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991.
Donald E. Agthe R. Bruce Billings Judith M. Dworkin 《Journal of the American Water Resources Association》1988,24(3):627-630
ABSTRACT: Socioeconomic determinants of individual household water use were estimated using regressions of these characteristics with actual household water use for winter and summer. Results were disaggregated between those consumers who were aware of an increasing block rate price structure and those who were not. Most of the informed group members believed that this price structure did result in significant reductions in water use. Nevertheless, overall water use was greater for the informed group. The determinants of water use were found to differ between informed and uninformed users as well as between winter and summer. The uninformed users were influenced by a larger set of variables in each season than the informed group. In winter, the informed group members with swimming pools and/or arid landscaping used less water than their uninformed counterparts. Summer water use increased with length of tenancy in home for the uninformed group but not for informed, while increasing with ownership for informed consumers. 相似文献
992.
A pedestrian safety education film titled And Keep on Looking and aimed at children ages 9 to 12 was evaluated in several cities. The results showed an increase in safe street crossing knowledge among 9- to 12-year-old Connecticut children who viewed the film, and some improvement in safe street crossing behavior among 9- to 12-year-old Seattle, Washington, children. Crash reduction was assessed in a 2-year, citywide field test conducted in Milwaukee. The field test indicated a crash reduction of more than 20% for 9- to 12-year-old children in Milwaukee compared with children in areas surrounding Milwaukee and children in comparison cities. 相似文献
993.
994.
Lois E. Tetrick 《组织行为杂志》1995,16(6):583-595
This article presents a dynamic model of the process in which union commitment is developed and maintained. Central to the model is the fact that commitment occurs in a context of organizational rights which are provided by the union as well as organizational responsibilities or citizenship behaviors on the part of union members. Based on an integration of the literature on organizational citizenship behaviors, psychological contracts, and organizational socialization, specific hypotheses are proposed. 相似文献
995.
Efficient, economical treatment of mercury-contaminated soils and industrial wastes requires a treatment process that reduces mercury content to near background levels (<1 ppm) and recovers the removed mercury in pure recyclable form without producing liquid, solid, or gaseous secondary wastes. This article reviews the results achieved using a medium-temperature thermal desorption process developed and commercialized by Mercury Recovery Services, Inc. (MRS) that has successfully achieved these goals. 相似文献
996.
William E. Fristad 《补救:环境净化治理成本、技术与工艺杂志》1995,5(4):61-72
COGNIS TERRAMET® soil leaching and Bescorp soil washing systems have been successfully combined to remediate an ammunition test burn area at the Twin Cities Army Ammunition Plant (TCAAP), New Brighton, Minnesota. This cleanup is the first in the country to successfully combine these two technologies, and it offers a permanent solution to heavy metal remediation. Over 20,000 tons of soil were treated in the project. The cleaned soil remained on-site, and the heavy metal contaminants were removed, recovered, and recycled. Eight heavy metals were removed from the contaminated soil achieving the very stringent cleanup criteria of <175 ppm for residual lead and achieving background concentrations for seven other project metals (antimony, cadmium, chromium, copper, mercury, nickel, and silver). Initial contaminant levels were measured as high as 86,000 ppm lead and 100,000 ppm copper, with average concentrations over 1,600 ppm each. In addition, both live and spent ordnance were removed in the soil treatment plant to meet the cleanup criteria. By combining soil washing and leaching, COGNIS and Bescorp were able to assemble a process which effectively treats all the soil fractions so that all soil material can be returned on-site, no wastewater is generated, and the heavy metals are recovered and recycled. No hazardous waste requiring landfill disposal was generated during the entire remedial operation. 相似文献
997.
The spatial coincidence between riparian buffers of various widths and extents and potentially unstable ground was quantified
using a physically based model for shallow landslide initiation and GIS for two watersheds on the Olympic Peninsula, Washington,
USA. The proportion of the potentially unstable ground in each watershed within riparian buffers is a function of both buffer
width and the extent of the stream channel network being buffered. While current buffers required by Washington State cover
less than 5% of the potentially unstable ground, buffering all stream channels in these watersheds with 100-m buffers covered
75%–90% of the potentially unstable areas. Our analyses further show that: (1) riparian buffers are not efficient mechanisms
for protecting potentially unstable ground, and (2) identifying potentially unstable ground using a physically based model
should prove more effective for designing methods to reduce shallow landsliding hazards than relying on extensive buffer zones
along stream channels. 相似文献
998.
A. David Kline 《Journal of Agricultural and Environmental Ethics》1995,8(2):190-197
The focus of the paper is the ethical issues associated with the practice of dissecting animals in lower level college biology classes. Several arguments against dissection are explored. Furthermore, the issue is examined from the point of view of the instructor's academic freedom and the point of view of a student's moral autonomy. It is argued that even though the arguments against dissection fail, it is very important to respect the moral autonomy of students who oppose the practice. Often this can be accomplished in a manner that is consistent with academic freedom and good science education. 相似文献
999.
A hierarchical approach to fisheries planning and modeling in the Columbia River Basin 总被引:1,自引:0,他引:1
The Columbia River Basin is the scene of a massive effort to restore populations of Pacific salmon (Oncorhynchus spp.) and steelhead (O. mykiss). Efficient restoration is confounded by a high level of complexity, competing sociopolitical goals and values, and uncertainty
about key system properties. Simulation models and other tools of systems analysis are important to development of a comprehensive,
regionally acceptable strategy. Hierarchy theory provides a useful paradigm for organized complexity within the Columbia Basin
and the basis for a trilevel hierarchical structure for organizing and integrating models. Life-stage models compose the most
basic simulation units at the lowest level in the proposed hierarchical modeling structure. Each life-stage model simulates
a distinct period in the life cycle of anadromous salmonids. Population models at the intermediate level simulate the complete
life cycles of salmon and steelhead populations. At the highest level in the hierarchy, interpopulation models simulate extensive,
long-term processes that affect multiple species and stocks. A hierarchical system of models is preferable to a single model
or to a group of models lacking formal structure. A principal advantage is that models have the correct spatial and temporal
resolution for analyzing questions at different scales. A hierarchical structure also facilitates the flow of information
among models, and aids in understanding the impacts of uncertainty. Constructing a hierarchy of models should involve both
bottom-up and top-down perspectives that maintain logical consistency among models, while allowing unique model structures
appropriate for each level in the hierarchy. 相似文献
1000.
Some studies have been done dealing with cattle manure treatment, but literature scarcely reports the use of immobilized microalgae as final treatment of this waste. Recently, a complete technology for cattle manure treatment was established, including immobilized microalgae. The influence of the recirculation in the efficiency of the immobilized microalgae process was evaluated. 相似文献