基于时序逻辑的面向实现的协议规范语言

在多种形式化描述语言和时序逻辑原理的研究之上；针对通讯协议的特点提出一个协议模型思想，并设计了实现此模型协议描述语言．本方法的特点是：基于时序逻辑；引入了面向对象的概念，对事件有强的描述能力，让描述更接近于现实；扩展了对事件的描述．能描述事件的随机发生，我们已将之成功地应用于对超文本协议的描述．     

Automata for Epistemic Temporal Logic with Synchronous Communication

We suggest that developing automata theoretic foundations is relevant for knowledge theory, so that we study not only what is known by agents, but also the mechanisms by which such knowledge is arrived at. We define a class of epistemic automata, in which agents’ local states are annotated with abstract knowledge assertions about others. These are finite state agents who communicate synchronously with each other and information exchange is ‘perfect’. We show that the class of recognizable languages has good closure properties, leading to a Kleene-type theorem using what we call regular knowledge expressions. These automata model distributed causal knowledge in the following way: each agent in the system has a partial knowledge of the temporal evolution of the system, and every time agents synchronize, they update each other’s knowledge, resulting in a more up-to-date view of the system state. Hence we show that these automata can be used to solve the satisfiability problem for a natural epistemic temporal logic for local properties. Finally, we characterize the class of languages recognized by epistemic automata as the regular consistent languages studied in concurrency theory.     

基于时态逻辑的协议RSL形式化描述

研究以RAISE规范语言(RSL)描述时态逻辑中always算子、sometimes算子和until算子的方法以及对复合时态算子的描述方法,提出在时态逻辑模型基础上用RSL对协议进行形式化描述的步骤,以AB协议为示例,给出其基于时态逻辑模型的RSL描述,从而证明该描述模型有利于协议验证和协议测试用例生成的自动实现。     

实时时序逻辑语言XYZ/RE到时间自动机的映射

时间自动机是一种重要的实时系统建模工具。本文建立了实时时序逻辑语言XYZ/RE到时间自动机的一种映射机制,将XYZ/RE所描述的系统进程直接转换为时间自动机,这样不但可以准确捕获实时系统功能和控制行为,还可以利用基于时间自动机的验证工具UPPAAL对XYZ/RE描述的系统正确性进行检测。最后本文通过一个实例的描述与检测,验证了映射机制的有效性。     

实时系统形式规格说明在PVS中的建立

本文首先简介了时间自动机和时间B櫣chi自动机形式模型,结合时间化时序逻辑(TimedTemporalLogic)的语法和语义,利用定理证明器PVS(PrototypeVerificationSystem)实现了定义在时间自动机状态(或运行)上的时间化分支(或线性)时序逻辑规格说明的形式体系。在此基础上,结合一个经典的实时系统实例,用该体系对其实时特性进行了形式描述和形式验证,并得到了良好的结果。     

有穷时间投影时序逻辑的完备公理系统

为采用定理证明的方法对并发及交互式系统进行验证,研究了有穷论域下有穷时间一阶投影时序逻辑(projection temporal logic,简称PTL)的一个完备公理系统.在介绍PTL的语法、语义并给出公理系统后,提出了PTL公式的正则形(normal form,简称NF)和正则图(normal form graph,简称NFG).基于NF给出了NFG的构造算法,并利用NFG可描述公式模型的性质证明PTL公式的可满足性判定定理和公理系统的完备性.最后,结合实例展示了PTL及其公理系统在系统验证中的应用.结果表明,基于PTL的定理证明方法可方便用于并发系统的建模与验证.     

一种用于静态分析的规约语言设计与实现

介绍一种用于程序静态分析检测的规约语言的设计与实现，对该语言的理论基础、要素、语法等进行了详细阐述，并通过对实验结果的对比分析，证明该语言的可靠性和实用性。     

多媒体节目时序描述的组合技术

组合性是形式描述研究的基本问题,便于大型程序的设计、分析、测试和复用.为了方便用户编制大型多媒体系统的时序描述,组合模型是必须的.目前,这样的模型有基于语言的、基于图形的、基于时间区间的和面向对象的等等.但是,这些模型描述层次过低,很难支持两个多媒体节目之间的时序描述.通过引入单位流的概念和扩展两种时序关系,研究一种多媒体节目时序描述的结构化技术,使复杂的多媒体节目易于理解,以方便用户运用组合方法把一些可以复用于不同多媒体节目的节目模块进行组合设计.     

数据融合系统的时序有限自动机模型及性能分析方法

数据融合系统的各种算法是当前研究的热点问题,但缺乏有效数学工具对数据融合系统进行描述和分析.本文提出了时序有限自动机,用它建立数据融合系统的形式化模型,并且给出了时序有限自动机模型的可达性分析方法,用于分析数据融合系统的性能和行为.同时,给出了建立时序有限自动机模型和数据融合系统的正确性和实时性分析算法.     

基于时序逻辑语言描述的监控系统的软件体系结构求精

该文提出了一种基于组件的软件体系结构求精方法,主要通过一个具体实例———移动通信监控系统,基于时序逻辑语言XYZ/E形式化描述其体系结构,对该求精方法及过程做进一步阐述。     

卷染机模糊控制系统设计

采用模糊逻辑控制器设计控制规律,提出了对具有明显耦合作用的二输入/二输出系统的一种模糊控制器设计方案,即"在线规则自调整"和"主从交替"策略.在模糊控制系统中采用了变频调速器作为执行元件控制张力和线速.以卷染机为控制对象,用8098和两台变频调速器实现了整个模糊控制系统,样机运行的测试结果表明,该模糊控制系统设计是成功的.     

Reasoning in a Restricted Temporal Logic

We consider RTL, a linear time propositional temporal logic whose only modalities are the [formula] (eventually) operator and its dual [formula] (always). Although less expressive than the full temporal logic, RTL is the fragment of temporal logic that is used most often and in many verification systems. Indeed, many properties of distributed systems discussed in the literature are RTL properties. Another advantage of RTL over the full temporal logic is in the decidability procedure; while deciding satisfiability of a formula in full temporal logic is a PSPACE complete procedure, doing so for an RTL formula is in NP. We characterize the class of ω-regular languages that are definable in RTL and show simple translations between ω-regular sets and RTL formulae that define them. We explore the applications of RTL in reasoning about communication systems. Finally, we relate variants of RTL (when interpreted over a real line segments) to several fragments of Interval Modal Logic and show that the satisfiability problem for RTL when interpreted over a real line is NP-complete.     

Receding Horizon Control for a Class of Discrete-Event Systems With Real-Time Constraints

We consider discrete-event systems (DES) involving the control of tasks with real-time constraints. When future event time information is limited, we propose a receding horizon (RH) controller in which only some future information is available within a time window. Analyzing sample paths obtained under this scheme and comparing them to optimal sample paths (obtained when all event times are known), we derive a number of attractive properties of the RH controller, including: the fact that it still guarantees all real-time constraints; there are segments of its sample path over which all controls are still optimal; the error relative to the optimal task departure times is decreasing under certain conditions. Simulation results are included to verify the properties of the controller and show that its performance can be near-optimal even if the RH window size is relatively small     

Communication Complexity Method for Measuring Nondeterminism in Finite Automata

While deterministic finite automata seem to be well understood, surprisingly many important problems concerning nondeterministic finite automata (nfa's) remain open. One such problem area is the study of different measures of nondeterminism in finite automata and the estimation of the sizes of minimal nondeterministic finite automata. In this paper the concept of communication complexity is applied in order to achieve progress in this problem area. The main results are as follows:1. Deterministic communication complexity provides lower bounds on the size of nfa's with bounded unambiguity. Applying this fact, the proofs of several results about nfa's with limited ambiguity can be simplified and presented in a uniform way.2. There is a family of languages KON_k² with an exponential size gap between nfa's with polynomial leaf number/ambiguity and nfa's with ambiguity k. This partially provides an answer to the open problem posed by B. Ravikumar and O. Ibarra (1989, SIAM J. Comput.18, 1263–1282) and H. Leung (1998, SIAM J. Comput.27, 1073–1082).     

An Overview of Anna, a Specification Language for Ada

The Anna approach to specification language design strengthens the existing explanatory constructs in Ada and adds new ones where there is an obvious need.     

有限自动机理论在高速公路收费中的应用

阐述了有限自动机理论及其在高速公路车道收费控制中的应用 ,最后描述了系统硬件结构框图和软件设计。     

Process Algebras as Specification Language: (work in progress)

Recent approaches to the combination of process algebras and temporal logic have shown that it is possible to specify logical formulae as processes. The presented work exploits the applicability of these approaches, in the context of globally clocked process algebras, and shows how logical expressions describing the history of a system can be used to simplify system specifications with process algebras. In order to allow modelling of composed systems at a high level, one-way communication is used to build the model of the system. Finally, an outline of how these models can be refined is given.     

Syntax and Semantics for a Fuzzy Temporal Constraint Logic

In this paper we establish the relationship between the syntax and semantics of a fuzzy temporal constraint logic (FTCL) proposed by Cárdenas et al. FTCL enables us to express interrelated events by means of fuzzy temporal constraints. Moreover, it provides a resolution principle for performing inferences which take these constraints into account. FTCL is compatible with the theoretical temporal reasoning model proposed by Marín et al. – the Fuzzy Temporal Constraint Networks (FTCN). The main contributions of this paper are, on the one hand, the proofs of the FTCL-deduction and the FTCL-refutation theorems, and, on the other, the proof of the soundness of the refutation by resolution in this formal system, together with an exhaustive study of its completeness.