The shielding performance of perforated magnetic shields for electric power applications is described. The shielding of an axisymmetric induction heating device is studied as a function of frequency, number of perfora...
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The shielding performance of perforated magnetic shields for electric power applications is described. The shielding of an axisymmetric induction heating device is studied as a function of frequency, number of perforations and dimensions of the perforations. From the numerical point of view, the perforations cause the numerical model to be 3D. A numerical optimisation is carried out to find the optimal geometry with respect to the shielding factor and the volume of the shield. For the optimisation, two approaches are presented. The first approach is fast and easy-to-implement, but has limited accuracy. It uses a classical 2D axisymmetric model where the perforations are approximated by 'axisymmetric air gaps' resulting in a segmented shield. It is shown how to modify the 2D model to obtain results that are similar to the ones of a 3D model. The second approach is more accurate although quite fast, but more difficult to implement. It combines a 3D thin-shell finite element model with the unmodified 2D model in a space mapping optimisation algorithm. The validation of both models is based on experimental work for an unperforated shield and for the optimised perforated shield.
This paper considers a model for locating a consumer within a bounded region in the plane with respect to a set of n existing pull-push suppliers. The objective is to maximize the difference of total profits and costs...
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This paper considers a model for locating a consumer within a bounded region in the plane with respect to a set of n existing pull-push suppliers. The objective is to maximize the difference of total profits and costs incurred due to the partial covering of the consumer by the suppliers pull and push influence areas. We develop efficient polynomial time algorithms for the resulting problems in the rectilinear and the Euclidean planes where the bounded region is either a rectangle or a constant size polygon, respectively. Based on these solutions, we develop algorithms for evaluating efficiently the objective function at any possible location of the consumer inside the bounded region. We also employ the algorithms for the Euclidean optimization problem and the rectilinear query computation to solve efficiently their corresponding dynamic versions. where an appearance of a new supplier or an absence of an existing one occurs. Being easy to implement due to the extensive use of simple data structures, such as the balanced and binary segment tree, and the employment of standard mechanisms, such as the sweep line, the Voronoi diagram and the circular ray shooting, our solutions potentially have wide usability. (C) 2008 Elsevier B.V. All rights reserved.
The present state of the IT industry is characterized by a large variety of computing systems. An optimizing compiler is the main tool for the efficient use of the hardware capabilities of such systems. The main purpo...
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The present state of the IT industry is characterized by a large variety of computing systems. An optimizing compiler is the main tool for the efficient use of the hardware capabilities of such systems. The main purpose of optimizing compiler is to obtain a code that is the most efficient for the given computing system. A modern optimizing compiler is a software tool used to compile a program developed in some input programming language (C, C++, Fortran, etc.) or represented in machine code (x86, SPARC, etc.) into some output language or machine code. In the process of compilation, the program is sequentially transformed into intermediate representations used to retain the program semantics. Analysis and optimization algorithms are implemented at the interfaces between the intermediate representations.
In this paper, the problem of determining the optimum number and locations of banking automatic teller machines (ATMs) is considered. The objective is to minimize the total number of ATMs to cover all customer demands...
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In this paper, the problem of determining the optimum number and locations of banking automatic teller machines (ATMs) is considered. The objective is to minimize the total number of ATMs to cover all customer demands within a given geographical area. First, a mathematical model of this optimization problem is formulated. A novel heuristic algorithm with unique features is then developed to efficiently solve this problem. Finally, simulation results show the effectiveness of this algorithm in solving the ATM placement problem. (C) 2009 Elsevier Ltd. All rights reserved.
This article first analyses the reason that A* algorithm influences speed when searching for optimum route in game map, then it gives the optimization scheme from the aspects of node structure, the maintenance of open...
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ISBN:
(纸本)9780791802977
This article first analyses the reason that A* algorithm influences speed when searching for optimum route in game map, then it gives the optimization scheme from the aspects of node structure, the maintenance of open queue and so on. What is more, it carries out theoretical analysis for the improvable A* algorithm. At the same time, the scheme is tested and evaluated by a lot of different big and small maps. Experiment result shows the improvable A* has very actual value in seeking the solution of way problem for map. And it has certain reference meaning in instant strategic kinds of game.
A hierarchical optimisation strategy has been introduced for minimising the Hartree-Fock/Kohn-Sham energy, consisting of three levels (3L): an atom-in-a-molecule optimisation, a valence-basis molecular optimisation, a...
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A hierarchical optimisation strategy has been introduced for minimising the Hartree-Fock/Kohn-Sham energy, consisting of three levels (3L): an atom-in-a-molecule optimisation, a valence-basis molecular optimisation, and a full-basis molecular optimisation. The density matrix formed at one level is used as a starting density matrix at the next level with no loss of information. To ensure a fast and reliable convergence to a minimum, the augmented Roothaan-Hall (ARH) algorithm is used in both the valence-basis and full-basis molecular optimisations. The performance of the ARH-3L method is compared with standard optimisation algorithms. Both for efficiency and reliability, we recommend to use the ARH-3L algorithm.
Constructing physiologically relevant compartmental models of neurones is critical for understanding neuronal activity and function. We recently suggested that measurements from multiple locations along the soma, dend...
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Constructing physiologically relevant compartmental models of neurones is critical for understanding neuronal activity and function. We recently suggested that measurements from multiple locations along the soma, dendrites and axon are necessary as a data set when using a genetic optimization algorithm to constrain the parameters of a compartmental model of an entire neurone. However, recordings from L5 pyramidal neurones can routinely be performed simultaneously from only two locations. Now we show that a data set recorded from the soma and apical dendrite combined with a parameter peeling procedure is sufficient to constrain a compartmental model for the apical dendrite of L5 pyramidal neurones. The peeling procedure was tested on several compartmental models showing that it avoids local minima in parameter space. Based on the requirements of this analysis procedure, we designed and performed simultaneous whole-cell recordings from the soma and apical dendrite of rat L5 pyramidal neurones. The data set obtained from these recordings allowed constraining a simplified compartmental model for the apical dendrite of L5 pyramidal neurones containing four voltage-gated conductances. In agreement with experimental findings, the optimized model predicts that the conductance density gradients of voltage-gated K+ conductances taper rapidly proximal to the soma, while the density gradient of the voltage-gated Na+ conductance tapers slowly along the apical dendrite. The model reproduced the back-propagation of the action potential and the modulation of the resting membrane potential along the apical dendrite. Furthermore, the optimized model provided a mechanistic explanation for the back-propagation of the action potential into the apical dendrite and the generation of dendritic Na+ spikes.
Numerical simulation is an invaluable tool for the designer of any device. By providing a model of the sensor within the design parameters, simulation can substantially speed up and simplify the design process and giv...
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Data about some genetic factors of male infertility are presented, and methods, which may be used for its diagnosing, are studied. Among genetic factors the following are distinguished: changes in the level of genes (...
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Data about some genetic factors of male infertility are presented, and methods, which may be used for its diagnosing, are studied. Among genetic factors the following are distinguished: changes in the level of genes (mutations), chromosomes (chromosomal aberrations), and total DNA (chromatin dispersion and DNA fragmentation). As well as standard cytogenetic methods of investigation there are a number of molecular-cytogenetic methods like FISH (fluorescent in situ hybridization), TUNEL (Terminal uridine deoxynucleotidyl transferase dUTP nick end labeling), SCSA (sperm chromatin structural assay), SCGE (single cell gel electrophoresis), and SCD (sperm chromatin dispersion). The thorough study of the sperm of infertile men on several levels of organization let us assess the informativity of each method separately and together, and also develop an optimal algorithm of diagnostics with the aim to choose further tactics in the treatment of male infertility.
The paper presents the ALADIN prototype for adaptive lighting control designed to assist elderly in achieving a state of well-being, developed as a FP6 EU funded project. It uses psycho-physiological features extracte...
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ISBN:
(纸本)9783642027307
The paper presents the ALADIN prototype for adaptive lighting control designed to assist elderly in achieving a state of well-being, developed as a FP6 EU funded project. It uses psycho-physiological features extracted from Electro-Dermal Activity (EDA) and Pulse signals to determine the subject's mental state and adapts the lighting parameters in order to achieve a certain desired state. One of the controller implementations was done using Simulated Annealing. Field test evaluations of this implementation are discussed.
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