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PLS path model building:A multivariate approach to land price studies-A case study in Beijing

第十四届全国电磁兼容学术会议

作者： Pang Xiao-feng and Zhang An-ying Institute of Life Science and Technology,University of Electronic Science and Technology of china,Chengdu 610054,china,and {2. Centre for materials physics,chinese academy of sciences,shenyang 110015,P.R china

＜正＞ As known, we now come in the electromagnetic and electronic times. A variety of electronicand electric instruments, equipments, materials and components as well as television station andradiobroadcast stations, and so on, have been extensively used in mills and countryside and *** the electromagnetic waves or fields accompany always with us from morning to *** a case it is very necessary to know whether the electromagnetic waves including microwaves

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Progress in Natural Science:materials international 2009年第11期19卷 1643-1649页

作者： Wenjie Wu~(a,b),Wenzhong Zhang~(a,*) a Institute of Geographic sciences and Natural Resources Research,CAS,Beijing 100101,china b Graduate University of{2.,Beijing 100049,china Institute of Geographic sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China

Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel ***,the conventional statistical methods used in land analysis have some limitations,especially in cases of limited observational *** this paper,with the help of geographic information system(GIS) techniques,a partial least squares(PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of Beijing in *** a preliminary analysis,four latent variables are selected:accessibility of the workplace center,livability,traffic,and environment *** results show that the observation variables have a strong explanatory power for their corresponding latent variables,and the four latent variables have varying impacts on residential land *** the latent variables,accessibility to the workplace center has the strongest impact on the residential land price.

关键词： Land PLS path model GIS Beijing

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L.) with RAPD markers

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Progress in Natural Science:materials international 2005年第2期15卷 48-53页

作者： LI Xiaozun1*, PAN Junsong1*, WANG Gang1, TIAN Libo3, SI Longting3, WU Aizhong2.* and CAI Run1**(1. Agriculture and Biology School, Shanghai Jiaotong University, Shanghai 2.1101, china 2. Shanghai academy of Agricultural Science, Shanghai 2.1106, china 3. Horticulture School, shenyang Agricultural University, shenyang 110161, china) Agriculture and Biology School Shanghai Jiaotong University Shanghai 201101 China. Horticulture School Shenyang Agricultural University Shenyang 110161 China. Shanghai academy of Agricultural Science Shanghai 201106 China

A cucumber (Cucumis sativus L.) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD) and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52. with weak lateral growing ability and staminate from Dabieshan Mountains area in china and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2.and flanked by two markers, OP-Q5-1 and OP-M-2.2. at 9.3 cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2.and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM, respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.

关键词： cucumber (Cucumis sativus L.) lateral branch gynoecy RAPD genetic mapping

Adjustable character of microwave attenuation in BaTiO3 electrorheological fluids

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Progress in Natural Science:materials international 2002年第10期 35-40页

作者： FAN Jijun, ZHAO Xiaopeng , HUANG Min, GUAN Litao and WEN Lishi(1. Institute of Electrorheological Technology, 141# Northwestern Polytechnical University, Xi'an710072. china 2. Institute of Metal Research, chinese academy of sciences,{2., china) Institute of Electrorheological Technology 141# Northwestern Polytechnical University Xi'an 710072 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The behavior of microwave attenuation in BaTiO3 electrorheological fluids is studied when considering microwave propagation in the directions perpendicular and parallel to the particle chains, respectively. In the former case, the microwave attenuation increases with field strength when the particle concentration is low, and the increase of the particle concentration can also increase the microwave attenuation. However, when the particle concentration exceeds a critical value, the attenuation will first increase then decrease with field strength. At the same time, the higher the field strength, the greater the change of microwave attenuation. Moreover, there is a saturation field strength. When the field strength is lower than the saturated one, the change of microwave attenuation is fast. On the other hand, in the case of microwave propagation parallel to the particle chains, the microwave attenuation increases with the field strength monotonously. In addition, the variation of microwave attenuation wi

关键词： electrorheological fluids BaTiO3 microwave attenuation relaxation effect.

Electronic structure of edge dislocation of core-doped Ti in Fe

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Progress in Natural Science:materials international 2004年第6期 15-20页

作者： DANG Hongli 1 *,WANG Chongyu 1,2.3 and SHU Xiaolin 1(1. Central Iron and Steel Research Institute,Beijing 100081,china 2. Department of physics,Tsinghua University,Beijing 100084,china 3. international center for materials physics,Academica,shenyang 110016,china) Central Iron and Steel Research Institute，Beijing 100081，china Central Iron and Steel Research Institute，Beijing 100081，china Department of physics，Tsinghua University，Beijing 100084 China international center for {2. physics，Academica，shenyang 110016，china

The electronic structure of an edge dislocation doped Ti lying in the (001) plane with Burgers Vector along [100] direction in body-centered cubic iron is investigated using the first principles discrete variational method (DVM) based on the density-functional theory. The binding energy,impurity formation energy,interatomic energy,Mulliken orbital populations and charge density difference are presented in this paper. By calculating the binding energy of the clean dislocation system and the Ti-doped system,it is found that the binding energy of Ti-doped dislocation system is lower than that of the clean dislocation system,which implies that the Ti-doped dislocation system is more stable than the clean dislocation system. The calculated result of the impurity formation energy predicts the trapping effect of dislocation core for Ti,which shows that Ti atom prefers to occupy the place at the dislocation core. The calculated results of the interatomic energy and the difference charge density of dislocation doped Ti system indicate that the stronger bonding formed between the Ti impurity and its neighbor Fe atoms will affect the mechanical property of edge dislocation. Considering the influence of Ti on the electronic structure and the energies,we can predict that the trace Ti in transition metal Fe with dislocation defect can give a significant contribution to the solid solution hardening effects and will influence the mechanical property of materials.

关键词： edge dislocation doping effect electronic structure.

Blue-shift of Nano-Y_2._3 : Eu^(3+) Emission Spectra Excited by X-ray

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Journal of materials Science & Technology 1997年第4期13卷 351-353页

作者： Qiang LI Lian GAO and Dongsheng YAN(State Key Lab. of High Performance Ceramics & Superfine Microstructure, Shanghai Institute of Ceramics,chinese academy of {2., Shanghai 2.0050, china) State Key Lab. of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Nano-Y_2._3:Eu^(3+) powder was prepared by the homogeneous precipitation. With controlling the conditions of the reaction, nano powders with different grain size were obtained. It is found that the blue-shift phenomena exist in the nano-Y2.3:Eu3+ emission spectra excited by X-ray. The wave lengths of the peak (5D0→7F2. are related with the grain size of the powder

关键词： Eu Nano Emission Spectra Excited by X-ray Blue-shift of Nano-Y2.3

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umerical tests of efficiency of the retrospective time integration scheme in the self-memory model

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Progress in Natural Science:materials international 2004年第9期 89-92页

作者： GU Xiangqian 1*, YOU Xingtian 2. ZHU He 2.and CAO Hongxing 1(1. chinese academy of Meteorological {2., Beijing 100081, china 2. Training center of china Meteorological Administration, Beijing 100081, china)

A set of numerical tests was carried out to compare the retrospective time integral scheme in a self memory model, whose dynamic kernel is the barotropical quasi geostrophic model, with the ordinary centered difference scheme in the barotropical quasi geostrophic model. The Rossby Haurwitz wave function was taken as the initial fields for both schemes. The results show that in comparison with the ordinary centered difference scheme, the retrospective time integral scheme reduces by 2.orders of magnitude the forecast error, and the forecast error increases very little with lengthening of the time step. Therefore, the retrospective time integral scheme has advantages of improving the forecast accuracy, extending the predictable duration and reducing the computation amount.

关键词： numerical tests self-memory model retrospective time integral scheme.

块状LaNi_5基纳米合金的正电子湮灭研究

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中国稀土学报 2003年第3期21卷 299-302页

作者：隋郁熊良钺龙期威苏文辉哈尔滨工业大学理学院应用物理系凝聚态科学与技术研究中心黑龙江哈尔滨150001 中国科学院国际材料物理中心

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至2..6nm。利用正电子... 详细信息

利用高温高压技术,在不同的压力和温度(～4.5GPa,～800℃)下将LaNi5基快淬合金粉直接压制成了块状纳米晶合金。X射线衍射分析表明,高压使其晶粒内部发生了明显的压致晶粒碎化,其平均晶粒尺寸在4.5GPa下从75.5nm降至2..6nm。利用正电子湮灭技术研究了这种晶粒碎化效应对纳米合金内部缺陷结构的影响。测试结果表明,在高温高压的作用下,由于界面上原子的迁移和弛豫加剧,导致晶界上尺寸较大的微孔隙缺陷逐渐转化为尺寸较小的自由体积缺陷,使得纳米合金的致密度逐渐增强,显微硬度逐渐升高,从而在高温高压下得到致密的块状纳米合金材料。

关键词：凝聚态物理学压致碎化 LaNi5基合金纳米固体正电子湮灭稀土

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A measure of semantic similarity between gene ontology terms based on semantic pathway covering

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Progress in Natural Science:materials international 2006年第07期16卷 721-726页

作者： LI Rong, CAO Shunliang, LI Yuanyuan, TAN Hao, ZHU Yangyong, ZHONG Yang and LI Yixue ( Department of Computing and Information Technology, Fudan University, Shanghai 2.0433, china Shanghai center for Bioin-formation Technology, Shanghai 2.02.5, china School of Life sciences, Fudan University, Shanghai 2.0433, china Bioinfor-rnation center of Shanghai Institute for Biological sciences, chinese academy of sciences, Shanghai 2.0031, china) [a]Department of Computing an Information Technology Fudan University Shanghai China [b]Shanghai center for Bioinformation Technology Shanghai China [c]School of Life sciences Fundan University Shanghai China [d]Bioinformation center of Shanghai Institute for Biological sciences Chinese Academy of Sciences Shanghai China

Semantic similarity between Gene Ontology (GO) terms is critical in resolving semantic heterogeneousness when integrating heterogeneous biological databases. Traditionally, distance based and information content based measures are two major methods. In this paper, a new method based on semantic pathway covering is proposed and an algorithm, COMBINE algorithm, is presented, which considers information contents of two given nodes and those of all nodes included in the two nodes' pathways. Experiments show that COMBINE algorithm obtains the highest correlation index compared with those distance based and information content based algorithms.

关键词： Gene Ontology semantic similarity measure information content.