## A Model for the Visualization Exploration Process
| The current state of the art in visualization research places a strong emphasis on different techniques to derive insight from disparate types of data. However, little work has investigated the visualization process itself. The information content of the visualization process—the results, history, and relationships between those results—is addressed by this work. A characterization of the visualization process is discussed, leading to a general model of the visualization exploration process ... | |

## Kinetic Visualization: A Technique for Illustrating 3D Shape and Structure
| Motion provides strong visual cues for the perception of shape and depth, as demonstrated by cognitive scientists and visual artists. This paper presents a novel visualization technique – kinetic visualization-that uses particle systems to add supplemental motion cues which can aid in the perception of shape and spatial relationships of static objects. Based on a set of rules following perceptual and physical principles, particles flowing over the surface of an object not only bring out, but also attract attention to, essential information on the shape of the object that might not be readily visible with conventional rendering that uses lighting and view changes ... | |

## Case Study: Interactive Visualization for Internet Security
| Internet connectivity is defined by a set of routing protocols which let the routers that comprise the Internet backbone choose the best route for a packet to reach its destination. One way to improve the security and performance of Internet is to routinely examine the routing data. In this case study, we show how interactive visualization of Border Gateway Protocol (BGP) data helps characterize routing behavior, identify weaknesses in connectivity which could potentially cripple the ... | |

## ISpace: Interactive Volume Data Classification Techniques Using Independent Component Analysis
| This paper introduces an interactive classification technique for volume data, called ISpace, which uses Independent Component Analysis (ICA) and a multidimensional histogram of the volume data in a transformed space. Essentially, classification in the volume domain becomes equivalent to interactive clipping in the ICA space, which as demonstrated using several examples is more intuitive and direct for the user to classify data ... | |

## Visualization of Multidimensional, Multivariate Volume Data Using Hardware-accelerated Non-photorealistic Rendering Techniques
| This paper presents a set of feature enhancement techniques coupled with hardware-accelerated nonphotorealistic rendering for generating more perceptually effective visualizations of multidimensional, multivariate volume data, such as those obtained from typical computational fluid dynamics simulations. For time-invariant data, one or more variables are used to either highlight important features in another variable, or add contextural information to the visualization. For time-varying data, rendering of each time step also takes into account the values at neighboring time steps to reinforce the perception of the changing features in the data over time ... | |

## Scalable Self-Orienting Surfaces: A Compact, Texture-Enhanced Representation for Interactive Visualization of 3D Vector Fields
| This paper presents a study of field line visualization techniques. | |

## A Hardware-Assisted Hybrid Rendering Technique for Interactive Volume Visualization
| The scientific simulation and three-dimensional imaging systems in use today are producing large quantities of data that range from gigabytes to petabytes in size. Direct volume rendering, using hardware-based three-dimensional textures, is a common technique for interactively exploring these data sets. The most serious drawback of this approach is the finite amount of available texture memory. In this paper we introduce a hybrid volume rendering technique based on the use of hardware texture mapping and pointbased rendering ... | |

## A Visual Technique for Internet Anomaly Detection
| The Internet can be made more secure and efﬁcient with effective anomaly detection. In this paper, we describe a visual method for anomaly detection using archived Bor der Gateway Protocol (BGP) data. A special encoding of IP addresses built into an interactive visual interface de sign allows a user to quickly detect anomalous Origin AS changes by browsing through visual representations of se lected aspects of the data ... | |

## Interactivity is the Key to Expressive Visualization
| Scientific visualization is widely used for gaining insight into phenomena through data exploration and creating imagery that can be used to illustrate these phenomena to others. Interactive rendering has long been valued in visualization as a means of facilitating more effective exploration. More recently, non-photorealistic rendering (NPR) has been applied to scientific visualization, which consists of using artistically inspired techniques for the creation of more expressive visualizations ... | |

## A Hardware-Assisted Scalable Solution for Interactive Volume Rendering of Time-Varying Data
| We present a scalable volume rendering technique that exploits lossy compression and low-cost commodity hardware to permit highly interactive exploration of time-varying scalar volume data. A palette-based decoding technique and an adaptive bit allocation scheme are developed to fully utilize the texturing capability of a commodity 3-D graphics card. Using a single PC equipped with a modest amount of memory, a texture capable graphics card, and an inexpensive disk array, we are able to render hundreds of time steps of regularly gridded volume data (up to 42 millions voxels each time step) at interactive rates ... | |

## Recent Advances in Non-Photorealistic Rendering for Art and Visualization
| This course gives a concise introduction to non-photorealistic rendering (NPR): generation of artistic imagery and perceptually effective scientific visualization. The lecturers will deliver working knowledge of fundamental NPR techniques and some of the advanced approaches at the forefront of NPR research. Topics include the relevance of visual perception and artistic techniques to NPR, brush-stroke rendering, paint-inspired techniques, hardware-accelerated NPR, and parallel NPR. ... | |

## Virtual Clay Modeling Using Adaptive Distance Fields
| This paper describes an approach for the parametrization and modeling of objects represented by adaptive distance fields (ADFs). ADFs support the construction of powerful solid modeling tools. They can represent surfaces of arbitrary and even changing topology, while providing a more intuitive user interface than control-point based structures such as B-splines. Using the octree structure, an adaptively refined quadrilateral mesh is constructed that is topologically equivalent to the surface ... | |

## Hardware-Accelerated Parallel Non-Photorealistic Volume Rendering
| Non-photorealistic rendering can be used to illustrate subtle spatial relationships that might not be visible with more realistic rendering techniques. We present a parallel hardware-accelerated rendering technique, making extensive use of multi-texturing and paletted textures, for the interactive non-photorealistic visualization of scalar volume data. With this technique, we can render a 512512512 volume using non-photorealistic techniques that include tone-shading, silhouettes, gradient-based enhancement, and color depth cueing, as shown in the images on the color plate, at multiple frames second ... | |

## VG Cluster: A Low-Cost Solution for Large-Scale Volume Visualization
| The VG cluster is a Linux PC cluster with a high-speed network interconnect, a hardware compositor, and a parallel volume renderer with highly optimized system software ... | |

## RINGS: A Technique for Visualizing Large Hierarchies
| We present RINGS, a technique for visualizing large trees with hundreds of thousands of nodes. We introduce a new ringed circular layout of nodes to make more efficient use of limited display space. RINGS provides the user with the means to specify areas of primary and secondary focus, and is able to show multiple foci without compromising understanding of the graph ... | |

## Interactive Visualization of Particle Beams for Accelerator Design
| We describe a hybrid data-representation and rendering technique for visualizing large-scale particle data generated from numerical modeling of beam dynamics. The basis of the technique is mixing volume rendering and point rendering according to particle density distribution, visibility, and the user's instruction. A hierarchical representation of the data is created on a parallel computer, allowing real-time partitioning into high-density areas for volume rendering, and low-density areas for point rendering ... | |

## Interactive Multi-Volume Visualization
| This paper is concerned with simultaneous visualization of two or more volumes, which may be from different imaging modalities or numerical simulations for the same subject of study. The main visualization challenge is to establish visual correspondences while maintaining distinctions among multiple volumes. One solution is to use different rendering styles for different volumes. Interactive rendering is required so the user can choose with ease an appropriate rendering style and its associated parameters for each volume ... | |

## Segmentation and 3D Visualization of High-Resolution Human Brain Cryosections
| We present a semi-automatic technique for segmenting a large cryo-sliced human brain data set that contains 753 highresolution RGB color images. This human brain data set presents a number of unique challenges to segmentation and visualization due to its size (over 7 GB) as well as the fact that each image not only shows the current slice of the brain but also unsliced "deeper layers" of the brain ... | |

## Advanced Visualization Technology for Terascale Particle Accelerator Simulations
| This paper presents two new hardware-assisted rendering techniques developed for interactive visualization of the terascale data generated from numerical modeling of extgeneration accelerator designs. The first technique, based on a hybrid rendering approach, makes possible interactive exploration of large-scale particle data from particle beam dynamics modeling. The second technique, based on a compact texture-enhanced representation, exploits the advanced features of commodity graphics cards to achieve perceptually effective visualization of the very dense and complex ... | |

## An Interactive Segmentation & Visualization Technique for Multispectral Volume Data
| ... | |

## Image Graphs - A Novel Approach to Visual Data Exploration
| For types of data visualization where the cost of producing images is high, and the relationship between the rendering parameters and the image produced is less than obvious, a visual representation of the exploration process can make the process more efficient and effective. Image graphs represent not only the results but also the process of data visualization. Each node in an image graph consists of an image and the corresponding visualization parameters used to produce it ... | |

## A Fast Volume Rendering Algorithm for Time-Varying Fields Using a Time-Step Partitioning (TSP) Tree
| This paper presents a fast volume rendering algorithm for timevarying fields. We propose a new data structure, called Time-Space Partitioning (TSP) tree, that can effectively capture both the spatial and the temporal coherence from a time-varying field. Using the proposed data structure, the rendering speed is substantially improved. In addition, our data structure helps to maintain the memory access locality and to provide the sparse data traversal so that our algorithm becomes suitable for large-scale out-of-core applications ... | |

## Visualization Case Studies: Drawing a Roadmap for Future Visualization
| Visualization has become an indispensable tool for scientific researchers to understand their data ånd communicate their findings. Appropriate visualization tools often lead scientists to new insights more quickly. Today, both instrument and computing technologies advance quickly, enhancing scientists' capability to study problems of increasing scale and complexity. ... | |

## Parallel Visualization of Large-scale Aerodynamics Calculations: A Case Study on the Cray T3E
| This paper reports the performance of a parallel volume rendering algorithm for visualizing a largescale unstructured-grid dataset produced by a three-dimensional aerodynamics simulation. This dataset, containing over 18 million tetrahedra, allows us to extend our performance results to a problem which is more than 30 times larger than the one we examined previously. This high resolution dataset also allows us to see fine, threedimensional features in the flow field ... | |

## Parallel Rendering of 3D AMR Data on the SGI/Cray T3E
| This paper describes work-in-progress on developing parallel visualization strategies for 3D Adaptive Mesh Refinement (AMR) data. AMR is a simple and powerful tool for modeling many important scientific and engineering problems. However, visualization tools for 3D AMR data are not generally available. Converting AMR data onto a uniform mesh would result in high storage requirements, and rendering the uniform-mesh data on an average graphics workstation can be painfully slow if not impossible ... | |

## R-Tree Retrieval of Unstructured Volume Data for Visualization
| ... | |

## A Java-Based Testbed for Volume Visualization
| This paper describes a Java-based visualization software testbed for experimenting with new ideas and rendering codes, as well as approaches for remote and collaborative visualization. This system allows visualization across the Internet from a web browser supporting the Java language. We also address issues in designing more intuitive ... | |

## Massively Parallel Volume Rendering
| We are developing techniques for massively parallel volume rendering, examining primarily the techniques of algorithms on general parallel computers. Research involves the use of the UCSC 4096 processor MasPar MP-2 and numerous workstations. Recent NSF funding shall provide a very high performance visualization platform on which we shall also do research. Important research topics are: what is the maximum performance attainable for volumetric visualization on any given parallel computer? What is the optimal algorithm for volume visualization for a general model of computation? Which interactivity features provide capabilities that allow new results to be discovered with volumetric data? ... | |

## A Parallel Pipelined Renderer for Time-Varying Volume Data
| This paper presents a strategy for efficiently rendering time-varying volume data on a distributed-memory parallel computer. Time-varying volume data take large storage space and visualizing them requires reading large files continuously or periodically throughout the course of the visualization process. Instead of using all the processors to collectively render one volume at a time, a pipelined rendering process is proposed by partitioning processors into groups to render multiple volumes concurrently ... | |

## Out-of-Core Streamline Visualization on Large Unstructured Meshes
| Most scientific visualization software systems have been designed for data that can fit into the physical memory of a single workstation. For many scientific applications, data at the desirable resolution can easily overwhelm the memory capacity of the scientist’s desktop workstation. This is particularly true for data obtained from three-dimensional aerodynamics calculations, where very fine unstructured tetrahedral meshes are needed to model arbitrarily complex configurations, such as an airplane ... | |

## A Scalable Parallel Cell-Projection Volume Rendering Algorithm for Three-Dimensional Unstructured Data
| ... | |

## 3D Shock Wave Visualization on Unstructured Grids
| A critical issue in understanding high speed flows is the study of shock waves. This paper summarizes our research on techniques for the detection and visualization of shock waves occuring in simulations of threedimensional flows on unstructured grids. Detection algorithms based on Mach number, density gradient and directional derivatives are compared using a data set from calculations of a transonic flow with a weak double shock around an airfoil ... | |

## Visualizing Vector Fields Using Line Integral Convolution and Dye Advection
| We present local and global techniques to visualize three-dimensional vector field data. Using the Line Integral Convolution (LIC) method to image the global vector field, our new algorithm allows the user to introduce colored “dye” into the vector field to highlight local flow features. A fast algorithm is proposed that quickly recomputes the dyed LIC images. In addition, we introduce volume rendering methods that can map the LIC texture on any contour surface and/or translucent region defined by additional scalar quantities, and can follow the advection of colored dye throughout the volume ... | |

## Efficient Streamline, Steamribbon, and Streamtube Constructions on Unstructured Grids
| Streamline construction is one of the most fundamental techniques for visualizing steady flow fields. Streamribbons and streamtubes are extensions for visualizing the rotation and the expansion of the flow. The paper presents efficient algorithms for constructing streamlines, streamribbons, and streamtubes on unstructured grids. A specialized Runge-Kutta method is developed to speed up the tracing of streamlines. Explicit solutions are derived for calculating the angular rotation rates of streamribbons and the radii of streamtubes ... | |

## Flow Visualization Using LIC-Based Dye Advection
| ... | |

## Runtime Volume Visualization for Parallel CFD
| This paper discusses some aspects of the design of a data distributed, massively parallel volume rendering library for runtime visualization of parallel computational fluid dynamics simulations in a message-passing environment. Unlike the traditional scheme in which visualization is a postprocessing step, the rendering is done in place on each node processor. Computational scientists who run large-scale simulations on a massively parallel computer can thus perform interactive monitoring of their simulations ... | |

## Volume Visualization of Airplane Wake Vortices
| ... | |

## Cloud Dispersion Properties in Visualization of Gas and Particle Mixing
| It is shown that cloud dispersion concepts can be used to visualize the dispersion and mixing of both massless or fluid particles and inertial particle systems. The cloud can interact with surfaces by sticking or rebounding the particles within the cloud. This method provides rapid feedback on mixing and dispersion processes and is computationally efficient enough to be interactive. Further insight can be obtained by using volume rendering so that the cloud content can also be visualized, not just the exterior surface of the cloud ... | |

## Fast Algorithms for Visualizing Fluid Motion in Steady Flow on Unstructured Grids
| The plotting of streamlines is an effective way of visualizing fluid motion in steady flows. Additional information about the flowfield, such as local rotation and expansion, can be shown by drawing in the form of a ribbon or tube. In this paper, we present efficient algorithms for the construction of streamlines, streamribbons and streamtubes on unstructured grids. A specialized version of the Runge-Kutta method has been developed to speed up the integration of particle pathes ... | |

## Parallel Volume Rendering
| ... | |

## Parallel Volume Ray-Casting for Unstructured-Grid Data on Distributed-Memory Architectures
| As computing technology continues to advance, computational modeling of scientific and engineering problems produces data of increasing complexity: large in size and unstructural in shape. Volume visualization of such data is a challenging problem. This paper proposes a distributed parallel solution that makes ray-casting volume rendering of unstructured-grid data practical. Both the data and the rendering process are distributed among processors ... | |

## Visualization of Particles and Gas Mixing
| ... | |

## Interactive Visualization of Multiphase Mixing in Steady-State CFD
| This paper describes an interactive technique for the visualization of the basic physical process of stochastic dispersion and mixing from steadystate CFD calculations. The mixing of massless particles or inertial particles is visualized by transforming the vector field from a traditionally Eulerian reference frame into a Lagrangian reference frame. Groups of articles are traced through the vector field for the mean path as well as their statistic ... | |

## Parallel Volume Rendering Using Binary-Swap Compositing
| ... | |

## A Distributed 3D Navier-Stokes Solver in Express
| The Navier-Stokes equations are central to applied scientific research. The complete set of threedimensional Navier-Stokes equations is very complex and thus requires a substantial amount of computer time as well as memory in order to obtain an accurate solution. The scalability in both processing power and memory space of distributed-memory parallel computers give promise of solving large scale three-dimensional scientific problems based on these equations ... | |

## Cloud Tracing in Convection-Diffusion Systems
| 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 ... | |

## A Data Distributed, Parallel Algorithm for Ray-traced Volume Rendering
| This paper presents a divide-and-conquer ray-traced volume rendering algorithm and a parallel image compositing method, along with their implementation and performance on the Connection Machine CM-5, and networked workstations. This algorithm distributes both the data and the computations to individual processing units to achieve fast, high-quality rendering of high-resolution data. The volume data, once distributed, is left intact. The processing nodes perform local ray tracing of their subvolume concurrently ... | |

## Distributed Combustion Simulations
| This paper reports research in progress. Two types of domain decomposition have been used in distributed computing with networked workstations for the numerical modeling of full-scale utility boilers. The numerical model is a three-dimensional combustion code that couples turbulent computational fluid dynamics with the chemical reaction process and the radiative heat transfer. Two approaches, here called microscale parallelism and macroscale parallelism, are proposed to study the intrinsic parallelism of typical combustion simulations ... | |

## Interactive Visualization of 3D Fluid Flow
| ... | |

## Virtual Smoke: An Interactive 3D Flow Visualization Technique
| A technique is given for computer visualization of simultaneous three-dimensional vector and scalar fields such as velocity and temperature in reacting fluid flow fields. The technique, which is called Virtual Smoke, simulates the use of colored smoke for experimental gaseous fluid flow visualization. However, it is noninvasive and can animate, in particular, the dynamic behaviors of steady-state or instantaneous flow fields obtained from numerical simulations ... | |

## A Distributed Solution and Visualization for 3D Flow Simulation
| ... | |

## Parallel Volume Visualization on Workstations
| ... | |

## Comparison of Maximum Intensity Projection and Volume Rendering Algorithms for Evaluation of Renal Artery Anatomy in Patients with Abdominal Aortic Aneurysm
| ... | |

## Volume Seedlings
| Recent advances in software and hardware technology have made direct ray-traced volume rendering of 3-d scalar data a feasible and effective method for imaging of the data’s contents. The time costs of these rendering techniques still do not permit full interaction with the data, and all of the parameters effecting the resulting images. This paper presents a set of real-time interaction techniques which have been developed to permit exploration of a volume data set ... | |

## Direct Numerical Simulation and Visualization of a Three Dimensional Planar Mixing Layer
| The coupling of the direct numerical simulation and visualization is useful because of the insight it provides into the development and formation of structures within the flowfield. The use of a volume-rendering technique for the visualization of a three-dimensional planar mixing layer is discussed. Graphical data in the form of color 'snapshots' and a video are presented to demonstrate the use of the volume-rendering method as a better way to understand the physics of turbulent flow ... | |

## Volume Seeds: A Volume Exploration Technique
| Ray-traced volume rendering has been shown to be an effective method for visualizing 3D scalar data. However, with currently available workstation technology, interactive volume exploration using conventional volume rendering is still too slow to be attractive. This paper describes an enhanced volume rendering method which allows interactive changes of rendering parameters such as colour and opacity maps. An innovative technique is provided which allows the user to plant a seed in the volume to rapidly modify local shading parameters ... | |

## TICL - A Type Inference System for Common Lisp
| Most current Common Lisp compilers generate more efficient code when supplied with data type information. However, in keeping with standard Lisp programming style, most programmers are reluctant to provide type information; they simply allow the run-time type system to manage the data types accordingly. To fill this gap, we have designed and implemented a type inference system for Common Lisp (TICL) ... | |

## A Distributed Algorithm for the Three Dimensional Compressible Navier-Stokes Equations
| ... |