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Empirical likelihood-based inference in a partially linear model for longitudinal data

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Science china Mathematics 2008年第1期51卷 115-130页

作者： xue liugen~(1+) & {2. lixing~2.1.college of Applied Sciences, beijing university of technology, beijing 10002., china 2.Department of Mathematics, Hong Kong Baptist university, Hong Kong, china college of Applied Sciences Beijing University of Technology Beijing 100022 China Department of Mathematics Hong Kong Baptist University Hong Kong China

A partially linear model with longitudinal data is considered, empirical likelihood to infer- ence for the regression coefficients and the baseline function is investigated, the empirical log-likelihood ratios is proven to be asymptotically chi-squared, and the corresponding confidence regions for the pa- rameters of interest are then constructed. Also by the empirical likelihood ratio functions, we can obtain the maximum empirical likelihood estimates of the regression coefficients and the baseline function, and prove the asymptotic normality. The numerical results are conducted to compare the performance of the empirical likelihood and the normal approximation-based method, and a real example is analysed.

关键词： partially linear model empirical likelihood confidence region longitudinal data 62.05 62.1. 62.2.

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： xue-Ling DAI~1 Ya-Xuan SUN~2.Zhao-Feng JIANG~2. 1 college of Life Science,Capital Normal {2.,beijing 100037,china 2.college of Applied Sciences and Humanities,beijing Union {2.,beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2.and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth Sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& zhu Jiang2.1. {2. of Environmental Sciences, Peking university, beijing 100871, china 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 1. college of Environmental Sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

3D building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG xue 1,WENG JingNong 1,2.XIA YuBin 2.WU Lun 3 & SUI ZhengWei 3 1 college of Software,Beihang {2.,beijing 100191,china 2.college of Computer,Beihang {2.,beijing 100191,china 3 Institute of Remote Sensing and GIS,Peking {2.,beijing 100871,china Beihang Univ Coll Software Beijing 100191 Peoples R China Beihang Univ Coll Comp Beijing 100191 Peoples R China Peking Univ Inst Remote Sensing & GIS Beijing 100871 Peoples R China

The real world is a three-dimensional(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3D geospatial data on the web.3D city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3D modeling 3D transparent building hierarchical models china Star web services

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, xue Qikun1 & ZHANG Ze2. 4 1. State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of Sciences, beijing 100080, {2. 2. Laboratory of Electron Microscopy, Institute of Physics, Chinese Academy of Sciences, beijing 100080, {2. 3. college of Physics and Engineering, Qufu Normal university, Qufu 2.3165, {2. 4. beijing university of technology, beijing 10002., {2. 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. college of Physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. beijing university of technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science china(Technological Sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,zhu TongYu1,WU DongDong2.DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang university,{2. 100083,china 2.{2. Transportation Information Center,{2. 100055,china 3 college of Arts & Science,{2. Union university,{2. 100083,china 1. State Key Laboratory for Software Development Environment Beihang University Beijing 100083 China 2. beijing Transportation Information Center Beijing 100055 China 3. college of Arts & Science Beijing Union University Beijing 100083 China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

Synergistic governance:china's roadmap to improved health through climate and clean air actions

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Environmental Science and Ecotechnology 2024年第4期20卷 14-15页

作者： Tao xue Tong zhu Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and BiostatisticsMinistry of Education Key Laboratory of Epidemiology of Major Diseases(PKU)School of Public HealthPeking University Health Science CentreBeijingChina SKL-ESPC and SEPKL-AERM College of Environmental Sciences and EngineeringCenter for Environment and HealthPeking UniversityBeijing100871China

The COP2.'s inaugural Health Day highlighted the growing recognition of the connection between climate and health,while china's State Council released its third air quality action plan aiming at ongoing health *** Synergetic Roadmap project[1],which aims to track china's progress towards carbon neutrality and clean air,provides valuable insights to answer a set of intriguing questions concerning environmental health determinants,their source sectors,and the methods for harmonizing disparate actions to maximize health gain.

关键词： concerning neutral clean

Biogas recovery from microwave heated sludge by anaerobic digestion

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Science china(Technological Sciences) 2010年第1期53卷 144-149页

作者： QIAO Wei1,WANG Wei2.zhu CuiPing3 & ZHANG ZhongZhi1 1 college of Chemical Science and Engineering,{2. university of Petroleum,beijing 102.49,{2. 2.Department of Environmental Science and Engineering,Tsinghua university,beijing 10084,{2. 3 J & K {2. Cleaning Energy technology Co.Ltd.,beijing 100085,{2. 1. college of Chemical Science and Engineering China University of Petroleum Beijing 102249 China2. Department of Environmental Science and Engineering Tsinghua University Beijing 10084 China3. J & K China Cleaning Energy Technology Co. Ltd. Beijing 100085 China

Biogas generated from sewage sludge,livestock waste,and food waste by anaerobic digestion is a valuable renewable energy ***,conventional anaerobic digestion is not an efficient process.A long hydraulic retention time and low biogas recovery rate hinder the applications of those *** effective pretreatment method to destroy sludge microbial cells has been one of the major concerns regarding improvement of the biogas *** article focuses on the effects of microwave heating on sludge anaerobic *** suspended solid(VSS) and chemical organic demand solubilization of heated sludge were *** heating was found to be a rapid and efficient process for releasing organic substrates from *** increase of organic dissolution ratio was not obvious when holding time was over 5 min with microwave *** effect of the VSS solubilization was primarily dependent on heating *** highest value of VSS dissolving ratio,36.4%,was obtained at 170°C for 30 *** COD dissolving ratio was about 2.% at 170°*** organic carbon of treated sludge liquor was 1.98 and 2.73 g/L at 150°C and 170°C for 5 min,respectively.A biochemical methane potential(BMP) test of excess sludge and a mixture of primary and excess sludge demonstrated an increase in biogas *** total biogas from microwave treated mixture sludge increased by 12.9% to 2..2. over control after 30 days of *** production was 11.1% to 2..9% higher for excess sludge than for untreated *** VS removal ratios of mixture sludge and excess sludge were 12. and 11% higher,respectively,compared to the untreated sludge.

关键词： biogas recovery microwave heating sludge anaerobic digestion

Bioinformatics analyses for signal transduction networks

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Science china(Life Sciences) 2008年第11期51卷 994-1002页

作者： LIU Wei1,2. LI Dong2. zhu YunPing2.& HE FuChu1,2.1.{2. of Mechanical & Electronic Engineering and Automatization, National university of Defense technology, Changsha 410073, china 2.State Key Laboratory of Proteomics, beijing Proteome Research Center, beijing Institute of Radiation Medicine, beijing 102.06, china 1. college of Mechanical & Electronic Engineering and Automatization National University of Defense Technology Changsha 410073 China 2. State Key Laboratory of Proteomics Beijing Proteome Research Center Beijing Institute of Radiation Medicine Beijing 102206 China

Research in signaling networks contributes to a deeper understanding of organism living activities. With the development of experimental methods in the signal transduction field, more and more mechanisms of signaling pathways have been discovered. This paper introduces such popular bioin-formatics analysis methods for signaling networks as the common mechanism of signaling pathways and database resource on the Internet, summerizes the methods of analyzing the structural properties of networks, including structural Motif finding and automated pathways generation, and discusses the modeling and simulation of signaling networks in detail, as well as the research situation and tendency in this area. Now the investigation of signal transduction is developing from small-scale experiments to large-scale network analysis, and dynamic simulation of networks is closer to the real system. With the investigation going deeper than ever, the bioinformatics analysis of signal transduction would have immense space for development and application.

关键词： signal transduction structural motif automated pathways regeneration dynamics simulation