Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Mountain biking (2)
- Scheduling (2)
- Signal-to-noise ratio (SNR) (1)
- A. Structural materials (1)
- AFM (1)
-
- Accidents (1)
- Aeroelastic flutter (1)
- Aeroelastic tailoring (1)
- Aeroelasticity (1)
- Airlift (1)
- Artificial neural network (1)
- Aspect ratio effects (1)
- Atomic force microscopy (1)
- Attractants (1)
- Aurora (1)
- Autoignition; Rapid compression machine; Shock tube; JP-8; JP-5 (1)
- B. Mechanical properties (1)
- B. Strength (1)
- B. anthracis (1)
- Bacillus (1)
- Back propagation (1)
- Battered-child syndrome (1)
- Biogeochemical reductive dechlorination (1)
- Biomimetic (1)
- Body composition (1)
- Braking (1)
- C. Sandwich (1)
- Cavity ignition (1)
- Cellular structure (1)
- Ceramics (1)
Articles 31 - 51 of 51
Full-Text Articles in Engineering
Atomic Force Microscope Tip Spontaneous Retraction From Dielectric Surfaces Under Applied Electrostatic Potential, S. F. Lyuksyutov, P. B. Paramonov, O. V. Mayevska, M. A. Reagan, E. Sancaktar, R. A. Vaia, S. Juhl
Atomic Force Microscope Tip Spontaneous Retraction From Dielectric Surfaces Under Applied Electrostatic Potential, S. F. Lyuksyutov, P. B. Paramonov, O. V. Mayevska, M. A. Reagan, E. Sancaktar, R. A. Vaia, S. Juhl
U.S. Air Force Research
A time-resolved method for tip’ retraction at µs-scale away from dielectric surfaces has been developed. Analysis of the forces in the system comprising AFM tip, water meniscus, and polymer film suggests that an electrostatic repulsion of the tip from the surface in the double-layered (water and polymer) system, and water condensation in the tip–surface junction are the dominant factors enabling the mechanical work for tip retraction. Nanostructures of 5–80nm height are formed in polymeric surfaces as a result. This interesting physical phenomenon could be used for nanostructures patterning in polymeric materials at enhanced aspect ratio.
Force Protection Using Composite Sandwich Structures, R. L. Sierakowski, M. L. Hughes
Force Protection Using Composite Sandwich Structures, R. L. Sierakowski, M. L. Hughes
U.S. Air Force Research
In the recent past, advances have been made in the attempt to utilize composite materials as components in protective structures such as those employed by the Air Force to secure critical military assets. In such applications, where lightweight materials that exhibit large levels of energy absorption and high strength/stiffness characteristics are desirable, composite sandwich constructions offer an attractive solution.
In an attempt to evaluate the suitability of certain sandwich structures for use in force protection applications, several sandwich constructions with somewhat novel core materials were identified. A group of thermoplastic core materials have been developed that possess features of both …
Atomic Force Microscopy Of Bacillus Spore Surface Morphology, Ruth A. Zolock, Guangming Li, Charles Bleckmann, Larry Burggraf, Douglas C. Fuller
Atomic Force Microscopy Of Bacillus Spore Surface Morphology, Ruth A. Zolock, Guangming Li, Charles Bleckmann, Larry Burggraf, Douglas C. Fuller
U.S. Air Force Research
Bacillus spore surface morphology was imaged with atomic force microscopy (AFM) to determine if characteristic surface features could be used to distinguish between four closely related species; Bacillus anthracis Sterne strain, Bacillus thuringiensis var. kurstaki, Bacillus cereus strain 569, and Bacillus globigii var. niger. AFM surface height images showed an irregular topography across the curved upper surface of the spores. Phase images showed a superficial grain structure with different levels of phase contrast and significant differences in average surface morphologies among the four species. Although spores of the same species showed similarities, there was significant variability within each …
United States Air Force Posture Statement 2005, U.S. Air Force
United States Air Force Posture Statement 2005, U.S. Air Force
U.S. Air Force Research
Today's security environment is characterized by change and ambiguity. The future will include a variety of challenges, including the risk of catastrophic attacks on the homeland and possibly of disruptive technological breakthroughs by our adversaries.
Decision Support For The Career Field Selection Process At The Us Air Force Academy, Andrew P. Armacost, James K. Lowe
Decision Support For The Career Field Selection Process At The Us Air Force Academy, Andrew P. Armacost, James K. Lowe
U.S. Air Force Research
Each year, the US Air Force Academy graduates nearly 1000 young men and women. To support the decision of which cadets will be classified into which career fields, we describe a linear programming formulation with appealing computational properties that enable it as the core of a decision support tool. We explore methods for measuring and balancing cadets' class standing, Air Force career field requirements, and cadets' career field preferences in the context of this model. Our computational experiments demonstrate the improvement of this method over previous classification approaches, yielding more than 10% increase in the number of cadets assigned to …
Laboratory Evaluation Of Colored Light As An Attractant For Female Aedes Aegypti, Aedes Albopictus, Anopheles Quadrimaculatus, And Culex Nigripalpus, Douglas A. Burkett, Jerry F. Butler
Laboratory Evaluation Of Colored Light As An Attractant For Female Aedes Aegypti, Aedes Albopictus, Anopheles Quadrimaculatus, And Culex Nigripalpus, Douglas A. Burkett, Jerry F. Butler
U.S. Air Force Research
Mosquito feeding activity was monitored in an electronic apparatus (visualometer), having ten ports, illuminated from below with narrow bandwidths of light (700, 650, 600, 550, 500, 450, 400, or 350 nm). Responses of adult female Aedes albopictus Skuse, Ae. aegypti (L.), Anopheles quadrimaculatus, Say and Culex nigripalpus Theobald to feeding stations (blood containers) over each light port. No-light and broad spectrum white light were used as controls. Color preferences were based on electronic detection of feeding times. Aedes aegypti showed no significant feeding preferences over any of the colors. Conversely, Ae. albopictus, An. quadrimaculatus, and Cx. nigripalpus showed …
The U.S. Air Force Remotely Piloted Aircraft And Unmanned Aerial Vehicle Strategic Vision, U.S. Air Force
The U.S. Air Force Remotely Piloted Aircraft And Unmanned Aerial Vehicle Strategic Vision, U.S. Air Force
U.S. Air Force Research
The U.S. Air Force Remotely Piloted Aircraft and Unmanned Aerial Vehicle Strategic Vision (hereafter referred to as The Strategic Vision) examines the future role of Air Force remotely piloted aircraft (RPAs) and unmanned aerial vehicles (UAVs) and their integration with other Air Force and joint systems. The Strategic Vision is presented in five sections.
Sample Preparation And Characterization Of Artificially Aged Aircraft Coatings For Microstructural Analysis, Lisa M. Farrier, Stephen A. Szaruga
Sample Preparation And Characterization Of Artificially Aged Aircraft Coatings For Microstructural Analysis, Lisa M. Farrier, Stephen A. Szaruga
U.S. Air Force Research
The paper describes a method for metallographic preparation of artificially aged aircraft coatings. In order to better understand the in-service performance and identify degradation mechanisms of an aircraft coating, complete characterization of the microstructure is essential. This paper discusses metallographic sample preparation and subsequent microscopy techniques (light optical microscopy, scanning electron microscopy) for characterization of a standard polyurethane aircraft coating system. The preparation method has proven to produce good, consistent results on a wide range of laboratory-produced simulated environmental exposures.
The military specification coating system under study (MIL-PRF-85285C and MIL-PRF-23377G) degrades severely after accelerated weathering. Typical degradation includes deterioration of …
Improving Pilot Mental Workload Classification Through Feature Exploitation And Combination: A Feasibility Study, Jeremy B. Noel, Kenneth W. Bauer, Jr., Jeffrey W. Lanning
Improving Pilot Mental Workload Classification Through Feature Exploitation And Combination: A Feasibility Study, Jeremy B. Noel, Kenneth W. Bauer, Jr., Jeffrey W. Lanning
U.S. Air Force Research
Predicting high pilot mental workload is important to the United States Air Force because lives and aircraft have been lost due to errors made during periods of flight associated with mental overload and task saturation. Current research efforts use psychophysiological measures such as electroencephalography (EEG), cardiac, ocular, and respiration measures in an attempt to identify and predict mental workload levels. Existing classification methods successfully classify pilot mental workload using flight data for a single pilot on a given day, but are unsuccessful across different pilots and/or days. We demonstrate a small subset of combined and calibrated psychophysiological features collected from …
Biomimetic Model Of Skeletal Muscle Isometric Contraction: I. An Energetic–Viscoelastic Model For The Skeletal Muscle Isometric Force Twitch, C. A. Phillips, D. W. Repperger, A. T. Neidhard-Doll, D. B. Reynolds
Biomimetic Model Of Skeletal Muscle Isometric Contraction: I. An Energetic–Viscoelastic Model For The Skeletal Muscle Isometric Force Twitch, C. A. Phillips, D. W. Repperger, A. T. Neidhard-Doll, D. B. Reynolds
U.S. Air Force Research
This paper describes a revision of the Hill-type muscle model so that it will describe the chemo-mechanical energy conversion process (energetic) and the internal-element sti2ness variation (viscoelastic) during a skeletal muscle isometric force twitch contraction. The derivation of this energetic–viscoelastic model is described by a 3rst-order linear ordinary di2erential equation with constant energetic and viscoelastic coe5cients. The model has been implemented as part of a biomimetic model, which describes the excitation–contraction coupling necessary to drive the energetic–viscoelastic model. Finally, the energetic–viscoelastic model is validated by comparing its isometric force–time pro3le with that of various muscles reported in the literature.
United States Air Force Posture Statement 2004, U.S. Air Force
United States Air Force Posture Statement 2004, U.S. Air Force
U.S. Air Force Research
In 2003, U.S. and coalition military operations produced unprecedented mission successes - across the spectrum of conflict and around the globe. The joint warfighting team demonstated combat capability never previously witnessed in the history of conflict.
The Houston Conference Revisited, Ralph M. Reitan, Jim Hom, Janet Van De Voorde, Daniel E. Stanczak, Deborah Wolfson
The Houston Conference Revisited, Ralph M. Reitan, Jim Hom, Janet Van De Voorde, Daniel E. Stanczak, Deborah Wolfson
U.S. Air Force Research
This paper presents a review and critique of the Houston Conference on Specialty Education and Training in Clinical Neuropsychology, together with an informal summary of opinions of a number of neuropsychologists. Issues regarding the role of the Clinical Neuropsychology Synarchy (CNS) and the applicability of the conference policies are offered. Several deficiencies and limitations of the policy statement are discussed. An informal survey of neuropsychologists interested in the Houston Conference indicates rather different opinions concerning the training and education of neuropsychologists. It is our contention that the results of the Houston Conference can only be considered controversial at best and …
Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D. D. Sentman, E. M. Wescott, R. H. Picard, J. R. Winick, H. C. Stenbaek-Nielsen, E. M. Dewan, D. R. Moudry, F. T. São Sabbas, M. J. Heavner, J. Morrill
Simultaneous Observations Of Mesospheric Gravity Waves And Sprites Generated By A Midwestern Thunderstorm, D. D. Sentman, E. M. Wescott, R. H. Picard, J. R. Winick, H. C. Stenbaek-Nielsen, E. M. Dewan, D. R. Moudry, F. T. São Sabbas, M. J. Heavner, J. Morrill
U.S. Air Force Research
The present report investigates using simultaneous observations of coincident gravity waves and sprites to establish an upper limit on sprite-associated thermal energy deposition in the mesosphere. The University of Alaska operated a variety of optical imagers and photometers at two ground sites in support of the NASA Sprites99 balloon campaign. One site was atop a US Forest Service lookout tower on Bear Mt. in the Black Hills, in western South Dakota. On the night of 18 August 1999 we obtained from this site simultaneous images of sprites and OH airglow modulated by gravity waves emanating from a very active sprite …
Computing Small-Fleet Aircraft Availabilities Including Redundancy And Spares, Jeffery K. Cochran, Theodore P. Lewis
Computing Small-Fleet Aircraft Availabilities Including Redundancy And Spares, Jeffery K. Cochran, Theodore P. Lewis
U.S. Air Force Research
Logistics support is a key element of aircraft transportation systems. This paper is concerned with the impact of aircraft spares provisioning decisions on the availability of aircraft. Spares provisioning in this context is complicated by the fact that spares may be shared across aircraft and that aircraft may have redundant systems. In addition, decisions concerning aircraft spares support require a rapid response for safety reasons. Analytical models have proven to provide a quicker response time than corresponding simulation models. There is an existing analytical model that includes the effect of redundancy and spares, but the underlying assumption is that a …
Victim, Perpetrator, Family, And Incident Characteristics Of Infant And Child Homicide In The United States Air Force, Don R. Lucas, Kelley C. Wezner, Joel S. Milner, Thomas R. Mccanne, I. Nell Harris, Carla Monroe-Posey, John P. Nelson
Victim, Perpetrator, Family, And Incident Characteristics Of Infant And Child Homicide In The United States Air Force, Don R. Lucas, Kelley C. Wezner, Joel S. Milner, Thomas R. Mccanne, I. Nell Harris, Carla Monroe-Posey, John P. Nelson
U.S. Air Force Research
Objective: The present study describes factors related to fatal abuse in three age groups in the United States Air Force (USAF).
Method: Records from 32 substantiated cases of fatal child abuse in the USAF were independently reviewed for 60 predefined factors.
Results: Males were over-represented in young child victims (between 1 year and 4 years of age) and child victims (between 4 years and 15 years of age) but not in infant victims (between 24 hours and 1 year of age). African-American infant victims and perpetrators were over-represented. Younger victims were more likely to have been previously …
Cd-Rom Nutrient Analysis Database Assists Self-Monitering Behavior Of Active Duty Air Force Personnel Receiving Nutrient Counseling For Weight Loss, Jane E. Heetderks-Cox, Betty B. Alford, Carolyn M. Bednar, Cynthia J. Heiss, Lisa A. Tauai, Kimberly K. Edgren
Cd-Rom Nutrient Analysis Database Assists Self-Monitering Behavior Of Active Duty Air Force Personnel Receiving Nutrient Counseling For Weight Loss, Jane E. Heetderks-Cox, Betty B. Alford, Carolyn M. Bednar, Cynthia J. Heiss, Lisa A. Tauai, Kimberly K. Edgren
U.S. Air Force Research
This study observed the effect of using a computerized vs. a manual method of self-monitoring among Air Force personnel receiving nutrition counseling for weight loss.
U.S. Air Force Long-Range Strike Aircraft White Paper, U.S. Air Force
U.S. Air Force Long-Range Strike Aircraft White Paper, U.S. Air Force
U.S. Air Force Research
As a result of DoD transformation plans and recent operational experience (Air War Over Serbia and Operation ENDURING FREEDOM) portions of the 1999 U.S. Air Force White Paper on Long Range Bombers have become outmoded. In October 2001, the Secretary of the Air Force directed an updated Long-Range Strike Aircraft White Paper incorporating our new defense planning guidance. This document provides an update to the 1999 White Paper and reflects current decisions concerning bomber force structure and basing. While modification plans remain largely intact, the focus has been refined to support the Global Strike Task Force concept.
Low-Latitude Auroras: The Magnetic Storm Of 14–15 May 1921, S. M. Silverman, E. W. Cliver
Low-Latitude Auroras: The Magnetic Storm Of 14–15 May 1921, S. M. Silverman, E. W. Cliver
U.S. Air Force Research
We review solar/geophysical data relating to the great magnetic storm of 14–15 May 1921, with emphasis on observations of the low-latitude visual aurora. From the reports we have gathered for this event, the lowest geomagnetic latitude of de6nite overhead aurora (coronal form) was 40° and the lowest geomagnetic latitude from which auroras were observed on the poleward horizon in the northern hemisphere was 30°. For comparison, corresponding overhead/low-latitude values of 48°/32° and 41°/20° were reported for the great auroras on 28–29 August and 1–2 September 1859, respectively. However, for the 1921 event, there is a report of aurora from Apia, …
Lab Fattening And Non-Invasive Estimates Of Body Composition In Deer Mice, Edward T. Unangst, Michael J. Blair, Matthew W. Granger, David W. Hale
Lab Fattening And Non-Invasive Estimates Of Body Composition In Deer Mice, Edward T. Unangst, Michael J. Blair, Matthew W. Granger, David W. Hale
U.S. Air Force Research
Total body electrical conductivity measurements and lipid composition were determined for the deer mouse (Peromyscus maniculatus) to derive species specific calibration equations for use with EM-SCAN estimates of lean and fat tissue. For each individual, total body electrical conductivity was measured by EM-SCAN, and actual lipid content was determined by chemical extraction. Then, using estimated and actual lipid values, separate calibration equations were generated for freshly captured (lean) and laboratory maintained (fat) individuals, and a combined equation was derived for all individuals. These equations were variable in the accuracy of lipid estimates; the lowest relative error estimate (percent …
Control Of The Air: The Enduring Requirement, Richard P. Hallion
Control Of The Air: The Enduring Requirement, Richard P. Hallion
U.S. Air Force Research
Throughout the military history of the twentieth century, the role of aerospace forces has become more predominant. Today, wars typically start, are prosecuted, and reach their decisive culminating point--whether surrender of a foe, agreement to a ceasefire, or the ceasing of combat operations--thanks to air action. Given these circumstances, to lose control of the air is to lose a war, particularly in an era (as we now are in since the end of the Cold War) when deployable overseas forces are small, and, thus, particularly vulnerable to the tremendous leverage an opponent gains by sudden and swift air attack. If …
Npdes Permitting For Storm Water Discharges Associated With Industrial Activity, Paul Makowski, John G. Garland Iii
Npdes Permitting For Storm Water Discharges Associated With Industrial Activity, Paul Makowski, John G. Garland Iii
U.S. Air Force Research
Recent changes to the National Pollutant Discharge Elimination System (NPDES) program require that storm water discharges associated with industrial activity and from municipal separate storm sewer systems serving a population of 100,000 or more be regulated under the NPDES program. These changes greatly expanded the number of industrial facilities subject to the NPDES program. An industrial facility that is subject to the regulation must apply for a storm water permit based on application requirements that were recently established. The NPDES permit application process for storm water discharges associated with industrial activity is discussed.