the paper describes an investigation about the application of the new multiple-impedance discontinuities model for optimizing profile diffuser barriers. the new multiple-impedance discontinuities model is much faster than the numerical method, thus it is used in an optimization process. the a-weighted insertion loss was used for the traffic noise spectrum. the result of optimization, which is d...

A heuristic particle swarm optimization (PSO) based algorithm is presented in this work and the novel hybrid approach is applied to linear array synthesis considering complex weights and directive element patterns so as to analyze its usefulness and limitations. Basically, classical PSO schemes are modified by introducing a tournament selection strategy and the downhill simplex local search met...

Let the least value of the function F (x), x∈Rn, be required, where n ≥ 2. If the gradient ∇F is available, then one can tell whether search directions are downhill, and first order conditions help to identify the solution. It seems in practice, however, that the vast majority of unconstrained calculations do not employ any derivatives. A view of this situation is given, attention being restric...

The asymmetric time dependence and various statistical properties of polarity reversals of the Earth’s magnetic field are utilized to infer some of the most essential parameters of the geodynamo, among them the effective (turbulent) magnetic diffusivity, the degree of supercriticality, and the relative strength of the periodic forcing which is believed to result from the Milankovic cycle of the...

The augmented predecessor Indexing method is a procedure for efficiently updating the basis representation, flows and node potentials in an adjacent extreme point (or "simplex" type) method for network problems, utilizing ideas due to Ellis Johnson in his proposed application of a triple-label representation to networks. The procedure is extended here to accommodate the more complex basis struc...

The Shuffled Complex Evolution (SCE-UA) has been used extensively and proved to be a robust and efficient global optimization method for the calibration of conceptual models. In this paper, we propose two enhancements to the SCE-UA algorithm, one to improve its exploration and another to improve its exploitation capability of the search space. A strategically located initial population is used ...

This work deals with the application of metaheuristics to the fuel consumption minimization problem of hybrid electric vehicles (HEV) considering exactly specified driving cycles. A genetic algorithm, a downhill-simplex method and an algorithm based on swarm intelligence are used to find appropriate parameter values aiming at fuel consumption minimization. Finally, the individual metaheuristics...

Detection of the best symmetry plane in 3D images can be treated as a registration problem between the original and the reflected images. The registration is performed in a 3D space of parameters defining orientation and shift of a reflection plane. We use the normalized metric as the similarity measure between original and reflected images and investigate an algorithm for computation of the be...

A simple real-time beam tuning program has been developed for use at the KEK B-Factory injector linac. The program features the ability to adjust an arbitrary combination of parameters (e.g. magnet currents and RF phases) in order to optimize an arbitrary combination of monitor values (e.g. the ratio of a downstream beam current to gun current). Based on the downhill-simplex method[2][?], it re...