Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the resul...Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the results should be given together when the measurement result is given. Nowadays most researches on straightness focus on error calculation and only several research projects evaluate the measurement uncertainty based on "The Guide to the Expression of Uncertainty in Measurement(GUM)". In order to compute spatial straightness error(SSE) accurately and rapidly and overcome the limitations of GUM, a quasi particle swarm optimization(QPSO) is proposed to solve the minimum zone SSE and Monte Carlo Method(MCM) is developed to estimate the measurement uncertainty. The mathematical model of minimum zone SSE is formulated. In QPSO quasi-random sequences are applied to the generation of the initial position and velocity of particles and their velocities are modified by the constriction factor approach. The flow of measurement uncertainty evaluation based on MCM is proposed, where the heart is repeatedly sampling from the probability density function(PDF) for every input quantity and evaluating the model in each case. The minimum zone SSE of a shaft measured on a Coordinate Measuring Machine(CMM) is calculated by QPSO and the measurement uncertainty is evaluated by MCM on the basis of analyzing the uncertainty contributors. The results show that the uncertainty directly influences the product judgment result. Therefore it is scientific and reasonable to consider the influence of the uncertainty in judging whether the parts are accepted or rejected, especially for those located in the uncertainty zone. The proposed method is especially suitable when the PDF of the measurand cannot adequately be approximated by a Gaussian distribution or a scaled and shifted t-distribution and the measurement model is non-linear.展开更多
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
UML Diagrams are considered as a main component in requirement engineering process and these become an industry standard in many organizations. UML diagrams are useful to show an interaction, behavior and structure of...UML Diagrams are considered as a main component in requirement engineering process and these become an industry standard in many organizations. UML diagrams are useful to show an interaction, behavior and structure of the system. Similarly, in requirement engineering, formal specification methods are also being used in crucial systems where precise information is required. It is necessary to integrate System Models with such formal methods to overcome the requirements errors i.e. contradiction, ambiguities, vagueness, incompleteness and mixed values of abstraction. Our objective is to integrate the Formal Specification Language (Z) with UML Sequence diagram, as sequence diagram is an interaction diagram which shows the interaction and proper sequence of components (Methods, procedures etc.) of the system. In this paper, we focus on components of UML Sequence diagram and then implement these components in formal specification language Z. And the results of this research papers are complete integrated components of Sequence diagram with Z schemas, which are verified by using tools and model based testing technique of Formal Specifications. Results can be more improved by integrating remaining components of Sequence and other UML diagrams into Formal Specification Language.展开更多
The FIPA specification of MAS (multi agent system)is accepted by most of the applications of MAS in the world, and has been used in many projects. This paper draws an Abstract architecture from the FIPA based MAS, and...The FIPA specification of MAS (multi agent system)is accepted by most of the applications of MAS in the world, and has been used in many projects. This paper draws an Abstract architecture from the FIPA based MAS, and gives formalization about it.展开更多
The lack of existing solutions makes it really hard to understand formal specification languages since the application domain for representations is useful for the purpose of carrying out certain software engineering ...The lack of existing solutions makes it really hard to understand formal specification languages since the application domain for representations is useful for the purpose of carrying out certain software engineering operations such as slicing and the computation of program metrics.A Z specification dependence graph is presented in this letter. It draws on the strengths of a range of earlier works and adapts them, if necessary, to the Z language.展开更多
In this paper,w e provide a novel scheme to solve the motion planning problem of multi-agent systems under high-level task specifications.First,linear temporal logic is applied to express the global task specification...In this paper,w e provide a novel scheme to solve the motion planning problem of multi-agent systems under high-level task specifications.First,linear temporal logic is applied to express the global task specification.Then an efficient and decentralized algorithm is proposed to decom pose it into local tasks.M oreover,w e use control barrier function to synthesize the local controller for each agent under the linear temporal logic motion plan with safety constraint.Finally,simulation results show the effectiveness and efficiency of our proposed scheme.展开更多
Specification language is used to provide enough information for the model of the cryptographic protocol. This paper first extends strand space model to dynamic strand model, and then a formal specification language f...Specification language is used to provide enough information for the model of the cryptographic protocol. This paper first extends strand space model to dynamic strand model, and then a formal specification language for this model is defined by using BNF grammar. Compared with those in literatures, it is simpler because of only concerning the algebraic properties of cryptographic protocols.展开更多
This paper proposes a formal method which is used to model and analyze network devices such as touters. It is based on an algebraic process called “ACSR-VP”, which enhances the original CCS algebraic process by inco...This paper proposes a formal method which is used to model and analyze network devices such as touters. It is based on an algebraic process called “ACSR-VP”, which enhances the original CCS algebraic process by incorporating the notions of time, resource requirements, dynamic prioritization, and synchronization. Therefore, although there are many formal methods to analyze the timed concurrency system, ACSR-VP, due to its prominent features, is best fit for analysis of a resource bounded real-time system. This paper extends ACSR-VP to EACSR-VP, which is more adaptive to the features of network devices and specializes in analyzing this kind of embedded system. EACSR-VP adds the notion of n-way communication which allows more than two processes to participate in synchronization. It also enhances value-passing capabilities which make for more flexible specifications. Finally, specifications, verification and analysis methods with EACSR-VP are introduced by a case study of router with multiple input queues.展开更多
Linear temporal logic(LTL)is an intuitive and expressive language to specify complex control tasks,and how to design an efficient control strategy for LTL specification is still a challenge.In this paper,we implement ...Linear temporal logic(LTL)is an intuitive and expressive language to specify complex control tasks,and how to design an efficient control strategy for LTL specification is still a challenge.In this paper,we implement the dynamic quantization technique to propose a novel hierarchical control strategy for nonlinear control systems under LTL specifications.Based on the regions of interest involved in the LTL formula,an accepting path is derived first to provide a high-level solution for the controller synthesis problem.Second,we develop a dynamic quantization based approach to verify the realization of the accepting path.The realization verification results in the necessity of the controller design and a sequence of quantization regions for the controller design.Third,the techniques of dynamic quantization and abstraction-based control are combined together to establish the local-to-global control strategy.Both abstraction construction and controller design are local and dynamic,thereby resulting in the potential reduction of the computational complexity.Since each quantization region can be considered locally and individually,the proposed hierarchical mechanism is more efficient and can solve much larger problems than many existing methods.Finally,the proposed control strategy is illustrated via two examples from the path planning and tracking problems of mobile robots.展开更多
Specifying software requirements is an important, complicated and error prone task. It involves the collaboration of several people specifying requirements that are gathered through several stakeholders. During this p...Specifying software requirements is an important, complicated and error prone task. It involves the collaboration of several people specifying requirements that are gathered through several stakeholders. During this process, developers working in parallel introduce and make modifications to requirements until reaching a specification that satisfies the stakeholders’ requirements. Merge conflicts are inevitable when integrating the modifications made by different developers to a shared specification. Thus, detecting and resolving these conflicts is critical to ensure a consistent resulting specification. A conflicts detection approach for merging Object-Oriented formal specifications is proposed in this paper. Conflicts are classified, formally defined and detected based on the results of a proposed differencing algorithm. The proposed approach has been empirically evaluated, and the experimental results are discussed in this paper.展开更多
The quality of mischmetal wire and rod and the method of adding rare earth into steel are quite important for making high quality steel. This paper proposes a quality specification of wire and rod as well as related a...The quality of mischmetal wire and rod and the method of adding rare earth into steel are quite important for making high quality steel. This paper proposes a quality specification of wire and rod as well as related adding method. The paper also provides principles for selecting raw material and adding method.展开更多
目的探讨病种成本可视化分析系统的设计与构建。方法选择Power BI作为可视化分析工具。采集病种成本相关数据,导入Power BI并建立数据模型,编写度量值。采用Power BI Desktop设计可视化界面,对分析结果进行可视化展示,构建完整的病种成...目的探讨病种成本可视化分析系统的设计与构建。方法选择Power BI作为可视化分析工具。采集病种成本相关数据,导入Power BI并建立数据模型,编写度量值。采用Power BI Desktop设计可视化界面,对分析结果进行可视化展示,构建完整的病种成本可视化分析系统。结果可视化分析系统从总体概况、科室成本分析、DRG成本分析、DIP成本分析及病种成本分析五个角度进行分析展示,展示内容丰富,具有良好的洞察与分析效果。结论本研究应用Power BI快速实现了病种成本可视化分析系统的构建。病种成本可视化分析系统可为精细化管理和决策提供有效支持。展开更多
Abstract Separation kernels are fundamental software of safety and security-critical systems, which provide their hosted applications with spatial and temporal separation as well as controlled information flows among ...Abstract Separation kernels are fundamental software of safety and security-critical systems, which provide their hosted applications with spatial and temporal separation as well as controlled information flows among partitions. The application of separation kernels in critical domain demands the correctness of the kernel by formal verification. To the best of our knowledge, there is no survey paper on this topic. This paper presents an overview of formal specification and verification of separation kernels. We first present the back- ground including the concept of separation kernel and the comparisons among different kernels. Then, we survey the state of the art on this topic since 2000. Finally, we summa- rize research work by detailed comparison and discussion.展开更多
基金supported by National Natural Science Foundation of China (Grant No. 51075198)Jiangsu Provincial Natural Science Foundation of China (Grant No. BK2010479)+2 种基金Innovation Research of Nanjing Institute of Technology, China (Grant No. CKJ20100008)Jiangsu Provincial Foundation of 333 Talents Engineering of ChinaJiangsu Provincial Foundation of Six Talented Peak of China
文摘Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product speeifieation(GPS) requires the measurement uncertainty characterizing the reliability of the results should be given together when the measurement result is given. Nowadays most researches on straightness focus on error calculation and only several research projects evaluate the measurement uncertainty based on "The Guide to the Expression of Uncertainty in Measurement(GUM)". In order to compute spatial straightness error(SSE) accurately and rapidly and overcome the limitations of GUM, a quasi particle swarm optimization(QPSO) is proposed to solve the minimum zone SSE and Monte Carlo Method(MCM) is developed to estimate the measurement uncertainty. The mathematical model of minimum zone SSE is formulated. In QPSO quasi-random sequences are applied to the generation of the initial position and velocity of particles and their velocities are modified by the constriction factor approach. The flow of measurement uncertainty evaluation based on MCM is proposed, where the heart is repeatedly sampling from the probability density function(PDF) for every input quantity and evaluating the model in each case. The minimum zone SSE of a shaft measured on a Coordinate Measuring Machine(CMM) is calculated by QPSO and the measurement uncertainty is evaluated by MCM on the basis of analyzing the uncertainty contributors. The results show that the uncertainty directly influences the product judgment result. Therefore it is scientific and reasonable to consider the influence of the uncertainty in judging whether the parts are accepted or rejected, especially for those located in the uncertainty zone. The proposed method is especially suitable when the PDF of the measurand cannot adequately be approximated by a Gaussian distribution or a scaled and shifted t-distribution and the measurement model is non-linear.
基金Supported by Natural Science Foundation of Hubei Province (98J0 75 ) Ziqiang Technical Innovation Foundation ofWuhan Universi
文摘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.
文摘UML Diagrams are considered as a main component in requirement engineering process and these become an industry standard in many organizations. UML diagrams are useful to show an interaction, behavior and structure of the system. Similarly, in requirement engineering, formal specification methods are also being used in crucial systems where precise information is required. It is necessary to integrate System Models with such formal methods to overcome the requirements errors i.e. contradiction, ambiguities, vagueness, incompleteness and mixed values of abstraction. Our objective is to integrate the Formal Specification Language (Z) with UML Sequence diagram, as sequence diagram is an interaction diagram which shows the interaction and proper sequence of components (Methods, procedures etc.) of the system. In this paper, we focus on components of UML Sequence diagram and then implement these components in formal specification language Z. And the results of this research papers are complete integrated components of Sequence diagram with Z schemas, which are verified by using tools and model based testing technique of Formal Specifications. Results can be more improved by integrating remaining components of Sequence and other UML diagrams into Formal Specification Language.
文摘The FIPA specification of MAS (multi agent system)is accepted by most of the applications of MAS in the world, and has been used in many projects. This paper draws an Abstract architecture from the FIPA based MAS, and gives formalization about it.
文摘The lack of existing solutions makes it really hard to understand formal specification languages since the application domain for representations is useful for the purpose of carrying out certain software engineering operations such as slicing and the computation of program metrics.A Z specification dependence graph is presented in this letter. It draws on the strengths of a range of earlier works and adapts them, if necessary, to the Z language.
基金This work was partially supported by the National Natural Science Foundation of China(No.51475334)the National Key Research and Development Program of Science and Technology of China(No.2018YFB1305304)the Shanghai Science and Technology Pilot Project(No.19511132100).
文摘In this paper,w e provide a novel scheme to solve the motion planning problem of multi-agent systems under high-level task specifications.First,linear temporal logic is applied to express the global task specification.Then an efficient and decentralized algorithm is proposed to decom pose it into local tasks.M oreover,w e use control barrier function to synthesize the local controller for each agent under the linear temporal logic motion plan with safety constraint.Finally,simulation results show the effectiveness and efficiency of our proposed scheme.
文摘Specification language is used to provide enough information for the model of the cryptographic protocol. This paper first extends strand space model to dynamic strand model, and then a formal specification language for this model is defined by using BNF grammar. Compared with those in literatures, it is simpler because of only concerning the algebraic properties of cryptographic protocols.
文摘This paper proposes a formal method which is used to model and analyze network devices such as touters. It is based on an algebraic process called “ACSR-VP”, which enhances the original CCS algebraic process by incorporating the notions of time, resource requirements, dynamic prioritization, and synchronization. Therefore, although there are many formal methods to analyze the timed concurrency system, ACSR-VP, due to its prominent features, is best fit for analysis of a resource bounded real-time system. This paper extends ACSR-VP to EACSR-VP, which is more adaptive to the features of network devices and specializes in analyzing this kind of embedded system. EACSR-VP adds the notion of n-way communication which allows more than two processes to participate in synchronization. It also enhances value-passing capabilities which make for more flexible specifications. Finally, specifications, verification and analysis methods with EACSR-VP are introduced by a case study of router with multiple input queues.
基金supported by the Fundamental Research Funds for the Central Universities(DUT22RT(3)090)the National Natural Science Foundation of China(61890920,61890921,62122016,08120003)Liaoning Science and Technology Program(2023JH2/101700361).
文摘Linear temporal logic(LTL)is an intuitive and expressive language to specify complex control tasks,and how to design an efficient control strategy for LTL specification is still a challenge.In this paper,we implement the dynamic quantization technique to propose a novel hierarchical control strategy for nonlinear control systems under LTL specifications.Based on the regions of interest involved in the LTL formula,an accepting path is derived first to provide a high-level solution for the controller synthesis problem.Second,we develop a dynamic quantization based approach to verify the realization of the accepting path.The realization verification results in the necessity of the controller design and a sequence of quantization regions for the controller design.Third,the techniques of dynamic quantization and abstraction-based control are combined together to establish the local-to-global control strategy.Both abstraction construction and controller design are local and dynamic,thereby resulting in the potential reduction of the computational complexity.Since each quantization region can be considered locally and individually,the proposed hierarchical mechanism is more efficient and can solve much larger problems than many existing methods.Finally,the proposed control strategy is illustrated via two examples from the path planning and tracking problems of mobile robots.
文摘Specifying software requirements is an important, complicated and error prone task. It involves the collaboration of several people specifying requirements that are gathered through several stakeholders. During this process, developers working in parallel introduce and make modifications to requirements until reaching a specification that satisfies the stakeholders’ requirements. Merge conflicts are inevitable when integrating the modifications made by different developers to a shared specification. Thus, detecting and resolving these conflicts is critical to ensure a consistent resulting specification. A conflicts detection approach for merging Object-Oriented formal specifications is proposed in this paper. Conflicts are classified, formally defined and detected based on the results of a proposed differencing algorithm. The proposed approach has been empirically evaluated, and the experimental results are discussed in this paper.
文摘The quality of mischmetal wire and rod and the method of adding rare earth into steel are quite important for making high quality steel. This paper proposes a quality specification of wire and rod as well as related adding method. The paper also provides principles for selecting raw material and adding method.
文摘Abstract Separation kernels are fundamental software of safety and security-critical systems, which provide their hosted applications with spatial and temporal separation as well as controlled information flows among partitions. The application of separation kernels in critical domain demands the correctness of the kernel by formal verification. To the best of our knowledge, there is no survey paper on this topic. This paper presents an overview of formal specification and verification of separation kernels. We first present the back- ground including the concept of separation kernel and the comparisons among different kernels. Then, we survey the state of the art on this topic since 2000. Finally, we summa- rize research work by detailed comparison and discussion.