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1998

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Neural Network Modeling Of The Head-Related Transfer Function, Damion Reinhardt Mar 1998

Neural Network Modeling Of The Head-Related Transfer Function, Damion Reinhardt

Theses and Dissertations

Battlefield synthesis of 3-D audio may require the interpolation and compression of head-related transfer function (HRTF) data. This thesis is an implementation of a functional model of the HRTF using artificial neural networks (ANNs), the model provides both compression and interpolation.

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Analyzing Horizontal Distances Between Wsr-88d Thunderstorm Centroids And Cloud-To-Ground Lightning Strikes, Steve L. Renner Mar 1998

Analyzing Horizontal Distances Between Wsr-88d Thunderstorm Centroids And Cloud-To-Ground Lightning Strikes, Steve L. Renner

Theses and Dissertations

On April 29, 1996, lightning struck the airfield at Hurlburt Field, FL, killing one Airmen and injuring ten others. This cloud to ground lightning strike hit eight minutes after a lightning advisory was canceled. At the time of the strike, thunderstorms were observed 7 to 10 miles north and south of the airfield. The incident raised questions about Air Force Weather Agency's lightning criteria. Soon after the incident, a Lightning Safety Review Panel was assembled to determine the adequacy of lightning advisories. One of the questions posed to the panel was could an incident like Hurlburt happen again? The review …

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A Validation Study Of The Air Force Weather Agency (Afwa) Jetrax Contrail Forecast Algorithm, Jeffrey D. Shull Mar 1998

A Validation Study Of The Air Force Weather Agency (Afwa) Jetrax Contrail Forecast Algorithm, Jeffrey D. Shull

Theses and Dissertations

Accurate contrail forecasts allow pilots to avoid levels of the atmosphere which are conducive to contrail formation, reducing their likelihood of being visually detected by enemy forces. The primary objective of this thesis is to evaluate the performance of the JETRAX contrail forecast algorithm currently used by the Air Force Weather Agency to support military air operations. A total of 397 ground-based contrail observations were collected at Wright-Patterson Air Force Base on 27 different days. Observations were collected with the aid of air traffic control radar, which greatly facilitated the positive identification of overflying aircraft and provided necessary information such …

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Analysis Of Alternatives: Multivariate Considerations, John J. Siegner Mar 1998

Analysis Of Alternatives: Multivariate Considerations, John J. Siegner

Theses and Dissertations

The Aeronautical System Center (ASC) is developing a Simulation and Analysis Facility (SIMAF) that will link models, simulations, hardware-in-the-loop, and system-in-the-loop resources to create a robust virtual environment supporting assessment of alternate systems in the defense acquisition process. ENS is assisting ASC with scenario development, experimental design, and battleroom visualization efforts for a SIMAF capability demonstration. This thesis uses multivariate analysis and visualization tools to develop an approach for reducing the dimensionality of multiple campaign level measures of effectiveness for a notional Analysis of Alternatives (AoA) study. Additionally, the thesis advances an AoA visualization paradigm for the SIMAF capability demonstration. …

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The Application Of Sequential Convex Programming To Large-Scale Structural Optimization Problems, Todd A. Sriver Mar 1998

The Application Of Sequential Convex Programming To Large-Scale Structural Optimization Problems, Todd A. Sriver

Theses and Dissertations

Structural design problems are often modeled using finite element methods. Such models are often characterized by constraint functions that are not explicitly defined in terms of the design variables. These functions are typically evaluated through numerical finite element analysis (FEA). Optimizing large-scale structural design models requires computationally expensive FEAs to obtain function and gradient values. An optimization approach which uses the SCP sequential convex programming algorithm of Zillober, integrated as the optimizer in the Automated Structural Optimization System (ASTROS), is tested. The traditional approach forms an explicitly defined approximate subproblem at each design iteration that is solved using the method …

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Improving Cape Canaveral's Day-2 Thunderstorm Forecasting Using Meso-Eta Numerical Model Output, Christian S. Wohlwend Mar 1998

Improving Cape Canaveral's Day-2 Thunderstorm Forecasting Using Meso-Eta Numerical Model Output, Christian S. Wohlwend

Theses and Dissertations

The 45th Weather Squadron (WS) is responsible for the protection of billions of dollars worth of Air Force and NASA equipment from weather hazards. They produce a seven day planning forecast as one tool to support the space launch community. Improving this forecast can potentially save millions of dollars of government funds. This research focuses on the feasibility of improving the day two thunderstorm forecast by applying Meso Eta numerical forecasts to the Neumann-Pfeffer Thunderstorm Index (NPTI). The NPTI is currently used by the 45th WS for same day thunderstorm probability forecasting utilizing the morning radiosonde as input. The perfect …

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Multiple Model Adaptive Estimation Using Filter Spawning, Kenneth A. Fisher Mar 1998

Multiple Model Adaptive Estimation Using Filter Spawning, Kenneth A. Fisher

Theses and Dissertations

Multiple Model Adaptive Estimation with Filter Spawning is used to detect and estimate partial actuator failures on the VISTA F-16. The truth model is a full six-degree-of-freedom simulation provided by Calspan and General Dynamics. The design models are chosen as 13-state linearized models, including first order actuator models. Actuator failures are incorporated into the truth model and design model assuming a "failure to free stream . Filter Spawning is used to include additional filters with partial actuator failure hypotheses into the Multiple Model Adaptive Estimation (MMAE) bank. The spawned filters are based on varying degrees of partial failures (in terms …

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Observations On Palearctic Waders Wintering In The Inner Niger Delta Of Mali, R. Tinarelli Mar 1998

Observations On Palearctic Waders Wintering In The Inner Niger Delta Of Mali, R. Tinarelli

International Wader Studies

No abstract provided.

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Lemming Density In Taimyr Tundra And Its Influence On Reproduction Of Birds, A. V. Rybkin Mar 1998

Lemming Density In Taimyr Tundra And Its Influence On Reproduction Of Birds, A. V. Rybkin

International Wader Studies

No abstract provided.

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Between-Year Recapture Rates Of Waders Ringed On Migration In South-Eastern Kazakhstan: Constancy In Timing And Location Of Flyway Routes, E. I. Gavrilov, S. N. Erokhov, A. E. Gavrilov Mar 1998

Between-Year Recapture Rates Of Waders Ringed On Migration In South-Eastern Kazakhstan: Constancy In Timing And Location Of Flyway Routes, E. I. Gavrilov, S. N. Erokhov, A. E. Gavrilov

International Wader Studies

No abstract provided.

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Interfacing African American Churches With Agencies And Institutions: An Expanding Continuum Of Care With Partial Answers To Welfare Reform, Barbara W. Rogers, Douglas Ronsheim Mar 1998

Interfacing African American Churches With Agencies And Institutions: An Expanding Continuum Of Care With Partial Answers To Welfare Reform, Barbara W. Rogers, Douglas Ronsheim

The Journal of Sociology & Social Welfare

It is unrealistic to presume that churches and other private charities can fill the void resulting from welfare reform (Sider,1995; Conniff, 1997); yet there are ways to structure an effective church- and community-based continuum of care that will help to do so. In this article African-American churches are viewed as major players. An explanation of the systems theory of isomorphic replication provides a key to understanding the success of this collaborative model, which addresses issues facing communities while building on their strengths and assets and reckoning with the challenges of working collaboratively. Recurring issues of race, culture, trust, and control …

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Experimental Evolution Of Complexity: In Vitro Emergence Of Intermolecular Ribozyme Interactions, Martin M. Hanczyc, Robert L. Dorit Mar 1998

Experimental Evolution Of Complexity: In Vitro Emergence Of Intermolecular Ribozyme Interactions, Martin M. Hanczyc, Robert L. Dorit

Biological Sciences: Faculty Publications

In the course of evolving variants of the Tetrahymena thermophila Group I ribozyme for improved DNA cleavage in vitro, we witnessed the unexpected emergence of a derived molecular species, capable of acting as a partner for the ribozyme, but no longer autocatalytic. This new RNA species exhibits a deletion in the catalytic core and participates in a productive intermolecular interaction with an active ribozyme, thus insuring its survival in the population. These novel RNA molecules have evolved a precise catalytic interaction with the Group I ribozyme and depend for their survival on the continued presence of active catalysts. This interaction …

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Cryptococcus Neoformans Chemotyping By Quantitative Analysis Of H-1 Nuclear Magnetic Resonance Spectra Of Glucuronoxylomannans With A Computer-Simulated Artificial Neural Network, Robert Cherniak, Homayoun Valafar, Laura C. Morris, Faramarz Valafar Mar 1998

Cryptococcus Neoformans Chemotyping By Quantitative Analysis Of H-1 Nuclear Magnetic Resonance Spectra Of Glucuronoxylomannans With A Computer-Simulated Artificial Neural Network, Robert Cherniak, Homayoun Valafar, Laura C. Morris, Faramarz Valafar

Faculty Publications

The complete assignment of the proton chemical shifts obtained by nuclear magnetic resonance (NMR) spectroscopy of de-O-acetylated glucuronoxylomannans (GXMs) from Cryptococcus neoformanspermitted the high-resolution determination of the total structure of any GXM. Six structural motifs based on an α-(1→3)-mannotriose substituted with variable quantities of 2-O-β- and 4-O-β-xylopyranosyl and 2-O-β-glucopyranosyluronic acid were identified. The chemical shifts of only the anomeric protons of the mannosyl residues served as structure reporter groups (SRG) for the identification and quantitation of the six triads present in any GXM. The assigned protons for the mannosyl residues resonated at clearly …

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University Reporter - Vol. 02, No. 07 - March 1998, University Of Massachusetts Boston Mar 1998

University Reporter - Vol. 02, No. 07 - March 1998, University Of Massachusetts Boston

1996-2009, University Reporter

No abstract provided.

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Women's Studies Program Newsletter, Spring 1998, University Of Montana--Missoula. Department Of Women's Studies Mar 1998

Women's Studies Program Newsletter, Spring 1998, University Of Montana--Missoula. Department Of Women's Studies

Women’s Studies Newsletter, 1993-2003

Newsletter published by the University of Montana Women's Studies Program (now the Women’s, Gender and Sexuality Studies Department).

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Double Photoionization Of Helium, James A.R. Samson, Wayne C. Stolte, Z. X. He, Y. Lu, J. N. Cutler, R. J. Bartlett Mar 1998

Double Photoionization Of Helium, James A.R. Samson, Wayne C. Stolte, Z. X. He, Y. Lu, J. N. Cutler, R. J. Bartlett

Chemistry and Biochemistry Faculty Research

The cross sections for double photoionization of helium and the ratios of double to single ionization have been measured from the double-ionization threshold to 820 eV. The results are in very good agreement with several recent calculations.

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Equality: A Comparison Of Three Countries, Ronald C. Griffin Mar 1998

Equality: A Comparison Of Three Countries, Ronald C. Griffin

Journal Publications

No abstract provided.

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A Case Study Of The Factors Involved In Enhancing A Positive Learning Environment In A Native American School In Nebraska, Henry Eggert Mar 1998

A Case Study Of The Factors Involved In Enhancing A Positive Learning Environment In A Native American School In Nebraska, Henry Eggert

Student Work

The purpose of this study is to investigate factors involved in enhancing a positive learning environment in a Native American school. The study will address the factors involved in enhancing a positive learning environment as perceived by K-12 teachers of Native American Students.

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Table Of Contents Volume Nine, Number Two, Spring 1998, Risk Editorial Board Mar 1998

Table Of Contents Volume Nine, Number Two, Spring 1998, Risk Editorial Board

RISK: Health, Safety & Environment (1990-2002)

Table of contents for the journal RISK: Health, Safety & Environment (ISSN: 1073-8673)

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Through A Lens Darkly--Superfund Spectacles On Public Participation At Brownfield Sites, Kris Wernstedt, Robert Hersh Mar 1998

Through A Lens Darkly--Superfund Spectacles On Public Participation At Brownfield Sites, Kris Wernstedt, Robert Hersh

RISK: Health, Safety & Environment (1990-2002)

The authors discuss the recent trend in brownfield site development against a backdrop of Superfund experience and explore current barriers to public participation.

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Involving Others: Towards An Ethical Concept Of Risk, Christoph Rehmann-Sutter Mar 1998

Involving Others: Towards An Ethical Concept Of Risk, Christoph Rehmann-Sutter

RISK: Health, Safety & Environment (1990-2002)

Dr. Rehman-Sutter argues for a juridical concept of risk as it relates to an ethic of care. He also contrasts his view with traditional economic risk analysis.

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A Longitudinal Study Of Hospitalization Rates For Patients With Chronic Disease: Results From The Medical Outcomes Study., Eugene C. Nelson, Colleen A. Mchorney, Willard G. Manning, W H. Rogers Mar 1998

A Longitudinal Study Of Hospitalization Rates For Patients With Chronic Disease: Results From The Medical Outcomes Study., Eugene C. Nelson, Colleen A. Mchorney, Willard G. Manning, W H. Rogers

Dartmouth Scholarship

To prospectively compare inpatient and outpatient utilization rates between prepaid (PPD) and fee-for-service (FFS) insurance coverage for patients with chronic disease. Data from the Medical Outcomes Study, a longitudinal observational study of chronic disease patients conducted in Boston, Chicago, and Los Angeles.A four-year prospective study of resource utilization among 1,681 patients under treatment for hypertension, diabetes, myocardial infarction, or congestive heart failure in the practices of 367 clinicians.

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The Warps Survey. Ii. The Log N –Log S Relation And The X‐Ray Evolution Of Low‐Luminosity Clusters Of Galaxies, L. R. Jones, C. Scharf, H. Ebeling, E. Perlman, G. Wegner, M. Malkan, D. Horner Mar 1998

The Warps Survey. Ii. The Log N –Log S Relation And The X‐Ray Evolution Of Low‐Luminosity Clusters Of Galaxies, L. R. Jones, C. Scharf, H. Ebeling, E. Perlman, G. Wegner, M. Malkan, D. Horner

Dartmouth Scholarship

The strong negative evolution observed in previous X-ray-selected surveys of clusters of galaxies is evidence in favor of hierarchical models of the growth of structure in the universe. A large recent survey has, however, contradicted the low-redshift results, finding no evidence for evolution at z < 0.3. Here we present the first results from an X-ray-selected, flux- and surface brightness-limited deep survey for high-redshift clusters and groups of galaxies based on ROSAT PSPC pointed data. The log N-log S relation of all clusters in this survey is consistent with that of most previous surveys, but it occupies a flux range not previously covered (greater than 6 × 10-14 ergs cm-2 s-1 total flux in the 0.5-2 keV band). At high redshifts ( …

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A Late-Time Optical Detection Of Sn 1985l In Ngc 5033, Robert A. Fesen Mar 1998

A Late-Time Optical Detection Of Sn 1985l In Ngc 5033, Robert A. Fesen

Dartmouth Scholarship

An apparent late-time optical recovery of SN 1985L (Type II-L) in the Sb galaxy NGC 5033 is presented and discussed. An Hα emission point source is found within 1'' of both SN 1985L's historically reported position 70'' west and 55'' north of NGC 5033's center and its late-time, radio-measured position. This Hα source is not visible on V-band or narrow red continuum (7000 ± 125 Å) images, but is detected using a 6510 Å filter (FWHM = 30 Å). Its detection at 6510 Å can be attributed to blueshifted Hα emission because of a broad (±5000 km s-1 …

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Faculty Senate Monthly Packet March 1998, Portland State University Faculty Senate Mar 1998

Faculty Senate Monthly Packet March 1998, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The March 1998 Monthly packet includes the March agenda and appendices and the Faculty Senate minutes and attachments from the meeting held February 1998.

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Identifying And Valuing The Injury In Lost Chance Cases, Todd S. Aagaard Mar 1998

Identifying And Valuing The Injury In Lost Chance Cases, Todd S. Aagaard

Michigan Law Review

Any plaintiff seeking to recover in tort must prove that the defendant has breached the duty of care. Even after the plaintiff has established the defendant's breach of duty, however, issues of causation and damages remain. These two issues are frequently vexing, both conceptually and in terms of evidentiary demonstration. For example, if a plaintiff proves that a defendant acted negligently, it still may be unclear whether the plaintiff would have been injured even ip the absence of the defendant's negligence. Similarly, in assessing damages, factfinders often :find it difficult to attach a monetary value to a plaintiff's nonpecuniary losses …

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Plain Meaning, Practical Reason, And Cuplability: Toward A Theory Of Jury Interpretation Of Criminal Statutes, Darryl K. Brown Mar 1998

Plain Meaning, Practical Reason, And Cuplability: Toward A Theory Of Jury Interpretation Of Criminal Statutes, Darryl K. Brown

Michigan Law Review

In one of the few existing recordings of American juries deliberating in an actual criminal case, Wisconsin v. Reed, we observe jurors struggling with how they should apply a statute in a case in which the facts are not in real dispute. The defendant is charged with felon in possession of a gun, and all agree that he has a felony record and owned a pistol until he turned it over to the police upon their request. The statute contains three elements. The defendant must (a) have a felony conviction, (b) have possessed a gun, and (c) have known that …

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Sharp, Quantitative Bounds On The Distance Between A Bezier Curve And Its Control Polygon, D. Nairn, J. Peters, D. Lutterkort Mar 1998

Sharp, Quantitative Bounds On The Distance Between A Bezier Curve And Its Control Polygon, D. Nairn, J. Peters, D. Lutterkort

Department of Computer Science Technical Reports

No abstract provided.

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Message Patterns In The Bond Distributed Object System, Ladislau Bölöni, Kyung-Koo Jun, Thomas Danials, Dan C. Marinescu Mar 1998

Message Patterns In The Bond Distributed Object System, Ladislau Bölöni, Kyung-Koo Jun, Thomas Danials, Dan C. Marinescu

Department of Computer Science Technical Reports

No abstract provided.

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Long-Run Simulations With Gtap: Illustrative Results From Apec Trade Liberalisation, Terrie Walmsley Mar 1998

Long-Run Simulations With Gtap: Illustrative Results From Apec Trade Liberalisation, Terrie Walmsley

GTAP Technical Papers Archive

In static applied general equilibrium models, the exogenous/endogenous split between variables (or closure) is used to infer the time frame over which the effects of a shock are simulated. This paper introduces a long-run closure for the GTAP model (Hertel and Tsigas, 1997) and uses this closure to simulate and compare the short-run and long-run effects of Asia-Pacific trade liberalisation. The approach explored here incorporates some relatively minor changes to existing GTAP theory in order to define a steady state in which growth rates of all real variables are uniform. Such uniformity must apply in the initial database (as well …

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