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The refined theory of transversely isotropic piezoelectric rectangular beams

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. college of Science, china Agricultural University, {2., china 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, Peking University, beijing 100871, china 1. college of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3 1 Center for Agriculture Water Research, china Agricultural University, beijing 100083, china 2.Chinese-Israeli International Center for Research and Training in Agriculture, china Agricultural University, beijing 100083, china 3 Water Conservancy and Civil Engineering college, Inner Mongolia Agricultural University, Hohhot 010018, china 1. Center for Agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2.Zhang Mei~1 Zhang Yi~2.(1.Department of Physical Chemistry,University of Science and Technology beijing,beijing 100083,{2. 2.Institute of Process Engineering,Chinese Academy of Sciences,beijing 100080,{2. 3.college of Engineering,Peking University,beijing 100871,{2.) [a]Department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]college of Engineering Peking University Beijing China [c]Institute of Process Engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2.4-KOH-O2.f oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2.rO4-H2.,KOH-KAlO2.H2., K（Na）OH-K（Na）2.O3-H2.,K（Na）OH-K（Na）HCO3-H2. and K（Na）HCO3-K（Na）2.rO4-H2. have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2.4can be oxidized across a wide range of temperature;K（Na）2.rO4can be separated from K（Na）AlO2.ystem at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2.rO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

The new interpretation of support vector machines on statistical learning theory

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Science china Mathematics 2010年第1期53卷 151-164页

作者： ZHANG ChunHua 1 , TIAN YingJie 2.& DENG NaiYang 3,1 School of Information, Renmin University of china, beijing 100872. china 2.Research Center on Fictitious Economy and Data Science, Chinese Academy of Sciences, beijing 100080, china 3 college of Science, china Agricultural University, beijing 100083, china 1. School of Information Renmin University of China Beijing 100872 China2. Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing 100080 China3. College of Science China Agricultural University Beijing 100083 China

This paper is concerned with the theoretical foundation of support vector machines (SVMs). The purpose is to develop further an exact relationship between SVMs and the statistical learning theory (SLT). As a representative, the standard C-support vector classification (C-SVC) is considered here. More precisely, we show that the decision function obtained by C-SVC is just one of the decision functions obtained by solving the optimization problem derived directly from the structural risk minimization principle. In addition, an interesting meaning of the parameter C in C-SVC is given by showing that C corresponds to the size of the decision function candidate set in the structural risk minimization principle.

关键词： C-support vector classification the minimization principle of the structural risk KKT conditions

Alkaline diagenesis and its genetic mechanism in the Triassic coal measure strata in the Western Sichuan Foreland Basin,china

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Petroleum Science 2009年第4期6卷 354-365页

作者： Jiang Zaixing Qiu Longwei Chen Guiju college of Energy China University of GeosciencesBeijing 100083China college of Earth Resources and Information China University of PetroleumShandong 257062China Sinopec Exploration and Production Research Institute Beijing 100083China

The reservoir of the upper Triassic Xujiahe Formation (T3x) in the Western Sichuan Foreland Basin is a set of terrigenous clastic rocks in an environment of coal measure sediments. Diagenesis greatly controls the physical properties of the reservoir through different responses of minerals to acidic and alkaline diagenetic environment. The dissolution of unstable components such as feldspar, rock fragments, carbonate cement, and clay minerals is the major source of secondary pores under acidic diagenesis, while the dissolution of quartz increases the reservoir space in the fault-fold zone of Longmen Mountain and Leikoupo paleo-hills. The dissolution of quartz is a result of cross-formation flow of fluid in the Himalaya epoch and the invasion of alkaline formation water from the Triassic Leikoupo and Jialingjiang formations through fault and fracture systems. In the vertical succession, acidic dissolution occurs at a shallow depth of less than 2.180 m, and alkaline dissolution occurs at a greater depth of more than 2.2.0 m. The reservoir space is formed by the influence of both acidic and alkaline dissolution in the depth interval of 2.180–2.2.0 m.

关键词： Sichuan Basin upper Triassic alkaline diagenesis porosity genetic mechanism

Biasing fluctuation model for directional stepping motion of molecular motor

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Chinese Science Bulletin 1998年第22期43卷 1879-1882页

作者： BAO Jingdong 1 and ZHUO Yizhong 2.1. beijing Meteorological college, beijing 100081, china 2. china Institute of Atomic Energy, beijing 102.13, china beijing Meteorological college Beijing China china Institute of Atomic Energy Beijing China

The biasing fluctuation model with a colored noise is presented to study the directional stepping motion of the molecular motor. The expression of probability current is obtained in the adiabatic approximation. The fo... 详细信息

关键词： molecular motor stepping motion biasing force colored noise Langevin equation.

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, beijing 100044, china 2. {2. of Earth Sciences and Resources, china University of Geo-sciences, beijing 100083, china Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China college of Earth Sciences and Resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, beijing 100049, china 2. {2. of Chemistry and Molecular Engineering, Peking University, beijing 100871, china 3. Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, beijing 100083, china 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of Chemistry and Molecular Engineering Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. Department of Mathematics, beijing Normal University, beijing 100875, {2. 2. Department of Mathematics, Neijiang Teacher's college, Neijiang 641112. {2.) beijing Normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators