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Astronaut Eva Exposure Estimates From Cad Model Spacesuit Geometry, Giovanni De Angelis, Brooke M. Anderson, William Atwell, John E. Nealy, Gary D. Qualls, John W. Wilson Mar 2004

Astronaut Eva Exposure Estimates From Cad Model Spacesuit Geometry, Giovanni De Angelis, Brooke M. Anderson, William Atwell, John E. Nealy, Gary D. Qualls, John W. Wilson

Mathematics & Statistics Faculty Publications

Ongoing assembly and maintenance activities at the International Space Station (ISS) require much more extravehicular activity (EVA) than did the earlier U.S. Space Shuttle missions. It is thus desirable to determine and analyze, and possibly foresee, as accurately as possible what radiation exposures crew members involved in EVAs will experience in order to minimize risks and to establish exposure limits that must not to be exceeded. A detailed CAD model of the U.S. Space Shuttle EVA Spacesuit, developed at NASA Langley Research Center (LaRC), is used to represent the directional shielding of an astronaut; it has detailed helmet and backpack …


Experimental And Computational Analysis Of Modes In A Partially Constrained Plate, Robert M. Vandawaker Mar 2004

Experimental And Computational Analysis Of Modes In A Partially Constrained Plate, Robert M. Vandawaker

Theses and Dissertations

The field of structural health monitoring (SHM) attempts to reduce labor and cost by allowing technicians to monitor selected properties of an aircraft's structure to detect impending failure. This research examines methods to detect damage to a thermal protection system (TPS) tile using representative 2024-T3 aluminum plates. Plates are subjected to modal analysis in single and joined conditions in an attempt to provide the capability of sensing damage to a tile on the surface of a vehicle while the sensors remain on the superstructure of the airframe. Jointly, the development of a means to model the system using finite element …


Vibrometric Detection Of Beam Damage Due To Inclusions, Aaron J. Reifsnyder Mar 2004

Vibrometric Detection Of Beam Damage Due To Inclusions, Aaron J. Reifsnyder

Theses and Dissertations

The Air Force Institute of Technology, in conjunction with the Structural Health Monitoring branch of the Air Force Research Laboratory, is researching methods of determining effects of notch location and size on beam structures using modal frequency analysis. This thesis explores the ability to detect included notches of varying magnitudes and locations within the frequency domain of an isotropic cantilever beam. A series of experiments employing centerline-notched 2024 T3 and 2024 0 aluminum beams was used to determine whether natural frequency measurement in beam structures is a valid mechanism for damage detection. Each specimen was excited by a strain actuator …


A Demand Side Requirements Model To Forecast C-17 Mobility Aircraft Availability, Joseph R. Huscroft Jr. Mar 2004

A Demand Side Requirements Model To Forecast C-17 Mobility Aircraft Availability, Joseph R. Huscroft Jr.

Theses and Dissertations

Current aircraft forecasting methods of the Air Mobility Command (AMC) Directorate of Logistics are reliant on the experience of personnel and lead to after the fact, labor-intensive analysis. These deficiencies led AMC to the development of a Mobility Aircraft Availability Forecasting (MAAF) model. The purpose of the MAAF model is threefold: predict aircraft availability in order to provide the Tanker Airlift Control Center (TACC) with a forecast of aircraft that will be available for AMC mission requirements, provide what if capabilities that analyze the effects of tasking and policy changes, and to provide foresight into problems associated with aircraft availability …


Reusable Space Vehicle Ground Operations Baseline Conceptual Model, Dennis R. Maynard, Patricia Pettit Mar 2004

Reusable Space Vehicle Ground Operations Baseline Conceptual Model, Dennis R. Maynard, Patricia Pettit

Theses and Dissertations

Modeling efforts for future space operation vehicles at the United States Air Force Research Labs Air Vehicles Directorate have been focused towards the in-flight mission. To better serve the research and development effort, a simulation of the ground operations is required allowing for trade-offs within turnaround operations and between the components that drive those procedures. However, before a simulation can be developed a conceptual model must be generated to guide the model building process. This research provides a baseline conceptual model for reusable space vehicles based on the space shuttle as the only operational vehicle of its kind. The model …


Measuring The Risk Of Shortfalls In Air Force Capabilities, William E. Woodward Mar 2004

Measuring The Risk Of Shortfalls In Air Force Capabilities, William E. Woodward

Theses and Dissertations

The U.S. Air Force seeks to measure and prioritize risk as part of its Capabilities Review and Risk Assessment (CRRA) process. The goal of the CRRA is to identify capability shortfalls, and the risks associated with those shortfalls, to influence future systems acquisition. Many fields, including engineering, medicine and finance, seek to model and measure risks. This research utilizes various risk measurement approaches to propose appropriate risk measures for a military context. Specifically, risk is modeled as a non-negative random variable of severity. Four measures are examined: simple expectation, a risk-value measure, tail conditional expectation, and distorted expectation. Risk measures …


Developing Team Cohesion: A Quasi-Field Experiment, John F. Costello Mar 2004

Developing Team Cohesion: A Quasi-Field Experiment, John F. Costello

Theses and Dissertations

Within military organizations, research findings have lent support to the positive influence cohesion has on group performance in combat and non-combat areas, Beyond performance, research findings show that cohesion influences the job satisfaction, and health of military members, particularly under highly stressful conditions, such as those encountered in combat or extended deployments. The purpose of this research effort is to further analyze the strategies that should be used to develop cohesiveness among Air Force members. This was done by testing the extent to which cohesion changed when familiarization and challenging situations were coupled in a technical training course geared towards …


Characterization Of Microbial Processes That Degrade Chlorinated Solvents In A Constructed Wetland Using Organic Acid And Inorganic Anion Concentration Profiles, Chad B. Bondurant Mar 2004

Characterization Of Microbial Processes That Degrade Chlorinated Solvents In A Constructed Wetland Using Organic Acid And Inorganic Anion Concentration Profiles, Chad B. Bondurant

Theses and Dissertations

Chlorinated solvents have been used in industrial cleaning and degreasing processes in the United States since the early 1900s, and their induction into the environment increased significantly with the growth of industrial processes over the past century. PCE, TCE and their daughter products have been associated with a number of human health concerns and are currently the most common contaminants found in groundwater in the United States. Wetlands possess characteristics necessary for the complete degradation of chlorinated ethenes by microorganisms via anaerobic and aerobic regions that foster the necessary oxidation-reduction conditions. Organic acid and inorganic anion concentrations were evaluated in …


Modeling A Field Application Of In Situ Bioremediation Of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells (Hftws), Peter G. Chosa Mar 2004

Modeling A Field Application Of In Situ Bioremediation Of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells (Hftws), Peter G. Chosa

Theses and Dissertations

Perchlorate contaminated groundwater is rapidly becoming a significant environmental remediation issue for the Department of Defense. In this study, an existing numerical model that simulates the operation of a Horizontal Flow Treatment Well (HFTW) system to effect the in situ biodegradation of perchlorate through the addition of an electron donor is modified to include a submodel that describes bioclogging. Bioclogging restricts flow out of the HFTW due to the accumulation of biomass directly adjacent to the well. The modified model is then applied to an existing perchlorate contaminated site that will be used for an evaluation of the HFTW technology. …


Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Mtbe-Contaminated Groundwater, Preston F. Rufe Mar 2004

Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Mtbe-Contaminated Groundwater, Preston F. Rufe

Theses and Dissertations

This study utilized a three-dimensional numerical model to evaluate the potential application of HFTWs to manage MTBE-contaminated groundwater. HFTWs consist of two dual-screened treatment wells. One well operates in an upflow mode, with MTBE-contaminated water extracted from an aquifer through a screen in the deep portion of an aquifer and injected into the aquifer through a shallow well screen, while the adjacent well operates in a downflow mode, extracting water from the shallow zone of the aquifer and injecting it into the deep zone. As the MTBE-contaminated water flows through the wells, an electron acceptor and/or another electron donor is …


Bs News Mar 2004

Bs News

Building Services Engineering

No abstract provided.


Making Learning Visible: Peer Review And The Scholarship Of Teaching, Paul Savory Mar 2004

Making Learning Visible: Peer Review And The Scholarship Of Teaching, Paul Savory

Department of Industrial and Management Systems Engineering: Presentations

This is the conference program from the March 2004 national conference, Making Learning Visible: Peer Review and the Scholarship of Teaching. This conference was hosted by the UNL Peer Review of Teaching project and the University of Nebraska-Lincoln.


Afci Quarterly Input – Unlv January Through March, 2004, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division Mar 2004

Afci Quarterly Input – Unlv January Through March, 2004, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

Quarterly report highlighting research projects and objectives of the Transmutation Research Program at the Nuclear Science & Technology Division, Harry Reid Research Center.

The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.


Inside Unlv, Gian Galassi, Carol C. Harter, Kenneth E. Marks Mar 2004

Inside Unlv, Gian Galassi, Carol C. Harter, Kenneth E. Marks

Inside UNLV

No abstract provided.


Analysis And Forecasting Of Army Operating And Support Cost For Rotary Aircraft, John C. Hawkins Mar 2004

Analysis And Forecasting Of Army Operating And Support Cost For Rotary Aircraft, John C. Hawkins

Theses and Dissertations

This research explores forecasting techniques to estimate the Cost per Flying Hour (CPFH) for Army Helicopters. Specifically, three separate forecasting techniques were evaluated to better predict the CPFH for better estimating and budgeting by the U.S. Army. For forecasting purposes, actual CPFH figures were compiled from 1995 to 2003 for all MACOMs flying the AH-64A, the CH-47D, and the UH-60A helicopters. The number of MACOMs was then reduced to the top three with regard to total CPFH expenditure. The use of a 3-year moving average, the single exponential smoothing method, and Holt's linear method were explored for each helicopter's data. …


Analysis And Forecasting Of Air Force Operating And Support Cost For Rotary Aircraft, Matthew E. Laubacher Mar 2004

Analysis And Forecasting Of Air Force Operating And Support Cost For Rotary Aircraft, Matthew E. Laubacher

Theses and Dissertations

This research explores forecasting techniques to estimate the Cost per Flying Hour (CPFH) for Air Force Helicopters. Specifically, this research evaluates three separate forecasting techniques to predict the CPFH for better estimating and budgeting by the U.S. Air Force. It starts by empirically analyzing the Operating and Support cost by CAIG categories for each helicopter. For forecasting purposes, the actual CPFH figures were compiled from FY96 to FY03 for a total of eight MAJCOMs flying the MH-53J/M, the HH-60G, or the UH-1N helicopters. The research explores the use of a 3-year moving average, the single exponential smoothing method, and Holt's …


Effects Of Duty Schedule Variance And Overtime On The Job Satisfaction And Turnover Intentions Of Usaf F-16 Crew Chiefs, Michael J. Shellhamer Mar 2004

Effects Of Duty Schedule Variance And Overtime On The Job Satisfaction And Turnover Intentions Of Usaf F-16 Crew Chiefs, Michael J. Shellhamer

Theses and Dissertations

This thesis empirically assessed how duty schedule variance and overtime affect the job satisfaction and turnover intentions of USAF F-16 crew chiefs. A survey was completed by 346 active duty USAF F-16 crew chiefs regarding their perceptions of duty schedule variance, overtime, job satisfaction and intent to leave the Air Force. Theory suggests that turnover behavior is a multistage process that involves organizational, individual, and attitudinal components. Using multivariate correlation and regression analyses, plausible evidence was found to support the idea that duty schedule variance and overtime plays a role in USAF F-16 crew chief turnover intentions via job satisfaction. …


Cross-Service Investigation Of Geographical Information Systems, Matthew H. Beverly Mar 2004

Cross-Service Investigation Of Geographical Information Systems, Matthew H. Beverly

Theses and Dissertations

This research investigated the armed services current uses of GIS, and asked the question whether or not a joint GIS program could benefit the DOD. An information technology implementation model was presented as a framework to implement a joint GIS program. It was found that all four armed services use GIS for forward deployments. The Army has its Combat Terrain Information System (CTIS). The Navy's digital nautical charts are a GIS. The Marine Corps has created their Geographically Linked Information Display Environment (GLIDE) program, which is similar to a map repository. Finally, the Air Force has its GeoBase program for …


Making The Business Case For Sustainable Design In The Department Of Defense, David M. Warnke Mar 2004

Making The Business Case For Sustainable Design In The Department Of Defense, David M. Warnke

Theses and Dissertations

Buildings are one of the largest consumers of natural resources, a major source of ecological pollution, and occasionally toxic to human health. Sustainable design is the common term associated with buildings which, during their construction, use, and eventual disposal, seek to minimize their negative impact on the environment and human health. The U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) rating system helps to assess a building's sustainability level. In the Federal Government's push to set the example for the rest of the nation, nearly every Federal Agency has chosen to adopt the LEED assessment tool. Each …


Male Breast Cancer During Finasteride Therapy [4], Shen C. Lee, Robert J. Ellis Feb 2004

Male Breast Cancer During Finasteride Therapy [4], Shen C. Lee, Robert J. Ellis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.


Changes In Pulmonary Arterial Wall Mechanical Properties And Lumenal Architecture With Induced Vascular Remodeling, Robert C. Molthen, Amy Heinrich, Steven Thomas Haworth, Christopher A. Dawson Feb 2004

Changes In Pulmonary Arterial Wall Mechanical Properties And Lumenal Architecture With Induced Vascular Remodeling, Robert C. Molthen, Amy Heinrich, Steven Thomas Haworth, Christopher A. Dawson

Biomedical Engineering Faculty Research and Publications

To explore and quantify pulmonary arterial remodeling we used various methods including micro-CT, high-resolution 3-dimensional x-ray imaging, to examine the structure and function of intact pulmonary vessels in isolated rat lungs. The rat is commonly used as an animal model for studies of pulmonary hypertension (PH) and the accompanying vascular remodeling, where vascular remodeling has been defined primarily by changes in the vessel wall composition in response to hypertension inducing stimuli such as chronic hypoxic exposure (CHE) or monocrotaline (MCT) injection. Little information has been provided as to how such changes affect the vessel wall mechanical properties or the lumenal …


Effects Of Friction Stir Welding On Polymer Microstructure, Seth R. Strand Feb 2004

Effects Of Friction Stir Welding On Polymer Microstructure, Seth R. Strand

Theses and Dissertations

This work establishes the relationships between several key Friction Stir Welding process parameters and the resulting microstructural and flexural properties of the welded joint. A series of four single parameter experiments were run. The parameters investigated were pin diameter, feedrate, shoe temperature, and pressure time. Butt welds were made in 6 mm thick stress-relieved extruded polypropylene sheet. Three-point bend tests were used to determine the ultimate flexural strength and coincident strain. The maximum bend angle before failure was used to label the welds as "good or bad." An optical microscope capable of cross polarization was used to examine and photograph …


Proposal For No-Cost Extension And Re-Scope For Unlv Trp Project: Neutron Multiplicity Measurements For The Afci Program (Advanced Fuel Cycle Initiative), Denis Beller Feb 2004

Proposal For No-Cost Extension And Re-Scope For Unlv Trp Project: Neutron Multiplicity Measurements For The Afci Program (Advanced Fuel Cycle Initiative), Denis Beller

Transmutation Sciences Physics (TRP)

The U.S. Advanced Fuel Cycle Initiative (AFCI) is a program to develop economic and environmental methods to reduce the impact of waste from commercial nuclear fuel cycles. One concept for near-complete destruction of waste isotopes from used nuclear fuel is accelerator-driven transmutation. High-power accelerators would be used to produce high-energy charged particles, which then collide with heavy metal targets to create a cascade of neutrons. These neutrons then cause a nuclear chain reaction in subcritical systems. Fission neutrons then transmute fissile waste isotopes as well as other problematic isotopes such as technetium-99 and iodine-129. To design these systems, complex reactor …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 4, February 2004, College Of Engineering And Computer Science, Wright State University Feb 2004

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 4, February 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Acuta Enews February 2004, Vol. 33, No. 2 Feb 2004

Acuta Enews February 2004, Vol. 33, No. 2

ACUTA Newsletters

ln This lssue

Nominate Now for 2004-05 Board of Directors

From the President................................... Walter L' Czerniak

Coverage for Wireless Phone Services ............................. Howie Frisch, UT Starcom

Semer Recertifies as CAE

Tech Talk....................... Kevin Tanzillo, Dux Public Relations

DC Update............................ Whitney Johnson, Retired, Northern Michigan Univ.

Be a Panelist at a Regional Workshop

WLNP Part 2................................. Ed Quinn, The Ohio State University

Upload Documents to ACUTA Resource Library

New Safeguards Against lD Theft

lnstitutional Excellence Award Deadline ls February 6

Post Jobs Online

Welcome New Members


Geometric Approach To Detecting And Locating Cracks In Thin Plates By Lamb Wave Reflection: Case Of Moving Transducer, Jose R. Mares, Roberto A. Osegueda, Nagaswaroopa Kaukuri, Vladik Kreinovich Feb 2004

Geometric Approach To Detecting And Locating Cracks In Thin Plates By Lamb Wave Reflection: Case Of Moving Transducer, Jose R. Mares, Roberto A. Osegueda, Nagaswaroopa Kaukuri, Vladik Kreinovich

Departmental Technical Reports (CS)

This paper portrays work for the development of a Lamb wave scanning method for the detection of defects in thin plates. The approach requires the generation of an ultrasonic A0 and S0-mode Lamb wave using an incident transmitter excited with a tone burst centered at a near non-dispersive frequency. With a fixed relative separation both transmitter and receiving transducer remotely scan a specific line section of the plate. The arrival time information coming from incident and reflected waves contain information associated with the location of reflection surfaces or potential flaws. The Hilbert-Huang transform is applied to the intrinsic mode functions …


Using Covers To Minimize Odor And Gas Emissions From Manure Storages, José R. Bicudo, David R. Schmidt, Larry D. Jacobson Feb 2004

Using Covers To Minimize Odor And Gas Emissions From Manure Storages, José R. Bicudo, David R. Schmidt, Larry D. Jacobson

Agricultural Engineering Extension Publications

Odor emissions from animal production sites are typically the leading cause of nuisance complaints. Locating facilities far from neighbors is often a solution to the odor problem, but this is not always an option for producers. Most often, reducing odor emissions from the farm is the only option available.


Fatty Acid Composition And Oxidation Of Lipids In Korean Catfish, K. T. Hwang, J. E. Kim, S. G. Kang, S. T. Jung, H. J. Park, Curtis L. Weller Feb 2004

Fatty Acid Composition And Oxidation Of Lipids In Korean Catfish, K. T. Hwang, J. E. Kim, S. G. Kang, S. T. Jung, H. J. Park, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study determined the lipid content and FA composition of muscle and a mixture of muscle and viscera from Korean catfish as well as lipid oxidation and hydrolysis. Lipid content and FA compositions in Korean catfish, which were purchased every month or two during September 1999–July 2000, were analyzed. Lipid oxidation and hydrolysis were determined as PV, thiobarbituric acid value, and FFA in the muscle and the mixture during storage at 2°C for 12 d and –14°C for 9 wk. Lipid contents of the muscle and the mixture were 3.2 (w/w) and 5.4%, respectively. Oleic acid was the most abundant …


Optical Characterization Of Ceramic Thin Films: Applications In Low-Temperature Solid Oxide Fuel-Cell Materials Research, Vladimir Petrovsky, Tatiana Petrovsky, Harlan U. Anderson, Brian P. Gorman Feb 2004

Optical Characterization Of Ceramic Thin Films: Applications In Low-Temperature Solid Oxide Fuel-Cell Materials Research, Vladimir Petrovsky, Tatiana Petrovsky, Harlan U. Anderson, Brian P. Gorman

Materials Science and Engineering Faculty Research & Creative Works

Characterization of thin film solid oxide fuel-cell materials can be difficult due to the range of porosities in electrodes and electrolytes as well as the nano-sized pores and particles. In this study, optical characterization techniques such as ultraviolet-visible transmission and reflection spectrophotometry are illustrated as methods for achieving information about the film density from the film refractive index as well as the film thickness. These techniques were used to investigate the sintering process of colloidal CeO2 on sapphire substrates and polymeric precursor-derived ZrO2:16%Y (YSZ) thin films on silicon over the temperature range 400-1000 °C, and the results were compared with …


Bs News Feb 2004

Bs News

Building Services Engineering

No abstract provided.