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.     

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.     

一种通过量化分析实现非功能需求的方法

提供了一种面向过程非功能需求处理方法，通过量化需求领域信息实现；对非功能需求目标进行分析得到目标优化树，在目标优化树中加入领域信息产生设计分析图，然后对图中领域信息结点进行量化赋以特定的量值，权衡各量值来选择合适的解决方案，还提供了简便的方法来支持系统升级。     

一种通过量化分析实现非功能需求的方法

提供了一种面向过程非功能需求处理方法，通过量化需求领域信息实现；对非功能需求目标进行分析得到目标优化树，在目标优化树中加入领域信息产生设计分析图，然后对图中领域信息结点进行量化赋以特定的量值，权衡各量值来选择合适的解决方案，还提供了简便的方法来支持系统升级。     

可信软件非功能需求可满足性经济学方法分析

针对软件可信性的重要性以及非功能需求的策略选取对软件可信性的影响,提出了一种在早期需求工程阶段将用于辅助决策的经济学和需求工程相结合的方法,并提出了可信软件非功能需求可满足性的策略选取框架,以辅助策略选取。首先,对功能需求及经济学方法概念进行了定义和转换,例如,将软件开发过程中的非功能需求看作经济学生产过程中的生产要素、软件的利益相关者看作生产过程中的生产者等;并定义了非功能需求分解模型。在此基础上,基于模糊集合论和信息熵对软件非功能需求进行模糊排序从而获取利益相关者的关键非功能需求,并利用经济学中生产过程的相关方法计算使用策略的可信性效益,辅助策略的选取。以移动基础维护管理平台为例,使用提出的方法,说明了所提方法的可行性。     

基于回答集语义复杂信息系统表单驱动需求规约的描述与验证

高品质的复杂信息系统软件设计与开发源自合理的、完整的和准确的软件需求.为了描述需求领域的非确定问题,并在需求获取不完全的情况下对需求规约进行非单调推理,本文将回答集逻辑程序和基于因果关系的动作理论应用于需求描述与验证.针对复杂信息系统需求问题空间规模较大的特点,将动作描述语言C与动作查询语言Q结合形成动作语言Lo,作为需求描述的基础;通过分析需求领域各个元素及其相互关系,以表单驱动引导需求,并作为需求描述依据与核心,提出了描述需求问题空间静态关系和动态行为关系的“主谓宾状”需求模型MRspoa.利用回答集逻辑程序求解器SMODELS,可以对需求规约进行多层次规划与检测.本文的研究来自工程项目实践的总结与提高,研究成果得到具体应用.     

需求描述前的需求跟踪模型研究

对需求描述前的需求进行跟踪可以减少需求错误、有助于需求变更的处理和软件组织的过程改进。针对传统需求跟踪方法没有对需求描述前的需求跟踪提供合适支持的问题，文章剖析了需求分析过程中产生的中间产品及其之间的各种关联，基于分析结果，提出了一个需求描述前的需求跟踪模型，包括过程模型和数据模型：过程模型描述跟踪过程，数据模型描述原始需求和中间产品。最后应用模型跟踪一个设备租赁系统中费用计算的需求，结果表明利用该模型能够准确跟踪到需求来源，发现需求错误、遗漏和不一致，并消除错误影响，从而改进需求质量，其有效性得到了验证。     

非功能需求的结构化定义以及概念性追踪管理框架

针对需求工程中非功能需求概念非常模糊甚至相互矛盾、非功能需求与其他非功能需求及功能需求之间的关系繁复而难以分析和建模、非功能需求与设计阶段制品之间的追踪关系模糊而不易记录和维护等问题,分析了与非功能需求相关的概念在需求分析阶段和体系结构设计阶段的表现形式,给出了一个结构化的非功能需求定义;规范了不同类型需求之间的各种复杂关系,建立了一个跨越分析和设计阶段的概念性非功能需求追踪管理框架,规范了需求分析和体系结构设计阶段与非功能需求相关的概念和制品之间的关系。提出的结构化定义以及概念性追踪管理框架明确地刻画了非功能需求概念的外延,为简化需求模型以及进一步研制系统化、实用化的非功能需求建模及追踪管理技术奠定了理论基础。     

一种基于领域知识的非功能需求建模辅助方法

随着信息化的普及,人们对软件系统质量要求越来越高,由于体现涉众对软件质量要求的非功能需求具有抽象、主观、不确定等特性,纯粹依赖人工方式对非功能需求建模是一项十分困难的任务.利用领域工程具有的内聚性和稳定性,提出一种基于领域知识的非功能需求建模辅助方法,通过挖掘隐含领域知识,层次化地组织领域知识,能够弥补个人知识的不足,更准确、完整地建模非功能需求.该方法包含两个部分:(1)基于不确定性理论的领域知识获取及分析模块;(2)基于NFR(Non-Functional Requirements)框架的非功能需求辅助建模模块.通过建立非功能属性分解树、设计基于三角模糊数的评价语言值量化机制和传递依赖关系计算方法,实现了对领域知识的准备;建立了非功能属性及非功能需求间依赖关系的形式化定义和推理规则,提出了基于RE-Tools的NFR扩展,实现了对领域知识的应用.案例研究表明,文中方法具有良好的可操作性,能够辅助建模需求关联,减轻需求工程师的工作负荷;同时,交叉实验结果表明,该方法可提升传统NFR框架方法的效率和准确度.     

浅谈软件需求开发与管理

本文主要从软件需求的几个阶段来描述软件需求的实施步骤以及应考虑的问题，从而使人们更加深刻地了解需求的必要性和重要性。     

MOQARE: misuse-oriented quality requirements engineering

This work presents MOQARE (misuse-oriented quality requirements engineering), a method to explore quality requirements. The aim of MOQARE is to support intuitive and systematic identification of quality requirements. It was developed by integrating and adapting concepts from other methods (like Misuse Cases). It provides a general conceptual model of quality requirements, and a checklist-based process for deriving them in a top-down fashion. This derivation starts from business goals and vague quality requirements and delivers detailed requirements. MOQARE applies to requirements on the system to be developed requirements, but also derives requirements on the development process, including administration and maintenance. It considers normal and extreme use. The relationships among these requirements are modeled in a Misuse Tree. MOQARE has shown its merits in several case studies, one of which is presented here.     

User viewpoint modelling: understanding and representing user viewpoints during requirements definition

There has been increasing awareness of the impact of the early stages of systems development on the quality of information systems. A critical early activity is requirements definition, when the requirements for an information system are determined. Traditional requirements capture techniques do not support the collaborative nature of requirements definition or the emergent nature of requirements themselves. This paper focuses on viewpoint development as a means of resolving some of the difficulties of requirements definition. It proposes a user viewpoint model for capturing and representing the viewpoints of users during requirements acquisition. The model can facilitate communication and interaction between analysts and users and help build a shared understanding of requirements. It can be used to structure the requirements acquisition process. The model provides for evaluation of requirements acquisition techniques to guide the selection of appropriate techniques for developing user viewpoint models. The paper reports a multiple-case study of requirements definition efforts that examined user viewpoint development in practice and used the cases to validate empirically the concepts of the user viewpoint model. The implications of the case study findings for requirements definition practice are discussed, and some areas for future research are identified.     

Towards automated requirements prioritization and triage

Time-to-market deadlines and budgetary restrictions require stakeholders to carefully prioritize requirements and determine which ones to implement in a given product release. Unfortunately, existing prioritization techniques do not provide sufficient automation for large projects with hundreds of stakeholders and thousands of potentially conflicting requests and requirements. This paper therefore describes a new approach for automating a significant part of the prioritization process. The proposed method utilizes data-mining and machine learning techniques to prioritize requirements according to stakeholders’ interests, business goals, and cross-cutting concerns such as security or performance requirements. The effectiveness of the approach is illustrated and evaluated through two case studies based on the requirements of the Ice Breaker System, and also on a set of stakeholders’ raw feature requests mined from the discussion forum of an open source product named SugarCRM.     

基于对象的嵌入式实时软件需求模型

The embedded real-time software requirements are analyzed, and an object-oriented software requirements model is proposed. At the same time, an example, employing this requirements model is introduced in practice.     

Obsolete software requirements

ContextCoping with rapid requirements change is crucial for staying competitive in the software business. Frequently changing customer needs and fierce competition are typical drivers of rapid requirements evolution resulting in requirements obsolescence even before project completion.ObjectiveAlthough the obsolete requirements phenomenon and the implications of not addressing them are known, there is a lack of empirical research dedicated to understanding the nature of obsolete software requirements and their role in requirements management.MethodIn this paper, we report results from an empirical investigation with 219 respondents aimed at investigating the phenomenon of obsolete software requirements.ResultsOur results contain, but are not limited to, defining the phenomenon of obsolete software requirements, investigating how they are handled in industry today and their potential impact.ConclusionWe conclude that obsolete software requirements constitute a significant challenge for companies developing software intensive products, in particular in large projects, and that companies rarely have processes for handling obsolete software requirements. Further, our results call for future research in creating automated methods for obsolete software requirements identification and management, methods that could enable efficient obsolete software requirements management in large projects.     

The brave new world of design requirements

Despite its success over the last 30 years, the field of Requirements Engineering (RE) is still experiencing fundamental problems that indicate a need for a change of focus to better ground its research on issues underpinning current practices. We posit that these practices have changed significantly in recent years. To this end we explore changes in software system operational environments, targets, and the process of RE. Our explorations include a field study, as well as two workshops that brought together experts from academia and industry. We recognize that these changes influence the nature of central RE research questions. We identify four new principles that underlie contemporary requirements processes, namely: (1) intertwining of requirements with implementation and organizational contexts, (2) dynamic evolution of requirements, (3) emergence of architectures as a critical stabilizing force, and (4) need to recognize unprecedented levels of design complexity. We recommend a re-focus of RE research based on a review and analysis of these four principles, and identify several theoretical and practical implications that flow from this analysis.     

An experiment on linguistic tool support for consolidation of requirements from multiple sources in market-driven product development

This paper presents an experiment with a linguistic support tool for consolidation of requirements sets. The experiment is designed based on the requirements management process at a large market-driven software development company that develops generic solutions to satisfy many different customers. New requirements and requests for information are continuously issued, which must be analyzed and responded to. The new requirements should first be consolidated with the old to avoid reanalysis of previously elicited requirements and to complement existing requirements with new information. In the presented experiment, a new open-source tool is evaluated in a laboratory setting. The tool uses linguistic engineering techniques to calculate similarities between requirements and presents a ranked list of suggested similar requirements, between which links may be assigned. It is hypothesized that the proposed technique for finding and linking similar requirements makes the consolidation more efficient. The results show that subjects that are given the support provided by the tool are significantly more efficient and more correct in consolidating two requirements sets, than are subjects that do not get the support. The results suggest that the proposed techniques may give valuable support and save time in an industrial requirements consolidation process.     

Agile requirements engineering via paraconsistent reasoning

Innovative companies need an agile approach towards product and service requirements, to rapidly respond to and exploit changing conditions. The agile approach to requirements must nonetheless be systematic, especially with respect to accommodating legal and non-functional requirements. This paper examines how to support lightweight, agile requirements processes which can still be systematically modeled, analyzed and changed. We propose a framework, RE-KOMBINE, which is based on a propositional language for requirements modeling called Techne. We define operations on Techne models which tolerate the presence of inconsistencies. This paraconsistent reasoning is vital for supporting delayed commitment to particular design solutions. We evaluate these operations with an industry case study using two well-known formal analysis tools. Our evaluations show that the proposed framework scales to industry-sized requirements model, while still retaining (via propositional logic) the informality that is so useful during early requirements analysis.