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On an Online Spanning Tree Problem in Randomly Weighted Graphs

JAN REMY, ALEXANDER SOUZA, ANGELIKA STEGER
2006 Combinatorics, probability & computing  
This paper is devoted to an online variant of the minimum spanning tree problem in randomly weighted graphs.  ...  An algorithm receives the edges one by one and has to decide immediately whether to include the current edge into the spanning tree or to reject it.  ...  The problem of finding a minimum spanning tree in graphs is one of the classical problems in combinatorial optimization and thus well studied.  ... 
doi:10.1017/s096354830600770x fatcat:2tikxiyo5rdgte5z53qqtbpyay

Dynamic Network Formation for FSO Satellite Communication

Revital Marbel, Roi Yozevitch, Tal Grinshpoun, Boaz Ben-Moshe
2022 Applied Sciences  
Based on a large number of simulations, we conclude that, although the underlying problem of bounded-degree-spanning-tree is NP-hard (even for static cases), the suggested ant-colony heuristic is able  ...  Moreover, classical communication optimization methods, such as Minimal Spanning Tree, cannot be applied directly in dynamic scenarios where the satellite constellation is constantly changing.  ...  A simpler version of this problem is well known in the literature as the Minimum Spanning Tree (or MST) problem [22] . As mentioned above, static graphs are graphs with static (unchanging) weights.  ... 
doi:10.3390/app12020738 fatcat:zm4gs7agbzakfpsd3dlcvequ4e

Fast and Robust Graph-based Transductive Learning via Minimum Tree Cut

Yan-Ming Zhang, Kaizhu Huang, Cheng-Lin Liu
2011 2011 IEEE 11th International Conference on Data Mining  
After approximating a graph with a spanning tree, we develop a linear-time algorithm to label the tree such that the cut size of the tree is minimized.  ...  In this paper, we propose an efficient and robust algorithm for graph-based transductive classification.  ...  [6] extended the work of [11] from the un-weighted graph to the weighted one, and shown the cumulative errors of their algorithm is bounded in terms of the cut size of a random spanning tree.  ... 
doi:10.1109/icdm.2011.66 dblp:conf/icdm/ZhangHL11 fatcat:bv4dckv7bffefp5ox2djoc6a5e

Online broadcasting and multicasting in WDM networks with shared light splitter bank

Weifa Liang, Yuzhen Liu
2007 2007 Fourth International Conference on Broadband Communications, Networks and Systems (BROADNETS '07)  
In this paper we deal with online broadcasting and multicasting in a WDM optical network with shared light splitter bank. Our objective is to maximize the network throughput.  ...  We then show that under either of the two proposed cost models, finding a cost-optimal broadcast or multicast tree for a broadcast or multicast request is NP-complete, and instead devise approximation  ...  Approximation algorithm for degree-constrained broadcast trees Given an undirected graph G(V, E, d ), each node v ∈ V is bounded by an integer 1 ≤ d (v) ≤ d v , the problem is to construct a spanning tree  ... 
doi:10.1109/broadnets.2007.4550475 dblp:conf/broadnets/LiangL07 fatcat:ilcfyyt7ijdglcl4jj4v7g3xua

Online Multicasting in WDM Networks with Shared Light Splitter Bank [chapter]

Yuzhen Liu, Weifa Liang
2007 Lecture Notes in Computer Science  
Instead, it either accepts the request by building an economic multicast tree for the request, in terms of the utilization of the network resources if it has sufficient resources available, or rejects  ...  In this article we first propose a cost model for realizing an online multicast request under such network environments with limited light splitters and wavelength converters, which models the cost of  ...  The node-weighted Steiner tree problem is to find a tree in G spanning all the nodes in terminal set D such that the weighted sum of the nodes in the tree is minimized.  ... 
doi:10.1007/978-3-540-72606-7_82 fatcat:kx44tvdqmvcqpkur5lbjd2akuu

Online multicasting in WDM networks with shared light splitter bank

Yuzhen Liu, Weifa Liang
2008 Photonic network communications  
Instead, it either accepts the request by building an economic multicast tree for the request, in terms of the utilization of the network resources if it has sufficient resources available, or rejects  ...  In this article we first propose a cost model for realizing an online multicast request under such network environments with limited light splitters and wavelength converters, which models the cost of  ...  The node-weighted Steiner tree problem is to find a tree in G spanning all the nodes in terminal set D such that the weighted sum of the nodes in the tree is minimized.  ... 
doi:10.1007/s11107-008-0138-x fatcat:ufbftheipjcjpengnrtz2qs4w4

Robust Lineage Reconstruction from High-Dimensional Single-Cell Data [article]

Gregory Giecold, Eugenio Marco, Lorenzo Trippa, Guo-Cheng Yuan
2016 bioRxiv   pre-print
Such uncertainties have not been taken into account in current methods.  ...  ECLAIR uses an ensemble approach to improve the robustness of lineage predictions, and provides a quantitative estimate of the uncertainty of lineage branchings.  ...  Figure S3 : S3 A schematic showing the minimum spanning tree is sensitive to small perturbation of the edge weights. (A,B) Two graphs with continuous edge weights.  ... 
doi:10.1101/036533 fatcat:iweohj7vvjhbjnvwzqs26uqnim

Evolutionary Local Search for Designing Peer-to-Peer Overlay Topologies Based on Minimum Routing Cost Spanning Trees [chapter]

Peter Merz, Steffen Wolf
2006 Lecture Notes in Computer Science  
An example of such a graph is a spanning tree connecting all nodes in the overlay.  ...  Finding overlay topologies for peer-to-peer networks on top of the Internet can be regarded as a network design problem, in which a graph with minimum communication costs is desired.  ...  In section 2, an overview is given for network optimization problems with focus on the minimum routing cost spanning tree (MRT) problem as well as local search algorithms.  ... 
doi:10.1007/11844297_28 fatcat:v6ob4qazdzgt7aqifqod5txi6u

Online Multicasting for Network Capacity Maximization in Energy-Constrained Ad Hoc Networks

Weifa Liang, Xiaoxing Guo
2006 IEEE Transactions on Mobile Computing  
Specifically, we first propose an online algorithm for the problem based on an exponential function of energy utilization at each node.  ...  This is in contrast to the implication by Kar et al. that the network lifetime is proportional to the network capacity when they considered the online unicast routing by devising an algorithm based on  ...  Fortunately, through the construction of an auxiliary graph, we can transform a nodeweighted multicast tree problem in the original network into an edge-weighted multicast tree problem equivalently in  ... 
doi:10.1109/tmc.2006.133 fatcat:htmssdrkgzc7fixuzb5gy5fusq

On-line network optimization problems [chapter]

Bala Kalyanasundaram, Kirk Pruhs
1998 Lecture Notes in Computer Science  
We survey results on online versions of the standard network optimization problems, including the minimum spanning tree problem, the minimum Steiner tree problem, the weighted and unweighted matching problems  ...  The goal in these problems is to maintain, with minimal changes, a low cost subgraph of some type in a dynamically changing network.  ...  The particular types of subgraphs we consider are unweighted matchings, weighted matchings, tours, spanning trees, k-connected spanning graphs, Steiner trees, and generalized Steiner trees.  ... 
doi:10.1007/bfb0029573 fatcat:kdh23xb4mnbelhcim36r6httea

GSST: anytime guaranteed search

Geoffrey Hollinger, Athanasios Kehagias, Sanjiv Singh
2010 Autonomous Robots  
The problem is as follows: clear the environment of any adversarial target using the fewest number of searchers. This problem is NP-hard on arbitrary graphs but can be solved in linear-time on trees.  ...  We present Guaranteed Search with Spanning Trees (GSST), an anytime algorithm for multi-robot search.  ...  Thanks to volunteer firefighter (and professional roboticist) Seth Koterba for feedback on the system. Parts of this work utilized Jonathan Richard Shewchuk's free Delaunay triangulation software.  ... 
doi:10.1007/s10514-010-9189-9 fatcat:idmfemntb5dgvbvitu3yifgbfe

Incremental Object Discovery in Time-Varying Image Collections

Theodora Kontogianni, Markus Mathias, Bastian Leibe
2016 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)  
In this paper, we address the problem of object discovery in time-varying, large-scale image collections.  ...  Our proposed tree structure can be created in a local neighborhood of the matching graph during image retrieval and can be efficiently updated whenever the image database is extended.  ...  As such, it is not possible to use MS directly on G (at this point G is not fully connected). The spanning tree construction is necessary in order to circumvent this problem.  ... 
doi:10.1109/cvpr.2016.229 dblp:conf/cvpr/KontogianniML16 fatcat:h4enqxfbsnfzjg3bv4oiy4u2vm

The regenerator location problem

Si Chen, Ivana Ljubić, S. Raghavan
2009 Networks  
We show how to represent the RLP as a max leaf spanning tree problem (MLSTP) on a transformed graph.  ...  In this paper we introduce the regenerator location problem (RLP), which deals with a constraint on the geographical extent of transmission in optical networks.  ...  To ensure feasibility, we first construct an arbitrary spanning tree over the n nodes. We then randomly generate 1) ) edges and add them to the spanning tree generated previously.  ... 
doi:10.1002/net.20366 fatcat:xjmt7vfcoratdeq7ybwjo55diq

Maximizing Throughput in Layered Peer-to-Peer Streaming

L. Dai, Y. Cui, Y. Xue
2007 2007 IEEE International Conference on Communications  
Layered streaming is an effective solution to address the receiver heterogeneity in peer-to-peer (P2P) multimedia distribution.  ...  We formulate the problem using the multicommodity flow theory, and propose a series of routing algorithms that fully explore the tradeoff between theoretical optimality and practicability.  ...  On top of each overlay graph, different spanning trees can be found. Fig. 2 shows a sample spanning tree for the overlay graphs G(a) and G(b) in Fig. 1 .  ... 
doi:10.1109/icc.2007.290 dblp:conf/icc/DaiCX07 fatcat:hfgjvgvh7ngq7gaycqlle7mpsa

Constructing low-latency overlay networks: Tree vs. mesh algorithms

Knut-Helge Vik, Carsten Griwodz, Pal Halvorsen
2008 2008 33rd IEEE Conference on Local Computer Networks (LCN)  
In particular, we focus on reducing the diameter and the pair-wise latencies in the overlay.  ...  We found that trees are faster to construct and save considerable amounts of resources in the network.  ...  Formally, an MDST-algorithm constructs a spanning tree T on G such that the maximum weight shortest path (diameter) p ∈ T , e∈p W (e) is minimized.  ... 
doi:10.1109/lcn.2008.4664149 dblp:conf/lcn/VikGH08 fatcat:fp2lr37ht5enho7ebxfxzsrwbe
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