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Fuzzy Scheduling of Coupled Customers toa Queueing Network with Parallel Servers

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Systems Science and Systems engineering 1998年第4期8卷 482-487页

作者： ZHU Xiaomin(Department of Economics college of Economics and AdministratinNorthern jiaotong university Beijing 100044, china)ZHANG Runtong(Institute of information Systems college of Economics and AdministrationNorthern jiaotong university Beijing 100044,

In this paper we consider a queueing network consisting of two parallel servers and threearrival streams generated by independent Poisson sources. Each server has its own queue and receivescustomers from its own arrival stream. A third arrival stream consists of customers which place resourcedemands on both servers, which are handled separately by each server once the request is made. Eachservice time is independent and exponentially distributed. Each customer in the system pays a holdingcost per unit time. The objective is to dynamically determine the optimal scheduling policy to the thirdstream of conupled customers. based on the state of the system, so as to minimize the average cost. Thismodel is new, and has Policy implications for computer or communication networks. A fuzzy approachis presented to solve this problem. Simulation shows that the approach is efficient and promising.

关键词： Fuzzy Scheduling of Coupled Customers toa Queueing Network with Parallel Servers

基于前置维纳滤波的多用户MIMO系统下行链路线性预编码方法

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上海交通大学学报 2009年第7期43卷 1117-1120,1124页

作者：李旭何迪上海交通大学电子信息与电气工程学院上海200240

针对多用户多输入多输出(MIMO)下行链路中,用户接收机设计复杂度高且不易实现的问题,提出一种改进方案.利用维纳滤波的预处理方法,在发送端对发送数据进行预处理,把各用户接收机的计算任务集中于发送端,各移动用户接收机不需要预先得到... 详细信息

针对多用户多输入多输出(MIMO)下行链路中,用户接收机设计复杂度高且不易实现的问题,提出一种改进方案.利用维纳滤波的预处理方法,在发送端对发送数据进行预处理,把各用户接收机的计算任务集中于发送端,各移动用户接收机不需要预先得到其他用户的信道信息,降低了用户接收机的复杂度,有利于提高用户终端设备的高效节能和便携等特性.仿真结果表明,与现有方法相比,本文方法能有效改善系统的误码性能,并获得更大的信噪比增益.

关键词：多用户多输入多输出预编码维纳滤波

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求解复杂TSP问题的随机扰动蚁群算法

系统工程理论与实践 2002年第9期22卷 88-91,136页

作者：郝晋石立宝周家启重庆大学电气工程学院重庆400044 上海交通大学电子信息与电气工程学院上海200030

针对基本蚁群算法 ,设计出一种新颖的随机扰动蚁群算法 ,并将其应用于求解复杂 TSP问题 .该算法包含了两个重要方面 :一是提出了采用倒指数曲线来描述的扰动因子 ;二是设计出了相应的随机选择策略和扰动策略 .数值模拟表明 :该算法可以... 详细信息

针对基本蚁群算法 ,设计出一种新颖的随机扰动蚁群算法 ,并将其应用于求解复杂 TSP问题 .该算法包含了两个重要方面 :一是提出了采用倒指数曲线来描述的扰动因子 ;二是设计出了相应的随机选择策略和扰动策略 .数值模拟表明 :该算法可以有效地克服基本蚁群算法的计算时间较长和容易出现停滞现象的缺陷 ,具有更好的全局搜索能力 .此外。

关键词：复杂TSP问题随机扰动蚁群算法最优化问题模拟进化算法

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以太网技术在列车通信网络中的应用探讨

铁道车辆 2008年第12期46卷 25-28页

作者：彭国平杜亚江兰州交通大学机电技术研究所甘肃兰州730070

基于现有列车通信网络(TCN)不能完全满足信息传输的情况,提出了工业以太网和CAN总线共存的方案,介绍了基于高性能数字信号处理器TMS320F206的工业Ethernet的硬件接口电路、CAN/Ethernet网关模型等。

关键词：列车通信网络工业以太网 CAN总线 CAN/Ethernet网关

Hepatocellular carcinoma HepG2 cell apoptosis and caspase-8 and Bcl-2 expression induced by injectable seed extract of Coix lacryma-jobi

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Hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 303-307页

作者： Department of General Surgery (Lu Y and Zhang BY),Department of Bio-information (Jia ZX),Affiliated Medical college Hospital,Qingdao university,Qingdao 266003,china Shanghai jiaotong university School of Medicine,Shanghai 200025,china (Wu WJ) Department of Medicine,Heze Medical college,Heze 274000,china (Lu ZQ) [a] Department of General Surgery Affiliated Medical College Hospital Qingdao University Qingdao 266003 China [b] Department of Bio-information Affiliated Medical College Hospital Qingdao University Qingdao 266003 China [c] Shanghai jiaotong university School of Medicine Shanghai 200025 China [d] Department of Medicine Heze Medical College Heze 274000 China

BACKGROUND:Many Chinese herbs,especially herbal injections,have been shown to have anti-tumor effects in recent ***,since most reports focus on the clinical effectiveness of these herbs,their mechanisms of action are not well *** this study,we assessed apoptosis in the hepatocellular carcinoma (HCC) cell line HepG2 induced by an injectable extract from the seed of Coix lacryma-jobi (Semen coicis,SC),and monitored the expression of Bcl-2 and ***:Injectable SC was applied to HepG2 cells at different concentrations and the cells were collected 12,24 and 48 hours later.5-fluorouracil was used as a positive control group,and fluorescence-activated cell-sorting cytometry was used to measure the apoptosis rate of HepG2 cells and the expression of Bcl-2 and caspase-8 ***:SC induced apoptosis in HepG2 cells in a concentration and time-dependent manner,and the expression of caspase-8 was elevated and ***,it did not significantly influence the expression of ***:Injectable SC may induce apoptosis in HCC cells by regulating the expression of caspase-8.

关键词： Semen coicis traditional Chinese medicine Bcl-2 caspase-8 HepG2 cells apoptosis

DRAG REDUCTION EFFECT OF COUPLING FLEXIBLE TUBES WITH TURBULENT FLOW

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Journal of Hydrodynamics 2008年第1期20卷 96-100页

作者： CAI Shu-peng JIN Guo-yu LI Da-mei Yang Lin Institute of High Pressure Water Jet Hunan University of Technology Zhuzhou 421008 China State Key Laboratory of Water Resources and Hydropower engineering Science Wuhan University Wuhan430072 China college of Mechanical and electrical engineering Chongqing Jiaotong University Chongqing 400074 China

To analyze the mechanism of drag reducing effect by coupling flexible tubes with turbulent flow, based on experimental examination of more obvious turbulent drag reduction effect in flexible tubes than in rigid tubes, experimental investigation was performed on the effect of turbulent drag reduction, fluctuating vibration characteristics of flexible tube and the correlations by using a double-tube system and laser displacement sensor. The results are as follows： with the decrease of the thickness of the flexible tubes, the root mean square of fluctuating amplitude of the outer wall of the tubes increases, and the non-dimensional burst period increases, resulting in the increase of the reduction rate of drag coefficient by coupling flexible tubes with turbulent flow. At applied pressure-balanced air on the outer wall and the Reynolds number of about 1.75×10^4, the non-dimensional burst periods of the flexible tubes with the thickness of 2 mm, 3 mm, 4 mm are 141, 126, 105, respectively.

关键词： flexible tubes fluctuating displacement turbulent drag reduction burst period

基于非线性滤波和平滑相迭代的GPS定位估计算法

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上海交通大学学报 2009年第7期43卷 1108-1112页

作者：曹意茅旭初上海交通大学电子信息与电气工程学院上海200240

针对目前全球定位系统(GPS)单机定位精度较低的问题,提出一种新的定位估计算法.每一时刻点先用平淡卡尔曼滤波进行位置估计;然后,利用滤波结果对前一时刻点的位置估计进行平滑修正;接着,再用修正值进行滤波,得到当前时刻点更新的估计值... 详细信息

针对目前全球定位系统(GPS)单机定位精度较低的问题,提出一种新的定位估计算法.每一时刻点先用平淡卡尔曼滤波进行位置估计;然后,利用滤波结果对前一时刻点的位置估计进行平滑修正;接着,再用修正值进行滤波,得到当前时刻点更新的估计值,通过若干次迭代,得到最终估计值.后向平滑算法分别采用固定区间平滑和固定滞后平滑,前者适用于非线性系统模型,后者在平滑步长增大时,其计算量较小.实验结果表明,迭代算法能够有效提高定位精度,不仅可以应用于后验数据处理中,也可以应用于GPS实时定位估计.

关键词：全球定位系统最优平滑平淡卡尔曼滤波迭代算法

Grey Markov chain and its application in drift prediction model of FOGs

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Journal of Systems engineering and Electronics 2005年第2期16卷 388-393页

作者： Fan Chunling 1,2 , Jin Zhihua1, Tian Weifeng1 & Qian Feng11. Department of information Measurement Technology and Instrument, Shanghai jiaotong university,Shanghai 200030, P. R. china 2. college of Automation and Electric engineering, Qingdao university of Science and Technology,Qingdao 266042, P. R. china Department of information Measurement Technology and Instrument Shanghai Jiaotong University Shanghai 200030 P. R. China college of Automation and Electric engineering Qingdao University of Science and Technology Qingdao 266042 P. R. China

A novel grey Markov chain predictive model is discussed to reduce drift influence on the output of fiber optical gyroscopes (FOGs) and to improve FOGs' measurement precision. The proposed method possesses advantages of grey model and Markov chain. It makes good use of dynamic modeling idea of the grey model to predict general trend of original data. Then according to the trend, states are divided so that it can overcome the disadvantage of high computational cost of state transition probability matrix in Markov chain. Moreover, the presented approach expands the applied scope of the grey model and makes it be fit for prediction of random data with bigger fluctuation. The numerical results of real drift data from a certain type FOG verify the effectiveness of the proposed grey Markov chain model powerfully. The Markov chain is also investigated to provide a comparison with the grey Markov chain model. It is shown that the hybrid grey Markov chain prediction model has higher modeling precision than Markov chain itself, which prove this proposed method is very applicable and effective.

关键词： grey model Markov chain FOG drift.

Terahertz radiation sources based on free electron lasers and their applications

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Science china(information Sciences) 2012年第1期55卷 1-15页

作者： TAN Ping1,HUANG Jiang2,LIU KaiFeng2,XIONG YongQian2&FAN MingWu1,2 1Department of Electronic and information engineering,Huazhong university of Science and Technology,Wuhan 430074,china 2college of electrical and Electronic engineering,State Key Laboratory of Advanced Electromagnetic engineering and Technology,Huazhong university of Science and Technology,Wuhan 430074,china 1. Department of Electronic and information engineering Huazhong University of Science and Technology Wuhan 430074 China2. College of Electrical and Electronic Engineering State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan 430074 China

The tunability,high power and flexible picoseconds-pulse time structure of terahertz(THz)radiation make the THz free-electron laser(FEL)a very attractive THz source of coherent *** paper focuses on the development and perspectives of THz radiation sources based on the *** principles of the low gain THz FEL oscillator,the SASE THz FEL amplifier and the supperradiant THz FEL are reviewed briefly,and the key technologies of THz FEL,such as injector,accelerator,undulator and optical cavity,are discussed,*** current status of and future prospects for THz radiation sources based on the FEL are emphasized in this *** research and development have shown bright future in free-electron laser(FEL)THz radiation *** potential applications can be carried out in the field of imaging,material research,biology medicine,communication,diagnostics and many others.

关键词： terahertz source terahertz applications free electron laser