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101.
T he technological prowess of the U nited S tates was symbolized by what became known as the space shuttle, which the National Aeronautics and Space Administration (NASA) began to work on in the late 1960s. With the shuttle program NASA planned to facilitate its aggressive space-exploration effort by providing low-cost, reusable transportation to and from Earth's orbit. NASA officials compared the space program's traditional use of expendable launch vehicles to throwing away a railroad locomotive after every train trip, whereas a reusable shuttle would offer cost-effective, routine access to space. Approval of the shuttle initiative required complex political maneuvering by NASA and its supporters between 1969 and 1972. The twists and turns in the approval process actually shaped the final direction that the shuttle program took, demonstrating the pitfalls of decision making by compromise and the challenges of managing large-scale technology programs within the federal government.1  相似文献   
102.
The measurement and interpretation of spatial economic structure have presented many problems for analysts. The notion of a spatial multiplier has received even less formal attention; part of the motivation for this paper is the examination of the degree to which sectoral decomposition analysis might prove useful in illuminating the paths of interaction across space that are associated with changes in exogenous activity levels. In this paper, we present three perspectives that examine spatial structure in the context of an aggregated interregional social accounting matrix for Bangladesh. These perspectives examine structure at the micro-, meso-, and macrolevels and are interpreted with the assistance of several alternative methods, including structural path analysis, the field of influence, the superposition principle, multiregional feedback loop analysis, and the Matrioshka Principle; the results are interpreted analytically and cartographically. Some attention is also devoted to the formulation of a general approach to spatial multipliers. It is shown that the structure of flows and the structure of influence reveal patterns that, taken together, provide important insights into an understanding of structure and may prove to form the basis for the eventual formal presentation of the spatial multiplier.  相似文献   
103.
Current federal hazardous and low-level radioactive waste management policies (under conjoint federalism) fail to balance national concerns for consistency with state concerns for equity, discretion, and adequate resources. Congress should expand conjoint federalism to permit states to charge differential fees on imported hazardous waste as it does for low-level radioactive waste. For low-level radioactive waste, clarification of the "take title" issue makes the present framework for state discretion implementable, given sufficient time.  相似文献   
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Nestorian Crosses from Jabal Berri   总被引:1,自引:1,他引:0  
Two small crosses, one of bronze and the other of mother-of-pearl, from the surface of a site near Jabal Berri in northeastern Saudi Arabia are presented. They are attributed to the Nestorian community of Bet Qatraye which is known from literary sources to have flourished during the Sasanian period.  相似文献   
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An important line of research concerning historical fertility patterns in currently developed countries of Europe has concluded that, prior to the fertility transition, marital fertility was essentially constant over time, and deliberate fertility control was virtually unknown. It has been argued that variations over time in overall fertility were largely the consequence of variations in nuptiality. Other researchers have challenged these views and present evidence for the existence of a significant minority of fertility controllers in pretransition populations. In this article, we find support for this second view and argue that (1) there was significant, non-random variation in marital fertility over time, prior to the transition; (2) in many cases, this variation in marital fertility was large relative to contemporaneous variations in nuptiality; and (3) in a substantial minority of the cases, the variation over time in pretransition marital fertility was so large that it is suggestive of deliberate fertility control. Thus, our findings question the view of fertility transition as an innovation in deliberate marital fertility control. While most of our evidence is based on data from England and Wales, we find corroboration of our key results in other European data.  相似文献   
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Accelerator mass spectrometry radiocarbon ages have been taken for a test suite of small samples of material removed from some of the ‘beeswax’art figures found in rock shelters in northern Australia. The results indicate that we can reliably date this unique form of rock art with no noticeable damage. We had not expected to find figures of any great antiquity, and so we were surprised to find that the ages obtained spanned the time period from the recent past to about 4000 BP.  相似文献   
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