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171.
OPTIMALITY OF RECYCLING AND THE LOCATION OF A RECYCLING CENTER 总被引:1,自引:0,他引:1
ABSTRACT. Consider a community investigating the integration of recycling into its waste management program. Even if (1) the county's citizens do not gain utility from recycling, (2) landfill space is plentiful, and (3) the market price for recyclables is zero, recycling can still be optimal for a local government. By determining the relationship between the amount of recycling and the location of a recycling center, conditions are identified under which recycling will reduce total waste management costs enough that municipal recycling will be optimal. In addition, it is shown that the likelihood of municipal recycling increases with the size of the city. 相似文献
172.
Robert E. Deyle 《政策研究杂志》1994,22(3):457-473
Innovation by "groping along," in which appointed public officials experiment during program implementation after little, if any, initial planning and analysis, has been promoted as a more accurate model of policy innovation than the rational comprehensive model of policy change. Analysis of two cases of environmental regulatory policy innovation suggests that administrative agencies may be more likely to follow the conventional model of the policy cycle when high levels of conflict are likely to accompany policy initiatives. The cases also suggest, however, that public officials will experiment during the innovation process when they are uncertain about the nature of the problem and the probable impacts of alternative solutions. 相似文献
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175.
The archaeological record of prehistoric Cyprus is rich, diverse, well-published, and frequently enigmatic. Regarded by many as a bridge between western Asia and the Aegean, Cyprus and its past are frequently seen from scholarly perspectives prevalent in one of those two cultural areas. Its material culture, however, differs radically from that of either area. Apart from the early colonization episodes on the island (perhaps three during the pre-Neolithic and Neolithic), evidence of foreign contact remains limited until the Bronze Age (post-2500 B. C.). This study seeks to present the prehistory of Cyprus from an indigenous perspective, and to examine a series of archaeological problems that foreground Cyprus within its eastern Mediterranean context. The study begins with an overview of time, place, and the nature of fieldwork on the island, continues with a presentation and discussion of several significant issues in Cypriot prehistory (e.g., insularity, colonization, subsistence, regionalism, interaction, social complexity, economic diversity), and concludes with a brief discussion of prospects for the archaeology of Cyprus up to and beyond 2000. 相似文献
176.
177.
Several samples of geological stones from statuary pedestals found in various archaeological sites in Cyprus have been characterized using non-contact laser infrared photothermal radiometry. Thermal diffusivities and effective optical absorption coefficients were calculated using a one-dimensional thermal-wave model. The mean values and standard deviations were tabulated and comparisons were made with lithographic and petrographic studies of the samples. Good correlations were found, thus demonstrating that laser photothermal archaeometry is a promising methodology for the accurate, potentially non-destructive and convenient characterization of the origins of ancient stones in Cyprus and other geological and archaeological sites. 相似文献
178.
Fifty-three copper-based metal fragments, recovered from the Robitaille site in southcentral Ontario, were analysed by neutron activation to establish their chemical make-up and to sort them by their trace elemental chemistries. Three different European copper samples, one brassy copper and 48 brass samples with five different chemistries were found. As few as eight trading actions may account for all of the recovered European metal fragments. 相似文献
179.
Robert Steffens 《Berichte zur Wissenschaftsgeschichte》1995,18(4):259-260
180.