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31.
Bruce J. Blanchard Marshall J. McFarland Thomas J. Schmugge Edd Rhoades 《Journal of the American Water Resources Association》1981,17(5):767-774
Large area soil moisture estimations are required to describe input to cloud prediction models, rainfall distribution models, and global crop yield models. Satellite mounted microwave sensor systems that as yet can only detect moisture at the surface have been suggested as a means of acquiring large area estimates. Relations previously discovered between microwave emission at the 1.55 cm wavelength and surface moisture as represented by an antecedent precipitation index were used to provide a pseudo infiltration estimation. Infiltration estimates based on surface wetness on a daily basis were then used to calculate the soil moisture in the surface 0–23 cm of the soil by use of a modified antecedent precipitation index. Reasonably good results were obtained (R2= 0.7162) when predicted soil moisture for the surface 23 cm was compared to measured moisture. Where the technique was modified to use only an estimate of surface moisture each three days an R2 value of 0.7116 resulted for the same data set. Correlations between predicted and actual soil moisture fall off rapidly for repeat observations more than three days apart. The algorithms developed in this study may be used over relatively flat agricultural lands to provide improved estimates of soil moisture to a depth greater than the depth of penetration for the sensor. 相似文献
32.
Harold E. Marshall Rosalie T. Ruegg 《Journal of the American Water Resources Association》1976,12(5):903-917
ABSTRACT: The Environmental Protection Agency administers a construction grant program to encourage abatement of wastewater pollution by sharing with municipalities the costs of wastewater treatment facilities. The enabling legislation (P.L. 92–500) specifies that EPA's cost share will be 75% of construction costs. It further requires municipalities to collect user fees from industrial users of the facilities to repay that part of the federal grant allocable to the treatment of industrial wastewater. The municipality must return half of the user fees collected to the U.S. Treasury; the municipality is allowed to retain the remaining half. Retention by municipalities of these user fees lowers their effective cost shares and results in the following consequences: (1) a bias for municipalities to select certain kinds of abatement techniques regardless of whether or not they are the least-cost techniques from the national perspective; (2) a bias for municipalities to select larger-than-optimal scales of abatement facilities; (3) a hidden federal subsidy to industry; and (4) grants that favor industrial communities. This article examines the legislative and regulatory requirements for user charges, derives the algebraic expressions for calculating the real federal, municipal, and industrial cost shares with user fees; computes municipal cost shares for selected values of the determinant factors; evaluates efficiency and other consequences of current user fee arrangements; and concludes that the efficiency distortions brought about by the impacts of user fees on cost sharing could be eliminated by requiring that all user fees collected from industry against the federal cost share be returned to the U.S. Treasury. 相似文献
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Ronald F. Chamblee Marshall C. Evans Donna G. Patten June S. Pearce 《Journal of Safety Research》1983,14(1):21-35
This article provides national data on the types of injuries reported on death certificates, the external causes of these injuries, and diseases that are frequently reported with them. Injuries were a factor in 11 % (213,366 deaths) of the deaths to residents of the United States in 1978. Of 11 broad categories of injuries, three (fractures, sprains, strains, and dislocations, intracranial injuries, and adverse effects) were mentioned on almost 50,000 deaths each. There was considerable variation in the distribution of injury types by age, sex, and race. The most notable example was fractures of the lower limb which were mentioned on 29% of the deaths involving an injury to 65 + year olds but no less than 5% of such deaths for all other age groups. For white females, the percentage with a fracture of the lower limb was 23 % compared to 12 % overall. In 25 % of the deaths involving an injury, the immediate cause was a motor vehicle accident. In 51 %, the immediate cause of the injury was a non-motor-vehicle accident. In 73 % of the deaths involving non-motor-vehicle accidents, disease conditions as well as injuries were a factor; and, 69% of the time, the disease condition was actually the underlying cause of the death with the injury being a contributing factor or complication. For example, over 14,000 deaths in 1978 involved a circulatory condition as the underlying cause of death which was complicated by an accidental fracture, sprain, or dislocation. Although diseases more often assumed the role of the underlying cause of death, they were also a nonunderlying cause in 24,000 non-motor-vehicle accident deaths. Over 12,000 of such deaths involved circulatory diseases. 相似文献
37.
Marshall Gysi 《Journal of the American Water Resources Association》1975,11(3):551-558
ABSTRACT: The present energy and environmental crises are due to increasing per capita demands as well as increasing populations. The role that traditional pricing policies have played in promoting these demands is discussed. The reduction or stabilizing of per capita demands is advocated through the use of Conservational Pricing mechanisms which charge higher average prices for high consumption. An example of the effect of Conservational Pricing in the water supply industry is given. 相似文献
38.
Patrick Whitehead K.G. Willis Tim Marshall Susan Ball David Higdon 《Journal of Environmental Planning and Management》1988,31(1):61-64
The Garden City Utopia
Robert Beevers. The Macmillan Press, 1988. £27.50. 206 pages.
Cost‐Benefit Analysis in Urban and Regional Planning
J. A. Schofield. Allen and Unwin, London, 1987. 249 pages. £30 hardback.
The Milton Park Affair — Canada's largest citizen‐developer confrontation
Claire Helman. Véhicule Press, Montréal, 1987. $12.95.
Regenerating the Inner City, Glasgow's Experience
Edited by David Donnison and Alan Middleton. Routledge & Kegan Paul Ltd., London, 1987. £12.95.
Community Architecture
Nick Wates and Charles Knevitt. Penguin Books, London, 1987. £4.95. 相似文献
39.
Utilization of turkey manure as granular activated carbon: physical, chemical and adsorptive properties 总被引:1,自引:0,他引:1
The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water. 相似文献
40.
The dominant phytoplankton taxa during seasonal periods of peak primary productivity were identified during a 4 yr study (July 1989 to June 1993) in Chesapeake Bay. Maximum phytoplankton abundance occurred from late winter to early spring, and was dominated by a few species of centric diatoms. This development was followed by more diversified assemblages of diatoms and phytoflagellates that produced additional concentration peaks in summer and fall; all these maxima were accompanied by concurrent productivity peaks. High summer productivity resulted when the phytoplankton concentrations of diatoms and phytoflagellates were augmented by an increased abundance of autotrophic picoplankton. There was variability in both the seasonal and annual growth maxima of these algal populations and in total productivity. Higher cell concentrations and productivity were associated with higher nutrient levels on the western side of the bay, at sites adjacent to major tributaries. Periods of highest productivity were in spring and summer, ranging from 176 to 346 g Cm-2yr-1 over the 4 yr period, with a mean annual productivity of 255 g Cm-2yr-1. The bay stations rates ranged from 82 to 538 g Cm-2yr-1. 相似文献