Component-based Adaptation Methods for Service-Oriented Peer-to-Peer Software Architectures

Service-oriented peer-to-peer architectures aim at supporting application scenarios of dispersed collaborating groups in which the participating users are capable of providing and consuming local resources in terms of peer services. From a conceptual perspective, service-oriented peer-to-peer architectures adopt relevant concepts of two well-established state-of-the-art software architectural styles, namely service-oriented architectures (also known as SOA) and peer-to-peer architectures (P2P). One major argumentation of this thesis is that the adoption of end-user adaptability (or tailorability) concepts is of major importance for the successful deployment of service-oriented peer-to-peer architectures that support user collaboration. Since tailorability concepts have so far not been analyzed for both peer-to-peer and service-oriented architectures, no relevant models exist that could serve as a tailorability model for service-oriented peer-to-peer architectures. In order to master the adaptation of peer services, as well as peer service compositions within service-oriented peer-to-peer architectures, this dissertation proposes the adoption of component-oriented development methods. These so-called component-based adaptation methods enable service providers to adapt their provided services during runtime. Here, a model for analyzing existing dependencies on subscribed ser-vice consumers ensures that a service provider is able to adapt his peer services without violating any dependencies. In doing so, an adaptation policy that can be pre-arranged within a peer group regulates the procedures of how to cope with existing dependencies in the scope of a group. The same methods also serve as a way to handle exceptional cases, in particular the failure of a dependent service provider peer and, hence, a service that is part of a local service composition. In this, the hosting runtime environment is responsible for detecting exceptions and for initiating the process of exception resolution. During the resolution phase, a user can be actively involved at selected decision points in order to resolve the occurred exception in unpredictable contexts. An exception could also be the reason for the violation of an integrity constraint that serves as a contract between various peers that interact within a given collaboration. The notion of integrity constraints and the model of handling the constraint violation aim at improving the reliability of target-oriented peer collaborations. This dissertation is composed of three major parts that each makes a significant contribution to the state of the art. First of all, a formal architectural style (SOP2PA) is introduced to define the fundamental elements that are necessary to build service-oriented peer-to-peer architectures, as well as their relationships, constraints, and operational semantics. This architectural style also formalizes the above-mentioned adaptation methods, the exception handling model that embraces these methods, the analysis model for managing consumer dependencies, as well as the integrity constraints model. Subsequently, on this formal basis, a concrete (specific) service-oriented peer-to-peer architecture (DEEVOLVE) is conceptualized that serves as the default implementation of that style. Here, the notions described above are materialized based on state-of-the-art software engineering methods and models. Finally, the third contribution of this work outlines an application scenario stemming from the area of construction informatics, in which the default implementation DEEVOLVE is deployed in order to support dispersed planning activities of structural engineers

HIVE-MIND SPACE: A META-DESIGN APPROACH FOR CULTIVATING AND SUPPORTING COLLABORATIVE DESIGN.

The ever-growing complexity of design projects requires more knowledge than any individual can have and, therefore, needs the active engagement of all stakeholders in the design process. Collaborative design exploits synergies from multidisciplinary communities, encourages divergent thinking, and enhances social creativity. The research documented in this thesis supports and deepens the understanding of collaborative design in two dimensions: (1) It developed and evaluated socio-technical systems to support collaborative design projects; and (2) It defined and explored a meta- design framework focused on how these systems enable users, as active contributors, to modify and further develop them. The research is grounded in and simultaneously extends the following major dimensions of meta-design: (1) It exploits the contributions of social media and web 2.0 as innovative information technologies; (2) It facilitates the shift from consumer cultures to cultures of participation; (3) It fosters social creativity by harnessing contributions that occur in cultures of participation; (4) It empowers end-users to be active designers involved in creating situated solutions. In a world where change is the norm, meta-design is a necessity rather than a luxury because it is impossible to design software systems at design time for problems that occur only at use time. The co-evolution of systems and users\u2bc social practices pursued in this thesis requires a software environment that can evolve and be tailored continuously. End-user development explores tools and methods to support end users who tailor software artifacts. However, it addresses this objective primarily from a technical perspective and focuses mainly on tailorability. This thesis, centered on meta-design, extends end-user development by creating social conditions and design processes for broad participation in design activities both at design time and at use time. It builds on previous research into meta- design that has provided a strategic overview of design opportunities and principles. And it addresses some shortcomings of meta-design, such as the lack of guidelines for building concrete meta-design environments that can be assessed by empirical evaluation. Given the goal of this research, to explore meta-design approaches for cultivating and supporting collaborative design, the overarching research question guiding this work is: How do we provide a socio-technical environment to bring multidisciplinary design communities together to foster creativity, collaboration, and design evolution? 8 To answer this question, my research was carried out through four different phases: (1) synthesizing concepts, models, and theories; (2) framing conceptual models; (3) developing several systems in specific application areas; and (4) conducting empirical evaluation studies. The main contributions of this research are: \uf0a7 The Hive-Mind Space model, a meta-design framework derived from the \u201csoftware shaping workshop\u201d methodology and that integrates the \u201cseeding, evolutionary growth, reseeding\u201d model. The bottom-up approach inherent in this framework breaks down static social structures so as to support richer ecologies of participation. It provides the means for structuring communication and appropriation. The model\u2bcs open mediation mechanism tackles unanticipated communication gaps among different design communities. \uf0a7 MikiWiki, a structured programmable wiki I developed to demonstrate how the hive-mind space model can be implemented as a practical platform that benefits users and how its features and values can be specified so as to be empirically observable and assessable; \uf0a7 Empirical insights, such as those based on applying MikiWiki to different collaborative design studies, provide evidence that different phases of meta-design represent different modes rather than discrete levels

Groupware design : principles, prototypes, and systems

Computers are valuable tools for a wide range of work tasks. A substantial limitation on their value, however, is the predominant focus on enhancing the work of individuals. This fails to account for the issues of collaboration that affect almost all work. Research into computer supported cooperative work (CSCW) aims to eliminate this deficiency, but the promise of computer systems for group work has not been met. This thesis presents four design principles that promote the development of successful groupware. The principles identify the particular problems encountered by groupware, and provide guidelines and strategies to avoid, overcome, or minimise their impact. Derived from several sources, the major influence on the principles development is an investigation into the relationship between factors affecting groupware failure. They are stimulated by observations of groupware use, and by design insights arising from the development of two groupware applications and their prototypes: Mona and TELEFREEK. Mona provides conversation-based email management. Several groupware applications allow similar functionality, but the design principles result in Mona using different mechanisms to achieve its user-support. TELEFREEK provides a platform for accessing computer-supported communication and collaboration facilities. It attends to the problems of initiating interaction, and supports an adaptable and extendible set of "social awareness" assistants. TELEFREEK offers a broader range of facilities than other groupware, and avoids the use of prohibitively high-bandwidth communication networks. TELEFREEK demonstrates that much can be achieved through current and widely accessible technology. Together, Mona and TELEFREEK forcefully demonstrate the use of the design principles, and substantiate the claim of their utility

An analysis framework for CSCW systems

Software toolkits are under development to help construct applications that support group-working. Toolkit developers adopt different approaches to group-work support in order to tackle different issues and a toolkit is commonly characterised by the approach adopted. It is difficult to compare toolkits because of this lack of apparent commonality and it is difficult to decide which toolkits meet specific application requirements. [Continues.

Un-constraining the medium: design software systems to support situated action

This dissertation is concerned with Computer Supported Cooperative Work (CSCW) and in particular with ways in which insights from ethnomethodology can be melded into the design of CSCW systems—a relationship that has been labelled technomethodology. The dissertation outlines a number of possible ways in which system design can learn from ethnomethodology and concentrates on one particular aspect—namely that CSCW should look closely at its foundational assumptions and, if necessary, re-specify any concepts which appear problematic in their formulation. [Continues.

Corroborating Emotion Theory with Role Theory and Agent Technology: a Framework for Designing Emotional Agents as Motivational Tutoring Entities

Nowadays, more and more applications require systems that can interact with humans. Agents can be perceived as computing services that humans, or even other agents, can request in order to accomplish their tasks. Some services may be simple and others rather complex. A way to determine the best agents (services) to be implemented is to identify who the actors are in the object of study, which roles they play, and (if possible) what kind of knowledge they use. Socially Intelligent Agents (SIAs) are agent systems that are able to connect and interface with humans, i.e. robotic or computational systems that show aspects of human-style social intelligence. In addition to their relevance in application areas such as e-commerce and entertainment, building artefacts in software and hardware has been recognized as a powerful tool for establishing a science of social minds which is a constructive approach toward understanding social intelligence in humans and other animals. Social intelligence in humans and other animals has a number of fascinating facets and implications for the design of SIAs. Human beings are biological agents that are embodied members of a social environment and are autobiographic agents who have a unique personality. They are situated in time and space and interpret new experiences based on reconstructions of previous experiences. Due to their physical embodiment, they have a unique perspective on the world and a unique history: an autobiography. Also, humans are able to express and recognize emotions, that are important in regulating individual survival and problem-solving as well as social interactions. Like artificial intelligence research trend, SIA research trend can be pursued with different goals in mind. A deep AI approach seeks to simulate real social intelligence and processes. A shallow AI approach, which will be highlighted also within this thesis, aims to create artefacts that are not socially intelligent per se, but rather appear socially intelligent to a given user. The shallow approach does not seek to create social intelligence unless it is meaningful social intelligence vis-à-vis some user situation In order to develop believable SIAs we do not have to know how beliefs-desires and intentions actually relate to each other in the real minds of the people. If one wants to create the impression of an artificial social agent driven by beliefs and desires, it is enough to draw on investigations on how people with different cultural background, develop and use theories of mind to understand the behaviours of others. Therefore, SIA technology needs to model the folk-theory reasoning rather than the real thing. To a shallow AI approach, a model of mind based on folk-psychology is as valid as one based on cognitive theory. Distance education is understood as online learning that is technology-based training which encompasses both computer-assisted and Web-based training. These systems, which appear to offer something for everyone at any time, in any place, do not always live up to the great promise they offer. The usage of social intelligent agents in online learning environments can enable the design of “enhanced-learning environments” that allow for the development and the assessment of social competences as well as the common professional competences. Within this thesis it is shown how to corroborate affective theory with role theory with agent technology in a synchronous virtual environment in order to overcome several inconveniences of distance education systems. This research embraces also the shallow approach of SIA and aims to provide the first steps of a method for creating a believable life-like tutor agent which can partially replace human-teachers and assist the students in the process of learning. The starting point for this research came from the fact: anxious, angry or depressed students do not learn; people in these conditions do not absorb information efficiently, consequentially it is an illusion to think that learning environments that do not consider motivational and emotional factors are adequate