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51.
以大型半导体制造企业为应用背景,应用在线设备监测系统TFM,对生产中心的生产设备运作信息进行实时集成和同步反馈,实现设备运行状态数据的显示、设备维护计划的查询和决策、设备生产效率的比较分析。把反映生产设备运行状态的动态数据提炼为形象直观的分析图形,实现可视化信息管理,提高生产中心现场设备管理水平。 相似文献
52.
High temperature solid oxide fuel cell (SOFC) has prospect and potential to generate electricity from fossil fuels with high efficiency and very low greenhouse gas emissions as compared to traditional thermal power plants. In the last 10 years, there has been significant progress in the materials development and stack technologies in SOFC. The objective of this paper is to review the development of anode materials in SOFC from the viewpoint of materials microstructure and performance associated with the fabrication and optimization processes. Latest development and achievement in the Ni/Y2O3-ZrO2 (Ni/YSZ) cermet anodes, alternative and conducting oxide anodes and anode-supported substrate materials are presented. Challenges and research trends based on the fundamental understanding of the materials science and engineering for the anode development for the commercially viable SOFC technologies are discussed. 相似文献
53.
The orthogonal neural network is a recently developed neural network based on the properties of orthogonal functions. It can avoid the drawbacks of traditional feedforward neural networks such as initial values of weights, number of processing elements, and slow convergence speed. Nevertheless, it needs many processing elements if a small training error is desired. Therefore, numerous data sets are required to train the orthogonal neural network. In the article, a least‐squares method is proposed to determine the exact weights by applying limited data sets. By using the Lagrange interpolation method, the desired data sets required to solve for the exact weights can be calculated. An experiment in approximating typical continuous and discrete functions is given. The Chebyshev polynomial is chosen to generate the processing elements of the orthogonal neural network. The experimental results show that the numerical method in determining the weights gives as good performance in approximation error as the known training method and the former has less convergence time. © 2004 Wiley Periodicals, Inc. Int J Int Syst 19: 1257–1275, 2004. 相似文献
54.
The discretized quadratic sub‐optimal tracker for nonlinear continuous two‐dimensional (2‐D) systems is newly proposed in this paper. The proposed method provides a novel methodology for indirect digital redesign for nonlinear continuous 2‐D systems with a continuous performance index. This includes the following features: (1) the 2‐D optimal‐linearization approach of the nonlinear 2‐D Roesser's model (RM), (2) the dynamic programming‐based discretized quadratic optimal tracker for linear continuous 2‐D systems, (3) the steady‐state discretized quadratic sub‐optimal tracker for linear continuous 2‐D systems, and (4) the discretized quadratic sub‐optimal tracker for nonlinear continuous 2‐D systems. Illustrative examples are presented to demonstrate the effectiveness of the proposed procedure. 相似文献
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A. Mendizabal J. B. González-Díaz M. San Sebastián A. Echeverría 《Journal of Materials Engineering and Performance》2016,25(7):2670-2678
This paper describes the implementation of a simple strategy adopted for the inherent shrinkage method (ISM) to predict welding-induced distortion. This strategy not only makes it possible for the ISM to reach accuracy levels similar to the detailed transient analysis method (considered the most reliable technique for calculating welding distortion) but also significantly reduces the time required for these types of calculations. This strategy is based on the sequential activation of welding blocks to account for welding direction and transient movement of the heat source. As a result, a significant improvement in distortion prediction is achieved. This is demonstrated by experimentally measuring and numerically analyzing distortions in two case studies: a vane segment subassembly of an aero-engine, represented with 3D-solid elements, and a car body component, represented with 3D-shell elements. The proposed strategy proves to be a good alternative for quickly estimating the correct behaviors of large welded components and may have important practical applications in the manufacturing industry. 相似文献
57.
H. Hoseiny F. G. Caballero B. Högman D. San Martin C. Capdevila L. -G. Nordh H. -O. Andrén 《Journal of Materials Science》2012,47(8):3613-3620
The effect of martensitic packet size on the machinability of prehardened mold steel at a hardness of ~40 HRC (typical hardness
for prehardened mold steels) was studied in terms of cutting force and tool life. The machinability tests were performed in
end milling using coated, cemented carbide tools at three different cutting speeds. The results showed that an increase in
the martensite packet size led to higher cutting force and shorter tool life. The increase in cutting force was related to
the increase of work hardening. The work material with a coarser martensite packet size showed a higher amount of work hardening
that can explain the higher cutting force. The longer tool life in the workpieces with finer structure was correlated to smaller
amplitude of the variation in cutting force. 相似文献
58.
Chin‐San Wu 《Polymer International》2012,61(10):1556-1563
Poly(butylene adipate‐co‐terephthalate) (PBAT) composites containing polyaniline (PANI) were prepared using a melt blending process. Acrylic‐acid‐grafted PBAT (PBAT‐g‐AA) and PANI were used to improve the compatibility and dispersibility of PANI within the PBAT matrix. The composites were characterised morphologically using scanning electron microscopy, chemically using Fourier transform IR spectrometry and 13C solid‐state nuclear magnetic resonance, and optically using UV‐visible spectroscopy. The electrical conductivity of the composites was also evaluated with a resistance tester and a cyclic voltameter. Escherichia coli (BCRC 10239) was chosen as the standard bacterium for determining the antibacterial properties of the composite materials. The anti‐static properties of the composites were also evaluated. The PBAT‐g‐AA/PANI composite showed markedly enhanced antibacterial and anti‐static properties due to the formation of amide bonds by the condensation of the carboxylic acid groups of PBAT‐g‐AA with the amino groups of PANI. The optimal level of PANI was 9 wt%, as excess PANI led to separation of the two organic phases, lowering their compatibility. Copyright © 2012 Society of Chemical Industry 相似文献
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