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51.
52.
A new analytical method called He’s variational iteration method (VIM) is introduced to be applied to solve nonlinear Benjamin-Bona-Mahony-Burgers
(BBMB) equations and free vibration of a nonlinear system having combined linear and nonlinear springs in series in this article.
In this method, general Lagrange multipliers are introduced to construct correction functionals for the problems. The multipliers
can be identified optimally via the variational theory. The results are compared with the results of the homotopy analysis
method and also with the exact solution. He’s Variational iteration method in this problem functions so better than the homotopy
analysis method and exact solutions one of them in per section. 相似文献
53.
Yves Sprumont 《International Journal of Game Theory》2008,37(2):155-184
A group of agents participate in a cooperative enterprise producing a single good. Each participant contributes a particular type of input; output is nondecreasing in the input profile. How should it be shared? We analyze the implications of the axiom of Group Monotonicity: if a group of agents simultaneously decrease their input, not all of them should receive a bigger share of output. We show that in combination with other more familiar axioms, this condition pins down a very small class of methods, which we dub nearly serial. 相似文献
54.
通过一定的软硬件设计,提出了一种将现有的多台独立微机线路保护实验台借助Visual Basic平台与计算机联网的方法.在所编制监控软件环境下,充分运用计算机的数据处理和数据存储能力,实现了继电保护室的网络化和四遥功能,在继电保护整定计算等电力系统软件与实验装置问构建了桥梁,把实验室模拟成变电站自动化实时控制系统现场. 相似文献
55.
Michal Penn 《Discrete Applied Mathematics》2008,156(4):412-419
We study unreliable serial production lines with known failure probabilities for each operation. Such a production line consists of a series of stations; existing machines and optional quality control stations (QCS). Our aim is to simultaneously decide where and if to install the QCSs along the line and to determine the production rate, so as to maximize the steady state expected net profit per time unit from the system.We use dynamic programming to solve the cost minimization auxiliary problem where the aim is to minimize the time unit production cost for a given production rate. Using the above developed O(N2) dynamic programming algorithm as a subroutine, where N stands for the number of machines in the line, we present an O(N4) algorithm to solve the Profit Maximization QCS Configuration Problem. 相似文献
56.
串口通讯在工业领域有着重要的作用。VC在工业中经常被使用制作各种复杂的监控控制软件,但是VC的图形绘制、API接口功能等存在不方便的地方,本文使用VC的处理能力并借用Qt的图形和其它API接口,这样会大大增加软件开发效率,同时所做软件可移植性变强,可以使用在不同的操作系统中。脉冲发生器在工业系统中运行较多,本文以脉冲发生器为下位机和PC端进行串口通讯的方法。由于工业级软件的设计、应用目前大部分仍以Windows XP为主,所以本文介绍方法主要解决了在低电脑配置PC、低操作系统下灵活使用VC6.0嵌套QT3.3创作出界面强大、稳定的上位机软件。 相似文献
57.
Dugo P Herrero M Giuffrida D Ragonese C Dugo G Mondello L 《Journal of separation science》2008,31(12):2151-2160
In the present contribution, a novel analytical approach based on using serial coupled conventional LC columns is proposed to the study of the native carotenoid composition of orange juice. The great difficulties that are found when analyzing complex carotenoid samples, due to the high natural variability of these compounds as well as to the presence of carotenoid esters are well documented. To overcome some of these limitations, we have developed a methodology including the study of both the saponified and the intact sample by means of two different LC-DAD/APCI-MS methods. The increase in the resolution and separation power obtained when using two serial coupled C(30) columns is demonstrated, and significant increases in peak capacity have been achieved. By using this new methodology, 44 different carotenoids have been tentatively identified. Among them, several violaxanthin diesters have been directly identified in orange juice for the first time. The main carotenoids in orange juice were violaxanthin, lutein, luteoxanthin, 9-cis-antheraxanthin, and beta-cryptoxanthin. Some of them were found in both their free and esterified forms. To the best of our knowledge, this is the first application of serial couplings of C(30) columns for the identification of the native carotenoid composition of natural matrices. 相似文献
58.
Summary There are a number of parameters which have to be chosen depending on the analysis being done in gas chromatography. While the choice of stationary phase material is based on the solutes to be separated, the thickness is dependent on the concentration and the volatility of the components to be analyzed. This study undertakes a coupled column phase ratio optimization by connecting a short piece of a particular column prior to a normal length of an analytical column. Various columns of different dimensions (phase ratio), but of the same stationary phase material (methyl silicone), are coupled together by a deactivated glass press-fit connector, and the efficiency and capacity are measured. The coupling of fused silica open tubular columns is optimized in efficiency by matching or decreasing the phase ratio of successive columns. Capacity optimization is accomplished by increasing the phase ratio of consecutive columns. Capacity and efficiency optimization are opposing each other; therefore, if some efficiency can be sacrificed a substantial increase in capacity is possible. 相似文献
59.
为了满足新的信号处理平台使用RapidIO技术来进行重构的要求,实现DSP芯片在信号处理板之间和机箱之间的动态连接配置,提出了一种基于RapidIO的网络交换板卡的设计和实现方式。板卡使用TSI578交换芯片构成RapidIO交换机,来实现信号处理板和网络交换板之间的RapidIO数据包路由交换;使用千兆以太网和光纤来实现机箱间的互连;使用FPGA芯片来实现RapidIO和千兆以太网、光纤数据之间的协议转换。应用结果表明,利用该网络交换板能够很好的实现DSP芯片在板卡间与机箱间的互连重构。 相似文献
60.
Frederick T. Simon 《Analytica chimica acta》1999,380(2-3):417-423
A method has been developed to obtain the reflective spectral data, βR(λ), for a fluorescent sample by making a simple modification to a conventional poly-chromatically illuminated spectrophotometer. To use this procedure, a series of sharp cut-off filters are inserted successively into the illumination beam of the instrument to obtain a number of spectral curves from which the complete reflectance curve is constructed piece-wise. The calculation of the complete reflectance curve is done wavelength-by-wavelength, starting at about 30 nm above the peak emission of the sample and proceeding toward the shortest wavelength cut-off filter, selecting the spectral data that are the lowest value. When the data from each filter are assembled, the long wavelength portion above the peak emission is made equal to the unmodified spectrum. Examples are given of the method of computation and comparison with bi-spectral data. The serial filter technique is equally applicable to instruments having either 45/0 or d/8 integrating sphere optical geometry. 相似文献