IEEE VIS Publication Dataset

An implementation of a virtual environment for visualizing the geometry of curved spacetime by the display of interactive geodesics is described. This technique displays the paths of particles under the influence of gravity as described by the general theory of relativity and is useful in the investigation of solutions to the field equations of that theory. A boom-mounted six-degree-of-freedom head-position-sensitive stereo CRT system is used for display. A hand-position-sensitive glove controller is used to control the initial positions and directions of geodesics in spacetime. A multiprocessor graphics workstation is used for computation and rendering. Several techniques for visualizing the geometry of spacetime using geodesics are discussed. Although this work is described exclusively in the context of physical four-dimensional spacetimes, it extends to arbitrary geometries in arbitrary dimensions. While this work is intended for researchers, it is also useful for the teaching of general relativity

VISAGE, a scientific visualization system implemented in an object-oriented, message passing environment, is described. The system includes over 500 classes ranging from visualization and graphics to Xlib and Motif user interface. Objects are created using compiled C and interact through an interpreted scripting language. The result is a flexible yet efficient system that has found wide application. The object architecture, the major issues faced when designing the visualization classes, and sample applications are also described

A visual interface for a multimedia database management system (MDBMS) is described. DBMS query languages are linear in syntax. Although natural language interfaces have been found to be useful, natural language is ambiguous and difficult to process. For queries on standard (relational) data, these difficulties can be avoided with the use of a visual, graphical interface to guide the user in specifying the query. For image and other media data which are ambiguous in nature, natural language processing, combined with direct graphical access to the domain knowledge, is used to interpret and evaluate the natural language query. The system fully supports graphical and image input/output in different formats. The combination of visual effect and natural language specification, the support of media data, and the allowance of incremental query specification simplify the process of query specification not only for image or multimedia databases but also for all databases

An information retrieval frame work that promotes graphical displays, and that will make documents in the computer visualizable to the searcher, is described. As examples of such graphical displays, two simulation results of using a Kohonen feature map to generate map displays for information retrieval are presented and discussed. The map displays are a mapping from a high-dimensional document space to a two-dimensional space. They show document relationships by various visual cues, such as dots, links, clusters, and areas, as well as their measurement and spatial arrangement. Using the map displays as an interface for document retrieval systems, the user is provided with richer visual information to support browsing and searching

A new way of reconstructing human fossils from fragmentary fossil material is described. Unlike the traditional method of making physical models using clay, this new approach is based on geometrical modeling and visualization of digitized fossil data. It can provide anthropologists with both quantifiable, computer-based geometric models and physical plastic reconstructions of fossils

Discusses the uses of visualization in the field of neuroscience is reported. The applications discussed are image analysis for basic neurobiological problems, image analysis from basic to applied neurobiological problems, management of images and graphics from anatomical experiments, and visualization and analysis of multivariate electrophysiological data sets

A project in the field of computational electrocardiography which requires visualization of complex, three-dimensional geometry and electric potential and current fields is described. Starting from magnetic resonance images (MRIs) from a healthy subject, a multisurfaced model of the human thorax was constructed and used as the basis for computational studies relating potential distributions measured from the surface of the heart to potentials and currents throughout the volume of the thorax (a form of the forward problem in electrocardiography). Both interactive and batch-mode graphics programs were developed to view, manipulate, and interactively edit the model geometry. Results are presented

Methods are presented for the visualization of fuzzy data based on the sensitivity of the human visual system to motion and dynamic changes, and the ease of which electronic display devices can change their display. The methods include taking an otherwise static image and displaying in an animation loop either its segmented components or a series of blurred versions of the whole image. This approach was applied to sea-surface temperature data and was found to be effective in showing fuzzy details embedded in the data, and in drawing the viewer's attention. This approach and these methods could play a significant role in the display of browse products for massive data and information systems

A two-pass surface extraction algorithm for adaptive finite-element meshes is presented in the context of a visualization study for a particle impact and a turbine-blade containment problem. The direct use of finite-element data structures for the computation of external surfaces, surface normals, and derived physical qualities is discussed. An overview of the in-betweening which accounts for rigid body dynamics effects is presented, with a brief discussion of a direct-to-videodisk animation strategy

This case study is a result of a six-week feasibility exercise, the aim of which was to explore the extend to which existing visualization software can be used for visualizing ISIS neutron scattering data. ISIS is an experimental facility devoted to the use of pulsed neutrons and muons to investigate the microscopic structure and dynamics of all classes of condensed matter. The feasibility study demonstrated the benefits of using visualization in exploring material science data, and also proved that it is possible to satisfy most of the requirements ISIS researchers place on a software environment by using application visualization systems (AVSs), and without writing any new code. The problems encountered and possible solutions are discussed

The visualization of 3-D second-order tensor fields and matrix data is studied. The general problem of visualizing unsymmetric real or complex Hermitian second-order tensor fields can be reduced to the simultaneous visualization of a real and symmetric second-order tensor field and a real vector field. The emphasis is on exploiting the mathematical properties of tensor fields in order to facilitate their visualization and to produce a continuous representation of the data. The focus is on interactively sensing and exploring real and symmetric second-order tensor data by generalizing the vector notion of streamline to the tensor concept of hyperstreamline. The importance of a structural analysis of the data field analogous to the techniques of vector field topology extraction in order to obtain a unique and objective representation of second-order tensor fields is stressed

Techniques for visualizing a simulated air flow in a clean room are developed by using an efficient cell traverse of tetrahedral cells generated from irregular volumes. The proposed techniques, probing and stream line display, are related to the measurement techniques used in actual clean rooms. The efficient traverse makes it possible to move freely around a given irregular volume and to spawn off stream lines. A successful application of these techniques to a problem in a clean room is also described

Reports from five research centers involved with atmospheric and environmental visualization issues are presented in this case study. Visualization with heterogeneous computer architectures is highlighted in the US EPA Scientific Visualization Center discussion. The NASA Marshall Space Flight Center effort to develop the multidimensional analysis of sensor systems (MASS) environment is presented. Florida State University's building of a new scientific visualization package, Sci An, is reported. This is followed by a discussion of the design and implementation of VIS-AD, an experimental laboratory for developing scientific algorithms, at the University of Wisconsin-Madison. The visualization of global atmospheric data at IBM Thomas J. Watson Research Center is highlighted

A three-dimensional finite-element hydrodynamic model was constructed to simulate tidal cycles in Galveston Bay over a one-year period in order to view changes in water velocities and salinity. A project undertaken to visualize the simulation results is reported. The project comprised analyzing model requirements and determining suitable visualization techniques, visualizing a preliminary, smaller-scale model to verify the techniques; and visualizing the full-scale model. Problems encountered and resolutions of problems at each stage are described. Validation, as well as insights revealed about the model through the preliminary and final visualization, are discussed. Current application of visualization techniques to the model is reported

A visualization technique that makes it possible to display and analyze line count profile data is described. The technique is to make a reduced picture of code with the line execution counts identified with color. Hot spots are shown in red, warm spots in orange, and so on. It is possible to identify nonexecuted code and nonexecutable code such as declarations and static tables

Experiments in visualizing implications of landscape planning and design decisions using a combination of GIS, CAD, and video animation technology are described. Simple grid-cell GIS databases and site-scale polygonal models are used to provide visualizations of site planning design proposals and environmental impact, with both static and animated images. Rather than pursuing photo-realistic simulations, the focus is on how abstractions and representational conventions can be used to gauge visual and environmental effects of proposals for landscape change, in a dynamic interactive computer-aided design environment

The relationship between gravity and topography to study subseafloor structures is discussed. Specifically, analysis of the dynamics of seafloor spreading using satellite altimetry is described. The visualization of satellite altimetry data and the limitations of such applications are presented

A Universe mapping project at the Harvard-Smithsonian Center for Astrophysics (CfA), called the CfA Redshift Survey, is described. The line-of-sight recession velocities of galaxies are measured by identifying absorption and emission lines in their spectra. With the two angular positions of a galaxy on the sky and a measurement of its red-shift, each galaxy can be placed in a three-dimensional (3-D) map of the Universe. It is shown that visualization techniques are important for exploring and analyzing the data, for comparing the data with models, and for designing the future. Computer animation of the data is a way of bringing the maps before the public

In order to visualize both clouds and wind in climate simulations, clouds were rendered using a 3D texture which was advected by the wind flow. The simulation is described. Rendering, the advection of texture coordinates, and haze effects are discussed. Results are presented

A prototype implementation of a splatting volume renderer (SVR) on a commercially available distributed memory MIMD (multiple instruction stream, multiple data stream) parallel processor, the nCUBE2, is described. Some relatively good rendering times can be achieved with the nCUBE SVR. Message-passing bottlenecks occur when large numbers of floating-point values have to be collected from every processor for every picture. For large images this is a severe limitation. An initial implementation of a SVR on a distributed memory parallel computer demonstrates the need for parallel computers with high-bandwidth connections between processors, and also for new parallelizable volume rendering algorithms