342 Matching Results

Search Results

Advanced search parameters have been applied.

Cross-Shelf Exchange Processes and the Deepwater Circulation of the Gulf of Mexico: Dynamical Effects of Submarine Canyons and the Interactions of Loop Current Eddies with Topography

Description: This report is about the study of interactions of the Gulf of Mexico eddies with topography and the dynamical of submarine canyons in the Gulf of Mexico.
Date: March 2004
Creator: United States. Department of the Interior Minerals Management Service
Partner: UNT Libraries Government Documents Department

Brain topography of leadership: neurophysiological correlates of the leadership opinion questionnaire

Description: Laboratory research was performed to understand leadership by attempting to link EEG baseline frequency patterns with data from the Leadership Opinion Questionnaire (LOQ) assessment survey. Research began with 293 right-handed males, 18-26 years old, who completed the LOQ. Based on their scores, 61 subjects grouped by the Ohio State Leadership Quadrants, were tested using brain-mapping technology.
Date: December 1995
Creator: Dukes, David Jefferson
Partner: UNT Libraries

Topological Landscapes: A Terrain Metaphor for ScientificData

Description: Scientific visualization and illustration tools are designed to help people understand the structure and complexity of scientific data with images that are as informative and intuitive as possible. In this context, the use of metaphors plays an important role, since they make complex information easily accessible by using commonly known concepts. In this paper we propose a new metaphor, called 'Topological Landscapes', which facilitates understanding the topological structure of scalar functions. The basic idea is to construct a terrain with the same topology as a given dataset and to display the terrain as an easily understood representation of the actual input data. In this projection from an n-dimensional scalar function to a two-dimensional (2D) model we preserve function values of critical points, the persistence (function span) of topological features, and one possible additional metric property (in our examples volume). By displaying this topologically equivalent landscape together with the original data we harness the natural human proficiency in understanding terrain topography and make complex topological information easily accessible.
Date: August 1, 2007
Creator: Weber, Gunther H.; Bremer, Peer-Timo & Pascucci, Valerio
Partner: UNT Libraries Government Documents Department

Post-Hoc Analysis of Challenging Behavior by Function: A Comparison of Multiple-Respondent Anecdotal Assessments, Functional Analyses, and Treatments

Description: The current study examines anecdotal assessment, functional analysis, and treatment outcomes from 44 participants. Agreement across Motivation Assessment Scale (MAS), Questions About Behavioral Function (QABF), and Functional Analysis Screening Tool (FAST) assessments, agreement between those anecdotal assessments and functional analyses, and agreement between those anecdotal assessments and treatment outcomes were analyzed across maintaining variables and topography categories of challenging behaviors. Overall, the QABF had the highest agreement results with functional analyses and treatment with 70% and 92% of cases respectively. Patterns in the distribution of maintaining variables was examined across behavior topography categories.
Date: August 2016
Creator: Dignan, Kathleen
Partner: UNT Libraries

Extreme ultraviolet mask substrate surface roughness effects on lithography patterning

Description: In extreme ultraviolet lithography exposure systems, mask substrate roughness induced scatter contributes to LER at the image plane. In this paper, the impact of mask substrate roughness on image plane speckle is explicitly evaluated. A programmed roughness mask was used to study the correlation between mask roughness metrics and wafer plane aerial image inspection. We find that the roughness measurements by top surface topography profile do not provide complete information on the scatter related speckle that leads to LER at the image plane. We suggest at wavelength characterization by imaging and/or scatter measurements into different frequencies as an alternative for a more comprehensive metrology of the mask substrate/multilayer roughness effects.
Date: June 21, 2010
Creator: George, Simi; Naulleau, Patrick; Salmassi, Farhad; Mochi, Iacopo; Gullikson, Eric; Goldberg, Kenneth et al.
Partner: UNT Libraries Government Documents Department

Geology of the Coastal Plain of Georgia

Description: From preface: The manuscript of this report, which is the culmination of field and office studies carried on intermittently s' ice 1914, partly in cooperation with the Geological Survey of Georgia, was completed early in 1938. It was prepared with the expectation that it would form part of a more comprehensive report on the geology of Georgia by several authors, which was intended to accompany a geologic map of the entire State on a scale of 1: 500,000. However, this map without the text was published in 1939 by the Georgia Division of Mines, Mining and Geology. Part of this map is reproduced herein as plate 1 without revision.
Date: 1943
Creator: Cooke, C. Wythe
Partner: UNT Libraries Government Documents Department

Some Engineering Problems of the Panama Canal in Their Relation to Geology and Topography

Description: Report issued by the Bureau of Mines over issues encountered during construction of the Panama Canal. As stated in the introduction, "this report aims to discuss, from the viewpoint of the mining geologist, the bearing of topographic and geologic conditions on certain problems that arose in the construction of the Panama Canal" (p. 7). This report includes tables, maps, illustrations, and photographs.
Date: August 1915
Creator: MacDonald, Donald F.
Partner: UNT Libraries Government Documents Department

Preliminary Report on the Carnotite Deposits of the Old Leyden Coal Mine, Jefferson County, Colorado

Description: From introduction: Mapping, sampling, and radiometric reconnaissance of the uranium-bearing deposits in the Laramie formation in the vicinity of the Old Leyden coal mine, sec. 28, T. 2 S., R. 71 W., Jefferson County, Colorado (fig. 1), was completed August 10, 1951. Topographic and geologic maps were made of areas approximately 6,000 feet by 3,000 feet (scale 1:2h00), and 1,200 feet by 800 feet (scale 1:600). Underground workings at three clay mines and at the Old Leyden mine were also mapped. With the exception of the 1:600 map, which accompanies this report, these maps will be transmitted later with a more comprehensive report.
Date: September 1951
Creator: McKeown, Frank A. & Gude, James
Partner: UNT Libraries Government Documents Department

MRF Applications: On the Road to Making Large-Aperture Ultraviolet Laser Resistant Continuous Phase Plates for High-Power Lasers

Description: Over the past two years we have developed MRF tools and procedures to manufacture large-aperture (430 X 430 mm) continuous phase plates (CPPs) that are capable of operating in the infrared portion (1053 nm) of high-power laser systems. This is accomplished by polishing prescribed patterns of continuously varying topographical features onto finished plano optics using MRF imprinting techniques. We have been successful in making, testing, and using large-aperture CPPs whose topography possesses spatial periods as low as 4 mm and surface peak-to-valleys as high as 8.6 {micro}m. Combining this application of MRF technology with advanced MRF finishing techniques that focus on ultraviolet laser damage resistance makes it potentially feasible to manufacture large-aperture CPPs that can operate in the ultraviolet (351 nm) without sustaining laser-induced damage. In this paper, we will discuss the CPP manufacturing process and the results of 351-nm/3-nsec equivalent laser performance experiments conducted on large-aperture CPPs manufactured using advanced MRF protocols.
Date: October 26, 2006
Creator: Menapace, J A; Davis, P J; Steele, W A; Hachkowski, M R; Nelson, A & Xin, K
Partner: UNT Libraries Government Documents Department

Carbon contamination topography analysis of EUV masks

Description: The impact of carbon contamination on extreme ultraviolet (EUV) masks is significant due to throughput loss and potential effects on imaging performance. Current carbon contamination research primarily focuses on the lifetime of the multilayer surfaces, determined by reflectivity loss and reduced throughput in EUV exposure tools. However, contamination on patterned EUV masks can cause additional effects on absorbing features and the printed images, as well as impacting the efficiency of cleaning process. In this work, several different techniques were used to determine possible contamination topography. Lithographic simulations were also performed and the results compared with the experimental data.
Date: March 12, 2010
Creator: Fan, Y.-J.; Yankulin, L.; Thomas, P.; Mbanaso, C.; Antohe, A.; Garg, R. et al.
Partner: UNT Libraries Government Documents Department

Structural Characterization of Doped GaSb Single Crystals by X-ray Topography

Description: We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with the findings predicted by the dynamical theory of x-ray diffraction. These measurements show that our GaSb single crystals have a relative variation in the lattice parameter ({Delta}d/d) on the order of 10{sup -5}. This means that they can be used as electronic devices (detectors, for example) and as x-ray monochromators.
Date: September 13, 2009
Creator: Honnicke, M.G.; Mazzaro, I.; Manica, J.; Benine, E.; M da Costa, E.; Dedavid, B. A. et al.
Partner: UNT Libraries Government Documents Department

Carbon contamination of extreme ultraviolet (EUV) mask and its effect on imaging

Description: Carbon contamination of extreme ultraviolet (EUV) masks and its effect on imaging is a significant issue due to lowered throughput and potential effects on imaging performance. In this work, a series of carbon contamination experiments were performed on a patterned EUV mask. Contaminated features were then inspected with a reticle scanning electron microscope (SEM) and printed with the SEMA TECH Berkeley Microfield-Exposure tool (MET) [1]. In addition, the mask was analyzed using the SEMA TECH Berkeley Actinic-Inspection tool (AIT) [2] to determine the effect of carbon contamination on the absorbing features and printing performance. To understand the contamination topography, simulations were performed based on calculated aerial images and resist parameters. With the knowledge of the topography, simulations were then used to predict the effect of other thicknesses of the contamination layer, as well as the imaging performance on printed features.
Date: February 2, 2009
Creator: Fan, Yu-Jen; Yankulin, Leonid; Antohe, Alin; Garg, Rashi; Thomas, Petros; Mbanaso, Chimaobi et al.
Partner: UNT Libraries Government Documents Department

Thorough characterization of a EUV mask

Description: We reported that we were successful in our 45nm technology node device demonstration in February 2008 and 22nm node technology node device patterning in February 2009 using ASML's Alpha Demo Tool (ADT). In order to insert extreme ultraviolet (EUV) lithography at the 15nm technology node and beyond, we have thoroughly characterized one EUV mask, a so-called NOVACD mask. In this paper, we report on three topics, The first topic is an analysis of line edge roughness (LER) using a mask Scanning Electron Microscope (SEM), an Atomic Force Microscope (AFM) and the Actinic Inspection Tool (AIT) to compare resist images printed with the ASML ADT. The results of the analysis show a good correlation between the mask AFM and the mask SEM measurements, However, the resist printing results for the isolated space patterns are slightly different. The cause ofthis discrepancy may be resist blur, image log slope and SEM image quality and so on. The second topic is an analysis of mask topography using an AFM and relative reflectivity of mirror and absorber surface using the AIT, The AFM data show 6 and 7 angstrom rms roughness for mirror and absorber, respectively. The reflectivity measurements show that the mirror reflects EUV light about 20 times higher than absorber. The last topic is an analysis of a 32nm technology node SRAM cell which includes a comparison of mask SEM image, AIT image, resist image and simulation results. The ADT images of the SRAM pattern were of high quality even though the mask patters were not corrected for OPC or any EUV-specific effects. Image simulation results were in good agreement with the printing results.
Date: June 25, 2009
Creator: Mizuno, H.; McIntyre, G.; Koay, C.-W.; Burkhardt, M.; He, L.; Hartley, J. et al.
Partner: UNT Libraries Government Documents Department

Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites

Description: Understanding the potential impacts of unexpected surface releases of CO{sub 2} is an essential part of risk assessment for geologic carbon sequestration sites. We have extended a mesoscale atmospheric model to model dense gas dispersion of CO{sub 2} leakage. The hazard from CO{sub 2} leakage is greatest in regions with topographic depressions where the dense gas can pool. Simulation of dispersion in idealized topographies shows that CO{sub 2} can persist even under high winds. Simulation of a variety of topographies, winds, and release conditions allows the generation of a catalog of simulation results that can be queried to estimate potential impacts at actual geologic carbon sequestration sites.
Date: November 1, 2008
Creator: Chow, Fotini K.; Granvold, Patrick W. & Oldenburg, Curtis M.
Partner: UNT Libraries Government Documents Department

Scale Interaction in a California precipitation event

Description: Heavy rains and severe flooding frequently plaque California. The heavy rains are most often associated with large scale cyclonic and frontal systems, where large scale dynamics and large moisture influx from the tropical Pacific interact. however, the complex topography along the west coast also interacts with the large scale influences, producing local areas with heavier precipitation. In this paper, we look at some of the local interactions with the large scale.
Date: September 1, 1997
Creator: Leach, M. J., LLNL
Partner: UNT Libraries Government Documents Department

A Combined Experimental and Computational Approach for the Design of Mold Topography that Leads to Desired Ingot Surface and Microstructure in Aluminum Casting.

Description: A thermomechanical study of the effects of mold topography on the solidification of Aluminum alloys at early times is provided. The various coupling mechanisms between the solid-shell and mold deformation and heat transfer at the mold/solid-shell interface during the early stages of Aluminum solidification on molds with uneven topographies are investigated. The air-gap nucleation time, the stress evolution and the solid-shell growth pattern are examined for different mold topographies to illustrate the potential control of Aluminum cast surface morphologies during the early stages of solidification using proper design of mold topographies. The unstable shell growth pattern in the early solidification stages results mainly from the unevenness of the heat flux between the solid-shell and the mold surface. This heat flux is determined by the size of the air-gaps formed between the solidifying shell and mold surface or from the value of the contact pressure. Simulation results show that a sinusoidal mold surface with a smaller wavelength leads to nucleation of air-gaps at earlier times. In addition, the unevenness in the solid-shell growth pattern decreases faster for a smaller wavelength. Such studies can be used to tune mold surfaces for the control of cast surface morphologies.
Date: July 12, 2005
Creator: Dr. Zabaras, N. & Tan, L.
Partner: UNT Libraries Government Documents Department