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Parameter identification theory of a complex model based on global optimization method

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3.1 College of Automotive engineering, South china University of Technology, Guangzhou 510640, china 2 Beijing Research Institute of Mechanical and {3. Technology, Beijing 100083. china 3.department of engineering Mechanics, Tsinghua University, Beijing 100084, china College of Automotive engineering South China University of Technology Guangzhou China Beijing Research Institute of Mechanical and electrical Technology Beijing China department of engineering Mechanics Tsinghua University Beijing China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

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 20003., P. R. china 2. College of Automation and Electric engineering, {3. University of Science and Technology,{3. 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.

Cryopreservation of amphioxus (Branchiostoma belcheri) spermatozoa

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Acta Oceanologica Sinica 2009年第2期28卷 96-102页

作者： XU Yuyan ZHANG Shicui VERAPONG Vuthiphandchai SUBUNTITH Nimrat College of Food Science and engineering Ocean University of China Qingdao 266003 China College of Marine Biology Ocean University of China Qingdao 266003 China department of Aquatic Science Burapha University Chonburi 20131 Thailand department of Microbiology and Environmental Science Program Faculty of Science Burapha University Chonburi 20131 Thailand

Amphioxus, Branchiostoma belcheri, a closest relative of vertebrates, is at a high risk of extinction due to a combination of low effective population size, altered native habitats and environmental pollution, yet little is known about cryopreservation of its gametes. This study deals with the cryopreservation of amphioxus senlen. The main findings are that （1） the extender of Yao et al. is the best one among the four extenders examined; （2） the appropriate ratio of semen to extender of Yao et al. plus cryoprotectant is from 1：5 to 1：7; （3. dimethyl sulfoxide （DMSO） and methanol are the better cryoprotectants than glycerol, with DMSO giving the best results; （4） the eggs fertilized with post-thaw spermatozoa are capable of developing to at least hatching stage, and the highest hatching rate is （12.4±3.0）%. This is the first report on freezing and thawing of amphioxus spermatozoa, providing a simple and practical protocol for cryopreservation of amphioxus spermatozoa and laying a foundation for safeguarding this endangered species.

关键词： amphioxus Branehiostoma beleheri cryopreservation spermatozoa motility

Effect of UV-B radiation on the population dynamics of the rotifer Brachionus urceus

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Acta Oceanologica Sinica 2011年第2期30卷 113-119页

作者： WANG Jinhe FENG Lei TANG Xuexi College of Marine Life Sciences Ocean University of China Qingdao 266003 China Dong Ying City Ocean and Fishery Bureau Dongying 257091 China department of Agricultural engineering Dongying Vocational College Dongying 257091 China

The effect of UV-B radiation enhancement at experimental doses of 0.00,0.24,0.48,0.72,0.96,and 1.20 kJ/m 2 on the population dynamics of the rotifer Brachionus urceus feeding on the alga Chlorella *** studied under controlled laboratory conditions using clonal culture and life-table *** results show that UV-B radiation treatment significantly shortened the survival time of the rotifer （P 0.05）： The longest survival time （3.6 h） occurred in the control （0.00 kJ/m 2 ） while the shortest （222 h） occurred when exposed to the highest UV-B radiation treatment （1.20 kJ/m 2 ）.The fecundity of the rotifer *** was enhanced by the lower UV-B radiation treatment （0.24 and 0.48 kJ/m 2 ） but inhibited by the higher treatments （0.96 and 1.20 kJ/m 2 ）.Life expectancy also was obviously affected by UV-B radiation （P 0.05）.The highest life expectancy occurred in the control （0.00 kJ/m 2 ）,and it became shorter with increasing doses of UV-B *** resutls in the present study indicate that the life expectancy of the rotifer *** can be used as an indicator for UV-B radiation enhancement.

关键词： UV-B radiation marine rotifer Brachionus urceus population dynamics

Study on interaction between macrocell and microcell in the early corrosion process of reinforcing steel in concrete

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Science china(Technological Sciences) 2010年第5期53卷 1285-1289页

作者： LI LanQiang1,DONG ShiGang1,WANG Wei2,HU RongGang1,DU RongGui1,LIN ChangJian1,ZHUO XiangDong1 & WANG Jia2 1 State Key Laboratory of Physical Chemistry of Solid Surfaces,department of Chemistry,College of Chemistry and Chemical engineering,Xiamen University,Xiamen 3.1005,china 2 College of Chemistry and Chemical engineering,Ocean University of china,qingdao 266100,china State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China College of Chemistry and Chemical engineering Ocean University of China Qingdao China

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement *** corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and *** was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic *** corrosion macrocell and microcell always exist during the corrosion *** interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.

关键词： reinforcing steel in concrete array electrode macrocell microcell

STUDY ON SYNTHESIS OF HIGH VINYL POLYBUTADIENE WITH TETRAVALENT MOLYBDENUM CATALYST SYSTEM

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高分子科学(英文版) 1986年第2期4卷 200-206页

作者：杨玉伟唐学明 department of Polymer engineering qingdao College of Chemical engineering qingdao qingdao

In this paper the catalytic behaviour of tetravalent molybdenum catalyst system in polymeriza-tion of butadiene is dealt with. The effects of the variety of apions combined with molybdenumatom, the pattern of the substituent R in （i-Bu）2AlOR and the polymerization conditions on thebutadiene conversion, the molecular weight and its distribution and the microstructure of the polymeralso are studied. It has been found that the catalyst system is significantly active when anions com-bined with the molybdenum atom are acetoxy （CH3.OO-）,or ethoxy （C2H5O-）. Obviously, thevariety of substituent R in （i-Bu）2 AlOR has a great influence on the catalytic activity. The catalystsystem is inactive if the R group is--COR’ （R’is alkyl or aromatic group） or alkyl, whereas the activityof the catalyst system increases if the R group is phenyl or tolyl. With the rise of polymerizationtemperature the polymer molecular weight decreases, the distribution index of molecular weight in-creases and the content of 1,2-unit in polybutadiene reduces.

关键词： substituent alkyl polymerization aromatic molybdenum butadiene acetoxy behaviour molar ethoxy

A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model

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Journal of Bionic engineering 2010年第2期7卷 199-208页

作者： Yinhan Gao~1,Jun Xie~2,Jie Liang~1,Xin Chang~3.Baojun Wu~2 1.Experimental Centre of Testing Science,Jilin University,Changchun 13.022,P.R.china 2.College of Instrumentation & electrical engineering,Jilin University,Changchun 13.061,P.R.china 3.Laboratory of Applications and Computations in Electromagnetics and Optics,department of electrical engineering, University of Washington,WA 98195-2500,USA Experimental Centre of Testing Science Jilin University Changchun P. R. China College of Instrumentation & electrical engineering Jilin University Changchun P. R. China Laboratory of Applications and Computations in Electromagnetics and Optics Department of Electrical Engineering University of Washington Seattle USA

Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave *** method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation ***, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical *** the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory ***, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were *** show thatthe proposed method was economical, simple, and with good evaluation quality.

关键词： sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological Sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2, WANG YinShun1 & ZHOU WeiWei3.1 Key Laboratory of HV and EMC Beijing, North china Electric Power University, Beijing 102206, china 2 department of Physics, Baoding University, Baoding 071000, china 3.Institute of electrical engineering, Chinese Academy of Sciences, Beijing 100190, china Key Laboratory of HV and EMC Beijing North China Electric Power University Beijing China department of Physics Baoding University Baoding China Institute of electrical engineering Chinese Academy of Sciences Beijing China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223.Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223.Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

Asynchronous cooperative communication systems:A survey on signal designs

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Science china(Information Sciences) 2011年第8期54卷 1547-1561页

作者： WANG HuiMing 1,2 & XIA XiangGen 3.1 School of Electronic and Information engineering, Xi’an Jiaotong University, Xi’an 710049,china 2 State Key Laboratory of Integrated Services Networks, Xidian University,Xi’an 710049, china 3.{3. of electrical and Computer engineering,University of Delaware,Newark,DE 19716,USA School of Electronic and Information engineering Xi’an Jiaotong University Xi’an China State Key Laboratory of Integrated Services Networks Xidian University Xi’an China department of electrical and Computer engineering University of Delaware Newark USA

Cooperative communications is a promising technique for future high speed wireless *** systems may be formulated as virtual multi-input multi-output (MIMO) systems where spatial/cooperetive diversity is a key advantage. However,different from MIMO systems,one of the major chal- lenges for cooperative communications systems is that the cooperative transmissions in cooperative systems may be neither time nor frequency synchronized,since the transmissions are from multiple cooperative nodes at different *** existing signal designs for co-located MIMO systems may not be able to collect the cooperative diversity in cooperative communications *** paper gives an overview of recent research efforts on combating the time and frequency asynchronism of the cooperative communication *** focus on the signal designs (or space-time codings/modulations) to achieve full cooperative diversity,and summarize some of the resent distributed space-timing coding and space-frequency coding techniques to combat timing errors and frequency offsets,and in the meantime to achieve full cooperative diversity,in both one-way and two-way cooperative networks.

关键词： cooperative communications time and frequency offsets space-time coding space-frequency codes full cooperative diversity linear receiver