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991.
Cyclic hoist scheduling in large real-life electroplating lines 总被引:3,自引:0,他引:3
This paper addresses cyclic scheduling of a single hoist in large real-life electroplating lines, where a part visits some
processing tanks more than once and multiple duplicate tanks are used at some production stages having long processing times.
We present a formal analysis of the problem and propose an efficient branch-and-bound algorithm. The developed analytical
properties allow us to considerably eliminate dominated or infeasible solutions in the branch-and-bound procedure. Computational
results on benchmark and real-life instances show that the algorithm is very efficient in scheduling large electroplating
lines. 相似文献
992.
Tubular α-FeOOH was synthesized via hydrothermal reaction at 120 °C. X-ray diffraction (XRD) pattern indicates that the as-prepared sample is the pure orthorhombic phase α-FeOOH. Fourier transform infrared (FT-IR) analysis further confirms the formation of orthorhombic phase α-FeOOH. The morphology and structure of the as-obtained product were characterized by transmission electron microscopy (TEM) techniques. TEM images show a high degree of contrast between the bright central part and the darker edges, demonstrating the hollow core of the product. The obtained tubular α-FeOOH was ∼ 10 nm in outer diameter and ∼ 6 nm in inner diameter, respectively. High-resolution TEM image of one single nanotube shows the clearly resolved interplanar spacing of about 4.18 Å, which corresponds to the spacing between (110) planes of the orthorhombic-type α-FeOOH crystal. The room-temperature UV-Vis absorption spectrum of the tubular α-FeOOH nanostructures is presented. 相似文献
993.
Chu C.-K. Huang H.-K. Liu H.-Z. Lin C.-H. Chang C.-H. Wu C.-L. Chang C.-S. Wang Y.-H. 《Microwave and Wireless Components Letters, IEEE》2007,17(2):151-153
This letter presents a compact X-band high gain and high power four-stage AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor (PHEMT) monolithic microwave integrated circuit (MMIC) high power amplifier (PA). This amplifier is designed to fully match a 50-Omega input and output impedance. Based on 0.35-mum gate-length power PHEMT technology, this PA MMIC is fabricated on a 3-mil thick wafer. While operating under 8 V and 2700-mA dc bias condition, the characteristics of 40-dB small-signal gain, a 10-W continuous-wave saturation output power, and 33% power added efficiency at 9.7GHz can be achieved 相似文献
994.
Tzyy-Jiann Wang Chia-Hong Chu 《Photonics Technology Letters, IEEE》2007,19(23):1904-1906
A wavelength-tunable microring resonator with integrated microheater on lithium niobate is presented. Ridge structure on lithium niobate is formed by a wet-etching technique for enhancing the lateral index contrast of the waveguide. The resonant wavelength of the microring resonator is tuned through thermooptic effect by injecting current into the integrated microheater. The tuning characteristics of through port and drop port are measured and the tuning rates in the microring resonator with a radius of 100 mum for transverse-magnetic and transverse-electric polarizations are 2.54 x 10-2 nm/mA and 3.40 x 10-3 nm/mA. 相似文献
995.
Mok K.R.C. Colombeau B.. Benistant F.. Teo R.S. Yeong S.H. Yang B.. Jaraiz M.. Chu S.-F.S. 《Electron Devices, IEEE Transactions on》2007,54(9):2155-2163
In this paper, accurate and advanced CMOS process and device simulations based on atomistic kinetic Monte Carlo (kMC) process simulator are presented. First, the methodology used to predict continuum 2-D/3-D doping profiles from 3-D atomistic distribution that can be directly transferred from process to device simulator is described. Calibration of damage evolution, dopant diffusion and clustering, interaction with interfaces, and the impact of impurities, which are crucial for accurate simulations, will be presented and discussed. Subsequently, comparison with a wide range of electrical-device characteristics showed that experimental results were remarkably well reproduced by the simulations. Finally, we shall demonstrate that device optimization can be achieved based on kMC process simulations, even for novel coimplant processes. This paves the way for the use of kMC in the design of devices and the optimization of device performance in technology computer-aided design for manufacturing. 相似文献
996.
Naiqi Wu Liping Bai Chengbin Chu 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2007,37(4):461-472
Recently, there has been a great interest in the modeling and analysis of process industry, and various models are proposed for different uses. It is meaningful to have a model to serve as an analytical aid tool in short-term scheduling for oil refinery process. However, in oil refinery process, there are special constraints and requirements, and the existing models cannot be applied directly. Thus, as an application in this paper, we extend the hybrid Petri net to model the crude-oil operations in oil refinery process. This Petri net is called controlled colored timed Petri net (CCTPN). In this model, a token carries both discrete and continuous properties. A token in a discrete place shows its discrete properties, while the continuous properties are captured when it is in a continuous place. A discrete transition treats a token just as a discrete one, and a continuous transition deals with it as a continuous one. In this way, we integrate the discrete and continuous processes together in the CCTPN. Based on the CCTPN, liveness for CCTPN is defined, and with the liveness definition we show how to detect conflicts in scheduling the system by using this model. 相似文献
997.
Xikui Li Xihua Chu D. C. Sheng 《International journal for numerical methods in engineering》2007,72(7):858-882
Based on the discrete particle model for solid-phase deformation of granular materials consisting of dry particulate assemblages, a discrete particle–continuum model for modelling the coupled hydro-mechanical behaviour in saturated granular materials is developed. The motion of the interstitial fluid is described by two parallel continuum schemes governed by the averaged incompressible N–S equations and Darcy's law, respectively, where the latter one can be regarded as a degraded case of the former. Owing to the merits in both Lagrangian and mesh-free characters, the characteristic-based smoothed particle hydrodynamics (SPH) method is proposed in this paper for modelling pore fluid flows relative to the deformed solid phase that is modelled as packed assemblages of interacting discrete particles. It is assumed that the formulation is Lagrangian with the co-ordinate system transferring with the movement of the solid particles. The assumed continuous fluid field is discretized into a finite set of Lagrangian (material) points with their number equal to that of solid particles situated in the computational domain. An explicit meshless scheme for granular materials with interstitial water is formulated. Numerical results illustrate the capability and performance of the present model in modelling the fluid–solid interaction and deformation in granular materials saturated with water. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
998.
一种基于贝叶斯网络的雷达重频模式识别方法 总被引:1,自引:0,他引:1
雷达重频模式指雷达脉冲重复间隔(PRI)的调制样式,重频模式识别对于雷达型号、类别识别具有重要支持作用,但这是一个较困难的过程,一般难以通过单一重频特征完成多种复杂重频模式的自动识别。本文为解决雷达多重频模式自动识别及识别抗噪声干扰问题,针对多种重频模式提取了几种PRI序列特征量(重频特征),然后引入了贝叶斯多网络分类器(BMNClassifier),利用所提取的特征量作为贝叶斯多网络分类器输入节点,通过贝叶斯多网络分类器的概率推理能力来实现雷达重频模式识别。 相似文献
999.
iPhone的发布在业内引起巨大轰动,这是继iPod之后苹果公司的又一巨作。iPhone的全触摸屏设计、强大的音乐功能对全球手机行业带来了强烈的冲击。分析了iPhone的优缺点,进一步阐述了苹果公司的发展战略,并透析了iPhone对全球手机行业所带来的影响。 相似文献
1000.
Hollow Cu nano/microstructures are prepared by reduction of CuSO4 · 5 H2O with glucose by using a mild hydrothermal process. The X‐ray powder diffraction and energy‐dispersive X‐ray analysis indicate that the products are pure Cu and of cubic phase. The morphology of the products can be controlled between nanotubes and microspheres assembled from hollow nanoparticles by adjusting the concentration of sodium dodecyl sulfate. A series of experiments confirm that the concentration of the glucose and NaOH also play important roles in the formation of the hollow Cu nano/microstructures. 相似文献