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Laying Out Sparse Graphs with Provably Minimum Bandwidth

Alberto Caprara, Juan-José Salazar-González
2005 INFORMS journal on computing  
F inding a linear layout of a graph having minimum bandwidth is a combinatorial optimization problem that has been studied since the 1960s.  ...  We show that the resulting method can solve to proven optimality 24 out of the 30 instances from the literature with less than 200 nodes, each in less than a minute on a personal computer.  ...  They are grateful to Federico Malucelli for helpful discussions and to Gianna Del Corso and Giovanni Manzini for providing them with an implementation of their exact algorithm.  ... 
doi:10.1287/ijoc.1040.0083 fatcat:tf2libfozre55gj2teaqzgcnbm

Sparse Signal Recovery and Acquisition with Graphical Models

Volkan Cevher, Piotr Indyk, Lawrence Carin, Richard Baraniuk
2010 IEEE Signal Processing Magazine  
Today's state-of-the-art CS systems can robustly and provably recover K-sparse signals from just M = O(K log(N/K)) noisy measurements using sparsity-seeking, polynomial-time optimization solvers or greedy  ...  An application du jour of the sparse signal recovery problem is compressive sensing (CS), which integrates the sparse representations with two other key aspects of the linear dimensionality reduction:  ...  To complement the above, we also point out some disadvantages of sparse matrices.  ... 
doi:10.1109/msp.2010.938029 fatcat:6bopdzqr4bda3dzpaof2tqnqlq

A survey of direct methods for sparse linear systems

Timothy A. Davis, Sivasankaran Rajamanickam, Wissam M. Sid-Lakhdar
2016 Acta Numerica  
Wilkinson defined a sparse matrix as one with enough zeros that it pays to take advantage of them. 1 This informal yet practical definition captures the essence of the goal of direct methods for solving  ...  sparse matrix problems.  ...  We would like to thank SIAM for their permission to use material for this paper from Davis' book, Direct Methods for Sparse Linear Systems, SIAM, 2006.  ... 
doi:10.1017/s0962492916000076 fatcat:u4dqyjkjqnelll5e3ywm7lqkca

Optimal Direct-Connect Topologies for Collective Communications [article]

Liangyu Zhao and Siddharth Pal and Tapan Chugh and Weiyang Wang and Prithwish Basu and Joud Khoury and Arvind Krishnamurthy
2022 arXiv   pre-print
We provide an algorithmic framework for constructing direct-connect topologies optimized for the latency-bandwidth tradeoff given a collective communication workload.  ...  This research was developed with funding from the Defense Advanced Research Projects Agency (DARPA) under Contract No. HR001120C0089.  ...  Expander 𝑑-regular Graphs Expander graphs are sparse graphs with low modularity, i.e., admit minimal clustering.  ... 
arXiv:2202.03356v1 fatcat:6jbfyyoejfb47nxazqnfxa4uwe

Swarming on Optimized Graphs for n-Way Broadcast

G. Smaragdakis, N. Laoutaris, P. Michiardi, A. Bestavros, J. W. Byers, M. Roussopoulos
2008 IEEE INFOCOM 2008 - The 27th Conference on Computer Communications  
The first one strives to maximize the available bandwidth to the slowest destination, while the second maximizes the aggregate output rate.  ...  We design a swarming protocol suitable for n-way broadcast and operate it on top of overlay graphs formed by nodes that employ Max-Min or Max-Sum policies.  ...  [11] , is that we have substituted the (close to) random graph resulting from BitTorrent's bootstrap and choke/unchoke algorithms with a highly efficient distributively optimized graph.  ... 
doi:10.1109/infocom.2008.37 dblp:conf/infocom/SmaragdakisBLBMR08 fatcat:xlldxvjrszgy3paztip7rk6goe

Swarming on Optimized Graphs for n-Way Broadcast

G. Smaragdakis, N. Laoutaris, P. Michiardi, A. Bestavros, J. W. Byers, M. Roussopoulos
2008 2008 Proceedings IEEE INFOCOM - The 27th Conference on Computer Communications  
The first one strives to maximize the available bandwidth to the slowest destination, while the second maximizes the aggregate output rate.  ...  We design a swarming protocol suitable for n-way broadcast and operate it on top of overlay graphs formed by nodes that employ Max-Min or Max-Sum policies.  ...  [11] , is that we have substituted the (close to) random graph resulting from BitTorrent's bootstrap and choke/unchoke algorithms with a highly efficient distributively optimized graph.  ... 
doi:10.1109/infocom.2007.37 fatcat:vlta55y6vrfqvl7mkltw3koaya

Locally adapted hierarchical basis preconditioning

Richard Szeliski
2006 ACM Transactions on Graphics  
better suited for problems with inhomogeneous (spatially varying) data, smoothness, and boundary constraints.  ...  By looking at the local structure of the coefficient matrix and performing a recursive set of variable eliminations, combined with a simplification of the resulting coarse level problems, we obtain bases  ...  We also compared the time taken with our solver against the sparse linear solver in MatLab.  ... 
doi:10.1145/1141911.1142005 fatcat:y36p64vx5rc6lmmynnk3rwjbzi

Locally adapted hierarchical basis preconditioning

Richard Szeliski
2006 ACM SIGGRAPH 2006 Papers on - SIGGRAPH '06  
better suited for problems with inhomogeneous (spatially varying) data, smoothness, and boundary constraints.  ...  By looking at the local structure of the coefficient matrix and performing a recursive set of variable eliminations, combined with a simplification of the resulting coarse level problems, we obtain bases  ...  We also compared the time taken with our solver against the sparse linear solver in MatLab.  ... 
doi:10.1145/1179352.1142005 fatcat:gewgayqoizbh5jm3xl6o566q5y

Distributed Network Formation for n-Way Broadcast Applications

Georgios Smaragdakis, Nikolaos Laoutais, Pietro Michiardi, Azer Bestavros, John W. Byers, Mema Roussopoulos
2010 IEEE Transactions on Parallel and Distributed Systems  
The first one strives to maximize the available bandwidth to the slowest destination, while the second maximizes the aggregate output rate.  ...  We design a swarming protocol suitable for n-way broadcast and operate it on top of overlay graphs formed by nodes that employ Max-Min or Max-Sum policies.  ...  [16] , is that we have substituted the (close to) random graph resulting from BitTorrent's bootstrap and choke/unchoke algorithms with a highly efficient distributively optimized graph.  ... 
doi:10.1109/tpds.2010.23 fatcat:t7vgq2u6nfa3fcqg4igktvbpy4

Efficient support for client/server applications over heterogeneous ATM networks

O. Gerstel, I. Cidon, S. Zaks
1998 IEEE/ACM Transactions on Networking  
In addition, we propose a new efficient bandwidth allocation scheme which is tailored for client/server applications over ATM networks.  ...  solution, compare their properties, and focus on a novel "greedy" solution, which we prove to optimize certain important criteria (namely, the network overhead for a request/response and the utilization of bandwidth  ...  Our solution is based on three main phases, amongst which the second phase (that deals with laying out the VP's from the clients to the server) is the most complex, and in the second half of the paper  ... 
doi:10.1109/90.720878 fatcat:s6qvxvtkfbgw3kuflk6jvbyd5q

Multi-agent deployment for visibility coverage in polygonal environments with holes

Karl J. Obermeyer, Anurag Ganguli, Francesco Bullo
2011 International Journal of Robust and Nonlinear Control  
This article presents a distributed algorithm for a group of robotic agents with omnidirectional vision to deploy into nonconvex polygonal environments with holes.  ...  As the agents spread out, they claim areas of responsibility (green) which correspond to cells of the incremental partition tree T P .  ...  minimum redundancy requirements.  ... 
doi:10.1002/rnc.1700 fatcat:r4zi3wepefesdhmwyuvheg7kuq

Factor Graphs for Robot Perception

Frank Dellaert, Michael Kaess
2017 Foundations and Trends in Robotics  
The sparse structure of the factor graph is the key to understanding this more general algorithm, and hence also understanding (and improving) sparse factorization methods.  ...  We explain the nonlinear optimization techniques for solving arbitrary nonlinear factor graphs, which requires repeatedly solving large sparse linear systems.  ...  Before we dive in, we first lay out the roadmap for the remainder of the document.  ... 
doi:10.1561/2300000043 fatcat:flxlfe5aerg7ha4zasswzerj3e

Selfish Overlay Network Creation and Maintenance

Georgios Smaragdakis, Nikolaos Laoutaris, Vassilis Lekakis, Azer Bestavros, John W. Byers, Mema Roussopoulos
2011 IEEE/ACM Transactions on Networking  
We demonstrate that EGOIST outperforms existing heuristic overlays on a variety of performance metrics, including delay, available bandwidth, and node utilization, while it remains competitive with an  ...  ., folding new arrivals into an existing overlay, and re-wiring to cope with changing network conditions.  ...  Fig. 8 . 8 Achieving the minimum pairwise delay with constant and with variable out-degree in EGOIST. Fig. 9 . 9 Comparison of update latencies for various neighbor selection strategies.  ... 
doi:10.1109/tnet.2011.2129528 fatcat:skrb5p5qxbhktgesehnyu6qc74

Minimum Cost Blocking Problem in Multi-Path Wireless Routing Protocols

Qi Duan, Mohit Virendra, Shambhu Upadhyaya, Ameya Sanzgiri
2014 IEEE transactions on computers  
We present a class of Minimum Cost Blocking (MCB) problems in Wireless Mesh Networks (WMNs) with multi-path wireless routing protocols.  ...  We establish the provable superiority of multi-path routing protocols over conventional protocols against blocking, node-isolation and network-partitioning type attacks.  ...  We need to find a minimum node cut to separate s 1 and t in the graph with the node C removed.  ... 
doi:10.1109/tc.2013.47 fatcat:c25g3embtngsraiperxgfegizq

Tree Layout for Internal Network Characterizations in Multicast Networks [chapter]

Micah Adler, Tian Bu, Ramesh K. Sitaraman, Don Towsley
2001 Lecture Notes in Computer Science  
With these tools in mind, we focus on the problem of how to lay out multicast sessions so as to cover a set of links of interest within a network.  ...  We establish efficient algorithms to solve the identifiability problem and show that, with few exceptions, the minimum cost problems are NP-hard and that even finding an approximation within a certain  ...  Figure 14 : 14 How to check if the number of flows into and out of a node is valid Minimum cost Multicast Tree Cover Problem.  ... 
doi:10.1007/3-540-45546-9_14 fatcat:hxourut5bnfizft6x4oesxzcqe
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