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15
Differential Evolution  A simple and efficient adaptive scheme for global optimization over continuous spaces
, 1995
"... A new heuristic approach for minimizing possibly nonlinear and non differentiable continuous space functions is presented. By means of an extensive testbed, which includes the De Jong functions, it will be demonstrated that the new method converges faster and with more certainty than Adaptive Simula ..."
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Cited by 276 (4 self)
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A new heuristic approach for minimizing possibly nonlinear and non differentiable continuous space functions is presented. By means of an extensive testbed, which includes the De Jong functions, it will be demonstrated that the new method converges faster and with more certainty than Adaptive Simulated Annealing as well as the Annealed Nelder&Mead approach, both of which have a reputation for being very powerful. The new method requires few control variables, is robust, easy to use and lends itself very well to parallel computation. ________________________________________ 1) International Computer Science Institute, 1947 Center Street, Berkeley, CA 947041198, Suite 600, Fax: 5106437684. Email: storn@icsi.berkeley.edu. On leave from Siemens AG, ZFE T SN 2, OttoHahn Ring 6, D81739 Muenchen, Germany. Fax: 0114963644577, Email: rainer.storn@zfe.siemens.de. 2) 836 Owl Circle, Vacaville, CA 95687, kprice@solano.community.net. Introduction Problems which involve global optimiz...
A SourceBased Algorithm For DelayConstrained MinimumCost Multicasting
, 1995
"... A new heuristic algorithm is presented for constructing minimumcost multicast trees with delay constraints. The new algorithm can set variable delay bounds on destinations and handles two variants of the network cost optimization goal: one minimizing the total cost (total bandwidth utilization) of ..."
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Cited by 54 (0 self)
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A new heuristic algorithm is presented for constructing minimumcost multicast trees with delay constraints. The new algorithm can set variable delay bounds on destinations and handles two variants of the network cost optimization goal: one minimizing the total cost (total bandwidth utilization) of the tree, and another minimizing the maximal link cost (the most congested link). Instead of the singlepass tree construction approach used in most previous heuristics, the new algorithm is based on a feasible search optimization method which starts with the minimumdelay tree and monotonically decreases the cost by iterative improvement of the delaybounded tree. The optimality of the costs of the delaybounded trees obtained with the new algorithm is analyzed by simulation. Depending on how tight the delay bounds are, the costs of the multicast trees obtained with the new algorithm are shown to be very close to the costs of the trees obtained by the Kou, Markowsky and Berman's algorithm. ...
System Design by Constraint Adaptation and Differential Evolution
, 1996
"... A simple optimization procedure for constraint based problems which works without an objective function is described. The absence of an objective function makes the problem formulation particularly simple. The new method lends itself to parallel computation and is well suited for tasks where a famil ..."
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Cited by 50 (0 self)
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A simple optimization procedure for constraint based problems which works without an objective function is described. The absence of an objective function makes the problem formulation particularly simple. The new method lends itself to parallel computation and is well suited for tasks where a family of solutions is required, tradeoff situations have to be dealt with or the design center has to be found. ________________________________________ 1) International Computer Science Institute, 1947 Center Street, Berkeley, CA 947041198, Suite 600, Fax: 5106437684. Email: storn@icsi.berkeley.edu. On leave from Siemens AG, ZFE T SN 2, OttoHahn Ring 6, D81739 Muenchen, Germany. Fax: 0114963644577, Email: rainer.storn@zfe.siemens.de. 2 1. Introduction The design of a technical system is usually associated with the process of properly choosing some system parameters such that the technical system meets its specifications. The parameter choosing process can also be regarded as an o...
An Iterative Algorithm for DelayConstrained MinimumCost Multicasting
 IEEE/ACM Transactions on Networking
, 1998
"... The bounded shortest multicast algorithm (BSMA) is presented for constructing minimumcost multicast trees with delay constraints. BSMA can handle asymmetric link characteristics and variable delay bounds on destinations, specified as real values, and minimizes the total cost of a multicast routing ..."
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Cited by 45 (1 self)
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The bounded shortest multicast algorithm (BSMA) is presented for constructing minimumcost multicast trees with delay constraints. BSMA can handle asymmetric link characteristics and variable delay bounds on destinations, specified as real values, and minimizes the total cost of a multicast routing tree. Instead of the singlepass tree construction approach used in most previous heuristics, the new algorithm is based on a feasiblesearch optimization strategy that starts with the minimumdelay multicast tree and monotonically decreases the cost by iterative improvement of the delaybounded multicast tree. BSMA's expected time complexity is analyzed, and simulation results are provided showing that BSMA can achieve nearoptimal cost reduction with fast execution.
ReliabilityConstrained Area Optimization of VLSI Power/Ground Networks Via Sequence of Linear Programmings
 IEEE Trans. on ComputerAided Design of Integrated Circuits and Systems
, 1999
"... This paper presents a new method for determining the widths of the power and ground routes in integrated circuits so that the area required by the routes is minimized subject to the reliability constraints. The basic idea is to transform the resulting constrained nonlinear programming problem into a ..."
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Cited by 32 (0 self)
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This paper presents a new method for determining the widths of the power and ground routes in integrated circuits so that the area required by the routes is minimized subject to the reliability constraints. The basic idea is to transform the resulting constrained nonlinear programming problem into a sequence of linear programs. Theoretically, we show that the sequence of linear programs always converges to the optimum solution of the relaxed convex problem. Experimental results demonstrate that the sequenceoflinearprogramming method is orders of magnitude faster than the bestknown method based on conjugate gradients, with constantly better optimization solutions.
WorstCase Analysis and Optimization of VLSI Circuit Performances
, 1995
"... In this paper, we present a new approach for realistic worstcase analysis of VLSI circuit performances and a novel methodology for circuit performance optimization. Circuit performance measures are modeled as response surfaces of the designable and uncontrollable (noise) parameters. Worstcase anal ..."
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Cited by 19 (1 self)
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In this paper, we present a new approach for realistic worstcase analysis of VLSI circuit performances and a novel methodology for circuit performance optimization. Circuit performance measures are modeled as response surfaces of the designable and uncontrollable (noise) parameters. Worstcase analysis proceeds by first computing the worstcase circuit performance value and then determining the worstcase noise parameter values by solving a nonlinear programming problem. A new circuit optimization technique is developed to find an optimal design point at which all of the circuit specifications are met under worstcase conditions. This worstcase design optimization method is formulated as a constrained multicriteria optimization. The methodologies described in this paper are applied to several VLSI circuits to demonstrate their accuracy and efficiency. Keywords Worstcase analysis, worstcase design optimization. I. Introduction I NEVITABLE fluctuations in the manufacturing proces...
An SQP Algorithm For Finely Discretized Continuous Minimax Problems And Other Minimax Problems With Many Objective Functions
, 1996
"... . A common strategy for achieving global convergence in the solution of semiinfinite programming (SIP) problems, and in particular of continuous minimax problems, is to (approximately) solve a sequence of discretized problems, with a progressively finer discretization meshes. Finely discretized min ..."
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Cited by 17 (2 self)
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. A common strategy for achieving global convergence in the solution of semiinfinite programming (SIP) problems, and in particular of continuous minimax problems, is to (approximately) solve a sequence of discretized problems, with a progressively finer discretization meshes. Finely discretized minimax and SIP problems, as well as other problems with many more objectives /constraints than variables, call for algorithms in which successive search directions are computed based on a small but significant subset of the objectives/constraints, with ensuing reduced computing cost per iteration and decreased risk of numerical difficulties. In this paper, an SQPtype algorithm is proposed that incorporates this idea in the particular case of minimax problems. The general case will be considered in a separate paper. The quadratic programming subproblem that yields the search direction involves only a small subset of the objective functions. This subset is updated at each iteration in such a wa...
Optimal Sizing of High Speed Clock Networks Based on Distributed RC and Lossy Transmission Line Models
 In Proceedings of the IEEE International Conference on Computer Aided Design
, 1993
"... This paper formulates the optimal sizing of a general clock network as an optimization problem which minimizes the clock skew in a feasible set of widths. This feasible set of branch widths is decided by the process technology and routing resources. The skew minimization problem is turned into a lea ..."
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Cited by 11 (5 self)
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This paper formulates the optimal sizing of a general clock network as an optimization problem which minimizes the clock skew in a feasible set of widths. This feasible set of branch widths is decided by the process technology and routing resources. The skew minimization problem is turned into a leastsquares estimation problem, and a modified GaussMarquardt's method is then used to determine the optimal widths of clock branches. This optimization method combines the best features of the methods based on Taylor series and methods based on gradients. An efficient algorithm is also proposed that assigns the good initial widths especially for a clock tree which let the later optimization process converge much more quickly. Our method is very flexible and can handle the general clock network including loops. The clock network can exhibit distributed RC and lossy transmission line behaviors. The method employs a scatteringparameters based delay macromodel to evaluate the timing of the clock network during the optimization process. The major objective of our sizing method is to minimize the skew, but as a byproduct that the largest path delay is also reduced.
FASY: A fuzzylogic based tool for analog synthesis
 IEEE Transactions on ComputerAided Design of Integrated Circuits
, 1996
"... A CAD tool for analog circuit synthesis is presented. This tool, called FASY, uses fuzzy–logic based reasoning to select one topology among a fixed set of alternatives. For the selected topology, a two–phase optimizer sizes all elements to satisfy the performance constrains minimizing a cost functio ..."
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Cited by 10 (0 self)
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A CAD tool for analog circuit synthesis is presented. This tool, called FASY, uses fuzzy–logic based reasoning to select one topology among a fixed set of alternatives. For the selected topology, a two–phase optimizer sizes all elements to satisfy the performance constrains minimizing a cost function. In FASY, the decision rules used in the topology selection process are introduced by an expert designer or automatically generated by means of a learning process that uses the optimizer mentioned above. The capability of learning topology selection rules by experience, is unique in FASY. Practical examples demonstrate the tool ability of this tool to learn topology selection rules and to synthesize analog cells with different circuit topologies. 1 1
MIDAS  a functional simulator for mixed digital and analog sampled data systems
, 1995
"... Automatic Synthesis of CMOS Digital/Analog Converters by Robert McKinstry Robinson Neff Doctor of Philosophy in Engineering  Electrical Engineering and Computer Sciences University of California at Berkeley Professor Paul R. Gray, Chair Synthesis of analog functional blocks in integrated ci ..."
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Cited by 6 (1 self)
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Automatic Synthesis of CMOS Digital/Analog Converters by Robert McKinstry Robinson Neff Doctor of Philosophy in Engineering  Electrical Engineering and Computer Sciences University of California at Berkeley Professor Paul R. Gray, Chair Synthesis of analog functional blocks in integrated circuits offers promise for improved designer productivity. By developing module generators for commonly used analog circuit elements, a synthesis methodology may be matched to a particular application, with approaches and algorithms determined by the particular needs of target circuit type. An analog circuit designer should be able to input design specifications and underlying technology information, and a synthesis methodology should determine circuit parameter values and dimensions, creating the required mask layouts. Slow, tedious design and redesign methods should be replaced by one in which the computer finds minimum cost designs which meet performance requirements. This work implements synthesis methods for a widely used analog block, the digital/analog converter (DAC).