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This research presents a theoretical investigation on the performance of a vapour compression refrigerating system using different mixtures of Hydrocarbons and Hydrofluorocarbons refrigerants as a refrigerant. Genetic Algorithm method was used to solve a nonlinear constrained optimization problem for the selection of the best blend. The performance of new mixtures of Hydrocarbons and Hydrofluorocarbons...
The Reactive Power Dispatch (RPD) problem is a nonlinear constrained optimization problem. This paper presents a multi-objective solution set for RPD problem. The objective functions are minimization of real power loss and minimization of control variable adjustment costs. This paper has considered the setting of Flexible AC Transmission System (FACTS) device as additional control parameter in the...
When the present channel used by the secondary user (SU) is detected to be busy due to the re-appearance of the primary user (PU) in cognitive radios, the SU has to search an out-band so that its transmission can be continued. In order to meet the QoS requirement, out-band sensing speed should be as fast as possible. How to reduce out-band sensing time employing cooperative spectrum sensing is proposed...
For the speed control of film winding system, the pseudo-derivative feedback (PDF) controller is first selected. Controller parameters tuning then becomes a nonlinear constrained optimization problem with nonlinearity and load variations of film winding system. To avoid the selection of penalty parameters in constraint handling, NSGA-II is utilized by converting the nonlinear constrained optimization...
The paper presents a new hybrid global optimization algorithm based on chaos search and complex method for nonlinear constrained optimization problems. To fit for chaos optimization algorithm, a constrained optimization problem is transformed into an unconstrained problem by penalty function method. The mapping mode of standard complex method is improved to solve the problem of low computational efficiency...
Advanced structural ceramics are widely used in engineering applications. They are useful due to high chemical inertness and sublimation temperature. Optimization of ceramic grinding process is essential as ceramics have high hardness and low surface toughness which can lead to large number of defects. The ceramic grinding optimization problem is formulated as non-linear constrained optimization problem...
In this work the multiarea optimal power flow (OPF) problem is decoupled into areas creating a set of regional OPF subproblems. The objective is to solve the optimal dispatch of active and reactive power for a determined area, without interfering in the neighboring areas. The regional OPF subproblems are modeled as a large-scale nonlinear constrained optimization problem, with both continuous and...
This paper presents an approach to solve the online transient stability constrained power generation (TSCPG) by a mixture of a modified particle swarm optimization (PSO) and artificial neural network (ANN). This mixture (PSO-ANN) has been used as optimization tool to guarantee searching the optimal solution within the hyperspace reducing the time consumed in the computations and improving the quality...
The reactive power allocation aspect has received considerable attention in present day power system operation and control. At heavy/light load periods, voltage control is provided by the controllable reactive sources, which are scattered throughout the transmission network, function in co-ordination. Reactive power dispatch problem can be formulated as a nonlinear constrained optimization problem...
We present a collaborated camouflaging mobility algorithm to protect mobile hosts' mobility privacy. Our algorithm alters a mobile host's straight moving paths into Delta-shaped camouflaging paths, which cause its wireless transmissions to be distributed over a large area, and hence, reduce the probability of generating traceable wireless transmissions. Furthermore, on the premise of not affecting...
The paper presents a novel method which generates hopping gaits for an articulated single leg. Inspired by human running, the flight phase is assumed to be nearly-passive. Consequently, the initial joint velocities of the flight phase can be solved by using a static optimization procedure, provided that the boundary joint angles have been picked in advance. The two hopping phases can then be dynamically...
The problem of choosing the optimal location and size for shunt capacitors in unbalanced distribution systems can be formulated as a mixed, non-linear, constrained optimization problem and is usually solved in deterministic scenarios. However, distribution systems are stochastic in nature, leading thus to inaccurate deterministic solutions. To take into account the unavoidable uncertainties which...
This paper presents a generalized formulation to determine the optimal operating strategy and cost optimization scheme as well as the reduction of the emissions for a MicroGrid (MG). Multiobjective (MO) optimization is applied to the environmental/economic problem of the MG. The proposed problem is formulated as a nonlinear constrained MO optimization problem. The model takes into consideration the...
This paper introduces an integration of particle swarm optimization "PSO" and successive linear programming "SLP" for dealing with VAR ancillary service problem in a competitive market-based environment. The main target of the developed market is to enable transmission operator "TO" to procure VAR service in a minimum payment while maintaining the system security in normal...
Modelling cellular dynamics based on experimental data is at the heart of system biology. Considerable progress has been made to dynamic pathway modelling as well as the related parameter estimation. However, few of them gives consideration for the issue of optimal sampling time selection for parameter estimation. Time course experiments in molecular biology rarely produce large and accurate data...
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