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601.
602.
Behavioral Considerations in Fragmented Landscapes 总被引:1,自引:0,他引:1
603.
We develop a general model for pricing a depletable, replaceable asset, and discuss its application in determining optimal tipping fees for a sanitary landfill. We show that the optimal fee includes a component that grows at the real interest rate as space in the landfill is depleted, and then drops when a new landfill is built. Because the scarcity cost of landfill space increases as the landfill is filled, it may be optimal to delay a waste reduction program (such as recycling, composting, or incineration) until the landfill is partially full. 相似文献
604.
W. Graham Glen Michael P. Zelenka Richard C. Graham 《Atmospheric environment (Oxford, England : 1994)》1996,30(24):4225-4232
A model which quantifies the relationship between the monthly time series for CO emissions, the monthly time series in ambient CO concentration, and meteorologically driven dispersion was developed. Fifteen cities representing a wide range of geographical and climatic conditions were selected. An eight-year time series (1984–1991 inclusive) of monthly averaged data were examined in each city. A new method of handling missing ambient concentration values which is designed to calculate city-wide average concentrations that follow the trend seen at individual monitor sites is presented. This method is general and can be used in other applications involving missing data. The model uses emissions estimates along with two meteorological variables (wind speed and mixing height) to estimate monthly averages of ambient air pollution concentrations. The model is shown to have a wide range of applicability; it works equally well for a wide range of cities that have very different temporal CO distributions. The model is suited for assessing long-term trends in ambient air pollutants and can also be used for estimating seasonal variations in concentration, estimation of trends in emissions, and for filling in gaps in the ambient concentration record. 相似文献
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Richard R. Zavesky Alvin S. Goodman 《Journal of the American Water Resources Association》1988,24(6):1281-1287
ABSTRACT: This paper describes a new method of computing water-surface profiles, which does not require the assumption of hydrostatic pressure or of roughness coefficients. The method is based upon distributing entropy production values along a channel as uniformly as boundary conditions permit. The method requires a discharge capacity rating at a channel cross-section within the limits of the reach of the channel. A new theoretical relationship between the kinetic and momentum coefficients for the velocity profile is used, together with a dynamic programming technique for optimal distribution of energy losses along the channel. A computer model was developed and was used to verify the methodology for flood flow and channel data at four locations. 相似文献
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A study was conducted to quantitatively screen the Inner Harbor Navigation Canal of Lake Pontchartrain for the presence of EPA priority pollutants and any other pollutants detected in significant concentration. Water column samples were collected at different depths and on the flood and ebb tides. Compounds identified include aliphatic and aromatic hydrocarbons, phthlates, phenols, alcohols, amines, pesticides, herbicides, aldehydes, quinolines, fatty acids, carboxylic acids. These compounds were detected at the parts-per-trillion level. The concentrations of the individual organics detected on the flood and ebb tides were not significantly different. The data derived from samples taken at two different depths suggest that the distribution of organics in the water column was homogeneous. 相似文献
610.