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VisPort: Web-Based Access to Community-Specific Visualization Functionality [Shedding New Light on Exploding Stars: Visualization for TeraScale Simulation of Neutrino-Driven Supernovae (Final Technical Report)]

Description: The VisPort visualization portal is an experiment in providing Web-based access to visualization functionality from any place and at any time. VisPort adopts a service-oriented architecture to encapsulate visualization functionality and to support remote access. Users employ browser-based client applications to choose data and services, set parameters, and launch visualization jobs. Visualization products – typically images or movies – are viewed in the user’s standard Web browser. VisPort emphasizes visualization solutions customized for specific application communities. Finally, VisPort relies heavily on XML, and introduces the notion of visualization informatics -“ the formalization and specialization of information related to the process and products of visualization.
Date: June 30, 2007
Creator: Baker, M Pauline
Partner: UNT Libraries Government Documents Department

Investigations of Slot Configurations for Film-Cooled Turbine Blades by Flow Visualization Methods

Description: Memorandum presenting a procedure for obtaining qualitative information on the effectiveness of different slot configurations to make the flow of the cooling air visible. Two methods are utilized: one utilizes the traces caused by a reaction between paint spread over the blade surface and a gas mixed with the cooling air, while the other utilized smoke mixed with the cooling air to make it visible. From the visual observations, the use of a continuous slot as a means of creating the cooling film over the blade surface appeared to be superior to the use of holes or grooves.
Date: October 10, 1950
Creator: Eckert, E. R. G.; Jackson, Thomas W. & Francisco, Allen C.
Partner: UNT Libraries Government Documents Department

Visualization of rotor tip secondary flows with blade tip air discharge and suction in a low-speed turbine

Description: Smoke was used to visualize outer-wall secondary flows in a low-speed turbine utilizing rotor tip air discharge and suction. Photographs as well as visual observations of the effect of tip air discharge and suction were made by independently varying the direction and quantity of the tip air discharge and suction, and varying tip clearance, and main-stream air speed. In addition, the cross-sectional area of the hollow blade discharge opening was varied for the case of tip air discharge.
Date: August 17, 1956
Creator: Kofskey, Milton G. & Allen, Hubert W.
Partner: UNT Libraries Government Documents Department

Visualization study of secondary flows in turbine rotor tip regions

Description: Report presenting a visualization study using smoke to see the secondary-flow phenomena in the rotor-blade tip region of a low-speed turbine. Measurements of the factors affecting the flow patterns were recorded from visual observations. Results regarding a general description of the smoke patterns, shroud boundary-layer considerations, transition rotor tip speed, and high-speed-turbine operating conditions are provided.
Date: September 1955
Creator: Allen, Hubert W. & Kofskey, Milton G.
Partner: UNT Libraries Government Documents Department

DOE's SciDAC Visualization and Analytics Center for EnablingTechnologies -- Strategy for Petascale Visual Data Analysis Success

Description: The focus of this article is on how one group of researchersthe DOE SciDAC Visualization and Analytics Center for EnablingTechnologies (VACET) is tackling the daunting task of enabling knowledgediscovery through visualization and analytics on some of the world slargest and most complex datasets and on some of the world's largestcomputational platforms. As a Center for Enabling Technology, VACET smission is the creation of usable, production-quality visualization andknowledge discovery software infrastructure that runs on large, parallelcomputer systems at DOE's Open Computing facilities and that providessolutions to challenging visual data exploration and knowledge discoveryneeds of modern science, particularly the DOE sciencecommunity.
Date: October 1, 2007
Creator: Bethel, E. Wes; Johnson, Chris; Aragon, Cecilia; Prabhat, ???; Rubel, Oliver; Weber, Gunther et al.
Partner: UNT Libraries Government Documents Department

Extreme Scaling of Production Visualization Software on Diverse Architectures

Description: We present the results of a series of experiments studying how visualization software scales to massive data sets. Although several paradigms exist for processing large data, we focus on pure parallelism, the dominant approach for production software. These experiments utilized multiple visualization algorithms and were run on multiple architectures. Two types of experiments were performed. For the first, we examined performance at massive scale: 16,000 or more cores and one trillion or more cells. For the second, we studied weak scaling performance. These experiments were performed on the largest data set sizes published to date in visualization literature, and the findings on scaling characteristics and bottlenecks contribute to understanding of how pure parallelism will perform at high levels of concurrency and with very large data sets.
Date: December 22, 2009
Creator: Childs, Henry; Pugmire, David; Ahern, Sean; Whitlock, Brad; Howison, Mark; Weber, Gunther et al.
Partner: UNT Libraries Government Documents Department

Query-Driven Visualization of Time-Varying Adaptive Mesh Refinement Data

Description: The visualization and analysis of AMR-based simulations is integral to the process of obtaining new insight in scientific research. We present a new method for performing query-driven visualization and analysis on AMR data, with specific emphasis on time-varying AMR data. Our work introduces a new method that directly addresses the dynamic spatial and temporal properties of AMR grids which challenge many existing visualization techniques. Further, we present the first implementation of query-driven visualization on the GPU that uses a GPU-based indexing structure to both answer queries and efficiently utilize GPU memory. We apply our method to two different science domains to demonstrate its broad applicability.
Date: August 1, 2008
Creator: Gosink, Luke J.; Anderson, John C.; Bethel, E. Wes & Joy, Kenneth I.
Partner: UNT Libraries Government Documents Department

Interactive Remote and Distributed Visualization of Fusion Simulation Results

Description: The NERSC center has unique resources that are especially tailored for interactive, high performance remote visualization. The central interactive visualization resource is Escher.nersc.gov, which is a large symmetric multiprocessor equipped with multiple gigabit interconnects to NERSC storage systems, as well as a large amount of main memory and substantial directly attached storage. Using Escher, we employ a pipelined architecture to support the demands of interactive, high-performance remote visualization. The pipelined architecture refers to an assembly-line organization of software ''workers'' that each contribute to an overall work flow. The first worker in the assembly line the server runs interactively in parallel on Escher. Parallel execution of the server provides substantial I/O and processing capabilities where it is needed close to the data. The second worker in the assembly line runs on the scientists workstation in their office, and performs 3D rendering at interactive rates. Visualization results geometry are transmitted between the two stages in the pipeline. This combination has proven effective at providing interactive 3D scientific visualization capabilities to remotely located NERSC users. Amortizing data I/O and visualization processing over parallel processors located close to the data provides capabilities that are simply not available on any desktop platform. These capabilities are an example of NERSCs commitment to providing the best possible tools and infrastructure to the computational science community.
Date: January 1, 2004
Creator: Siegerist, C.; Shalf, J.; Bethel, E. Wes & Siegerist, Cristina
Partner: UNT Libraries Government Documents Department

TreeQ-VISTA: An Interactive Tree Visualization Tool with Functional Annotation Query Capabilities

Description: Summary: We describe a general multiplatform exploratorytool called TreeQ-Vista, designed for presenting functional annotationsin a phylogenetic context. Traits, such as phenotypic and genomicproperties, are interactively queried from a relational database with auser-friendly interface which provides a set of tools for users with orwithout SQL knowledge. The query results are projected onto aphylogenetic tree and can be displayed in multiple color groups. A richset of browsing, grouping and query tools are provided to facilitatetrait exploration, comparison and analysis.Availability: The program,detailed tutorial and examples are available online athttp://genome-test.lbl.gov/vista/TreeQVista.
Date: May 7, 2007
Creator: Gu, Shengyin; Anderson, Iain; Kunin, Victor; Cipriano, Michael; Minovitsky, Simon; Weber, Gunther et al.
Partner: UNT Libraries Government Documents Department

Generalized Framework and Algorithms for Illustrative Visualization of Time-Varying Data on Unstructured Meshes

Description: Photo- and physically-realistic techniques are often insufficient for visualization of simulation results, especially for 3D and time-varying datasets. Substantial research efforts have been dedicated to the development of non-photorealistic and illustration-inspired visualization techniques for compact and intuitive presentation of such complex datasets. While these efforts have yielded valuable visualization results, a great deal of work has been reproduced in studies as individual research groups often develop purpose-built platforms. Additionally, interoperability between illustrative visualization software is limited due to specialized processing and rendering architectures employed in different studies. In this investigation, a generalized framework for illustrative visualization is proposed, and implemented in marmotViz, a ParaView plugin, enabling its use on variety of computing platforms with various data file formats and mesh geometries. Detailed descriptions of the region-of-interest identification and feature-tracking algorithms incorporated into this tool are provided. Additionally, implementations of multiple illustrative effect algorithms are presented to demonstrate the use and flexibility of this framework. By providing a framework and useful underlying functionality, the marmotViz tool can act as a springboard for future research in the field of illustrative visualization.
Date: December 1, 2012
Creator: Rattner, Alexander S.; Guillen, Donna Post & Joshi, Alark
Partner: UNT Libraries Government Documents Department

A visualization study of secondary flows in cascades

Description: Flow-visualization techniques are employed to ascertain the streamline patterns of the nonpotential secondary flows in the boundary layers of cascades, and thereby to provide a basis for more extended analyses in turbomachines. The three-dimensional deflection of the end-wall boundary layer results in the formation of a vortex within each cascade passage. The size and tightness of the vortex generated depend upon the main-flow turning in the cascade passage. Once formed, a vortex resists turning in subsequent blade rows, with consequent unfavorable angles of attack and possible flow disturbances on the pressure surfaces of subsequent blade rows when the vortices impinge on these surfaces. Two major tip-clearance effects are observed, the formation of a tip-clearance vortex and the scraping effect of a blade with relative motion past the wall boundary layer. The flow patterns indicate methods for improving the blade tip-loading characteristics of compressors and of low- and high-speed turbulence.
Date: 1954
Creator: Herzig, Howard Z.; Hansen, Arthur G. & Costello, George R.
Partner: UNT Libraries Government Documents Department

Smoke study of nozzle secondary flows in a low-speed turbine

Description: Still and motion pictures were made of boundary-layer and wake secondary-flow phenomena visualized by smoke. Two annular cascades of turbine nozzles were used, both designed for constant discharge angle but differing in blade shape and suction-surface velocity distribution. Flows were similar to those obtained with pressure and angle measurements at near-sonic airspeeds. Boundary-layer cross-channel and trailing-edge radial flows caused vortices and an accumulation of low-momentum air at the hub, which may affect flow in following blade rows. Motion of a downstream rotor blade row produced pulsations in trailing-edge radial flow. The motion-picture supplement may be obtained on loan from NACA Headquarters, Washington, D.C.
Date: November 1954
Creator: Kofskey, Milton G. & Allen, Hubert W.
Partner: UNT Libraries Government Documents Department

Methods of Visually Determining the Air Flow Around Airplanes

Description: "This report describes methods used by the National Advisory Committee for Aeronautics to study visually the air flow around airplanes. The use of streamers, oil and exhaust gas streaks, lampblack and kerosene, powdered materials, and kerosene smoke is briefly described. The generation and distribution of smoke from candles and from titanium tetrachloride are described in greater detail because they appear most advantageous for general application. Examples are included showing results of the various methods" (p. 1).
Date: July 1932
Creator: Gough, Melvin N. & Johnson, Ernest
Partner: UNT Libraries Government Documents Department

Regional and Local Data

Description: Video of the panel session "Regional and Local Data" at the 2017 Open Access Symposium. This video discusses the use of geospatial data at regional and local levels.
Date: May 19, 2017
Creator: Dailey, George; Tiwari, Chetan & Ramirez, Daniela
Partner: UNT Libraries

Letting the collections tell their story: Using Tableau for collection evaluation

Description: This presentation contains the workshop presented at the 2016 Library and Information Technology Association Forum pre-conference session. This workshop presentation includes an introduction to the Tableau Public software, data management, and developing dashboards.
Date: November 17, 2016
Creator: Harker, Karen; Klein, Janette & Parwani, Priya B.
Partner: UNT Libraries

SLAM using camera and IMU sensors.

Description: Visual simultaneous localization and mapping (VSLAM) is the problem of using video input to reconstruct the 3D world and the path of the camera in an 'on-line' manner. Since the data is processed in real time, one does not have access to all of the data at once. (Contrast this with structure from motion (SFM), which is usually formulated as an 'off-line' process on all the data seen, and is not time dependent.) A VSLAM solution is useful for mobile robot navigation or as an assistant for humans exploring an unknown environment. This report documents the design and implementation of a VSLAM system that consists of a small inertial measurement unit (IMU) and camera. The approach is based on a modified Extended Kalman Filter. This research was performed under a Laboratory Directed Research and Development (LDRD) effort.
Date: January 1, 2007
Creator: Rothganger, Fredrick H. & Muguira, Maritza M.
Partner: UNT Libraries Government Documents Department

A Global Stochastic Modeling Framework to Simulate and Visualize Epidemics

Description: Epidemics have caused major human and monetary losses through the course of human civilization. It is very important that epidemiologists and public health personnel are prepared to handle an impending infectious disease outbreak. the ever-changing demographics, evolving infrastructural resources of geographic regions, emerging and re-emerging diseases, compel the use of simulation to predict disease dynamics. By the means of simulation, public health personnel and epidemiologists can predict the disease dynamics, population groups at risk and their geographic locations beforehand, so that they are prepared to respond in case of an epidemic outbreak. As a consequence of the large numbers of individuals and inter-personal interactions involved in simulating infectious disease spread in a region such as a county, sizeable amounts of data may be produced that have to be analyzed. Methods to visualize this data would be effective in facilitating people from diverse disciplines understand and analyze the simulation. This thesis proposes a framework to simulate and visualize the spread of an infectious disease in a population of a region such as a county. As real-world populations have a non-homogeneous demographic and spatial distribution, this framework models the spread of an infectious disease based on population of and geographic distance between census blocks; social behavioral parameters for demographic groups. the population is stratified into demographic groups in individual census blocks using census data. Infection spread is modeled by means of local and global contacts generated between groups of population in census blocks. the strength and likelihood of the contacts are based on population, geographic distance and social behavioral parameters of the groups involved. the disease dynamics are represented on a geographic map of the region using a heat map representation, where the intensity of infection is mapped to a color scale. This framework provides a tool for public health personnel and ...
Date: May 2012
Creator: Indrakanti, Saratchandra
Partner: UNT Libraries