可信软件非功能需求形式化表示与可满足分析

可信软件的可信性由其功能需求和非功能需求共同来体现,其中,非功能需求的实现是可信软件获得用户对其行为实现预期目标能力的信任程度的客观依据.针对可信软件的重要性以及对可信软件的迫切需求,在可信软件的早期需求工程阶段,提出可信软件非功能需求驱动的过程策略选取方法.首先,对可信软件需求进行定义,提出由功能需求和非功能需求中的可信关注点构成可信需求,非可信关注点的非功能需求则定义为软目标,用于表达质量需求,基于模糊集合论和信息熵对可信软件非功能需求进行排序并获取可信关注点和软目标.在此基础上,提出可信软件非功能需求驱动的过程策略选取方法.传统的软件早期需求工程阶段的目标是为了获取满足需求的技术及设计决策,与此不同,本文对可信软件非功能需求进行分析的目标是获取过程策略,从过程角度解决可信软件生产问题.由于非功能需求间复杂的相关关系,尤其是因为存在冲突关系,故提出了基于可满足性问题求解方法推理过程策略的方法,选取满足可信软件非功能需求的过程策略.最后,通过第三方可信认证中心软件的案例,说明所提出方法的可行性.     

Quality requirements engineering for systems and software architecting: methods, approaches, and tools

Requirements engineering and software architecture are quite mature software engineering sub-disciplines, which often seem to be disconnected for many reasons and it is difficult to perceive the impact of functional and non-functional requirements on architecture and to establish appropriate trace links for traceability purposes. In other cases, the estimation of how non-functional requirements, as the quality properties a system should pose, is not perceived useful enough to produce high-quality software. Therefore, in this special issue, we want to highlight the importance and the role of quality requirements for architecting and building complex software systems that in many cases require multidisciplinary engineering techniques, which increases the complexity of the software development process.     

一个表示和运用非功能性需求的框架

本文分析了一个软件开发进程中表示和运用非功能性需求的综合框架，该框架的目的是开发一套技术以调整软件开发进程中的设计决策，从而强调了依据非功能需求，探索合理化的软件开发进程。     

Non-functional requirements in the software development process

The satisfaction of a customer's non-functional requirements is an important factor in determining the acceptince of a designed system. They can be seen as constraints on either the final product or on the development process. Each such requirement may generate further constraints, depending on decisions taken, forming a graph, and a path can be traced between the original requirement and a design commitment. Work has been carried out on modelling where in the development process such decisions are best taken using Milner's Calculus of Communicating Systems, with agents representing roles and documents. A prototype support environment based on the model is being implemented using C and Motif.     

There's Nothing Like a Good Argument ...

Since computing pioneers Vannevar Bush and Doug Engelbart envisioned computational support for argumentation, many have pursued the exciting vision of tools for capturing and augmenting collective reasoning. Designers would be able to capture their deliberations on the fly during design sessions, with intuitive visualizations assisting participatory analysis by diverse stakeholders. These traces would later help recover design rationale. When managing requirements, we can think of argument schemes as reusable patterns for tightening up deliberations. Project reviews are an obvious candidate, where decisions must be justified, often to be signed off, and resources committed. As meeting capture becomes a practical reality, we have the basis for requirements platforms that provide new forms of multimedia requirements and rationale traceability.     

Managing requirements inconsistency with development goal monitors

Managing the development of software requirements can be a complex and difficult task. The environment is often chaotic. As analysts and customers leave the project, they are replaced by others who drive development in new directions. As a result, inconsistencies arise. Newer requirements introduce inconsistencies with older requirements. The introduction of such requirements inconsistencies may violate stated goals of development. In this article, techniques are presented that manage requirements document inconsistency by managing inconsistencies that arise between requirement development goals and requirements development enactment. A specialized development model, called a requirements dialog meta-model, is presented. This meta-model defines a conceptual framework for dialog goal definition, monitoring, and in the case of goal failure, dialog goal reestablishment. The requirements dialog meta-model is supported in an automated multiuser World Wide Web environment, called DEALSCRIBE. An exploratory case study of its use is reported. This research supports the conclusions that: an automated tool that supports the dialog meta-model can automate the monitoring and reestablishment of formal development goals; development goal monitoring can be used to determine statements of a development dialog that fail to satisfy development goals; and development goal monitoring can be used to manage inconsistencies in a developing requirements document. The application of DEALSCRIBE demonstrates that a dialog meta-model can enable a powerful environment for managing development and document inconsistencies     

中文非功能需求描述的识别与分类方法研究

非功能需求描述系统质量相关的属性,是软件设计决策的重要依据和评估标准.与功能需求的描述相比,非功能需求描述通常比较分散,且往往是隐含的.当采集到的需求原始描述内容较多时,逐一进行人工判别和整理需要耗费大量的时间和精力.针对中文自然语言描述的需求文本,提出了自动化的非功能需求识别和分类方法.其中,识别过程旨在从文本中提取出可能包含非功能需求的语句,尽可能地缩小人工检查的范围.分类过程则进一步将包含非功能需求的语句划分到性能、可靠性、可用性、安全性、可维护性这五大类非功能需求类型之中.分类训练和实验测试基于课题组工作项目整理的实验数据集进行,最终,基于一个工业界的实际应用案例数据,验证了方法的有效性.     

Requirements traceability in model-driven development: Applying model and transformation conformance

The variety of design artifacts (models) produced in a model-driven design process results in an intricate relationship between requirements and the various models. This paper proposes a methodological framework that simplifies management of this relationship, which helps in assessing the quality of models, realizations and transformation specifications. Our framework is a basis for understanding requirements traceability in model-driven development, as well as for the design of tools that support requirements traceability in model-driven development processes. We propose a notion of conformance between application models which reduces the effort needed for assessment activities. We discuss how this notion of conformance can be integrated with model transformations.     

An evaluation of timed scenario notations

There is a general consensus on the importance of good Requirements Engineering (RE) for achieving high quality software. The modeling and analysis of requirements have been the main challenges during the development of complex systems. Although semi-formal, scenario driven approaches have raised the awareness and use of requirement engineering techniques, mostly because of their intuitive representation. Scenarios are a well established approach to describe functional requirements, uncovering hidden requirements and trade-offs, as well as validating and verifying requirements.The ability to perform quantitative analysis at the requirements level supports the detection of design errors during the early stages of a software development life cycle, and helps reduce the cost of later redesign activities. In order to achieve this goal, non-functional aspects and in particular time-related aspects have to be incorporated at the software requirement phase. This is essential in order to correctly model and analyze time dependent applications at early stages in system development.The widespread interest in time modeling and analysis techniques provides the major motivation for our paper. The objective of the article is to provide readers with sufficient knowledge about existing timed scenario approaches to guide them in making informed decisions to when and how time aspects can be incorporated in their development process. In order to support this process, we present a comprehensive classification, evaluation and comparison of time-based scenario notations. In order to evaluate these existing notations, we introduce a set of eleven time-related criteria and apply them to categorize and compare forty seven scenario construction approaches.     

The socio-economics of software architecture

The paper argues that strategic decisions about software architectures need to be based on a social and economic analysis of which designs are likely to succeed and become accepted by users. Software architecture is increasingly having to take account of customisation, reuse, end-user development and system configuration. The relationship between architecture and end users’ requirements is investigated, to propose a cost-benefit framework to support reasoning about architectural choices from the perspective of end users. The relationships between architectural decisions and non-functional requirements is reviewed, and the impact on architecture is assessed using a case study of developing configurable, semi-intelligent software to support medical researchers in e-science domains.     

基于面向方面MDA的实时系统开发方法

实时系统有许多难以处理的横切整个系统的非功能需求。针对以上问题,提出基于面向方面模型驱动架构的实时系统开发方法。该方法在设计阶段将系统的非功能需求从功能需求中分离出,以降低系统开发的复杂性,提高系统的可重用性、可维护性和横切关注点的模块化程度。通过应用实例证明该方法是有效的。     

面向方面的软件非功能特性研究

软件非功能特性的处理一直以来都是困扰着研究人员和开发人员的难题。将面向方面的编程思想运用于软件非功能性的研究打破了传统的软件设计过程,这种研究方法在软件需求分析的初期分离出系统的非功能特性并将这些非功能特性做一个整体的处理,加快了软件开发的进度,提高了生产效率。文中基于面向方面思想,利用著名的非功能特性描述框架NFR对软件非功能特性进行描述,解决了软件关注点组合时产生的冲突问题,为软件非功能特性的处理提供了很好的解决办法。     

软件非功能需求权衡代价

软件非功能需求的实现涉及软件质量这一重要问题,非功能需求的满足程度,直接影响软件质量的满足程度.针对一直以来对软件质量的一贯重视以及软件非功能需求权衡的重要性,借鉴微观经济学领域的生产理论、替代弹性原理和线性规划方法,提出了软件非功能需求权衡代价分析方法并开发了辅助工具.首先,对项目组前期完成的可信软件非功能需求可满足性分析方法进行改进,提出了利益相关者通过协商获取非功能需求评估数据的方法,建立了非功能需求本体概念并构建本体知识库;针对实现非功能需求的策略,使用前期已完成的策略推理方法,对推理产生矛盾的策略提出权衡代价分析方法;通过分析策略实施代价,为软件开发及演化提供具有实际可操作的权衡决策依据,从更加符合产业化需要的角度解决软件非功能需求权衡问题;最后,基于可信第三方认证中心软件案例的维护及演化需要,对推理出矛盾的策略进行权衡代价分析,并给予决策建议,说明所提出方法的可行性.     

Requirement-oriented risk management for incremental software development

In incremental software development (ISD) functionalities are delivered incrementally and requirements keep on evolving across iterations. The requirements evolution involves the addition of new dependencies and conflicts among functional and non-functional requirements along with changes in priorities and dependency weights. This, in turn, demands refactoring the order of development of system components to minimize the impact of these changes. Neglecting the non-functional constraints in the software development process exposes it to risks that may accumulate across several iterations. In this research work, we propose a risk management framework for ISD processes that provides an estimate of risk exposure for the project when functional features are frozen while ignoring the associations with non-functional requirements. Our framework proposes suitable risk reduction strategies that work in tandem with the risk assessment module. We also provide a tool interface for our risk management framework.

     

Documenting after the fact: Recovering architectural design decisions

Software architecture documentation helps people in understanding the software architecture of a system. In practice, software architectures are often documented after the fact, i.e. they are maintained or created after most of the design decisions have been made and implemented. To keep the architecture documentation up-to-date an architect needs to recover and describe these decisions.This paper presents ADDRA, an approach an architect can use for recovering architectural design decisions after the fact. ADDRA uses architectural deltas to provide the architect with clues about these design decisions. This allows the architect to systematically recover and document relevant architectural design decisions. The recovered architectural design decisions improve the documentation of the architecture, which increases traceability, communication, and general understanding of a system.     

QoS需求驱动的服务配置框架

为支持服务质量敏感的基于组件的分布式应用的开发,中间件需要为组件提供并配置各种服务质量服务的非功能性属性.目前的组件架构提供的服务配置方式大多是静态的,且没有考虑不同客户的需求.在对EJB架构进行研究的基础上,提出一种服务质量需求驱动的服务配置框架.研究了根据客户的服务质量需求,在组件实例级别自动生成服务配置决策并实施,实现对不同客户服务差分处理.框架是一个基于服务配置的决策模型,通过多选择背包问题生成服务配置策略.最后通过一个应用实例对框架进行了验证.     

功能需求到测试用例的可追溯性研究

软件开发主要由需求收集、设计、实现、测试和维护等几个阶段构成,其中维护始终是主要开销。在维护阶段,开发人员必须理解程序才能定位缺陷,而系统的需求和源代码、测试用例等之间的可追溯性连接能帮助减少开发人员在理解程序时的工作量。研究现有的功能定位技术和可追溯性方法,通过对现有方法的改进,提出了一种集成动态执行信息和IR技术的方案来建立需求到测试用例的可追溯性连接,用以辅助开发人员在维护阶段的工作。     

Non-functional requirements analysis: deficiencies in structured methods

This paper examines some deficiencies in structured systems development methods that have the effect of overlooking non-functional requirements. Evidence from four case studies shows that non-functional requirements are often overlooked, questioning users is insufficient, methodologies do not help in the elicitation of non-functional requirements and there is a lack of consensus about the meaning and utility of non-functional requirements. Some lessons are drawn from the domain of real time systems development. Finally a framework is advanced for taking a stakeholder approach to the conflict and organisational change issues associated with the elicitation stage of requirements analysis.     

基于MBSE的PHM开发平台设计

故障预测与健康管理(PHM)开发平台具有结构功能复杂的特点,传统的设计方法难以保证其结构合理性与功能可靠性.针对传统的基于文本的系统设计中存在的需求追溯性弱、问题描述模糊的问题,提出了应用基广模型的系统工程(MBSE)方法论指导平台设计过程,使用模型驱动的OOSEM建模方法对PHM开发平台进行模型搭建.通过利益相关者需...     

RFID enabled traceability networks: a survey

The emergence of radio frequency identification (RFID) technology brings significant social and economic benefits. As a non line of sight technology, RFID provides an effective way to record movements of objects within a networked RFID system formed by a set of distributed and collaborating parties. A trail of such recorded movements is the foundation for enabling traceability applications. While traceability is a critical aspect of majority of RFID applications, realizing traceability for these applications brings many fundamental research and development issues. In this paper, we assess the requirements for developing traceability applications that use networked RFID technology at their core. We propose a set of criteria for analyzing and comparing the current existing techniques including system architectures and data models. We also outline some research opportunities in the design and development of traceability applications.