| Interfacing a Microelectromechanical System (MEMS) Sensor Array for Traumatic Brain Injury Detection with a Microcontroller |
Oct 2012 |
38 pages |
| Authors:
Timothy C Lee; Luke J Currano; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
|
 | Traumatic brain injuries (TBIs) result from exposure to high accelerations and are a serious threat to Soldiers in close contact with improvised explosive devices as well as sports players who are frequently involved in collisions. To improve TBI detection, the U.S. Army Research Laboratory (ARL) has developed a sensor small enough to be mounted in the ear. The sensor consists of an array of 3-axis microelectromechanical system (MEMS) acceleration threshold ... |
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| The Aerodynamics of a Maneuvering UCAV 1303 Aircraft Model and its Control through Leading Edge Curvature Change |
Sep 2012 |
83 pages |
| Authors:
Christopher M Medford; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This study investigates the aerodynamic effects of modifying the leading edge on an unmanned combat air vehicle (UCAV) 1303. Literature suggests that leading edge accelerations are reduced for rounder leading edges and stall characteristics are altered. These phenomena are examined using the previously tested 1/72 scale model with a 47-degree leading edge sweep and a cranked trailing edge delta wing with fuselage. The study consists of both flow visualization and ... |
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| Revealing Companions to Nearby Stars with Astrometric Acceleration |
Jul 2012 |
11 pages |
| Authors:
Andrei Tokovinin; Markus Hartung; Thomas L Hayward; Valeri W Makarov; NAVAL OBSERVATORY WASHINGTON DC
|
| A subset of 51 Hipparcos astrometric binaries among FG dwarfs within 67 pc has been surveyed with the Near-Infrared Coronagraphic Imager adaptive optics system at Gemini-S, directly resolving for the first time 17 subarcsecond companions and 7 wider ones. Using these data together with published speckle interferometry of 57 stars, we compare the statistics of resolved astrometric companions with those of a simulated binary population. The fraction of resolved companions ... |
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| Piezoelectric, Solar and Thermal Energy Harvesting for Hybrid Low-Power Generator Systems With Thin-Film Batteries |
Jan 2012 |
14 pages |
| Authors:
P Gambier; S R Anton; N Kong; A Erturk; D J Inman; LOS ALAMOS NATIONAL LAB NM ENGINEERING INSTITUTE
|
| The harvesting of ambient energy to power small electronic components has received tremendous attention over the last decade. The research goal in this field is to enable self-powered electronic components for use particularly in wireless sensing and measurement applications. Thermal energy due to temperature gradients, solar energy and ambient vibrations constitute some of the major sources of energy that can be harvested. Researchers have presented several papers focusing on each ... |
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| An Experimental Investigation into the Transit Performance of a Titanium-Water Loop Heat Pipe Subjected to a Steady-Periodic Acceleration Field (Postprint) |
Jan 2012 |
40 pages |
| Authors:
James D Scofield; Kirk L Yerkes; David L Courson; Hua Jiang; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| The objective of this research is to experimentally investigate the transient operating characteristics of a titanium-water loop heat pipe subjected to a combined steady-state evaporator input heat rate and a steady-periodic acceleration field. For this experimental investigation, a steady-periodic acceleration field, in the form of a sine wave, was generated using a centrifuge table. Radial acceleration peak-to-peak values and frequency of the sine wave were defined prior to conducting each ... |
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| Optimal Pulse Shapes for SHPB Tests on Soft Materials |
Dec 2011 |
20 pages |
| Authors:
Mike Scheidler; John Fitzpatrick; Reuben Kraft; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| For split Hopkinson pressure bar (SHPB) tests on soft materials, the goals of homogeneous deformation and uniform uniaxial stress in the specimen present experimental challenges, particularly at higher strain rates. It has been known for some time that attainment of these conditions is facilitated by reducing the thickness of the specimen or by appropriately shaping the loading pulse. Typically, both methods must be employed. Pulse shapes are often tailored to ... |
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| How the Degree of Accuracy of an Inertial Measurement Unit (IMU) Influences the Miss Distance of a Gun-Launched Precision Munition |
Sep 2011 |
93 pages |
| Authors:
David W Panhorst; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Precision Munition projectiles guide to an area to hit their target. The projectile must read position in-flight and measure deviations from the intended flight path. This allows the projectile to correct and maintain the intended trajectory. An Inertial Measurement Unit (IMU) device measures the relative movement of a projectile throughout flight and measures the deviation from the intended path, enabling the projectile to course correct. The purpose of this thesis ... |
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| Integration of Control Algorithms for Quadrotor UAV's Using an Indoor Sensor Environment |
Sep 2011 |
65 pages |
| Authors:
Bryan D Watts; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This thesis develops an architecture that facilitates the design and indoor testing of control algorithms implemented onboard quadrotor UAV's using an ultra-wideband (UWB) indoor positioning solution from Ubisense. Initially, details are provided on basic quadrotor dynamics, the setup of the indoor sensor environment, and the communication scheme. A thorough analysis is conducted on the accuracy and estimation lag of Ubisense UWB sensors for providing indoor position information to the quadrotor. ... |
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| Limited Evaluation of AIM-9 Control Surface Effects on F-16 LCO Characteristics |
AUG 2011 |
13 pages |
| Authors:
Anthony P. Massett; Reinald G. Groult; Robert T. Ungerman; Jason B. Honabarger; Jared E. Salk; Pierluigi De Paolis; Timothy R. Jorris; AIR FORCE FLIGHT TEST CENTER EDWARDS AFB CA
|
| Limit Cycle Oscillation (LCO) is a self-sustained airframe structural response due to interaction between airframe aeroelastic properties and flight condition aerodynamic effects. F-16 LCO has typically resulted in lateral motions of the fuselage and crew that could have operational impacts on such things as pilot fatigue, weapons tracking or structural integrity. Historic flight test data could not isolate the effect that aerodynamic differences had on LCO over mass and inertia ... |
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| Drop Calibration of Accelerometers for Shock Measurement |
Aug 2011 |
49 pages |
| Authors:
Andrew Krelle; DEFENSE SCIENCE AND TECHNOLOGY ORGANIZATION VICTORIA (AUSTRALIA) MARITIME PLATFORMS DIV
|
| This report details the Drop Calibration Method for determining the sensitivity of shock accelerometers. The Drop Calibration Method requires the accelerometer under calibration and either a traceable acceleration standard or a traceable force transducer standard to undergo a series of drop impacts. The sensitivity of the accelerometer is determined by comparing the outputs of the accelerometer and the standard. By appropriate characterisation of both the accelerometer's and the standard's data ... |
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| Ground and Flight Testing of Non-Chrome Paint Systems. Part 1. Acceleration Factors |
Aug 2011 |
17 pages |
| Authors:
W H Abbott; BATTELLE COLUMBUS OH
|
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| Analysis of Track Fusion Using the Reduced State Estimator |
Jul 2011 |
8 pages |
| Authors:
George J Foster; NAVAL SURFACE WARFARE CENTER DAHLGREN DIV VA
|
| We evaluate the performance of track fusion of two-state tracks based on individual track estimates. The individual track estimates are evaluated using a Reduced State Estimator that provides a separate estimate of the filtered random error and the bias resulting from target acceleration. By separating the bias and random portions of the errors, the filters and fusion process can be optimized to minimize cost functions specific to each application. |
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| Granular Material Response to Dynamic Shock Compression: A Study of SiO2 in the Form of Sand and Soda Lime Glass Beads |
JUN 2011 |
105 pages |
| Authors:
James R. Santymire; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| There has been increased interest in the dynamic behavior of sand throughout scientific and engineering communities due, mainly, to its damaging mechanisms against armored military vehicles upon sudden acceleration from buried improvised explosive devices. NASA is also interested in the properties of sand as a stimulant for powdered planetary materials. This thesis focused on developing the experimental techniques to successfully measure its dynamic response to shock impacts. However, sand has ... |
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| Maintainability Data Decision Methodology (MDDM) |
Jun 2011 |
23 pages |
| Authors:
Jr Nierwinski John; ARMY MATERIEL SYSTEMS ANALYSIS ACTIVITY ABERDEEN PROVING GROUND MD
|
| Organizations within the U.S. Army [i.e. Communications-Electronics Command (CECOM)] and other government organizations have the need to evaluate Maintenance Manpower requirements for systems (i.e. Power Generators, etc.) where fully developed maintenance data is NOT available. Maintenance Manpower requirements are computed by multiplying an estimated maintenance ratio (man-hours per usage) by a one year wartime usage, which results in a total number of recommended maintenance man-hours. Army organizations need to know ... |
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| Ride Quality Index - A New Approach to Quantifying the Comparison of Acceleration Responses of High Speed Craft |
Jun 2011 |
23 pages |
| Authors:
Michael Riley; Tim Coats; Kelly Haupt; Don Jacobson; NAVAL SEA SYSTEMS COMMAND WASHINGTON DC
|
| The objective of these briefing charts was to present a simplified approach to quantifying ride quality when comparing wave impacts for different craft, different sea states, different speeds or different gage locations. |
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| Ion Velocity and Plasma Potential Measurements of a Cylindrical Cusped Field Thruster |
19 May 2011 |
13 pages |
| Authors:
N A MacDonald; C V Young; M A Cappelli; Jr Hargus W A; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIR/SPACE AND MISSILE PROPULSION DIV
|
| Measurements of the most probable time-averaged axial ion velocities and plasma potential within the acceleration channel and in the plume of a straight channeled cylindrical cusped field thruster operating on xenon are presented. Ion velocities for the thruster are derived from laser-induced fluorescence measurements of the 5d[4](7/2)-6p[3](5/2) xenon ion excited state transition centered at _ = 834.72 nm. Plasma potential measurements are made using a floating emissive probe with a ... |
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| Role of Nonreceptor Protein Kinase Ack 1 in Prostate Cancer |
MAY 2011 |
40 pages |
| Authors:
Charlene Rivera; NORTH CAROLINA UNIV AT CHAPEL HILL
|
| Previously, we have shown that constitutively active Ack1 (caAck1) directly binds and tyrosine phosphorylates the androgen receptor (AR), resulting in ligand-independent AR activity. Moreover, caAck1 transforms LNCaP cells into androgen independent and highly invasive tumors in nude mice. However, the role of Ack1 in prostate cancer initiation and progression within the context of a complex organ remains poorly understood. To address this question, we generated transgenic mice expressing the caAck1 ... |
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| Optimization of One-Dimensional Aluminum Foam Armor Model for Pressure Loading (Briefing charts) |
12 APR 2011 |
17 pages |
| Authors:
John C. Goetz; Andres Tovar; John Renaud; NOTRE DAME UNIV IN
|
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| Urban Turbulence and Wind Gusts for Micro Air Vehicle Bio-inspired Designs |
Mar 2011 |
28 pages |
| Authors:
Cheryl L Klipp; Edward Measure; ARMY RESEARCH LAB ADELPHI MD COMPUTATIONAL AND INFORMATION SCIENCES DIRECTORATE
|
| We discuss the effects of wind turbulence encountered in an urban street canyon on very small unmanned aerial vehicles (UAVs) in the context of field data from the Joint Urban 2003 Experiment in Oklahoma City, OK. We present equations for the aerodynamics of such a UAV and derive equations to estimate the torque and forces encountered as a function of turbulent changes in wind velocity. We use sonic anemometer data ... |
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| Scalable Learning for Geostatistics and Speaker Recognition |
Jan 2011 |
197 pages |
| Authors:
Balaji V Srinivasan; MARYLAND UNIV COLLEGE PARK DEPT OF COMPUTER SCIENCE
|
| With improved data acquisition methods, the amount of data that is being collected has increased several fold. One of the objectives in data collection is to learn useful underlying patterns. In order to work with data at this scale, the methods not only need to be effective with the underlying data, but also have to be scalable to handle larger data collections. This thesis focuses on developing scalable and effective ... |
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| The Role of Lower Extremity Joint Powers in Successful Stair Ambulation |
2011 |
4 pages |
| Authors:
Jason M. Wilken; Emily H. Sinitski; Elizabeth A. Bagg; BROOKE ARMY MEDICAL CENTER FORT SAM HOUSTON TX
|
| Ascending stairs is an important functional activity that is affected by lower extremity pathology including amputation. Although several studies have demonstrated stair ascent is more challenging than level ground walking, our understanding of the mechanics remains limited. The purpose of this study was to determine the association between lower extremity joint power generation and vertical COM acceleration (COMA) during stair ascent. Twenty-two healthy individuals underwent a biomechanical gait assessment while ... |
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| Induction and Acceleration of Mammary Tumors by Activated P13 Kinase |
JUL 2010 |
4 pages |
| Authors:
Erica Nolte; Steven Anderson; COLORADO UNIV HEALTH SCIENCES CENTER AURORA CO
|
| During this time period the necessary retroviral vectors were developed, used to transduce mammary epithelial cells, and these transduced cells were transferred into the cleared fat pad of recipient mice. Although ductal outgrowth occurred in the cleared fat pads indicating that the transplant was successful, the number of GFP positive ducts that grew out was very low. This was surprising given that a high proportion (greater than 80%) of the ... |
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| Measurement of Exercise Intensity with a Tri-Axial Accelerometer during Military Training |
Oct 2009 |
8 pages |
| Authors:
Klaas R Westerterp; Gerard J Rietjens; Loek Wouters; MAASTRICHT UNIV (NETHERLANDS)
|
| Exercise load and intensity, as reflected in energy expenditure, are determinants of performance. Here, we evaluated a newly developed tri-axial accelerometer for movement registration (Directlife, Philips Research, Eindhoven, The Netherlands) for the assessment of exercise intensity and exercise load at high-intensity field training. Subjects were 16 well-trained men with a mean ( SD) age of 24 3 y and body fat of 15.8 2.1 %. Physical activity was monitored continuously ... |
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| Effect of Wall Sheaths on Ion Trajectories in a Hall Thruster Numerical Model |
Sep-2009 |
12 pages |
| Authors:
Regina M Sullivan; Joseph E Shepherd; Michelle K Scarfe; Ioannis G Mikellides; Lee K Johnson; CALIFORNIA INST OF TECH PASADENA
|
| A 2D framework for solving the sheath equations near a dielectric corner has been developed and applied in a quasi 2D fashion to solve for sheath thickness and potential profile. When appropriate, boundary conditions were taken from an HPHall model of an SPT-70 Hall thruster. Ion paths within the sheath were also calculated. Results suggest that the radial acceleration provided by the sheath has the ability to produce significant changes ... |
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| Numerical Optimization of an Annular Field Reserved Configuration Translation Experiment |
14-Aug-2009 |
16 pages |
| Authors:
Lyon B King; Carrie S Niemela; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Annular field reversed configuration (AFRC) devices form annular plasma toroids between a pair of concentric cylindrical coils. This plasmoid remains detached from the external magnetic _field so that it can be ejected from the coils, making AFRCs viable pulsed inductive plasma accelerators. Though numerous formation studies on AFRCs are available, no successful translation studies have been published. Michigan Technological University, in conjunction with the Air Force Research Laboratory, is investigating ... |
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| Altitude Control of a Single Degree of Freedom Flapping Wing Micro Air Vehicle (Postprint) |
Aug 2009 |
21 pages |
| Authors:
David B Doman; Michael W Oppenheimer; Michael A Bolender; David O Sigthorsson; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE
|
| A control strategy is proposed for a minimally actuated flapping wing micro air vehicle. The Harvard RoboFly vehicle accomplished the first takeoff of an insect scale flapping wing aircraft. This flight demonstrated the capability of the aircraft to accelerate vertically while being constrained by guide-wires to avoid translation and rotation in the other five degrees of freedom. The present work proposes an altitude control scheme that would enable a similar ... |
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| Acceleration of an Initially Moving Projectile: Velocity-Injected Railguns and Their Effect on Pulsed Power |
Jul-2009 |
30 pages |
| Authors:
Del; Miguel Guercio; Alexander Zielinski; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| Calculations are performed for an initially moving projectile and a railgun. The initial velocity is provided by a 26-mm-diameter conventional propellant gun. A plasma armature is assumed for the railgun. The capacitor-based, pulsed power supply (PPS), located at barricade C, Aberdeen Proving Ground, MD, is assumed to provide the electrical energy for boosting the velocity to 2.5 km/s. Various scenarios are examined with respect to electrical pulse shape, the effect ... |
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| The Effect of Variable Gravity on the Cooling Performance of a Partially-Confined FC-72 Spray |
Jul-2009 |
214 pages |
| Authors:
John McQuillen; Travis E Michalak; Kirk L Yerkes; Scott K Thomas; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH PROPULSION DIRECTORATE
|
| This thesis discusses the effects of a variable-gravity environment on the performance of a subcooled partially-confined spray. An experiment, consisting of a test chamber, the associated flow loops, and instrumentation, was fabricated and flown on the NASA Reduced-Gravity Testing Platform. This modified KC-135 aircraft followed a parabolic flight path to provide various acceleration levels. The spray chamber contained two opposing nozzles spraying onto Thick Film Resistor (TFR) heaters, which were ... |
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| Influence of Structural Flexibility on Flapping Wing Propulsion |
Jun-2009 |
180 pages |
| Authors:
Aaron M McClung; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
|
| The influence of structural deformations on the aerodynamic response of a flapping wing configuration was examined using Navier-Stokes based simulation. Two deformation modes, torsion and bending, were considered for an elastic axis along the leading edge of the wing. Both deformation modes influence the velocity and acceleration profile of the wing surface, altering the unsteady aerodynamic phenomena produced by the dynamic wing motion. The spanwise feathering rotation, or torsional response, ... |
|
| Knowledge Management: An Effort to Keep Pace with Information |
04-May-2009 |
31 pages |
| Authors:
Darryl B Martin; NAVAL WAR COLL NEWPORT RI JOINT MILITARY OPERATIONS DEPT
|
| In a network centric environment, a multitude of platforms and communication systems will be linked to provide all levels of command with near real-time data to feed their decision-making cycles. The ability to cope with this abundance of information will depend on the organization's ability to adapt and learn faster than the enemy. To aid this accelerated learning process, knowledge management (KM) allows for the capture and exchange of experiences ... |
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| The Doctrinal Inflexibility Afforded a Branch: How to Break the Paradigm from Risk Avoidance to Opportunity Exploitation |
04-May-2009 |
33 pages |
| Authors:
Steve Pritchard; NAVAL WAR COLL NEWPORT RI JOINT MILITARY OPERATIONS DEPT
|
| Branches and sequels, as defined in U.S. joint doctrine, are designed to allow the commander to plan adequately for the what if and what's next respectively. These doctrinal terms have specific, distinct meaning in application within the operational idea and design process. However, as the dynamic nature of warfare continues to evolve in a subsequently asymmetrical manner, our enemies continue to challenge our doctrinal approaches toward war fighting. The Joint ... |
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| Crystallization Augmentation of Engineering Thermoplastics through Dispersion of Silicon-Containing Nanoparticles |
26-Apr-2009 |
3 pages |
| Authors:
Joseph M Mabry; Gregory R Yandek; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| The mechanical properties and environmental durability of engineering thermoplastics are generally dependent on their degree of molecular ordering. Processing conditions affect observed microstructures in this class of materials and costly annealing procedures can be required to generate adequate levels of crystallinity. It is therefore beneficial to not only develop an understanding of the fundamental physics governing ordering transitions, but to be able to use such knowledge to assert control over ... |
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| Synthesized Synchronous Sampling Technique for Bearing Damage Detection Preprint |
Mar-2009 |
18 pages |
| Authors:
Hai Qiu; Huageng Luo; George Ghanime; Melinda Van Der Hirz; Geo Merwe; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| Differential bearing between the low-pressure turbine (LPT) shaft and high-pressure turbine (HPT) shaft is one of the most vulnerable parts in a turbo machinery engine. Yet, it is one of the most difficult parts to detect the damage signatures, because the signal to noise ratio at the regular sensor locations is usually low. In addition, the speed variations in both the LPT and the HPT can further deteriorate the damage ... |
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| Evolution and Energization of Energetic Electrons in the Inner Magnetosphere |
15-Jan-2009 |
33 pages |
| Authors:
Joseph F Fennell; James L Roeder; AEROSPACE CORP EL SEGUNDO CA
|
| A review is presented of what we know about the evolution and energization of energetic electrons in the inner magneto- sphere. We emphasize what we have learned since the review by Friedel et al. (2002) with the primary result being a greater focus on local acceleration processes and significant new evidence that points to processes that are acting in the region between GPS and geosynchronous altitudes. We use as an ... |
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| Fuel Economy and Mobility of Multi-Wheel Drive Vehicles: Modeling and Optimization Technology |
Jan-2009 |
9 pages |
| Authors:
Vladimir V Vantsevich; Jeremy P Gray; LAWRENCE TECHNOLOGICAL UNIV SOUTHFIELD MI
|
| A distinctive feature of unmanned and conventional terrain vehicles with four or more driving wheels consists of the fact that energy/fuel efficiency and mobility depend markedly not only on the total power applied to all the driving wheels, but also on the distribution of the total power among the wheels. As shown, under given terrain conditions, the same vehicle with a constant total power at all the driving wheels, but ... |
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| Three-Dimensional Diffusion Simulation of Outer Radiation Belt Electrons During the 9 October 1990 Magnetic Storm |
Jan-2009 |
22 pages |
| Authors:
J M Albert; Nigel P Meredith; Richard B Horne; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
|
| Relativistic (l MeV) electron flux increases in the Earth's radiation belts are significantly underestimated by models that only include transport and loss processes, suggesting that some additional acceleration process is required. Here we use a new, threedimensional code that includes radial diffusion and quasi-linear pitch angle and energy diffusion due to chorus waves, including cross terms, to simulate the 9 October 1990 magnetic storm. The diffusion coefficients are activity dependent, ... |
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| Fourier Based Fast Multipole Method for the Helmholtz Equation |
Dec-2008 |
9 pages |
| Authors:
C Cecka; E Darve; STANFORD UNIV CA
|
| The multilevel fast multipole method (MLFMM) is an algorithm that has had great success in reducing the computational time required to find the solution to the Galerkin boundary integral form of the Helmholtz equation. We present a new formulation of the MLFMM using Fourier basis functions rather than spherical harmonics in order to accelerate and simplify the time-critical stages of the algorithm. With modifications to the transfer function in the ... |
|
| Faraday Accelerator With Radio-Frequency Assisted Discharge (FARAD): A New Electrodeless Concept for Plasma Propulsion |
Oct-2008 |
67 pages |
| Authors:
Edgar Choueiri; Kurt Pozin; Ashley Hallock; PRINCETON UNIV NJ ELECTRIC PROPULSION LAB
|
| A new electrodeless accelerator concept that relies on an RF-assisted discharge, an applied magnetic field, and electromagnetic acceleration using an inductive coil is presented. The primary advantage of this concept is that a preionized plasma is employed to lower the initial voltage threshold which applies to the formation of an inductive current sheet in other pulsed inductive accelerator concepts. |
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| Computer Simulation of a 155-mm Projectile in a Scat Gun Assembly |
01-Sep-2008 |
34 pages |
| Authors:
Kenneth P Walsh; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER PICATINNY ARSENAL NJ
|
| This report presents the results of a computer simulation of a 45.36 kg 155-mm projectile as it moves through a scat gun assembly using a FORTRAN program. The experimental data was taken from a test performed by the Analysis Engineering and Technical Division at the U.S. Army Armament Research, Development and Engineering Center, Picatinny Arsenal, New Jersey on 7 April 2007 (test CBR5). The data was filtered using an Abaqus ... |
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| Development of a 3-D Pen Input Device |
01-Sep-2008 |
53 pages |
| Authors:
Deven A Rhett; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The principal objective of this research is to demonstrate the capability of obtaining the acceleration in the navigation frame of a unistroke which can be written on any surface or in the air while correcting integration errors from the measurements of the IMU (Inertial Measurement Unit) of the pen-type input devices. With the core topic of obtaining the acceleration while correcting integration errors, there are four subsidiary research questions relating ... |
|
| Avian Influenza/Pandemic Influenza Program. Addendum |
Aug-2008 |
7 pages |
| Authors:
Ralph W Hapner; JACKSON (HENRY M) FOUNDATION FOR THE ADVANCEMENT OF MILITARY MEDICINE ROCKVILLE MD
|
| The U.S. Army Medical Research Acquisition Activity (USAMRAA) entered into a cooperative agreement between the Department of Defense Global Emerging Infections Surveillance and Response System (DoD-GEIS) central hub and the Henry M. Jackson Foundation for the Advancement of Military Medicine (HJF). DoD GEIS will initiate a plan to provide funding, personnel resources, the centralized management for coordination and reporting related to the DoD efforts for improving global surveillance and efforts ... |
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| Background Pressure Effects on Internal and Near-field Ion Velocity Distribution of the BHT-600 Hall Thruster (Preprint) |
24-Jun-2008 |
10 pages |
| Authors:
Michael R Nakles; Hargus; William A Jr; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Presented is a study of the effects of chamber background pressure on the ion axial velocity distribution within the discharge chamber and in the near-field of the Busek BHT-HD-600 xenon Hall effect thruster. Ion velocity distributions were measured along the acceleration channel centerline using laser-induced fluorescence of the 5d[4](sub 7/2)-6p[3](sub 5/2) xenon ion excited state transition. Measurements were taken at the lowest possible chamber background pressure and a pressure that ... |
|
| Effect of Anode Current Fluctuations on Ion Energy Distributions within a 600 W Hall Effect Thruster (Preprint) |
23-Jun-2008 |
11 pages |
| Authors:
Hargus; William A Jr; Michael R Nakles; Rachel Tedrake; Bruce Pote; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| This work presents axial ion energy distribution measurements within the acceleration channel of the 600 W Busek Co. Inc. BHT-HD-600 laboratory Hall thruster derived from laser-induced fluorescence measurements of the 5d[4](sub 7/2) - 6p[3](sub 5/2) xenon ion excited state transition. Acceleration channel centerline ion energy distributions are measured for three closely related operating conditions which only differ in the magnitude of the radial magnetic field strength. These three operating conditions ... |
|
| Terminal Control of a Variable-Stability Slender Reentry Vehicle |
02 JUN 2008 |
137 pages |
| Authors:
Matthew T. Karmondy; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Various terminal control schemes are applied to a proposed slender reentry vehicle, controlled by two separately-articulating flaps. The flap deflections are summarized as symmetric and asymmetric flap deflections; the former manipulates the drag, lift-curve slope, and static margin; the latter controls the vehicle trim characteristics. The control problem is interesting because the static margin can be actively controlled from statically stable in pitch to statically unstable in pitch. Deflection limits ... |
|
| Near Plume Laser Induced Fluorescence Velocity Measurements of a 600 W Hall Thruster (Preprint) |
02-Jun-2008 |
11 pages |
| Authors:
William A Hargus; Christopher S Charles; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| This work presents the near exit plane velocity field of the Busek Company BHT-600-Circular 600 W Hall thruster at a single operating condition with a 300 V anode potential. The xenon ion propellant velocities were measured using laser induced fluorescence of the 5d[4]7/2 - 6p[3] 5/2 excited state xenon ionic transition at 834.72 nm. Ion velocities were interrogated from the acceleration channel exit plane to a distance 100 mm from ... |
|
| Acceleration Effects on Fluid-Sediment Interaction |
JUN 2008 |
9 pages |
| Authors:
Ole S. Madsen; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CIVIL ENGINEERING
|
| The long-term goals of this research are: (i) to identify all relevant physical processes that participate in and contribute significantly to sediment transport in near-shore coastal waters; (ii) to investigate each of the identified processes in order to understand the underlying physics in a quantitative manner; (iii) to develop simple predictive models for each process; and (iv) to incorporate the simple predictive process-models in a predictive model for beach profile ... |
|
| Portable Neutron Source |
30 MAY 2008 |
50 pages |
| Authors:
J. Davis; G. M. Petrov; NAVAL RESEARCH LAB WASHINGTON DC PLASMA PHYSICS DIV
|
| The angular distribution of neutrons formed in nuclear fusion reactions of a high-energy deuteron beam with a deuterated polyethylene (CD2) was investigated with a Monte Carlo ion beam-target deposition model. The initial conditions were obtained from a two-dimensional particle-in-cell laser-target deposition model. The neutron yield and its angular distribution were studied as a function of peak laser intensity, laser pulse duration and primary target thickness. The proposed scheme for neutron ... |
|
| White Sands Missile Range 2007 Urban Study: Data Processing - Volume DP-3 (Airflow Qualitative Assessment) |
MAY 2008 |
84 pages |
| Authors:
Gail Vaucher; Manuel Bustillos; ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM COMPUTATIONAL AND INFORMATION SCIENCE DIRECTORATE
|
| Urban toxic chemical releases pose a threat to the military and civilians. The White Sands Missile Range (WSMR) Urban Studies address two critical elements in diagnosing airborne hazard releases, namely, airflow (chemical distribution) and stability (chemical concentration). This document provides a qualitative assessment of seven airflow features targeted by the WSMR 2007 Urban Study (W07US). The W07US stability assessment is published separately. The features identified for verification and characterization include ... |
|
| CV-22 Human Vibration Evaluation |
APR 2008 |
70 pages |
| Authors:
Suzanne D. Smith; Jennifer G. Jurcsisn; David R. Bowden; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
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| The purpose of this study was to characterize and assess human vibration exposure onboard the CV-22 Osprey. Triaxial acceleration data were collected at the pilot station and flight engineer station in the cockpit, and at the crew chief station located at the front right side of the cabin. At all three stations, measurements were made at the seat base and at the interfaces between the occupant and seat pan and ... |
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| Parametric Study on the Interior Ballistics of 105 and 155 mm Artillery Guns |
MAR 2008 |
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| Authors:
Vincent Tanguay; DEFENCE RESEARCH AND DEVELOPMENT CANADA VALCARTIER (QUEBEC)
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 | The interior ballistics code IBHVG2 was used to calculate the muzzle velocity and peak acceleration of projectiles ranging in mass from 10 to 50 kg. The simulations were performed with both 105 and 155 mm guns. These were the C3 and LG1 (105 mm and 52-calibre M777 were also considered. Three propellants were investigated: the triple base M31, and two composite propellants, JA2 and the developmental propellant LCT. For ever ... |
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