## Visual Analysis of Large Heterogeneous Social Networks by Semantic and Structural Abstractions
| Social network analysis is an active area of study beyond sociology. It uncovers the invisible relationships between actors in a network and provides understanding of social processes and behaviors. It has become an important technique in a variety of application areas such as the Web, organizational studies, and homeland security. This paper presents a visual analytics tool, OntoVis, for understanding large, heterogeneous social networks, in which nodes and links could represent different concepts and relations, respectively ... | |

## Layout of Multiple Views for Volume Visualization: A User Study
| Volume visualizations can have drastically different appearances when viewed using a variety of transfer functions. A problem then occurs in trying to organize many different views on one screen. We conducted a user study of four layout techniques for these multiple views. We timed participants as they separated different aspects of volume data for both time-invariant and time-variant data using one of four different layout schemes ... | |

## From Mesh Generation to Scientific Visualization: An End-to-End Approach to Parallel Supercomputing (DVD Proceedings)
| Traditionally, parallel supercomputing has focused on the inner kernel of scientific simulations: the solver. The front and back ends of the simulation pipeline--problem description and interpretation of the output--have taken a back seat to the solver when it comes to attention paid to scalability and performance, and are often relegated to offline, sequential computation. As the largest simulations move beyond the realm of the terascale and into the petascale, this decomposition in tasks and platforms becomes increasingly untenable. ... | |

## Interactive Multi-Scale Exploration for Volume Classification
| Filter banks are a class of signal processing techniques that can be used to reveal the local energy of a signal at multiple scales. Utilizing such filtering allows us to consider local texture and other data characteristics, and permits volume classification and visualization that cannot be accomplished easily using conventional, transfer function-based methods. Our filter bank approach increases the dimensionality, and thus, the complexity of the classification task ... | |

## SciVis, InfoVis -- bridging the community divide?!
| Scientific Visualization (SciVis) and Information Visualization (InfoVis) are well-established and often used terms in the research field of visualization. But instead of intuitively illustrating two research fields - with disjunctive goals, challenges, and approaches - which they are not, this terminology of SciVis vs. InfoVis rather represents a manifested community divide: there are SciVis researchers and there are InfoVis researchers (and there are only a few who appear on both sides), there are SciVis conferences/journals and there are InfoVis conferences/journals, etc ... | |

## Quantitative and Comparative Visualization Applied to Cosmological Simulations
| Cosmological simulations follow the formation of nonlinear structure in dark and luminous matter. The associated simulation volumes and dynamic range are very large, making visualization both a necessary and challenging aspect of the analysis of these datasets. Our goal is to understand sources of inconsistency between different simulation codes that are started from the same initial conditions. Quantitative visualization supports the definition and reasoning about analytically defined features of interest ... | |

## A Scalable, Hybrid Scheme for Volume Rendering Massive Data Sets
| We introduce a parallel, distributed memory algorithm for volume rendering massive data sets. The algorithm's scalability has been demonstrated up to 400 processors, rendering one hundred million unstructured elements in under one second. The heart of the algorithm is a hybrid approach that parallelizes over both the elements of the input data and over the pixels of the output image. At each stage of the algorithm, there are strong limits on how much work each processor performs, ensuring good parallel effciency ... | |

## Multi-Layered Image Caching for Distributed Rendering of Large Multiresolution Data
| The capability to visualize large volume datasets has applications in a myriad of scientic elds. This paper presents a large data visualization solution in the form of distributed, multiresolution, progressive processing. This solution reduces the problem of rendering a large volume data into many simple and independent problems that can be straightforwardly distributed to multiple computers. By completely decoupling rendering and display with image caching, we are able to maintain a high level of interactivity during exploration of the data, which is key to obtaining insights into the data ... | |

## Natural Visualization
| This paper demonstrates the prevalence of a shared haracteristic between visualizations and images of nature. We have analyzed visualization competitions and user studies of visualizations and found that the more preferred, better performing visualizations exhibit more natural characteristics. Due to our brain being wired to perceive natural images, testing a visualization for properties similar to those of natural images can help show how well our brain is capable of absorbing the data ... | |

## Simultaneous Classification of Time-Varying Volume Data Based on the Time Histogram
| An important challenge in the application of direct volume rendering to time-varying data is the specification of transfer functions for all time steps. Very little research has been devoted to this problem, however. To address this issue we propose an approach which allows simultaneous classification of the entire time series. We explore options for transfer function specification that are based, either directly or indirectly, on the time histogram ... | |

## Evaluating the Effectiveness of Tree Visualization Systems for Knowledge Discovery
| User studies, evaluations, and comparisons of tree visualization systems have so far focused on questions that can readily be answered by simple, automated queries without needing visualization. Studies are lacking on the actual use of tree visualization in discovering intrinsic, hidden, non-trivial and potentially valuable knowledge. We have thus formulated a set of tree exploration tasks not previously considered and have performed user studies and analysis to determine how visualization helps users to perform these tasks ... | |

## Ultra Scale Visualization
| Large parallel computing systems give scientists the power to model and visualize physical phenomena and chemical processes at a stunning degree of precision and sophistication leading to profound levels of insight and understanding. I will introduce new techniques and concepts promising us to visualize and explore terabyte-scale data to its full extent, and show the impact of these new technologies on a wide range of science endeavors from turbulent combustion to fusion, from meteorology to geophysics, from particle physics to astrophysics ... | |

## Visualization for Cybersecurity
| Networked computers have become an integral part of our everyday life, used for a variety of purposes at home, in the workplace, and at schools. They are so ubiquitous and easy to access that they are also vulnerable. Any computer exposed to the Internet is likely to be regularly scanned and attacked by both automated and manual means. Both organizations and individuals are making every effort to build and maintain trustworthy computing systems ... | |

## BiblioViz: A System for Visualizing Bibliography Information
| The InfoVis 2004 contest led to the development of several bibliography visualization systems. Even though each of these systems offers some unique views of the bibliography data, there is no single best system offering all the desired views. We have thus studied how to consolidate the desirable unctionalities of these systems into a cohesive design. We have also designed a few novel visualization methods ... | |

## Cyber Security Through Visualization
| Networked computers are subject to attack, misuse, and abuse. Organizations and individuals are making every effort to build and maintain trustworthy computing systems. The main strategy is to closely monitor and inspect network activities by collecting and analyzing data about the network traffic and the trails of system usage. The analysis usually requires large amounts of finely detailed, high-dimensional data to enable analysts to uncover hidden threats and make calculated predictions in a timely fashion. ... | |

## 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
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## 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
| ... |