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991.
MATLAB r2006(7.3)下利用COM组件实现VB.net与MATLAB混合编程的新方法。并用实例介绍了这种方法的具体应用过程。 相似文献
992.
潘罡 《数字社区&智能家居》2008,(6):1318-1319
首先说明了当前江苏省电力系统中各厂家终端产品所采用的通讯规约不完全相同现状。接着分析了规约插件的设计规范和需要满足的设计需求,最后设计出解决通讯规约兼容问题的规约插件管理器。该管理器实现对所有规约插件的管理.同时实现和市场中各种电力终端设备数据通讯。 相似文献
993.
Biaosong Chen Gang Liu Jian Kang Yunpeng Li 《Structural and Multidisciplinary Optimization》2008,36(1):83-92
Stiffened storage tank is an important structural component in spacecraft. Its structural weight is one of the key criterions
in the design phase. This paper focuses on the design optimization of the structure by using finite element method, structural
sensitivity analysis techniques, and sequential linear/quadratic programming aimed to reduce the structural weight. Design
variables include the numbers of stiffeners, stiffeners’ section dimensions, and shell thickness distribution. Detailed finite
element modeling processes are presented, which are the ways to construct the stiffener (beam orientation and offset) and
shell elements and the ways to determine the analysis model and structural boundary conditions. A brief introduction to sensitivity
analysis and optimization solution algorithm is also given. Main attention is paid to the studies of design optimization of
the tank structure, including the selection of design cases, evaluation, and comparison of the optimal results. There are
six design cases considered in the design procedures. Numerical results show that by using the above computational techniques,
the structural weight is effectively reduced. In this work, MSC.Patran/Nastran is employed to construct the Finite Element
Model (FEM), and JIFEX, which is developed in our group, is used to conduct the structural design optimization.
JIFEX is a structural analysis and optimization software package developed by Gu and colleagues in the Dalian University of
Technology Department of Engineering Mechanics. Among its many functions is the ability to analyze and optimize piezoelectric
smart structures. 相似文献
994.
Shih Hao Huang Hwa Seng Khoo Shang Yu ChangChien Fan Gang Tseng 《Microfluidics and nanofluidics》2008,5(4):459-468
Monodisperse copolymer particles carrying surface carboxyl groups in the range of 50–200 μm were prepared by in situ UV polymerization
of ethyleneglycol dimethacrylate (EGDMA) with acrylic acid (AA) via a microfluidic flow-focusing device (MFFD). The design
of the coaxial orifices in the MFFD enables the confinement of the comonomer liquid thread to the central axis of the microchannel,
which can avoid the wetting problem of comonomer liquid with the microchannel and can successfully produce monodisperse copolymer
microspheres with coefficient of variance below 5%. The effects of concentration of EGDMA and AA on droplet diameters and
the distribution of carboxyl group on particle surfaces were examined. It has been found that, increasing the concentration
of AA would decrease particle sizes, but increase the distribution of carboxyl group on particle surfaces. Bioconjugation
of the carboxylated copolymer particles with the anti-rabbit IgG–Cy3 conjugates was successfully demonstrated. By increasing
the concentration of AA accompanied with decreasing the particle sizes, high efficiency of bioconjugation on carboxylated
copolymer particles was achieved. The rapid continuous synthesis of carboxylated copolymer particles via a microfluidic device
provides a reliable control of particle sizes and composition for massive production in biotechnological applications. 相似文献
995.
就某矿业集团煤矿瓦斯监管系统通信子系统应具有的功能,文章提出了一种实现方案,描述了通信子系统的组成结构及功能实现流程,分析和制定了通信协议。该通信子系统采用VB设计,利用双向通信方式和数据帧的数据格式以及定时探测的方式,有效地提高了通信系统的性能,为煤矿瓦斯监管系统提供了一个高效可靠的通信平台。 相似文献
996.
A new fault detection and diagnosis approach is developed in this paper for a class of singular nonlinear systems via the use of adaptive updating rules. Both detection and diagnostic observers are established, where Lyapunov stability theory is used to obtain the required adaptive tuning rules for the estimation of the process faults. This has led to stable observation error systems for both fault detection and diagnosis. A simulated numerical example is included to demonstrate the use of the proposed approach and encouraging results have been obtained. 相似文献
997.
In this paper, we present an interval model of networked control systems with time-varying sampling periods and time-varying network-induced delays and discuss the problem of stability of networked control systems using Lyapunov stability theory. A sufficient stability condition is obtained by solving a set of linear matrix inequalities. In the end, the illustrative example demonstrates the correctness and effectiveness of the proposed approach. 相似文献
998.
本文针对产品设计中的"软设计"理念进行诠释和探讨。笔者认为随着社会的发展,科技的进步,设计文化在产品中的渗透,"软设计"理念在产品设计过程中凸显重要。 相似文献
999.
通过分析当今设计领域的伦理缺失现象,从道德层面对由设计带来的金钱至上、道德沦丧、环境污染和资源浪费等问题进行批判,并提出设计要实现以人的关怀为基准的伦理回归。 相似文献
1000.
在网络上传播的数码图形艺术与计算机和网络有着密不可分的关系,它立足于网络交互性和数码造像的特质,带有强烈的数字艺术的特征,也形成了自己特有的时代特征。 相似文献