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     

GO法在软件体系结构可靠性分析中的应用

GO法是一种系统可靠性分析方法,可将GO法应用到软件体系结构的可靠性分析中。根据软件体系结构自身的特点及构件之间的关系,分别建立了软件体系结构六种基本结构的GO模型,并进行了定量GO运算。通过一个实例,说明了应用GO法对软件体系结构的可靠性进行分析的全过程。实践表明:运用定量GO运算能够方便地计算出整个软件体系结构的可靠度,通过定性GO分析还可评估各构件及连接件的重要性,对后期系统的设计与开发具有一定的指导意义。     

一种UML 软件架构性能预测方法及其自动化研究

软件性能需求作为软件质量需求的重要组成部分,已受到人们极大的重视.而只在软件开发周期后期才重点关注软件性能需求的传统软件开发方法,将给开发者带来高风险和高成本等后果.如果能在软件开发周期的早期对软件系统性能进行预测,可以提前发现软件系统架构存在的性能瓶颈,并找出可能的优化方案,对各种设计方案进行比较以得出最优的软件系统架构.研究了一种基于模型的UML 软件架构性能预测方法:该方法选取软件架构设计中的UML 用例图、活动图和构件图,并引入构造型和标记值,将它们扩展为UML SPT 模型;进而,通过转换算法将UML SPT 模型转换为排队网络模型,该算法可处理同时包含分支节点和汇合节点的UML 模型活动图;最后,利用频域分析理论求解排队网络模型,以得出性能参数及性能瓶颈.同时介绍了UML 软件架构性能自动化工具的设计方案,并给出了软件架构性能预测实例.     

An architecture process maturity model of software product line engineering

Software architecture has been a key research area in the software engineering community due to its significant role in creating high-quality software. The trend of developing product lines rather than single products has made the software product line a viable option in the industry. Software product line architecture (SPLA) is regarded as one of the crucial components in the product lines, since all of the resulting products share this common architecture. The increased popularity of software product lines demands a process maturity evaluation methodology. Consequently, this paper presents an architecture process maturity model for software product line engineering to evaluate the current maturity of the product line architecture development process in an organization. Assessment questionnaires and a rating methodology comprise the framework of this model. The objective of the questionnaires is to collect information about the SPLA development process. Thus, in general this work contributes towards the establishment of a comprehensive and unified strategy for the process maturity evaluation of software product line engineering. Furthermore, we conducted two case studies and reported the assessment results, which show the maturity of the architecture development process in two organizations.     

基于排队网络的VoIP信令解析系统性能分析

基于软件性能模型的软件性能评估可以应用在软件研发周期的早期阶段,以便对软件系统的行为进行定量分析。该文给出一种应用排队网络模型对VoIP信令解析软件体系结构性能的评估方法。该方法的基本思想是：从基于UML描述的活动图导出多类排队网络性能模型,通过统计分析将得出的性能参数反馈给UML软件体系结构模型,不断完善体系结构设计。模型提供的统计性能评估方法克服了受限估计离散事件分析的局限性。     

基于UML的GRAPPLE在数字化医院信息系统设计中的应用

UML(标准建模语言)是一种定义良好、易于表达、功能强大且普遍适用的建模语言,是开发软件系统分析和设计阶段的重要工具。GRAPPLE是一个可自适应的、灵活的开发过程方法学,本文以数字化医院信息系统的系统分析和设计为例,介绍了结合UML建模的GRAPPLE的实际开发过程。     

An acceptability estimation and analysis methodology based on Bayesian networks

As companies are forced to conceive innovative products to stay competitive, designers face the challenge of developing products more suited to users' needs and perceptions in order to be accepted, thus reducing project risk failure. Evaluating users' acceptability has become an important research problem. Current approaches leave the acceptance evaluation question to be answered in the last stages of product development process (NPD), when an almost finished prototype is available and when there is no time left for important modifications. Acceptability evaluation methods suitable for use from the early stages of the NPD process are thus needed. This paper proposes a method for acceptability evaluation and analysis that can be used in the early stages of the development cycle. It is based on the evaluation of the solution concept by the users. The relationships among the factors (or criteria) are made explicit, thus helping designers to identify the key factors for acceptance. As the users' tests and the maturity of the concept prototype are limited in this stage, the proposed method exploits the inference properties of Bayesian networks making it possible to make useful estimations and allowing the exploration of actions that could improve the product acceptability level. Two case studies are presented in order to illustrate the method, the first related to a technological product design for a home-health care service provider and the second to a work-related musculoskeletal disorder prevention software design.Relevance to industryThe article describes an acceptability assessment and an analysis approach to be used by industrial engineers, designers and ergonomists in the early phases of design projects. The method can help the design team to identify the levers (key factors) for enhancing product acceptance and to identify different actions (e.g. product modification, deployment strategy, and training).     

探讨基于UML的软件体系结构开发方法

在软件工程领域中,必须对软件体系结构进行系统准确的开发,才能保证软件系统的独特性、科学性与智能性。ADL作为一种常用的描述语言,虽然在一些体系结构语言中能够进行一定的定义与开发,但目前仍然很难和主流的开发方法集成在一起。而随着软件技术的不断发展,UML已经逐渐被工业界认可。从UML软件系统的4种模型入手,利用实例的分析方法,从而使大家能对UML的相关技术有进一步的了解。     

An Introduction to Software Testing

The development of large software systems is a complex and error prone process. Faults might occur at any development stage and they must be identified and removed as early as possible to stop their propagation and reduce verification costs. Quality engineers must be involved in the development process since the very early phases to identify required qualities and estimate their impact on the development process. Their tasks span over the whole development cycle and go beyond the product deployment through maintenance and post mortem analysis. Developing and enacting an effective quality process is not a simple task, but it requires that we integrate many quality-related activities with product characteristics, process organization, available resources and skills, and budget constraints.This paper discusses the main characteristics of a good quality process, then surveys the key testing phases and presents modern functional and model-based testing approaches.     

Tropos: An Agent-Oriented Software Development Methodology

Our goal in this paper is to introduce and motivate a methodology, called Tropos,¹ for building agent oriented software systems. Tropos is based on two key ideas. First, the notion of agent and all related mentalistic notions (for instance goals and plans) are used in all phases of software development, from early analysis down to the actual implementation. Second, Tropos covers also the very early phases of requirements analysis, thus allowing for a deeper understanding of the environment where the software must operate, and of the kind of interactions that should occur between software and human agents. The methodology is illustrated with the help of a case study. The Tropos language for conceptual modeling is formalized in a metamodel described with a set of UML class diagrams.     

基于UML的软件体系结构的定量评估

软件体系结构是软件开发过程的关键制品,应该尽早地分析和评估其质量.目前研究的软件体系结构评估主要集中在基于场景的评估方法,其特点是定性的、主观的、无需专用的体系结构描述语言.本文提出以统一建模语言UML作为软件体系结构描述语言以及度量的软件体系结构的定量评估.针对UML的可视化、多视图、半形式化以及一致地应用在整个软件开发活动的特性,提出一组UML度量,从UML图所表达的信息含量、可视化影响以及图形建模元素之间的关联性这三个方面度量软件体系结构.分析并讨论这组UML度量在评估软件体系结构的规模、复杂性和结构性等质量属性方面的应用.     

A holistic architecture assessment method for software product lines

The success of architecture-centric development of software product lines is critically dependent upon the availability of suitable architecture assessment methods. While a number of architecture assessment methods are available and some of them have been widely used in the process of evaluating single product architectures, none of them is equipped to deal with the main challenges of product line development. In this paper we present an adaptation of the Architecture Tradeoff Analysis Method (ATAM) for the task of assessing product line architectures. The new method, labeled Holistic Product Line Architecture Assessment (HoPLAA), uses a holistic approach that focuses on risks and quality attribute tradeoffs – not only for the common product line architecture, but for the individual product architectures as well. In addition, it prescribes a qualitative analytical treatment of variation points using scenarios. The use of the new method is illustrated through a case study.     

Generating Natural Language specifications from UML class diagrams

Early phases of software development are known to be problematic, difficult to manage and errors occurring during these phases are expensive to correct. Many systems have been developed to aid the transition from informal Natural Language requirements to semi-structured or formal specifications. Furthermore, consistency checking is seen by many software engineers as the solution to reduce the number of errors occurring during the software development life cycle and allow early verification and validation of software systems. However, this is confined to the models developed during analysis and design and fails to include the early Natural Language requirements. This excludes proper user involvement and creates a gap between the original requirements and the updated and modified models and implementations of the system. To improve this process, we propose a system that generates Natural Language specifications from UML class diagrams. We first investigate the variation of the input language used in naming the components of a class diagram based on the study of a large number of examples from the literature and then develop rules for removing ambiguities in the subset of Natural Language used within UML. We use WordNet, a linguistic ontology, to disambiguate the lexical structures of the UML string names and generate semantically sound sentences. Our system is developed in Java and is tested on an independent though academic case study.     

A business maturity model of software product line engineering

In the recent past, software product line engineering has become one of the most promising practices in software industry with the potential to substantially increase the software development productivity. Software product line engineering approach spans the dimensions of business, architecture, software engineering process and organization. The increasing popularity of software product line engineering in the software industry necessitates a process maturity evaluation methodology. Accordingly, this paper presents a business maturity model of software product line, which is a methodology to evaluate the current maturity of the business dimension of a software product line in an organization. This model examines the coordination between product line engineering and the business aspects of software product line. It evaluates the maturity of the business dimension of software product line as a function of how a set of business practices are aligned with product line engineering in an organization. Using the model presented in this paper, we conducted two case studies and reported the assessment results. This research contributes towards establishing a comprehensive and unified strategy for a process maturity evaluation of software product lines.     

An organizational maturity model of software product line engineering

Software product line engineering is an inter-disciplinary concept. It spans the dimensions of business, architecture, process, and the organization. Some of the potential benefits of this approach include cost reduction, improvements in product quality and a decrease in product development time. The increasing popularity of software product line engineering in the software industry necessitates a process maturity evaluation methodology. Accordingly, this paper presents an organizational maturity model of software product line engineering for evaluating the maturity of organizational dimension. The model assumes that organizational theories, behavior, and management play a critical role in the institutionalization of software product line engineering within an organization. Assessment questionnaires and a rating methodology comprise the framework of this model. The objective and design of the questionnaires are to collect information about the software product line engineering process from the dual perspectives of organizational behavior and management. Furthermore, we conducted two case studies and reported the assessment results using the organizational maturity model presented in this paper.