166,514 research outputs found
Two Case Studies of Subsystem Design for General-Purpose CSCW Software Architectures
This paper discusses subsystem design guidelines for the software architecture of general-purpose computer supported cooperative work systems, i.e., systems that are designed to be applicable in various application areas requiring explicit collaboration support. In our opinion, guidelines for subsystem level design are rarely given most guidelines currently given apply to the programming language level. We extract guidelines from a case study of the redesign and extension of an advanced commercial workflow management system and place them into the context of existing software engineering research. The guidelines are then validated against the design decisions made in the construction of a widely used web-based groupware system. Our approach is based on the well-known distinction between essential (logical) and physical architectures. We show how essential architecture design can be based on a direct mapping of abstract functional concepts as found in general-purpose systems to modules in the essential architecture. The essential architecture is next mapped to a physical architecture by applying software clustering and replication to achieve the required distribution and performance characteristics
Systematic composition of distributed objects: Processes and sessions
We consider a system with the infrastructure for the creation and interconnection of large numbers of distributed persistent objects. This system is exemplified by the Internet: potentially, every appliance and document on the Internet has both persistent state and the ability to interact with large numbers of other appliances and documents on the Internet. This paper elucidates the characteristics of such a system, and proposes the compositional requirements of its corresponding infrastructure. We explore the problems of specifying, composing, reasoning about and implementing applications in such a system. A specific concern of our research is developing the infrastructure to support structuring distributed applications by using sequential, choice and parallel composition, in the anarchic environment where application compositions may be unforeseeable and interactions may be unknown prior to actually occurring. The structuring concepts discussed are relevant to a wide range of distributed applications; our implementation is illustrated with collaborative Java processes interacting over the Internet, but the methodology provided can be applied independent of specific platforms
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Web-based information systems development and dynamic organisational change: the need for emergent development tools
This paper considers contextual issues relating to the problem of developing web-based information
systems in and for emergent organisations. It postulates that the methods available suffer because of
sudden and unexpected changing characteristics within the organisation. The Theory of Deferred
Action is used as the basis for the development of an emergent development tool. Many tools for
managing change in a continuously changing organisation are susceptible to inadequacy. The insights
proposed are believed to assist designers in developing functional and relevant approaches within
dynamic organisational contexts
Visual communication in urban planning and urban design
This report documents the current status of visual communication in urban design and planning. Visual communication is examined through discussion of standalone and network media, specifically concentrating on visualisation on the World Wide Web(WWW).Firstly, we examine the use of Solid and Geometric Modelling for visualising urban planning and urban design. This report documents and compares examples of the use of Virtual Reality Modelling Language (VRML) and proprietary WWW based Virtual Reality modelling software. Examples include the modelling of Bath and Glasgow using both VRML 1.0 and 2.0. A review is carried out on the use of Virtual Worldsand their role in visualising urban form within multi-user environments. The use of Virtual Worlds is developed into a case study of the possibilities and limitations of Virtual Internet Design Arenas (ViDAs), an initiative undertaken at the Centre for Advanced Spatial Analysis, University College London. The use of Virtual Worlds and their development towards ViDAs is seen as one of the most important developments in visual communication for urban planning and urban design since the development plan.Secondly, photorealistic media in the process of communicating plans is examined.The process of creating photorealistic media is documented, examples of the Virtual Streetscape and Wired Whitehall Virtual Urban Interface System are provided. The conclusion is drawn that although the use of photo-realistic media on the WWW provides a way to visually communicate planning information, its use is limited. The merging of photorealistic media and solid geometric modelling is reviewed in the creation of Augmented Reality. Augmented Reality is seen to provide an important step forward in the ability to quickly and easily visualise urban planning and urban design information.Thirdly, the role of visual communication of planning data through GIS is examined interms of desktop, three dimensional and Internet based GIS systems. The evolution to Internet GIS is seen as a critical component in the development of virtual cities which will allow urban planners and urban designers to visualise and model the complexity of the built environment in networked virtual reality.Finally a viewpoint is put forward of the Virtual City, linking Internet GIS with photorealistic multi-user Virtual Worlds. At present there are constraints on how far virtual cities can be developed, but a view is provided on how these networked virtual worlds are developing to aid visual communication in urban planning and urban design
Towards a re-engineering method for web services architectures
Recent developments in Web technologies – in particular
through the Web services framework – have greatly enhanced the flexible and interoperable implementation of service-oriented software architectures. Many older Web-based and other distributed software systems will be re-engineered to a Web services-oriented platform. Using an advanced
e-learning system as our case study, we investigate central aspects of a re-engineering approach for the Web services platform. Since our aim is to provide components of the legacy system also as services in the new platform, re-engineering to suit the new development paradigm is as important as re-engineering to suit the new architectural requirements
An integrated approach to preparing, publishing, presenting and preserving theses
[Abstract]: This paper describes progress on a project funded by the Australian government to create Free
software; the Integrated Content Environment for research and scholarship (ICE-RS). ICE-RS is a
multi-faceted project which will add value to finished theses by making them available in both
HTML and PDF, as well as providing a mechanism for packaging multimedia theses. The project
will also concentrate on providing services for thesis production, with version control, automated
backup and collaboration services.
The paper begins with the established content management system that is the basis for the
project, ICE-RS , originally developed to create courseware packages. ICE includes distributed, version
controlled collaboration, using word processing software and works on multiple platforms, with
standard document formats. We survey other approaches to content authoring and publishing for
ETDs.
We showcase exploratory work on integration of the thesis writing process with Institutional
Repository software including publishing theses in both PDF and HTML with preservation and
descriptive metadata. The presentation will include demonstrations of thesis production at all stages
of development from proposal to completion.
In a more speculative vein, we will discuss opportunities for institutions to provide new levels of
support for candidates via automated thesis “dashboard” progress reports, supervisor and examiner
annotation and comment and support for copyright considerations as early as possible in the
process
DRIVER Technology Watch Report
This report is part of the Discovery Workpackage (WP4) and is the third report out of four deliverables. The objective of this report is to give an overview of the latest technical developments in the world of digital repositories, digital libraries and beyond, in order to serve as theoretical and practical input for the technical DRIVER developments, especially those focused on enhanced publications. This report consists of two main parts, one part focuses on interoperability standards for enhanced publications, the other part consists of three subchapters, which give a landscape picture of current and surfacing technologies and communities crucial to DRIVER. These three subchapters contain the GRID, CRIS and LTP communities and technologies. Every chapter contains a theoretical explanation, followed by case studies and the outcomes and opportunities for DRIVER in this field
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