IEEE VIS Publication Dataset

In recent years scientific visualization has been driven by the need to visualize high-dimensional data sets within high-dimensional spaces. However most visualization methods are designed to show only some statistical features of the data set. The paper deals with the visualization of trajectories of high-dimensional dynamical systems which form a L n n data set of a smooth n-dimensional flow. Three methods that are based on the idea of parallel coordinates are presented and discussed. Visualizations done with these new methods are shown and an interactive visualization tool for the exploration of high-dimensional dynamical systems is proposed.

VizWiz is a Java applet that provides basic interactive scientific visualization functionality, such as isosurfaces, cutting planes, and elevation plots, for 2D and 3D datasets that can be loaded into the applet by the user via, the applet's Web server. VizWiz is unique in that it is a completely platform independent scientific visualization tool, and is usable over the Web, without being manually downloaded or installed. Its 3D graphics are implemented using only the Java AWT API, making them portable across all Java supporting platforms. The paper describes the implementation of VizWiz, including design tradeoffs. Graphics performance figures are provided for a number of different platforms. A solution to the problem of uploading user data files into a Java applet, working around security limitations, is demonstrated. The lessons learned from this project are discussed.

One well known application area of volume rendering is the reconstruction and visualization of output from medical scanners like computed tomography (CT). 2D greyscale slices produced by these scanners can be reconstructed and displayed onscreen as a 3D model. Volume visualization of medical images must address two important issues. First, it is difficult to segment medical scans into individual materials based only on intensity values. Second, although greyscale images are the normal method for displaying medical volumes, these types of images are not necessarily appropriate for highlighting regions of interest within the volume. Studies of the human visual system have shown that individual intensity values are difficult to detect in a greyscale image. In these situations colour is a more effective visual feature. We addressed both problems during the visualization of CT scans of abdominal aortic aneurysms. We have developed a classification method that empirically segments regions of interest in each of the 2D slices. We use a perceptual colour selection technique to identify each region of interest in both the 2D slices and the 3D reconstructed volumes. The result is a colourized volume that the radiologists are using to rapidly and accurately identify the locations and spatial interactions of different materials from their scans. Our technique is being used in an experimental post operative environment to help to evaluate the results of surgery designed to prevent the rupture of the aneurysm. In the future, we hope to use the technique during the planning of placement of support grafts prior to the actual operation.

An eigenvector method for vortex identification has been applied to recent numerical and experimental studies in external flow aerodynamics. It is shown to be an effective way to extract and visualize features such as vortex cores, spiral vortex breakdowns, vortex bursting, and vortex diffusion. Several problems are reported and illustrated. These include: disjointed line segments, detecting non-vortical flow features, and vortex core displacement. Future research and applications are discussed, such as using vortex cores to guide automatic grid refinement.

The paper addresses multiresolutional representation of datasets arising from a computational field simulation. The approach determines the regions of interest, breaks the volume into variable size blocks to localize the information, and then codes each block using a wavelet transform. The blocks are then ranked by visual information content so that the most informative wavelet coefficients can be embedded in a bit stream for progressive transmission or access. The technique is demonstrated on a widely-used computational field simulation dataset.

Many techniques have been developed for visualizing multivariate (multidimensional) data. Most, if not all, are limited by the number of dimensions which can be effectively displayed. Multidimensional scaling (MDS) is an iterative non-linear technique for projecting n-D data down to a lower number of dimensions. This work presents extensions to MDS that enhance visualization of high-dimensional data sets. These extensions include animation, stochastic perturbation, and flow visualization techniques

Automated graphical generation systems should be able to design effective presentations for heterogeneous (quantitative and qualitative) information in static or interactive environments. When building such a system, it is important to thoroughly understand the presentation-related characteristics of domain-specific information. We define a data-analysis taxonomy that can be used to characterize heterogeneous information. In addition to capturing the presentation-related properties of data, our characterization takes into account the user's information-seeking goals and visual-interpretation preferences. We use automatically-generated examples from two different application domains to demonstrate the coverage of the proposed taxonomy and its utility for selecting effective graphical techniques

HNC Software, Inc. has developed a system called DEPICT for visualizing the information content of large textual corpora. The system is built around two separate neural network methodologies: context vectors and self-organizing maps. Context vectors (CVs) are high dimensional information representations that encode the semantic content of the textual entities they represent. Self-organizing maps (SOMs) are capable of transforming an input, high dimensional signal space into a much lower (usually two or three) dimensional output space useful for visualization. Neither process requires human intervention, nor an external knowledge base. Together, these neural network techniques can be utilized to automatically identify the relevant information themes present in a corpus, and present those themes to the user in a intuitive visual form

As the use of 3D information presentation becomes more prevalent, the need for effective viewing tools grows accordingly. Much work has been done in developing tools for 2D spaces which allow for detail in context views. We examine the extension of such 2D methods to 3D and explore the limitations encountered in accessing internal regions of the data with these methods. We then describe a novel solution to this problem of internal access with the introduction of a distortion function which creates a clear line of sight to the focus revealing sections previously obscured. The distortion is symmetric about the line of sight and is smoothly integrated back into the original 3D layout.

We present a new multiresolution visualization design which allows a user to control the physical data resolution as well as the logical display resolution of multivariate data. A system prototype is described which uses the HyperSlice representation. The notion of space projection in multivariate data is introduced. This process is coupled with wavelets to form a powerful tool for very large data visualization

We outline a spreadsheet-based system for visualization of real-time financial information. Our system permits the user to define arithmetic and presentation relationships amongst the various cells of the spreadsheet. The cells contain primitives that can be numbers, text, images, functions and graphics. Presenting financial information in this format allows its intended clients, the financial analysts, to work in the familiar environment of a spreadsheet and allows them the flexibility afforded by the powerful interface of the spreadsheet paradigm. In addition, our system permits real-time visualization of the financial data stream allowing its user to visually trade the changing market trends in two and three dimensions

This paper presents the query and visualization interfaces of the Master Environmental Library (MEL) system. MEL uses the World Wide Web (WWW) to make accessible distributed data whose metadata conform to the Federal Geographic Data Committee's (FGDC) content standards for digital geospatial metadata. The interfaces are implemented as JavaTM applets and are more intuitive, interactive and possess greater functionality than their Hypertext Markup Language (HTML) counterparts. As well as querying, the interface allows users to visualize and manage the list of query results so that users can more quickly discover the datasets of real interest. Several new tools used to visualize attributes of the metadata are presented.

Many business data visualization applications involve large databases with dozens of fields and millions of rows. Interactive visualization of these databases is difficult because of the large amount of data involved. We present a method of summarizing large databases which is well suited to interactive visualization. We illustrate this with a visualization tool for the domain of call billing data

This paper describes a minimally immersive volumetric interactive system for information visualization. The system, SFA, uses glyph-based volume rendering, enabling more information attributes to be visualized than traditional 2D and surface-based information visualization systems. Two-handed interaction and stereoscopic viewing combine to produce a minimally immersive interactive system that enhances the user's three-dimensional perception of the information space, capitalizing on the human visual system's pre-attentive learning capabilities to quickly analyze the displayed information. The paper describes the usefulness of this system for the visualization of document similarity within a corpus of textual documents. SFA allows the three-dimensional volumetric visualization, manipulation, navigation, and analysis of multivariate, time-varying information spaces, increasing the quantity and clarity of information conveyed from the visualization as compared to traditional 2D information systems

Interactive techniques are powerful tools for manipulating visualizations to analyze, communicate and acquire information. This is especially true for large data sets or complex 3D visualizations. Although many new types of interaction have been introduced recently, very little work has been done on understanding what their components are, how they are related and how they can be combined. This paper begins to address these issues with a framework for classifying interactive visualizations. Our goal is a framework that will enable us to develop toolkits for assembling visualization interfaces both interactively and automatically

Discusses a software tool called VANISH (Visualizing And Navigating Information Structured Hierarchically), which supports the rapid prototyping of interactive 2D and 3D information visualizations. VANISH supports rapid prototyping through a special-purpose visual language called VaPL (VANISH Programming Language) tailored for visualizations, through a software architecture that insulates visualization-specific code from changes in both the domain being visualized and the presentation toolkit used, and through the reuse of visualization techniques between application domains. The generality of VANISH is established by showing how it is able to re-create a wide variety of ÔÇ£standardÔÇØ visualization techniques. VANISH's support for prototyping is shown through an extended example, where we build a C++ class browser, exploring many visualization alternatives in the process

Visualization is a critical technology for understanding complex, data-rich systems. Effective visualizations make important features of the data immediately recognizable and enable the user to discover interesting and useful results by highlighting patterns. A key element of such systems is the ability to interact with displays of data by selecting a subset for further investigation. This operation is needed for use in linked-views systems and in drill-down analysis. It is a common manipulation in many other systems. It is as ubiquitous as selecting icons in a desktop GUI. It is therefore surprising to note that little research has been done on how selection can be implemented. This paper addresses this omission, presenting a taxonomy for selection mechanisms and discussing the interactions between branches of the taxonomy. Our suggestion of 524,288 possible systems [216 operation systems×2 (memory/memoryless)×2 (data-dependent/independent)×2 (brush/lasso)] is more in fun than serious, as within the taxonomy there are many different choices that can be made. This framework is the result of considering both the current state of the art and historical antecedents

This paper presents efficient methods for implementing general non-linear magnification transformations. Techniques are provided for: combining linear and non-linear magnifications, constraining the domain of magnifications, combining multiple transformations, and smoothly interpolating between magnified and normal views. In addition, piecewise linear methods are introduced which allow greater efficiency and expressiveness than their continuous counterparts

The Harmony browser for the Hyper-G Web server utilises Hyper-G's rich data model to provide a number of tightly-coupled, two- and three-dimensional visualisation and navigational facilities. In particular the Harmony Information Landscape visualises the hierarchical structure of Hyper-G spaces upon a plane in three-dimensional space. The Harmony Information Landscape has now been extended to display a combined structure and link map by selectively superimposing hyperlink relationships in the vertical dimension above and below the hierarchy map. In addition, documents returned by search queries may be selectively ÔÇ£plottedÔÇØ in the landscape, indicating their whereabouts in a broader context, and several sets of 3D icons are available for representing the various document types

Visage is a prototype user interface environment for exploring and analyzing information. It represents an approach to coordinating multiple visualizations, analysis and presentation tools in data-intensive domains. Visage is based on an information-centric approach to user interface design which strives to eliminate impediments to direct user access to information objects across applications and visualizations. Visage consists of a set of data manipulation operations, an intelligent system for generating a wide variety of data visualizations (SAGE) and a briefing tool that supports the conversion of visual displays used during exploration into interactive presentation slides. This paper presents the user interface components and styles of interaction that are central to Visage's information-centric approach