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Formal Modeling of Self-Adaptive Resource Scheduling in Cloud
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作者 Atif Ishaq Khan Syed Asad Raza Kazmi Awais Qasim 《Computers, Materials & Continua》 SCIE EI 2023年第1期1183-1197,共15页
A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive... A self-adaptive resource provisioning on demand is a critical factor in cloud computing.The selection of accurate amount of resources at run time is not easy due to dynamic nature of requests.Therefore,a self-adaptive strategy of resources is required to deal with dynamic nature of requests based on run time change in workload.In this paper we proposed a Cloud-based Adaptive Resource Scheduling Strategy(CARSS)Framework that formally addresses these issues and is more expressive than traditional approaches.The decision making in CARSS is based on more than one factors.TheMAPE-K based framework determines the state of the resources based on their current utilization.Timed-Arc Petri Net(TAPN)is used to model system formally and behaviour is expressed in TCTL,while TAPAAL model checker verifies the underline properties of the system. 展开更多
关键词 formal modeling MULTI-AGENT SELF-ADAPTIVE cloud computing
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A STUDY ON FORMAL MODEL INTEGRATION
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作者 Wang Jiayang Chen Songqiao Luo An 《Journal of Electronics(China)》 2006年第5期758-762,共5页
Model integration is an important section of the model management research area. The paper puts forward a formalization representation of model, and presents some concepts, such as the compound model re- lation, the c... Model integration is an important section of the model management research area. The paper puts forward a formalization representation of model, and presents some concepts, such as the compound model re- lation, the composite model and so on. Additionally, the existence of model integration is also analyzed in de- tail and several sufficient conditions are proved. 展开更多
关键词 formal model Multi-repositories model integration
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Envisioning the blueprint:Aeronautics in large models era
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作者 Weiwei ZHANG Shule ZHAO 《Chinese Journal of Aeronautics》 2025年第8期139-141,共3页
Following the groundbreaking introduction of the Transformer architecture in 2017,the development of Large Language Models(LLMs)formally commenced.In May 2020,Chat GPT-3,with over one hundred billion parameters,entere... Following the groundbreaking introduction of the Transformer architecture in 2017,the development of Large Language Models(LLMs)formally commenced.In May 2020,Chat GPT-3,with over one hundred billion parameters,entered the public eye,marking a significant milestone in LLM advancement. 展开更多
关键词 AERONAUTICS large languagemodels transformer architecture transformerarchitecture llms chatgpt large language models llms formally
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A formal model for access control with supporting spatial context 被引量:7
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作者 ZHANG Hong HE YePing SHI ZhiGuo 《Science in China(Series F)》 2007年第3期419-439,共21页
There is an emerging recognition of the importance of utilizing contextual information in authorization decisions. Controlling access to resources in the field of wireless and mobile networking require the definition ... There is an emerging recognition of the importance of utilizing contextual information in authorization decisions. Controlling access to resources in the field of wireless and mobile networking require the definition of a formal model for access control with supporting spatial context. However, traditional RBAC model does not specify these spatial requirements. In this paper, we extend the existing RBAC model and propose the SC-RBAC model that utilizes spatial and location-based information in security policy definitions. The concept of spatial role is presented, and the role is assigned a logical location domain to specify the spatial boundary. Roles are activated based on the current physical position of the user which obtsined from a specific mobile terminal. We then extend SC-RBAC to deal with hierarchies, modeling permission, user and activation inheritance, and prove that the hierarchical spatial roles are capable of constructing a lattice which is a means for articulate multi-level security policy and more suitable to control the information flow security for safety-critical location-aware information systems. Next, con- strained SC-RBAC allows express various spatial separations of duty constraints, location-based cardinality and temporal constraints for specify fine-grained spatial semantics that are typical in location-aware systems. Finally, we introduce 9 in- variants for the constrained SC-RBAC and its basic security theorem is proven. The constrained SC-RBAC provides the foundation for applications in need of the constrained spatial context aware access control. 展开更多
关键词 information security RBAC spatial context LATTICE MLS CONSTRAINTS formal model
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A formal model for integrity protection based on DTE technique 被引量:4
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作者 JI Qingguang QING Sihan HE Yeping 《Science in China(Series F)》 2006年第5期545-565,共21页
In order to provide integrity protection for the secure operating system to satisfy the structured protection class' requirements, a DTE technique based integrity protection formalization model is proposed after the ... In order to provide integrity protection for the secure operating system to satisfy the structured protection class' requirements, a DTE technique based integrity protection formalization model is proposed after the implications and structures of the integrity policy have been analyzed in detail. This model consists of some basic rules for configuring DTE and a state transition model, which are used to instruct how the domains and types are set, and how security invariants obtained from initial configuration are maintained in the process of system transition respectively. In this model, ten invariants are introduced, especially, some new invariants dealing with information flow are proposed, and their relations with corresponding invariants described in literatures are also discussed. The thirteen transition rules with well-formed atomicity are presented in a well-operational manner. The basic security theorems correspond to these invariants and transition rules are proved. The rationalities for proposing the invariants are further annotated via analyzing the differences between this model and ones described in literatures. At last but not least, future works are prospected, especially, it is pointed out that it is possible to use this model to analyze SE-Linux security. 展开更多
关键词 formal model integrity policy information flow DOMAIN type.
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Formal modeling and quantitative evaluation for information system survivability based on PEPA 被引量:2
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作者 WANG Jian WANG Hui-qiang ZHAO Guo-sheng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2008年第2期88-96,113,共10页
Survivability should be considered beyond security for information system. To assess system survivability accurately, for improvement, a formal modeling and analysis method based on stochastic process algebra is propo... Survivability should be considered beyond security for information system. To assess system survivability accurately, for improvement, a formal modeling and analysis method based on stochastic process algebra is proposed in this article. By abstracting the interactive behaviors between intruders and information system, a transferring graph of system state oriented survivability is constructed. On that basis, parameters are defined and system behaviors are characterized precisely with performance evaluation process algebra (PEPA), simultaneously considering the influence of different attack modes. Ultimately the formal model for survivability is established and quantitative analysis results are obtained by PEPA Workbench tool. Simulation experiments show the effectiveness and feasibility of the developed method, and it can help to direct the designation of survivable system. 展开更多
关键词 SURVIVABILITY stochastic process algebra performanceevaluation process algebra formal modeling quantitativeevaluation
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A new formal model for privilege control with supporting POSIX capability mechanism 被引量:3
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作者 JIQingguang QINGSihan HEYeping 《Science in China(Series F)》 2005年第1期46-66,共21页
In order to enforce the least privilege principle in the operating system, it is necessary for the process privilege to be effectively controlled; but this is very difficult because a process always changes as time ch... In order to enforce the least privilege principle in the operating system, it is necessary for the process privilege to be effectively controlled; but this is very difficult because a process always changes as time changes. In this paper, based on the analysis on how the process privilege is generated and how it works, a hierarchy implementing the least privilege principle with three layers, i.e. administration layer, functionality control layer and performance layer, is posed. It is clearly demonstrated that to bound privilege's working scope is a critical part for controlling privilege, but this is only mentioned implicitly while not supported in POSIX capability mechanism. Based on analysis of existing control mechanism for privilege, not only an improved capability inheritance formula but also a new complete formal model for controlling process based on integrating RBAC, DTE, and POSIX capability mechanism is introduced. The new invariants in the model show that this novel privilege control mechanism is different from RBAC's, DTE's, and POSIX's, and it generalizes subdomain control mechanism and makes this mechanism dynamic. 展开更多
关键词 formal model least privilege role DOMAIN capability.
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Binary Logic State Transition Oriented Formal General Reliability Model 被引量:2
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作者 周一舟 任羿 +2 位作者 刘林林 马政 王自力 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第4期482-488,共7页
There were various conventional modeling techniques with varied semantics for system reliability assessment, such as fault trees(FT), Markov process(MP), and Petri nets. However, it is strenuous to construct and to ma... There were various conventional modeling techniques with varied semantics for system reliability assessment, such as fault trees(FT), Markov process(MP), and Petri nets. However, it is strenuous to construct and to maintain models utilizing these formalisms throughout the life cycle of system under development. This paper proposes a unified formal modeling language to build a general reliability model. The method eliminates the gap between the actual system and reliability model and shows details of the system clearly. Furthermore,the model could be transformed into FT and MP through specific rules defined by a formal language to assess system-level reliability. 展开更多
关键词 reliability formal modeling method fault trees(FT) Markov process(MP) general reliability model(GRM)
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A formal model for plastic human computer interfaces
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作者 Abdelkrim CHEBIEB Yamine AIT AMEUR 《Frontiers of Computer Science》 SCIE EI CSCD 2018年第2期351-375,共25页
The considerable and significant progress achieved in the design and development of new interaction devices between man and machine has enabled the emergence of various powerful and efficient input and/or output devic... The considerable and significant progress achieved in the design and development of new interaction devices between man and machine has enabled the emergence of various powerful and efficient input and/or output devices. Each of these new devices brings specific interaction modes. With the emergence of these devices, new interaction techniques and modes arise and new interaction capabilities are offered. New user interfaces need to be designed or former ones need to evolve. The design of so called plastic user interfaces contributes to handling such evolutions. The key requirement for the design of such a user interface is that the new obtained user interface shall be adapted to the application and have, at least, the same behavior as the previous (adapted) one. This paper proposes to address the problem of user interface evolution due to the introduction of new interaction devices and/or new interaction modes. More, precisely, we are interested by the study of the design process of a user interface resulting from the evolution of a former user interface due to the introduction of new devices and/or new interaction capabilities. We consider that interface behaviors are described by labelled transition systems and comparison between user interfaces is handled by an extended definition of the bi-simulation relationship to compare user interface behaviors when interaction modes are replaced by new ones. 展开更多
关键词 formal modeling and verification ontology based modeling plastic user interfaces adaptive systems
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Research on system-of-systems combat simulation model formal specification and representation 被引量:3
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作者 Liu Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期901-909,共9页
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
关键词 simulation model formalism simulation model representation system-of-systems combat simulation language simulation virtual machine.
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Establishing formal state space models via quantization forquantum control systems 被引量:2
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作者 DongDaoyi ChenZonghai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期398-402,共5页
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
关键词 quantum control systems formal state space models quantization.
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Formal Verification of TASM Models by Translating into UPPAAL 被引量:1
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作者 胡凯 张腾 +3 位作者 杨志斌 顾斌 蒋树 姜泮昌 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期51-54,共4页
Timed abstract state machine(TASM) is a formal specification language used to specify and simulate the behavior of real-time systems. Formal verification of TASM model can be fulfilled through model checking activitie... Timed abstract state machine(TASM) is a formal specification language used to specify and simulate the behavior of real-time systems. Formal verification of TASM model can be fulfilled through model checking activities by translating into UPPAAL. Firstly, the translational semantics from TASM to UPPAAL is presented through atlas transformation language(ATL). Secondly, the implementation of the proposed model transformation tool TASM2UPPAAL is provided. Finally, a case study is given to illustrate the automatic transformation from TASM model to UPPAAL model. 展开更多
关键词 timed abstract state machine(TASM) formal verification model transformation atlas transformation language(ATL) UPPAAL
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A Novel Formal Theory for Security Protocol Analysis of Denial of Service Based on Extended Strand Space Model
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作者 JIANG Rui 《China Communications》 SCIE CSCD 2010年第4期23-28,共6页
Denial of Service Distributed Denial of Service (DOS) attack, especially (DDoS) attack, is one of the greatest threats to Internet. Much research has been done for it by now, however, it is always concentrated in ... Denial of Service Distributed Denial of Service (DOS) attack, especially (DDoS) attack, is one of the greatest threats to Internet. Much research has been done for it by now, however, it is always concentrated in the behaviors of the network and can not deal with the problem exactly. In this paper, we start from the security of the protocol, then we propose a novel theory for security protocol analysis of Denial of Service in order to deal with the DoS attack. We first introduce the conception of weighted graph to extend the strand space model, then we extend the penetrator model and define the goal of anti-DoS attack through the conception of the DoS-stop protocol, finally we propose two kinds of DoS test model and erect the novel formal theory for security protocol analysis of Denial of Service. Our new formal theory is applied in two example protocols. It is proved that the Internet key exchange (IKE) easily suffers from the DoS attacks, and the efficient DoS- resistant secure key exchange protocol (JFK) is resistant against DoS attack for the server, respectively. 展开更多
关键词 Denial of Service Security Protocol Analysis formal Theory Strand Space model Internet Key Exchange
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PLC Modeling and Checking Based on Formal Method
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作者 Yueshan Zheng Guiming Luo +2 位作者 Junbo Sun Junjie Zhang Zhenfeng Wang 《Journal of Software Engineering and Applications》 2010年第11期1054-1059,共6页
High reliability is the key to performance of electrical control equipment. PLC combines computer technology, automatic control technology and communication technology and becomes widely used for automation of industr... High reliability is the key to performance of electrical control equipment. PLC combines computer technology, automatic control technology and communication technology and becomes widely used for automation of industrial processes. Some requirements of complex PLC systems cannot be satisfied by the traditional verification methods. In this paper, an efficient method for the PLC systems modeling and verification is proposed. To ensure the high-speed property of PLC, we proposed a technique of “Time interval model” and “notice-waiting”. It could reduce the state space and make it possible to verify some complex PLC systems. Also, the conversion from the built PLC model to the Promela language is obtained and a tool PLC-Checker for modeling and checking PLC systems are designed. Using PLC-Checker to check a classical PLC example, a counter-example is found. Although the probability of this logic error occurs very small, it could result in system crash fatally. 展开更多
关键词 model CHECKING PLC modeling PLC-Checker formal Method
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Comparison of the Molecular Interaction Volume Model with the Unified Interaction Parameter Formalism in the Fe-Cr-Ni Liquid Alloys at 1873 K
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作者 Dongping TAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第4期559-564,共6页
The molecular interaction volume model (MIVM) for a general ternary system was deduced in detail for further clarifying and understanding its general multicomponent expression. Both MIVM and the unified interaction ... The molecular interaction volume model (MIVM) for a general ternary system was deduced in detail for further clarifying and understanding its general multicomponent expression. Both MIVM and the unified interaction parameter formalism (UIPF) can be used to predict the activities of solutes and solvents in the Fe-Cr-Ni liquid alloys. But the former employs only the infinite dilute activity coefficients, and the later is not applicable without the dilute binary and ternary interaction parameters. MIVM has a certain physical meaning from the viewpoint of statistical thermodynamics, so it is an alternative for the estimation of activity coefficients of the solutes and solvents in a dilute or finite concentration metal solution where the interaction parameters are absent or their accuracies are questionable. 展开更多
关键词 ACTIVITY PREDICTION Molecular interaction volume model Unified interaction parameter formalism
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复杂系统的形式化建模及量化分析方法综述
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作者 王慧强 林烊 吕宏武 《计算机科学》 北大核心 2025年第9期346-359,共14页
形式化模型是系统验证和性能分析的重要基础手段,在系统设计阶段即可评估复杂系统可行性和性能边界,被广泛用于各类复杂系统的抽象仿真与理论分析。由于系统交互模式逐渐向多元化、动态化转变,这加剧了系统的复杂性和不确定性。对此,以... 形式化模型是系统验证和性能分析的重要基础手段,在系统设计阶段即可评估复杂系统可行性和性能边界,被广泛用于各类复杂系统的抽象仿真与理论分析。由于系统交互模式逐渐向多元化、动态化转变,这加剧了系统的复杂性和不确定性。对此,以形式化建模的核心评价要素为出发点,系统分析了几种典型的形式化建模方法的优势和不足,为复杂系统形式化建模提供了技术参考。首先,提出形式化建模及模型求解方法的评价要素框架。其次,对常见形式化建模方法进行分类,阐述了不同形式化方法的实现原理、优势、局限及适用的应用场景。再次,围绕模型求解过程中状态空间爆炸问题,对比了目前典型的求解方法,并结合评价框架,探讨了不同方法在不同应用场景下的适用性;在此基础上,剖析了基于进程代数的2种典型应用案例。最后,总结了形式化建模和量化分析领域的研究热点,并展望了未来的发展方向。 展开更多
关键词 性能评估 形式化建模 复杂系统 模型求解 状态空间爆炸
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基于流计算的动车组PHM模型处理框架
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作者 李燕 王辉 +2 位作者 杨春辉 李超旭 赵士伟 《计算机应用与软件》 北大核心 2025年第7期27-32,共6页
针对动车组故障预测与健康管理(Prognostics and Health Management,PHM)实时海量数据解析处理与模型计算问题,提出一种基于流计算的动车组PHM模型处理框架。首先分析动车组车载数据处理流程,然后基于Spark Streaming给出动车组PHM模型... 针对动车组故障预测与健康管理(Prognostics and Health Management,PHM)实时海量数据解析处理与模型计算问题,提出一种基于流计算的动车组PHM模型处理框架。首先分析动车组车载数据处理流程,然后基于Spark Streaming给出动车组PHM模型处理的总体框架。针对实时海量数据解析处理,首先分析解析前的车载数据结构,定义解析后的车载数据结构,然后设计通用化数据解析组件,给出流计算实现方式。针对模型计算,详细给出PHM模型的形式化定义,包括模型的基本信息、输入、输出和逻辑主体等,根据此定义设计模型通用组件,实现模型的快速研发、高效计算和统一应用。通过动车组PHM系统的有效应用,证明了该框架可以很好地满足海量数据的实时计算需求。 展开更多
关键词 动车组 故障预测与健康管理 流计算 模型 形式化 组件化
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基于形式理性与实质理性的大模型价值对齐机制
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作者 程聪 陈佳晨 严璐璐 《技术经济》 北大核心 2025年第1期28-39,共12页
大模型价值对齐是关涉企业乃至社会在采用大模型技术进行安全协作的全球性议题。如何实现大模型行为与决策者的价值意图及社会规范系统保持一致,成为确保大模型应用安全性和信任度的核心问题。首先,本文引入马克斯•韦伯提出的形式理性... 大模型价值对齐是关涉企业乃至社会在采用大模型技术进行安全协作的全球性议题。如何实现大模型行为与决策者的价值意图及社会规范系统保持一致,成为确保大模型应用安全性和信任度的核心问题。首先,本文引入马克斯•韦伯提出的形式理性和实质理性两个重要哲学概念,探讨大模型价值对齐机制。研究发现,大模型应用于企业管理存在四种价值对齐状态:“高形式理性-低实质理性”的技术偏移、“高实质理性-低形式理性”的价值优先、“低形式理性-低实质理性”的对齐失效及“高形式理性-高实质理性”的动态对齐。其次,甄别了透明性、清晰性和社会性三种价值对齐的分析标准。最后,构建了大模型应用于企业管理的价值对齐实现路径,包括“技术偏移→动态对齐”的认知能力具身性路径、“价值优先→动态对齐”技术意向性的清晰化路径,以及“对齐失效→动态对齐”意义建构路径。研究成果为大模型应用于企业管理的价值对齐机制提供理论支撑与实践启示。 展开更多
关键词 大模型技术 价值对齐 形式理性 实质理性
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面向航空软件需求模型的MC/DC测试用例生成方法 被引量:1
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作者 丁鼎 胡军 +2 位作者 王康星 董泽华 王立松 《小型微型计算机系统》 北大核心 2025年第7期1783-1792,共10页
充分的测试是确保现代航空软件正常运行的必要环节,而传统软件测试方法往往难以满足要求.为此,本文设计了一种面向航空软件领域的测试用例自动生成方法,为自然语言描述下的航空软件需求构建变量关系模型,解析其模型语义创建需求语义树,... 充分的测试是确保现代航空软件正常运行的必要环节,而传统软件测试方法往往难以满足要求.为此,本文设计了一种面向航空软件领域的测试用例自动生成方法,为自然语言描述下的航空软件需求构建变量关系模型,解析其模型语义创建需求语义树,根据安全关键等级选取测试路径、生成不同的覆盖集.为缓解条件互相关联而可能导致修改的条件/判定覆盖失效的问题,本文定义了适用于该需求模型的耦合条件判断及约束准则,提出3种修改的条件/判定覆盖形式并给出相应的覆盖集生成方法;基于覆盖集所确定的等价类和边界,设计了合理有效的测试用例选取策略,自动生成测试用例集.最后,对一个航空软件需求实例进行形式化建模和测试用例生成,证明了上述方法的可行性. 展开更多
关键词 测试用例生成 修改的条件/判定覆盖 基于需求的测试 形式化需求建模
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机载软件层次化需求的形式化建模与分析 被引量:2
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作者 王康星 胡军 +3 位作者 王立松 丁鼎 董亚炯 戴嘉磊 《南京航空航天大学学报(自然科学版)》 北大核心 2025年第1期195-204,共10页
越来越复杂的多层级功能需求给高安全机载软件的设计开发带来了重要挑战。本文给出了一个面向工程应用领域具有层次化语义特征的软件需求形式化建模与分析方法。首先,设计了一个层次化的形式化需求模型。层次化变量关系模型(Hierarchica... 越来越复杂的多层级功能需求给高安全机载软件的设计开发带来了重要挑战。本文给出了一个面向工程应用领域具有层次化语义特征的软件需求形式化建模与分析方法。首先,设计了一个层次化的形式化需求模型。层次化变量关系模型(Hierarchical variable relation model,HVRM)引入工程领域中典型的功能模块属性以及端口等概念来表达系统功能的层次化特征语义,同时也具备原有变量关系模型(Variable relation model,VRM)中基于表格形式的形式化语义,可表示包括条件型、事件型、多维度模式转换等多种类需求的语义信息。进而,基于需求的一致性完整性要求确立了VRM一致性完整性约束簇。其次,设计了一个将工程条目化需求建模为HVRM形式化需求模型的处理框架,并在一个机载软件需求工具平台(Hierarchical avionics requirement tools,HART)中进行了处理功能和需求追溯功能的实现和集成。最后采用某机型自动飞行系统中飞行模式转换软件逻辑需求进行了实例需求建模和模型分析。 展开更多
关键词 计算机软件与理论 需求工程 形式化方法 需求建模与分析 飞行控制系统
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