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Kinetic theory of self-condensing vinyl polymerization

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Science china Chemistry 2010年第12期53卷 2429-2439页

作者： ZHOU ZhiPing 1 & YAN DeYue 2.1 school of Materials Science and Engineering,Jiangsu University,Zhenjiang 2.2.13,china 2.school of Chemistry and Chemical Engineering,shanghai Jiao Tong University,shanghai 2.02.0,china 1. school of Materials Science and Engineering Jiangsu University Zhenjiang 212013 China2. School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

This review introduces the kinetic theory of self-condensing vinyl polymerization (SCVP),including the SCVP of AB inimers,the SCVP with non-equal reactivity between A and B groups,the SCVP in the presence of a small amount of multifunctional initiators,also the SCVP of both inimers and *** analytical expressions of various molecular parameters for the resulting hyperbranched polymers,such as the molecular size distribution function,the average molecular weight,the polydispersity index and the degree of branching,are reviewed systematically.

关键词： kinetic theory self-condensing vinyl polymerization (SCVP) hyperbranched polymers

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1, GOU Chenhua1, 2.& ZHANG Na1 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, china 2. graduate {2., Chinese Academy of Sciences, Beijing 100080, china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. graduate school Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

Locating the Polar Cap Boundary of Postnoon Sector from Observations of 630.0 nm Auroral Emission at Zhongshan Station

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 59-64页

作者： Liu Li-gang 1, Ai Yong 1, Liu Rui-yuan 2. Yang Hui-gen 2.1. school of Electronic Information, Wuhan University, Wuhan 430072. Hubei, china 2. Polar Research Institute of china, shanghai 2.012., china Wuhan University School of Electronic Information Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Polar Research Institute of china Shanghai China (GRID:grid.418683.0) (ISNI:***)

We studied the ground observations of 630.0 nm auroral emission at Zhongshan Station to determine the polar cap boundary with the latitudinal profile of emission intensity. The open-closed field time boundary is assumed to lie at the boundary between polar rain and plasma sheet precipitation. We assume that nonprecipitation-dependent sources of 630.0 nm emission cause a spatially uniform luminosity in the polar cap and that auroral zone luminosity is also spatially uniform. Therefore we determine the location of the polar cap boundary of postnoon sector from the auroral emission data each time by finding the best fit of the observations to a step function in latitude and we produce a time series of the location of the polar cap boundary. The average error of the practice in the paper is less than 0.8 degree.

关键词： polar cap boundary aurora Zhongshan Station

Prediction method for October 2.03 solar storm

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Science china(Technological Sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2. 3, WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2.1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100080, china 2. graduate {2., Chinese Academy of Sciences, Beijing 100039, china 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 2.1101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 2. and 2., 2.03, this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Rietveld Quantitative Analysis of Carbides Precipitation in Normalized-tempered 2.2.Cr-1Mo-0.2.V Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 922-926页

作者：张永涛张汉谦 school of Materials Science and Engineering Shanghai Jiaotong University Research Institute Baoshan Iron & Steel Co.Ltd.

The quantitative determination of the mass fractions of precipitates in steels is very difficult using traditional materials characterization techniques. The Rietveld full-pattern fitting algorithm was introduced to solve this problem. The precipitated multicomponents’ mass fraction of M3C, MC, M7C3 and M2.C6 were evaluated precisely and relatively quickly. It is found evolution of carbides apparently occurs during tempering at high temperatures, and a two-step transformation mechanism is proposed for M7C3 during early tempering treatment. The method is an effective way on the investigation of precipitation kinetics, which may play a promising role in propertities’ enhancement and design of the heat-resistant steels.

关键词： 2.2.Cr-1Mo-0.2.V steel rietveld quantitative analysis precipitates

Data fusion for target tracking in wireless sensor networks using quantized innovations and Kalman filtering

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Science china(Information Sciences) 2012年第3期55卷 530-544页

作者： XU Jian1,2., LI JianXun1,2.& XU Sheng3 1Department of Automation, Science and Technology on Avionics Integration Laboratory, shanghai Jiao Tong University, shanghai 2.02.0, {2. 2.epartment of Automation, System Control and Information Processing, Ministry of Education of {2., shanghai Jiao Tong University, shanghai 2.02.0, {2. 3school of Mechanical Engineering, shanghai Jiao Tong University, shanghai 2.02.0, {2. 1. Department of Automation Science and Technology on Avionics Integration Laboratory Shanghai Jiao Tong University Shanghai 200240 China2. Department of Automation System Control and Information Processing Ministry of Education of China Shanghai Jiao Tong University Shanghai 200240 China3. School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

A novel networked data-fusion method is developed for the target tracking in wireless sensor networks (WSNs). Specifically, this paper investigates data fusion scheme under the communication constraint between the fusion center and each sensor. Such a message constraint is motivated by the bandwidth limitation of the communication links, fusion center, and by the limited power budget of local sensors. In the proposed scheme, each sensor collects one noise-corrupted sample, performs a quantizing operation, and transmits quantized message to the fusion center. Then the fusion center combines the received quantized messages to produce a final estimate. The novel data-fusion method is based on the quantized measurement innovations and decentralized Kalman filtering (DKF) with feedback. For the proposed algorithm, the performance analysis of the estimation precision is provided. Finally, Monte Carlo simulations show the effectiveness of the proposed scheme.

关键词： data fusion target tracking limited bandwidth quantized innovation Kalman filtering

A cumulant-based parameter estimation algorithm for near-field sources

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Progress in Natural Science:Materials International 2007年第8期17卷 900-905页

作者： Liang Junli~(1,2.) Yang Shuyuan~(1,2. Zhang Junying~3 (1.Institute of Acoustics,Chinese Academy of Sciences,Beijing 100080,china 2.graduate {2.,Chinese Academy of Sciences,Beijing 100039,china 3.National Laboratory of Radar Signal Processing,Xidian University,Xi'an 710071,china) [a]Institute of Acoustics Chinese Academy of Sciences Beijing China [b]graduate school Chinese Academy of Sciences Beijing China [c]National Laboratary of Radar Signal Processing Xidian University Xi'an China

To efficiently use the array aperture and avoid the complicated parameter pairing computation,this paper proposes a new cumulant-based algorithm for localizing near-field narrowband ***,this algorithm proposes a symmetric uniform linear ar- ray (ULA),and constructs three cumulant matrices by using the fourth-order cumulants of some properly chosen sensor outputs;second- ly,unlike the conventional parallel factor (PARAFAC) analysis models in data or subspace domain,it forms a three-way array (TWA) in the fourth-order cumulant domain using the three matrices,and analyzes the uniqueness of its low-rank decomposition;thirdly,it jointly estimates the frequency,the direction-of-arrival (DOA),and the range of each near-field source from the matrices via the low-rank de- composition of the *** simulation results are presented to validate the performance of our proposed method.

关键词： array signal processing localization cumulant parallel factor (PARAFAC) analysis three-way array (TWA)

Study of Product Quality Information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept

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厦门大学学报（自然科学版） 2002年第S1期41卷 234-235页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2. YU Xin-qi 2. RUAN Xin 3 (1. Ordance Institute of General Equipment Department, Shijiazhuang 05 0000, china 2. graduate {2. of Chinese Academic of Science, Beijing 100042. china 3. East china University of Science and Technology, shanghai 2.02.2. china 4. Meterology Bureau of Hebei Province, Shijiazhuang 05002., china)

The 2.th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of china and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:*** type of qua

关键词： product guality information decision-making sup port system of management of guality information people’s guality concept

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological Sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2.ZHANG Lei1,3 & XU JianZhong1,2.1 Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,china 2.Key Laboratory of Wind Energy Utilization,Chinese Academy of Sciences,Beijing 100190,china 3 {2. school of Chinese Academy of Sciences,Beijing 100190,china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing 100190 China3. Graduate School of Chinese Academy of Sciences Beijing 100190 China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2.2.0 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge