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Requirements Problem and Solution Concepts for Adaptive Systems Engineering

Requirements Engineering (RE) focuses on eliciting, modelling, and analyzing the requirements and environment of a system-to-be in order to design its specification. The design of the specification, usually called the Requirements Problem (RP), is a complex problem solving task, as it involves, for each new system-to-be, the discovery and exploration of, and decision making in,…

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Agile Requirements Evolution 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…

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An Overview of Requirements Evolution

Changing requirements are widely regarded as one of the most significant risks for software systems development. However, in today’s business landscape, these changing requirements also represent opportunities to exploit new and evolving business conditions. In consonance with other agile methods, we advocate requirements engineering techniques that embrace and accommodate requirements change. This agile approach to…

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The Requirements Problem for Adaptive Systems

Requirements Engineering (RE) focuses on eliciting, modeling, and analyzing the requirements and environment of a system-to-be in order to design its specification. The design of the specification, known as the Requirements Problem (RP), is a complex problem-solving task because it involves, for each new system, the discovery and exploration of, and decision making in a…

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Adaptability of Process-based Service Compositions

When implementing (semi-)automatic business processes with services, engineers are facing two sources of variability. One source of variability are alternative refinements and decompositions of requirements. The other source of variability is that various (combinations of) services can be used to satisfy the same requirements. We suggest a method based on the use of a goal…

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Finding Incremental Solutions for Evolving Requirements

This paper investigates aspects of the problem of software evolution resulting from top-level requirements change. In particular, while most research on design for software focuses on finding some correct solution, this ignores that such a solution is often only correct in a particular, and often short-lived, context. Using a logic-based goal-oriented requirements modeling language, the…

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Requirements Engineering for Self-Adaptive Systems: Core Ontology and Problem Statement

The vision for self-adaptive systems (SAS) is that they should continuously adapt their behavior at runtime in response to changing user’s requirements, operating contexts, and resource availability. Realizing this vision requires that we understand precisely how the various steps in the engineering of SAS depart from the established body of knowledge in information systems engineering….

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Mixed-Variable Requirements Roadmaps for Adaptive Systems

The requirements roadmap concept is introduced as a solution to the problem of the requirements engineering of adaptive systems. The concept requires a new general definition of the requirements problem which allows for quantitative (numeric) variables, together with qualitative (binary boolean) propositional variables, and distinguishes monitored from controlled variables for use in control loops. We…

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Context-Driven Autonomic Adaptation of Service Level Agreements

Service Level Agreements (SLAs) are used in Service-Oriented Computing to define the obligations of the parties involved in a transaction. SLAs define the service users’ Quality of Service (QoS) requirements that the service provider should satisfy. Requirements defined once may not be satisfiable when the context of the web services changes (e.g., when requirements or…

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Engineering Pluripotent Information Systems

A pluripotent information system is an open and distributed information system that (i) automatically adapts at runtime to changing operating conditions, and (ii) satisfies both the requirements anticipated at development time, and those unanticipated before but relevant at runtime. Engineering pluripotency into an information system therefore responds to two recurring critical issues: (i) the need…

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Continually Learning Optimal Allocations of Services to Tasks

Open service-oriented systems which autonomously and continually satisfy users’ service requests to optimal levels are an appropriate response to the need for increased automation of information systems. Given a service request, an open service-oriented system interprets the functional and nonfunctional requirements laid out in the request and identifies the optimal selection of services-that is, identifies…

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Dynamic Web Service Composition within a Service-Oriented Architecture

Increasing automation requires open, distributed, service-oriented systems capable of multicriteria-driven, dynamic adaptation for appropriate response to changing operating conditions. We combine a simple architecture with a novel algorithm to enable openness, distribution, and multi-criteria-driven service composition at runtime. The service-oriented architecture involves mediator Web services coordinating other Web services into compositions necessary to fulfill user…

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Dynamic Requirements Specification for Adaptable and Open Service-Oriented Systems

It is not feasible to engineer requirements for adaptable and open service-oriented systems (AOSS) by specifying stakeholders’ expectations in detail during system development. Openness and adaptability allow new services to appear at runtime so that ways in, and degrees to which the initial functional and nonfunctional requirements will be satisfied may vary at runtime. To…