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Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4,LI ZhengBin2.3.& LEI Yang1 1 Department of Physics,{2. university,beijing {3.,china 2.Department of Electrical Engineering and computer science,{2. university,beijing {3.,china 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,{2. university,beijing {3.,china 4 Committee of Yuanpei Honors Program,{2. university,beijing {3.,china Department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China Department of Electrical Engineering and computer science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53.billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

AutoProc: An automatic proactive replication scheme for P2. storage

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science china(Information sciences) 2011年第6期54卷 1151-1160页

作者： YANG Zhi & DAI YaFei computer science Department,{2.,{3., china 1. computer science Department Peking University Beijing 100871 China

Due to the prevalence of peer departures, P2. storage systems need to constantly generate replicas for high durability. However, few existing systems are able to select the right replication rate that balances replication cost and durability, e.g., minimizing replication cost without threatening the durability target. In this paper, we propose a method called AutoProc to automate the replication process in P2. storage systems. AutoProc employs two key techniques to enable cost-effective replication: correctly adapting replication rate with a reliability model, and replicating objects at the right order with a reliability indicator. Extensive simulations based on the real system failure trace show that AutoProc achieves the near-optimal performance.

关键词： P2. storage churn durability fault tolerance proactive replication resource usage

Some preservation of stability of modules

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Chinese science Bulletin 1997年第19期42卷 1596-1599页

作者： WANG HanpinDepartment of computer science and Technology.{2.,{3., china Department of computer science and Technology Peking University Beijing China

IN model theory, Zil’ ber has proved that any model of nontrivial -categorical theory is verysimilar to a module or field. So some people wanted to prove the famous Vaught’s conjec-ture for superstable theories of modules. Later, Buechler proved that the Vaught’s conjectureis true for the theories of modules with Morley rank 1. In order to reduce Vaught’s conjec-ture for superstablc theories of modules, Prest suggested discussing the preservation of stabili-ty--theory properties of modules when the underlying ring of the modules changes. Zieglergave some preservation theorems of clementary properties of the theory of modules in ref.

关键词： model theory ω-stahility superstability ring of fractions fractional module.

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& CHEN Bin2.1. beijing institute of Graphic Communication, beijing 102.00,{3. 2. Department of Mechanics & Engineering science, peking university, beijing 100871,{3. beijing institute of Graphic Communication Beijing 102600 China Department of Mechanics & Engineering science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3.1. Laboratory of Material in the Earth’s Interior, institute of Geochemistry, Chinese Academy of {2.s, Guiyang 550002. china 2. Department of Geology, china university of Geo{2.s, beijing 100083. china 3. Department of Geology, peking university,{12., china 1. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Department of Geology China University of Geosciences 100083 Beijing China 3. Department of Geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

3. 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 {3.,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(3.)space requiring that 3. geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3. 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 3. geospatial data on the web.3. 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 3. building model,an abstract of a 3. building model based on structure details is studied,and a novel representation approach named 3. transparent building hierarchical model is presented in this *** approach fully uses both the existing 3. 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 3. *** addition,based on the characteristics of the 3. building model data,a service-oriented architecture and Web service technologies for 3. city building models are *** aim of the approach is that 3. 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： 3. modeling 3. transparent building hierarchical models china Star web services

Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. {2. of Nuclear Physics and Chemistry, china Academy of Engineering Physics, Mianyang 62.900, china 2. Department of physics,{3., beijing 100871, china 3. {2. of Atomic and Molecular Physics, Sichuan university, Chengdu 610065, china 1. institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. Department of physics Peking university Beijing 100871 China 3. institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. Department of Pharmacology,School of Chemical Biology & Pharmaceutical sciences,Capital university of Medical sciences,{3. 100069,china 3.institute of Cardiovascular science at Health science Center,peking university {3. 100083.china 4 institute of Molecular Medicine and College of Life science,peking university,{3. 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China institute of Cardiovascular science at Health science Center Peking University Beijing 100083 China institute of Molecular Medicine and College of Life science Peking University Beijing 100871 China

Aim:Intracellular Ca2.plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2.and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2.sparkoccurrence and global Ca2.***,we hypothesized that Ca2.releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2.***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2.spark release（especially in the perinuclear area）and global Ca2.*** importantly,IP3. inhibitors,2.aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2.responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2.sparks α1 adrenergic stimulation cardiac hypertrophy

Another ID-Based Proxy Signature Scheme and Its Extension

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Wuhan university Journal of Natural sciences 2007年第1期12卷 33-36页

作者： ZHANG Jianhong1,2., ZOU Wei3.1. College of science, North{2. university of Technology, {3. 100041,china 2. institute of Software of Chinese Academy of sciences /State Key Laboratory of Information Security, {3. 100080,{2. 3. institute of {12. science and Technology, peking university,{13.,{2. College of science North China University of Technology Beijing China State Key Laboratory of Information Security Institute of Software of Chinese Academy of Sciences Beijing China institute of computer {2. and Technology Peking University Beijing China

So fur, the security of many proxy signatures has seldom been considered in a formal way and most of them cannot satisfy nonepudiation. In this work, a novel ID-based （Identity-based） proxy signature scheme is proposed by combining the proxy signature with ID-based public cryptography, and they formalize the notion of security for ID-based proxy signature schemes. And show that the security of the proposed scheme is secure. Compured with other proxy signature schemes, it does not need a secure channel. Thus, it is particularly suitable for the unreliable network computation environment. Finally, they extend proposed scheme to a proxy multi-signature which has the following advantages （1） the size of proxy multi- signature is independent of the number of delegating users; （2. the computation cost of proxy multi-signature only need two Weil paring.

关键词： proxy signature multisignature security proof