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open access

Analysis of V-G Records From the SNJ-4 Airplane

Description: Report discusses an attempt to adapt a method of analysis of V-G data to predict the occurrences of large values of airspeed and acceleration from an SNJ-4 airplane; the data are presented as "flight envelopes". The flight envelopes "predict that, on average, in a stated number of flight hours, one airspeed, one positive acceleration, and one negative acceleration will exceed the envelope with equal probability of the accelerations being experienced at any airspeed" (from Discussion). The analysis method shows promise for predicting flight loads and speeds for airplanes on which loads due to maneuvers predominate.
Date: December 1945
Creator: Wilkerson, M. & Bennett, S. A.
Partner: UNT Libraries Government Documents Department
open access

Occam's Razor and Petascale Visual Data Analysis

Description: One of the central challenges facing visualization research is how to effectively enable knowledge discovery. An effective approach will likely combine application architectures that are capable of running on today?s largest platforms to address the challenges posed by large data with visual data analysis techniques that help find, represent, and effectively convey scientifically interesting features and phenomena.
Date: June 12, 2009
Creator: Bethel, E. Wes; Johnson, Chris; Ahern, Sean; Bell, John; Bremer, Peer-Timo; Childs, Hank et al.
Partner: UNT Libraries Government Documents Department
open access

Interfacing interactive data analysis tools with the grid: The PPDG CS-11 activity

Description: For today's physicists, who work in large geographically distributed collaborations, the data grid promises significantly greater capabilities for analysis of experimental data and production of physics results than is possible with today's ''remote access'' technologies. The goal of letting scientists at their home institutions interact with and analyze data as if they were physically present at the major laboratory that houses their detector and computer center has yet to be accomplished. The Particle Physics DataGrid project (www.ppdg.net) has recently embarked on an effort to ''Interface and Integrate Interactive Data Analysis Tools with the grid and identify Common Components and Services.'' The initial activities are to collect known and identify new requirements for grid services and analysis tools from a range of current and future experiments (ALICE, ATLAS, BaBar, D0, CMS, JLab, STAR, others welcome), to determine if existing plans for tools and services meet these requirements. Follow-on activities will foster the interaction between grid service developers, analysis tool developers, experiment analysis frame work developers and end user physicists, and will identify and carry out specific development/integration work so that interactive analysis tools utilizing grid services actually provide the capabilities that users need. This talk will summarize what we know of requirements for analysis tools and grid services, as well as describe the identified areas where more development work is needed.
Date: October 9, 2002
Creator: Olson, Douglas L. & Perl, Joseph
Partner: UNT Libraries Government Documents Department
open access

High Performance Multivariate Visual Data Exploration for Extremely Large Data

Description: One of the central challenges in modern science is the need to quickly derive knowledge and understanding from large, complex collections of data. We present a new approach that deals with this challenge by combining and extending techniques from high performance visual data analysis and scientific data management. This approach is demonstrated within the context of gaining insight from complex, time-varying datasets produced by a laser wakefield accelerator simulation. Our approach leverages histogram-based parallel coordinates for both visual information display as well as a vehicle for guiding a data mining operation. Data extraction and subsetting are implemented with state-of-the-art index/query technology. This approach, while applied here to accelerator science, is generally applicable to a broad set of science applications, and is implemented in a production-quality visual data analysis infrastructure. We conduct a detailed performance analysis and demonstrate good scalability on a distributed memory Cray XT4 system.
Date: August 22, 2008
Creator: Rubel, Oliver; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle et al.
Partner: UNT Libraries Government Documents Department
open access

Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters

Description: I present an analysis for fitting cosmological parameters from a Hubble Diagram of a standard candle with unknown intrinsic magnitude dispersion. The dispersion is determined from the data themselves, simultaneously with the cosmological parameters. This contrasts with the strategies used to date. The advantages of the presented analysis are that it is done in a single fit (it is not iterative), it provides a statistically founded and unbiased estimate of the intrinsic dispersion, and its cosmological-parameter uncertainties account for the intrinsic dispersion uncertainty. Applied to Type Ia supernovae, my strategy provides a statistical measure to test for sub-types and assess the significance of any magnitude corrections applied to the calibrated candle. Parameter bias and differences between likelihood distributions produced by the presented and currently-used fitters are negligibly small for existing and projected supernova data sets.
Date: December 10, 2010
Creator: Kim, Alex G
Partner: UNT Libraries Government Documents Department
open access

FastBit: Interactively Searching Massive Data

Description: As scientific instruments and computer simulations produce more and more data, the task of locating the essential information to gain insight becomes increasingly difficult. FastBit is an efficient software tool to address this challenge. In this article, we present a summary of the key underlying technologies, namely bitmap compression, encoding, and binning. Together these techniques enable FastBit to answer structured (SQL) queries orders of magnitude faster than popular database systems. To illustrate how FastBit is used in applications, we present three examples involving a high-energy physics experiment, a combustion simulation, and an accelerator simulation. In each case, FastBit significantly reduces the response time and enables interactive exploration on terabytes of data.
Date: June 23, 2009
Creator: Wu, Kesheng; Ahern, Sean; Bethel, E. Wes; Chen, Jacqueline; Childs, Hank; Cormier-Michel, Estelle et al.
Partner: UNT Libraries Government Documents Department
open access

Final report [The 15th Workshop on Electromagnetic Induction in the Earth, held 8/20-26/2000, and The 5th Magnetotelluric Data Interpretation Workshop, 8/17-19/2000]

Description: This document reports on how the DOE helped to support travel of students and scientists to the conferences in Brazil. Attendee names, funding, and session titles are listed.
Date: June 25, 2002
Creator: Alumbaugh, David L.
Partner: UNT Libraries Government Documents Department
open access

Visualization and Analysis of 3D Gene Expression Data

Description: Recent methods for extracting precise measurements ofspatial gene expression patterns from three-dimensional (3D) image dataopens the way for new analysis of the complex gene regulatory networkscontrolling animal development. To support analysis of this novel andhighly complex data we developed PointCloudXplore (PCX), an integratedvisualization framework that supports dedicated multi-modal, physical andinformation visualization views along with algorithms to aid in analyzingthe relationships between gene expression levels. Using PCX, we helpedour science stakeholders to address many questions in 3D gene expressionresearch, e.g., to objectively define spatial pattern boundaries andtemporal profiles of genes and to analyze how mRNA patterns arecontrolled by their regulatory transcription factors.
Date: October 25, 2007
Creator: Bethel, E. Wes; Rubel, Oliver; Weber, Gunther H.; Hamann, Bernd & Hagen, Hans
Partner: UNT Libraries Government Documents Department
open access

Planning for a program design for energy environmental analysis. Progress report, April 1, 1975--June 30, 1975

Description: The work reported in this second quarterly progress report has focussed on completing the first generation approach to the use of operational gaming in a regional assessment study program, writing an interim report on the work accomplished, and progress on the second generation approach which attempts to quantify the mechanisms identified in the first generation approach. The interim report, provided as an addendum to this report, provides detailed descriptions of the first generation work. This report provides a brief summary of the initial work on the second generation approach as well as the first generation approach. (auth)
Date: January 1, 1975
Creator: Denton, J C
Partner: UNT Libraries Government Documents Department
open access

Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data

Description: Our work combines and extends techniques from high-performance scientific data management and visualization to enable scientific researchers to gain insight from extremely large, complex, time-varying laser wakefield particle accelerator simulation data. We extend histogram-based parallel coordinates for use in visual information display as well as an interface for guiding and performing data mining operations, which are based upon multi-dimensional and temporal thresholding and data subsetting operations. To achieve very high performance on parallel computing platforms, we leverage FastBit, a state-of-the-art index/query technology, to accelerate data mining and multi-dimensional histogram computation. We show how these techniques are used in practice by scientific researchers to identify, visualize and analyze a particle beam in a large, time-varying dataset.
Date: August 28, 2008
Creator: Rubel, Oliver; Prabhat, Mr.; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R. et al.
Partner: UNT Libraries Government Documents Department
open access

An Improved Photometric Calibration of the Sloan Digital SkySurvey Imaging Data

Description: We present an algorithm to photometrically calibrate widefield optical imaging surveys, that simultaneously solves for thecalibration parameters and relative stellar fluxes using overlappingobservations. The algorithm decouples the problem of "relative"calibrations from that of "absolute" calibrations; the absolutecalibration is reduced to determining a few numbers for the entiresurvey. We pay special attention to the spatial structure of thecalibration errors, allowing one to isolate particular error modes indownstream analyses. Applying this to the SloanDigital Sky Survey imagingdata, we achieve ~;1 percent relative calibration errors across 8500sq.deg/ in griz; the errors are ~;2 percent for the u band. These errorsare dominated by unmodelled atmospheric variations at Apache PointObservatory. These calibrations, dubbed ubercalibration, are now publicwith SDSS Data Release 6, and will be a part of subsequent SDSS datareleases.
Date: September 30, 2007
Creator: Padmanabhan, Nikhil; Schlegel, David J.; Finkbeiner, Douglas P.; Barentine, J.C.; Blanton, Michael R.; Brewington, Howard J. et al.
Partner: UNT Libraries Government Documents Department
open access

Visual Data Exploration and Analysis - Report of the VisualizationBreakout Session at the 2003 SCaLeS Workshop - Volume II

Description: This document is the report from the Visualization breakoutsession at the SCaLeS (Science Case for Large-scale Simulation) workshopheld in 2003 in Bethesda, MD. The document presents current researchchallenges in visualization of large-scale scientific data.
Date: January 12, 2004
Creator: Bethel, E. Wes; Frank, Randall; Fulcomer, Samuel; Hansen, Chuck; Joy, Ken; Kohl, Jim et al.
Partner: UNT Libraries Government Documents Department
open access

Accelerating Network Traffic Analytics Using Query-DrivenVisualization

Description: Realizing operational analytics solutions where large and complex data must be analyzed in a time-critical fashion entails integrating many different types of technology. This paper focuses on an interdisciplinary combination of scientific data management and visualization/analysis technologies targeted at reducing the time required for data filtering, querying, hypothesis testing and knowledge discovery in the domain of network connection data analysis. We show that use of compressed bitmap indexing can quickly answer queries in an interactive visual data analysis application, and compare its performance with two alternatives for serial and parallel filtering/querying on 2.5 billion records worth of network connection data collected over a period of 42 weeks. Our approach to visual network connection data exploration centers on two primary factors: interactive ad-hoc and multiresolution query formulation and execution over n dimensions and visual display of then-dimensional histogram results. This combination is applied in a case study to detect a distributed network scan and to then identify the set of remote hosts participating in the attack. Our approach is sufficiently general to be applied to a diverse set of data understanding problems as well as used in conjunction with a diverse set of analysis and visualization tools.
Date: July 29, 2006
Creator: Bethel, E. Wes; Campbell, Scott; Dart, Eli; Stockinger, Kurt & Wu,Kesheng
Partner: UNT Libraries Government Documents Department
open access

Towards a Real-time Transient Classification Engine

Description: Temporal sampling does more than add another axis to the vector of observables. Instead, under the recognition that how objects change (and move) in time speaks directly to the physics underlying astronomical phenomena, next-generation wide-field synoptic surveys are poised to revolutionize our understanding of just about anything that goes bump in the night (which is just about everything at some level). Still, even the most ambitious surveys will require targeted spectroscopic follow-up to fill in the physical details of newly discovered transients. We are now building a new system intended to ingest and classify transient phenomena in near real-time from high-throughput imaging data streams. Described herein, the Transient Classification Project at Berkeley will be making use of classification techniques operating on"features" extracted from time series and contextual (static) information. We also highlight the need for a community adoption of a standard representation of astronomical time series data (i.e.,"VOTimeseries").
Date: February 22, 2008
Creator: Nugent, Peter E.; Bloom, Josh; Starr, Dan; Butler, Nat; Nugent, Peter; Rischard, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of a CFD Analysis Plan for the first VHTR Standard Problem

Description: Data from a scaled model of a portion of the lower plenum of the helium-cooled very high temperature reactor (VHTR) are under consideration for acceptance as a computational fluid dynamics (CFD) validation data set or standard problem. A CFD analysis will help determine if the scaled model is a suitable geometry for validation data. The present article describes the development of an analysis plan for the CFD model. The plan examines the boundary conditions that should be used, the extent of the computational domain that should be included and which turbulence models need not be examined against the data. Calculations are made for a closely related 2D geometry to address these issues. It was found that a CFD model that includes only the inside of the scaled model in its computational domain is adequate for CFD calculations. The realizable k~e model was found not to be suitable for this problem because it did not predict vortex-shedding.
Date: September 1, 2008
Creator: Johnson, Richard W.
Partner: UNT Libraries Government Documents Department
open access

Object Classification at the Nearby Supernova Factory

Description: We present the results of applying new object classification techniques to the supernova search of the Nearby Supernova Factory. In comparison to simple threshold cuts, more sophisticated methods such as boosted decision trees, random forests, and support vector machines provide dramatically better object discrimination: we reduced the number of nonsupernova candidates by a factor of 10 while increasing our supernova identification efficiency. Methods such as these will be crucial for maintaining a reasonable false positive rate in the automated transient alert pipelines of upcoming large optical surveys.
Date: December 21, 2007
Creator: Aragon, Cecilia R.; Bailey, Stephen; Aragon, Cecilia R.; Romano, Raquel; Thomas, Rollin C.; Weaver, B. A. et al.
Partner: UNT Libraries Government Documents Department
open access

NGNP Data Management and Analysis System Analysis and Web Delivery Capabilities

Description: Projects for the Very High Temperature Reactor Technology Development Office provide data in support of Nuclear Regulatory Commission licensing of the very high temperature reactor. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high-temperature and high-fluence environments. In addition, thermal-hydraulic experiments are conducted to validate codes used to assess reactor safety. The Very High Temperature Reactor Technology Development Office has established the NGNP Data Management and Analysis System (NDMAS) at the Idaho National Laboratory to ensure that very high temperature reactor data are (1) qualified for use, (2) stored in a readily accessible electronic form, and (3) analyzed to extract useful results. This document focuses on the third NDMAS objective. It describes capabilities for displaying the data in meaningful ways and for data analysis to identify useful relationships among the measured quantities.
Date: September 1, 2010
Creator: Gentillon, Cynthia D.
Partner: UNT Libraries Government Documents Department

Archiving and Analysing Elections: How can Web Archiving, Digital Humanities and Political Science go together?

Description: Presentation for the 2019 International Internet Preservation Consortium General Assembly and Web Archiving Conference. This presentation discusses efforts by the Bavarian State Library to understand how web archiving is used as research source material, focusing on a case study on the Bavarian state election by the University of Passau.
Date: June 7, 2019
Creator: Beinert, Tobias; Eckl, Markus; Gassner, Sebastian & Reiter, Florence
Partner: International Internet Preservation Consortium
open access

ATLAS Metadata Task Force

Description: This document provides an overview of the metadata, which are needed to characterizeATLAS event data at different levels (a complete run, data streams within a run, luminosity blocks within a run, individual events).
Date: April 4, 2007
Creator: Collaboration, ATLAS; Costanzo, D.; Cranshaw, J.; Gadomski, S.; Jezequel, S.; Klimentov, A. et al.
Partner: UNT Libraries Government Documents Department

Data Analysis of Early Fuel Cell Market Demonstrations

Description: Presentation about early fuel cell markets, the National Renewable Energy Laboratory's Hydrogen Secure Data Center and its role in data analysis and demonstrations, and composite data products, and results reported to multiple stakeholders.
Date: November 17, 2009
Creator: Kurtz, J.; Ramsden, T.; Wipke, K. & Sprik, S.
Partner: UNT Libraries Government Documents Department
open access

Coupling Visualization and Data Analysis for Knowledge Discovery from Multi-dimensional Scientific Data

Description: Knowledge discovery from large and complex scientific data is a challenging task. With the ability to measure and simulate more processes at increasingly finer spatial and temporal scales, the growing number of data dimensions and data objects presents tremendous challenges for effective data analysis and data exploration methods and tools. The combination and close integration of methods from scientific visualization, information visualization, automated data analysis, and other enabling technologies"such as efficient data management" supports knowledge discovery from multi-dimensional scientific data. This paper surveys two distinct applications in developmental biology and accelerator physics, illustrating the effectiveness of the described approach.
Date: June 8, 2010
Creator: Rubel, Oliver; Ahern, Sean; Bethel, E. Wes; Biggin, Mark D.; Childs, Hank; Cormier-Michel, Estelle et al.
Partner: UNT Libraries Government Documents Department
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