Search results for "Electronic Design Automation"
showing 10 items of 118 documents
Polyhedral results for a vehicle routing problem
1991
Abstract The Vehicle Routing Problem is a well known, and hard, combinatorial problem, whose polyhedral structure has deserved little attention. In this paper we consider the particular case in which all the demands are equal (since in the general case the associated polytope may be empty). From a known formulation of the problem we obtain the dimension of the corresponding polytope and we study the facetial properties of every inequality in it.
Optimal Configuration for N-Dimensional Twin Torus Networks
2014
Torus topology is one of the most common topologies used in the current largest supercomputers. Although 3D torus is widely used, recently some supercomputers in the Top500 list have been built using networks with topologies of five or six dimensions. To obtain an nD torus, 2n ports per node are needed. These ports can be offered by a single or several cards per node. In the second case, there are multiple ways of assigning the dimension and direction of the card ports. In a previous work we proposed the 3D Twin (3DT) torus which uses two 4-port cards per node, and obtained the optimal port configuration. This paper extends and generalizes that work in order to obtain the optimal port confi…
Advances in vehicle routing and logistics optimization
2019
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Run-time scalable NoC for FPGA based virtualized IPs
2017
The integration of virtualized FPGA-based hardware accelerators in a cloud computing is progressing from time to time. As the FPGA has limited resources, the dynamic partial reconfiguration capability of the FPGA is considered to share resources among different virtualized IPs during runtime. On the other hand, the NoC is a promising solution for communication among virtualized FPGA-based IPs. However, not all the virtualized regions of the FPGA will be active all the time. When there is no demand for virtualized IPs, the virtualized regions are loaded with blank bitstreams to save power. However, keeping active the idle components of the NoC connecting with the idle virtualized regions is …
A self-routing protocol for distributed consensus on logical information
2010
In this paper, we address decision making problems, depending on a set of input events, with networks of dynamic agents that have partial visibility of such events. Previous work by the authors proposed so-called logical consensus approach, by which a network of agents, that can exchange binary values representing their local estimates of the events, is able to reach a unique and consistent decision. The approach therein proposed is based on the construction of an iterative map, whose computation is centralized and guaranteed under suitable conditions on the input visibility and graph connectivity. Under the same conditions, we extend the approach in this work by allowing the construction o…
Time-Dependent Multiple Depot Vehicle Routing Problem on Megapolis Network under Wardrop's Traffic Flow Assignment
2018
In this work multiple depot vehicle routing problem is considered in case of variable travel times between nodes on a metropolis network. This variant of the classic multiple depot vehicle routing problem is motivated by the fact that in urban contexts variable traffic conditions play an essential role and can not be ignored in order to perform a realistic optimization. Time-travel matrices corresponding to each period of planning horizon were formed by solving the traffic assignment problem in conjunction with shortest path problem. Routing problem instances include from 20 to 100 customers randomly chosen from a road network of Saint-Petersburg. The results demonstrate that taking into ac…
Heuristics for the bi-objective path dissimilarity problem
2009
In this paper the path dissimilarity problem is considered. The problem has previously been studied within several contexts, the most popular of which is motivated by the need to select transportation routes for hazardous materials. The aim of this paper is to formally introduce the problem as a bi-objective optimization problem, in which a single solution consists of a set of p different paths, and two conflicting objectives arise, on one hand the average length of the paths must be kept low, and on the other hand the dissimilarity among the paths in the set should be kept high. Previous methods are reviewed and adapted to this bi-objective problem, thus we can compare the methods using th…
Achieving Unbounded Resolution inFinitePlayer Goore Games Using Stochastic Automata, and Its Applications
2012
Abstract This article concerns the sequential solution to a distributed stochastic optimization problem using learning automata and the Goore game (also referred to as the Gur game in the related literature). The amazing thing about our solution is that, unlike traditional methods, which need N automata (where N determines the degree of accuracy), in this article, we show that we can obtain arbitrary accuracy by recursively using only three automata. To be more specific, the Goore game (GG) introduced in Tsetlin (1973) has the fascinating property that it can be resolved in a completely distributed manner with no inter-communication between the players. The game has recently found applicati…
Models and solution methods for the uncapacitatedr-allocationp-hub equitable center problem
2017
Hub networks are commonly used in telecommunications and logistics to connect origins to destinations in situations where a direct connection between each origin–destination (o-d) pair is impractical or too costly. Hubs serve as switching points to consolidate and route traffic in order to realize economies of scale. The main decisions associated with hub-network problems include (1) determining the number of hubs (p), (2) selecting the p-nodes in the network that will serve as hubs, (3) allocating non-hub nodes (terminals) to up to r-hubs, and (4) routing the pairwise o-d traffic. Typically, hub location problems include all four decisions while hub allocation problems assume that the valu…
Evaluation of a Real, Low Cost, Urban WSN Deployment for Accurate Environmental Monitoring
2011
There are many areas where Wireless Sensor Networks (WSN) can offer innovative solutions for environmental monitoring applications and the meteorological community, but due to their complexity in terms of energy constraints and low performance devices, very few real deployments can be found. In this paper we will explain in detail the design, implementation and performance evaluation of a sparse WSN that has been working maintenance-free for over 12 months. The network has been designed for environmental monitoring purposes, and several motes, attached to lampposts, accurately measure the Temperature and Relative Humidity at various locations in a local street. Our contribution is an enhanc…