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121.
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123.
The semiconductor industry plays a leading role in supporting economic stabilization and social progress in Taiwan. In this paper, Eco-indicator 95 and Impact 2002+ are utilized to evaluate the potential environmental impacts from five production processes of the double data rate synchronous dynamic random access memory (DDR SDRAM). The comparisons between these two impact methods and their scopes are also discussed.From our results, global warming potential and non-renewable energy consumption were identified as the major environmental impacts. Applications of Eco-indicator 95 and IMPACT 2002+ also suggest that summer smog and respiratory inorganics are significant impact categories. The comparison of the scopes of these two methods identifies that low GWP potential PFCs substitution and electricity saving are effective ways to decrease environmental impacts of DRAM manufacturing. In addition, IMPACT 2002+ is a more applicable LCA method for the semiconductor industry in Taiwan due to the structure and reference area of this method and the characteristics of the semiconductor industry in Taiwan. 相似文献
124.
James Lewis 《The Environmentalist》1982,2(3):233-246
Summary The mitigation of natural disasters essentially depends upon the identification and adjustment of human ecological processes
contributing to conditions of vulnerability. The analysis of vulnerability requires the local study of political, social,
and economic processes which have contributed, and are contributing, to a vulnerable condition in a hazardous environment.
One of the few similarities between Tonga and Algeria is a continuing experience of natural disaster after independence from
previous colonial administrations. In two very different but complementary projects, ways are identified for the adjustment
of assumed or inherited priorities for development, to take practical account of continuing hazards. The high vulnerability
of rural areas is a factor common to both countries, as well as to many others. The analysis of conditions and systems in
two dissimilar countries may have begun a process of implementation, one which must necessarily follow theoretical analysis
for the realisation of practical value. The degree and nature of disaster impact is conditioned as much by normally prevailing
conditions and systems as by the manifestation of natural hazard. Direct experience of hazardous environments, and of problems
caused by disaster, must be made to result in the creation of multi-disciplinary environmental policies for disaster mitigation,
inclusive of small scale development and education and training programmes for continued implementation. Comprehensive and
simultaneous strategies for disaster avoidance, disaster resistance, and disaster accomodation must be made integral components
of local development planning. 相似文献
125.
James Lewis 《The Environmentalist》1983,3(4):277-287
Summary The occurrence of disastrous manifestations of hazard are not usually unique events. In analysis of the causes and effects
of these occurrences there are problems for analysts, academics and policy-makers in the understanding of long-term perspectives
as the context for recent events and future policies. Understanding will be made initially, but necessarily, more complex
by the variety of standpoints of different interest groups in the affected community, and of the community at large.
Physical permanence of a community cannot beassumed in a changing environmental condition. Vulnerability to the sea has increased during the thousand years of Chiswell's existence,
and is continuing to do so. Understanding of this changing state by various groups in society, and their administrators, is
the key to the selection and effectiveness of interacting social and technological measures whether undertaken specifically
against hazard or not.
The extent to which technology can be effectively mobilised and implemented to ensure prolonged community permanence may only
be assessed by detailed analysis of environmental phenomena on the one hand, and by comparison with social adjustments on
the other. Social adjustments cannot be compared until those options are made realistically available by the authorities elected
for their administration.
The condition of vulnerability is not static. Analysis and assessment of short- and longer-term issues is at once a multi-disciplinary
process calling for a fusion of physical and earth sciences, social sciences, and political and administrative processes.
That these sciences and processes are themselves evolving, and are not static, is as true as for vulnerability itself. That
all are in short- and long-term processes of change must be understood if each is to be integrated with the other for maximum
comprehensive and effective response to natural hazard. 相似文献
126.
Lewis A. Rossman Frank T. Vanecek 《Journal of the American Water Resources Association》1978,14(4):842-855
ABSTRACT: An improved computational procedure for solving water quality management models containing interacting pollutants and control policies is presented. The method is developed with respect to the specific problem of minimizing the costs of basin-wide thermal and organic pollution control to meet water quality standards. It views the problem in partitioned form where a master problem is used to find cooling levels for thermal polluters while subproblems determine optimal organic pollutant reductions for fixed cooling levels. A gradient based search procedure is used to solve the master problem. Computational results for several river systems are presented. Application of the method to other water quality management models is suggested. 相似文献
127.
Doug C. Nelson P. Thomas Cox 《Journal of the American Water Resources Association》1979,15(3):706-717
ABSTRACT: Decision parameters affecting combined use of effluent discharges and surface flows and ground water available at Gillespie Dam on the Gila River in Arizona are identified and analyzed. Hydrologic, economic, legal, and institutional parameters are considered separately and in combination. The interrelationships of irrigation subsystems, water use functions, institutional involvement, economic and legal constraints are illustrated. Recent hydrologic studies indicate that the natural flow of the Gila River will increase with the discharge of Phoenix sewage effluent and then there will be a drastic decline when the Palo Verde Nuclear Generating Station commences in 1985. Competition for any increases in effluent discharges and surface flows could be ameliorated through the combined efforts of existing or reorganized entities resulting in sharing of costs and benefits. The analysis leads to recommendations concerning joint use of facilities, proration of fixed and variable costs, and creation of a mutual water company. 相似文献
128.
Long-term application of poultry (Gallus gallus domesticus) litter has built high levels of P in certain Coastal Plain soils of north Louisiana. However, soil P/runoff P relationships for soil and environmental conditions of the area have not been examined. This study measured soil P (total, Bray 1, Bray 2, Mehlich 3, resin-exchangeable, and water-extractable) and runoff P (dissolved P, DP; and total P, TP) at four pasture sites previously amended with poultry litter. Sites varied in soil P due to annual litter applications ranging from 1 to more than 20. Three replicated plots at each site were subjected to simulated rainfalls over 2 yr, and concentrations of DP and TP in runoff were measured and related to soil P. This allowed examination of soil P/runoff P relationships and their changes over time. Runoff DP was also related to DP desorbed from surface soil in a miscible displacement experiment. Among measures of soil P, only resin-exchangeable and water-extractable P showed significant decreases over 2 yr. These measures of soil P explained 54 to 64% of the variability in runoff DP data. However, the miscible displacement technique proved the best indicator of runoff DP, explaining 70% of the variability. Runoff varied among sites (decreasing with increasing years of litter application), limiting the predictive capability of the soil extraction methods. Linking runoff characteristics with miscible displacement data may be a useful predictive tool and warrants further examination. 相似文献
129.
Changing places, changing emissions: The cross-scale reliability of greenhouse gas emission inventories in the US 总被引:1,自引:0,他引:1
William E. Easterling Colin Polsky Doug Goodin Michael W. Mayfield William A. Muraco Brent Yarnal 《Local Environment》1998,3(3):247-262
Greenhouse gas (GHG) emission inventories, which currently inform abatement policy discussions, are developed mostly from national scale data. Nevertheless, although the policy debate tends to take place in global and national arenas, action to abate GHG emissions is inherently within the provenance of local institutions and communities. The purpose of this paper is to examine how much information is lost by not estimating GHG emissions data at scales finer than the whole US. Such information may be critical in bridging global and local policy. Differences in the composition of GHG emission sources based on GHG emission inventories at three nested spatial scales (national, state, local) for four study sites (in Kansas, North Carolina, Ohio and Pennsylvania) are analysed, drawing upon initial results of a large collaborative study known as the 'Association of American Geographers-Global Change in Local Places (GCLP)' project. The concept of spatial sovereignty of emissions is developed to test the cross-scale reliability of emission inventories. For the test year 1990, close agreement is found in the by-gas composition of GHG emissions among national, state and local inventories. Spatial sovereignty in this case is maintained. However close agreement is not found in the by-source composition of GHG emissions among national, state and local inventories. Spatial sovereignty in this case is not maintained. Regular compilation of state and local emissions source inventories may be necessary to track important spatial and temporal deviations from national trends. 相似文献
130.
Geophysical and Hydrologic Monitoring of Air Sparging Flow Behavior: Comparison of Two Extreme Sites
The distribution of air around injection wells is an important determinant of the effectiveness, design, and cost of air sparging remediation systems. High-level air sparging field tests were conducted at two sites for the purpose of determining the pattern of airflow under widely different subsurface conditions. One site consisted of relatively homogeneous dune sand (Site A). The other consisted of highly heterogeneous glacial till (Site B). At both sites, cross-borehole electrical resistance tomography (ERT) was used to image the principal region of airflow in the saturated zone. The response of conventional monitoring data was compared with the ERT results. At Site A, the principal region of airflow was approximately symmetric about the sparge well and only 2.4 m in radius. At Site B, the pattern of airflow was much more complex and had a major horizontal component. In both site studies, conventional monitoring data provided a much more ambiguous indication of the region of airflow in the saturated zone than did ERT. The investigations at these two sites demonstrate that, while the exact distribution of injected air is not readily discernible by conventional monitoring, the character of the airflow pattern can be recognized when appropriate physical response data are collected. Such response data can be used to evaluate site suitability for air sparging and to improve the system design and operation. 相似文献