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31.
32.
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
33.
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
34.
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
35.
往复式压缩机管道的防振设计 总被引:1,自引:0,他引:1
分析了往复式压缩机管道产生振动的原因及影响因素,提出解决管道振动的方法及对策。 相似文献
36.
基于神经PID网络的串级调节系统研究 总被引:2,自引:0,他引:2
舒怀林 《自动化与仪器仪表》1997,(5):5-7
本文提出了一种神经PID网络控制器,并利用它构成串级调节系统。在给出网络结构和计算公式的基础上,进行了计算机仿真。仿真结果表明,神经PID网络控制器构成的串级调节系统具有良好的动态和静态性能及很强的抗扰能力。 相似文献
37.
介绍汽车加油站在防火设计与消防管理方面需注意的问题,主要包括站址选择、总平面布置、油罐设置、管线布置、卸油方式等方面,同时对加油站的日常操作与防火消防管理提出了要求。 相似文献
38.
本文利用等效工作站理论和工件流平衡原理,推导出非串行离散事件生产线可以等价于串联系统,并归结为装配和拆卸两条定理,解决了系统的建模、分析与设计问题。 相似文献
39.
中国碎屑岩隐蔽油气藏勘探进展与问题 总被引:1,自引:0,他引:1
介绍了中国陆上与海上碎屑岩隐蔽油气藏的勘探历程.总结了伴随碎屑岩隐蔽油气藏勘探过程中新理论新技术的进展情况,理论上包括层序地层理论在中国的不断创新、坡折带理论、复式输导体系、相势控藏及三元控藏理论,这些理论推动了隐蔽油气藏从个别识别到定性和定量预测,促进了盆地不同构造位置、不同层系、不同领域隐蔽油气藏的勘探;技术上主要体现在高精度层序地层研究、为高精度层序地层研究而发展的保幅处理和高分辨率处理技术、验证和预测隐蔽砂体的反演技术、隐蔽砂体快速直观识别的可视化技术、分析隐蔽砂体含油性的AVO技术及分频等地球物理技术.尽管如此,隐蔽油气藏勘探失败案例暴露了许多问题,这些问题在于缺乏系统运用隐蔽油气藏理论或者由于隐蔽油气藏成藏理论不完善难以准确快速评价是否成藏,此外,由于地球物理预测具有多解性也会导致错误的认识.因此,今后应充分利用高分辨率地震资料,大力推进叠前处理和反演技术,进一步弄清隐蔽油气藏成藏机理及主控因素. 相似文献
40.
Yong Ma Yong‐zhen Peng Xiao‐lian Wang Shu‐ying Wang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(10):1118-1124
The laboratory scale anaerobic–anoxic–aerobic (A2O) process fed with synthetic brewage wastewater was designed to investigate the effects of changing feed C/P ratio on the performance of biological nutrient removal (BNR) processes. In the experiment, the influent chemical oxygen demand (COD) concentration was kept at approximately 300 mg L?1 while the total phosphorus concentration was varied to obtain the desired C/P ratio. Results showed that when the C/P ratio was lower than 32, phosphorus removal efficiency increased as C/P ratio increased linearly, while when the C/P ratio was higher than 32, the P removal efficiency was maintained at 90–98%, and effluent P concentration was lower than 0.5 mg L?1. However, regardless of the C/P ratio, excellent COD removal (90% or higher) and good total nitrogen removal (75–84%) were maintained throughout the experiments. It was also found that very good linear correlation was obtained between COD uptake per unit P released in the anaerobic zone and C/P ratio. In addition, the P content in the wasted activated sludge increased with the decrease in the C/P ratio. Based on the results, it was recommended that the wastewater C/P ratio and its effects be incorporated into BNR design and operational procedures, appropriate C/P ratios were used to achieve the effluent treatment goals. Copyright © 2005 Society of Chemical Industry 相似文献