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。通过利益相关者需求导出系统需求与系统功能,在对系统内部结构进行逻辑分析后定义了平台系统架构,实现了系统架构综合,搭建了完备的PHM开发平台MBSE模型。基于MBSE的设计过程使该模型具有结构清晰、集成性高、追溯性强的特点,模型化的设计方法保证了其通用性与可重用性。该模型的建立为PHM开发平台搭建提供了设计流程与解决方案。     

CORAMOD: a checklist-oriented model-based requirements analysis approach

Requirement development activities such as requirements analysis and modelling are well defined in software engineering. A model-based requirement development may result in significant improvements in engineering design. In current product development activities in this domain, not all requirements are consciously identified and modelled. This paper presents the checklist-oriented requirements analysis modelling (CORAMOD) approach. CORAMOD is a methodology for the use of model-based systems engineering for requirements analysis of complex products utilizing checklists, the simplest kind of rational design method. The model-based focuses the requirements analysis process on requirement modelling, whereas the checklist encourages a conscious and systematic approach to identify requirements. We illustrate the utility of CORAMOD artefacts by a comprehensive case study example and modelling with system modelling language (SysML). We suggest that visual accessibility of the SysML views facilitates the full participation of all stakeholders and enables the necessary dialogue and negotiation. The approach promotes tracing derived requirements to the customer need statement and enhances validation by model execution and simulation.     

Synergy between Activity Theory and goal/scenario modeling for requirements elicitation,analysis, and evolution

ContextIt is challenging to develop comprehensive, consistent, analyzable requirements models for evolving requirements. This is particularly critical for certain highly interactive types of socio-technical systems that involve a wide range of stakeholders with disparate backgrounds; system success is often dependent on how well local social constraints are addressed in system design.ObjectiveThis paper describes feasibility research, combining a holistic social system perspective provided by Activity Theory (AT), a psychological paradigm, with existing system development methodologies and tools, specifically goal and scenario modeling.MethodAT is used to understand the relationships between a system, its stakeholders, and the system’s evolving context. The User Requirements Notation (URN) is used to produce rigorous, analyzable specifications combining goal and scenario models. First, an AT language was developed constraining the framework for automation, second consistency heuristics were developed for constructing and analyzing combined AT/URN models, third a combined AT/URN methodology was developed, and consequently applied to a proof-of-concept system.ResultsAn AT language with limited tool support was developed, as was a combined AT/URN methodology. This methodology was applied to an evolving disease management system to demonstrate the feasibility of adapting AT for use in system development with existing methodologies and tools. Bi-directional transformations between the languages allow proposed changes in system design to be propagated to AT models for use in stakeholder discussions regarding system evolution.ConclusionsThe AT framework can be constrained for use in requirements elicitation and combined with URN tools to provide system designs that include social system perspectives. The developed AT/URN methodology can help engineers to track the impact on system design due to requirement changes triggered by changes in the system’s social context. The methodology also allows engineers to assess the impact of proposed system design changes on the social elements of the system context.     

A systematic literature review of stakeholder identification methods in requirements elicitation

This paper presents a systematic review of relevant published studies related to topics in Requirements Engineering, specifically, concerning stakeholder identification methods in requirements elicitation, dated from 1984 to 2011. Addressing four specific research questions, this systematic literature review shows the following evidence gathered from these studies: current status of stakeholder identification in software requirement elicitation, the best practices recommended for its performance, consequences of incorrect identification in requirements quality, and, aspects which need to be improved. Our findings suggest that the analyzed approaches still have serious limitations in terms of covering all aspects of stakeholder identification as an important part of requirements elicitation. However, through correctly identifying and understanding the stakeholders, it is possible to develop high quality software.     

An intelligent assistant for requirements validation

The process of determining user requirements for software systems is often plagued with uncertainty, ambiguity, and inconsistency. Rapid prototyping offers an iterative approach to requirements engineering that can be used to alleviate some of the problems with communication and understanding. Since the systems development process is characterized by changing requirements and assumptions, involving multiple stakeholders with often differing viewpoints, it is beneficial to capture the justifications for the decisions in the development process in a structured manner. Thisdesign rationale captured during requirements engineering can be used in conjunction with the rapid prototyping process to support various stakeholders involved in systems development. CAPS (the Computer Aided Prototyping System) has been built to help software engineers rapidly construct prototypes of proposed software systems. REMAP (Representation and MAintenance of Process knowledge) provides a conceptual model and mechanisms to represent and reason with (design) rationale knowledge. In this paper, we describe how in the context of evolving requirements, the CAPS system augmented with REMAP helps firm up software requirements through iterative negotiations via examination of executable prototypes and reasoning with design rationale knowledge.     

Guest Editors' Introduction: Stakeholders in Requirements Engineering

The growing attention being paid to stakeholders' needs and desires reflects the growing importance of requirements engineering (RE) in software and systems development. This introduction reviews the RE process: identifying the stakeholders in a project, determining who and how important they are, prioritizing the identified stakeholder roles, and selecting representative individuals or groups from the identified and prioritized stakeholder roles with whom the development team can elicit and validate system requirements. The authors then mention each article in the issue in the context of today's latest thinking on RE. This article introduces a special issue on stakeholders in requirements engineering.     

Role of situational method engineering to improve visual information systems in agile distributed environment

Software product prone to continuous evolution due to increase in the use of technology. Therefore, more stakeholders are involved in software evolution increases the cost and complexity. This required optimization of resources and cost to handle evolution with Global Software Development (GSD) to utilize time zones efficiently. The significance challenge of GSD reports: time zone difference, geographical location, communication delays, knowledge sharing, control among stakeholders and development team. Because of these challenges, the requirements for development in GSD environment are also challenge as compared to on site development. Different requirement engineering methods have been used to improve the requirements analysis to deal with ambiguities and inconsistency in large set of requirements. The customization and tailoring of requirements according to changing project’s situations required to improve project development with reusing existing agile methods during requirement engineering phase. Moreover, complex information systems where heterogeneity is inevitable that implies the involvement of divergent stakeholders and necessitate a comprehensive framework to capture multidimensional viewpoints and fulfill aforementioned issues. Therefore, a situational multi-dimensional agile requirement engineering method has been proposed to support team and stakeholders’ viewpoints. The schema of the proposed method is based on challenges recognized by performing Literature Review. Then proposed method has been evaluated via experimental approach and statistical analysis conducted to validated reliability of data collected. This result is significant approved both practically and statistically that the proposed approach ease to use, implement, trained and increased productivity and performance. Hence, the experimental study for the evaluation of the proposed approach results concluded that, proposed approach is the important multimedia tool for supporting organization and distributed development team for information sharing, collaboration, product development.

     

典型机电系统PHM评价指标分析

PHM评价指标是装备健康管理系统设计输入与目标要求,也是对PHM系统进行验收核查的评价依据;目前国内航空主机所、科研院所与高校开展了大量的PHM技术研究和工程设计应用工作,但由于缺乏PHM系统指标体系的建立,导致研制方在PHM系统设计阶段难以明确功能性能要求,验证方在定型阶段缺乏统一的评价参考标准,使PHM系统的工程化进程缓慢;文章以典型机电系统为研究对象,通过剖析国外先进的PHM技术标准与规范文件,结合装备典型机电系统PHM系统的能力需求,从机电系统PHM的监测及诊断指标、预测指标、决策及评价指标三个维度分析和梳理PHM评价指标,建立了适用于装备设计与验证需求的机电系统PHM评价指标体系,解决了装备PHM系统设计中缺乏设计依据与验证评价指标的问题.     

A computational argumentation methodology for capturing and analyzing design rationale arising from multiple perspectives

Contemporary development methodologies provide for the traceability of design decisions to functional requirements. However, they fail to adequately provide this type of traceability for non-functional requirements. This paper describes a methodology for the computational evaluation of the impact of design decisions on the non-functional requirements of the various stakeholders involved in the development of a system. A design dialog process based upon a design argumentation model is described. The dialog process provides for the capture of design rationale and for their management. Fuzzy inference is used to identify conflicts, to simply arguments, and to measure the favorability of an argument.     

A questionnaire-based survey methodology for systematically validating goal-oriented models

Goal models represent interests, intentions, and strategies of different stakeholders. Reasoning about the goals of a system unavoidably involves the transformation of unclear stakeholder requirements into goal-oriented models. The ability to validate goal models would support the early detection of unclear requirements, ambiguities, and conflicts. In this paper, we propose a novel validation approach based on the Goal-oriented Requirement Language (GRL) to check the correctness of GRL goal models through statistical analyses of data collected from generated questionnaires. System stakeholders (e.g., customers, shareholders, and managers) may have different objectives, interests, and priorities. Stakeholder conflicts arise when the needs of some group of stakeholder compromise the expectations of some other group(s) of stakeholders. Our proposed approach allows for early detection of potential conflicts amongst intervening stakeholders of the system. In order to illustrate and demonstrate the feasibility of the approach, we apply it to a case study of a GRL model describing the fostering of the relationship between the university and its alumni. The approach brings unique benefits over the state of the art and is complementary to existing validation approaches.     

涉众为中心的敏捷需求建模

提出一种将涉众为中心和敏捷方法有机结合的敏捷需求建模方法。所有软件系统需求获取以涉众为中心,基于涉众扩展特征建立涉众Power/Interest分布图来确定涉众优先级,并用优先级处理不同涉众之间的需求冲突,根据涉众为中心的敏捷需求方法,提出敏捷需求实践方法,融合敏捷方法的短周期、演化、增量、迭代、重构、反馈机制,使软件系统需求建模过程更加完备、精确、高效、快捷,用双变迁Petri网DTPN为该方法建立形式化敏捷需求模型,为软件系统需求建模提出了一种新的方法。     

Managing conflicts in goal-driven requirements engineering

A wide range of inconsistencies can arise during requirements engineering as goals and requirements are elicited from multiple stakeholders. Resolving such inconsistencies sooner or later in the process is a necessary condition for successful development of the software implementing those requirements. The paper first reviews the main types of inconsistency that can arise during requirements elaboration, defining them in an integrated framework and exploring their interrelationships. It then concentrates on the specific case of conflicting formulations of goals and requirements among different stakeholder viewpoints or within a single viewpoint. A frequent, weaker form of conflict called divergence is introduced and studied in depth. Formal techniques and heuristics are proposed for detecting conflicts and divergences from specifications of goals/requirements and of domain properties. Various techniques are then discussed for resolving conflicts and divergences systematically by the introduction of new goals or by transforming the specifications of goals/objects toward conflict-free versions. Numerous examples are given throughout the paper to illustrate the practical relevance of the concepts and techniques presented. The latter are discussed in the framework of the KAOS methodology for goal-driven requirements engineering     

Representing and reasoning about preferences in requirements engineering

The priorities that stakeholders associate with requirements may vary from stakeholder to stakeholder and from one situation to the next. Differing priorities, in turn, imply different design decisions for the system to be. While elicitation of requirement priorities is a well-studied activity, modeling and reasoning with prioritization has not enjoyed equal attention. In this paper, we address this problem by extending a state-of-the-art goal modeling notation to support the representation of preference (??nice-to-have??) requirements. In our extension, preference goals are distinguished from mandatory ones. Then, quantitative prioritizations of the former are constructed and used as criteria for evaluating alternative ways to achieve the latter. To generate solutions, an existing preference-based planner is utilized to efficiently search for alternatives that best satisfy a given set of mandatory and preferred requirements. With such a planning tool, analysts can acquire a better understanding of the impact of high-level stakeholder preferences on low-level design decisions.     

Workshop videos for requirements communication

Shared understanding of requirements between stakeholders and the development team is a critical success factor for requirements engineering. Workshops are an effective means for achieving such shared understanding. Stakeholders and team representatives can meet and discuss what a planned software system should be and how it should support achieving stakeholder goals. However, some important intended recipients of the requirements are often not present in such workshops: the developers. Thus, they cannot benefit from the in-depth understanding of the requirements and of the rationales for these requirements that develops during the workshops. The simple handover of a requirements specification hardly compensates the rich requirements understanding that is needed for the development of an acceptable system. To compensate the lack of presence in a requirements workshop, we propose to record that requirements workshop on video. If workshop participants agree to be recorded, a video is relatively simple to create and can capture much more aspects about requirements and rationales than a specification document. This paper presents the workshop video technique and a phenomenological evaluation of its use for requirements communication from the perspective of software developers. The results show how the technique was appreciated by observers of the video, present positive and negative feedbacks from the observers, and lead to recommendations for implementing the technique in practice.     

Stakeholder Risk Assessment: An Outcome-Based Approach

Managing software projects can often degrade into fighting fires lit by the embers of unrecognized and unmanaged risks. Stakeholders are a recognized source of significant software project risk, but few researchers have focused on providing a practical method for identifying specific project stakeholders. Furthermore, no methods provide guidance in identifying and managing project risks arising from those stakeholders. We developed the outcome-based stakeholder risk assessment model to provide this practical guidance. OBSRAM offers the project team a step-by-step approach to identifying stakeholders during requirements engineering, identifying stakeholder influences on the project, identifying the project's impact on stakeholders, and assessing the risks that their potential negative responses pose. We illustrate OBSRAM using a case study of a simulated airline-crew-scheduling system project that aims to reduce aircraft ground turnaround time to 30 minutes or less     

An Industrial Case Study on Distributed Prioritisation in Market-Driven Requirements Engineering for Packaged Software

When developing packaged software, which is sold ‘off-the-shelf’ on a worldwide marketplace, it is essential to collect needs and opportunities from different market segments and use this information in the prioritisation of requirements for the next software release. This paper presents an industrial case study where a distributed prioritisation process is proposed, observed and evaluated. The stakeholders in the requirements prioritisation process include marketing offices distributed around the world. A major objective of the distributed prioritisation is to gather and highlight the differences and similarities in the requirement priorities of the different market segments. The evaluation through questionnaires shows that the stakeholders found the process useful. The paper also presents novel approaches to visualise the priority distribution among stakeholders, together with measures on disagreement and satisfaction. Product management found the proposed charts valuable as decision support when selecting requirements for the next release, as they revealed unforeseen differences among stakeholder priorities. Conclusions on stakeholder tactics are provided and issues of further research are identified, including ways of addressing identified challenges.     

Using viewpoints to define domain requirements

Although requirements reuse has many potential benefits, a lack of accepted methodology for sorting through a domain's myriad requirement specifications makes the task daunting. The authors' VODRD (Viewpoint Oriented Domain Requirements Definition) method relies on stakeholder viewpoints to organize user requirements. They describe their method and its application in a mission planning system for the European Space Agency     

Building Large,Complex, Distributed Safety-Critical Operating Systems

Safety-critical systems typically operate in unpredictable environments. Requirements for safety and reliability are in conflict with those for real-time responsiveness. Due to unpredictable environmental needs there is no static trade-off between measures to accommodate the conflicting objectives. Instead every feature or operating system service has to be adaptive. Finally, for any design problem, there cannot be any closed-form (formal) approach taking care at the same time of (external) time constraints or deadlines, and synchronization requirements in distributed design. The reason is that these two aspects are causally independent. - In this situation we worked out a heuristic experimental, performance-driven and performance-based methodology that allows in an educated way to start with a coarse system model, with accurate logical expectations regarding its behavior. Through experiments these expectations are validated. If they are found to successfully stand the tests extended expectations and model features are generated for refining the previous design as well as its performance criteria. The refinement is done in such a way that the previous experimental configurations are extreme model cases or data profiles which both logically and experimentally are to reproduce the behavior of the previous modeling step. Thus the novel performance aspects or tendencies could then unambiguously be attributed to the influences of the refined model features. We termed this methodology Incremental Experimentation. As a general methodology it relies on a principle of comparative performance studies rather than on realistic data for narrow application ranges. The paper describes how we applied a 5-step design and refinement procedure for developing, analyzing, and evaluating our distributed operating system MELODY that exhibits novel services for supporting real-time and safety-critical applications in unpredictable environments. Experimental set-ups and theme-related findings are discussed in particular.