A requirements engineering process for control engineering software

This paper presents a novel approach for the specification of control engineering software. The proposal is based on software engineering techniques which have improved the performance and quality of software processes. Some of the best practices for the building of software products are included. An example of the proposal is given for the requirements specification of the 1992 ACC robust control benchmark.     

A practitioner’s guide to light weight software process assessment and improvement planning

Software process improvement (SPI) is challenging, particularly for small and medium sized enterprises. Most existing SPI frameworks are either too expensive to deploy, or do not take an organizations’ specific needs into consideration. There is a need for light weight SPI frameworks that enable practitioners to base improvement efforts on the issues that are the most critical for the specific organization.

This paper presents a step-by-step guide to process assessment and improvement planning using improvement framework utilizing light weight assessment and improvement planning (iFLAP), aimed at practitioners undertaking SPI initiatives. In addition to the guide itself the industrial application of iFLAP is shown through two industrial cases. iFLAP is a packaged improvement framework, containing both assessment and improvement planning capabilities, explicitly developed to be light weight in nature. Assessment is performed by eliciting improvements issues based on the organization’s experience and knowledge. The findings are validated through triangulation utilizing multiple data sources. iFLAP actively involves practitioners in prioritizing improvement issues and identifying dependencies between them in order to package improvements, and thus establish a, for the organization, realistic improvement plan. The two cases of iFLAP application in industry are presented together with lessons learned in order to exemplify actual use of the framework as well as challenges encountered.     

软件项目需求波动风险分析及对策

从需求波动风险的定义出发,总结了需求波动形成的原因和对软件项目的影响,列举了一些代表性的风险分析和评估方法。最后提出了基于面向对象方法的系统需求工程的分析设计思路。     

An operational model for structuring the requirements generation process

Product quality is directly related to how well that product meets the customers needs and intents. Therefore, the ability to capture customer requirements correctly and succinctly is paramount. Unfortunately, within most software development frameworks requirements elicitation, recording and evaluation are some of the more ill-defined and least structured activities. To help address such inadequacies, we propose a requirements generation model (RGM) that (a) decomposes the conventional requirements analysis phase into sub-phases which focus and refine requirement generation activities, (b) bounds and structures those activities to promote a more effective generation process, and (c) implements a monitoring methodology to assist in detecting deviations from well-defined procedures intended to support the generation of requirements that meet the customers intent. The RGM incorporates lessons learned from a preliminary study that concentrated on identifying where and how miscommunication and requirements omission occur. An industry study (also reported in this paper) attests to the effectiveness of the RGM. The results of that study indicate that the RGM helps (a) reduce the late discovery of requirements, (b) reduce the slippage in milestone completion dates, and (c) increase customer and management satisfaction levels.     

Managing the requirements engineering process

Process management is a crucial issue in developing information or computer systems. Theories of software development process management suggest that the process should be supported and managed based on what the process really is. However, our learning from an action research study reveals that the requirements engineering (RE) process differs significantly from that which the current literature tends to describe. The process is not a systematic, smooth and incremental evolution of the requirements model, but involves occasional simplification and restructuring of the requirements model. This revised understanding of the RE process suggests a new challenge to both the academic and industrial communities, demanding new process management approaches. In this paper, we present our understanding of the RE process and its implications for process management.     

Reliability factors in business software: volatility, requirements and end-users

Abstract. Many business‐oriented software applications are subject to frequent changes in requirements. This paper shows that, ceteris paribus, increases in the volatility of system requirements decrease the reliability of software. Further, systems that exhibit high volatility during the development phase are likely to have lower reliability during their operational phase. In addition to the typically higher volatility of requirements, end‐users who specify the requirements of business‐oriented systems are usually less technically oriented than people who specify the requirements of compilers, radar tracking systems or medical equipment. Hence, the characteristics of software reliability problems for business‐oriented systems are likely to differ significantly from those of more technically oriented systems.     

A methodology for the classification of quality of requirements using machine learning techniques

ContextOne of the most important factors in the development of a software project is the quality of their requirements. Erroneous requirements, if not detected early, may cause many serious problems, such as substantial additional costs, failure to meet the expected objectives and delays in delivery dates. For these reasons, great effort must be devoted in requirements engineering to ensure that the project’s requirements results are of high quality. One of the aims of this discipline is the automatic processing of requirements for assessing their quality; this aim, however, results in a complex task because the quality of requirements depends mostly on the interpretation of experts and the necessities and demands of the project at hand.ObjectiveThe objective of this paper is to assess the quality of requirements automatically, emulating the assessment that a quality expert of a project would assess.MethodThe proposed methodology is based on the idea of learning based on standard metrics that represent the characteristics that an expert takes into consideration when deciding on the good or bad quality of requirements. Using machine learning techniques, a classifier is trained with requirements earlier classified by the expert, which then is used for classifying newly provided requirements.ResultsWe present two approaches to represent the methodology with two situations of the problem in function of the requirement corpus learning balancing, obtaining different results in the accuracy and the efficiency in order to evaluate both representations. The paper demonstrates the reliability of the methodology by presenting a case study with requirements provided by the Requirements Working Group of the INCOSE organization.ConclusionsA methodology that evaluates the quality of requirements written in natural language is presented in order to emulate the quality that the expert would provide for new requirements, with 86.1 of average in the accuracy.     

Evaluation of a game to teach requirements collection and analysis in software engineering at tertiary education level

A highly important part of software engineering education is requirements collection and analysis which is one of the initial stages of the Database Application Lifecycle and arguably the most important stage of the Software Development Lifecycle. No other conceptual work is as difficult to rectify at a later stage or as damaging to the overall system if performed incorrectly. As software engineering is a field with a reputation for producing graduates who are inappropriately prepared for applying their skills in real life software engineering scenarios, it suggests that traditional educational techniques such as role-play, live-through case studies and paper-based case studies are insufficient preparation and that other approaches are required. To attempt to combat this problem we have developed a games-based learning application to teach requirements collection and analysis at tertiary education level as games-based learning is seen as a highly motivating, engaging form of media and is a rapidly expanding field. This paper will describe the evaluation of the requirements collection and analysis game particularly from a pedagogical perspective. The game will be compared to traditional methods of software engineering education using a pre-test/post-test, control group/experimental group design to assess if the game can act as a suitable supplement to traditional techniques and assess if it can potentially overcome shortcomings. The game will be evaluated in five separate experiments at tertiary education level.     

Relationship analysis in requirements engineering

This research addresses a major shortcoming in todays requirements analysis techniques—the lack of a rigorous and comprehensive process to explicitly capture the relationship structure of the problem domain. Whereas other analysis techniques lightly address the relationship discovery process, relationship analysis (RA) is a systematic, domain-independent analysis technique focusing exclusively on a domains relationship structure. This paper describes RAs taxonomy of relationship types and corresponding brainstorming questions for eliciting the relationship structure from a domain expert. A preliminary case study analysis of online bookstores using RA as well as a formal experiment have both confirmed RAs effectiveness in helping the analyst produce significantly higher quality requirements. RA should become an invaluable tool for analysts, irrespective of the software engineering approach taken during systems analysis.     

A systematic literature review of software requirements prioritization research

ContextDuring requirements engineering, prioritization is performed to grade or rank requirements in their order of importance and subsequent implementation releases. It is a major step taken in making crucial decisions so as to increase the economic value of a system.ObjectiveThe purpose of this study is to identify and analyze existing prioritization techniques in the context of the formulated research questions.MethodSearch terms with relevant keywords were used to identify primary studies that relate requirements prioritization classified under journal articles, conference papers, workshops, symposiums, book chapters and IEEE bulletins.Results73 Primary studies were selected from the search processes. Out of these studies; 13 were journal articles, 35 were conference papers and 8 were workshop papers. Furthermore, contributions from symposiums as well as IEEE bulletins were 2 each while the total number of book chapters amounted to 13.ConclusionPrioritization has been significantly discussed in the requirements engineering domain. However, it was generally discovered that, existing prioritization techniques suffer from a number of limitations which includes: lack of scalability, methods of dealing with rank updates during requirements evolution, coordination among stakeholders and requirements dependency issues. Also, the applicability of existing techniques in complex and real setting has not been reported yet.     

Deriving static and dynamic concepts from software requirements using sophisticated tagging

Natural language requirements specifications form the basis for the subsequent phase of the information system development process, namely the development of conceptual schemata. Both, the textual as well as the conceptual representations are not really appropriate for being thoroughly captured and validated by the ‘requirement holders’, i.e. the end users. Therefore, in our approach the textual specifications are firstly linguistically analyzed and translated into a so-called conceptual predesign schema. That schema is formulated using an interlingua which is based on a lean semantic model, thus allowing users to participate more efficiently in the design and validation process. After validation, the predesign schema is mapped to a conceptual representation (e.g. UML). The sequence of these translation and transformation steps is described by the “NIBA workflow”. This paper focuses on the information supporting a step by step mapping of natural language requirements specifications to a conceptual model, and on how that information is gained. On particular, we present a four-level interpretation of tagging-output.     

A measurement framework for assessing the maturity of requirements engineering process

Because requirements engineering (RE) problems are widely acknowledged as having a major impact on the effectiveness of the software development process, Sommerville et al. have developed a requirements maturity model. However, research has shown that the measurement process within Sommerville’s model is ambiguous, and implementation of his requirements maturity model leads to confusion. Hence, the objective of our research is to propose a new RE maturity measurement framework (REMMF) based on Sommerville’s model and to provide initial validation of REMMF. The main purpose of proposing REMMF is to allow us to more effectively measure the maturity of the RE processes being used within organisations and to assist practitioners in measuring the maturity of their RE processes. In order to evaluate REMMF, two organisations implemented the measurement framework within their IT divisions, provided us with an assessment of their requirements process and gave feedback on the REMMF measurement process. The results show that our measurement framework is clear, easy to use and provides an entry point through which the practitioners can effectively judge the strengths and weakness of their RE processes. When an organisation knows where it is, it can more effectively plan for improvement.

Understanding replication of experiments in software engineering: A classification

ContextReplication plays an important role in experimental disciplines. There are still many uncertainties about how to proceed with replications of SE experiments. Should replicators reuse the baseline experiment materials? How much liaison should there be among the original and replicating experimenters, if any? What elements of the experimental configuration can be changed for the experiment to be considered a replication rather than a new experiment?ObjectiveTo improve our understanding of SE experiment replication, in this work we propose a classification which is intend to provide experimenters with guidance about what types of replication they can perform.MethodThe research approach followed is structured according to the following activities: (1) a literature review of experiment replication in SE and in other disciplines, (2) identification of typical elements that compose an experimental configuration, (3) identification of different replications purposes and (4) development of a classification of experiment replications for SE.ResultsWe propose a classification of replications which provides experimenters in SE with guidance about what changes can they make in a replication and, based on these, what verification purposes such a replication can serve. The proposed classification helped to accommodate opposing views within a broader framework, it is capable of accounting for less similar replications to more similar ones regarding the baseline experiment.ConclusionThe aim of replication is to verify results, but different types of replication serve special verification purposes and afford different degrees of change. Each replication type helps to discover particular experimental conditions that might influence the results. The proposed classification can be used to identify changes in a replication and, based on these, understand the level of verification.     

An approach to analyzing the software process change impact using process slicing and simulation

When a software process is changed, a project manager needs to perform two types of change impact analysis activities: one for identifying the affected elements of a software process which is affected by the change and the other for analyzing the quantitative impact of the change on the project performance. We propose an approach to obtain the affected elements of a software process using process slicing and developing a simulation model based on the affected elements to quantitatively analyzing the change using simulation. We suggest process slicing to obtain the elements affected by the change. Process slicing identifies the affected elements of a software process using a process dependency model. The process dependency model contains activity control dependencies, artifact information dependencies, and role replacement dependencies. We also suggest transformation algorithms to automatically derive the simulation model from the process model containing the affected elements. The quantitative analysis can be performed by simulating the simulation model. In addition, we provide the tool to support our approach. We perform a case study to validate the usefulness of our approach. The result of the case study shows that our approach can reduce the effort to identify the elements affected by changes and examine alternatives for the project.     

Software product line scoping and requirements engineering in a small and medium-sized enterprise: An industrial case study

Software product line (SPL) engineering has been applied in several domains, especially in large-scale software development. Given the benefits experienced and reported, SPL engineering has increasingly garnered interest from small to medium-sized companies. It is possible to find a wide range of studies reporting on the challenges of running a SPL project in large companies. However, very little reports exist that consider the situation for small to medium-sized enterprises and these studies try develop universal truths for SPL without lessons learned from empirical evidence need to be contextualized. This study is a step towards bridging this gap in contextual evidence by characterizing the weaknesses discovered in the scoping (SC) and requirements (RE) disciplines of SPL. Moreover, in this study we conducted a case study in a small to medium sized enterprises (SMEs) to justify the use of agile methods when introducing the SPL SC and RE disciplines through the characterization of their bottlenecks. The results of the characterization indicated that ineffective communication and collaboration, long iteration cycles, and the absence of adaptability and flexibility can increase the effort and reduce motivation during project development. These issues can be mitigated by agile methods.     

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 on the industrial use of software process simulation

ContextSoftware process simulation modelling (SPSM) captures the dynamic behaviour and uncertainty in the software process. Existing literature has conflicting claims about its practical usefulness: SPSM is useful and has an industrial impact; SPSM is useful and has no industrial impact yet; SPSM is not useful and has little potential for industry.ObjectiveTo assess the conflicting standpoints on the usefulness of SPSM.MethodA systematic literature review was performed to identify, assess and aggregate empirical evidence on the usefulness of SPSM.ResultsIn the primary studies, to date, the persistent trend is that of proof-of-concept applications of software process simulation for various purposes (e.g. estimation, training, process improvement, etc.). They score poorly on the stated quality criteria. Also only a few studies report some initial evaluation of the simulation models for the intended purposes.ConclusionThere is a lack of conclusive evidence to substantiate the claimed usefulness of SPSM for any of the intended purposes. A few studies that report the cost of applying simulation do not support the claim that it is an inexpensive method. Furthermore, there is a paramount need for improvement in conducting and reporting simulation studies with an emphasis on evaluation against the intended purpose.     

User participation in the requirements engineering process: An empirical study

In the development of information systems, user participation in the requirements engineering (RE) process is hypothesised to be necessary for RE success. In this paper we develop a theoretical model which predicts that the interaction between user participation in the RE process and uncertainty has an impact on RE success. This theory is empirically tested using survey data. We develop instruments to measure user participation and uncertainty. An existing instrument for measuring RE success was used. This instrument covers two dimensions of RE success: (a) the quality of RE service, and (b) the quality of RE products. The results, indicate that as uncertainty increases, greater user participation alleviates the negative influence of uncertainty on the quality of RE service, and that as uncertainty decreases, the beneficial effects on the quality of RE service of increasing user participation diminish. Furthermore, we did not find that the interaction between user participation and uncertainty had an impact on the quality of RE products. Based on these results, we make recommendations for managing user participation in the RE process, and provide directions for future research.This work has been supported, in part, by the IT Macroscope Project and NSERC Canada.     

Integrating probabilistic design and rare‐event simulation into the requirements engineering process for high‐reliability systems

Early in a program, engineers must determine requirements for system reliability and availability. We suggest that existing techniques gathered from diverse fields can be incorporated within the framework of systems engineering methodology to accomplish this. Specifically, adopting probabilistic (Monte Carlo) design techniques allows the designer to incorporate uncertainty explicitly into the design process and to improve the designer's understanding of the root causes of failures and how often these might realistically occur. In high‐reliability systems in which failure occurs infrequently, rare‐event simulation techniques can reduce the computational burden of achieving this understanding. This paper provides an introductory survey of the literature on systems engineering, requirements engineering, Monte Carlo simulation, probabilistic design, and rare‐event simulation with the aim of assessing the degree to which these have been integrated in systems design for reliability. This leads naturally to a proposed framework for the fusion of these techniques.     

Ontology of systems and software engineering

Systems and software engineering have evolved in the last years in a process of consolidation of their specificities as engineering disciplines. This has resulted in research and inquiry on ontological and epistemological issues related to them. Due to the supporting nature of systems and software engineering with regards to other engineering disciplines, these aspects are also relevant to researchers and practitioners in other engineering domains. The contents of this issue provide a selection of research aimed at consolidating ontology of systems and software engineering as a useful and consistent body of knowledge.