Quality of Service Contract Specification, Establishment, and Monitoring for Service Level Management

This paper describes a Quality of Service (QoS) management approach and architecture as well as a case study for Service Level Management (SLM). Our approach brings in a new perspective to the SLM probem by using QoS management and QoS Contract specification, establishment, and monitoring. In SLM, the service consumer side and the service provider side must share a common understanding of QoS characteristics and use a common language for specifying desired QoS parameters in the form of QoS contracts. A service consumer must negotiate with the service provider to establish mutually agreed QoS contracts for an interaction session. When establising a new QoS contract, the service provider must consider both QoS contracts already agreed upon with existing consumers and system resource conditions. Similarly, a service consumer must be prepared in revising its contract with the service provider as conditions change over time. Once a QoS contract is established, SLM must monitor QoS status to make sure that the service quality is provided at the agreed range. If necessary, SLM must activate adaptation mechanisms to bring the service quality to the desired level. A case study is presented in this paper to validate the QoS contract management design approach and architecture for SLM.

Independent Living and Attendant care in Sweden: A Consumer Perspective

[Excerpt] One of the main aims of the growing Independent Living Movement , the international civil rights movement of people with disabilities, has been to gain control over the services that are necessary for participating in society on equal terms. Of these services attendant care has been identified by the movement as perhaps the most critical prerequisite for a dignified and productive life for persons with severe disabilities

10021 Abstracts Collection -- Service-Oriented Architecture and (Multi-)Agent Systems Technology

From 10.01. to 15.01.2010, Dagstuhl Seminar 10021 ``Service-Oriented Architecture and (Multi-)Agent Systems Technology \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Dynamic Assembly for System Adaptability, Dependability, and Assurance

(DASASA) ProjectAuthor-contributed print ite

The specification of a consumer design toolkit to support personalised production via additive manufacturing

This thesis stems from the future scenario that as additive manufacturing (AM) technologies become cheaper and more readily available, consumers without formal design training will begin to customise, design and manufacture their own products. Much of this activity is likely to infringe on brands' intellectual property. The research explores the feasibility of a situation in which, rather than attempting to prohibit such activity, manufacturers engage with consumers to facilitate it, thus retaining control (albeit reduced) over their brand's image and the quality of products offered. The research begins with a literature review encompassing AM technologies and their adoption by consumers; mass customisation (MC) and the management of variation in product offering; and traditional models of industrial design (ID), including user-centred design and co-design. It finds that conventional definitions of MC and ID are unable to provide for the possibility of consumer intervention in the shape and non-modular configuration of products. Further research was then conducted in the areas of Open Design (including crowdsourcing, open sourcing and 'hardware hacking') as well as bespoke customisation, which were found to be much more accommodating of the scenario proposed. A new term, 'consumer design', is introduced and defined, together with the hypothesis that in future, the role of the industrial designer may be to design 'unfinished' products. An original classification of consumer involvement in ID is presented. Empirical research, undertaken with consumers using an iterative design software package (Genoform), demonstrated a preference for designing within pre-determined boundaries. Action research was conducted to assess consumer-oriented 3D CAD software, and compare its capabilities with that of MC toolkits. A survey of senior designers and brand managers revealed strategies for implementing and managing a brand's product design language, and a guide was created to show the relative importance of designed features. Using these findings, a prototype toolkit was created to demonstrate how a brand might facilitate consumer interaction with the shape design of a complex consumer electronics product (in this case a mobile phone). The toolkit was tested with both consumers and experienced designers to assess its viability. The research finds that it is possible to create a consumer-design toolkit which enables untrained users to change the form of a product, whilst maintaining brand equity and ensuring the product's functionality and manufacturability

Prosumer behaviour in emerging electricity systems

This dissertation investigates the interface between technology and society in the emerging electricity systems and in particular the role of the energy prosumer in the energy transition. It contributes to the understanding of the role of consumers in emerging electricity systems within the current EU energy policy context where consumer active participation is regarded as "a prerequisite for managing the energy transition successfully and in a cost-effective way". Emerging energy systems are characterized by a high level of complexity, especially for what concerns the behaviour of social actors. Social actors interact through physical and social networks by sharing information and learning from one another through social interactions. These interactions determine self-organization and emergent behaviours in energy consumption patterns and practices. I argue that the best suited tool to study emergent behaviours in energy consumption patterns and practices, and to investigate how consumers' preferences and choices lead to macro behaviours is agent based modelling. To build a sound characterization of the energy prosumer, I review the current social psychology and behavioural theories on sustainable consumption and collect evidence from EU energy prosumers surveys, studies and demand side management pilot projects. I employ these findings to inform the development of an agent based model of the electricity prosumer, Subjective Individual Model of Prosumer – SIMP, and its extended version, SIMP-N, that includes the modelling of the social network. I apply SIMP and SIMP-N models to study the emergence in consumer systems and how values and beliefs at consumer level (as defined by social psychology and behavioural theories and informed by empirical evidence) and social dynamics lead to macro behaviours. More specifically, I explore the diffusion of smart grid technologies enabled services among a population of interacting prosumers and evaluate the impact of such diffusion on individual and societal performance indicators under different policy scenarios and contextual factors. The analysis of the simulation results provides interesting insights on how different psychological characteristics, social dynamics and technological elements can strongly influence consumers' choices and overall system performance. I conclude proposing a framework for an integrated approach to modelling emerging energy systems and markets that extend the SIMP model to also include markets, distribution system operator and the electricity network

A survey on quality attributes in servicebased systems

Service-based systems have become popular in the software industry. In software engineering, it is widely acknowledged that requirements on quality attributes (e.g., performance, security, reliability) significantly impact the design of software systems. This study explores the role of quality attributes during the design of service-based systems. We investigate the significance of quality attributes when designing service-based systems and how quality attributes are addressed through design decisions, across application domains, and related to other aspects of software development, e.g., architecture documentation. We conducted a descriptive survey. The survey was done as an online questionnaire targeting practitioners. Furthermore, we included researchers with practical design experience. We obtained 56 valid responses. Most survey participants consider quality attributes and functionality as equally important and treat quality attributes explicitly rather than implicitly. Furthermore, dependability is the most relevant quality attribute in service-based systems; we do not find quality attributes that are particularly important in specific application domains. Most quality attributes are addressed by ad hoc decisions, rather than established architecture or design patterns or technologies. Only few decision alternatives are considered when making architectural decisions to address quality attributes. Our results partially confirm anecdotal evidence from current literature, but also strengthen previous claims by providing empirical evidence. Our results point to future research directions (e.g., exploring the impact of decision types on how well quality attributes can be achieved) and implications for practitioners (e.g., training makes a difference to how quality attributes are treated).Peer ReviewedPostprint (author’s final draft

Extended Fault Taxonomy of SOA-Based Systems

Service Oriented Architecture (SOA) is considered as a standard for enterprise software development. The main characteristics of SOA are dynamic discovery and composition of software services in a heterogeneous environment. These properties pose newer challenges in fault management of SOA-based systems (SBS). A proper understanding of different faults in an SBS is very necessary for effective fault handling. A comprehensive three-fold fault taxonomy is presented here that covers distributed, SOA specific and non-functional faults in a holistic manner. A comprehensive fault taxonomy is a key starting point for providing techniques and methods for accessing the quality of a given system. In this paper, an attempt has been made to outline several SBSs faults into a well-structured taxonomy that may assist developers to plan suitable fault repairing strategies. Some commonly emphasized fault recovery strategies are also discussed. Some challenges that may occur during fault handling of SBSs are also mentioned