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1. |
Determinism and randomness in fluvial geomorphology |
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Eos, Transactions American Geophysical Union,
Volume 60,
Issue 36,
1979,
Page 651-655
J. Samuel Smart,
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摘要:
During the past 20 years, a controversy, or at least a difference of opinion, has developed over the relative merits of deterministic and random models in fluvial geomorphology. A survey of the literature indicates that there are actually two distinct approaches that make use of stochastic concepts. As all three groups draw upon physical principles to a considerable extent, the origin and development of deterministic and stochastic disciplines in physics are reviewed and illustrated with some simple examples. The information obtained is then used to examine the scientific content of the claims put forward by the three groups and to make some judgment of their validity.Fluvial geomorphology involves the study of several complex and interrelated processes, such as chemical weathering, erosion, soil creep, sediment transport and deposition, development and maintenance of stream networks, and channel hydraulics. It is clearly very difficult to obtain detailed quantitative explanations of such processes. Consequently, a number of authors, beginning withLeopold and Langbein[1962], have proposed that stochastic methods could be used to advantage in many instances. During the past 20 years, a controversy, or at least a difference of opinion, has developed over the relative merits of deterministic and stochastic models in fluvial geomorphology.
ISSN:0002-8606
DOI:10.1029/EO060i036p00651
年代:1979
数据来源: WILEY
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2. |
A response to Wasson's views on cutting the Old Woman Meteorite |
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Eos, Transactions American Geophysical Union,
Volume 60,
Issue 36,
1979,
Page 652-652
Roy S. Clarke,
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PDF (1506KB)
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摘要:
Wasson has recently expressed his views about ways to ‘optimize both the scientific and exhibit value’ of the Old Woman meteorite (Eos, 60(28), July 10, 1979). This is a question that we at the Smithsonian Institution have had under active consideration for many months. I would like to answer his criticism of our plan by briefly describing the decision‐making process and outlining a little of the scientific and curatorial thinking behind it.The meteorite was found by two prospectors in 1976 in the Old Woman Mountains of Southern California. It was accessioned into the collections of the National Museum of Natural History in December of 1976 and arrived in Washington in March of 1978. Before and after its arrival, the meteorite was the subject of protracted litigation in the federal courts—which continues to this day—and of substantial political controversy abundantly discussed through the press. In late September of 1978, the way seemed clear to proceed with the study of the meteorite. Opinions were solicited by letter from members of the scientific and museum communities on the best approach to its study. Among those individuals with a history of productive research and creative curation of iron meteorites, whom I considered to be particularly well qualified to make a judgment, there was a strong consensus calling for a major cut through the meteorite to reveal as large a surface area as
ISSN:0002-8606
DOI:10.1029/EO060i036p00652-01
年代:1979
数据来源: WILEY
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3. |
Federal support of university R&D |
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Eos, Transactions American Geophysical Union,
Volume 60,
Issue 36,
1979,
Page 655-655
Anonymous,
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PDF (230KB)
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摘要:
To say that the federal government has a definitive policy in its actions to support university‐based scientific research and development would require more justification than was readily discernable from a recent briefing given to representatives of the AAU (American Association of Universities) by geophysicist and presidential science advisor, Frank Press, with a group of executive administrators of various agencies. However, there may be a recognizable trend occurring that is quite evident when the numbers are viewed. Clearly, there is a notable increase in funding for research done outside of the government, and in particular, by scientists in geophysics.For example, the National Science Foundation's overall request of more than $1 billion came through Congress unscathed for the first time in recent years. NASA's budget faired almost as well, even taking into account the huge and mounting costs of shuttle (but not taking into account future costly delays). Other agencies that appear to have had little budgetary problems with this Congress are the Departments of Defense, Interior, Energy, and Commerce, all of which spend most of their research dollars in house, with larger contractors, or with industry, but nonetheless also support a sizable portion of geophysical research done at universities. Other agencies, such as Agriculture and HUD, did not appear to have suffered serious reductions, although agencies that support biomedical and associated research seemed to have taken the largest cuts. The medical research cuts, however, were made by OMB, and as usual, were reinstated by Congres
ISSN:0002-8606
DOI:10.1029/EO060i036p00655-01
年代:1979
数据来源: WILEY
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