Download or read book Determinations of Aerodynamic drag Parameters of Small Irregular Objects by Means of Drop Tests written by and published by . This book was released on 1961 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the 1955 and 1957 Test Operations at the Nevada Test Site (NTS), masses and velocities were determined for more than 20,000 objects, such as glass fragments from windows, stones, steel fragments, and spheres, which were energized by blast winds resulting from nuclear explosions. Following the field tests, a mathematical model was devised to help explain quantitatively the experimental results. This model required certain aerodynamic-drag information in regard to the displaced objects. It was the purpose of the study outlined in this report to determine the necessary drag properties for the objects by means of drop tests. In addition to the objects mentioned above, small laboratory animals, mice, rats, guinea pigs, and rabbits, were used in the drop tests.
Download or read book Blast induced Translational Effects written by E. Royce Fletcher and published by . This book was released on 1966 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mathematical model was developed to predict the time displacement histories of objects translated by the blast winds from conventional or nuclear explosions; these predictions were then compared to actual experiments. The objects studied varied in size from 139 mg spheres to man and were all assumed to be free to move over a smooth horizontal surface. The effects of ground friction could either be included or neglected, but when they were considered the ground friction eventually brought the objects to rest after the winds had passed. The values of ground friction used were determined experimentally and were found to be functions of the velocity and mass of the object being displaced. The translational model was general enough for either classical or nonclassical blast waves to be considered. Results for a chemical explosion were obtained by using both the computed blast waves of various authors and the experimentally determined blast waves. These predicted results were compared with each other as well as with experimental data obtained with steel spheres. The model was used to determine dynamic pressure impulses necessary to explain the measured sphere velocities at three ranges from ground zero. Another mathematical model was briefly described which was developed to compute the detailed two-dimentional trajectories of objects as they roll, slide, and bounce along the ground. The model closely predicted the measured distances between bounces and the total displacements of concrete blocks and large stones and thus helped to explain the mechanisms of tumbling by which an irregular object may become airborne during both the accelerative and the decelerative phases of displacement.
Download or read book Biological Tolerance to Air Blast and Related Biomedical Criteria written by Clayton S. White and published by . This book was released on 1965 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experience with animals exposed in a variety of above and below ground structures during full-scale field operations at the Nevada Test Site in 1953, 1955 and 1957 were reviewed. The data were assembled and summarized to illustrate the nature of the blast-induced problems of significance in protective shelters, "open" as well as "closed". Potential hazards were related to the following: various patterns of variation in environmental pressure; translational events associated with transient, high-velocity winds, ground shock and gravity involving the impact of energized inanimate objects on the one hand the the consequences of whole-body displacement on the other; non-line-of-site thermal phenomena including hot objects and rapidly moving hot, dust- laden air and debris; and dust, in the respirable size range, sufficiently high in concentration even in "closed" shelters as to warrant design measures to minimize or eliminate the occurrence of small particulates whether arising from wall spalling or otherwise. Tentative biological criteria, conceived to help assess human hazards from blast-related phenomena, were presented. Relevant data from the literature and on- going research in environmental medicine were set forth to aid the reader in appreciating how the criteria were formulated, what information was extrapolated from animal data, and wherein "best estimates" were employed. "State-of-the-art" concepts were noted to emphasize areas in which more thinking and research must continue if more refined, complete and adequate criteria are to be forthcoming for assessing man's response to blast-induced variation in his immediate environment.
Download or read book Technical Concept written by John A. Auxier and published by . This book was released on 1962 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mobile Radiological Measuring Unit written by Zolin G. Burson and published by . This book was released on 1965 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ichiban written by John A. Auxier and published by . This book was released on 1964 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Radiation Measurements in Conventional Structures Comparison of measurements in above ground and below ground structures from simulated and actual fallout radiation written by Zolin G. Burson and published by . This book was released on 1964 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ground Roughness Effects on the Energy and Angular Distribution of Gamma Radiation from Fallout written by Charles Martin Huddleston and published by . This book was released on 1964 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tertiary Blast Effects written by Donald R. Richmond and published by . This book was released on 1961 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: A total of 455 mice, rats, guinea pigs and rabbits were subjected to impact at velocities ranging between 25 ft/sec and 51 ft/sec. The desired velocities were generated by allowing the animals to free-fall from various heights to a flat concrete pad. The ventral surface of each animal was the area of impact. Probit analyses of the 24-hr mortality data yielded LD50 impact velocities with 95 per cent confidence limits as follows: mouse, 39.4 (37.4-42. 0) ft/sec; rat, 43.5 (42.0 - 44.8) ft/sec; guinea pig, 31.0 (30.0 - 31.9) ft/ sec. The LD50 figures for the mouse and rat were significantly higher, statistically, than those for the guinea pig and rabbit. The small spread in the LD50 values suggested little variation in the tolerance of biological systems to impact. Further, the steepness of the mortality curves indicated a narrow survival range to impact. Extrapolation of the experimental data to the 70 kg animal yielded a predicted LD50 impact velocity of 26 ft/sec (18 mph). Literature relevant to the human case was reviewed and the tentative applicability of the predicted figures to adult man was discussed. (Author).
Download or read book Extended and Point source Radiometric Program written by Francis John Davis and published by . This book was released on 1962 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extended-source calibration area was set up in the Nevada Test Site area to encourage a standardization of airborne radiometric instrumentation among several government agencies. and private companies. A simulated plane-source array was laid out with positions at 100-ft intervals in the form of a square 2000 ft on a side. For ground measurements a smaller square array of 100 positions at 10-ft intervals was placed in the center of the large array. Two sets of sources were used in the array. Cobalt-60 and cesium-137 sources of 4.5 and 15 mc, respectively, were available for the large array and sources one hundredth of these values in the smaller array. Point sources of Co(exp 60), Cs(exp 137), and I(exp 131) of the order of 2 curies each were available for comparison with the area sources. Measurements 3 ft above the area sources indicated 200 micronr/hr for Co(exp 60) and 225 micronr/hr for Cs(exp 137). Four government agencies and one private company participated in an intercalibration exercise during November 1960. Various types and sizes of aircraft from a Cessna 172 to a Douglas Dc-3 were used. Various instrumentation devices, mostly scintillation type detectors, were tested. Flights ranging from 100- to 1000-ft altitude included background measurements, instrument calibration, intercalibration, proof-testing equipment, comparison of point- and area-source measurements, measurements of air attenuation and buildup of gamma radiation, and gamma-ray spectral measurements.
Download or read book The Effects of Nuclear Weapons written by U.S. Atomic Energy Commission and published by . This book was released on 1964 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Nuclear Weapons written by Samuel Glasstone and published by . This book was released on 1962 with total page 750 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Nuclear Weapons written by United States. Department of Defense and published by . This book was released on 1964 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Nuclear Weapons written by United States. Defense Atomic Support Agency and published by . This book was released on 1962 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Evaluation of the Radiation Protection Provided by an Earth covered Shelter written by Zolin G. Burson and published by . This book was released on 1962 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study was undertaken to determine the protection against fallout radiation provided by an earth-covered shelter. The study indicated that the shelter offered excellent protection from fallout radiation deposited on and around the shelter. This study also added additional data to the research in radiation shielding provided by various structures which is being conducted by the Civil Effects Test Operations, Division of Biology and Medicine, U.S. Atomic Energy Commission. A fallout radiation field was simulated by pumping, at constant speed, a sealed Co60 source through a long length of tubing which was evenly distributed over an area. Radiation measurements were made Inside the shelter by dose-integrating ionization chambers. In general, the results indicated that the protection factor (ratio of the open-field exposure dose rate to the exposure dose rate in the structure) was approximately 5000 in the center of the shelter, increasing to 10,000 to 15,000 along the sides, and decreasing to about 3000 near the ends. Directly below vents the protection factor was found to be approximately 2500 at the 3-ft level. The shelter was a half-round corrugated-steel structure covered by a minimum of approximately 2 ft of earth on the top and 5 to 7 ft of earth on the sides.
Download or read book Operation Plan and Hazards Report Operation Bren written by F. W. Sanders and published by . This book was released on 1962 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Other selected programs that can utilize the radiation fields available on a non interference basis are included as parts of the Operation. Descriptions of the HPRR and the Co60 source, their operating procedures, the manner in which they will be used, and possible hazards are included.
Download or read book Experimental Evaluation of the Fallout radiation Protection Afforded by a Southwestern Residence written by Z. Burson and published by . This book was released on 1962 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was conducted to determine the fallout-radiation protection afforded by a residence representative of a type of construction much in favor in the Southwest: a single-story stucco and frame house with a heavy shake roof and no basement. This study was one of many such studies sponsored by Civil Effects Test Operations, Division of Biology and Medicine, U. S. Atomic Energy Commission, for the purpose of evaluating the protection presently afforded by ordinary homes and structures against the dangers of fallout radiation. The protection afforded by the home was determined by simulating a fallout-radiation field above and immediately surrounding the house and measuring the radiation level within. The radiation field was simulated by pumping a sealed Co(60) source through a long length of tubing evenly distributed over the test area. Highly sensitive dose-integrating ionization chambers were used to measure the radiation level inside the structure. The test was performed rapidly, easily, and safely. Valid statistical data were obtained even though the radiation level was of such low magnitude that it was unnecessary to evacuate any of the neighboring homes. The protection factors within the house (ratio of exposure dose rate in the open field to exposure dose rate in the structure) ranged from 2.8 to 4.4, depending on the location. The results compare favorably with those found in previous exercises under similar conditions.
