ABSTRACT This paper develops a deterministic heuristic based on a continuous quadratic nonconvex ... more ABSTRACT This paper develops a deterministic heuristic based on a continuous quadratic nonconvex formulation of the maximum clique problem. The developed heuristic avoids the need for the calibration of parameters while maintaining computational competitiveness to greedy randomized search procedures which require such calibration. Furthermore, it demonstrates the potential for using continuous approaches to model discrete problems. Experimental results on test problems are presented.
Proceedings of SPIE - The International Society for Optical Engineering, 2007
abstract This paper deals with the progress made in applications of quantum computing in control ... more abstract This paper deals with the progress made in applications of quantum computing in control and optimization. It concentrates on applying the geometric technique in order to investigate a finite control problem of a two-level quantum system, resonance control of a three-level system, simulation of bilinear quantum control systems, and optimal control using the Bellman principle. We show that a quantum object described by a Schroedinger equation can be controlled in an optimal way by electromagnetic modes. We also ...
Graph radio coloring and graph radio labelling are combinatorial models for two interesting cases... more Graph radio coloring and graph radio labelling are combinatorial models for two interesting cases of Frequency Assignment. In both problems positive integer labels (channels) must be assigned to all the vertices of a graph such that adjacent vertices get labels at distance at least two. In radio labelling all the labels must be distinct, while in radio coloring only the vertices being at distance no more than two in the input graph must be assigned distinct labels. For both problems the objective is to minimize the maximum label used.
Computational Intelligence and Optimization Methods for Control Engineering, 2019
Controller performance is evaluated with the properties of steady-state and transient response of... more Controller performance is evaluated with the properties of steady-state and transient response of the system at the time domain. The compensators and conventional controllers like PID are designed, so that the desired performance is reached only by adjusting the controller parameters; this adjustment mechanism is called tuning. Even many approaches are proposed for tuning; still, it remains one of the problems of control theory due to the imperfect modeling, disturbance, and problem complexity. At this stage, optimization algorithms have helped the researchers to find these parameters via designing objective function concerning the time response characteristics of the system. As the expectations (for example, steady-state error, overshoot, rise time, settling time) related to the system performance are increased in number, the number of objectives is also increased. As a result, multi-objective optimization algorithms have applied to solve these problems. In this chapter, a set of benchmark tuning problems is defined as the test—benchmark—problems. Then, by using the multi- and many-objective optimization algorithms, the performance of the controlled system with respect to the Pareto approximate set is compared with each other. The multi/many-objective optimization algorithms evaluated in this chapter are as follows: Multi-objective Evolutionary Algorithm based on Decomposition (MOEAD), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Multi-objective Particle Swarm Optimization (MOPSO), Strength Pareto Evolutionary Algorithm 2 (SPEA2), Approximation-guided Evolutionary Algorithm II (AGE-II), and Reference Vector Guided Evolutionary Algorithm (RVEA).
Analytical and discrete optimization approaches for routing an aircraft in a threat environment h... more Analytical and discrete optimization approaches for routing an aircraft in a threat environment have been developed. Using these approaches, an aircraft's optimal risk trajectory with a constraint on the path length can be efficiently calculated. The analytical approach based on calculus of variations reduces the original risk optimization problem to the system of nonlinear differential equations. In the case of a single radarinstallation, the solution of such a system is expressed by the elliptic sine. The discrete optimization ...
In this paper we introduce the two-stage stochastic graph partitioning problem and present the st... more In this paper we introduce the two-stage stochastic graph partitioning problem and present the stochastic mixed integer programming formulation for this problem with finite explicit scenarios. For solving this problem, we present an equivalent integer linear programming formulation where some binary variables are relaxed to continuous ones. Additionally, for some specific graphs, we present a more simplified linear programming formulation. All formulations are tested on randomly generated graphs with different densities and ...
ABSTRACT This paper develops a deterministic heuristic based on a continuous quadratic nonconvex ... more ABSTRACT This paper develops a deterministic heuristic based on a continuous quadratic nonconvex formulation of the maximum clique problem. The developed heuristic avoids the need for the calibration of parameters while maintaining computational competitiveness to greedy randomized search procedures which require such calibration. Furthermore, it demonstrates the potential for using continuous approaches to model discrete problems. Experimental results on test problems are presented.
Proceedings of SPIE - The International Society for Optical Engineering, 2007
abstract This paper deals with the progress made in applications of quantum computing in control ... more abstract This paper deals with the progress made in applications of quantum computing in control and optimization. It concentrates on applying the geometric technique in order to investigate a finite control problem of a two-level quantum system, resonance control of a three-level system, simulation of bilinear quantum control systems, and optimal control using the Bellman principle. We show that a quantum object described by a Schroedinger equation can be controlled in an optimal way by electromagnetic modes. We also ...
Graph radio coloring and graph radio labelling are combinatorial models for two interesting cases... more Graph radio coloring and graph radio labelling are combinatorial models for two interesting cases of Frequency Assignment. In both problems positive integer labels (channels) must be assigned to all the vertices of a graph such that adjacent vertices get labels at distance at least two. In radio labelling all the labels must be distinct, while in radio coloring only the vertices being at distance no more than two in the input graph must be assigned distinct labels. For both problems the objective is to minimize the maximum label used.
Computational Intelligence and Optimization Methods for Control Engineering, 2019
Controller performance is evaluated with the properties of steady-state and transient response of... more Controller performance is evaluated with the properties of steady-state and transient response of the system at the time domain. The compensators and conventional controllers like PID are designed, so that the desired performance is reached only by adjusting the controller parameters; this adjustment mechanism is called tuning. Even many approaches are proposed for tuning; still, it remains one of the problems of control theory due to the imperfect modeling, disturbance, and problem complexity. At this stage, optimization algorithms have helped the researchers to find these parameters via designing objective function concerning the time response characteristics of the system. As the expectations (for example, steady-state error, overshoot, rise time, settling time) related to the system performance are increased in number, the number of objectives is also increased. As a result, multi-objective optimization algorithms have applied to solve these problems. In this chapter, a set of benchmark tuning problems is defined as the test—benchmark—problems. Then, by using the multi- and many-objective optimization algorithms, the performance of the controlled system with respect to the Pareto approximate set is compared with each other. The multi/many-objective optimization algorithms evaluated in this chapter are as follows: Multi-objective Evolutionary Algorithm based on Decomposition (MOEAD), Non-dominated Sorting Genetic Algorithm II (NSGA-II), Multi-objective Particle Swarm Optimization (MOPSO), Strength Pareto Evolutionary Algorithm 2 (SPEA2), Approximation-guided Evolutionary Algorithm II (AGE-II), and Reference Vector Guided Evolutionary Algorithm (RVEA).
Analytical and discrete optimization approaches for routing an aircraft in a threat environment h... more Analytical and discrete optimization approaches for routing an aircraft in a threat environment have been developed. Using these approaches, an aircraft's optimal risk trajectory with a constraint on the path length can be efficiently calculated. The analytical approach based on calculus of variations reduces the original risk optimization problem to the system of nonlinear differential equations. In the case of a single radarinstallation, the solution of such a system is expressed by the elliptic sine. The discrete optimization ...
In this paper we introduce the two-stage stochastic graph partitioning problem and present the st... more In this paper we introduce the two-stage stochastic graph partitioning problem and present the stochastic mixed integer programming formulation for this problem with finite explicit scenarios. For solving this problem, we present an equivalent integer linear programming formulation where some binary variables are relaxed to continuous ones. Additionally, for some specific graphs, we present a more simplified linear programming formulation. All formulations are tested on randomly generated graphs with different densities and ...
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Papers by Panos Pardalos