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61.
对智能电动机控制器的情况作了介绍,结合工作实践提出了维护要点和建议,并对该控制器的参数设置进行了说明,这对使用该设备的工业企业有一定的指导意义。 相似文献
62.
63.
Shu‐Li Sun Jing Ma Nan Lv 《International Journal of Adaptive Control and Signal Processing》2008,22(10):932-948
Based on the optimal fusion estimation algorithm weighted by scalars in the linear minimum variance sense, a distributed optimal fusion Kalman filter weighted by scalars is presented for discrete‐time stochastic singular systems with multiple sensors and correlated noises. A cross‐covariance matrix of filtering errors between any two sensors is derived. When the noise statistical information is unknown, a distributed identification approach is presented based on correlation functions and the weighted average method. Further, a distributed self‐tuning fusion filter is given, which includes two stage fusions where the first‐stage fusion is used to identify the noise covariance and the second‐stage fusion is used to obtain the fusion state filter. A simulation verifies the effectiveness of the proposed algorithm. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
64.
熊克齐 《石油化工管理干部学院学报》2003,(1):42-44
阐述了监理在建设项目施工阶段对投资控制的依据、投资控制的主要措施,及索赔过程中的时效、证据收集和评审原则。 相似文献
65.
Hung‐Yee Shu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(3):273-280
Liquid–liquid two‐phase epoxidation from cyclohexene and cyclooctene in aqueous potassium peroxymonosulfate (commercially available as Oxone®) solution was studied as an application in pollution prevention. To avoid potential emissions of volatile organic compounds an aqueous solution was employed to replace the usual chlorinated solvents used in epoxide production. A droplet column reactor and stirred tank reactor were used to investigate two‐phase synthesis of epoxide. An aqueous Oxone® solution was used to oxidize a dispersion of alkene droplets and form epoxide. The study of aqueous epoxidation in both reactors showed that the epoxidation of alkenes can be represented as a first order reaction with respect to alkene. The salting out effect of Oxone® concentration was studied in both reactors and found to be very similar at optimal conditions. In comparing the two reactors, it was found that the droplet column reactor produces larger quantities of product per unit reactor volume for the same reaction time. The objective of this study is to provide an alternative reactor design and synthesis route that can meet pollution prevention goals. Copyright © 2004 Society of Chemical Industry 相似文献
66.
基于因特网的远程校准技术进展 总被引:3,自引:0,他引:3
远程校准是信息技术特别是计算机网络技术与传统的计量测试技术结合的必然产物。本文介绍与之有关的一些概念及国外开展相应项目的情况。结合我们自己的一个实验装置.对在我国开展远程校准工作的必要性和可行性提出一些看法。 相似文献
67.
黄药合成工艺的生产实践 总被引:1,自引:0,他引:1
本文介绍了永平铜矿强力公司黄药合成的工艺概况 ,并论述了在生产实践中对提高产品质量所采取的主要措施 相似文献
68.
We present a multiple-channel video transmission scheme in wireless CDMA networks over multipath fading channels. We map an embedded video bitstream, which is encoded into multiple independently decodable layers by 3D-ESCOT video coding technique, to multiple CDMA channels. One video source layer is transmitted over one CDMA channel. Each video source layer is protected by a product channel code structure. A product channel code is obtained by the combination of a row code based on rate compatible punctured convolutional code (RCPC) with cyclic redundancy check (CRC) error detection and a source-channel column code, i.e., systematic rate-compatible Reed-Solomon (RS) style erasure code. For a given budget on the available bandwidth and total transmit power, the transmitter determines the optimal power allocations and the optimal transmission rates among multiple CDMA channels, as well as the optimal product channel code rate allocation, i.e., the optimal unequal Reed-Solomon code source/parity rate allocations and the optimal RCPC rate protection for each channel. In formulating such an optimization problem, we make use of results on the large-system CDMA performance for various multiuser receivers in multipath fading channels. The channel is modeled as the concatenation of wireless BER channel and a wireline packet erasure channel with a fixed packet loss probability. By solving the optimization problem, we obtain the optimal power level allocation and the optimal transmission rate allocation over multiple CDMA channels. For each CDMA channel, we also employ a fast joint source-channel coding algorithm to obtain the optimal product channel code structure. Simulation results show that the proposed framework allows the video quality to degrade gracefully as the fading worsens or the bandwidth decreases, and it offers improved video quality at the receiver. 相似文献
69.
采用喷射成形技术制备了Al1 0 Zn2 .9Mg1 .7Cu高强高韧铝合金沉积坯件 ,研究了喷射成形制备过程中各工艺参数对沉积坯件的成形性、显微组织、致密度的影响 ,确定了适当的工艺参数 ,研究了沉积坯件的热挤压及热处理工艺 ,对材料的组织进行了分析并对不同状态的材料性能进行了比较。研究结果表明 :当喷射成形工艺参数合理时 ,沉积坯件具有良好的成形性与致密度 ,在随后的热挤压过程中 ,通过较低的挤压比即可使材料达到全致密 ;通过对合金进行适当的热处理 ,材料的极限抗拉强度达到 810MPa ,同时延伸率保持在 8%~ 11% ,该材料是一种理想的轻质高强结构材料。 相似文献
70.