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Modeling and verifying Web services driven by requirements:An ontology-based approach

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Science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3,jin zhi1,2.& WU Budan1,4 1. {2. of Mathematics and Systems Science, chinese academy of sciences, beijing 100080, china 2. institute of computing technology, chinese academy of sciences, beijing 100080, china 3. institute of Software, chinese academy of sciences, beijing 100080, china 4. Graduate University of chinese academy of sciences, beijing 100049, china academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China institute of Software Chinese Academy of Sciences Beijing China institute of computing {2. Chinese Academy of Sciences Bejing China Graduate University of chinese academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Natural products inspired[3+2.cycloaddition enables efficient construction of hydroxylated tetrahydrofuran acetals and concise syntheses of lignans

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Science china Chemistry 2024年第7期67卷 2306-2313页

作者： Dong-Yue Cai Weiming Shi Zhao-Hui jin zhi-Xiang Yu jin-Xin Zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of chinese academy of sciences Beijing 100049China beijing National Laboratory for Molecular sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China

Mimicking biosynthetic pathways of hongkonoids led to the development of a new Cu(Ⅰ)-catalyzed[3+2.cycloaddition ofα-hydroxyketone andβ-keto enol ethers,affording tetrahydrofuran acetals in a highly diastereoselective manner and 100%atom *** studies on the mechanism disclosed a concerted but asynchronous Michael addition/aldol *** the same importance,this methodology provides a practical biomimetic approach for one-step construction of the dibenzylbutyrolactol lignan backbone starting from two phenyl propane derivatives,opening up a powerful new approach for lignan synthesis,which is showcased by succinct total syntheses of two biologically important aryltetralin-type lignans,β-apopicropodophyllin and *** the mild and operationally simple conditions,the developed chemistry might have a promising prospect in potential industrial applications.

关键词： [3+2.cycloaddition transition-metal catalysis tetrahydrofuran lignans natural products

Changes of the trace metals in ice core during 1915-2.16 in coastal eastern Antarctica

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Advances in Climate Change Research 2024年第4期15卷 596-608页

作者： jing-Wen LIU Chuan-jin LI Gui-Tao SHI Yan LIU {2.-Heng DU Ming-Hu ding Shao-Peng GAO Cun-De XIAO Shi-Chang KANG Bo SUN State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of chinese academy of sciences Beijing 100049China Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China institute of Tibetan Plateau and Polar Regions Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Instituie of the Tibetan PlateauChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Antarctic trace metal records provide important information for grasping the influence of human activities on the environment over the last *** CA2.16-75 ice core is located along the East Antarctic Zhongshan Station-Dome A,enhances the record of metals research in the East Antarctic region,and its high-resolution supplies data support for the study of high-frequency climatic drivers and the effect of human activities on the Antarctic environment.A thorough dataset on seven trace metals(Al,Fe,Mn,Cu,Zn,Ba and Pb)in a coastal ice core in eastern Antarctica during the previous 102.years(1915-2.16)is presented in this *** has the lowest concentration(9.51±2..95 pg g^(-1)),and Ba has the highest concentration(36.57±51.35 ng g^(-1)).Notable variations are observed between the pre-1968 AD and post-1968 AD phases for Mn,Zn and *** abrupt,remarkable increase in the concentrations coincided with the change of metal smelting production in the southern *** addition to this,it may also be related to local Antarctic scientific research *** and Fe,the primary crustal elements,are essentially obtained from soil dust;Cu shows high crustal enrichment factors(EFc,>10),indicating that it is notably affected by anthropogenic ***,the anthropogenic activities in the Southern Hemisphere have had an impact on lead deposition in *** study not only enriches the trace metal historical record along the Zhongshan Station-Dome A but also provides a high-resolution ice core record,which is very crucial for the reconstruction of trace metal concentration changes in the last 100 years.

关键词： Eastern Antarctica Ice core Trace metals Human activities

Lie Point Symmetries of Differential-Difference Equations

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Communications in Theoretical Physics 2004年第5期41卷 645-648页

作者： ding Wei~1 TANG Xiao-Yan~(2.3) 1 Department of Applied Mathematics,Shanghai Jiao Tong University,Shanghai 2.0030,china2.Department of Physics,Shanghai Jiao Tong University,Shanghai 2.0030,china3 State Key Laboratory of Scientific and Engineering computing,institute of Computational Mathematics and Scientific Engineering computing,academy of Mathematics and System sciences,the chinese academy of sciences,P.O.Box 2.19,beijing 100080,china Department of Applied Mathematics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China State Key Laboratory of Scientific and Engineering computing Institute of Computational Mathematics and Scientific Engineering Computing Academy of Mathematics and System Sciences the Chinese Academy of Sciences P.O. Box 2719 Beijing 100080 China

In this paper,the classical Lie group approach is extended to find some Lie point symmetries of differential-difference *** reveals that the obtained Lie point symmetries can constitute a Kac-Moody-Virasoro algebra.

关键词： Lie point symmetry differential-difference equation Kac Moody-Virasoro algebra

Effect of Y element on atomic structure, glass forming ability,and magnetic properties of FeBC alloy

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chinese Physics B 2024年第7期33卷 440-446页

作者：肖晋桦丁大伟李琳孙奕韬李茂枝汪卫华 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China institute of Physics Chinese Academy of SciencesBeijing 100190China Department of Physics and beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China

The atomic structure of amorphous alloys plays a crucial role in determining both their glass-forming ability and magnetic properties. In this study, we investigate the influence of adding the Y element on the glass-forming ability and magnetic properties of Fe_(86-x)Y_xB_7C_7(x = 0, 5, 10 at.%) amorphous alloys via both experiments and ab initio molecular dynamics simulations. Furthermore, we explore the correlation between local atomic structures and properties. Our results demonstrate that an increased Y content in the alloys leads to a higher proportion of icosahedral clusters, which can potentially enhance both glass-forming ability and thermal stability. These findings have been experimentally validated. The analysis of the electron energy density and magnetic moment of the alloy reveals that the addition of Y leads to hybridization between Y-4d and Fe-3d orbitals, resulting in a reduction in ferromagnetic coupling between Fe atoms. This subsequently reduces the magnetic moment of Fe atoms as well as the total magnetic moment of the system, which is consistent with experimental results. The results could help understand the relationship between atomic structure and magnetic property,and providing valuable insights for enhancing the performance of metallic glasses in industrial applications.

关键词： Fe-based amorphous alloy ab initio molecular dynamic simulation glass-forming ability magnetic properties

A New Taxoid from the Needles of Taxus × media Hicksii

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chinese Chemical Letters 1997年第12期8卷 0-0页

作者： Yong Li GAO jin Yun ZHOU Yi ding and Qi Cheng FANG({2. of Matcria Medica, chinese academy of Medical sciences and Peking Union Medital College beijing 100050) institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

A new taxoid with 5/716 taxane skeleton, named taxamedin A (1) was isolated from the needles of Taxus x media Hicksii. Its structure was elucidated by spectal analysis

关键词： A New Taxoid from the Needles of Taxus

Chiral quantum heating and cooling with an optically controlled ion

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Light(Science & Applications) 2024年第7期13卷 1393-1400页

作者： jin-Tao Bu Jian-Qi Zhang Ge-Yi ding Jia-Chong Li Jia-Wei Zhang Bin Wang Wen-Qiang ding Wen-Fei Yuan Liang Chen Qi Zhong Ali Keçebaş Şahin KÖzdemir Fei Zhou Hui jing Mang Feng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. University of the chinese academy of sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. Department of Engineering Science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. Department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical

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复杂场景中海量外存地形模型的实时绘制算法

系统仿真学报 2009年第20期21卷 6510-6514,6518页

作者：郎兵方金云韩承德中国科学院计算技术研究所空间信息处理技术实验室北京100190 中国科学院研究生院北京100049

针对地形相关复杂三维场景应用需求,提出一种海量地形外存实时绘制算法,该方法使用离散细节层次技术并结合视点相关动态连续细节层次选择。基于元网格连通边权值简化地表模型,并基于Hausdorff距离进行视点无关批LOD误差控制。提出一种... 详细信息

针对地形相关复杂三维场景应用需求,提出一种海量地形外存实时绘制算法,该方法使用离散细节层次技术并结合视点相关动态连续细节层次选择。基于元网格连通边权值简化地表模型,并基于Hausdorff距离进行视点无关批LOD误差控制。提出一种海量数据实时调度方法,通过分层增量控制,两级数据预取和改进的快速视锥裁减实现了对外存数据的动态装载与调度。实验表明,该算法处理海量地形数据时占用较低系统资源,从而能够在复杂场景环境下进行快速实时绘制。

关键词：地形绘制细节层次地表简化外存模型元网格

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移动数据库系统乐观事务处理策略

计算机研究与发展 2002年第10期39卷 1379-1387页

作者：丁治明孟小峰王珊中国科学院计算技术研究所北京100080 中国人民大学数据与知识工程研究所北京100872

在移动数据库系统中 ,计算平台的移动性、频繁的断接性以及长事务等特性使得传统的事务处理模式不再适用 .为了解决移动数据库中的事务处理问题 ,提出了一种新的移动事务处理模型——乐观两阶段提交移动事务模型 ( O2.PC-MT) .该模型采... 详细信息

在移动数据库系统中 ,计算平台的移动性、频繁的断接性以及长事务等特性使得传统的事务处理模式不再适用 .为了解决移动数据库中的事务处理问题 ,提出了一种新的移动事务处理模型——乐观两阶段提交移动事务模型 ( O2.PC-MT) .该模型采用乐观并发控制与两阶段提交协议相结合的方法 ,对移动事务的长事务特性提供了灵活与有效的支持 ;此外 ,该模型允许移动计算机分多次发送事务操作 ,且在事务执行的过程中可以任意移动 ,从而提供了对交互式事务及随意移动性的支持 .实验结果表明 ,与基于两段锁协议及其变形的其它移动事务处理模型相比 ,O2

关键词：移动数据库系统乐观事务处理策略移动计算乐观并发控制