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21
Architectures and Algorithms for FieldProgrammable Gate Arrays with Embedded Memory
, 1997
"... Recent dramatic improvements in integrated circuit fabrication technology have led to FieldProgrammable Gate Arrays (FPGAs) capable of implementing entire digital systems, as opposed to the smaller logic circuits that have traditionally been targeted to FPGAs. Unlike the smaller circuits, these la ..."
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Recent dramatic improvements in integrated circuit fabrication technology have led to FieldProgrammable Gate Arrays (FPGAs) capable of implementing entire digital systems, as opposed to the smaller logic circuits that have traditionally been targeted to FPGAs. Unlike the smaller circuits, these large systems often contain memory. Architectural support for the efficient implementation of memory in nextgeneration FPGAs is therefore crucial. This dissertation examines the architecture of FPGAs with memory,aswell as algorithms that map circuits into these devices. Three aspects are considered: the analysis of circuits that contain memory as well as the automated random generation of such circuits, the architecture and algorithms for standalone con#gurable memory devices, and architect...
Parallel Search for Combinatorial Optimization: Genetic Algorithms, Simulated Annealing, Tabu Search and GRASP
 PROCEEDINGS OF THE SECOND INTERNATIONAL WORKSHOP ON PARALLEL ALGORITHMS FOR IRREGULARLY STRUCTURED PROBLEMS, IRREGULAR'95
, 1995
"... In this paper, we review parallel search techniques for approximating the global optimal solution of combinatorial optimization problems. Recent developments on parallel implementation of genetic algorithms, simulated annealing, tabu search, and greedy randomized adaptive search procedures (GRASP) ..."
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Cited by 17 (2 self)
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In this paper, we review parallel search techniques for approximating the global optimal solution of combinatorial optimization problems. Recent developments on parallel implementation of genetic algorithms, simulated annealing, tabu search, and greedy randomized adaptive search procedures (GRASP) are discussed.
Parallel Metaheuristics for Combinatorial Optimization
 INTERNATIONAL SCHOOL ON ADVANCED ALGORITHMIC TECHNIQUES FOR PARALLEL COMPUTATION WITH APPLICATIONS
, 1999
"... In this paper, we review parallel metaheuristics for approximating the global optimal solution of combinatorial optimization problems. Recent developments on parallel implementation of genetic algorithms, simulated annealing, tabu search, variable neighborhood search, and greedy randomized adapt ..."
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Cited by 11 (2 self)
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In this paper, we review parallel metaheuristics for approximating the global optimal solution of combinatorial optimization problems. Recent developments on parallel implementation of genetic algorithms, simulated annealing, tabu search, variable neighborhood search, and greedy randomized adaptive search procedures (GRASP) are discussed.
Parallel Metaheuristics
, 1997
"... Metaheuristic parallel search methods  tabu search, simulated annealing and genetic algorithms, essentially  are reviewed, classified and examined not according to particular methodological characteristics, but following the unifying approach of the level of parallelization. It is hoped that by ..."
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Cited by 10 (5 self)
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Metaheuristic parallel search methods  tabu search, simulated annealing and genetic algorithms, essentially  are reviewed, classified and examined not according to particular methodological characteristics, but following the unifying approach of the level of parallelization. It is hoped that by examining the commonalities among parallel implementations across the field of metaheuristics, insights may be gained, trends may be discovered, and research challenges may be identified. Particular attention is paid to applications of parallel metaheuristics to transportation problems.
Temperature measurement and equilibrium dynamics of simulated annealing placements
 IEEE Trans. on CAD
, 1990
"... AbstractOne way to alleviate the heavy computation required by simulated annealing placement algorithms is to replace a significant fraction of the higher or middle temperatures with a faster heuristic, and then follow it with simulated annealing. A crucial issue in this approach is the determinat ..."
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Cited by 8 (1 self)
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AbstractOne way to alleviate the heavy computation required by simulated annealing placement algorithms is to replace a significant fraction of the higher or middle temperatures with a faster heuristic, and then follow it with simulated annealing. A crucial issue in this approach is the determination of the starting temperature for the simulated annealing phasea temperature should be chosen that causes an appropriate amount of optimization to he done, but makes good use of the structure provided by the heuristic. This paper presents a method for measuring the temperature of an existing placement. The approach is based on the measurement of the probability distribution of the change in cost function, P(AC), and makes the assumption that the placement is in simulated annealing equilibrium at some temperature. The temperature of placements produced both by a simulated annealing and a mincut placement algorithm are measured, and good agreement with known temperatures is obtained. The P ( A C) distribution
Trading Accuracy for Speed in Parallel Simulated Annealing with Simultaneous Moves
 In
, 2000
"... A common approach to parallelizing simulated annealing to generate several perturbations to the currentsolutionsimultaneously, requiring synchronization to guarantee correct evaluation of the cost function. The cost of this synchronization may be reduced by allowing inaccuracies in the cost calcu ..."
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Cited by 6 (0 self)
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A common approach to parallelizing simulated annealing to generate several perturbations to the currentsolutionsimultaneously, requiring synchronization to guarantee correct evaluation of the cost function. The cost of this synchronization may be reduced by allowing inaccuracies in the cost calculations. We provide a framework for understanding the theoretical implications of this approach based on a model of processor interaction under reduced synchronization that demonstrates how errors in cost calculations occur and how to estimate them. We showhow bounds on error in the cost calculations in asimulated annealing algorithm can be translated into worstcase bounds on perturbations in the parameters which describe the behavior of the algorithm.
Towards Optimal Circuit Layout Using Advanced Search Techniques
 University of Waterloo
, 1995
"... I hereby declare that I am the sole author of this thesis. I authorize the University of Guelph to lend this thesis to other institutions or individuals for the purpose of scholarly research. I further authorize the University of Guelph to reproduce this thesis by photocopying or by other means, in ..."
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Cited by 6 (2 self)
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I hereby declare that I am the sole author of this thesis. I authorize the University of Guelph to lend this thesis to other institutions or individuals for the purpose of scholarly research. I further authorize the University of Guelph to reproduce this thesis by photocopying or by other means, in total or in part, at the request of other institutions or individuals for the purpose of scholarly research. ii The University of Guelph requires the signatures of all persons using or photocopying this thesis. Please sign below, and give address and date. iii iv A VLSI chip can today contain millions of transistors and is expected to contain more than 100 million transistors in the next decade. This tremendous growth is made possible by the development of sophisticated design tools and software. To deal with the complexity
A TwoStage Simulated Annealing Methodology
, 1995
"... We propose a twostage simulated annealing method. While most previous work has focused on ad hoc experimentallyderived constant starting temperatures for the low temperature annealing phase, this paper instead presents a more formal method for generalized starting temperature determination in two ..."
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Cited by 5 (1 self)
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We propose a twostage simulated annealing method. While most previous work has focused on ad hoc experimentallyderived constant starting temperatures for the low temperature annealing phase, this paper instead presents a more formal method for generalized starting temperature determination in twostage simulated annealing systems. We have tested our method on three NPhard optimization problems using both classic and logarithmic cooling schedules. The experimental results have been consistently very goodon average the running time is halved when using a logarithmic cooling schedule and reduced by a third in the case of the classic schedulewith no loss in solution quality. We also present results for an alternative stop criterion used with the classic schedule that further reduces the twostage running time by an additional five to ten percent in our problem suite.
Simulated Annealing with Inaccurate Cost Functions
 in Proceedings of the IMACS International Congress of Mathematics and Computer Science
, 1994
"... . Simulated annealing is an algorithm which generates nearoptimal outcomes to combinatorial optimization problems. It is commonly thought to be slow. Costfunction approximation and parallel processing increase simulated annealing speed, but they can cause inaccuracies that degrade the outcome. Pri ..."
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. Simulated annealing is an algorithm which generates nearoptimal outcomes to combinatorial optimization problems. It is commonly thought to be slow. Costfunction approximation and parallel processing increase simulated annealing speed, but they can cause inaccuracies that degrade the outcome. Prior theoretical work has not adequately related costfunction inaccuracy to the runtime or quality of the outcome. We prove these results about annealing with inaccurate costfunctions: 1) Expected cost at equilibrium is exponentially affected by fl=T , where fl limits costfunction rangeerrors and T gives the temperature. 2) Expected cost at equilibrium is exponentially affected by (oe 2 \Gamma oe 2 )=2T 2 , when the errors have a Gaussian distribution. 3) Constraining fl to a constant factor of T guarantees convergence under a 1= log t temperature schedule. 4) A similar constraint guarantees convergence for a fractal space with a geometric temperature schedule. 5) Inaccuracies worse...
A Parallel RowBased Algorithm For Standard Cell Placement With Integrated Error Control
 in Proc. 26th Design Automation Conf., Las Vegas, NV
, 1989
"... A new rowbased parallel algorithm for standardcell placement targeted for execution on a hypercube multiprocessor is presented. Key features of this implementation include a dynamic simulatedannealing schedule, rowpartitioning of the VLSI chip image, and two novel approaches to control error in ..."
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Cited by 4 (2 self)
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A new rowbased parallel algorithm for standardcell placement targeted for execution on a hypercube multiprocessor is presented. Key features of this implementation include a dynamic simulatedannealing schedule, rowpartitioning of the VLSI chip image, and two novel approaches to control error in parallel cellplacement algorithms: (1) Heuristic CellColoring; (2) Adaptive Sequence Length Control. 1. INTRODUCTION Simulated annealing is a generalpurpose optimization method that has been successfully applied to solve a large variety of combinatorial optimization problems including many in VLSI design. Annealing is computationally very expensive, hence efforts to improve execution time has proceeded along two fronts: (1) accelerating the annealing schedule, and (2) parallelizing the annealing algorithm for execution on multiprocessors. Parallel implementations of annealing as applied to the cell placement application either attempt multiple cell moves in parallel [17], or distribute ...