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61.
阐述了铜杆生产过程中信息采集系统的主要研究内容;概括了硬件的结构和选用的主要设备;阐述了上位机软件的主要模块及实现方法;系统采用面向对象的编程方法,界面友好,操作简单,功能完善;实际运行效果良好,具有较好的应用前景。 相似文献
62.
I. N. Ishchuk 《Measurement Techniques》2007,50(10):1081-1086
A three-dimensional solution of the direct problem of heat conduction when a linear pulsed heat source acts in the plane of
contact of two semibounded bodies is presented. The solution is obtained by the method of finite differences. An example of
the modeling is considered.
__________
Translated from Izmeritel’naya Tekhnika, No. 10, pp. 42–45, October, 2007. 相似文献
63.
Zden k Slanina Filip Uhlí k Ludwik Adamowicz 《Fullerenes, Nanotubes and Carbon Nanostructures》2003,11(3):219-226
C60F48 has been known to exist in two isomeric forms of D3 and S6 symmetries. However, the quantum-chemical calculations have not agreed on their stability order though a near-isoenergetic picture is otherwise always encountered. In order to clarify the situation, the entropy effects are evaluated for synthetic temperatures of about 500K. The entropy evaluations suggest that the D3 isomer should be more stable in the potential energy by 2.05-2.55 kcal/mol (to which term the ab initio data are closer than the semiempirical ones). 相似文献
64.
双自由度后坐保险机构的计算机动态仿真 总被引:5,自引:2,他引:3
在Workin Model 3D软件上对引信的双自由度后坐保险机构进行了有关计算机仿真计算,并结合具体实例进行了优化设计。 相似文献
65.
基于闭路电视网络的计算机远程控制 总被引:1,自引:1,他引:0
介绍了一种在闭路电视网络上利用DTMF变换技术和调频技术相结合来传输计算机串行控制编码信号的方法,并且将这种控制方法应用到计算机远程广播控制系统中。 相似文献
66.
Finite element analyses (FEA) of thermosets are often performed on the basis of rheological data for fully cured resin. For the FEA of thermosets during curing, a material model is established and a technique is demonstrated, which allows the rheological data of the linear viscoelastic material to be derived. As the moduli are sensitive to conversion, all measured properties are related to temperature and conversion. Therefore the basis for the rheological data has to be a suitable reaction kinetic. Based on the kinetics shear and compression properties are measured independently and modeled mathematically with the focus to gain a formulation, which is suitable for FEA. The considered time constants are in the range between one second and one month as these times are relevant for the investigated relaxation times. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1868–1872, 2003 相似文献
67.
FLOW OF NEWTONIAN FLUIDS THROUGH SINUSOID ALLY CONSTRICTED TUBES. NUMERICAL AND EXPERIMENTAL RESULTS
J. A. Deiber Mb. Peirotti R. A. Bortolozzi R. J. Durelli 《Chemical Engineering Communications》1992,117(1):241-262
Numerical and experimental predictions of pressure drops in the flow of Newtonian fluids through sinusoidally constricted tubes (SCT) are carried out. The numerical evaluations analyzed in this work are obtained from the following methods: Geometric Iteration (GJM), Geometric Iteration with First and Second Upwinds (GIM1, GIM2), Successive Over Relaxation by Line (SORBLM), Global Galerkin Spectral Method (GGSM), Collocation (CM) and Dufort-Frankel (DFM). The GIM1, GIM2 and SORBLM are applied to SCT and explained in this work. The other methods have been previously reported in the literature with the same purpose. Experiments are accomplished for constrictions of approximately 40,60 and 80% of the average tube diameter and results compare well with numerical predictions of the steady flow. It is concluded that special attention should be given to evaluations of the friction factor ƒ for Reynolds numbers Re between the onsets of flow separation and turbulence due to flow instability. Finally, the SCT as a model for porous media (PM) is discussed. 相似文献
68.
Data fitting with a spline using a real-coded genetic algorithm 总被引:2,自引:0,他引:2
Fujiichi Yoshimoto Author Vitae Toshinobu Harada Author Vitae Author Vitae 《Computer aided design》2003,35(8):751-760
To obtain a good approximation for data fitting with a spline, frequently we have to deal with knots as variables. The problem to be solved then becomes a continuous nonlinear and multivariate optimization problem with many local optima. Therefore, it is difficult to obtain the global optimum. In this paper, we propose a method for solving this problem by using a real-coded genetic algorithm. Our method can treat not only data with a smooth underlying function, but also data with an underlying function having discontinuous points and/or cusps. We search for the best model among candidate models by using the Bayes Information Criterion (BIC). With this, we can appropriately determine the number and locations of knots automatically and simultaneously. Five examples of data fitting are given to show the performance of our method. 相似文献
69.
计算机应用技术伴随着行业工程技术的发展同步开发。它已广泛应用于建筑工程中。从三个方面分析了计算机在建筑工程中的应用问题:1)在建筑物可靠鉴定领域、工程设计、管理中的应用;2)不足:包括计算机软件的开发受限制,已开发软件的局限性,已有档案资料复用技术水平低,缺乏资料共享、信息库支援;3)发展方向:建立强大信息库,开发全面应用系统,日常使用管理系统,典型问题治理专家系统。并提出未来发展重点-信息库(共享)机制。 相似文献
70.
生产装置在线模拟与优化技术的应用 总被引:5,自引:0,他引:5
概述了以通用软件为基础开发化工生产装置严格在线模拟与优化系统的过程,介绍了在线模型的5个层次及其特点,以合成氨为例说明了在线模型的运行和应用情况。 相似文献