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21.
Robert Perry 《Policy Sciences》1972,3(3):349-359
A comparison of 20 years of aircraft production in Europe and America. U.S. cost increases in the system acquisition process have resulted in large part from unforeseen (sometimes unforseeable) engineering difficulties in the development phase, and from substantial production commitment before development was complete. Common European strategy completed basic development before beginning production and demonstrated utility through prototypes, using early proof-testing of engines, electronics and airframes. An alternative acquisition strategy to that used in the 1960s in the United States is recommended for the next decade: (1) incremental acquisition, based on a sequence of decision points and a succession of development and production phases; and (2) pronounced austerity in early development phases. These changes would result in lessened cost growth and lower U.S. acquisition costs, as well as in improved predictability of schedule and system performance outcomes.The following statement was prepared for the Committee on Armed Services, United States Senate, and was presented on December 7, 1971. 相似文献
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Public Choice - I apply Tullock’s transitional gains trap to the formalization of property titles in Latin America to understand public choice problems in mending institutions. In an area... 相似文献
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This research explored the feasibility of using the degradation rate of deoxyribonucleic acid (DNA) in human rib bone to determine the time interval since death. Postmortem human rib samples were surface sterilized and incubated under sterile conditions in either high or low humidity conditions at room temperature for a period of weeks. At selected times, portions of the bone were cut away, and the DNA from these samples was extracted and subjected to strand separating gel electrophoresis. The DNAs in the gels were transferred to a nylon membrane, preserving their relative positions as in the gel, and probed with radioactive total genomic human DNA. Autoradiograms produced were scanned and digitized. When the samples were incubated under identical conditions, the degradation rate of DNA in samples from different individuals appeared very similar. The DNA degradation rate may vary with temperature and humidity more than it varies between individuals. 相似文献
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