7987492
Reconsidering the "Software Crisis": A Study of Hypermedia Systems Development
With the advent and growth of the Web, hypermedia information systems have propagated within and beyond organizations. Much concern has been expressed about the quality of hypermedia systems being developed and the apparent absence of disciplined development practices. There has been talk that the infamous “software crisis” is afflicting hypermedia systems development, allegedly brought about by shoddy project management, inadequate requirements analysis and planning, and ad hoc “quick and dirty” development approaches. This paper reports on the findings of a survey of 438 organisations in Ireland, the objectives of which were to test the validity of assertions of a “hypermedia crisis”, and to explore what mechanisms if any are being used to guide and control hypermedia systems development. The preliminary conclusions are that hypermedia development is much more disciplined that popularly believed, and the state of practice is much healthier than depicted by many academic researchers.
16451824
Web-based systems design: a study of contemporary practices and an explanatory framework based on “method-in-action”
This paper reports the findings of a detailed study of Web-based systems design (WBSD) practices in Ireland based on data collected over a 3-year period (2002–2005), the objectives of which were to (1) contribute towards a richer understanding of the current “real-world” context of WBSD by characterising the profile of a typical project (team size, timeframe, nature of requirements, etc.) and identifying the key challenges, constraints, and imperatives (i.e. “mediating factors”) faced by Web-based system designers, and (2) understand how those contextual parameters and mediating factors influence the activity of WBSD as regards the selection and enactment of whatever design practices are therefore engaged (i.e. the use of methods, procedures, etc.). Data was gathered through a survey which yielded 165 usable responses, and later through a series of semi-structured qualitative interviews. Using grounded theory, an explanatory conceptual framework is derived, based on an extension of the “method-in-action” model, the application of which to WBSD has not been previously investigated in depth. It is proposed that this framework of WBSD issues is valuable in a number of ways to educators, researchers, practitioners, and method engineers.
18739764
New Branches, Old Roots: A Study of Methods and Techniques in Web/Hypermedia Systems Design
Abstract Despite claims in the literature that “traditional” methods and techniques are inadequate and poorly matched to the demands of the Web design context, the findings from a field survey of Web/hypermedia systems designers in Ireland indicate quite the contrary. in general, the notion of “method” in the traditional sense seems to have been largely displaced by hybrid aggregations of techniques and other method fragments – selected on the basis of usefulness and purposefully blended within an overarching framework of an in-house development process.
11728820
The Hugin Tool for Probabilistic Graphical Models
As the framework of probabilistic graphical models becomes increasingly popular for knowledge representation and inference, the need for efficient tools for its support is increasing. The Hugin Tool is a general purpose tool for construction, maintenance, and deployment of Bayesian networks and influence diagrams. This paper surveys the key functionality of the Hugin Tool and reports on new advances of the tool. Furthermore, an empirical analysis reports on the efficiency of the Hugin Tool on common inference and learning tasks.
34671312
Hugin - The Tool for Bayesian Networks and Influence Diagrams
120859220
Analysis of trapped entanglements in polymer networks
This work reviews different standard methods to analyze trapped entanglements of polymer networks and discusses their advantages and drawbacks with respect to simplicity, computing time and accuracy of the results. Since this standard analysis is based on the pairwise test of closed cycles, two algorithms for the determination of these cycles are introduced and compared. The decomposition into meshes creates unsolved problems regarding the non-ambiguity and the completeness of the received results. Examples are given in order to show their effects and to start further discussion to receive more convenient methods. As one possible solution Vassiliev's invariants are discussed and an approximation method is introduced to correct the possible multiple counting of entanglements.
53225813
Architecture - A performance comparison through benchmarking and modeling of three leading supercomputers: blue Gene/L, Red Storm, and Purple
14275613
An empirical performance analysis of commodity memories in commodity servers
This work details a performance study of six different types of commodity memories in two commodity server nodes. A number of micro-benchmarks are used that measure low-level performance characteristics, as well as two applications representative of the ASC workload. The memories vary both in terms of performance, including latency and bandwidths, and in terms of their physical properties and manufacturer. The two server nodes analyzed were an Itanium-II Madison based system, and a Xeon based system. All memories can be used within both of these processing nodes. This allows the performance of the memories to be directly examined while keeping all other factors within a node the same (processor, motherboard, operating system etc.). The results of this study show that there can be a significant difference in application performance depending on the actual memory used - by as much as 20%. The achieved performance is a result of the integration of the memory into the node as well as how the applications actually utilize it.