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A NEW IMPLICIT SCHEME FOR SOLVING 3-D SHALLOW WATER FLOWS

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Journal of Hydrodynamics 2009年第6期21卷 790-798页

作者： ZHANG Zhuo SONG Zhi-yao LV Guo-nian State key laboratory of Hydrology Water Resources and Hydraulic Engineering Ocean College Hohai University Nanjing 210098 China key laboratory of Virtual Geographic environment Ministry of Education Nanjing Normal University Nanjing 210097 China

Based on the improved ADI method, this article proposes an improved implicit finite difference scheme for solving 3-D shallow water flows. The main objective is to design a numerical relation between the horizontal velocity on each layer and the depth-averaged velocity for employing the improved ADI method. With the free surface elevation and the depth-averaged velocity obtained by using essentially 2-D depth-averaged mode, the velocity profiles can be obtained easily and simultaneously. The wind-induced flows, the open channel flows due to the pressure gradient and the tidal flows in coastal waters are simulated, and the results are consistent well with the analytical solution and the field data, which shows that the present implicit scheme is stable and effective, and the established model is practical. Moreover, when only one vertical layer is specified, the present 3-D numerical model is reducea to the 2-D depth-averaged model.

关键词： shallow water equation ADI method wind-induced flow gravity-drived flow tidal flow

Capability description and discovery of Internetware entity

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Science china(Information Sciences) 2010年第4期53卷 685-703页

作者： WANG PuWei1*, JIN Zhi2,3* & LIU HongYan4 1key laboratory of Data Engineering and Knowledge Engineering of the ministry of education, Renmin University of china, Beijing 100872, china 2key laboratory of High Confidence Software Technologies of the ministry of education, Peking University, Beijing 100871, china 3Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100190, china 4Department of Management Science and Engineering, Tsinghua University, Beijing 100084, china key laboratory of Data Engineering and Knowledge Engineering of the ministry of education Renmin University of China Beijing China key laboratory of High Confidence Software Technologies of the ministry of education Peking University Beijing China Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Department of Management Science and Engineering Tsinghua University Beijing China

Internetware can be formed through aggregation of Internetware entities bottom-up to satisfy the user's requirements. In the process, capability description of Internetware entity plays an important role. This paper proposes a capability description of Internetware entity based on environment ontology. The environment ontology includes environment entities and possible interactions with the environment entities in a particular domain. Tree-like hierarchical state machines are also included in the ontology to describe domain life-cycle of the environment entities. On the basis of the ideas, the capability of Internetware entity is embodied by interacting with environment entities and the changes of the environment entities during the interactions. Finally, this paper describes the matchmaking between capability descriptions of Internetware entities to support the discovery of Internetware entity. An example of online education course is given to illustrate the ideas.

关键词： Internetware capability description domain environment ontology tree-like hierarchical state machine

Towards a degradation-based mechanism for adaptive overload control

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Science china(Information Sciences) 2012年第12期55卷 2708-2722页

作者： WANG ZiYou 1,2,ZHOU MingHui 1,2 & MEI Hong 1,2 1 Software Institute,School of Electronics Engineering and Computer Science,Peking University,Beijing 100871,china 2.key laboratory of High Confidence Software Technologies(Peking University),ministry of education,Beijing 100871,china Software Institute School of Electronics Engineering and Computer Science Peking University Beijing China ministry of education Key Laboratory of High Confidence Software Technologies (Peking University) Beijing China

Uncontrolled overload is one of the major causes of the system's decline in reliability and performance for web *** also harms the construction of trustworthy *** paper presents a degradationbased mechanism to adaptively control overload in complex,dynamic web *** our mechanism,the bottlenecks in the application's performance are determined by internally monitoring the performance and resource utilization state of the application,which is decomposed into a set of *** locating the bottlenecks,two decision algorithms are proposed to dynamically and adaptively generate proper degradation plans without *** degrading the service which consumes critical resources and has a low priority from the perspective of business logic,the application can keep providing key services even when overload *** implement a prototype and conduct a case study on a wiki *** also evaluate our approach and demonstrate its effectiveness in simulated overload *** handling overload,we make a breakthrough in building trustworthy software in an open,dynamic and rapidly changing environment.

关键词： overload service degradation resource monitoring performance management

Cells therapy for Parkinson's disease-so close and so far away

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Science china(Life Sciences) 2009年第7期52卷 610-614页

作者： REN ZhenHua & ZHANG Yu Cell Therapy Center,Xuanwu Hospital,Capital Medical University and key laboratory of Neurodegeneration,ministry of education,Beijing 100053,china Cell Therapy Center Xuanwu Hospital Capital Medical University and Key Laboratory of Neurodegeneration Ministry of Education Beijing China

One of the strategies of treating Parkinson's disease(PD) is the replacement of lost neurons in the substantia nigra with healthy dapamingergic *** sources for cells range from autologous grafts of dopamine secreting cells,fetal ventral mesencephalon tissue,to various stem cell *** the past quarter century,many experimental replacement therapies have been tried on PD animal models as well as human patients,yet none resulted in satisfactory outcomes that warrant wide *** progress in stem cell biology has shown that nuclear transfer embryonic stem cells(ntES) or induced pluripotent stem cells(iPS) derived cells can be used to successfully treat rodent PD models,thus solving the problem of immunorejection and paving the way for future autologous transplantations for treating ***,however,post mortem analysis of patients who received fetal brain cell transplantation revealed that implanted cells are prone to degeneration just like endogenous neurons in the same pathological area,indicating long-term efficacy of cell therapy of PD needs to overcome the degenerating environment in the brain.A better understanding of neurodegeneration in the midbrain appeared to be a necessary step in developing new cell therapies in Parkinson's *** is likely that future cell replacement will focus on not only ameliorating symptoms of the disease but also trying to slow the progression of the disease by either neuroprotection or restoring the micro-environment in the midbrain.

关键词： Parkinson’s disease dopamine neurons cell replacement transplantation stem cell fetal ventral mesencephalon carotid body embryonic stem cells nuclear transfer embryonic stem cells induced pluripotent stem cells

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2 & YIN Yingwu2,3 1. College of Chemistry & environment Protection Engineering, Southwest University for Nationalities, Chengdu 610041, china 2. TH-UNIS Insight Co., Ltd., Beijing 100085, china 3. key laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, ministry of education, Department of Chemistry, Tsinghua University, Beijing 100084, china College of Chemistry & environment Protection Engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China key laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2 h at 200℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Nature of the Precambrian metamorphic blocks in the eastern segment of Central Tianshan:Constraint from geochronology and Nd isotopic geochemistry

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Science china Earth Sciences 2004年第12期47卷 1085-1094页

作者： LIU Shuwen,GUO Zhaojie,ZHANG Zhicheng,LI Qiugen & ZHENG Haifei The key laboratory of Orogenic Belts and Crustal Evolution,ministry of education,china School of Earth and Space Sciences,Peking University,Beijing 100871,china The key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education China School of Earth and Space Sciences Peking University Beijing China

Granitoid gneisses are widespread in Precambrian metamorphic blocks of eastern segment of the Central Tianshan Tectonic Zone, and they have intrusive contact relationships with their metamorphic sedimentary country rocks of Proterozoic Xingxingxia and Kawabulag groups. Zircon U-Pb ages from a granodioritic gneiss (IW11-1) and a parametamorphic schist (W05-9) are determined at the Weiya area. Euhedral prismatic zircons from the granodioritic gneiss (IW11-1) provide U-Pb isotopic discordia intercept ages of 1218±17 Ma and 426±26 Ma, respectively, and euhedral prismatic zircons from the parametamorphic schist (W05-9) display U-Pb isotopic discordia intercept ages of 1216±74 Ma and 290±15 Ma, respectively. A whole-rock Sm-Nd isotopic isochron is determined in augen granitoid gneiss samples at the Gang- gou-Kumishi area and we obtain the isochron age of 1142±120 Ma, and its ε Nd (t) = -4.3. These geochronological data suggest that these Precambrian metamorphic basement blocks within eastern segment of the Central Tianshan Tectonic Zone can be produced during 1140—1220 Ma, and occur a nearly homochronous metamorphism. Integrated to these geochronological data, Nd depleted mantle model ages (T DM ) and epsilon Nd(t) values of these granitoid gneiss samples indicate that they can derive from mixing in various scales both magmas from mantle and crust sources at a late Mesoproterozoic active continental margin tectonic environment. Similarity in geochronology, Sm-Nd isotopic geochemistry between Weiya-Xingxingxia, Pargangtag and Ganggou-Kumishi areas suggests that they could be a bigger uniform metamorphic basement block, which could be formed by the assembly of the supercontinent Rodinia and be separated by late geological processes.

关键词： Central Tianshan Tectonic Zone, Precambrian metamorphic blocks, granitoid gneisses, isotopic chronolo-gy, active continental margin, supercontinent Rodinia.

Quenched moderate deviations principle for random walk in random environment

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Science china Mathematics 2010年第8期53卷 1947-1956页

作者： HONG WenMing 1 & WANG HuaMing 1,2 1 key laboratory of Mathematics and Complex Systems of ministry of education & School of Mathematical Sciences,Beijing Normal University,Beijing 100875,china 2 Department of Basic Courses,Business College,Beijing Union University,Beijing 100025,china key laboratory of Mathematics and Complex Systems of ministry of education & School of Mathematical Sciences Beijing Normal University Beijing China Department of Basic Courses Business College Beijing Union University Beijing China

We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and *** approach is based on hitting time decompos... 详细信息

关键词： random walk in random environment moderate deviations principle hitting time

Analysis of china’s Water Security and Virtual Water Trade

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Chinese Journal of Population,Resources and environment 2006年第4期4卷 18-23页

作者： Wang Hongrui1,2,Liu Xinghan3,Dong Yanyan1,2,Wang Junhong1,2 1.College of Water Sciences,Beijing Normal University,Beijing 100875,china 2.key laboratory for Water and Sediment Sciences ministry of education,Beijing 100875,china 3.College of Economics&Management,Beijing University of Technology,Beijing 100022,china College of Water Sciences Beijing Normal University Beijing 100875 China key laboratory for Water and Sediment Sciences ministry of education Beijing 100875 China College of Economics & Management Beijing University of Technology Beijing 100022 China College of Water Sciences Beijing Normal University Beijing 100875 China key laboratory for Water and Sediment Sciences ministry of education Beijing 100875 China College of Water Sciences Beijing Normal University Beijing 100875 China key laboratory for Water and Sediment Sciences ministry of education Beijing 100875 China

Producing goods and services all needs water *** water used in the process of an agricultural or industrial product is called the"Virtual Water"contained in this product. Through international trade,water-scarce countries and regions could purchase water-intensive products--especially foods,from water-rich countries to balance their water deficits and achieve water *** is one of the 13 most water-deficit countries whose water safety have been severely *** paper generalized the recent global research development and made a brief introduction about the methods calculating virtual water content in specific *** a case study,we qualified china's annual virtual water flows from year 2000 to 2002 with trade in crops,and ended with some policy advice for application and practice of virtual water strategy.

关键词： water security virtual water virtual water trade crops

Crustal Movement Patterns of china Continent Measured by GPS

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Geo-Spatial Information Science 2003年第4期6卷 57-60页

作者： YAO Yibin, Ph.D candidate, School of geodesy and Geomatics, wuhan University, 129 Luoyu Road, wuhan 430079, china. School of geodesy and Geornatics Wuhan University Wuhan China

This paper uses multi-quadric equations interpolation to es-tablish a widely covered and valuablespeed field model of china, withwhich the horizontal crustal movementpatterns are obtained. The present-dayvertical crustal movement velocity im-age of china is also expressed by GPSobservations, from which we canknow the vertical crustal movementpatterns.

关键词： multi-quadric equations interpolation speed field model crustal movementpattern