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111.
The Norwegian MEPS (musculoskeletal--visual--psychosocial--stress) study included 3 groups: data entry, data dialogue (female) and data dialogue (male). Before intervention, the data entry group reported significantly more symptoms and signs of musculoskeletal illness and had longer periods in front of the video display terminal (VDT) without a break. The ergonomic intervention consisted mainly of ergonomic information and training. After intervention, the data dialogue female group reported a significant reduction in shoulder pain in parallel with a reduction in trapezius load. Increasing the understanding in how to adjust the work stand and chair may have been contributing factors to reducing the pain level. There was a significant reduction in eye problems in all groups; the greatest reduction in eye symptoms was seen in the groups who had new optometric corrections.  相似文献   
112.
The Groundwater Protection Project at the US Department of Energy Hanford Site in Washington State is currently developing the means to assess the cumulative impact to human and ecological health and the regional economy and cultures from radioactive and chemical waste that will remain at the Hanford Site after the site closes. This integrated system is known as the System Assessment Capability (SAC). The SAC Risk/Impact Module discussed in the article uses media- and time-specific concentrations of contaminants estimated by the transport models of the integrated system to project potential impacts on the ecology of the Columbia River corridor, the health of persons who might live in or use the corridor or the upland Hanford environment, the local economy, and cultural resources. Preliminary Monte Carlo realizations from the SAC modeling system demonstrate the feasibility of large-scale uncertainty analysis of the complex relationships in the environmental transport of contaminants on the one hand and ecological, human, cultural, and economic risk on the other. Initial impact results show very small long-term risks for the 10 radionuclides and chemicals evaluated. The analysis also helps determine science priorities to reduce uncertainty and suggests what actions matter to reduce risks.  相似文献   
113.
The educational and research roles of universities in environmentally conscious technologies are discussed from a historical perspective. The American university system, and in particular its interactions with government and industry, is compared with that of the United States' main trading partners including Japan, the NAFTA countries, and Western Europe. Examples of federally funded U.S. programs related to green design are also tabulated. The role of universities within the framework of society, politics, and economics is discussed in regard to emerging concepts such as sustainable development, life-cycle analysis, and design for environment, as well as the functioning of local recycling infrastructures. The means by which universities can contribute to environmentally conscious technology are summarized, as are the demands placed on the next generation of engineers.  相似文献   
114.
ABSTRACT: Gaging stations established in 1895 at Millville, West Virginia and in 1882 at Harpers Ferry, West Virginia record flows ranging from a maximum of 6,509 m3s-1 to a minimum of 2 m3s-1. Historical and botanical indicators were used to extend the systematic flood record of the Shenandoah River for a study reach approximately 7.5-km long. The long systematic record at the site provides a good opportunity to assess the accuracy of these sources of paleoflood information. Habitation of the area by settlers of European descent began in 1733, and historical flood records extend from 1748. Qualitative historical records from different sources were compared to yield the most complete flood history. The correlation between the various sources was extremely high. Botanical flood evidence preserved as adventitious sprouts, tree scars, and ring anomalies were documented in 37 trees. A flood chronology established from these data extended from 1896 to 1955. Botanical indicators provided an accurate, although incomplete, flood chronology. The ability to determine accurate flood stages from paleohydrologic indicators varied. Historical data yielded relatively accurate stages to within 1–2 m; only minimum values of flood stage could be obtained from botanical indicators. These results illustrate some of the strengths and weaknesses of paleohydrologic investigations in the eastern United States.  相似文献   
115.
Lawrence Livermore National Laboratory (LLNL), one of the nation's three national security laboratories, is initiating a major research effort in industrial ecology with the goal of increasing the economic and environmental efficiency of the U.S. and global economies. Closer to home, ongoing efforts to reduce LLNL's environmental impact on the surrounding community provide an example of how the environmental efficiency of a major research facility can be systematically improved. In the late 1980s, LLNL initiated its waste minimization and pollution prevention program, changing its focus from end-of-pipe waste management to a proactive and preventive strategy—total quality environmental management (TQEM). LLNL's success in integrating pollution prevention with R&D and operational activities is well illustrated by the waste reduction and energy and water conservation accomplishments described in this article. LLNL represents a model of how industrial ecology, design for environment, and pollution prevention can be incorporated into a comprehensive R&D and operational program. This article describes LLNL's developing industrial ecology program, gives some specific technical accomplishments that have application to many industrial facilities, and presents a case study of TQEM at LLNL's remote experimental test facility, Site 300. The integration of TQEM philosophy with LLNL's scientific capabilities holds much promise for new ideas and creative solutions to national and international industrial ecology concerns.  相似文献   
116.
For over a century, western economic development has depended upon the use of combustible hydrocarbons for its energy needs. The 20th century saw the prolific exploitation of fossil hydrocarbon sources (coal and oil) which are finite and exhaustible. There is a clear need for society to conserve such non-renewable resources. In addition to conservation, a wholesale switch to renewable energy sources should be seen as the first research and development priority. In the interim, moving towards a crop-based fuel economy appears to be a good alternative to provide the necessarily dramatic changes in lifestyle and mindset that would be required of consumers, for a wholesale shift away from hydrocarbon combustion. Before programs and policies designed to address the need for an interim or alternative energy and materials economy are put into place however, it is important to understand the barriers and opportunities put forth by society itself. Conventional frameworks designed to understand this type of change are of limited assistance. This paper argues that institutional thinking is a very useful tool in addressing these types of environmental problems.  相似文献   
117.
ABSTRACT: Maintenance of the more than 24 million septic tanks in the U.S. requires removal and disposal of septage. Disposal options include application to agricultural lands where the nutrients and organic matter can provide soil benefits. However, pathogens and contaminants are also contained in septage. An extensive search turned up very few data on septage quality, and those reveal high variability. The data used by the U.S. Environmental Protection Agency (EPA) in developing regulations had the lowest metal concentrations among the nine data sets that could be compared. Based on these data, EPA assumed that septage could be applied to agricultural land for more than 100 applications before reaching unacceptable cumulative loading of metals. They thus did not establish federal standards for metals in septage, and no monitoring is required under federal rules governing septage disposal. Analysis of the nine data sets we found showed that field site life would be reached in less than 100 applications for most septage and cumulative loading limits established by EPA for sewage sludges will be exceeded in 16 applications for some septage as opposed to the 100 application estimate used by EPA. Determination of acceptable cumulative loading depends on numerous technical and policy considerations. All septage sources reached the more restrictive loading limits such as those established by the New York State Department of Environmental Conservation (NYSDEC) and the recommendations in Cornell publications in less than 100 applications. In one case the cumulative limit for copper was exceeded in a single application. These findings suggest additional data are needed on septage quality and that the federal and state agencies responsible for regulating application of septage to agricultural land should reassess their standards.  相似文献   
118.
ABSTRACT: A regression analysis using a generalized least squares approach on flow data from the driftless area of Wisconsin indicates that the ratio of drainage area to time-to-peak is a good predictor of flood quantiles. The estimation of time-to-peak (or some other measure of basin response time) requires direct measurement of river stage and possibly rainfall at the site of which the quantiles are to be estimated. The cost-effectiveness of such an approach must yet be determined.  相似文献   
119.
Abstract: Rapidly growing regions such as the western United States face difficult challenges in mobilizing new water supplies to meet new demands. Environmental concerns have curtailed the scope for large new surface storage projects, and widespread basin overdraft has limited ground water’s potential as a source of expansion. Drawing on the California experience, this article explores modern water planning approaches, which focus on a portfolio of options including nontraditional sources (recycling, desalination, underground storage) and more efficient use of existing supplies (conservation and water marketing). It reviews the advantages and drawbacks of the elements of the portfolio, provides examples of innovative planning approaches, and assesses the role for supportive government policies.  相似文献   
120.
In August of 2003 a severe wildfire burnt the majority of Fishtrap Creek, a 170 km2 catchment in central British Columbia, Canada. The objective of this study was to determine the short-term (15-month) influence of the wildfire on the amount and composition of fine sediment delivery and retention in the system and to compare it to a similar unburnt catchment. In the spring of 2004 automatic water samplers were installed at a gauging site on Fishtrap Creek to collect suspended sediments from the snowmelt runoff and gravel traps were deployed on the channel bed surface to collect composite samples of suspended fine sediment. Jamieson, the reference creek, exhibits similar geology and pre-burn vegetation and was sampled in the same manner for comparison. Composite suspended sediment collected in the traps was removed from the streams in mid-summer and early September. Quantitative estimates of the amount and particle size structure of the naturally stored fine sediment in, and on, the gravel creekbed were obtained in pre-melt, mid and late-summer conditions. Estimates of suspended sediment yields indicated that while the burnt system delivered 66% more material per unit area, the total seasonal suspended sediment yield was low (855 kg km−2) compared to other fire-disturbed systems. While the burnt catchment was primed to deliver sediment, the hydrologic drivers were not of sufficient magnitude to generate a substantial response, suggesting that in this first post-fire year the system was transport-limited, not supply-limited. Differences were noted in the spatial and seasonal composition of the <500 more OM% composite suspended sedimentswith the burnt catchment having significantly (P≤0.05) more OM%. Seasonally a significant increase of OM% in late summer samples was associated with instream biofilms and possible delivery of black carbon. The system’s post-fire response was not geomorphically substantial but significant biological differences were noted in the short-term.  相似文献   
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