmic Approaches for Transportation Modeling, Optimization, and Systems  
In several applications of network flows, additional constraints have to be considered. In this paper, we study flows, where the flow particles have an orientation.  ...  If the end position has a mandatory orientation, not every path from source to sink is feasible for routing or additional transposition maneuvers have to be made.  ...  AT M O S 2 0 1 6 7:6 The Maximum Flow Problem for Oriented Flows The notion of an expanded graph enables us to formulate the maximum flow problem with orientations as a linear optimization problem.  ... 
doi:10.4230/oasics.atmos.2016.7 dblp:conf/atmos/SchadeS16 fatcat:nu4hduc3nbg57eskbvvkyicq2i

Graph Orientation and Flows Over Time [article]

Ashwin Arulselvan, Martin Groß, Martin Skutella
2014 arXiv   pre-print
We present more results of similar flavor and also show non-approximability results for finding the best orientation for single and multicommodity maximum flows over time.  ...  Thus the question arises, what influence the orientation of the network has on the network flow over time problem that is being solved on the oriented network.  ...  We thank the anonymous reviewers for their helpful comments.  ... 
arXiv:1409.3081v3 fatcat:r66y3etay5ha7heih7ihrdwgta

Dynamic Contraflow with Orientation Dependent Transit Times Allowing Intermediate Storage

Durga Prasad Khanal, Urmila Pyakurel, Stephan Dempe
2021 The Nepali Mathematical Sciences Report  
We present polynomial time solution strategies with orientation dependent transit times by allowing the storage of flow at intermediate nodes.  ...  In this paper, we introduce the maximum dynamic contraflow problem in a general network and earliest arrival contraflow problem in two-terminal series-parallel network with asymmetric transit times on  ...  Because of this, the minimum cost circulation flow problem introduced by Ford and Fulkerson [10] for the maximum dynamic flow problem can be solved in the auxiliary network N .  ... 
doi:10.3126/nmsr.v38i2.42700 fatcat:nyoghnnhr5fvzjx7b3gvwbbfmq

Graph Orientation and Flows over Time [chapter]

Ashwin Arulselvan, Martin Groß, Martin Skutella
2014 Lecture Notes in Computer Science  
We present more results of similar flavor and also show non-approximability results for finding the best orientation for single and multicommodity maximum flows over time.  ...  Thus the question arises, what influence the orientation of the network has on the network flow over time problem that is being solved on the oriented network.  ...  We thank the anonymous reviewers for their helpful comments.  ... 
doi:10.1007/978-3-319-13075-0_58 fatcat:n3c5e4kjobehhagtzj32v6kqja

Graph orientation and flows over time

Ashwin Arulselvan, Martin Groß, Martin Skutella
2015 Networks  
We present more results of similar flavor and also show non-approximability results for finding the best orientation for single and multicommodity maximum flows over time.  ...  Thus the question arises, what influence the orientation of the network has on the network flow over time problem that is being solved on the oriented network.  ...  We thank the anonymous reviewers for their helpful comments.  ... 
doi:10.1002/net.21623 fatcat:n5v4f2zo2ray5b5mwkykrthimm

Network Reconfiguration with Orientation-Dependent Transit Times

Hari Nandan Nath, Urmila Pyakurel, Tanka Nath Dhamala, Fernando Bobillo
2021 International Journal of Mathematics and Mathematical Sciences  
Motivated by applications in evacuation planning, we consider a problem of optimizing flow with arc reversals in which the transit time depends on the orientation of the arc.  ...  The partial contraflow approach for the corresponding problems has also been discussed.  ...  Acknowledgments e first author acknowledges the support of UGC Nepal for Ph.D. fellowship, and the second author acknowledges the support of AvH Foundation for the return fellowship.  ... 
doi:10.1155/2021/6613622 fatcat:eyli22xif5dupjbezb2zg3ncdi

Approximation Scheme for Lowest Outdegree Orientation and Graph Density Measures [chapter]

Łukasz Kowalik
2006 Lecture Notes in Computer Science  
We deal with the problem of finding such an orientation of a given graph that the largest number of edges leaving a vertex (called the outdegree of the orientation) is small.  ...  Our results improve over the previous, 2-approximation algorithms by Aichholzer et al. [1] (for orientation / pseudoarboricity), by Arikati et al. [3] (for arboricity) and by Charikar [5] (for maximum  ...  Further Research We showed how to efficiently approximate the values of arboricity and maximum density.  ... 
doi:10.1007/11940128_56 fatcat:dw6edmjjpvbthmc32cgr3uleny

MAXIMIZING LIFETIME OF HETEROGENEOUS WIRELESS TURNABLE CAMERA SENSOR NETWORKS ENSURING STRONG BARRIER COVERAGE

Nguyen Thi My Binh, Huynh Thi Thanh Binh, Nguyen Hong Ngoc, Mai Dang Quan Anh, Nguyen Khanh Phuong
2021 Journal of Computer Science and Cybernetics  
We formulate the problem, and then propose a Modify Maximum Flow Algorithm (MMFA) consisting of three stages: constructing the flow-network, finding the maximum flow and refining the solution to solve  ...  This paper thus investigates the problem of maximizing the network lifetime to ensure strong barrier coverage for heterogeneous case (MLBC-HWCSN).  ...  We thus devise an approximate algorithm called modified maximum flow (MMFA) for solving the MLBC-HWCSN problem.  ... 
doi:10.15625/1813-9663/37/1/15858 fatcat:jaqc2dr3bngk3ouv2tuipy5oxu

Earliest Arrival of Evacuees with Contraflow Approach

Shiva Prakash Gupta, Shree Ram Khadka
2017 Journal of the Institute of Engineering  
<p>The earliest arrival flow problem sends a maximum number of evacuees as early as possible during the evacuation of people and/or property from dangerous zone to the safe zone.  ...  The problem has been extensively studied as an optimization problem with wide application. In this paper we briefly revisit the existing literature of the problem.  ...  Acknowledgement The research of the first author was supported by University Grant Commission, Sanothimi, Bhaktpur.z  ... 
doi:10.3126/jie.v12i1.16730 fatcat:vusjqxs6xnemtj7vtoavt7lb64

Maximum Balanced Flow in a Network

Haggai Ilani, Michael Lomonosov
2000 Journal of combinatorial theory. Series B (Print)  
We pose a new network flow problem and solve it by reducing to the b-matching problem. The result has application to integer multiflow optimization.  ...  ACKNOWLEDGMENTS The authors appreciate stimulating discussions with Andra s Sebo and his valuable comments and are grateful to the referee who pointed out a serious omission in the proof of the Main Theorem  ...  Consider the following problem. Problem 0 (Maximum Balanced Eulerian Flow).  ... 
doi:10.1006/jctb.1999.1940 fatcat:azi4r4odlnbx7fcjgje2seiyui

Numerical analysis of complex flow of fibre suspensions in a viscoelastic fluid

Fan Xijun
1992 Acta Mechanica Sinica  
This paper describes the mathematical formulation of the flow problems for such a suspension and the numerical procedure to solve them.  ...  A preliminary work done by the author led to a constitutive equation for semiconcentrated fibre suspensions in the Oldroyd-B fluid.  ...  The solution of the same problem for the Oldroyd-B fluid reveals that the drag coefficient of the sphere is 8.The orientation distribution of fibre in the flow field Fig. 3 3 Stream lines for moving  ... 
doi:10.1007/bf02487170 fatcat:2nccvb2xcjclxeqbzcnrqdif4e

Emergent scar lines in chaotic advection of passive directors

Bardia Hejazi, Bernhard Mehlig, Greg A. Voth
2017 Physical Review Fluids  
We examine the spatial field of orientations of slender fibers that are advected by a two-dimensional fluid flow.  ...  We introduce emergent scar lines as the dominant coherent structures in the orientation field of passive directors in chaotic flows.  ...  For passive directors, a flow produces non-trivial patterns in the orientation field even for homogenous initial conditions leading to an entirely new class of problems [1] .  ... 
doi:10.1103/physrevfluids.2.124501 fatcat:wnv65ii2gzdupfpx4c74te6jya

Development and research of the algorithm for determining the maximum flow at distribution in the network

Ainur Akhmediyarova, Dinara Kassymova, Anar Utegenova, Irbulat Utepbergenov
2016 Open Computer Science  
AbstractAn upgraded version of Ford-Fulkerson algorithm is proposed, which allows to determine the maximum flow and the distribution flow in branches of the network.  ...  They show its effectiveness in comparison with the other variants of flow distribution in the network at change of the capacity of branches randomly in time.  ...  This work is financially supported by the grant of Ministry of Education and Science of the Republic of Kazakhstan (grant number 3328/GF4).  ... 
doi:10.1515/comp-2016-0017 fatcat:zmcp7gugafc67dp7zmfnvzbsiy

Graph Orientations Optimizing the Number of Light or Heavy Vertices

Yuichi Asahiro, Jesper Jansson, Eiji Miyano, Hirotaka Ono
2015 Journal of Graph Algorithms and Applications  
A number of results on the computational complexity and polynomial-time approximability of these problems for different values of W and various special classes of graphs are derived.  ...  new generalization of the two latter problems.  ...  Acknowledgments The authors would like to thank Avraham Melkman, Manuel Sorge, and the anonymous reviewers for some insightful comments.  ... 
doi:10.7155/jgaa.00371 fatcat:2qcxqbkia5holly22b3a5k3iri

Graph Orientations Optimizing the Number of Light or Heavy Vertices [chapter]

Yuichi Asahiro, Jesper Jansson, Eiji Miyano, Hirotaka Ono
2012 Lecture Notes in Computer Science  
A number of results on the computational complexity and polynomial-time approximability of these problems for different values of W and various special classes of graphs are derived.  ...  new generalization of the two latter problems.  ...  Acknowledgments The authors would like to thank Avraham Melkman, Manuel Sorge, and the anonymous reviewers for some insightful comments.  ... 
doi:10.1007/978-3-642-32147-4_30 fatcat:z73376oqsrc4zmh5gxxpzrv7la
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