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361.
Robert E. Markland L. Douglas Smith Jack D. Becker 《Journal of the American Water Resources Association》1976,12(3):577-600
ABSTRACT This paper describes the development and use of a mixed integer programming model for the planning of land disposal wastewater treatment facilities. Consideration is given to relevant construction and operating costs for land sites, transmission arteries, land acquisition costs, tangible benefits from land use, controls on aquifers, and various other engineering and technical constraints The model is used to determine which land disposal sites should serve which treatment plants, when initial construction should be initiated and completed, and when capacity expansion should occur. The model's application to the St. Louis Standard Metropolitan Statistical Area is illustrated and discussed. 相似文献
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Vegetation changes associated with barrier-dune construction on the outer banks of North Carolina 总被引:1,自引:0,他引:1
Manmade dunes are used to stabilize the barrier islands of the mid-Atlantic coast of the United States so that they are more amenable to development. Although this strategy has stabilized extensive sections of the barrier-island substrate, it has also caused significant ecological changes. The rate and pattern of the resulting vegetation changes along the Outer Banks of North Carolina were determined using sequential aerial photography. Successional trends have been altered in favor of more stable woody communities. 相似文献
366.
Irreversible environmental changes are occurring along the Colorado River in the Grand Canyon as a result of regulation of the river flow by the Glen Canyon Dam. The questions of primary importance in managing this great natural resource are 1) in what manner and how rapidly are the physical and ecological adjustments taking place, and 2) is the increased use of the river for recreational boating contributing to the degradation? Human use along the Colorado River is limited, for the most part, to the relic, pre-dam fluvial deposits colloquially called “beaches.” With the new river regime these deposits are positioned well above the present high-water stage, 27,000 cubic feet/second (cfs), or 765 cubic meters/second (cms), so they are not replenished periodically as they were prior to construction of the dam in 1963. The dominant natural processes now are aeolian sand transport and mass wasting. The float-trip passengers use the river beaches for hiking, camping, and. lunch stops. At the most desirable sites thirty to forty people camp on the beaches each night over a four to five month season. Human impact includes incorporation of campsite litter, burial of chemically treated waste, and the direct stress associated with people walking on the vegetation and unstable sedimentary deposits. Results of our investigations indicate that the rate of degradation at the most heavily used sites exceeds the capacity of aeolian processes to reestablish natural landscapes. Therefore, careful management of float trjps is needed if these environments are to be maintained in a natural state rather than a “sand-box” state. 相似文献
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The authors present an economic justification for extramarket intervention in the markets for secondary materials and briefly discuss the possible impacts of futures trading on the cash market for a commodity. These impacts are applied to the markets for secondary materials and the potential effects are assessed. They conclude with a rationale for public participation in initiating a scrap futures market. 相似文献
368.
Robert C. Baron 《The Environmentalist》1982,2(2):133-141
Summary The growth in the application of computers is one of the major developments of the last half of the 20th Century. There have
already been substantial changes in society because of the computer, but even greater changes lie ahead. This paper defines
some of the characteristics and applications of computers, as well as some of their limitations. It closes with comments on
the implications of the development of ‘a new class of illiterates’—those who are unfamiliar with or even afraid of the computer
as an aid in measurement, analysis, record keeping, communication and education.
Robert C. Baron has over 25 years experience in the computer industry, as an engineer and as an executive. He was program
manager for the Mariner II (Venus) and the Mariner IV (Mars) on board space computers. He was worldwide systems manager for
Honeywell's minicomputer business. In 1972, he founded Prime Computer and was its first president. He is currently working
as a writer, lecturer and consultant on the development and application of computer and communication technology. Mr. Baron
is the author or contributor to six books and has written over 40 papers and speeches. 相似文献
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