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Web服务组合中业务流程演化影响范围判定方法 被引量:2
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作者 尤殿龙 申利民 刘芳 《计算机集成制造系统》 EI CSCD 北大核心 2013年第7期1704-1714,共11页
针对组合业务流程中各参与演化的服务对彼此内部业务流程不可知的特点,依据互模拟理论,以服务在演化前后内部业务流程的变化特点判定演化类型;通过判定内部业务流程中受影响状态节点的前驱状态集或后继状态集的归属服务来确定受波及的服... 针对组合业务流程中各参与演化的服务对彼此内部业务流程不可知的特点,依据互模拟理论,以服务在演化前后内部业务流程的变化特点判定演化类型;通过判定内部业务流程中受影响状态节点的前驱状态集或后继状态集的归属服务来确定受波及的服务;通过计算服务内部业务流程演化影响范围的边界得出单个服务的受影响范围,进而得出服务组合中业务流程演化的影响范围。针对以上问题,给出了其判定规则和算法,使得演化仅在受波及区域内发生,并且所有受影响的状态节点都可能参与演化。 展开更多
关键词 服务组合 服务编排 业务流程演化 影响范围 判定方法 WEB服务
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基于规则的流程演化机制 被引量:2
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作者 陈静 王建民 《计算机工程与应用》 CSCD 北大核心 2006年第34期150-153,177,共5页
当今的业务流程系统在支持流程变更方面还不太理想,尤其是对于正在执行的流程变更处理。提出了一种基于规则的流程演化机制以使流程对于那些最终会表现为时间延迟的变更能够动态的进化。本机制阐述了如何检测最终表现为时间延迟的变更... 当今的业务流程系统在支持流程变更方面还不太理想,尤其是对于正在执行的流程变更处理。提出了一种基于规则的流程演化机制以使流程对于那些最终会表现为时间延迟的变更能够动态的进化。本机制阐述了如何检测最终表现为时间延迟的变更以及系统如何利用人的知识使流程动态演化。 展开更多
关键词 流程演化 规则 人机交互
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基于关系依赖模型的微服务流程演化分析 被引量:1
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作者 郑伟波 李志超 +1 位作者 刘纪遵 刘士军 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第2期309-319,共11页
微服务技术的快速发展为企业系统集成和网络化业务协同提供了技术支持,软件服务系统中的流程需要不断演化以适应业务变化的需求,而现有的研究多从单一维度评估服务流程演化的影响.提出包括流程层和服务层在内的服务系统双层依赖关系模型... 微服务技术的快速发展为企业系统集成和网络化业务协同提供了技术支持,软件服务系统中的流程需要不断演化以适应业务变化的需求,而现有的研究多从单一维度评估服务流程演化的影响.提出包括流程层和服务层在内的服务系统双层依赖关系模型DoubleDM,从服务演化和流程演化两个方面分析服务系统演化问题.针对服务层演化,基于服务间的依赖关系分析服务变更的影响范围,给出了服务依赖关系表达、依赖关系演化影响范围及求解和相应算法;针对流程演化的不同类型,给出了流程依赖基础上的流程化简处理步骤和算法.最后给出了微服务系统中流程演化的实现逻辑,并以微服务系统处理供应链销售流程为例进行了分析. 展开更多
关键词 流程 服务 依赖模型 业务流程演化
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RGPS支持的面向方面网络式软件演化方法
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作者 田刚 何克清 +2 位作者 孙承爱 崔焕庆 彭珍连 《计算机工程与科学》 CSCD 北大核心 2013年第9期110-116,共7页
为了改进现有的面向方面网络式软件演化方法中切入点(Pointcuts)位置定义不够清晰和切入点织入操作性不强的问题,提出一种利用角色-目标-流程-服务(RGPS)的流程元模型改进面向方面的网络式软件演化的方法。在该方法中,使用RGPS的流程元... 为了改进现有的面向方面网络式软件演化方法中切入点(Pointcuts)位置定义不够清晰和切入点织入操作性不强的问题,提出一种利用角色-目标-流程-服务(RGPS)的流程元模型改进面向方面的网络式软件演化的方法。在该方法中,使用RGPS的流程元模型定义流程,采用元模型中的控制结构定义方面切入点的位置,因为方面和流程采用一致的定义方式,所以方面切入点位置定义精确且能够无缝织入原流程。对流程演化过程给出了形式化的定义,并阐述了流程演化时方面织入的各种方式。最后利用一个实例说明了演化方法的方面织入过程。 展开更多
关键词 流程演化 RGPS元模型 面向方面 网络式软件
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Dynamic behavior of rock during its post failure stage in SHPB tests 被引量:14
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作者 周子龙 赵源 +3 位作者 江益辉 邹洋 蔡鑫 李地元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期184-196,共13页
In order to investigate the micro-process and inner mechanism of rock failure under impact loading, the laboratory tests were carried out on an improved split Hopkinson pressure bar (SHPB) system with synchronized m... In order to investigate the micro-process and inner mechanism of rock failure under impact loading, the laboratory tests were carried out on an improved split Hopkinson pressure bar (SHPB) system with synchronized measurement devices including a high-speed camera and a dynamic strain meter. The experimental results show that the specimens were in the state of good stress equilibrium during the post failure stage even when visible cracks were forming in the specimens. Rock specimens broke into strips but still could bear the external stress and keep force balance. Meanwhile, numerical tests with particle flow code (PFC) revealed that the failure process of rocks can be described by the evolution of micro-fractures. Shear cracks emerged firstly and stopped developing when the external stress was not high enough. Tensile cracks, however, emerged when the rock specimen reached its peak strength and played an important role in controlling the ultimate failure during the post failure stage. 展开更多
关键词 rock dynamics post failure stress equilibrium crack evolution particle flow code
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An Integral Research of the Flow of a Liquid Film Along a Vertical Wavy Wall
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作者 Jinsheng Shi 《Journal of Energy and Power Engineering》 2013年第5期899-902,共4页
An approximate research on the flow of a two dimensional, steady laminar liquid film along a vertical, long periodic wavy wall is conducted based on boundary layer integration. An ordinary equation about the film evol... An approximate research on the flow of a two dimensional, steady laminar liquid film along a vertical, long periodic wavy wall is conducted based on boundary layer integration. An ordinary equation about the film evolution is derived. By analyzing the integral equation of the hydrodynamic boundary layer under different Reynolds number domains, the flow characteristics are studied preliminarily. Influences of wall waviness, flow rate on the film development are discussed. 展开更多
关键词 Liquid film wavy wall boundary layer.
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Three-Step Difference Scheme for Solving Nonlinear Time-Evolution Partial Differential Equations
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作者 GONG Jing WANG Bin JI Zhong-Zhen 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第6期423-427,共5页
In this paper, a special three-step difference scheme is applied to the solution of nonlinear time-evolution equations, whose coefficients are determined according to accuracy constraints, necessary conditions of squa... In this paper, a special three-step difference scheme is applied to the solution of nonlinear time-evolution equations, whose coefficients are determined according to accuracy constraints, necessary conditions of square conservation, and historical observation information under the linear supposition. As in the linear case, the schemes also have obvious superiority in overall performance in the nonlinear case compared with traditional finite difference schemes, e.g., the leapfrog(LF) scheme and the complete square conservation difference(CSCD) scheme that do not use historical observations in determining their coefficients, and the retrospective time integration(RTI) scheme that does not consider compatibility and square conservation. Ideal numerical experiments using the one-dimensional nonlinear advection equation with an exact solution show that this three-step scheme minimizes its root mean square error(RMSE) during the first 2500 integration steps when no shock waves occur in the exact solution, while the RTI scheme outperforms the LF scheme and CSCD scheme only in the first 1000 steps and then becomes the worst in terms of RMSE up to the 2500th step. It is concluded that reasonable consideration of accuracy, square conservation, and historical observations is also critical for good performance of a finite difference scheme for solving nonlinear equations. 展开更多
关键词 three-step difference scheme NONLINEAR square conservation accuracy historical observations
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Relationship between the Flow Blockage of Tip Leakage Vortex and its Evolutionary Procedures inside the Rotor Passage of a Subsonic Axial Compressor 被引量:8
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作者 DU Hui YU Xianjun +1 位作者 ZHANG Zhibo LIU Baojie 《Journal of Thermal Science》 SCIE EI CAS CSCD 2013年第6期522-531,共10页
The near casing flow fields inside the rotor passage of a 1.5 stage axial compressor with different blade-loading levels and tip gap sizes were measured by using stereoscopic particle image velocimetry(SPIV). Based on... The near casing flow fields inside the rotor passage of a 1.5 stage axial compressor with different blade-loading levels and tip gap sizes were measured by using stereoscopic particle image velocimetry(SPIV). Based on a carefully defined blockage extracting method, the variations of blockage parameter inside the blade passage were analyzed. It was found that the variation of blockage parameter appeared as a non-monotonic behavior inside the blade passage in most cases. This non-monotonic behavior became much more remarkable as the blade loading increases or mass flow rate decreases.The variations of the blockage parameter inside the blade passage had close relation to the evolutionary procedures of the tip leakage vortex(TLV). The destabilization of the TLV caused a rapid increasing of the blockage parameter. After the TLV lost the features of a concentrated streamwise vortex,the blockage parameter usually got a peak value. And then, because of the intense turbulent mixing between the TLV low momentum flow and its surrounding flows, the flow deficit inside the TLV recovered. 展开更多
关键词 tip leakage vortex flow blockage unsteady flow axial compressor TURBOMACHINERY
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Progress of Jinping Underground laboratory for Nuclear Astrophysics(JUNA) 被引量:9
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作者 WeiPing Liu ZhiHong Li +61 位作者 JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第4期1-7,共7页
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire... Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 展开更多
关键词 direct measurement underground laboratory (25)Mg(p γ)(26)Al (19)F(p α)(16)O (13)C(α n)(16)O and (12)C(α γ)(16)O reactions Gamow window JUNA
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Evolution of the vortex structures and turbulent spots at the late-stage of transitional boundary layers 被引量:3
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作者 CHEN Lin TANG DengBin +1 位作者 LU Ping LIU ChaoQun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第5期986-990,共5页
The nonlinear evolution process of new vortex structures at the late-stage of the transition, including the 3-D spatial structure of barrel-shaped vortex and "dark spots" structure observed by experiment res... The nonlinear evolution process of new vortex structures at the late-stage of the transition, including the 3-D spatial structure of barrel-shaped vortex and "dark spots" structure observed by experiment research, has been confirmed by our computational results. The formation mechanisms of these structures have been explored. It is revealed that the new vortex structures, the ring-like vortex chain and induced disturbance velocities play a dominant role in the generation of turbulent spots. 展开更多
关键词 boundary layers TRANSITION barrel-shaped vortex turbulent spots direct numerical simulation
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Static flow on complete noncompact manifolds I:short-time existence and asymptotic expansions at conformal infinity 被引量:1
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作者 HU Xue SHI YuGuang 《Science China Mathematics》 SCIE 2012年第9期1883-1900,共18页
We study short-time existence of static flow on complete noncompact asymptotically static manifolds from the point of view that the stationary points of the evolution equations can be interpreted as static solutions o... We study short-time existence of static flow on complete noncompact asymptotically static manifolds from the point of view that the stationary points of the evolution equations can be interpreted as static solutions of the Einstein vacuum equations with negative cosmological constant.For a static vacuum(Mn,g,V),we also compute the asymptotic expansions of g and V at conformal infinity. 展开更多
关键词 static flow asymptotical static asymptotical hyperbolic
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Trajectory Attractors for Binary Fluid Mixtures in 3D 被引量:3
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作者 Ciprian G.GAL Maurizio GRASSELLI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第5期655-678,共24页
Two different models for the evolution of incompressible binary fluid mixtures in a three-dimensional bounded domain are considered.They consist of the 3D incompressible Navier-Stokes equations,subject to time-depende... Two different models for the evolution of incompressible binary fluid mixtures in a three-dimensional bounded domain are considered.They consist of the 3D incompressible Navier-Stokes equations,subject to time-dependent external forces and coupled with either a convective Allen-Cahn or Cahn-Hilliard equation.Such systems can be viewed as generalizations of the Navier-Stokes equations to two-phase fluids.Using the trajectory approach,the authors prove the existence of the trajectory attractor for both systems. 展开更多
关键词 Navier-Stokes equations Allen-Cahn equations Cahn-Hilliard equations Two-phase fluid flows Longtime behavior Trajectory attractors
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Fast jet proper motion discovered in a blazar at z=4.72
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作者 Yingkang Zhang Tao An Sándor Frey 《Science Bulletin》 SCIE EI CAS CSCD 2020年第7期525-530,M0003,共7页
High-resolution observations of high-redshift(z > 4) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model parameters.Due to the general... High-resolution observations of high-redshift(z > 4) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model parameters.Due to the general weakness of extremely distant objects and the apparently slow structural changes caused by cosmological time dilation, only a couple of high-redshift quasars(HRQs) have been studied with parsec-scale resolutions, and with limited number of observing epochs. Here we report on very long baseline interferometry(VLBI) observations of a high-redshift blazar J1430 + 4204(z=4.72) in the 8 GHz frequency band at five different epochs spanning 22 years. The source shows a compact core–jet structure with two jet components being identified within 3 milli-arcsecond(mas) scale. The long time span and multiple-epoch data allow for the kinematic studies of the jet components. That results in a jet proper motion of μ(J1) = 0.017 ± 0.002 mas a^-1 and μ(J2) = 0.156 ± 0.015 mas a^-1, respectively. For the fastest-moving outer jet component J2, the corresponding apparent transverse speed is (19.5 ± 1.9) c.The inferred bulk jet Lorentz factor C=14.6 ± 3.8 and viewing angle θ=2.2°± 1.6°indicate highly relativistic beaming. The Lorentz factor and apparent proper motion are the highest measured to date among the z > 4 jetted radio sources, while the jet kinematics is still consistent with the cosmological interpretation of quasar redshifts. 展开更多
关键词 NUCLEI HIGH-REDSHIFT Radio continuum QUASARS INDIVIDUAL J1430+4204
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Geomorphological inheritance for loess landform evolution in a severe soil erosion region of Loess Plateau of China based on digital elevation models 被引量:16
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作者 XIONG LiYang TANG GuoAn +3 位作者 YUAN BaoYin LU ZhongChen LI FaYuan ZHANG Lei 《Science China Earth Sciences》 SCIE EI CAS 2014年第8期1944-1952,共9页
The influence of pre-quaternary underlying terrain on the formation of loess landforms, i.e., the geomorphological inheritance issue, is a focus in studies of loess landforms. On the basis of multi-source information,... The influence of pre-quaternary underlying terrain on the formation of loess landforms, i.e., the geomorphological inheritance issue, is a focus in studies of loess landforms. On the basis of multi-source information, we used GIS spatial analysis methods to construct a simulated digital elevation model of a pre-quaternary paleotopographic surface in a severe soil erosion area of the Loess Plateau. To reveal the spatial relationship between underlying paleotopography and modern terrain, an XY scatter diagram, hypsometric curve, gradient and concavity of terrain profiles are used in the experiments. The experiments show that the altitude, gradient and concavity results have significant linear positive correlation between both terrains, which shows a relatively strong landform inheritance relationship, particularly in the intact and complete loess deposit areas. Despite the current surface appearing somewhat changed from the original shape of the underlying terrain under different erosion forces, we reveal that the modern terrain generally smoothes the topographic relief of underlying terrain in the loess deposition process. Our results deepen understanding of the characteristics of geomorphological inheritance in the formation and evolution of loess landforms. 展开更多
关键词 loess landform landform inheritance underlying paleotopography digital elevation model
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A New(γ_A,σ_B)-Matrix KP Hierarchy and Its Solutions
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作者 黄晔辉 姚玉芹 曾云波 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第4期515-522,共8页
A new(γA,σB)-matrix KP hierarchy with two time series γA and σB,which consists of γA-flow,σB-flow and mixed γA and σB-evolution equations of eigenfunctions,is proposed.The reduction and constrained flows of(... A new(γA,σB)-matrix KP hierarchy with two time series γA and σB,which consists of γA-flow,σB-flow and mixed γA and σB-evolution equations of eigenfunctions,is proposed.The reduction and constrained flows of(γA,σB)matrix KP hierarchy are studied.The dressing method is generalized to the(γA,σB)-matrix KP hierarchy and some solutions are presented. 展开更多
关键词 (γA σB)-matrix KP hierarchy Lax representation generalized dressing method SOLITON
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