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631.
After the Great East Japan Earthquake in March 2011, numerous evacuees had to stay in evacuation shelters such as school gymnasiums. In general, after a disaster, ensuring the safety and security of evacuees in evacuation shelters is a serious problem. Consequently, many of these evacuees feared that they would be victims of crime in the shelters or that their evacuated homes would be burgled. To examine what factors evoke a general fear of crime in shelters and burglary of evacuated homes, we conducted an online questionnaire on 300 evacuees in Miyagi Prefecture who had stayed at such shelters. From a factor analysis of fear of 16 specific kinds of crime in shelters, we extracted two factors representing fear of property and female-related crime. We then found that a general fear of crime in shelters was associated with being young and a fear of female-related crime, while a fear of burglary of evacuated homes was associated with being female, owning a detached house, and fear of property crime. Based on these results, we provide recommendations aiming to help reduce the fear of crime in shelters and burglary of evacuated homes. 相似文献
632.
Richard E Plant Marc Mangel Lawrence E Flynn 《Journal of Environmental Economics and Management》1985,12(1):45-61
The problem of selecting a pesticide application strategy in the face of increasing resistance to the pesticide in the pest population is dealt with. The grower in this situation may do better by sacrificing a portion of the present crop in return for a reduced resistance to future applications. The model presented represents an attempt to forge a compromise between excessive complexity, rendering the model difficult to study, and excessive simplicity, rendering the model useless. The effects of timing of the application of the pesticide within the season are discussed. The principle conclusions are the following: (i) If immigration of pests from refugia is significant then proper timing of the application of pesticide may be used to help alleviate resistance growth. (ii) Resistance growth may best be reduced by spraying earlier than what would otherwise be the best time. (iii) The value of the discount rate (and of the time horizon) has a profound effect on the nature of the optimal policy. 相似文献
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636.
Behavioral Considerations in Fragmented Landscapes 总被引:1,自引:0,他引:1
637.
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
638.
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
639.
640.
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