Abstract: Visual data mining techniques have proven to be of high value in exploratory data analysis, and they also have a high potential for mining large databases. In this article, we describe and evaluate a new visualization-based approach to mining large databases. The basic idea of our visual data mining techniques is to represent as many data items as possible on the screen at the same time by mapping each data value to a pixel of the screen and arranging the pixels adequately. The major goal of this article is to evaluate our visual data mining techniques and to compare them to other well-known visualization techniques for multidimensional data: the parallel coordinate and stick-figure visualization techniques. For the evaluation of visual data mining techniques, the perception of data properties counts most, while the CPU time and the number of secondary storage accesses are only of secondary importance. In addition to testing the visualization techniques using real data, we developed a testing environment for database visualizations similar to the benchmark approach used for comparing the performance of database systems. The testing environment allows the generation of test data sets with predefined data characteristics which are important for comparing the perceptual abilities of visual data mining techniques.

Abstract: Current user interfaces of full text retrieval systems do not help in the process of filtering the result of a query, usually very large. We address this problem and we propose a visual interface to handle the result of a query, based on a hybrid model for text. This graphical user interface provides several visual representations of the answer and its elements (queries, documents, and text), easing the analysis and the filtering process.

Abstract: : Visualization is often referred to as scientific visualization or visualization in scientific computing. Visualization helps us extract useful information from complex or often voluminous data sets through the use of interactive graphics and imaging. The theory of visualization uses foundations of the following fields and unifying them: Computer Graphics, Image processing, Computer Vision, Computer Aided Design, Signal processing, User Interface Studies, Cognitive Science, and Computational Geometry. The visualization technology was started with excitement and enthusiasm and gradually changed the scientific field for the past two decades. In this presentation we briefly review the following topics: Visualization - Some important points to note Visualization - Microarchitecture workbench Visualization - Medical field Visualization - Computer Generated Forces (CGF).

Abstract: In COVISE (COllaborative Visual Simulation Environemt) an interac­tive 3D renderer module has been embedded in order to fully support collaborative visualization for scientific computing in a distributed high performance environment. The visualization aspects of COVISE with respect to bandwidth needs and synchronization issues are presented. Typical user scenarios and recent performance measurement results of collaborative sessions with different machine architectures and network technologies are discussed.

Abstract: he global information infrastructure (Glii) T launched by Vice President A1 Gore sparked the public imagination and caused a burst of activity in R&D and commercial implementation of relevant technologies. Although involved with visualizing scientific data and generating realistic graphics, the computer graphics and visualization communities have not, in general, moved into the challenging world of information technology and the GII. We feel strongly that the GI1 must use the abilities and developments these communities have to offer to successfully reach people from all walks of life. The original impetus for this special report came from a suggestion by Tom Kalil (Director to the National Nahiuin Gershon Mitre Corporation

Abstract: Information Visualization for Children: The User in Context Considering the interior lives of children, from a design perspective it may be helpful to think about children as a series of cognitive communities, divided roughly along developmental stages. Piaget's four developmental stages are worth iterating, if only to phrase them in terms of children and computers, with the caveat that children are Art created at Chi Kids '96

Abstract: A new method for assisting with the visualization of large multidimensional datasets is proposed. We classify datasets with more than one million elements as large. Multidimensional data elements are elements with two or more dimensions, each of which is at least binary. Multidimensional data visualization involves representation of multidimensional data elements in a low dimensional environment, such as a computer screen or printed media. Traditional visualization techniques are not well suited to solving this problem. Our data visualization techniques are based in large part on a field of cognitive psychology called preattentive processing. Preattentive processing is the study of visual features that are detected rapidly and with little effort by the human visual system. Examples include hue, orientation, form, intensity, and motion. We studied ways of extending and applying research results from preattentive processing to address our visualization requirements. We used our investigations to build visualization tools that allow a user to very rapidly and accurately perform exploratory analysis tasks. These tasks include searching for target elements, identifying boundaries between groups of common elements, and estimating the number of elements that have a specific visual feature. Our experimental results were positive, suggesting that dynamic sequences of frames can be used to explore large amounts of data in a relatively short period of time. Recent work in both scientific visualization and database systems has started to address the problems inherent in managing large scientific datasets. One promising technique is knowledge discovery, "the nontrivial extraction of implicit, previously unknown, and potentially useful information from data". We hypothesise that knowledge discovery can be used as a filter to reduce the amount of data sent to the visualization tool. Data elements that do not belong to a user-chosen group of interest can be discarded, the dimensionality of individual data elements can be compressed, and previously unknown trends and relationships can be discovered and explored. We illustrate how our techniques can be used by applying them to real-world data and tasks. This includes the visualization of simulated salmon migration results, computerized tomography medical slices, and environmental datasets that track ocean and atmospheric conditions.

Abstract: Many educators have used Algorithm Visualization (AV) to teach students of computer science about how computer algorithms work. Our study sheds light on two important questions: (a) How do people conceptualize algorithm animations in the first place; and (b) To what extent do such visualizations accord with AV software. In the first half of this study, pairs of graduate students in computer science were asked to construct animations for a simple sort (bubble sort) using ordinary art materials. In the second half, they implemented a bubble sort visualization using an interactive AV program called LENS [1], which allows one to construct and view an animation of any C program. The way in which pairs visualized the same sort differed tremendously from each other and did not accord completely with the animation language provided by LENS. This paper analyzes those differences by a detailed examination of the semantics of the human visualizations, the algorithm code, and the LENS AV language.

Abstract: Distributed computing provides unique benefits for scientific visualization in this system (Discover) that supports interactive visualization and cooperative work for nonprogrammers. Discover (Distributed Interactive Scientific Computing and Visualization Environment), is suitable for many areas, but we have concentrated on medical image analysis and generation-one of the the most rapidly growing applications for scientific visualization. In its present form, Discover acts as a framework for clinical applications. True to its name, it allows a variety of users to discover the relevant information in a vast body of scientific data. Nonprogrammers, such as physicians and radiologists, interactively display and manipulate the two and three dimensional medical objects, visualize the results, control system computation, and generally drive the image analysis process. The emphasis is on the distributed nature of the software architecture and its functions. We also describe a unique load balancing algorithm designed to maximize workstation performance.

Abstract: Visualization is attracting more and more attention in a variety of disciplines including the domains of geographic informtion systems and cartography, since the US National Science Foundation work...

Abstract: In this paper we develop a performance model for analyzing the end-to-end lag in a combined supercomputer/virtual environment. We first present a general model and then use this model to analyze the lag of an interactive, immersive visualization of a scientific application. This application consists of a finite element simulation executed on an IBM SP-2 parallel supercomputer and the results displayed in real-time in the CAVE Automatic Virtual Environment. Our model decouples the viewpoint lag (not involving the simulation) from the interaction lag (using the results of the simulations). This model allows one to understand the relative contributions to end-to-end lag of the following components: rendering, tracking, network latency, simulation time, and various types of synchronization lags. The results of the study indicate that the rendering and network latency are the major contributors of the end-to-end lag.

Abstract: Interactive metric visualization is a novel approach providing complex, multi-dimensional feedback on the effects of layout changes in user interface designs. A graphical overlay based on the underlying rationale of quantitative design metrics, provides immediate feedback, continually guiding designers toward improved layouts. Effective visual metaphors, colour coding, and dynamic updating enable designers to interpret and utilize more complex information than from simple quantitative data or static overlays. This technique is especially suited to accelerated design and development using modern visual development tools. An experimental prototype for this approach is described and initial experience is reported.

Abstract: As a powerful technique for the visual representation of complex data, scientific visualization offers the potential to help secondary school science students learn through active inquiry. Over a period of several years, we have been conducting research in the design of scientific visualization environments that support inquiry-based learning. The goal is to support students in a multi-stage learning process that culminates in open-ended research projects. In the early stages, learners should gain familiarity with scientific visualization techniques and the phenomena depicted. In the later stages, students conduct investigations that use scientific visualization techniques to explore open-ended questions. Through the process of conducting inquiry with scientific visualization students can gain an understanding of its usefulness for originating and answering scientific questions.

Abstract: Dynamic queries constitute a very powerful mechanism for information visualization; some universe of data is visualized, and this visualization is modified on-the-fly as users modify the range of interest within the domains of the various attributes of the visualized information. In this paper, we analyze dynamic queries and offer some natural generalizations of the original concept by establishing a connection to SQL. We also discuss some implementation ideas that should make these generalizations efficient as well.

Abstract: Visual interfaces to computer systems are interactive. The cycle of visual interaction involves both visual perception and action. This paper examines formal models of interactive systems and cognitive models of users. Neither completely captures the special nature of visual interaction. In order to investigate this, the paper examines two forms of non-visual interaction: mathematics for the blind and interaction by smell (nasal interaction). Finally three forms of more pragmatic design-oriented method are considered: information rich task analysis (what information is required), status-event analysis (when it is perceived) and models of information (how to visually interact with it).

Abstract: 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.

Abstract: Information visualizations must allow users to browse information spaces and focus quickly on items of interest. Being able to see some representation of the entire information space provides an initial gestalt overview and gives context to support browsing and search tasks. However, the limited number of pixels on the screen constrain the information bandwidth and make it di cult to completely display large information spaces. The Information Mural is a two-dimensional, reduced representation of an entire information space that ts entirely within a display window or screen. The mural creates a miniature version of the information space using visual attributes such as grayscale shading, intensity, color, and pixel size, along with anti-aliased compression techniques. Information Murals can be used as stand-alone visualizations or in global navigational views. We have built several prototypes to demonstrate the use of Information Murals in visualization applications; subject matter for these views includes computer software, scienti c data, text documents, and geographic information.

Abstract: Visualization techniques provide valuable tools for interpreting the huge amount of data being generated by new detection devices and simulation algorithms. Their effectiveness is limited among other reasons, by the lack of a comprehensive approach towards considering human needs and exploring their abilities. This paper proposes a system and a model for integrating visualization and imaging techniques in order to study and implement strategies to enhance data and phenomena interpretation. This system (PowerVis) aims at providing new forms of graphical and auditory mappings that improve conventional approaches to visualization systems.

Abstract: This paper describes an `interaction interface' for visual database exploration. Visualization has been traditionally thought of as an output technology: this research places visualization into a broader context and aims to develop an input model for the visual exploration of databases. We first describe the data infrastructure of an integrated database-visualization system. We then extend the definition of visualization to include the data interactions allowed over the visualized image. We finally present the portion of this system that describes how interactions over data visualizations are mapped to the targets of the visual interaction: the various data objects in the system, or the database itself. In this way, the user is brought closer to the data because interaction is over a visualization, which is perceived by the user, and the correct effect of the interaction is automatically mapped to the appropriate underlying data object. We build on a fundamental taxonomy of empirically-developed data interaction, and use these interaction specifications in our object-oriented design.

Abstract: Many now recognize that mining for information and knowledge from large databases and documents will be the next fundamental impact in database systems, knowledge discovery, and visualization. This is considered an important area for major cost savings and potential revenue, and it has immediate applications in decision systems, intelligence, information management, business, and communication in the form of both on-line services and the World Wide Web. Data mining now draws from fields including databases, statistics, information technology. data visualization, and artificial intelligence, especially machine learning and knowledge-based systems. There is a clear sense that, to achieve the next increase in knowledge exploitation, individual data exploration approaches must work together.

Abstract: Visual reasoning is an essential skill for an engineer to possess, particularly as computer-aided design tools become more prevalent. We describe an innovative multimedia application that provides a student with the tools to build a strong foundation in visual reasoning. The system, called the Visual Reasoning Tutor, exploits the missing view problem as a mechanism to develop the visual reasoning abilities of students, and utilizes multimedia capabilities to enhance the learning process. The Visual Reasoning Tutor provides a student with interactive, geometric operations and intelligent critiques at varying levels of help throughout the steps of a student's solution.

Abstract: In the course of global change studies, a scientist would often like to efficiently store, retrieve, analyze and interpret selected data sets from a large collection of scientific information scattered across heterogeneous computational environments, Earth observing system data repositories, and to share the gleaned information with other scientific communities. To facilitate the above activities, we have developed OASIS, a flexible, extensible, and seamless environment for scientific data analysis, knowledge discovery, visualization, and collaboration.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Abstract: Our MultiMedia Visual Information Seeking (MMVIS) environment is designed to support an exploratory approach to video analysis. Specialized subset, temporal, spatial, and motion dynamic query filters are tightly coupled with dynamic, user-customizable relationship visualizations to aid users in the discovery of data trends. Users can select two subsets (e.g., a subset of person PI talking events) and then browse various relationships between them (e.g., browsing for temporal relationships such as whether events of type A frequently start at the same time as events of type B), The visualization highlights the frequencies of both the subsets and the relationships between them. This allows users to discover various relationships and trends without having to explicitly pre-code them. In this demonstration, we will focus on temporal analysis aspects of the system, presenting our temporal visual query language, temporal visualization, and an application to real CSCW data.

Abstract: 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.

Abstract: Programming concepts - programming is a real world activity programming in the large concepts of visual programming program visualization tools for visualization programming in a VR setting. Visual metaphors and the problem of perception - perception, cognition, visualization and interactive use of databases scientific visualization and analytical models the concepts of Realspace World Wide Web HTML and VRML Java.