Download or read book Blast Overpressure Studies with Animals and Man Nonauditory Damage Risk Assessment for Simulated 155mm Self Propelled Howitzer Blast written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was undertaken to establish the nonauditory injury subthreshold in a simulated muzzle blast environment like that produced when tiring an M109 155 mm self-propelled howitzer (SPH) with one or more hatches open. An explosively driven shock tube, the hull of an M108 SPH, and a six-plate reflector system were used to produce the required muzzle blast signature. Using as many as 40 anesthetized sheep for each exposure condition, safe no-injury levels were established with an occasional minor upper respiratory tract lesion. These levels were 24 kPa for 6 blasts and 20 kPa for 25 to 100 blasts.

Download or read book Blast Overpressure Studies Part II Nonauditory Damage Risk Assessment for Simulated Weapons Fired 100 Times from an Enclosure written by Barbara Merickel and published by . This book was released on 1997 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anesthetized sheep were exposed to a reverberant wave environment like that produced from firing an antitank weapon from a room. The simulation was accomplished by detonating C4 explosives outside a chamber of 18.2 m3 volume. The blast wave traveled into the chamber through a 20-cm I.D. tube and was reflected off the back wall and subsequently throughout the chamber. The resulting waveform very closely approximated that generated by a Carl-Gustav antitank weapon fired from a chamber. Part I of the studies indicated that for a series of 1 shot or 3 shots, 2.5 minutes apart, multiple shots have a strong additive effect, decreasing the subthreshold levels. The subthreshold for a single blast was estimated to be above a peak of 48 kPa. The subthreshold for 3 exposures was estimated to be at 44 kPa. This study, called Part II, used 100 shots, 1 minute apart. For this exposure, a subthreshold peak of at least 23 kPa was verified using 19 animals.

Download or read book Blast Overpressure Studies Nonauditory Damage Risk Assessment for Simulated Muzzle Blast from a L2Omm Ml2l Mortar System written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was undertaken to establish the subthreshold, threshold, and suprathresholds for nonauditory injuries in a simulated muzzle blast environment like that produced when firing a 120mm M121 mortar system. A vertical axis explosively driven shock tube, in combination with reflector shields, was used to produce the required muzzle blast pressure-time pattern. Varying numbers of anesthetized sheep were subjected to 6 or 50 blasts of simulated muzzle blast waves in 1.5- to 3.0-dB increments. The results of the study demonstrated that sheep could be exposed to Pmax levels consisting of 6 blasts of 36 kPa each and 50 blasts of 30 kPa each and sustain no injuries to trivial upper respiratory tract injuries at most. Threshold injuries were calculated to occur at 53 and 34 kPa for 6- and 50-blast exposures, respectively. Suprathresholds for URT and GI tract lesions were predicted to be 69 and 46 kPa for 6 and 50 blasts each. A suprathreshold for lung hemorrhage was predicted at 277 kPa for 6 exposures. Comparative analyses of this study with previous complex wave studies demonstrated that the safe nonauditory subthreshold for as many as 100 complex blastwave exposures was 22 kPa.

Download or read book Simulation of Suicide Bombing written by Zeeshan-Ul-Hassan Usmani and published by iUniverse. This book was released on 2011 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces BlastSim - a physics-based simulation platform to model and simulate suicide bombing events. The BlastSim software is designed to test, analyze, and validate the results of different explosive and injury model combinations under various conditions with different sets of parameters, such as explosive and crowd formation characteristics, blockage and human shielding effects, fragmentation and shrapnel, and the bomber's position in 2- and 3-dimensional environments. The suicide bombing event can also be re-created for forensic analysis. The number of fatalities and injured after a suicide bombing event can be predicted using this software with 91% accuracy. The assessment of an explosion's effect on a crowd can lead to better management of disasters, triage of patients, locating blast victims under the debris, development of protective gear, and safe distance recommendations to reduce casualties.

Download or read book Blast Overpressure Studies with Animals and Man Task Order 1 Firing from a Bunker Simulator Study Task Order 4 Nonlinear Plug Study written by and published by . This book was released on 1996 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: To satisfy the Army's need for realistic safe limits for heavy weapon noise while wearing hearing protection, a 2-1/2 year study was undertaken. Using active duty military volunteers, 64 subjects established that the auditory system could be adequately protected with the RACAL(registered) muff from one to three exposures of the reverberant waveforms obtained from a rocket launcher out of an enclosure. Thus, nonauditory considerations set the exposure limits for this type of waveform. This research was accomplished under Task Order 1. Using 27 subjects, two types of nonlinear (increasing attenuation with level) plugs type of hearing protection were evaluated using 6 to 100 exposures of a freefield waveform of 1.5-ms duration. With the limited number of subjects, neither plug was proven adequate to protect the auditory system from this type of waveform. Several subjects had a temporary threshold shift (TTS) of their hearing of more than 25 dB. The compressible foam plug, did appear to provide adequate protection up the auditory limits for this waveform. This research was accomplished under Task Order 4.

Download or read book Web Intelligence and Intelligent Agents written by Zeeshan-Ul-Hassan Usmani and published by BoD – Books on Demand. This book was released on 2010-03-01 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a unique and diversified collection of research work ranging from controlling the activities in virtual world to optimization of productivity in games, from collaborative recommendations to populate an open computational environment with autonomous hypothetical reasoning, and from dynamic health portal to measuring information quality, correctness, and readability from the web.

Download or read book Modeling of the Non Auditory Response to Blast Overpressure written by James H. Stuhmiller and published by . This book was released on 1987 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this project is to develop mathematical models of the physical processes that cause blast injury so that the results of tests using animals in simple blast environments can be safely translated to estimating hazard to man exposed to blast both in the free field and within enclosures. The present project builds upon earlier work to develop models of the mechanics of the thorax and lung exposed to simple blast waves. The scope of activity has been expanded to include the lung, the gastro-intestinal track, the upper respiratory tract, and the tympanic organs. In addition, the work now addresses occupational and combat level exposures. This report covers the second year of the contract. A considerable amount of progress has been made in understanding the basic mechanisms of injury and in providing practical tools for the measurement and prediction of blast effects. Keywords: Blast overpressure, Injury, Modeling.

Download or read book Blast Overpressure Studies with Animals and Man written by and published by . This book was released on 1993 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Army needs realistic safe limits for exposure to impulse noise produced by heavy weapons. Impulse noise limits, based on data from small arms, may be overly conservative. In order to define new limits for heavy weapons, this systematic 5-year study of the effects of high-intensity impulse noise on human volunteers was undertaken. The number of impulses, the peak pressure levels, and spectral distributions of energy of heavy weapon-like impulses were varied systematically. Five major groups of 273 volunteers were given a series of exposures to one of three impulse types and to three types of hearing protection. The impulse spectrum was varied by changing the distance between the volunteer and an explosive detonation. The peak pressure level was varied in 3-dB steps by changing the weight of the explosive charge. The number of impulses per day was 6, 12, 25, 50, or 100. Volunteers wore hearing protection for all exposures. After each exposure, the amount of TTS, if any, was determined. Each volunteer started with an exposure of six impulses at the lowest intensity. If the TTS was less than 15 dB, the subject received six impulses at the next higher level the next day. Noise induced hearing loss, Temporary threshold shift of hearing(TTS), RA III, Volunteers.

Download or read book A Health Hazard Assessment for Blast Overpressure Exposures Subtitle Biological Response to Blast Overpressure A Summary of Modeling written by and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A soldier in training is exposed to a variety of blast sources that can adversely affect his auditory and nonauditory systems. While auditory standards have been formulated for many decades, knowledge about nonauditory effects of blast have not been captured in a criteria that can be applied to all circumstances. For the past 15 years, JAYCOR, working together with the Walter Reed Army Institute of Research, has been using modeling, simulation, and data analysis to determine the nature of injury in animal models, capture that understanding in physiologically correct mathematical models, and extend the findings to objective criteria that can be used to set exposure limits. This paper summarizes the accomplishments of that effort.

Download or read book Modeling of the Non Auditory Response to Blast Overpressure Considerations in Developing a Mechanistically Based Model of Blast Induced Injury to Air Containing Organs written by and published by . This book was released on 1990 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to anticipate the potential for injury in a wide variety of blast environments, without the excessive use of animal tests, it is necessary to develop a mechanistic understanding that can be used reliably. The process by which the blast wave produces injury is conceived to have the following intermediate steps. The external blast creates a pressure load distribution on the body that sets it in mechanical motion. That motion is transmitted through the body structure to the air-containing organs, where rapid distortions cause stresses within the organ tissue. The combination of stress and motion does work on the tissue and, when certain material limits are exceeded, results in injury. Multiple, isolated exposures lead to a nonlinear accumulation of damage. This paper discusses the non-organ-specific aspects of modeling this process and demonstrates that the general characteristics of injury observed in animal field tests can be explained. Injury to the larynx is used to make a quantitative validation and a simple-wave, multiple-short Damage-Risk Criterion (DRC) is developed. Keywords: RA 3, Non-auditory response, Blast overpressure, Protective equipment, Weapons effects(Biological), DRC, Larynx, Air-containing organs, Stress(Physiology).

Download or read book Modeling of the Non Auditory Response to Blast Overpressure Use of Surrogate and Analytical Models to Understand the Parameters Controlling Blast Injury to the Gastro Intestinal Tract written by James H. Stuhmiller and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous experimental studies using excised, perfused rabbit intestine in a sealed water tank, have provided direct visual observation that air bubbles produce local, violent, intestinal wall motion when they collapse under blast loading and that injury directly correlates with those motions. Measurements of the pressure within the bubble was shown to correlate with the motion of the wall and with injury. It was speculated that this pressure is an indirect measure of the stress in the wall tissue and therefore could be a means of quantifying the injury process. An analytical model of the dynamics of a bubble within an elastic membrane has been developed. Surrogate models, using materials with properties similar to that of intestine wall, but arranged in simpler geometric configurations, have been used to collect data on the dynamic process. The model results are compared and discussed. Keywords: RA 3, Weapons effects(Biological), Non-auditory responses, Blast overpressure, Explosions, G.I. Tract, Blast injury. (JG).

Download or read book Modeling of the Non Auditory Response to Blast Overpressure Summary of Blast Overpressure Field Data written by and published by . This book was released on 1990 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report is a compilation of blast overpressure field data taken at the Blast Overpressure Test Site in Albuquerque, New Mexico. The work was conducted under the direction of Dr. D.R. Richmond and a complete list of source documents is contained in the Reference section. Most of the field tests involved sheep placed in the blast environment. The purpose was to empirically correlate injury to blast wave parameters. This report summarizes the test data compiled to date, but is by no means all inclusive. Corresponding to each test are plots of the associated incident pressure field. The purpose of this report is to provide a convenient summary of these tests for use by all researchers. This report is organized into seven sections, each devoted to a different blast study. They are: Armored Personnel Carrier (APC); Bunker Summer Studies of 85, 86, 87; Double Peak; and Iso-Impulse. Within each section, a separate page describes each combination of charge type, charge weight, height of burst, and range. Keywords: RA 3, Weapons effects (Biological), Non-auditory responses, Blast overpressure, Explosions, Blast injuries, Field data, Tables(Data).

Download or read book Modeling of the Non Auditory Response to Blast Overpressure The State of Modeling Blast Injury written by and published by . This book was released on 1990 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: To understand the importance of the findings of the modeling project and to appreciate the need for extending those ideas, it is necessary to review the state of knowledge of blast overpressure injury at the time that the modeling project was initiated and how the needs of Army have evolved. In the early 1980's, two methods existed for assessing blast overpressure injury: one, Military Standard 1474B (Ref. 1), for use in occupational situations, and the other, the Bowen curves (Ref. 2), for use in combat conditions. Mil. Std. 1474-B is a standard developed for predicting auditory hazard based on observed values of peak pressure level and duration. It contains the so-called 'Z-line, ' above which no soldier should be exposed because of possible nonauditory injury that no amount of hearing protection could prevent. The nature of that injury is unspecified and the curve was not based on any observational data, although it might have reflected the intuition of the committee. The other curves in the standard were based primarily on small calibre weapons and, at the time of its creation, the Z-line was well removed from any operational weapon system.

Download or read book Modeling of the Non Auditory Response to Blast Overpressure Calculation of the Internal Mechanical Response of Sheep to Blast Loading written by and published by . This book was released on 1990 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calculations are made of the intrathoracic pressure expected from blast loading of sheep. A mathematical model of the chest wall and lung parenchyma have been formulated as a system of differential equations which include the effects of chest wall mass and resistance, density of the parenchyma and an adiabatic equation of state for air within the parenchyma. The differential equations are discretized as a system of nonlinear finite difference equations with the blast loading appearing as a boundary condition. This finite system is then solved on a computer using an implicit solution algorithm. Blast loadings used in the calculations are from field tests and correspond to animal response ranging from no injury to severe injury. Intrathoracic pressure in the esophagus and at four locations within the lung parenchyma, all in the approximate plat of the seventh thoracic vertebra, are compared with field test measurements for four occupational levels and four injury levels of blast overpressure. Keywords: RA 3, Numerical analysis, Differential equations, Weapons effects(Biological), Blast injuries, Non- auditory responses to blast overpressure, Thoracic injury.

Download or read book A Proposal to Build a Laboratory Blast Overpressure Test Simulator Subtitle The Development of a Water Jet Impactor written by J. H. Y. Yu and published by . This book was released on 1982 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: In order to establish a damage risk criteria (DRC) on pulmonary and gastrointestinal injury for the operating crew who fire heavy artillery, direct information that links the critical blast overpressure parameters and the degree of injury is necessary. Although field tests can be performed to provide the data, they are not amenable to speedy post-mortem analyses and sophisticated instrumentation. A laboratory test facility that is capable of generating the equivalent blast overpressure signal would serve the purpose and greatly facilitate the test procedure. It would also help to provide an environment for systematic and controlled experiments to quantify the relationship between blast and injury. However, for various reasons, most conventional approaches in generating the blast overpressure or its equivalent were not suitable for a laboratory setting. The idea of using a jet impactor to generate the impact signal was conceived. This report summarized the process of the development of such an apparatus. The first part focuses on the proof of the principle and identification of key elements and parameters. The second part is mainly devoted to the design and development of the prototype system.

Download or read book A Health Hazard Assessment for Blast Overpressure Exposures Subtitle Use of Animal Test Data in the Development of a Human Auditory Hazard Criterion for Impulse Noise Part 2 written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A health hazard assessment for blast overpressure exposures is presented.

Download or read book Injury Assessment for Blast Overpressure Effects written by M.J. van der Horst and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: