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CreatorTitleDescriptionSubjectDate
1 Johnson, Christopher R.; Parker, Steven G.; Whitaker, Ross T.; Hansen, Charles D.Computational field visualizationToday, scientists, engineers, and medical researchers routinely use computers to simulate complex physical phenomena. Such simulations present new challenges for computational scientists, including the need to effectively analyze and visualize complex three-dimensional data. As simulations become mo...Volume rendering; Isosurface extraction; Ray tracing; Multi-field visualizations2001
2 Zhang, LixinDescription of functionality of the impulse memory controllerThis document describes the functionality and control flow models for each component of the impulse main memory controller.Impulse memory controller2001
3 Balasubramonian, RajeevDynamically allocating processor resources between nearby and distant ILPModern superscalar processors use wide instruction issue widths and out-of-order execution in order to increase instruction-level parallelism (ILP). Because instructions must be committed in order so as to guarantee precise exceptions, increasing ILP implies increasing the sizes of structures s...Instruction-level parallelism; Microarchitecture; Primary thread; Future thread; Instruction reuse buffer2001
4 Gopalakrishnan, GaneshFormal specification of the virtual component interface standard in the unified modeling languageAs part of our charge from the Virtual Sockets Interface Alliance we search for a notation in which standards documents can be precisely specified. We approach the specification for standard problem in the context of the Virtual Component Interface Standard. We propose six orthogonal axes of specifi...Unified Modeling Language2001
5 Chatterjee, Prosenjit; Gopalakrishnan, GaneshFormally specifying memory consistency models and automatically generating executable specificationsMemory ordering properties of shared memory multiprocessors are more subtle and less well understood than cache coherence. These properties tend to be processor or platform specific and are not always formally specified. It is difficult to compare even those platforms whose memory ordering propert...Computer memory; Memory consistency models; Memory ordering; Shared memory multiprocessors2001
6 Johnson, Christopher R.Grid-enabling problem solving environments: a case study of SCIRun and NetSolveCombining the functionality of NetSolve, a grid-based middleware solution, with SCIRun, a graphically-based problem solving environment (PSE), yields a platform for creating and executing grid-enabled applications. Using this integrated system, hardware and/or software resources not previously ac...Grid computing; SCIRun; NetSolve; Problem solving environment; Numerical libraries; Parallel programming (Computer science)2001
7 Hansen, Charles D.; Hollerbach, John M.Improved calibration Framework for electromagnetic tracking devicesElectromagnetic trackers have many favorable characteristics but are notorious for their sensitivity to magnetic field distortions resulting from metal and electronic equipment in the environment. We categorize existing tracker calibration methods and present an improved technique for reducing stati...Electromagnetic tracking; Tracking devices2001
8 Hansen, Charles D.Interactive texture-based volume rendering for large data setsVisualization is an integral part of scientific computation and simulation. State-of-the-art simulations of physical systems can generate terabytes to petabytes of time-varying data where a single time step can contain more than a gigabyte of data per variable. As memory sizes continue to increase, ...Parallel rendering; Volume rendering; TRex2001
9 Hansen, Charles D.Interactive volume rendering using multi-dimensional transfer functions and direct manipulation widgetsMost direct volume renderings produced today employ one-dimensional transfer functions, which assign color and opacity to the volume based solely on the single scalar quantity which comprises the dataset. Though they have not received widespread attention, multi-dimensional transfer functions are a ...Volume rendering; Volume visualization; Direct volume rendering; Multidimensional transfer functions; Direct manipulation widgets; Graphics hardware2001
10 Hansen, Charles D.Interactive volume rendering using multi-dimensional transfer functions and direct manipulation widgetsMost direct volume renderings produced today employ onedimensional transfer functions, which assign color and opacity to the volume based solely on the single scalar quantity which comprises the dataset. Though they have not received widespread attention, multi-dimensional transfer functions are a v...Volume rendering; Volume visualization; Direct volume rendering; Multidimensional transfer functions; Direct manipulation widgets; Graphics hardware2001
11 Henderson, Thomas C.Leadership protocol for S-NetsSmart Sensor Networks are collections of non-mobile devices (S-elements) which can compute, communicate and sense the environment; they must be able to create local groups of devices (S-cliques). We propose here a protocol to solve the leadership problems for S-Nets. We sketch the correctness of thi...Smart Sensor Networks; S-Nets2001
12 Riloff, Ellen M.Looking under the hood: tools for diagnosing your question answering engineIn this paper we analyze two question answering tasks : the TREC-8 question answering task and a set of reading comprehension exams. First, we show that Q/A systems perform better when there are multiple answer opportunities per question. Next, we analyze common approaches to two subproblems: ter...TREC-8; Performance2001
13 Parker, Steven G.Massively parallel software rendering for visualizing large-scale data setsFor some time, researchers have done production visualization almost exclusively using high-end graphics workstations. They routinely archived and analyzed the outputs of simulations running on massively parallel supercomputers. Generally, a feature extraction step and a geometric modeling step t...Parallel rendering; Volume rendering; Ray tracing; Isosurfacing2001
14 Shirley, Peter S.Natural image statistics for computer graphicsThe class of all natural images is an infinitely small fraction of all possible images. The structure of natural images can be statistically modeled, revealing striking regularities. The human visual system appears to be optimized to view natural images, as opposed to any possible image, and therefo...Natural image2001
15 Hansen, Charles D.; Shirley, Peter S.Parallel point reprojectionImprovements in hardware have recently made interactive ray tracing practical for some applications. However, when the scene complexity or rendering algorithm cost is high, the frame rate is too low in practice. Researchers have attempted to solve this problem by caching results from ray tracing an...Point reprojection; Ray tracing2001
16 Shirley, Peter S.Parallel point reprojectionImprovements in hardware have recently made interactive ray tracing practical for some applications. However, when the scene complexity or rendering algorithm cost is high, the frame rate is too low in practice. Researchers have attempted to solve this problem by caching results from ray tracing and...Point projection; Ray tracing; Render cache2001
17 Parker, Steven G.; Smith, Philip J.; Johnson, Christopher R.Parallelization and integration of fire simulations in the Uintah PSEA physics-based stand-alone serial code for fire simulations is integrated in a unified computational framework to couple with other disciplines and to achieve massively parallel computation. Uintah, the computational framework used, is a component-based visual problem-solving environment developed...Uintah; Problem solving environment2001
18 Gopalakrishnan, GaneshPerformance studies of PV: an On-the-fly model-checker for LTL-X featuring selective caching and partial order reductionWe present an enumerative model-checker PV that uses a new partial order reduction algorithm called Twophase. This algorithm does not use the in-stack check to implement the proviso, making the combination of Twophase with on-the-fly LTL-X model-checking based on nested depth-first search, as well a...Model-checker; PV; Performance; On-the-fly; Partial order reduction algorithm;' Twophase2001
19 Hansen, Charles D.; Johnson, Christopher R.Prototype system for synergistic data displayMultimodal interfaces have been shown to increase user performance for a variety of tasks. We have been investigating the synergistic benefits of haptic scientific visualization using an integrated, semi-immersive virtual environment. The Visual Haptic Workbench provides multimodal interaction; imm...Visual Haptic Workbench; Haptic interfaces; Scientific visualization2001
20 Balasubramonian, RajeevReducing the complexity of the register file in dynamic superscalar processorsDynamic superscalar processors execute multiple instructions out-of-order by looking for independent operations within a large window. The number of physical registers within the processor has a direct impact on the size of this window as most in-flight instructions require a new physical register a...Dynamic superscalar processors; Register file; Instruction-level parallelism; Microarchitecture; Reorder buffer2001
21 Baker, Jason; Hsieh, Wilson C.Runtime aspect weaving through metaprogrammingWe describe an extension to the Java language, Handi-Wrap, that supports weaving aspects into code at runtime. Aspects in Handi-Wrap take the form of method wrappers, which allow aspect code to be inserted around method bodies like advice in AspectJ. Handi- Wrap offers several advantages over sta...Metaprogramming; Runtime; Handi-Wrap2001
22 Shirley, Peter S.; Parker, Steven G.Temporally coherent interactive ray tracingAlthough ray tracing has been successfully applied to interactively render large datasets, supersampling pixels will not be practical in interactive applications for some time. Because large datasets tend to have subpixel detail, one-sample-per-pixel ray tracing can produce visually distracting popp...Temporally coherent; interactive ray tracing; large datasets2001
23 Gopalakrishnan, GaneshTowards a formal model of shared memory consistency for intel itaniumWe provide a simple formal model for ItaniumTM shared memory consistency [1, 2] covering a core set of instructions. Existing descriptions of Itanium shared memory consistency are based on an informal collection of ordering rules as well as several examples. Our operational model employs employs wid...formal model; shared memory consistency; ItaniumTM; Itanium2001
24 Van Uitert, Robert; Weinstein, David; Johnson, Christopher R.Volume currents in forward and inverse MEG simulations using realistic head modelsMany magnetoencephalography (MEG) forward and inverse simulation models employ spheres, a singular shape which does not require consideration of volume currents. With more realistic, inhomogenous, anisotropic, non-spherical head models, volume currents cannot be ignored. We verify the accuracy of ...Forward MEG, Inverse MEG, Source localization, Volume currents, Finite element method2001
25 Hansen, Charles D.Wavelet representation of contour setsWe present a new wavelet compression and multiresolution modeling approach for sets of contours (level sets). In contrast to previous wavelet schemes, our algorithm creates a parametrization of a scalar field induced by its contours and compactly stores this parametrization rather than function valu...Contours; Geometry compression; Isosurfaces; Level sets; Multiresolution methods; Wavelets2001
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