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Assen, Netherlands

Gholaminezhad I.,Guilan University | Iacca G.,INCAS
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

This paper describes a new evolutionary algorithm for multiobjective optimization, namely Multi-Objective Relative Clustering Genetic Algorithm (MO-RCGA), inspired by concepts borrowed from gene relatedness and kin selection theory. The proposed algorithm clusters the population into different families based on individual kinship, and adaptively chooses suitable individuals for reproduction. The idea is to use the information on the position of the individuals in the search space provided by such clustering schema to enhance the convergence rate of the algorithm, as well as improve its exploration. The proposed algorithm is tested on ten unconstrained benchmark functions proposed for the special session and competition on multi-objective optimizers held at IEEE CEC 2009. The Inverted Generational Distance (IGD) is used to assess the performance of the proposed algorithm, in comparison with the IGD obtained by state-of-the-art algorithms on the same benchmark. © Springer-Verlag Berlin Heidelberg 2014.

Zaharovits A.,Polytechnic University of Bucharest | Stegaru S.,Polytechnic University of Bucharest | Carabas M.,Polytechnic University of Bucharest | Slusanscrn E.-I.,Polytechnic University of Bucharest | Pricop M.-V.,INCAS
2015 14th RoEduNet International Conference - Networking in Education and Research, RoEduNet NER 2015 - Proceedings | Year: 2015

This paper aims to study and improve the runtime of a topology optimization scientific code named OPTRUSS (OPTimization of TRUSS structures), developed at the Romanian National Institute for Aerospace Research 'Elie Carafoli'. OPTRUSS is a FORTRAN code that optimizes the stiffness of truss structure, minimizing compliance, following the SIMP algorithm. The physical problem solved is relevant because of the linear system's assembled stiffness sparse matrix - emphasis on sparse. The primary metric for performance is the average Wall Time per iteration of the Conjugate Gradient algorithm, and we will focus on evaluating the speedup of the proposed OpenMP and CUDA parallelizations. © 2015 IEEE.

Comrie A.C.,University of Cape Town | Buffler A.,University of Cape Town | Smit F.D.,IThemba LABS | Wortche H.J.,INCAS
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2015

Three different digital implementations of pulse shape discrimination for pulses from an EJ301 liquid scintillator detector are presented, and illustrated with neutrons and gamma-rays produced by an Am-Be radioisotopic source, a D-T generator and beams produced by cyclotron-accelerated protons of energies 42, 62 and 100 MeV on a Li target. A critical comparison between the three methods is provided. © 2014 Elsevier B.V. All rights reserved.

Vasiliu G.C.,Polytechnic University of Bucharest | Vasiliu D.,Polytechnic University of Bucharest | Vasiliu N.,Polytechnic University of Bucharest | Ion Guta D.,INCAS
UPB Scientific Bulletin, Series D: Mechanical Engineering | Year: 2014

The paper presents the mathematical modeling, and the numerical simulation of the dynamics of a swashplate servopump with mechanical feedback. The servomechanism controlling the pump displacement is supplied by a low pressure gear pump, and includes oversized pistons for rejecting the high frequency tilting force. The response time is controlled by the diameter of a metering orifice sited on the supply port. The theoretical performance of the servopump is found in good agreement with the manufacturer specifications.

Hao Y.,University of Sheffield | Kang J.,University of Sheffield | Krijnders J.D.,INCAS
Landscape and Urban Planning | Year: 2015

The aim of this study is to determine how to increase birdsong loudness and the visibility of green areas in low-density residential areas by controlling urban morphological parameters. The spatial sound level distributions of birdsong at 12 sites sampled from a GIS database of Assen, the Netherlands, were simulated by noise mapping techniques and calculated using a MATLAB program on spatial sound level matrices. The visibilities of green areas are analysed and calculated by Visibility Analysis Graph in Space Syntax. Correlation analyses were conducted between the obtained data on spatial sound level indices, the mean visibility and urban morphological parameters. The results show that birdsong loudness has significant positive linear relationships with urban morphological parameters, including Building Plan Area Fraction (R2=0.491), Green Area Perimeters (R2=0.491) and Green Area Dispersion Index (R2=0.618), while the visibility of green area has negative linear relationships with morphological parameters, including Building Plan Area Fraction (R2=0.431) and Green Area Perimeters (R2=0.799). It has also been found that in the proximity of green areas, the visibility of green areas has a positive relationship with birdsong loudness, whereas in most areas further from green areas, the visibility of green areas has a negative relationship with birdsong loudness. Either increasing birdsong loudness or enhancing visibility of the green areas by controlling urban morphological parameters is helpful for the optimisation of soundscape design with masking effects. Bird habitats and vegetation are important ecological issues to consider for the enhancement of the roles of urban morphology. © 2015 Elsevier B.V.

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