Service-oriented architectures are increasingly being used as the architectural style for creating large distributed computer applications. This paper examines the provision of visualization as a service that can be made available to application designers in order to combine with other services. We develop a three-layer architecture: a client layer which provides the user interface; a stateful Web service middleware layer which provides a published interface to the visualization system; and finally, a visualization component layer which provides the core functionality of visualization techniques. This separation of middleware from the visualization components is crucial: it allows us to exploit the strengths of Web service technologies in providing standardized access to the system, and in maintaining state information throughout a session, but also gives us the freedom to build our visualization layer in an efficient and flexible way without the constraints of Web service protocols. We describe the design of a visualization service based on this architecture, and illustrate one aspect of the work by re-visiting an early example of Web-based visualization.

Abstract This paper presents a new service‐oriented approach to the design and implementation of visualization systems in a Grid computing environment. The approach evolves the traditional dataflow visualization system, based on processes communicating via shared memory or sockets, into an environment in which visualization Web services can be linked in a pipeline using the subscription and notification services available in Globus Toolkit 4. A specific aim of our design is to support collaborative visualization, allowing a geographically distributed research team to work collaboratively on visual analysis of data. A key feature of the system is the use of a formal description of the visualization pipeline, using the skML language first developed in the gViz e‐Science project. This description is shared by all collaborators in a session. In co‐operation with the e‐Viz project, we generate user interfaces for the visualization services automatically from the skML description. The new system is called notification‐service‐based collaborative visualization. A simple prototype has been built and is used to illustrate the concepts. Copyright © 2008 John Wiley & Sons, Ltd.

In standard analysis of cardiac models, typically one variable - usually the trans-membrane potential - is used in the generation of visualizations. However, all but the most basic models have many state variables at each node, information that is not used when visualizing the output of the model. In this paper, we present a novel approach to visualizing the entire state of a 2D cardiac virtual tissue

Abstract The medical domain provides excellent opportunities for the application of computer graphics, visualization and virtual environments, with the potential to help improve healthcare and bring benefits to patients. This survey paper provides a comprehensive overview of the state‐of‐the‐art in this exciting field. It has been written from the perspective of both computer scientists and practising clinicians and documents past and current successes together with the challenges that lie ahead. The article begins with a description of the software algorithms and techniques that allow visualization of and interaction with medical data. Example applications from research projects and commercially available products are listed, including educational tools; diagnostic aids; virtual endoscopy; planning aids; guidance aids; skills training; computer augmented reality and use of high performance computing. The final section of the paper summarizes the current issues and looks ahead to future developments.

Abstract This paper discusses the problem of visualizing data where there are underlying constraints that must be preserved. For example, we may know that the data are inherently positive. We show how the Modified Quadratic Shepard method, which interpolates scattered data of any dimensionality, can be constrained to preserve positivity. We do this by forcing the quadratic basis functions to be positive. The method can be extended to handle other types of constraints, including lower bound of 0 and upper bound of 1—as occurs with fractional data. A further extension allows general range restrictions, creating an interpolant that lies between any two specified functions as the lower and upper bounds.

Abstract If we were to have a Grid infrastructure for visualization, what technologies would be needed to build such an infrastructure, what kind of applications would benefit from it, and what challenges are we facing in order to accomplish this goal? In this survey paper, we make use of the term ‘visual supercomputing’ to encapsulate a subject domain concerning the infrastructural technology for visualization. We consider a broad range of scientific and technological advances in computer graphics and visualization, which are relevant to visual supercomputing. We identify the state‐of‐the‐art technologies that have prepared us for building such an infrastructure. We examine a collection of applications that would benefit enormously from such an infrastructure, and discuss their technical requirements. We propose a set of challenges that may guide our strategic efforts in the coming years.

Grid computing provides a challenge for visualization system designers. In this research, we evolve the dataflow concept to allow parts of the visualization process to be executed remotely in a secure and seamless manner. We see dataflow at three levels: an abstract specification of the intent of the visualization; a binding of these abstract modules to a specific software system; and then a binding of software to processing and other resources. We develop an XML application capable of describing visualization at the three levels. To complement this, we have implemented an extension to a popular visualization system, IRIS Explorer, which allows modules in a dataflow pipeline to run on a set of grid resources. For computational steering applications, we have developed a library that allows a visualization system front-end to connect to a simulation running remotely on a grid resource. We demonstrate the work in two applications: the dispersion of a pollutant under different wind conditions; and the solution of a challenging numerical problem in elastohydrodynamic lubrication.

Recent activity within the UK National e-Science Programme has identified a need to establish an ontology for visualization. Motivation for this includes defining web and grid services for visualization (the ‘semantic grid’), supporting collaborative work, curation, and underpinning visualization research and education. At a preliminary meeting, members of the UK visualization community identified a skeleton for the ontology. We have started to build on this by identifying how existing work might be related and utilized. We believe that the greatest challenge is reaching a consensus within the visualization community itself. This poster is intended as one step in this process, setting out the perceived needs for the ontology, and sketching initial directions. It is hoped that this will lead to debate, feedback and involvement across the community.

Abstract Visualization is a powerful tool for analyzing data and presenting results in science, engineering and medicine. This paper reviews ways in which it can be used in distributed and/or collaborative environments. Distributed visualization addresses a number of resource allocation problems, including the location of processing close to data for the minimization of data traffic. The advent of the Grid Computing paradigm and the link to Web Services provides fresh challenges and opportunities for distributed visualization—including the close coupling of simulations and visualizations in a steering environment. Recent developments in collaboration have seen the growth of specialized facilities (such as Access Grid) which have supplemented traditional desktop video conferencing using the Internet and multicast communications. Collaboration allows multiple users—possibly at remote sites—to take part in the visualization process at levels which range from the viewing of images to the shared control of the visualization methods. In this review, we present a model framework for distributed and collaborative visualization and assess a selection of visualization systems and frameworks for their use in a distributed or collaborative environment. We also discuss some examples of enabling technology and review recent work from research projects in this field.

Abstract Soft object modelling is crucial in providing realistic simulation of many surgical procedures. High accuracy is achievable using the Finite Element Method (FEM), but significant computational power is required. We are interested in providing Web‐based surgical training simulation where such computational power is not available, but in return lower accuracy is often sufficient. A useful alternative to FEM is the 3D ChainMail algorithm that models elements linked in a regular, rectangular mesh, mimicking the behaviour of chainmail armour. An important aspect is the ability to make topology changes for example by cutting — an aspect that FEM finds difficult. Our contribution is to extend the 3D ChainMail technique to arbitrary grids in 2D and 3D. This extends the range of applications that can be addressed by the ChainMail approach, to include surfaces and volumes defined on triangular and tetrahedral meshes. We have successfully deployed the algorithm in a Web‐based environment, using VRML and Java linked through the External Authoring Interface. ACM CSS: I.3.5 Computer graphics: Computional Geometry and Object Modelling, I.3.2 Computer Graphics: Graphics Systems, J.3 Life and Medical Sciences

This paper proposes a modification of the Marching Cubes algorithm for isosurfacing, with the intent of improving the representation of the surface in the interior of each grid cell. Our objective is to create a representation which correctly models the topology of the trilinear interpolant within the cell and which is robust under perturbations of the data and threshold value. To achieve this, we identify a small number of key points in the cell interior that are critical to the surface definition. This allows us to efficiently represent the different topologies that can occur, including the possibility of "tunnels." The representation is robust in the sense that the surface is visually continuous as the data and threshold change in value. Each interior point lies on the isosurface. Finally, a major feature of our new approach is the systematic method of triangulating the polygon in the cell interior.

In the past few years, there have been key advances in the three main approaches to the visualization of volumetric data: isosurfacing, slicing and volume rendering, which together make up the field of volume visualization. In this survey paper we set the scene by describing the fundamental techniques for each of these approaches, using this to motivate the range of advances which have evolved over the past few years. In isosurfacing, we see how the original marching cubes algorithm has matured, with improvements in robustness, topological consistency, accuracy and performance. In the performance area, we look in detail at pre‐processing steps which help identify data which contributes to the particular isosurface required. In slicing too, there are performance gains from identifying active cells quickly. In volume rendering, we describe the two main approaches of ray casting and projection. Both approaches have evolved technically over the past decade, and the holy grail of real‐time volume rendering has arguably been reached. The aim of this review paper is to pull these developments together in a coherent review of recent advances in volume visualization.

Throughout the design cycle, visualization, whether a sketch scribbled on the back of a spare piece of paper or a fully detailed drawing, has been the mainstay of design: we need to see the product. One of the most important stages of the design cycle is the initial, or concept, stage and it is here that design variants occur in large numbers to be vetted quickly. At this initial stage the human element, the designer is crucial to the success of the product. We describe an interactive environment for concept design which recognises the needs of the designer, not only to see the product and make rapid modifications, but also to monitor the progress of their design towards some preferred solution. This leads to the notion of a design parameter space, typically high-dimensional, which must also be visualized in addition to the product itself. Using a module developed for IRIS Explorer design steering is presented as a navigation of this space in order to search for optimal designs, either manually or by local optimisation.

Current visualization systems are designed around a single user model, making it awkward for large research teams to collectively analyse large data sets. The paper shows how the popular data flow approach to visualization can be extended to allow multiple users to collaborate-each running their own visualization pipeline but with the opportunity to connect in data generated by a colleague, Thus collaborative visualizations are 'programmed' in exactly the same 'plug-and-play' style as is now customary for single-user mode. The paper describes a system architecture that can act as a basis for the collaborative extension of any data flow visualization system, and the ideas are demonstrated through a particular implementation in terms of IRIS Explorer.

article Free Access Share on An overview of visualization: its use and design: report of the working group in visualization Authors: Joe Bergin Pace University Pace UniversityView Profile , Ken Brodie University of Leeds, UK University of Leeds, UKView Profile , Marta Patiño-Martínez Universitat Politecnica de Madrid, Spain Universitat Politecnica de Madrid, SpainView Profile , Myles McNally Alma College Alma CollegeView Profile , Tom Naps Lawrence University Lawrence UniversityView Profile , Susan Rodger Duke University Duke UniversityView Profile , Judith Wilson Temple University Temple UniversityView Profile , Michael Goldweber Beloit College Beloit CollegeView Profile , Sami Khuri San Jose State University San Jose State UniversityView Profile , Ricardo Jiménez-Peris Universitat Politecnica de Madrid, Spain Universitat Politecnica de Madrid, SpainView Profile Authors Info & Claims ACM SIGCUE OutlookVolume 24Issue 1-3Jan.-July, 1996 pp 192–200https://doi.org/10.1145/1013718.237647Online:01 January 1996Publication History 30citation851DownloadsMetricsTotal Citations30Total Downloads851Last 12 Months41Last 6 weeks6 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my Alerts New Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

Scientific visualization is becoming an important part of the curriculum in a number of disciplines.It is a very practical subject, but the commercially available visualization software systems are not easy to learn.Thus we have explored the use of novel technology to help us in teaching students to use IRIS Explorer -this includes on-line tutorials, shared sessions involving teacher and student over a network, and the use of WWW. This work, which has been stimulated by teaching applications, has also motivated research into the wider area of collaborative visualization.

Explores the way in which data visualization systems, in particular modular visualization environments, can be used over the World Wide Web. The conventional approach is for the publisher of the data also to be responsible for creating the visualization, and posting it as an image on the Web. This leaves the viewer in a passive role, with no opportunity to analyse the data in any way. We look at different scenarios that occur as we transfer more responsibility for the creation of the visualization to the viewer, allowing visualization to be used for analysis as well as presentation. We have implemented one particular scenario, where the publisher mounts the raw data on the Web, and the viewer accesses this data through a modular visualization environment-in this case, IRIS Explorer. The visualization system is hosted by the publisher, but its fine control is the responsibility of the viewer. The picture is returned to the viewer as VRML, for exploration via a VRML viewer such as Webspace. We have applied this to air quality data which is posted on the Web hourly: through our system, the viewer selects what data to look at (e.g. species of pollutant, location, time period) and how to look at it-at any time and from anywhere on the Web.

Panel SummaryWho and what are standards for?Are standards there to protect users' investments and ease the design of working, integrated solutions or are they there to generate product opportunities for suppliers?Given enough confusion in the market place the effect is to turn standards into supplier's opportunity, at the expense of users' protection.Extensions, registrations, revisions, profiles, and levels of certification all conspire to confuse the situation.The pressure to adopt Publicly Available Specifications and the perceived advantages of "de facto" standards can undermine the protective intent of "de jure" standards.This panel debates different attitudes to standards, often associated with different sides of the Atlantic, but also between standardiser, politician, supplier and user.Concern over slow progress in ISO growing, but even concern is slow to take effect!Political pressure for change has never been stronger (for example at the recent CEC workshop on choosing standardisation policy -attended by 350+ delegates.Proposed methods of standardisation often assume that fasttracking PASs will produce a better result, more speedily, but ignore the lack of success of fast-tracking to date in the graphics area.Related topics for discussion include: 1) Is conformance certification worth the cost?2) Portability v Extensibility? 3) Upwards compatibility-how is/should existing investment in products be protected.4) Should registered items be allowed as a way of bypassing standards?5) How should profiling be used.6) De facto v de jure standardisation.7) Can/should fast-tracking PASs be made to work?

Visualization has proved an efficient tool in the understanding of large data sets in computational science and engineering. There is growing interest today in the development of problem solving environments which integrate both visualization and the computational process which generates the data. The GRASPARC project has looked at some of the issues involved in creating such an environment. An architecture is proposed in which tools for computation and visualization can be embedded in a framework which assists in the management of the problem solving process. This framework has an integral data management facility which allows an audit trail of the experiments to be recorded. This design therefore allows not only steering but also backtracking and more complicated problem solving strategies. A number of demonstrator case studies have been implemented.>

Conformance testing of graphics systems is a very complex and exhausting task. Years of practice with the GKS testing tools have shown a need for the automatic testing of visual output. Indeed, with regard to graphics systems which are more precisely specified than GKS like the Computer Graphics Interface (CGI), conformance testing is not manageable at all unless a major part can be automated. This paper discusses different strategies for the automatic testing of pictorial effect. It concentrates on the definition of lines and describes a strategy to answer the question put in the title by the testing system. Finally, automatic testing of simple graphical operations such as segment highlighting and visibility is discussed.

Summary The outcome of the Miltenberg meeting shows that a practical method of certification by testing (falsification) can be developed, given a reasonable amount of time and effort. It is based on semiautomatic comparison at the “device” interface of a candidate implementation against a so‐called reference implementation. A prerequisite for this method is the availability of a number of isolated simple basic facilities of the candidate implementation which have been verified by pictorial testing and by testing through operator actions. To permit semi‐automatic comparison, a format for describing graphical output and input items and their associated properties must be defined. The workshop produced an outline design for such a format, which can be applied at any interface within GKS at which testing might be desirable.