Family-oriented requirements engineering

Abstract Modern software products shall be developed within a short time and at the same time they should be of a high quality. Software engineering is able to fulfill these requirements by prefabricating components. Within a domain, planned and comprehensive reuse of components is supported by the concept of system family development. A system family is based on a reference architecture made of assets, which are common to all family members and assets, which are variable. Commonalities and variabilities have to be considered in all phases of the system family development and they have to be elaborated correctly. Mistakes made in the requirements engineering phase, as the beginning of a development, will cause the most damage to the overall development. The analysis of the requirements engineering phase of system family development in this paper shows, that most of the current scientific solutions in this field are based on feature modeling, although it is inconsistent and cannot be automatically processed. The proposed solution of this paper – Family-Oriented Requirements Engineering (FORE) – extends feature modeling and integrates it into a new data model, capable of holding all the information acquired within the requirements engineering phase. Dependencies within feature models and between features and further model elements can be modeled with the new FORE Feature Constraint Language (FCL). FCL offers 30 predefined dependencies for verifiable system family models. Extended feature models of FORE allow the automated verification of a subset of features. Thus, only valid family members can be derived of the system family. The development of a system family model as well as the derivation of family members are supported by the FORE development process. The FORE-process integrates current processes and the extended feature modeling of FORE into a requirements engineering process for system families. The proposed solution was prototypically realized by implementing the FORE-Data Model as XML-Schema. The usage of the prototype is aimed at the FORE-Development Process. FORE was tested within a University project as well as in several student works with industry partners. The results of this paper have shown the applicability of FORE, improved its process and data model and revealed its limits.Heutige Softwareprodukte sollen in kurzer Zeit bei gleichzeitig hoher Qualität entwickelt werden, wobei die Software-Technik dieser Forderung durch die Vorfertigung einzelner Komponenten gerecht wird. Die geplante und umfassende Wiederverwendung von Komponenten innerhalb einer Anwendungsdomäne wird durch das Konzept der Systemfamilienentwicklung unterstützt. Eine Systemfamilie basiert auf einer Referenzarchitektur, die aus Anteilen besteht, die allen Familienmitgliedern gemein sind und Anteilen, die optional sind. In allen Phasen der Systemfamilienentwicklung müssen gemeinsame und optionale Anteile berücksichtigt und korrekt verarbeitet werden, wobei Fehler in der Requirements-Engineering-Phase, dem Beginn der Entwicklung, den größten wirtschaftlichen Schaden nach sich ziehen. In dieser Arbeit zeigt die Analyse der Requirements-Engineering-Phase der Systemfamilienentwicklung, dass die Systemfamilienmodelle der meisten, existierenden Ansätze auf der Merkmalmodellierung basieren, die jedoch inkonsistent und nicht automatisiert verarbeitbar ist. Der hier beschriebene Lösungsansatz ? Family-Oriented Requirements Engineering (FORE) ? erweitert Merkmalmodelle und integriert sie in ein neues Datenmodell, das alle im Verlauf der Requirements-Engineering-Phase erarbeiteten Informationen enthält. Zur Modellierung aller Abhängigkeiten innerhalb von Merkmalmodellen und von Merkmalen zu weiteren Modellelementen bietet FORE die neue Feature Constraint Language (FCL) mit 30 vordefinierten Beziehungen an, wodurch Systemfamilienmodelle überprüfbar sind. Durch die kundenspezifische Auswahl von Merkmalen wird ein Familienmitglied basierend auf der Systemfamilie abgeleitet. Die erweiterten Merkmalmodelle von FORE ermöglichen die automatisierte Überprüfung einer Merkmalauswahl, sodass nur gültige Familienmitglieder abgeleitet werden können. Sowohl die Entwicklung eines Systemfamilienmodells als auch die Ableitung von Familienmitgliedern werden durch den FORE-Entwicklungsprozess unterstützt, der existierende Ansätze und die erweiterte Merkmalmodellierung in einem Requirements-Engineering-Prozess für Systemfamilien integriert. Anhand eines Prototyps wird die Realisierbarkeit des Lösungsansatzes gezeigt, indem das FORE-Datenmodell in eine XML-Struktur umgesetzt und die Benutzung des Prototyps dem FORE-Entwicklungsprozess folgt. FORE wurde im Rahmen eines universitären Projektes, wie auch durch diverse studentische Arbeiten mit Industriepartnern überprüft. Die Ergebnisse dieser Arbeiten haben die Praxistauglichkeit von FORE gezeigt, den Prozess und das Datenmodell verbessert und dessen Grenzen aufgezeigt

A Survey on Design Pattern Recovery Techniques

The evaluation of design pattern recovery techniques and tools is significant as numbers of emergent techniques are presented and used in the past to recover patterns from source code of legacy applications. The problem of very diverse precision and recall values extracted by different pattern recovery techniques and tools on the same examined applications is not investigated thoroughly. It is very desirable to compare features of existing techniques as abundance of techniques supplemented with different tools has been presented in the last decade. We believe that new innovations for this discipline can be based on the empirical evaluation of existing techniques. The selected techniques cover the whole spectrum of state of the art research in design pattern recovery. The major contribution of this paper is a comprehensive discussion on state of the art in design pattern recovery research in the last decade followed by a proposed framework for classification and evaluation of existing design pattern recovery techniques. Finally we listed our observations as lessons learned which hamper design pattern recovery research and these observations can be used for future research directions and guidelines for this discipline

An analysis of the generative user interface pattern structure

Current business information systems extensively rely on graphical user interfaces (GUIs). These sub-systems enable the interaction between the end user and application kernel services that are essential for the business process instances. Due to dynamic and rapid changes of both business processes and their required services, a strong need for the quick adaptation of GUIs to the occurring changes arose. As both efficiency and usability are essential for the GUI adaptation, model-based development processes that involve patterns and their instantiation for specific GUI contexts have been suggested by ongoing research. Being based on human computer interaction patterns, the new kind of pattern needs to be formalized in order to enable the automated processing of configurable instances by generator tools. However, current research is still at the edge to express the concepts for such generative user interface patterns. Crucial factors and impacts of those patterns have not been described sufficiently yet so that a standardized format for the expression of variability is still missing. With our work, we briefly review the current state on modeling user interface patterns and their requirement aspects. The ultimate objective of this paper is the development of an analysis model that is able to express both the structure and variability concerns of user interface patterns in detail. To evaluate and illustrate the analysis model concepts, selected user interface pattern instances are modeled via object models. As result, a detailed description of generative user interface patterns is achieved, which can be applied as a basis for the verification of recent approaches of model- and pattern-based GUI development or even the synthesis of a dedicated user interface pattern language

Fuzzy based evaluation of software quality using quality models and goal models

Software quality requirements are essential part for the success of software development. Defined and guaranteed quality in software development requires identifying, refining, and predicting quality properties by appropriate means. Goal models of goal oriented requirements engineering (GORE) and quality models are useful for modelling of functional goals as well as for quality goals. Once the goal models are obtained representing the functional requirements and integrated quality goals, there is need to evaluate each functional requirement arising from functional goals and quality requirement arising from quality goals. The process consist of two main parts. In first part, the goal models are used to evaluate functional goals. The leaf level goals are used to establish the evaluation criteria. Stakeholders are also involved to contribute their opinions about the importance of each goal (functional and/or quality goal). Stakeholder opinions are then converted into quantifiable numbers using triangle fuzzy numbers (TFN). After applying the defuzzification process on TFN, the scores (weights) are obtained for each goal. In second part specific quality goals are identified, refined/tailored based on existing quality models and their evaluation is performed similarly using TFN and by applying defuzzification process. The two step process helps to evaluate each goal based on stakeholder opinions and to evaluate the impact of quality requirements. It also helps to evaluate the relationships among functional goals and quality goals. The process is described and applied on ’cyclecomputer’ case study

Alternatives selection using GORE based on fuzzy numbers and TOPSIS

Context and Motivation: The notion of goal and goal models is ideal for the alternative systems. Goal models provide us different alternatives during goal oriented requirements engineering. Question/Problem: Once we find different alternatives, we need to evaluate these alternatives to select the best one. Ideas: The selection process consists of two main parts. In first part of the selection process among alternatives, we will use techniques in which we establish some evaluation criteria. The evaluation criteria are based on leaf level goals. Stakeholders are involved to contribute their opinions about the evaluation criteria. The input provided by various stakeholders is then converted into quantifiable numbers using fuzzy triangle numbers. After applying the defuzzification process on fuzzy triangle numbers we get scores (weights) for each criteria. In second part, these scores are used in the selection process to select the best alternative. Contribution: The two steps selection process helps us to select the best alternative among many alternatives. We have described the process and applied it to “cyclecomputer” selection case study

Goal model integration for tailoring product line development processes

Many companies rely on the promised benefits of product lines, targeting systems between fully custom made software and mass products. Such customized mass products account for a large number of applications automatically derived from a product line. This results in the special importance of product lines for companies with a large part of their product portfolio based on their product line. The success of product line development efforts is highly dependent on tailoring the development process. This paper presents an integrative model of influence factors to tailor product line development processes according to different project needs, organizational goals, individual goals of the developers or constraints of the environment. This model integrates goal models, SPEM models and requirements to tailor development processes

Modeling knowledge bases for automated decision making systems - a literature review

Developing automated decision making systems means dealing with knowledge in every possible manner. One of the most important points of developing artificial intelligent systems is developing a precise knowledge base with integrating self-learning mechanisms. Moreover using knowledge in expert systems or decision support systems it is necessary to document knowledge and make it visible for managing it. Main goal of this work is finding a suitable solution for modeling knowledge bases in automated decision making systems concerning both illustrating specific knowledge and learning mechanisms. There are a lot of different terms describing this kind of research, such as knowledge modeling, knowledge engineering or ontology engineering. For that reason this paper provides a comparison of the technical terms in this domain by illustrating similarities, specifics and how they are used in literature

A real-time capable dynamic partial reconfiguration system for an applicationspecific soft-core processor

Modern FPGAs (Field Programmable Gate Arrays) are becoming increasingly important when it comes to embedded system development. Within these FPGAs, soft-core processors are often used to solve a wide range of different tasks. Soft-core processors are a cost-effective and time-efficient way to realize embedded systems. When using the full potential of FPGAs, it is possible to dynamically reconfigure parts of them during run time without the need to stop the device. This feature is called dynamic partial reconfiguration (DPR). If the DPR approach is to be applied in a real-time application-specific soft-core processor, an architecture must be created that ensures strict compliance with the real-time constraint at all times. In this paper, a novel method that addresses this problem is introduced, and its realization is described. In the first step, an application-specializable soft-core processor is presented that is capable of solving problems while adhering to hard real-time deadlines. This is achieved by the full design time analyzability of the soft-core processor. Its special architecture and other necessary features are discussed. Furthermore, a method for the optimized generation of partial bitstreams for the DPR as well as its practical implementation in a tool is presented. This tool is able to minimize given bitstreams with the help of a differential frame bitmap. Experiments that realize the DPR within the soft-core framework are presented, with respect to the need for hard real-time capability. Those experiments show a significant resource reduction of about 40% compared to a functionally equivalent non-DPR design

eXRUP: a hybrid software development model for small to medium scale projects

The conventional and agile software development process models are proposed and used nowadays in software industry to meet emergent requirements of the customers. Conventional software development models such as Waterfall, V model and RUP have been predominant in industry until mid 1990s, but these models are mainly focused on extensive planning, heavy documentation and team expertise which suit only to medium and large scale projects. The Rational Unified Process is one of the widely used conventional models. Agile process models got attention of the software industry in last decade due to limitations of conventional models such as slow adaptation to rapidly changing business requirements and they overcome problems of schedule and cost. Extreme Programming is one of the most useful agile methods that provide best engineering practices for a good quality product at small scale. XP follows the iterative and incremental approach, but its key focus is on programming, and reusability becomes arduous. In this paper, we present characteristics, strengths, and weaknesses of RUP and XP process models, and propose a new hybrid software development model eXRUP (eXtreme Programming and Rational Unified Process), which integrates the strengths of RUP and XP while suppressing their weaknesses. The proposed process model is validated through a controlled case study

Сутність поняття "витрати основної діяльності промислового підприємства"

Розглянуто підходи науковців до визначення поняття "витрати основної діяльності промислового підприємства"