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971.
The recently developed high-order accurate multiple image approximation to the reaction field for a charge inside a dielectric sphere [J. Comput. Phys. 223 (2007) 846-864] is compared favorably to other commonly employed reaction field schemes. These methods are of particular interest because they are useful in the study of biological macromolecules by the Monte Carlo and Molecular Dynamics methods. 相似文献
972.
Parallelization of the global extremum searching process 总被引:1,自引:0,他引:1
Yu. G. Evtushenko V. U. Malkova A. A. Stanevichyus 《Automation and Remote Control》2007,68(5):787-798
The parallel algorithm for searching the global extremum of the function of several variables is designed. The algorithm is based on the method of nonuniform coverings proposed by Yu.G. Evtushenko for functions that comply with the Lipschitz condition. The algorithm is realized in the language C and message passing interface (MPI) system. To speed up computations, auxiliary procedures for founding the local extremum are used. The operation of the algorithm is illustrated by the example of atomic cluster structure calculations. 相似文献
973.
Songhua Xu Haisheng Tan Xiantao Jiao Francis C.M. Lau Yunhe Pan 《Computer Graphics Forum》2007,26(3):609-618
We propose a generic pigment model suitable for digital painting in a wide range of genres including traditional Chinese painting and water-based painting. The model embodies a simulation of the pigment-water solution and its interaction with the brush and the paper at the level of pigment particles; such a level of detail is needed for achieving highly intricate effects by the artist. The simulation covers pigment diffusion and sorption processes at the paper surface, and aspects of pigment particle deposition on the paper. We follow rules and formulations from quantitative studies of adsorption and diffusion processes in surface chemistry and the textile industry. The result is a pigment model that spans a continuum from the very wet to the very dry brush stroke effects. We also propose a new pigment mixing method based on machine learning techniques to emulate pigment mixing in real life as well as to support the creation of new artificial pigments. To experiment with the proposed model, we embedded the model in a sophisticated digital brush system. The combined system exhibits interactive speed on a modest PC platform. http://www.cs.hku.hk/~songhua/pigment provides supplementary materials for this paper. 相似文献
974.
The results of processing the experimental drain-gate characteristics of test MOS transistors after irradiation with fast electrons and subsequent heat treatment are reported. It is shown that the concentration of trapping centers in the oxide is lowered as a result of radiation-thermal treatment. 相似文献
975.
G. Sh. Tsitsiashvili 《Automation and Remote Control》2007,68(7):1177-1185
Consideration was given to the parametric and structural optimization of the throughput of various queuing systems. Solutions of these problems rely on a combination of the decomposition methods for optimization of the nonsmooth functions and search of the admissible solutions of the transportation problem, as well as on the majorant estimates of the efficiency of the integrated queuing systems. 相似文献
976.
Stability-optimal solutions were established for the problem of control of the aperiodic, delay, and oscillatory plants approximated by the dynamic models representing a serial connection of the inertial units, inertial delay unit, and inertial units with oscillatory unit. 相似文献
977.
Real-time homogenous translucent material editing 总被引:4,自引:0,他引:4
This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates. 相似文献
978.
No authorship indicated 《Canadian Metallurgical Quarterly》2006,61(8):757
Presents the citation to Marcia K. Johnson, who received the Award for Distinguished Scientific Contributions "for raising and illuminating fundamental questions about the cognitive and neural processes that constitute the subjective experience of mental life." A brief profile and a selected bibliography, as well as Johnson's award address, entitled Memory and Reality (see record 2006-21079-028), accompany the citation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
979.
现代水环境监测系统是一个具有现代高性能、多层次的复杂系统,这要求多个(种、异质)传感器在不同尺度上对水环境进行观测。探讨和分析了信息融合技术应用于水环境监测的特点,提出了一种运用专家系统和黑板理论的水环境监测信息融合结构框架。 相似文献
980.
在研究数据库技术在大坝安全监测系统中的应用的基础上,开发了卧虎山水库大坝安全监测系统。以Delphi和SQL Server 2000为开发环境,详细介绍了系统的数据库结构设计、数据库接口设计以及ADO和ADO.NET在系统中的应用和作用。 相似文献