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The purpose of this paper is to propose a four‐level hierarchy model for multimedia documents representation to be used during the dynamic scheduling and altering of multimedia contents.

The four‐level hierarchy model (object, operation, timing, and precedence), offers a fine‐grain representation of multimedia contents and is embedded within a research tool, which is called WEBCAP. WEBCAP utilizes the four‐level hierarchy to synchronize the retrieval of objects in the multimedia document employing Allen's temporal relations, and then applies the Bellman‐Ford's algorithm on the precedence graph to schedule all operations (fetch, transmit, process, and render), while satisfying the in‐time updating and all web workload's resources constraints.

The experimental results demonstrate the effectiveness of the model in scheduling the periodical updating multimedia documents while considering a variety of workloads on web/TCP.

WEBCAP should be enhanced to automatically measure and/or approximate the available bandwidth of the system using sophisticated measurement of end‐to‐end connectivity. In addition, WEBCAP should be expanded and enhanced to examine system infrastructure for more real‐time applications, such as tele‐medicine and e‐learning.

WEBCAP can be used as an XML markup language for describing multimedia presentations. It can be used to create online presentations similar to PowerPoint on desktop environment, or used as an interactive e‐learning tool. An HTML browser may use a WEBCAP plug‐in to display a WEBCAP document embedded in an HTML/XML page.

This paper proposed a dynamic scheduling of multimedia documents with frequent updates taking into consideration the network's workload to reduce the packet lost ratio in the TCP flow, especially in the early stages. WEBCAP can be used to guide distributed systems designers/managers to schedule or tune their resources for optimal or near optimal performance, subject to minimizing the cost of document retrieval while satisfying the in time constraints.

Realistic force sensation can help operators better feel and manipulate parts for virtual assembly (VA). Moreover, for VA of mechanical parts, it is necessary to consider their tolerance levels so as to apply proper assembly forces. Out of the three common assembly fit types, the type of clearance fit is the focus of virtual manual assembly, as parts with such fit type require precise force feedback to assist users’ assembly operations.

This study proposes a novel force rendering model for VA of mechanical parts with clearance fits. By decomposing an actual assembly operation into three consecutive states, the corresponding forces are formulated.

A prototype system is designed and developed to implement the model, and comparative case studies are conducted to investigate the users’ performance with the other three common approaches, namely, a typical WIMP (window-icon-menu-pointer) interface with CAD software, a physics simulation with collision detection and the approach that combines physics simulation and geometric constraints restriction. The results have shown that the proposed model is more realistic by providing continuous and realistic force feedback to the users.

The users’ feeling of immersion and their operational efficiency are greatly enhanced with the force sensation provided.

After establishing the terminology, shows how the choice of the name of the subject of a document and the rendering of the name in the heading of the specific subject entry can be got by facet analysis based on postulates and principles. After showing that subject headings constitute an artificial language, points out that using facet analysis for subject heading does not amount to using class number. Marks out the area for an objective statistical survey of sought heading for subject entry. Calls on Council for Library Resources Incorporated to provide for this project.

Owing to the numerous part models and massive datasets used in automobile assembly design, virtual assembly software cannot simulate a whole vehicle smoothly in real time. For this reason, implementing a new virtual assembly environment for massive complex datasets would be a significant achievement. The paper aims to focus on this problem.

A new system named “Grid‐enabled collaborative virtual assembly environment” (GCVAE) is proposed in the paper, and it comprises three parts: a private grid‐based support platform running on an inner network of enterprise; a service‐based parallel rendering framework with a sort‐last structure; and a multi‐user collaborative virtual assembly environment. These components would aggregate the idle resources in an enterprise to support assembly simulation with a large complex scene of whole vehicle.

The system prototype proposed in the paper has been implemented. The following simulations show that it can support a complex scene in a real‐time mode by using existing hardware and software, and can promote the efficient usage of enterprise resources.

Using the GCVAE, it is possible to aggregate the idle resources in an enterprise to run assembly simulations of a whole automobile with massively complex scenes, thus observably reducing fault occurrence rates in future manufacturing.

The paper introduces a new grid‐enabled methodology into research on collaborative virtual assembly system which can make the best use of idle resources in the enterprise to support assembly simulations with massively complex product models. A video‐stream‐based method was used to implement the system; this enables designers to participate ubiquitously in the simulation to evaluate the assembly of the whole automobile without hardware limitations.

We present recent results from an EPSRC funded project VirTex (Virtual Textile Catalogues). The goal of this project is to develop graphics and image‐processing software for the capture, storage, search, retrieval and visualisation of 3D textile samples. The ultimate objective is to develop a web‐based application that allows the user to search a database for suitable textiles and to visualize selected samples using real‐time photorealistic 3D animation. The main novelty of this work is in the combined use of photometric stereo and real‐time per‐pixel‐rendering for the capture and visualisation of textile samples. Photometric stereo is a simple method that allows both bump map and colour map of a surface texture to be captured digitally. It uses a single fixed camera to obtain three images under three different illumination conditions. The colour map is the image that would be obtained under diffuse lighting. The bump map describes the small undulations of the surface relief. When imported into a standard graphics program these images can be used to texture 3D models. The appearance is particularly photorealistic, especially under changing illumination and viewpoints. The viewer can manipulate both viewpoint and lighting to gain a deeper perception of the properties of the textile sample. In addition, these images can be used with 3D models of products to provide extremely accurate visualisations for the customer. Until recently, these images could only be rendered using ray‐tracing software. However, recent consumer‐level graphics cards from companies such as Nvidia, ATI and 3Dlabs provide real‐time per‐pixel shading. We have developed software that takes advantage of the advanced rendering features of these cards to render images in real‐time. It uses photometrically acquired bump and colour maps of textiles to provide real‐time visualisation of a textile sample, under user‐controlled illumination, pose and flex.

The purpose of this paper is to present a methodology in order to improve inspections' diagnosis during façades' service life through in‐service criteria. On‐site performance assessment and deciding on the maintenance of renders can only be improved if quantitative parameters are pre‐established at the design stage and monitored under service conditions.

The methodology is based on a set of in‐service parameters inferred from visual observation and measurements and their methods of assessment (based on visual inspections, auxiliary techniques, in‐situ and laboratorial testing). These have been arrived at by inspecting the façade rendering on 44 buildings (cement‐based renders), of different ages and types of degradation.

This paper focuses on 23 proposed mechanical and physical‐chemical parameters that can complement the ones already established by standards or technical data, obtained in lab conditions, using standard specimens or small models. They are assessed by techniques that have been applied to renders or other façade elements such as concrete or timber structures. The reliability of this in‐service performance assessment is discussed together with its potential as an aid to deciding on predictive maintenance action after an inspection's diagnosis.

The originality of this approach stems from the fact that in‐service parameters derived from both laboratory and in‐situ measurements can improve understanding of the behaviour of façade rendering, which is an important step in planning and monitoring maintenance. Two aspects are emphasised: the behaviour of materials/systems is assessed in real conditions, and the subjectivity of in‐service diagnosis is reduced when more than one performance parameter is assessed.

The purpose of this paper is to present a proposal for a methodology to support the rehabilitation project of renders of old buildings.

To achieve the objective it was considered essential to define the main types of participants and aspects to integrate the proposal. The research methodology consists in an inquiry presented to several professional participants in rehabilitation, a market study of materials and products available in Portugal, the design of a methodology proposal and its application to a case study. The inquiry sample totals 24 answers from the targeted professionals. A sequence of relevant supporting procedures consists in the proposal, which aims to provide a supporting methodology to decide and project in this context and also to be tested with its application to the building. This proposal was applied to an old building with load-bearing stone masonry walls and air-lime-based renders.

It was concluded that the assessment of the building and ex+ternal renderings’ condition, its diagnosis and of the supporting walls, the definition of intervention, the specification of materials to be used and performance requirements to comply, and also plans for conservation and periodic maintenance, are crucial. From the inquiry, compatibility between materials and complementary roles and points of view of different types of participants in rehabilitation must be highlighted.

A proposal for a methodology to support the project could provide useful guidance particularly for architects and construction engineers, and improve the understanding of direct participants on site, therefore contributing for the correct implementation of the intervention.

This paper offers a reanalysis or “re‐view” of a celebrated tale of corporate transformation – the turnaround of Sears, Roebuck and Company – which was discussed in the Harvard Business Review. Noting that “contextual” and “processual” attempts to revise the tale of Sears and its transformation would tend to exchange one monological rendering for another, albeit more critical account, the paper “re‐views” the case in an attempt to make space for perspectives and narratives normally edited out of narratives of change management.

Building upon a critical review of the literature concerned with organizational storytelling the paper “re‐views” the Harvard rendering of the Sears case as an epic tale. The paper then supplements this epic rendering of the Sears case with another two accounts of the case, which recast and review the tale first as a tragedy and then as a comedy.

The paper reveals the polysemic nature of organization and change and suggests the need for approaches to the narration of change that can give voice to perspectives denied by both celebratory and critical accounts of change management.

The paper offers an innovative “re‐view” of a celebrated account of change management and invites the reader to make room for voices and perspectives normally lost within narratives of change.

Having been a promising visualization tool since 1950s, ironically, virtual reality is not widely used in the architectural design and evaluation process due to several constrains, such as the high cost of equipments and advanced programming skills required. This paper described the collaboration between design computing courses and architecture design studios that have been taught at Savannah College of Art and Design (SCAD) in 2004 and 2005. These courses explored several practical methods to integrate Low Cost Virtual Reality Aided Design (LC-VRAD) in the architectural design process. As a summary of the collaboration, this paper refers to three main aspects: (1) How to use game engine to design an affordable VR system in the ordinary studio environment. (2) How to integrate VR, into the design process, not only as a visualization tool, but also as a design instrument. (3) How to evaluate different methods of representing architectural models based on the efficiency of workflow, rendering quality and users' feedback.

Support by the Game and Interactive Design Department at SCAD, students in the School of Building Arts implemented two Low Cost VRAD methods in various design phases, starting from site analysis, schematic design, design development to the final presentation. Two popular game engines, Epic Game's Unreal engine and Director MX's Shockwave engine, were introduced to students to visualize their project in real-time. We discussed computer-aided design theories including the application of VR, as well as digital computing and human computer interaction. At the end of each quarter, feedbacks from students and faculties were collected and analyzed. These methods were revised and improved consistently across 2004 and 2005 academic year.

Describes an approach to the processing and presentation of online full‐text journals that utilizes several evolving information technologies, including extensible markup language (XML) and extensible stylesheet language transformations (XSLT). Discusses major issues and trade‐offs associated with these technologies, and also specific lessons learned from our use of these technologies in the Illinois Testbed of full‐text journal articles. Focuses especially on issues associated with the representation of documents in XML, techniques to create and normalize metadata describing XML document instances, XSLT features employed in the Illinois Testbed, and trade‐offs of different XSLT implementation options. Pays special attention to techniques for transforming between XML and HTML formats for rendering in today’s commercial Web browsers.