Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve...Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit.展开更多
Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and elec...Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and electronic contract signing,ensuring the reliability and security of network transactions.In order to address the limitations of current research methods and enhance the analytical capabilities for fair exchange protocols,this paper proposes a formal model for analyzing such protocols.The proposed model begins with a thorough analysis of fair exchange protocols,followed by the formal definition of fairness.This definition accurately captures the inherent requirements of fair exchange protocols.Building upon event logic,the model incorporates the time factor into predicates and introduces knowledge set axioms.This enhancement empowers the improved logic to effectively describe the state and knowledge of protocol participants at different time points,facilitating reasoning about their acquired knowledge.To maximize the intruder’s capabilities,channel errors are translated into the behaviors of the intruder.The participants are further categorized into honest participants and malicious participants,enabling a comprehensive evaluation of the intruder’s potential impact.By employing a typical fair exchange protocol as an illustrative example,this paper demonstrates the detailed steps of utilizing the proposed model for protocol analysis.The entire process of protocol execution under attack scenarios is presented,shedding light on the underlying reasons for the attacks and proposing corresponding countermeasures.The developedmodel enhances the ability to reason about and evaluate the security properties of fair exchange protocols,thereby contributing to the advancement of secure network transactions.展开更多
In traditional digital twin communication system testing,we can apply test cases as completely as possible in order to ensure the correctness of the system implementation,and even then,there is no guarantee that the d...In traditional digital twin communication system testing,we can apply test cases as completely as possible in order to ensure the correctness of the system implementation,and even then,there is no guarantee that the digital twin communication system implementation is completely correct.Formal verification is currently recognized as a method to ensure the correctness of software system for communication in digital twins because it uses rigorous mathematical methods to verify the correctness of systems for communication in digital twins and can effectively help system designers determine whether the system is designed and implemented correctly.In this paper,we use the interactive theorem proving tool Isabelle/HOL to construct the formal model of the X86 architecture,and to model the related assembly instructions.The verification result shows that the system states obtained after the operations of relevant assembly instructions is consistent with the expected states,indicating that the system meets the design expectations.展开更多
This work is about the progress of previous related work based on an experiment to improve the intelligence of robotic systems,with the aim of achieving more linguistic communication capabilities between humans and ro...This work is about the progress of previous related work based on an experiment to improve the intelligence of robotic systems,with the aim of achieving more linguistic communication capabilities between humans and robots.In this paper,the authors attempt an algorithmic approach to natural language generation through hole semantics and by applying the OMAS-III computational model as a grammatical formalism.In the original work,a technical language is used,while in the later works,this has been replaced by a limited Greek natural language dictionary.This particular effort was made to give the evolving system the ability to ask questions,as well as the authors developed an initial dialogue system using these techniques.The results show that the use of these techniques the authors apply can give us a more sophisticated dialogue system in the future.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
Since the formal deductive system (?) was built up in 1997, it has played important roles in the theoretical and applied research of fuzzy logic and fuzzy reasoning. But, up to now, the completeness problem of the sys...Since the formal deductive system (?) was built up in 1997, it has played important roles in the theoretical and applied research of fuzzy logic and fuzzy reasoning. But, up to now, the completeness problem of the system (?) is still an open problem. In this paper, the properties and structure of R0 algebras are further studied, and it is shown that every tautology on the R0 interval [0,1] is also a tautology on any R0 algebra. Furthermore, based on the particular structure of (?) -Lindenbaum algebra, the completeness and strong completeness of the system (?) are proved. Some applications of the system (?) in fuzzy reasoning are also discussed, and the obtained results and examples show that the system (?) is suprior to some other important fuzzy logic systems.展开更多
Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of qua...Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control.展开更多
To makesystem-of-systems combat simulation models easy to be developed and reused, simulation model formal specification and representation are researched. According to the view of system-of-systems combat simulation,...To makesystem-of-systems combat simulation models easy to be developed and reused, simulation model formal specification and representation are researched. According to the view of system-of-systems combat simulation, and based on DEVS, the simulation model's fundamental formalisms are explored. It includes entity model, system-of-systems model and experiment model. It also presents rigorous formal specification. XML data exchange standard is combined to design the XML based language, SCSL, to support simulation model representation. The corresponding relationship between SCSL and simulation model formalism is discussed and the syntax and semantics of elements in SCSL are detailed. Based on simulation model formal specification, the abstract simulation algorithm is given and SCSL virtual machine, which is capable of automatically interpreting and executing simulation model represented by SCSL, is designed. Finally an application case is presented, which can show the validation of the theory and verification of SCSL.展开更多
The research purpose is invention (construction) of a formal logical inference of the Law of Conservation of Energy within a logically formalized axiomatic epistemology-and-axiology theory Sigma from a precisely defin...The research purpose is invention (construction) of a formal logical inference of the Law of Conservation of Energy within a logically formalized axiomatic epistemology-and-axiology theory Sigma from a precisely defined assumption of a-priori-ness of knowledge. For realizing this aim, the following work has been done: 1) a two-valued algebraic system of formal axiology has been defined precisely and applied to proper-philosophy of physics, namely, to an almost unknown (not-recognized) formal-axiological aspect of the physical law of conservation of energy;2) the formal axiomatic epistemology-and-axiology theory Sigma has been defined precisely and applied to proper-physics for realizing the above-indicated purpose. Thus, a discrete mathematical model of relationship between philosophy of physics and universal epistemology united with formal axiology has been constructed. Results: 1) By accurate computing relevant compositions of evaluation-functions within the discrete mathematical model, it is demonstrated that a formal-axiological analog of the great conservation law of proper physics is a formal-axiological law of two-valued algebra of metaphysics. (A precise algorithmic definition of the unhabitual (not-well-known) notion “formal-axiological law of algebra of metaphysics” is given.) 2) The hitherto never published significantly new nontrivial scientific result of investigation presented in this article is a formal logical inference of the law of conservation of energy within the formal axiomatic theory Sigma from conjunction of the formal-axiological analog of the law of conservation of energy and the assumption of a-priori-ness of knowledge.展开更多
The N = 1 supersymmetric extensions of two integrable systems,a special negative Kadomtsev–Petviashvili(NKP)system and a(2+1)-dimensional modified Korteweg–de Vries(MKd V) system,are constructed from the Hiro...The N = 1 supersymmetric extensions of two integrable systems,a special negative Kadomtsev–Petviashvili(NKP)system and a(2+1)-dimensional modified Korteweg–de Vries(MKd V) system,are constructed from the Hirota formalism in the superspace.The integrability of both systems in the sense of possessing infinitely many generalized symmetries are confirmed by extending the formal series symmetry approach to the supersymmetric framework.It is found that both systems admit a generalization of W∞type algebra and a Kac-Moody–Virasoro type subalgebra.Interestingly,the first one of the positive flow of the supersymmetric NKP system is another N = 1 supersymmetric extension of the(2+1)-dimensional MKd V system.Based on our work,a hypothesis is put forward on a series of(2+1)-dimensional supersymmetric integrable systems.It is hoped that our work may develop a straightforward way to obtain supersymmetric integrable systems in high dimensions.展开更多
In this paper, a formal system is proposed based on beta reputation for the development of trustworthy wireless sensor networks (FRS-TWSN). Following this approach, key concepts related to reputation are formal desc...In this paper, a formal system is proposed based on beta reputation for the development of trustworthy wireless sensor networks (FRS-TWSN). Following this approach, key concepts related to reputation are formal described step by step for wireless sensor networks where sensor nodes maintain reputation for other sensors and use it to evaluate their trustworthiness. By proving some properties of beta reputation system, the beta distribution is founded to fit well to describe reputation system. Also, a case system is developed within this framework for reputation representation, updates and integration. Simulation results show this scheme not only can keep stable reputation but also can prevent the system from some attacks as bad mouthing and reputation cheating.展开更多
Cloud computing systems play a vital role in national security. This paper describes a conceptual framework called dualsystem architecture for protecting computing environments. While attempting to be logical and rigo...Cloud computing systems play a vital role in national security. This paper describes a conceptual framework called dualsystem architecture for protecting computing environments. While attempting to be logical and rigorous, formalism method is avoided and this paper chooses algebra Communication Sequential Process.展开更多
Attribute reduction of formal decision context mainly uses the relationship between two concept lattices generated by the condition and decision attributes to remove redundant condition attributes.By using decision at...Attribute reduction of formal decision context mainly uses the relationship between two concept lattices generated by the condition and decision attributes to remove redundant condition attributes.By using decision attributes to observe the covering of objects,this study defines two types of consistent sets and reducts in a consistent formal decision context based on neighbourhood systems.Four types of reductions in inconsistent formal decision contexts are also studied.The methods to calculate all types of reductions are formulated by discernibility matrix.Finally,an approach to obtain the decision rules in consistent formal decision context is proposed.展开更多
Distributed Operating System Formalization Generating System(DOSFGS)consists of agrammar subsystem DOSFSG and a semantics subsystem DOSFSS.DOSFSG is a kind ofContext-free grammar.DOSFSS is a semantics system with an o...Distributed Operating System Formalization Generating System(DOSFGS)consists of agrammar subsystem DOSFSG and a semantics subsystem DOSFSS.DOSFSG is a kind ofContext-free grammar.DOSFSS is a semantics system with an operating set.DOSFGS gen-erates a distributed operating system automatically according to the process of abstraction,description,and refinement.This paper discusses data structures,operating set and defini-tion of DOSFSS.展开更多
Control systems are vulnerable to faults in control loops where faults may cause abruptand damaging responses. These systems with fault accommodation are becoming more and moreimportant while appearing in flight contr...Control systems are vulnerable to faults in control loops where faults may cause abruptand damaging responses. These systems with fault accommodation are becoming more and moreimportant while appearing in flight control, robots control and nuclear reactor control etc, andcalling for more rigorous development approach. A formal approach is explored in this parer, basedon Extended Duration Calculus, for the development of such kind of systems. A typical exampleof control system with fault accommodation, two-level control system, is used for illstrating ourapproach. Its high level consists of an event-driven supervisor which reeds to the change of plant dueto faults occurrence, and its low level consists of normal controller, reconfigured controller and othercomponents with FDI (Fault Detection and Isolation) mechanism. Firstly performance and systemspecifications of the case are formulated in EDC; Then they are refined step wisely into specificationsof the supervisor and the low level components. Finally the whole system performance is verified inEDC framework.展开更多
With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used...With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used here can also be applied to solve other nonlinear differential-difference equation or equations.展开更多
This paper presents an augmented framework for analyzing Safety Critical Systems (SCSs) formally. Due to high risk of failure, development process of SCSs is required more attention. Model driven approaches are the on...This paper presents an augmented framework for analyzing Safety Critical Systems (SCSs) formally. Due to high risk of failure, development process of SCSs is required more attention. Model driven approaches are the one of ways to develop SCSs for accomplishing critical and complex function what SCSs are supposed to do. Two model driven approaches: Unified Modeling Language (UML) and Formal Methods are combined in proposed framework which enables the analysis, designing and testing safety properties of SCSs more rigorously in order to reduce the ambiguities and enhance the correctness and completeness of SCSs. A real time case study has been discussed in order to validate the proposed framework.展开更多
In this paper, it is emphasized that taking into consideration of imperfection of knowledge, of the team of the designers/developers, about the problem domains and environments is essential in order to develop robust ...In this paper, it is emphasized that taking into consideration of imperfection of knowledge, of the team of the designers/developers, about the problem domains and environments is essential in order to develop robust software metrics and systems. In this respect, first various possible types of imperfections in knowledge are discussed and then various available formal/mathematical models for representing and handling these imperfections are discussed. The discussion of knowledge classification & representation is from computational perspective and that also within the context of software development enterprise, and not necessarily from organizational management, from library & information science, or from psychological perspectives.展开更多
In this paper, we present a new formalism for Modeling Multi Agent Systems (MAS). Our model based a PN is able to describe not only not the internal state of each agent modeled but also its behavior. Owing to these fe...In this paper, we present a new formalism for Modeling Multi Agent Systems (MAS). Our model based a PN is able to describe not only not the internal state of each agent modeled but also its behavior. Owing to these features, one can model naturally the dynamic behavior of complex systems and the communication between these entities. For this, we propose mathematical definitions attached to firing transitions. To validate our contribution, we will deal with real examples.展开更多
Formal methods are the mathematically techniques and tools which are used at early stages of software development lifecycle processes. The utter need of using formal methods in safety critical system leads to accuracy...Formal methods are the mathematically techniques and tools which are used at early stages of software development lifecycle processes. The utter need of using formal methods in safety critical system leads to accuracy, consistency and correctness in proposed system. In safety critical real time application, requirements should be unambiguous and very accurate which can be achieved by using mathematical theorems. There is utter need to focus on the requirement phase which is the most critical phase of SDLC. This paper focuses on the use of Z notation for incorporating the accuracy, consistency, and eliminates ambiguity in safety critical system: Road Traffic Management System as a case study. The syntax, semantics, type checking and domain checking are further verified by using Z/EVES: a Z notation type checker tool.展开更多
基金funding from the National Natural Science Foundation of China (72303086)the Leading Scientist Project of Qinghai Province, China (2023-NK-147)+1 种基金the Consulting Project of Chinese Academy of Engineering (2023-XY-28,2022-XY-139)the Fundamental Research Funds for the Central Universities, China (lzujbky-2022-sp13)
文摘Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit.
基金the National Natural Science Foundation of China(Nos.61562026,61962020)Academic and Technical Leaders of Major Disciplines in Jiangxi Province(No.20172BCB22015)+1 种基金Special Fund Project for Postgraduate Innovation in Jiangxi Province(No.YC2020-B1141)Jiangxi Provincial Natural Science Foundation(No.20224ACB202006).
文摘Fair exchange protocols play a critical role in enabling two distrustful entities to conduct electronic data exchanges in a fair and secure manner.These protocols are widely used in electronic payment systems and electronic contract signing,ensuring the reliability and security of network transactions.In order to address the limitations of current research methods and enhance the analytical capabilities for fair exchange protocols,this paper proposes a formal model for analyzing such protocols.The proposed model begins with a thorough analysis of fair exchange protocols,followed by the formal definition of fairness.This definition accurately captures the inherent requirements of fair exchange protocols.Building upon event logic,the model incorporates the time factor into predicates and introduces knowledge set axioms.This enhancement empowers the improved logic to effectively describe the state and knowledge of protocol participants at different time points,facilitating reasoning about their acquired knowledge.To maximize the intruder’s capabilities,channel errors are translated into the behaviors of the intruder.The participants are further categorized into honest participants and malicious participants,enabling a comprehensive evaluation of the intruder’s potential impact.By employing a typical fair exchange protocol as an illustrative example,this paper demonstrates the detailed steps of utilizing the proposed model for protocol analysis.The entire process of protocol execution under attack scenarios is presented,shedding light on the underlying reasons for the attacks and proposing corresponding countermeasures.The developedmodel enhances the ability to reason about and evaluate the security properties of fair exchange protocols,thereby contributing to the advancement of secure network transactions.
基金supported in part by the Natural Science Foundation of Jiangsu Province in China under grant No.BK20191475the fifth phase of“333 Project”scientific research funding project of Jiangsu Province in China under grant No.BRA2020306the Qing Lan Project of Jiangsu Province in China under grant No.2019.
文摘In traditional digital twin communication system testing,we can apply test cases as completely as possible in order to ensure the correctness of the system implementation,and even then,there is no guarantee that the digital twin communication system implementation is completely correct.Formal verification is currently recognized as a method to ensure the correctness of software system for communication in digital twins because it uses rigorous mathematical methods to verify the correctness of systems for communication in digital twins and can effectively help system designers determine whether the system is designed and implemented correctly.In this paper,we use the interactive theorem proving tool Isabelle/HOL to construct the formal model of the X86 architecture,and to model the related assembly instructions.The verification result shows that the system states obtained after the operations of relevant assembly instructions is consistent with the expected states,indicating that the system meets the design expectations.
文摘This work is about the progress of previous related work based on an experiment to improve the intelligence of robotic systems,with the aim of achieving more linguistic communication capabilities between humans and robots.In this paper,the authors attempt an algorithmic approach to natural language generation through hole semantics and by applying the OMAS-III computational model as a grammatical formalism.In the original work,a technical language is used,while in the later works,this has been replaced by a limited Greek natural language dictionary.This particular effort was made to give the evolving system the ability to ask questions,as well as the authors developed an initial dialogue system using these techniques.The results show that the use of these techniques the authors apply can give us a more sophisticated dialogue system in the future.
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Since the formal deductive system (?) was built up in 1997, it has played important roles in the theoretical and applied research of fuzzy logic and fuzzy reasoning. But, up to now, the completeness problem of the system (?) is still an open problem. In this paper, the properties and structure of R0 algebras are further studied, and it is shown that every tautology on the R0 interval [0,1] is also a tautology on any R0 algebra. Furthermore, based on the particular structure of (?) -Lindenbaum algebra, the completeness and strong completeness of the system (?) are proved. Some applications of the system (?) in fuzzy reasoning are also discussed, and the obtained results and examples show that the system (?) is suprior to some other important fuzzy logic systems.
文摘Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control.
文摘To makesystem-of-systems combat simulation models easy to be developed and reused, simulation model formal specification and representation are researched. According to the view of system-of-systems combat simulation, and based on DEVS, the simulation model's fundamental formalisms are explored. It includes entity model, system-of-systems model and experiment model. It also presents rigorous formal specification. XML data exchange standard is combined to design the XML based language, SCSL, to support simulation model representation. The corresponding relationship between SCSL and simulation model formalism is discussed and the syntax and semantics of elements in SCSL are detailed. Based on simulation model formal specification, the abstract simulation algorithm is given and SCSL virtual machine, which is capable of automatically interpreting and executing simulation model represented by SCSL, is designed. Finally an application case is presented, which can show the validation of the theory and verification of SCSL.
文摘The research purpose is invention (construction) of a formal logical inference of the Law of Conservation of Energy within a logically formalized axiomatic epistemology-and-axiology theory Sigma from a precisely defined assumption of a-priori-ness of knowledge. For realizing this aim, the following work has been done: 1) a two-valued algebraic system of formal axiology has been defined precisely and applied to proper-philosophy of physics, namely, to an almost unknown (not-recognized) formal-axiological aspect of the physical law of conservation of energy;2) the formal axiomatic epistemology-and-axiology theory Sigma has been defined precisely and applied to proper-physics for realizing the above-indicated purpose. Thus, a discrete mathematical model of relationship between philosophy of physics and universal epistemology united with formal axiology has been constructed. Results: 1) By accurate computing relevant compositions of evaluation-functions within the discrete mathematical model, it is demonstrated that a formal-axiological analog of the great conservation law of proper physics is a formal-axiological law of two-valued algebra of metaphysics. (A precise algorithmic definition of the unhabitual (not-well-known) notion “formal-axiological law of algebra of metaphysics” is given.) 2) The hitherto never published significantly new nontrivial scientific result of investigation presented in this article is a formal logical inference of the law of conservation of energy within the formal axiomatic theory Sigma from conjunction of the formal-axiological analog of the law of conservation of energy and the assumption of a-priori-ness of knowledge.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11605102,11475052,11675055,and 11626140)
文摘The N = 1 supersymmetric extensions of two integrable systems,a special negative Kadomtsev–Petviashvili(NKP)system and a(2+1)-dimensional modified Korteweg–de Vries(MKd V) system,are constructed from the Hirota formalism in the superspace.The integrability of both systems in the sense of possessing infinitely many generalized symmetries are confirmed by extending the formal series symmetry approach to the supersymmetric framework.It is found that both systems admit a generalization of W∞type algebra and a Kac-Moody–Virasoro type subalgebra.Interestingly,the first one of the positive flow of the supersymmetric NKP system is another N = 1 supersymmetric extension of the(2+1)-dimensional MKd V system.Based on our work,a hypothesis is put forward on a series of(2+1)-dimensional supersymmetric integrable systems.It is hoped that our work may develop a straightforward way to obtain supersymmetric integrable systems in high dimensions.
基金the National Natural Science Foundation of China (60573043)the Natural Science Foundation of Guangdong Province (06025838)
文摘In this paper, a formal system is proposed based on beta reputation for the development of trustworthy wireless sensor networks (FRS-TWSN). Following this approach, key concepts related to reputation are formal described step by step for wireless sensor networks where sensor nodes maintain reputation for other sensors and use it to evaluate their trustworthiness. By proving some properties of beta reputation system, the beta distribution is founded to fit well to describe reputation system. Also, a case system is developed within this framework for reputation representation, updates and integration. Simulation results show this scheme not only can keep stable reputation but also can prevent the system from some attacks as bad mouthing and reputation cheating.
文摘Cloud computing systems play a vital role in national security. This paper describes a conceptual framework called dualsystem architecture for protecting computing environments. While attempting to be logical and rigorous, formalism method is avoided and this paper chooses algebra Communication Sequential Process.
基金This work was supported by the National Natural Science Foundation of China(nos.61573127 and 61502144)the Natural Science Foundation of Hebei Province(no.F2018205196)+1 种基金the Science and Technology Research Program of Higher Education Institutions of Hebei Province(nos.BJ2019014 and QN2017095)the Doctor Natural Science Foundation of Hebei Normal University(no.L2017B19).
文摘Attribute reduction of formal decision context mainly uses the relationship between two concept lattices generated by the condition and decision attributes to remove redundant condition attributes.By using decision attributes to observe the covering of objects,this study defines two types of consistent sets and reducts in a consistent formal decision context based on neighbourhood systems.Four types of reductions in inconsistent formal decision contexts are also studied.The methods to calculate all types of reductions are formulated by discernibility matrix.Finally,an approach to obtain the decision rules in consistent formal decision context is proposed.
基金Supported by the High Technology Research and Development Programme of China.
文摘Distributed Operating System Formalization Generating System(DOSFGS)consists of agrammar subsystem DOSFSG and a semantics subsystem DOSFSS.DOSFSG is a kind ofContext-free grammar.DOSFSS is a semantics system with an operating set.DOSFGS gen-erates a distributed operating system automatically according to the process of abstraction,description,and refinement.This paper discusses data structures,operating set and defini-tion of DOSFSS.
文摘Control systems are vulnerable to faults in control loops where faults may cause abruptand damaging responses. These systems with fault accommodation are becoming more and moreimportant while appearing in flight control, robots control and nuclear reactor control etc, andcalling for more rigorous development approach. A formal approach is explored in this parer, basedon Extended Duration Calculus, for the development of such kind of systems. A typical exampleof control system with fault accommodation, two-level control system, is used for illstrating ourapproach. Its high level consists of an event-driven supervisor which reeds to the change of plant dueto faults occurrence, and its low level consists of normal controller, reconfigured controller and othercomponents with FDI (Fault Detection and Isolation) mechanism. Firstly performance and systemspecifications of the case are formulated in EDC; Then they are refined step wisely into specificationsof the supervisor and the low level components. Finally the whole system performance is verified inEDC framework.
基金The project supported by National Natural Science Foundation of China and the Natural Science Foundation of Shandong Province.
文摘With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used here can also be applied to solve other nonlinear differential-difference equation or equations.
文摘This paper presents an augmented framework for analyzing Safety Critical Systems (SCSs) formally. Due to high risk of failure, development process of SCSs is required more attention. Model driven approaches are the one of ways to develop SCSs for accomplishing critical and complex function what SCSs are supposed to do. Two model driven approaches: Unified Modeling Language (UML) and Formal Methods are combined in proposed framework which enables the analysis, designing and testing safety properties of SCSs more rigorously in order to reduce the ambiguities and enhance the correctness and completeness of SCSs. A real time case study has been discussed in order to validate the proposed framework.
文摘In this paper, it is emphasized that taking into consideration of imperfection of knowledge, of the team of the designers/developers, about the problem domains and environments is essential in order to develop robust software metrics and systems. In this respect, first various possible types of imperfections in knowledge are discussed and then various available formal/mathematical models for representing and handling these imperfections are discussed. The discussion of knowledge classification & representation is from computational perspective and that also within the context of software development enterprise, and not necessarily from organizational management, from library & information science, or from psychological perspectives.
文摘In this paper, we present a new formalism for Modeling Multi Agent Systems (MAS). Our model based a PN is able to describe not only not the internal state of each agent modeled but also its behavior. Owing to these features, one can model naturally the dynamic behavior of complex systems and the communication between these entities. For this, we propose mathematical definitions attached to firing transitions. To validate our contribution, we will deal with real examples.
文摘Formal methods are the mathematically techniques and tools which are used at early stages of software development lifecycle processes. The utter need of using formal methods in safety critical system leads to accuracy, consistency and correctness in proposed system. In safety critical real time application, requirements should be unambiguous and very accurate which can be achieved by using mathematical theorems. There is utter need to focus on the requirement phase which is the most critical phase of SDLC. This paper focuses on the use of Z notation for incorporating the accuracy, consistency, and eliminates ambiguity in safety critical system: Road Traffic Management System as a case study. The syntax, semantics, type checking and domain checking are further verified by using Z/EVES: a Z notation type checker tool.