可视化语言技术在软件开发中的应用

可视化语言技术比一维文本语言在描述软件组成方面具有优越性.由于图表和图形概念在系统建模中的广泛使用,可视化语言可以应用于需求分析、设计、测试和维护等软件开发的各个阶段.除了具有直观易见的特点之外,图文法在计算机上的精确建模和验证能力,为设计可视化语言提供了一个坚实的理论基础.讨论了可视化语言的形式理论基础,回顾了相关的可视化图形编程环境.特别提出了一种空间图文法,并且用该图文法定义了统一建模语言的行为语义.基于空间图文法,开发了一种基于模式驱动的框架,以帮助软件架构与设计.     

The formal-CAFE methodology and model checking patterns in the specification of e-commerce systems

Electronic commerce is an important application that has evolved significantly recently. However, electronic commerce systems are complex and difficult to be correctly designed. Guaranteeing the correctness of an e-commerce system is not an easy task due to the great amount of scenarios where errors occur, many of them very subtle. In this work we presents a methodology that uses formal-method techniques, specifically symbolic model checking, to design electronic commerce applications and to automatically verify them. Also, a model checking pattern hierarchy has been developed—it specifies patterns to construct and verify the formal model of e-commerce systems. We consider this research the first step to the development of a framework, which will integrate the methodology, an e-commerce specification language based on business rules, and a model checker. Adriano Pereira received the B.S. and M.S. degrees in computer science in 2000 and 2002, respectively, and he is currently pursuing the Ph.D. degree in computer science from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His current interests are on performance analysis and modeling of e-business and distributed systems, and formal methods. Mark Song received the B.S., M.S. and Ph.D. degrees in computer science from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His current interests are on distributed systems and formal methods – especially BMC (Bounded Model Checking). Gustavo Franco received the B.S. and M.S. degrees in computer science in 2001 and 2004, respectively, from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His research was on modeling the user behavior of e-business and distributed systems, and formal methods. Actually his current interests are on software engeneering and project management of IT projects.     

基于场景分析的系统形式化模型生成方法

采用形式化方法对系统的安全性进行分析与验证,是构造可靠安全软件系统的一个重要途径。当前的形式化安全分析方法,面临着系统的形式化建模难的问题。以铁路车站联锁系统中基本进路建立为例,提出基于场景分析的系统形式化模型生成方法。该方法首先采用OCL前/后置条件分析法对UML时序场景作一致性分析,然后将UML时序图中对象交互的行为序列转换成FSP进程代数模型,进而得到系统的形式化模型。该方法为系统的形式化建模提供了新思路,从安全质量方面改善了安全苛求软件的设计与开发,丰厚了基于模型的软件形式化开发方法。     

Specifying behavioral semantics of UML diagrams through graph transformations

The Unified Modeling Language (UML) has been widely accepted as a standard for modeling software systems from various perspectives. The intuitive notations of UML diagrams greatly improve the communication among developers. However, the lack of a formal semantics makes it difficult to automate analysis and verification. This paper offers a graphical yet formal approach to specifying the behavioral semantics of statechart diagrams using graph transformation techniques. It supports many advanced features of statecharts, such as composite states, firing priority, history, junction, and choice. In our approach, a graph grammar is derived automatically from a state machine to summarize the hierarchy of states. Based on the graph grammar, the execution of a set of non-conflict state transitions is interpreted by a sequence of graph transformations. This facilitates verifying a design model against system requirements. To demonstrate our approach, we present a case study on a toll-gate system.     

基于OPM/MAS 的钢铁企业多agent 生产调度模型

现有的面向agent建模方法在统一性、灵活性、交互能力、逻辑验证能力等方面存在很多不足,阻碍了多agent系统的研究和设计.为此,引入对象过程/多智能体系统(OPM/MAS)的建模方法,将系统的功能、结构和动态行为集成在统一的模型中,用图形和自然语言共同表达复杂系统的抽象概念,可进行逻辑验证,并具有灵活性强、表意清晰等优势.通过在钢铁企业生产调度中的应用,验证了OPM/MAS在多agent等复杂系统建模中的有效性.     

软件过程建模语言研究

本文介绍了软件过程建模的基本概念，提出了对软件过程建模语言的基本要求并简要介绍了几个有代表性的过程建模语言，给出了一个基于时序逻辑的形式化过程建模语言ＸＹＺ／ＰＭＥ，该语言是时序逻辑语言ＸＹＺ／Ｅ的子语言，它支持以角色为中心的逐步求精的过程建模方法，可在统一的形式框架内表示不同抽象级的过程模型．软件过程，软件过程建模，过程建模语言，时序逻辑，程序设计语言．     

A proposal for extending UML-B to support a conceptual model

UML-B is a development process framework for Event-B based on a “UML-like” graphical formal notation that provides support for object-oriented modelling concepts, in particular, for class and state machine diagrams. However, this methodology has a gap for mapping requirements to formal specifications. To overcome this issue, we present a proposal for extending UML-B to support a conceptual model to provide an easier starting point for the actual development process. More precisely, we propose two diagrams to facilitate the passing from requirements to the initial formal model: a first one to represent system behavior based on UML 2 interaction overview diagram (IOD) and a second one for system structure based on boundary-control-entity stereotyped class diagram (BCE). We show how to translate the former into an Event-B specification and explain how to link the latter to the original UML-B using a simple ATM example as proof of concept.     

面向问题的软件开发协同建模工具的研究与实现

建模软件是辅助需求工程师分析的工具,在需求设计阶段必不可少。目前,很少有需求建模工具可以跨平台运行,支持在线多用户协同以及验证需求模型正确性和完整性等功能。鉴于问题框架方法在需求工程领域获得了较大关注,文中开发了一款用户体验较好、兼容多平台的计算机辅助问题框架建模软件。本研究解决了自动化校验问题图的正确性和完整性以及复杂问题图拆分等难题,实现了用户登录、云端数据库存储设计和多人协同建模和验证,从而构建了一个在线需求建模、共享和验证的平台。     

双重软件体系结构描述框架XYZ/ADL

体系结构设计在软件开发过程中扮演着重要角色.工程中常用图形语言为软件体系结构建模,它们有直观、半形式化的优点;但是语义不够精确,难以对它们表示的模型进行分析,在这方面,形式化方法可与之互补.但在工程使用中仅用形式化语言建模又不太现实,所以如何结合二者之长以提高软件的可靠性已成为工业界和学术界共同关心的问题.提出了双重软件体系结构描述框架XYZ/ADL:支持工程中软件体系结构的基本概念,前端用一般的体系结构框图作为结构描述,用UML活动图、状态图作为抽象行为表示;后端用既可表示系统动态语义又可表示系统静态语义的时序逻辑语言XYZ/E作为一致的语义基础.前端的图形语言便于软件工程师的交流和使用,后端的形式语言是进一步的形式化分析验证的基础.     

Goal-driven risk assessment in requirements engineering

Risk analysis is traditionally considered a critical activity for the whole software system’s lifecycle. Risks are identified by considering technical aspects (e.g., failures of the system, unavailability of services, etc.) and handled by suitable countermeasures through a refined design. This, however, introduces the problem of reconsidering system requirements. In this paper, we propose a goal-oriented approach for analyzing risks during the requirements analysis phase. Risks are analyzed along with stakeholder interests, and then countermeasures are identified and introduced as part of the system’s requirements. This work extends the Tropos goal modeling formal framework proposing new concepts, qualitative reasoning techniques, and methodological procedures. The approach is based on a conceptual framework composed of three main layers: assets, events, and treatments. We use “loan origination process” case study to illustrate the proposal, and we present and discuss experimental results obtained from the case study.     

Correctly defined concrete syntax

Due to their complexity, the syntax of modern modeling languages is preferably defined in two steps. The abstract syntax identifies all modeling concepts whereas the concrete syntax should clarify how these concepts are rendered by graphical and/or textual elements. While the abstract syntax is often defined in form of a metamodel, there does not exist such standard format yet for concrete syntax definitions. The diversity of definition formats—ranging from EBNF grammars to informal text—is becoming a major obstacle for advances in modeling language engineering, including the automatic generation of editors. In this paper, we propose a uniform format for concrete syntax definitions. Our approach captures both textual and graphical model representations and even allows to assign more than one rendering to the same modeling concept. Consequently, following our approach, a model can have multiple, fully equivalent representations, but—in order to avoid ambiguities when reading a model representation—two different models should always have distinguishable representations. We call a syntax definition correct, if all well-formed models are represented in a non-ambiguous way. As the main contribution of this paper, we present a rigorous analysis technique to check the correctness of concrete syntax definitions.

Dynamic Meta Modeling with Time: Specifying the Semantics of Multimedia Sequence Diagrams

UML offers different diagram types to model behavior and dynamics of software systems. In some domains like embedded real-time systems or multimedia systems, it is necessary to include specifications of time since the correctness of these applications depends on the fulfillment of temporal requirements in addition to functional requirements. UML thus already incorporates language features to model time and temporal constraints. Such model elements must have an equivalent in the semantic domain. We have proposed Dynamic Meta Modeling (DMM) as a means for the specification of the formal operational semantics of UML models by applying graph transformation to the meta modeling of dynamic behavior. Within this paper, we extend this approach to also account for time by building on timed graph transformations. We apply these concepts to the domain of multimedia application modeling in which we adopt UML sequence diagrams. The DMM rules with time then specify an interpreter that can be used to analyze or test a model of multimedia sequence diagrams.     

支持复杂事件处理的业务流程建模研究

现有的流程建模语言缺少对复杂事件的支持.通过对BPMN进行扩展,提出一种事件的分层方法来表达业务过程中的基本事件和复杂事件.在此基础上进一步提出CE-BPM建模方法,并给出其形式化定义和图形化表示,增加了复杂事件和复杂事件处理网关的图形表示.最后通过实例来说明用BPMN建模时遇到的问题以及如何用CE-BPM建模解决问题的.     

面向航天嵌入式软件的形式化建模方法

航天嵌入式软件是航天型号任务成败的关键之一.航天嵌入式软件是一种周期性、多模式的软件.软件的每个模式表示系统处于一定的状态,并进行相应的复杂计算.因此,提出了一种名为SPARDL的形式化建模方法.为了满足型号应用的需求,对这一方法进行了若干改进.为了表达航天器的时序性质,提出了一种基于区间逻辑的性质规范语言.为了支持工业应用,还设计了代码生成方法.这一建模方法已在航天工业领域得到了应用.     

Comprehension and quality of analysis specifications—a comparison of FOOM and OPM methodologies

FOOM—Functional and Object Oriented Methodology—combines two essential software-engineering paradigms: the functional (or process-oriented) approach and the object-oriented (OO) approach. The two main products of the analysis phase of FOOM are an initial class diagram and OO-DFDs (dataflow diagrams including data classes rather than traditional data-stores). We evaluated these analysis products by comparing them with the analysis products of OPM—Object-Process Methodology—which also combines the functional and object-oriented approaches, using a unified diagrammatic notation. FOOM and OPM were compared in two controlled experiments from two main points of view: users and analysts. From the point of view of users we compared mainly comprehension of analysis specifications in each methodology. From the point of view of analysts we compared mainly quality, namely correctness of specifications created by analysts who utilized the two methodologies. The main results of the experiments are that FOOM specifications are more comprehensible and preferred by users, and that analysts create more correct specifications when using FOOM methodology.     

Safe design of high-performance embedded systems in an MDE framework

In this paper, we use the UML MARTE profile to model high-performance embedded systems (HPES) in the GASPARD2 framework. We address the design correctness issue on the UML model by using the formal validation tools associated with synchronous languages, i.e., the SIGALI model checker, etc. This modeling and validation approach benefits from the advantages of UML as a standard, and from the number of validation tools built around synchronous languages. In our context, model transformations act as a bridge between UML and the chosen validation technologies. They are implemented according to a model-driven engineering approach. The modeling and validation are illustrated using the multimedia functionality of a new-generation cellular phone.     

An Optimizing Compiler for Parallel Chemistry Simulations

Well designed domain specific languages have three important benefits: (1) the easy expression of problems, (2) the application of domain specific optimizations (including parallelization), and (3) dramatic improvements in productivity for their users. In this paper we describe a compiler and parallel runtime system for modeling the complex kinetics of rubber vulcanization and olefin polymerization that achieves all of these goals. The compiler allows the development of a system of ordinary differential equations describing a complex vulcanization reaction or single-site olefin polymerization reaction—a task that used to require months—to be done in hours. A specialized common sub-expression elimination and other algebraic optimizations sufficiently simplify the complex machine generated code to allow it to be compiled—eliminating all but 8.0% of the operations in our largest program and enabling over 60 times faster execution on our largest benchmark codes. The parallel runtime and dynamic load balancing scheme enables fast simulations of the model.     

基于Spin的SysML活动图验证框架

系统建模语言（systems modeling language,SysML）缺乏精确的形式化分析和验证手段,造成模型存在死锁、活锁等诸多问题,可以通过形式化验证方法来提高模型的正确性。然而,受制于传统的形式化方法需要复杂的公式推理,并且不易理解等方面局限性,大多数验证仅限专家使用并且很耗时。为了克服SysML模型中存在的问题,提出了一种针对SysML多层次活动图的分析验证框架。它可以根据已构建的模型,将多层次活动图分解转换为Spin的输入模型,并对相关子图进行重组和验证。实验表明,该方法可以有效识别多层次活动图,并准确实施转换,为模型验证的演化提供支持。