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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

INSTRUMENTED BALLISTIC TEST PROJECTILE

Flyash, Boris, Platovskiy, Steve, Cantatore, Dominick 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / For years, ballisticians have been studying the phenomena associated with cannon launched projectiles. In particular, is the study of the pressure internal to the cannon and about the base of the projectile during cannon launch through muzzle exit. Pressure on the base is thought to be uniform and therefore hydrostatic, even though there are undulations in the magnitude of the pressure from the burning propellant. This paper studies various phenomena of the launching of 155-mm artillery projectiles with slip band obturators. Specifically, pressure gradients in and around the base and pressure along the body caused by obturator “blow-by” during the interior ballistic flight and muzzle exit. This study is accomplished by use of two different types of Instrumented Ballistic Test Projectiles (IBTP). The objective of tests performed was to successfully capture pressure and acceleration live data which will be used to characterize the localized base and body pressurization on a 155-mm artillery cannon launched projectile. The telemetry system used for these tests was the ARRT-124 telemetry system provided by the Armament Research, Development, and Engineering Center, specifically the Precision Munitions Instrumentation Division. The telemetry system used for the IBTP employs a traditional FM/FM technique for monitoring and transmitting a number of analog channels. Preliminary captured data indicated localized fluctuations in pressure that are not uniform over the base and the projectile body. Further studying of the data may provide insight into other projectile dynamics such as fin deployment, set forward accelerations at muzzle exit, and obturator performance.
12

United States Air Force precision engagement against mobile targets is man in or out? /

Kosan, Keith J. January 1900 (has links)
Thesis--School of Advanced Airpower Studies, Maxwell Air Force Base, Ala., 1999-2000. / Title from title screen (viewed Oct. 28, 2003). "November 2001." Includes bibliographical references.
13

Establishment of a vaporous Hydrogen Peroxide bio-decontamination capability

McAnoy, Andrew M. Sait, Michelle. Pantelidis,Sue. January 2007 (has links)
Mode of access: Internet via World Wide Web. Available at http://hdl.handle.net/1947/8654. / "February 2007"
14

ELECTROCHEMICAL REDUCTION OF MUNITIONS WASTEWATER-BENCH SCALE AND PILOT SCALE STUDIES

DOPPALAPUDI, RAJESH BABU 08 November 2001 (has links)
No description available.
15

ADVANCEMENTS IN TRANSMITTER HARDWARE FOR WIRELESS TELEMETRY ENGINEERS

Burke, Larry, Osgood, Karina, Muir, John, Dearstine, Christina, Cardullo, Micheal, Fox, Timothy 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / M/A-COM has developed a chip set designed specifically for miniaturized ballistic telemetry applications. One key component of this chip set is a dual port voltage controlled oscillator (VCO). This device allows for independent optimization of both modulation and tuning parameters at the chip level. In the dual port architecture, the modulation port of the VCO may be tailored for the peak (frequency) deviation requirements of each system, while still permitting the device to tune over entire SLOWER band. Additionally, M/A-COM has developed S band power amplifiers (PAs) for medium power (500mW, 1W and 2W) telemetry applications. These new PAs are very efficient, (>45% PAE) when operated in saturation. This improved efficiency means these components may be integrated into transmitters with a miniaturized form factor. The excellent thermal performance of these new PAs allows them to be packaged in commercial plastic packages which are robust in high shock/high vibration applications. This paper reviews the design of each MMIC device and presents system performance data.
16

Design and Implementation of an Inertial Measurement Unit (IMU) for Small Diameter Ballistic Applications

Bukowski, Edward F., Brown, T. Gordon 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The US Army Research Laboratory currently uses a variety of ballistic diagnostic systems for gathering aerodynamic information pertaining to gun launched munitions. Sensors are a vital component of each of these diagnostic systems. Since multiple sensors are commonly used, they are often configured into a sensor suite or inertial measurement unit (IMU). In order to gather information on smaller diameter projectiles, a small diameter IMU was designed using commercial-off-the-shelf (COTS) sensors and components. This IMU was first designed with a 21.6mm diameter and then later reintegrated into a 17.5mm diameter unit. The IMU provides up to ten sensor data channels which can be used to make in-flight projectile motion measurements. These measurements are then used in the determination of the projectile's aerodynamics. It has been successfully flight tested on a variety of projectiles. It has been used in conjunction with an on-board recorder (OBR) to take measurements on 40mm and 25mm projectiles. It has also been used in a telemetry based system on-board a flare stabilized 25mm projectile. This paper covers the design of the IMU and gives examples of various sensor data.
17

A TRANSMITTER CHIP SET FOR WIRELESS TELEMETRY APPLICATIONS

Osgood, Karina, Moysenko, Andy, Webb, Amy, Schneider, Dennis, Colangelo, Ronald, McMullen, Kenneth, Wert, Robert, Muller, Peter 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / M/A-COM, Inc. has developed a highly integrated transmitter chip set for wireless telemetry applications under a U.S. Army Development Contract. The chip set is comprised of a voltage controlled oscillator (VCO), a silicon synthesizer/phase locked loop (PLL), and a family of power amplifiers (PA's). The chip-set is designed to operate over the military L and S Band frequencies as well as the lower commercial ISM band. Using these components, M/A-COM has produced IRIG compliant transmitter modules for ballistic telemetry applications. These modules have been successfully flight tested by the Army Research Laboratory at Aberdeen Proving Ground, Maryland. This paper reviews the transmitter system architecture and presents test data for the transmitter module and individual components.
18

Decision criteria for the use of cannon-fired precision munitions

La Rock, Harold L. 06 1900 (has links)
The U.S. Army and Marine Corps are developing guided munitions for cannon artillery. These munitions provide a significant increase in range and accuracy, but the tactics, techniques, and procedures used to employ them have yet to be developed. This study is intended to assist with that development by providing a method to determine when to use these munitions rather than conventional munitions in order to achieve a tactical-level commander's desired objectives. A combination of multi-attribute utility theory and simulation are used to determine the best ammunition (precision or conventional) to fire under certain battlefield conditions. The simulation, developed by the U.S. Army Research Laboratory, provides results on the full range of artillery effects by varying the different battlefield conditions that have the greatest effect on the accuracy of artillery. The results of simulated artillery fire missions are studied to determine the combination of battlefield conditions that produce the best results for each type of ammunition. A decision model is used to account for a commander's expected preferences based on tactical considerations. The results vary greatly depending on the battlefield conditions and the commander's preferences. One type of projectile does not clearly dominate the other.
19

Biotransformation and photolysis of 2,4-dinitroanisole, 3-nitro-1,2,4-triazol-5-one, and nitroguanidine

Schroer, Hunter William 01 May 2018 (has links)
Nitroaromatic explosives have contaminated millions of acres of soil and water across the globe since World War II with known mutagenic, carcinogenic, and ecotoxicological effects. Recently, the U.S. Army initiated a shift away from traditional explosive compounds, such as trinitrotoluene (TNT) and hexahydrotrinitrotriazine (RDX), towards new, insensitive high explosive formulations. The new formulations approved for use include “IMX-101” and “IMX-104,” which contain 2,4-dinitroanisole (DNAN), 3-nitro-1,2,4-triazol-5-one (NTO), and nitroguanidine (NQ). These mixtures are less prone to accidental detonation making storage, transport, and implementation of these formulations safer for soldiers. Furthermore, initial research indicates that these compounds are less toxic than the older analogues. Despite the apparent benefits, the new explosives have higher solubility (approximately 3-300 times) than the compounds they are replacing, and NTO and NQ are fairly recalcitrant to aerobic biodegradation. The refractory nature and high solubility of the compounds raises concerns about leaching and water contamination considering the previous scale of environmental contamination from production and use of legacy explosives, while feasible strategies for cleaning up the new chemicals from soil and water have not been developed. Therefore, there is a critical need for understanding of the mechanisms of biodegradation these compounds will undergo in the environment and in engineered systems. In addition, a number of questions remain about the photochemistry of the compounds and how they may transform in sunlit surface water. Accordingly, this thesis examines biological transformations of DNAN and NTO in vegetative, fungal, and bacterial organisms, as well as photolysis of NTO and NQ in aqueous solution and DNAN in plant leaves. I identified 34 novel biotransformation products of DNAN using stable-isotope labeled DNAN and high resolution mass spectrometry. Most identified biotransformation products were the result of a nitro-group reduction as the first metabolic step. Arabidopsis plants, a Rhizobium bacterium, and a Penicillium fungus all further metabolized DNAN to produce large, conjugated compounds, and no mineralization was observed in the systems studied. All three organisms reduced both para- and ortho-nitro groups of DNAN, with a dramatic preference for ortho reduction. I found that photodegradation of DNAN and its plant metabolites within Arabidopsis leaves could impact the phytoremediation of DNAN and other contaminants. Soil slurries acclimated to nitroaromatic wastewater degraded DNAN with and without carbon and nitrogen amendments and NTO with added carbon. Organisms capable of degrading DNAN and NTO were isolated, and NTO was transformed to urea, amino-triazolone, and hydroxyl-triazolone. Photolysis of NTO sensitized singlet oxygen formation and yielded hydroxyl-triazolone, nitrite, nitrate, and ammonium. The rate of photolysis of NTO increased over the neutral pH range, and natural organic matter quenched the photolysis of NTO. An unknown volatile product accumulated in the headspace of sealed reactors after NTO photolysis. Singlet oxygen degraded NTO and formed nitrite in stoichiometric yield. Photolysis of NQ produced nitrite and nitrate, but at high pH, the reaction occurred much faster than at neutral pH, and the mass balance of inorganic nitrogen was much lower. Further work should be done to investigate the mechanisms of and products from NTO and NQ photolysis.
20

A Multidisciplinary Approach to the Identification and Evaluation of Novel Concepts for Deeply Buried Hardened Target Defeat

Branscome, Ewell Caleb 20 November 2006 (has links)
The objective of the work described was to identify and explore a paradigm shifting solution that could offer leap-ahead capabilities to counter current and future DBHT threats while mitigating or eliminating the self-deterrence issue. A multidisciplinary approach to the problem was formulated and implemented. Systematic evaluation of DHBT defeat alternatives lead to the selection of a thermal subterrene as a hypothetical means of providing such a capability. A number of possible implementation alternatives for a thermal subterrene were investigated, resulting in the identification of the RadioIsotope Powered Thermal Penetrator (RIPTP) concept for providing an effectively unlimited, self-contained hard rock penetration capability using near-term technologies. However, the proposed approach was novel and thus required formulation and application of a physics based multidisciplinary analysis code to enable evaluation of design alternatives and analysis of performance. The following disciplinary analyses were composed into a multidisciplinary analysis code for a RIPTP: packing of RIPTP components in available volume; close-contact melting analysis; transmutation of isotope species by neutron activation; reactor neutron economy; radioisotope power generation through decay; metamodelled radiation shielding calculations for a RIPTP; and steady state thermal analyses for a RIPTP in various scenarios. Performance analysis of the identified baseline Thulium-170 RIPTP suggested that the predicted low penetration rate of about 10 meters/day could be a significant negative factor with regards to possible viability of the concept. Consequently, a survey for potentially enabling technologies was performed using an adaptation of the Technology Impact Forecasting (TIF) approach. It was found that the greatest potential for improving performance of the baseline Thulium-170 RIPTP resulted from increasing overall power density of the penetrator. Several possible technology approaches to achieving significantly increased penetration rates are proposed.

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