基于容器中间件的组件系统体系结构性能评价

对组件系统性能建模时,需要考虑中间件平台的影响.基于体系结构模式,分析了容器风格中间件对组件系统结构和性能的影响,并提出了一种在组件系统UML描述中集成中间件组件及交互关系的方法.从该集成UML模型导出的性能模型,能够有效地反映中间件的影响.这样,在对组件系统性能建模时,无须了解中间件内部细节.这种基于体系结构模式的方法可以方便扩展以处理不同风格的中间件,且易于实现自动化.以EJB容器中间件为例说明并验证了所提出方法的有效性.     

基于图文法的动态软件体系结构支撑环境

使用类型化的属性图及其图文法来直观而形式地刻画软件体系结构和体系结构风格,用图转换来刻画动态体系结构的重配置行为.基于这种刻画,构建了一个动态软件体系结构支撑环境.该环境一方面,通过一个基于图文法的编辑器来支持体系结构图模型的可视化构造和操纵;另一方面,基于内置运行时体系结构技术实现了体系结构图模型在具体系统中的物理实施,并使得图模型上的图转换操作可以自动映射到实际系统的动态重配置上.再加上一系列的辅助设施,形成了一个较为完整的基于图文法的动态软件体系结构支撑环境.     

基于模式的软件体系结构建模

文中给出了一种应用程序组件的领域建模方法,将组件静态方面的面向对象建模(类图)、组件行为或功能等动态方面的基于模式的建模(模式实例模型)与代码生成实现技术结合起来。并试图用模式描述组件体系结构风格,指导如何构造和组织一个系统。基于模式的软件体系结构设计方法可在很短的时间内创建各种组件,并通过改变模型中的抽象体系结构特性来满足应用程序中的体系结构要求,因而该方法是切实可行的。     

基于组件模型分析的组件容器产品线体系结构

组件容器为组件提供部署和运行环境,是基于组件分布式应用开发的核心.近年来分布式组件的多样化和快速演化对组件容器的开发方法提出了挑战.产品线工程是基于公共的核心资产开发特定领域内软件产品系列的软件工程方法,产品线体系结构是其中最重要的部分.进行组件容器产品线体系结构的研究能够提高组件容器的结构复用性,获得更高的生产效率和质量.由于组件模型是组件容器设计的基础,在领域分析阶段引入组件模型分析,提出了组件模型分析框架,通过组件模型元素到领域需求元素的映射,建立组件容器领域模型.提出了组件容器设计的基本原则,并根据变化性封装原则,提出了组件容器产品线体系结构PLACE,通过引入可选属性、模块层次结构和决策模型,实现组件容器的领域需求.PLACE产品线体系结构已在网驰平台的多个组件容器设计中得到应用.     

形式化方法描述管道过滤器软件体系结构

体系结构形式化描述能为系统设计提供精确和抽象的模型,通过这个模型来分析体系结构的构成,分解和约束特征.利用形式化方法来描述软件体系结构中常见的管道过滤器风格.     

Pro/ENGINEER运动仿真教程(2)

第2章连接定义 一、连接的概念及分类 连接就是把元件与元件、元件与组件通过一定的运动副装配在一起,并限制二者的自由度,从而在二者之间建立一个确定的运动关系.在Pro/ENGINEER Wildfire的装配模块中共有8种连接方式,如表1所示.     

基于COM技术的通用标图组件的设计与实现

按照组件式软件开发的思想,首先提出了一种通用标图组件的应用体系结构,并以COM技术为基础设计出组件的功能接口及其与底图模块的连接方式,依据高内聚、低耦合的原则,提出了一种将功能调用接口与细节实现分离的实施方案,具有体积小巧、运行高效的优点。最后给出两个应用实例以验证该组件的实用性与灵活性。     

基于实时组件的可重构数控系统研究

针对可重构数控系统存在的行为与定时问题，将调度机制引入基于口的组件，提出一种实时组件模型，并以此为基础建立了层次化多模式的数控系统体系结构。该结构通过层次化有限自动机描述系统的控制行为；通过组件网络刻画系统的定时特性，为分析可重构控制器构形的变化提供了有效的手段。针对2轴控制器的重构过程有效地验证了文中方法的有效性。     

一种基于PLM系统的软件体系结构风格的研究

一个良好的软件体系结构对一个应用软件系统起着决定性的作用.软件体系结构风格决定着一个系统的软件体系结构.本文通过比较C/S和正交两种常见的软件体系结构风格,指出这两种体系结构风格可以混合使用,并给出基于PLM系统的实例.     

组件化模具PDM系统的组件结构与规划

对组件进行系统合理地规划是基于组件技术开发PDM系统的PDM系统提出了更高的要求.为此,从系统规划的角度提出了组件化模具PDM系统的组件层次体系结构,对系统组件进行了详细地划分,最后引入GenVoca模型对组件间关系进行形式化描述,保证了组件之间逻辑关系的正确性.     

Rule-based systems formalized within a software architectural style

This article considers the utilization of architectural styles in the formal design of knowledge-based systems. The formal model of a style is an approach to systems modeling that allows software developers to understand and prove properties about the system design in terms of its components, connectors, configurations, and constraints. This allows commonality of design to be easily understood and captured, leading to a better understanding of the role that an architectural abstraction would have in another complex system, embedded context, or system integration. In this article, a formal rule-based architectural style is presented in detail using the Z notation. The benefits of depicting the rule-based system as an architectural style include reusability, understandability, and the allowance for formal software analysis and integration techniques. The ability to define the rule-based architectural style in this way, illustrates the power, clarity, and flexibility of this specification form over traditional formal specification approaches. In addition, it extends current verification approaches for knowledge-based systems beyond the knowledge base only.     

软件复合连接件的形式化研究

基于构件的软件开发是软件开发的主流范型。构件通过连接件进行连接和交互。连接件是软件系统设计的一阶实体(First-class Entities),是决定软件系统功能和质量的重要因素。伴随软件系统和构件的规模及复杂程度日益增加,连接件变得愈加复杂和多样。因此,需要运用增量、合成的方法开发和支持复杂的连接件。本文提出一种根据已有连接件合成新连接件的形式化方法。该方法的特点是定义连接件合成的基本方式,即连接件运算符,组合运用连接件运算符合成复杂的连接件。并基于Wright连接件的形式化规约,给出了谊复合连接件形式化规约的生成算法。     

A methodology for architecture-level reliability risk analysis

The paper presents a methodology for reliability risk assessment at the early stages of the development lifecycle, namely, the architecture level. We describe a heuristic risk assessment methodology that is based on dynamic metrics. The methodology uses dynamic complexity and dynamic coupling metrics to define complexity factors for the architecture elements (components and connectors). Severity analysis is performed using Failure Mode and Effect Analysis (FMEA) as applied to architecture models. We combine severity and complexity factors to develop heuristic risk factors for the architecture components and connectors. Based on analysis scenarios, we develop a risk assessment model that represents components, connectors, component risk factors, connector risk factors, and probabilities of component interactions. We also develop a risk analysis algorithm that aggregates risk factors of components and connectors to the architectural level. Using the risk aggregation and the risk analysis model, we show how to analyze the overall risk factor of the architecture as the function of the risk factors of its constituting components and connectors. A case study of a pacemaker architecture is used to illustrate the application of the methodology. The methodology is used to identify critical components and connectors and to investigate the sensitivity of the architecture risk factor to changes in the heuristic risk factors of the architecture elements     

Software architectural patterns in practice: an empirical study

Software architecture involves a series of decisions based on many factors in a wide range of software development. Architects face recurring issues in different software architecture design, and to reduce huge cost and risks, software architecture decisions can rely on a set of idiomatic patterns commonly named architectural styles or patterns. Architectural pattern determines the vocabulary of components and connectors that are used in instances of the pattern together with a set of constraints to combine the two. Little contemporary data exists to document actual practices used by software professionals when selecting and incorporating architectural patterns for their projects in industry. Therefore, a comprehensive survey of software professionals was conducted to attempt to discover these practices. This exploratory survey and its quantitative results offer opportunities for further interpretation and comparison. Data from this survey are presented in this paper and include characteristics of projects, practices, organizations, and practitioners related to the usage of architectural patterns. Some of the notable findings include that architectural patterns are widely used in software projects with the Model–View–Controller being the most common. Despite reported difficulties in incorporating architectural patterns, the majority of the software professionals revealed that patterns were the most essential for completing the projects. The most difficult pattern to implement and the most expensive to adopt was the peer-to-peer, while the easiest was the client–server.

     

基于体系结构依赖图的Wright形式化语言的切片方法

将切片技术应用于软件体系结构中,根据程序依赖图和系统依赖图的构建思想,提出了体系结构元素依赖图(SADG)的概念,并给出了构建方法以及基于依赖图的切片算法。利用此切片技术从已有的软件体系结构的Wright描述中,提取使用者感兴趣的软件元素(例如,构件和连接体),从而从体系结构的角度,更好的支持了软件理解、软件维护、软件再工程以及软件复用。     

连接件模型与分类研究

连接件对于基于软件体系结构的软件开发具有重要意义,该文根据连接件在软件体系结构中所承担的责任以及它对构件交互的支持,建立了连接件模型,进而根据软件开发中的连接实现以及软件体系结构风格的研究,对连接件进行了分类,包括过程调用等11类连接件,不同类型的连接件支持不同的实现映射和复用途径。     

Classifying architectural constraints as a basis for software quality assessment

Architectural styles and patterns have been studied since the inception of software architecture as a discipline. We generalise architectural styles, patterns and similar concepts by introducing the notion of architectural constraints. An architectural constraint is a vehicle for the reuse of architectural design knowledge and for the improvement of software quality. It may be used for improving architectural analyses of quality characteristics of the software system to be realised. We present the method for surveying the literature on architectural constraint concepts, and provide a taxonomy covering various definitions of architectural styles and patterns.