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Development of the Object-Oriented Reservoir Description Systems in China
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作者 Zhang Xuewen and Liu Yu(Research Institute of petroleum Exploration and Development) 《China Oil & Gas》 CAS 1998年第3期161-162,共2页
关键词 object-oriented SOFTWARE DEVELOPMENT RESERVOIR description
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NDVI-Based Lacunarity Texture for Improving Identification of Torreya Using Object-Oriented Method 被引量:4
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作者 HAN Ning WU Jing +2 位作者 Amir Reza Shah Tahmassebi XU Hong-wei WANG Ke 《Agricultural Sciences in China》 CAS CSCD 2011年第9期1431-1444,共14页
Normalized Difference Vegetation Index (NDVI) is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the... Normalized Difference Vegetation Index (NDVI) is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the vegetation landscapes, we proposed the lacunarity texture derived from NDVI to characterize the spatial patterns of vegetation landscapes concerning the "gappiness" or "emptiness" characteristics. The NDVI-based lacunarity texture was incorporated into object-oriented classification for improving the identification of vegetation categories, especially Torreya which was the targeted tree species in the present research. A three-level hierarchical network of image objects was defined and the proposed texture was integrated as potential sources of information in the rules base. A knowledge base of rules created by classifier C5.0 indicated that the texture could potentially be applied in object-oriented classification. It was found that the addition of such texture improved the identification of every vegetation category. The results demonstrated that the texture could characterize the spatial patterns of vegetation structures, which could be a promising approach for vegetation identification. 展开更多
关键词 Torreya NDVI LACUNARITY class hierarchy object-oriented method decision tree spatial pattern
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A Hybrid Formal Description Method Based on FSM,CSP and ADT for Communication Protocol
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作者 Li Layman(Wuhan Transportation Universityl 430063, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期29-38,共10页
Since communication protocol deals with complex issues related to distribution such as communication, concurrency and synchronization, their development needs to be traced by using sophisticated formal description met... Since communication protocol deals with complex issues related to distribution such as communication, concurrency and synchronization, their development needs to be traced by using sophisticated formal description methods. This paper presents a new hybrid formal method for communication protocol specification. In this method, finite state machine (FSM), communication sequential process (CSP) and abstract data type (ADT) are mixed and the best features of these approaches are offered. In this paper, the main formal description techniques (FDT) for protocol engineering are brieny introduced and a hybrid formal description method based on the FSM, CSP and ADT for communication protocol is described. Finally, this paper presents the formal specification of an example protocol for LAN by using the proposed hybrid formal method. The results of studies show that the hybrid formal description method for communication protocol is an available and effective approach. 展开更多
关键词 Communication protocol Formal description techniques Protocol engineering Hybrid formal method
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A Study on Description Methods of Sediment Transport Modulus in Small Watersheds
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作者 Zhiguang LI Liyi ZHAO 《Meteorological and Environmental Research》 CAS 2021年第5期50-54,共5页
[Objective]This study aimed to clear the advantages,disadvantages and applicability of various analysis methods to assess sediment transport modulus in small watersheds using the multi-year observation data. [Method]F... [Objective]This study aimed to clear the advantages,disadvantages and applicability of various analysis methods to assess sediment transport modulus in small watersheds using the multi-year observation data. [Method]Four methods,including the statistical eigenvalues,depolarized arithmetic mean,frequency of erosion intensity and box-whisker plots were applied into calculation of sediment transport modulus in four small watersheds,and then the results of the methods were compared to to filter a method with the widest applicability and scientific validity. [Result] The statistical arithmetic mean and median could hardly represent the concentration and general level of multi-year sediment transport modulus. Although the depolarized arithmetic mean had the tendency of reflecting the general level of data,it lost the extreme value and its information for making decision. The frequency of erosion intensity grade reflected the distribution of data in intensity classification. Box-whisker plot could show the concentration,dispersion and the number of abnormal data. [Conclusion] Multiple methods can be combined to comprehensively and objectively characterize the multi-year sand transport modulus due to their advantages and disadvantages. Additionally,box-whisker plot has good objectivity and applicability in displaying the multi-year data of small watershed. 展开更多
关键词 Small watershed Sediment transport modulus General situation of many years description methods Multi-year average Box-whisker plot
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A Brief Description of Audio-Lingual Method and Discussion of its Advantages and Disadvantages vis-a-vis the English Language Teaching Situation in Chinese Middle Schools
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作者 Luo Ling 《黄山学院学报》 1998年第1期83-84,共2页
With the development of reform and open policy, foreign languages become more and moreuseful. And how to teach a foreign language is an important matter. A lot of methods of teaching foreign languages have been develo... With the development of reform and open policy, foreign languages become more and moreuseful. And how to teach a foreign language is an important matter. A lot of methods of teaching foreign languages have been developed. There’re grammar-trans-lation method, direct method, audio-lingual method, communicative method, etc. In this paper I in- 展开更多
关键词 A Brief description of Audio-Lingual method and Discussion of its Advantages and Disadvantages vis-a-vis the English Language Teaching Situation in Chinese Middle Schools
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Shrek:a dynamic object-oriented programming language 被引量:1
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作者 曹璟 徐宝文 周毓明 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期31-35,共5页
From a perspective of theoretical study, there are some faults in the models of the existing object-oriented programming languages. For example, C# does not support metaclasses, the primitive types of Java and C# are ... From a perspective of theoretical study, there are some faults in the models of the existing object-oriented programming languages. For example, C# does not support metaclasses, the primitive types of Java and C# are not objects, etc. So, this paper designs a programming language, Shrek, which integrates many language features and constructions in a compact and consistent model. The Shrek language is a class-based purely object-oriented language. It has a dynamical strong type system, and adopts a single-inheritance mechanism with Mixin as its complement. It has a consistent class instantiation and inheritance structure, and the ability of intercessive structural computational reflection, which enables it to support safe metaclass programming. It also supports multi-thread programming and automatic garbage collection, and enforces its expressive power by adopting a native method mechanism. The prototype system of the Shrek language is implemented and anticipated design goals are achieved. 展开更多
关键词 dynamic typing metaclass programming computational reflection native method object-oriented programming language
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Object-oriented Urban Dynamic Monitoring——A Case Study of Haidian District of Beijing 被引量:9
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作者 An Kai Zhang Jinshui Xiao Yu 《Chinese Geographical Science》 SCIE CSCD 2007年第3期236-242,共7页
It is crucial to conduct the land use/cover research to obtain the global change information.Urban area is one of the most sensitive areas in land use/cover change.Therefore land use/cover change in urban areas is ver... It is crucial to conduct the land use/cover research to obtain the global change information.Urban area is one of the most sensitive areas in land use/cover change.Therefore land use/cover change in urban areas is very im-portant in global change.It is vital to incorporate the information of urban land use/cover change into the process of decision-making about urban area development.In this paper,a new urban change detection approach,urban dynamic monitoring based on objects,is introduced.This approach includes four steps:1)producing multi-scale objects from multi-temporal remotely sensed images with spectrum,texture and context information;2)extracting possible changed objects adopting object-oriented classification;3)obtaining shared objects as the basic units for urban change detection;4)determining the threshold to segment the changed objects from the possible changed objects using Otsu method.In this paper,the object-based approach was applied to detecting the urban expansion in Haidian District,Beijing,China with two Landsat Thematic Mapper(TM)data in 1997 and 2004.The results indicated that the overall accuracy was about 84.83%,and Kappa about 0.785.Compared with other conventional approaches,the object-based approach was advantageous in reducing the error accumulation of image classification of each datum and in independence to the radiometric correction and image registration accuracy. 展开更多
关键词 urban change detection object-oriented method remote sensing land use/cover Otsu method
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The third-order asymptotic solutions in the Lagrangian description for interfacial internal waves in a three layer fluid system
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作者 Baole Zhang Jifeng Cui +1 位作者 Xiaogang Chen Wenyu Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期1-13,共13页
In this paper,we discuss the interfacial internal waves with a rigid boundary in a three-layer fluid system,where the density of the upper layer fluid is smaller than that of the lower layer.With the Lagrangian matchi... In this paper,we discuss the interfacial internal waves with a rigid boundary in a three-layer fluid system,where the density of the upper layer fluid is smaller than that of the lower layer.With the Lagrangian matching conditions at the interfaces,the first-order solutions,the second-order solutions and the third-order asymptotic solutions for the interfacial internal waves are obtained in the Lagrangian description using the perturbation method,and the mass transport velocity,the wave frequency,the mean level and the particle trajectory are also given.The results show that the discontinuities across the interfaces appear for the mass transport velocity,wave frequency and mean level,but we find that these discontinuities may disappear if the water depth ratio and the density ratio of the three layer fluids satisfy certain conditions. 展开更多
关键词 INTERFACIAL internal waves LAGRANGIAN description particle TRAJECTORY PERTURBATION method
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OBJECT-ORIENTED FINITE ELEMENT ANALYSIS AND PROGRAMMING IN VC++
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作者 MA Yong-qi(马永其) +1 位作者 FENG Wei(冯伟) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1437-1443,共7页
The design of finite element analysis program using object-oriented programming (OOP) techniques is presented. The objects, classes and the subclasses used in the programming are explained. The system of classes libra... The design of finite element analysis program using object-oriented programming (OOP) techniques is presented. The objects, classes and the subclasses used in the programming are explained. The system of classes library of finite element analysis program and Windows-type Graphical User Interfaces by VC + + and its MFC are developed. The reliability, reusability and extensibility of program are enhanced. It is a reference to develop the large-scale, versatile and powerful systems of object-oriented finite element software. 展开更多
关键词 object-oriented programming finite element method PROGRAM design VC+ +
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Finite Element Structural Analysis UsingObject-Oriented Techniques
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作者 张冬泉 姜继海 +1 位作者 梁迎春 孙靖民 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期67-71,共5页
This paper describes the object-oriented implementational method of finite element structural analysis, gives the basic concepts of the object-oriented method and objectoriented programming, develops a complete class ... This paper describes the object-oriented implementational method of finite element structural analysis, gives the basic concepts of the object-oriented method and objectoriented programming, develops a complete class hierarchy structure of object-oriented finite element structural analysis, and gives a part C+ + code description. 展开更多
关键词 object-oriented method(OOM) object-oriented programming(OOP) finite element analysis(FEA) class HIERARCHY
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An AI Embedded Object-Oriented Approach for Formulating Computable General Equilibrium
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作者 Li Tong (Department of Automatic Control Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China) Chen Shuheng (Department of Economics, National Chengchi University, Taipei, 11623) Feng Shan (Department of Automatic Control 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第1期14-21,共8页
This paper proposes and illustrates an AI embedded object-oriented methodology to formulate the computable general equilibrium (CGE) models. In this framework, a CGE model is viewed as a collection of objects embedd... This paper proposes and illustrates an AI embedded object-oriented methodology to formulate the computable general equilibrium (CGE) models. In this framework, a CGE model is viewed as a collection of objects embedded AI or namely agents in computer world, corresponding to economic agents and entities in real world, such as government, households, markets and so on. A frame representation of major objects in CGE model is used for trade and environment. Embedded Al object-oriented approach (or software agent) is used in the CGE model representation can able to narrow the gap among the semantic representation, formal CGE (mathematical) representation and computer and algorithm representation, and to improve CGE in understanding and maintenance etc. In such a system, constructing a CGE model to appear an intuitive process rather than an abstract process. This intuitive process needs more understanding of the substance of economics and the logic underlying the problem rather than mathematical notation. 展开更多
关键词 Computable general equilibrium Artificial intelligence object-oriented method Agents.
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Object-oriented software tools for parallel PDE solvers
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作者 Michael Thune(Uppsala University, Dept. of Scientific Computing, Box 12O, S-751 04, Uppsala, Sweden.E-mail: ndchael@tdb.uu.se) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期420-429,共10页
An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writ... An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writing programs to be executed on MIMD computers with distributed memory. Difference methods on composite, structured grids are supported. Most of the Cogito classes have been implemented in Fortran 77, in such a way that the object-oriented design is visible. With respect to parallel performance, these tools yield code that is comparable to parallel solvers written in plain Fortran 77. The resulting programs are can be executed without modification on a large number of multicomputer platforms, and also on serial computers. The uppermost level of abstraction in Cogito concerns the problem of decoupling the numerical method from the PDE problem. The validity of these tools has been preliminarily demonstrated with a C++ implementation for one-dimensional problems. 展开更多
关键词 object-oriented software tool parallel computer PDE composite grid difference method
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Concurrent Object-Oriented Programming Based on MPI
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作者 鲁宏伟 裴晓黎 +1 位作者 汪厚祥 肖永玲 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期295-300,共6页
Object-oriented model possesses inherent concurrency. Integration of concurrency and object-orientation is a promising new field. MPI is a message-passing standard and has been adopted by more and more systems. This p... Object-oriented model possesses inherent concurrency. Integration of concurrency and object-orientation is a promising new field. MPI is a message-passing standard and has been adopted by more and more systems. This paper proposes a novel approach to realize concurrent object-oriented programming based on Message-passing interface(MPI) in which future method communication is adopted between concurrent objects. A state behavior set is proposed to solve inheritance anomaly, and a bounded buffer is taken as an example to illustrate this proposal. The definition of ParaMPI class, which is the most important class in the concurrent class library, and implementation issues are briefly described. 展开更多
关键词 message-passing interface object-oriented the future method inheritance anomaly concurrent class library.
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Object-Oriented Modeling of the Variation of Acceleration and Deceleration Characteristics in Relation to Speed Bands for Railway Vehicles
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作者 Hyun-Soo Jeong Jong-Young Park Hanmin Lee 《Energy and Power Engineering》 2023年第8期277-290,共14页
Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this stu... Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this study, the authors propose a method to efficiently simulate the kinematic characteristics of railroad vehicles depending on their speed zone. They utilized the function overloading function supported by a programming language and applied the fourth-order Lunge-Kutta method for dynamic simulation. By constructing an object model, the authors calculated vehicle characteristics and TPS and compared them with actual values, verifying that the developed model represents the real-life vehicle characteristics accurately. The study highlights potential improvements in automated driving and energy consumption optimization in the railway industry. 展开更多
关键词 Railway Vehicle ATO Lunge-Kutta method object-oriented Model Function Overloading
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Object-Oriented Finite Element Analysis of Metal Working Processes
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作者 Surendra Kumar 《Journal of Software Engineering and Applications》 2010年第6期572-579,共8页
Recently an object-oriented approach has been applied in the fields of finite element analysis with a view to treating the various complexities within these. It has been demonstrated that finite element software desig... Recently an object-oriented approach has been applied in the fields of finite element analysis with a view to treating the various complexities within these. It has been demonstrated that finite element software designed using an object-oriented approach can be significantly more robust than traditional codes. This paper describes a special kind of implementation of object-oriented programming which is rather hybrid in nature, in the development of a finite element code for engineering analysis of metal working problems using C++, and discusses the advantages of this approach. 展开更多
关键词 FINITE Element method Data ABSTRACTION Techniques object-oriented PROGRAMMING C++ PROGRAMMING Language METAL Working
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基于新工科的画法几何与机械制图教学创新与实践
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作者 万志华 钟文 余群 《实验室研究与探索》 北大核心 2026年第3期192-197,209,共7页
新工科建设对“画法几何与机械制图”课程提出新要求,需强化三维设计能力、融合数字化建模工具、突出工程规范应用,并结合创新实践,以培养空间思维与解决复杂工程问题的能力。针对该课程教学中学生运用图学知识解决实践问题能力不足、... 新工科建设对“画法几何与机械制图”课程提出新要求,需强化三维设计能力、融合数字化建模工具、突出工程规范应用,并结合创新实践,以培养空间思维与解决复杂工程问题的能力。针对该课程教学中学生运用图学知识解决实践问题能力不足、空间想象与创新思维能力提升困难、机械制图国家标准意识培育不易等问题,本文从课程内容重构、课程资源建设、教学方法改革及教学评价改革等方面开展教学创新与改革实践,构建了以三维实体为驱动的“三教融合”制图教学新模式,并取得阶段性教学成效,期望为图学类课程教学改革提供参考。 展开更多
关键词 三教融合 三维实体 新工科 画法几何与机械制图 教学创新
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The least square particle finite element method for simulating large amplitude sloshing flows 被引量:2
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作者 Bo Tang Junfeng Li Tianshu Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第3期317-323,共7页
Large amplitude sloshing in tanks is simulated by the least square particle finite element method (LSPFEM) in this paper. The least square finite element method (LSFEM) is employed to spatially discrete the Navier... Large amplitude sloshing in tanks is simulated by the least square particle finite element method (LSPFEM) in this paper. The least square finite element method (LSFEM) is employed to spatially discrete the Navier-Stokes equations, and to avoid the stabilization issues due to the incompressibility condition for equal-order interpolation of the velocity and the pressure, as usually used in Galerkin method to satisfy the well-known LBB condition. The LSPFEM also uses the Lagrangian description to model the motion of nodes (particles). A mesh which connects these nodes is constructed by a triangulation algorithm to avoid the mesh distortion. A quasi a-shapes algorithm is used to identify the free surface boundary. The nodes are viewed as particles which can freely move and even separate from the main fluid domain. Finally this method is used to study the large amplitude sloshing evolution in two dimensional tanks. The results are compared with those obtained by Flow-3d with good agreement. 展开更多
关键词 Incompressible fluid Least square finiteelement method Lagrangian description Boundaryrecognition COLLAPSE IMPACT
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A Shortcut for Extricating System Development from Predicament-by Means of Object-oriented Methods
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作者 潘启澍 安实 +1 位作者 王福胜 张宝祥 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期92-95,共4页
Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system develo... Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system development from the predicament. 展开更多
关键词 ss: object-oriented method (o-o method) RELATIONAL SYSTEM SYSTEM developing SYSTEM design
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Viscous flow with free surface motion by least square finite element method
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作者 汤波 李俊峰 王天舒 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第7期943-952,共10页
A method for simulation of free surface problems is presented. Based on the viscous incompressible Navier-Stokes equations, space discretization of the flow is obtained by the least square finite element method. The t... A method for simulation of free surface problems is presented. Based on the viscous incompressible Navier-Stokes equations, space discretization of the flow is obtained by the least square finite element method. The time evolution is obtained by the finite difference method. Lagrangian description is used to track the free surface. The results are compared with the experimental dam break results, including water collapse in a 2D rectangular section and in a 3D cylinder section. A good agreement is achieved for the distance of surge front as well as the height of the residual column. 展开更多
关键词 incompressible viscous fluid Lagrangian description least square finite element method dam break experiment
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New Refinement Relations of Z Specifications for Multiple Viewpoints Oriented Requirements Method
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作者 He Yan xiang, Song Qiang, Huang Qian School of Computer, State Key Laboratory of Software Engineering Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期304-312,共9页
In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate ... In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate or correct when considering specifications that have temporal relationships of operations. The concept of temporal state variables is introduced into Z. Then new implementation relations are defined and new refinement relations are deduced, mainly for temporal state variables to process temporal relationships of operations. We use state transition systems to abstract the temporal state transitions. A simple example is used to show the procedures of MVORM. Finally some directions of further work are forwarded. 展开更多
关键词 temporal state variable formal description language state transition system implementation relation refinement relation multiple viewpoints oriented requirements method
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