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
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
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
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
Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three dif...Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three different types of impurities are generally available in the pharmaceutical’s product specification: organic impurities, inorganic impurities, and residual solvents. Residual solvents are organic volatile chemicals used or generated during the manufacturing of drug substances or drug products. Purpose: The aim of this study is to develop a cost-effective gas chromatographic method for the identification and quantification of some commonly used solvents—methanol, acetone, isopropyl alcohol (IPA), methylene chloride, ethyl acetate, tetrahydrofuran (THF), benzene, toluene, and pyridine—in pharmaceutical product manufacturing. This method will be able to identify and quantify the multiple solvents within a single gas chromatographic procedure. Method: A gas chromatography (GC) equipped with a headspace sampler and a flame ionization detector, and a column DB 624, 30-meter-long × 0.32-millimeter internal diameter, 1,8 μm-thick, Brand-Agilent was used to develop this method. The initial GC oven temperature was 40°C and held for 5 minutes. It was then increase to 80˚C at a rate of 2˚C per minute, followed by a further increase to 225˚C at a rate of 30˚C per minute, with a final hold at 225˚C for 10 minutes. Nitrogen was used as a carrier gas at a flow rate of 1.20 mL per minute. Dimethyl sulfoxide (DMSO) was selected as sample solvent. Results: The developed method is precise and specific. The percent RSD for the areas of six replicate injections of this gas chromatographic method was within 10.0 and the recovery result found within 80.0% to 120.0%.展开更多
Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other m...Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of approximation of the phase function of the RTE leads to a better precision in flux calculations. However, this approach may be limited to a certain order that has not been studied in this paper.展开更多
The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bon...The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods.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
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.
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.
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.
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Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three different types of impurities are generally available in the pharmaceutical’s product specification: organic impurities, inorganic impurities, and residual solvents. Residual solvents are organic volatile chemicals used or generated during the manufacturing of drug substances or drug products. Purpose: The aim of this study is to develop a cost-effective gas chromatographic method for the identification and quantification of some commonly used solvents—methanol, acetone, isopropyl alcohol (IPA), methylene chloride, ethyl acetate, tetrahydrofuran (THF), benzene, toluene, and pyridine—in pharmaceutical product manufacturing. This method will be able to identify and quantify the multiple solvents within a single gas chromatographic procedure. Method: A gas chromatography (GC) equipped with a headspace sampler and a flame ionization detector, and a column DB 624, 30-meter-long × 0.32-millimeter internal diameter, 1,8 μm-thick, Brand-Agilent was used to develop this method. The initial GC oven temperature was 40°C and held for 5 minutes. It was then increase to 80˚C at a rate of 2˚C per minute, followed by a further increase to 225˚C at a rate of 30˚C per minute, with a final hold at 225˚C for 10 minutes. Nitrogen was used as a carrier gas at a flow rate of 1.20 mL per minute. Dimethyl sulfoxide (DMSO) was selected as sample solvent. Results: The developed method is precise and specific. The percent RSD for the areas of six replicate injections of this gas chromatographic method was within 10.0 and the recovery result found within 80.0% to 120.0%.
文摘Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta Function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(F-TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of approximation of the phase function of the RTE leads to a better precision in flux calculations. However, this approach may be limited to a certain order that has not been studied in this paper.
文摘The systematic method for constructing Lewis representations is a method for representing chemical bonds between atoms in a molecule. It uses symbols to represent the valence electrons of the atoms involved in the bond. Using a number of rules in a defined order, it is often better suited to complicated cases than the Lewis representation of atoms. This method allows us to determine the formal charge and oxidation number of each atom in the edifice more efficiently than other methods.
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.