IEEE VIS Publication Dataset

Spherical color maps can be an effective tool in the microstructure visualization of polycrystals. Electron backscatter diffraction pattern analysis provides large arrays of the orientation data that can be visualized easily using the technique described in this paper. A combination of this technique with the traditional black and white scanning electron microscopy imaging will enable scientists to better understand the correlation between material properties and their polycrystalline structure

The paper describes three alternative volume rendering approaches to visualizing computational fluid dynamics (CFD) data. One new approach uses realistic volumetric gas rendering techniques to produce photo-realistic images and animations from scalar CFD data. The second uses ray casting that is based an a sampler illumination model and is mainly centered around a versatile new tool for the design of transfer functions. The third method employs a simple illumination model and rapid rendering mechanisms to provide efficient preview capabilities. These tools provide a large range of volume rendering capabilities to be used by the CFD explorer to render rapidly for navigation through the data, to emphasize data features (e.g., shock waves) with a specific transfer function, or to present a realistic rendition of the model

We describe how techniques from computer graphics are used to visualize pool fire data and compute radiative effects from pool fires. The basic tools are ray casting and accurate line integration using the RADCAL program. Example images in the visible and infrared band are shown which are given of irradiation calculations and novel methods to visualize the results of irradiation calculations

VolVis is a diversified, easy to use, extensible, high performance, and portable volume visualization system for scientists and engineers as well as for visualization developers and researchers. VolVis accepts as input 3D scalar volumetric data as well as 3D volume-sampled and classical geometric models. Interaction with the data is controlled by a variety of 3D input devices in an input device-independent environment. VolVis output includes navigation preview, static images, and animation sequences. A variety of volume rendering algorithms are supported ranging from fast rough approximations, to compression-domain rendering, to accurate volumetric ray tracing and radiosity, and irregular grid rendering

A new algorithm for identifying vortices in complex flows is presented. The scheme uses both the vorticity and pressure fields. A skeleton line along the center of a vortex is produced by a two-step predictor-corrector scheme. The technique uses the vector field to move in the direction of the skeleton line and the scalar field to correct the location in the plane perpendicular to the skeleton line. With an economical description of the vortex tube's cross-section, the skeleton compresses the representation of the flow by a factor of 4000 or more. We show how the reconstructed geometry of vortex tubes can be enhanced to help visualize helical motion

This paper presents a technique for performing volume morphing between two volumetric datasets in the wavelet domain. The idea is to decompose the volumetric datasets into a set of frequency bands, apply smooth interpolation to each band, and reconstruct to form the morphed model. In addition, a technique for establishing a suitable correspondence among object voxels is presented. The combination of these two techniques results in a smooth transition between the two datasets and produces morphed volume with fewer high frequency distortions than those obtained from spatial domain volume morphing

Much of the attention in visualization research has focussed on data rooted in physical phenomena, which is generally limited to three or four dimensions. However, many sources of data do not share this dimensional restriction. A critical problem in the analysis of such data is providing researchers with tools to gain insights into characteristics of the data, such as anomalies and patterns. Several visualization methods have been developed to address this problem, and each has its strengths and weaknesses. This paper describes a system named XmdvTool which integrates several of the most common methods for projecting multivariate data onto a two-dimensional screen. This integration allows users to explore their data in a variety of formats with ease. A view enhancement mechanism called an N-dimensional brush is also described. The brush allows users to gain insights into spatial relationships over N dimensions by highlighting data which falls within a user-specified subspace

We show how to create 3D models of maternal pelvis and fetal head from magnetic resonance images (MRI). The models are used to simulate the progress of delivery in order to give a prognosis of successful labor

A supercomputing-visualization facility for science and engineering applications was used for processing and visualizing supercomputer-generated data. This facility includes a vector-processing supercomputer, a graphics workstation, a general purpose workstation, a high-resolution color printer, a scanner, a film recorder, a video tape recorder, and a video laser disc recorder. The facility is using a network system to connect computers, workstations, and graphical input/output devices. The supercomputer generates time-dependent multivariate data using a global climate simulation model. Visualization software systems are used for visualizing these model-produced data. Visualization techniques including: iso-contouring, iso-surface generation, vectors and streamlines generation are used

A probe for the interactive visualization of flow fields is presented. The probe can be used to visualize many characteristics of the flow in detail for a small region in the data set. The velocity and the local change of velocity (the velocity gradient tensor) are visualized by a set of geometric primitives. To this end, the velocity gradient tensor is transformed to a local coordinate frame, and decomposed into components parallel with and perpendicular to the flow. These components are visualized as geometric objects with an intuitively meaningful interpretation. An implementation is presented which shows that this probe is a useful tool for flow visualization

In this work we present a method for speeding the process of volume animation. It exploits coherency between consecutive images to shorten the path rays take through the volume. Rays are provided with the information needed to leap over the empty space and commence volume traversal at the vicinity of meaningful data. The algorithm starts by projecting the volume onto a C-buffer (coordinates-buffer) which stores the object-space coordinates of the first non-empty voxel visible from a pixel. Following a change in the viewing parameters, the C-buffer is transformed accordingly. Next, coordinates that possibly became hidden are discarded. The remaining values serve as an estimate of the point where the new rays should start their volume traversal. This method does not require 3-D preprocessing and does not suffer from any image degradation. It can be combined with existing acceleration techniques and can support any ray traversal algorithm and material modeling scheme

In Rogowitz and Treinish (1993), we introduced an architecture for incorporating perceptual rules into the visualization process. In this architecture, higher-level descriptors of the data, metadata, flow to perceptual rules, which constrain visualization operations. In this paper, we develop a deeper analysis of the rules, the prerequisite metadata, and the system for enabling their operation

This paper presents an environment for telecollaborative data exploration. It provides the following capabilities essential to data exploration: (1) users can probe the data, defining regions of interest with arbitrary shapes. (2) The selected data can be transformed and displayed in many different ways. (3) Linked cursors can be established between several windows showing data sets with arbitrary relationships. (4) Data can be displayed on any screen across a computer network, allowing for telecollaboration arrangements with linked cursors around the world. (5) Our system is user-extensible, allowing programmers to change any component of it while keeping the remaining functionality. We demonstrate how the system can be used in several applications, such as biomedical imaging, robotics, and wood classification

Designers, implementers, and marketers of data analysis tools typically have different perspectives than end users. Consequently, data analysts often find themselves using tools focused on graphics and programming concepts rather than concepts which reflect their own domain and the context of their work. Some user studies focus on usability tests late in development; others observe work activity, but fail to show how to apply that knowledge in design. This paper describes a methodology for applying observations of data analysis work activity in prototype tool design. The approach can be used both in designing improved data analysis tools, and customizing visualization environments to specific applications. We present an example of user-centered design for a prototype tool to cull large data sets. We revisit the typical graphical approach of animating a large data set from the point of view of an analyst who is culling data. Field evaluations using the prototype tool not only revealed valuable usability information, but initiated in-depth discussions about user's work, tools, technology, and requirements

A prototype visualization management system is described which merges the capabilities of a database management system with any number of existing visualization packages such as AVS or IDL. The prototype uses the Postgres database management system to store and access Earth science data through a simple graphical browser. Data located in the database is visualized by automatically invoking a desired visualization package and downloading an appropriate script or program. The central idea underlying the system is that information on how to visualize a data set is stored in the database with the data set itself

The paper describes a highly interactive method for computer visualization of simultaneous three-dimensional vector and scalar flow fields in convection-diffusion systems. This method allows a computational fluid dynamics user to visualize the basic physical process of dispersion and mixing rather than just the vector and scalar values computed by the simulation. It is based on transforming the vector field from a traditionally Eulerian reference frame into a Lagrangian reference frame. Fluid elements are traced through the vector field for the mean path as well as the statistical dispersion of the fluid elements about the mean position by using added scalar information about the root mean square value of the vector field and its Lagrangian time scale. In this way, clouds of fluid elements are traced not just mean paths. We have used this method to visualize the simulation of an industrial incinerator to help identify mechanisms for poor mixing

Human beings find it difficult to analyze local and global oligonucleotide patterns in the linear primary sequences of a genome. In this paper, we present a family of iterated function systems (IFS) that can be used to generate a set of visual models of a DNA sequence. A new visualization function, the W-curve, that is derived from this IFS family is introduced. Using W-curves, a user can readily compare subsequences within a long genomic sequence - or between genomic sequences - and can visually evaluate the effect of local variations (mutations) upon the global genomic information content

The process of visualizing a scientific data set requires an extensive knowledge of the domain in which the data set is created. Because an in-depth knowledge of all scientific domains is not available to the creator of visualization software, a flexible and extensible visualization system is essential in providing a productive tool to the scientist. This paper presents a shading language, based on the RenderMan shading language, that extends the shading model used to render volume data sets. Data shaders, written in this shading language, give the users of a volume rendering system a means of specifying how a volume data set is to be rendered. This flexibility is useful both as a visualization tool in the scientific community and as a research tool in the visualization community

Modular application builders (MABs), such as AVS and Iris Explorer are increasingly being used in the visualization community. Such systems can already place compute intensive modules on supercomputers in order to utilize their power. This paper details two major projects at EPCC which attempted to fully integrate the MAB concept with a distributed memory MIMD (DM-MIMD) environment. The work presented was driven by two goals, efficient use of the resource and case of use by programmer and end user. We present a model of MABs and describe the major problems faced, giving solutions to them through two case studies

New display technologies have begun to provide more innovative and potentially powerful methods to present information to a viewer. However, many of these techniques struggle to deliver accurate full color. In this paper, we address this difficulty by employing the dichromatic theory of color reflection, which implies that many objects can be rendered accurately using only two primaries. Complex display systems with two primaries can be produced with significantly less work than is required for the traditional three primaries. We discuss methods for selecting objects that can be rendered accurately on two-color displays, and we present our experiments with a two-color display using monochromatic primaries