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191.
William M. Cox Jon Clark 《Journal of the Air & Waste Management Association (1995)》2013,63(7):762-766
Data on dally maximum ozone concentrations measured at ambient air monitoring stations operated by state and local air pollution control agencies in the Eastern United States were analyzed using principal factor analysis. Four orthogonal factors representing O3 formation potentials were derived using the statistical package SPSS; these factors accounted for over two-thirds of the variations in 1978 summer O3 levels at 21 urban-oriented stations. The analysis confirmed that O3 variations are similar among stations within defined geographical areas; this confirmation supports the widely held theory that ambient O3 formations are reglonwlde. The analysis suggested that trends analysis for determining general progress in improving O3 air quality should be based on aggregate statistics from clusters of monitors rather than from a single monitoring station within areas associated with the derived factors. 相似文献
192.
As a consequence of the U.S. effort to increase infrastructure security and resilience, the Department of Homeland Security (DHS) and other U.S. federal agencies have identified 16 critical infrastructure sectors that are considered vital to the nation’s well-being in terms of economic security, public health, and safety. However, there remains no articulated set of values that justify this particular list of infrastructure systems or how decision-makers might prioritize investments towards one critical sector over another during a crisis. To offer a more integrated and holistic approach to critical infrastructure resilience, this research employs the capabilities approach to human development, which offers an alternative view of critical infrastructure that focuses on the services that infrastructure provides rather than its physical condition or vulnerability to threats. This service-based perspective of infrastructure emphasizes the role of infrastructure in enabling and supporting central human capabilities that build adaptive capacity and improve human well-being. We argue that the most critical infrastructure systems are those that are essential for providing and/or supporting central human capabilities. This paper examines the DHS designation of criticality from a capabilities perspective and argues for a capabilities basis for making distinctions between those systems that should be considered most critical and those that might be temporarily sacrificed. A key implication of this work is that an across sector approach is required to reorganize existing critical infrastructure efforts around the most valuable infrastructure end-services. 相似文献
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Tanh T. N. Nguyen Kati W. Migliaccio Edward A. Evans Christopher J. Martinez John J. Sansalone Mark W. Clark 《Journal of Environmental Planning and Management》2017,60(5):842-861
We developed a comprehensive coupling framework with a multi-objective optimization that bridges a water balance model (WBM) and a wetland service model (WSM) to supporting wetland management. The framework was tested for management in Tram Chim National Park (with four wetland zones) where hydro-economic optimization was needed. The framework used (1) a model coupling process bridging WBM and WSM to create a modular hydro-economic model (MHEM), (2) a multi-objective optimization, and (3) an anneal scheduling for scenario optimization. The framework demonstrated its competency in identifying cause–effect/interaction flows (bridges) between WBM and WSM to design MHEM to simulate optimized scenarios; for the case study, the multi-objective optimization was met for all wetland zones. Results suggested a flexible consideration of management scales for optimization, i.e. hydrologic optimization at a zone level and net benefit optimization at a Park level. Our framework is applicable to supporting complex wetland decisions considering multiple objectives. 相似文献
195.
Stephanie A. Freeman Ross Dugas David H. Van Wagener Thu Nguyen Gary T. Rochelle 《International Journal of Greenhouse Gas Control》2010,4(2):119-124
Concentrated, aqueous piperazine (PZ) has been investigated as a novel amine solvent for carbon dioxide (CO2) absorption. The CO2 absorption rate of aqueous PZ is more than double that of 7 m MEA and the amine volatility at 40 °C ranges from 11 to 21 ppm. Thermal degradation is negligible in concentrated, aqueous PZ up to a temperature of 150 °C, a significant advantage over MEA systems. Oxidation of concentrated, aqueous PZ is appreciable in the presence of copper (4 mM), but negligible in the presence of chromium (0.6 mM), nickel (0.25 mM), iron (0.25 mM), and vanadium (0.1 mM). Initial system modeling suggests that 8 m PZ will use 10–20% less energy than 7 m MEA. The fast mass transfer and low degradation rates suggest that concentrated, aqueous PZ has the potential to be a preferred solvent for CO2 capture. 相似文献
196.
Fetal loss through miscarriage or termination of pregnancy for genetic reasons often provokes the grief of bereavement. This is not fully understood, and the extent of the distress is often underestimated by professionals and family alike. We have examined elements of the normal bereavement process and have found that they may occur in specific and accentuated forms in mid-trimester fetal loss. We discuss our findings in the light of the attachment theory—a psychodynamic model for understanding grief reactions. 相似文献
197.
Assessing the Vulnerability of Coastal Communities to Extreme Storms: The Case of Revere,MA., USA 总被引:6,自引:1,他引:6
Clark George E. Moser Susanne C. Ratick Samuel J. Dow Kirstin Meyer William B. Emani Srinivas Jin Weigen Kasperson Jeanne X. Kasperson Roger E. Schwarz Harry E. 《Mitigation and Adaptation Strategies for Global Change》1998,3(1):59-82
Climate change may affect the frequency, intensity, and geographic distribution of severe coastal storms. Concurrent sea-level
rise would raise the baseline of flooding during such events. Meanwhile, social vulnerability factors such as poverty and
disability hinder the ability to cope with storms and storm damage. While physical changes are likely to remain scientifically
uncertain into the foreseeable future, the ability to mitigate potential impacts from coastal flooding may be fostered by
better understanding the interplay of social and physical factors that produce human vulnerability. This study does so by
integrating the classic causal model of hazards with social, environmental, and spatial dynamics that lead to the differential
ability of people to cope with hazards. It uses Census data, factor analysis, data envelopment analysis, and floodplain maps
to understand the compound social and physical vulnerability of coastal residents in the city of Revere, MA, USA.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
198.
John E. Elliott Megan L. Harris Laurie K. Wilson Philip E. Whitehead Ross J. Norstrom 《Ambio-人类环境杂志》2001,30(7):416-428
从1983~1998年,沿加拿大不列颠哥伦比亚海岸,我们监测了21处大蓝鹭(Ardea herodias)结巢处卵内多氯二苯并-p-二恶英 (PCDDs)、二苯并呋喃(PCDFs) 和多氯联苯 (PCBs)的污染情况。20世纪90年代早期,主要的同类物如1,2,3,7,8-PnCDD、 1,2,3,6,7,8-HxCDD、2,3,7,8-TCDD、2,3,7,8-TCDF、1,2,3,7,8,9-HxCDD 和2,3,4,7,8-PnCDF在纸浆厂分子氯漂白技术被新的漂白技术替代以及氯基酚类木材保存剂和抗木材变色剂的使用被严格地限制之后有显著下降。被捕食的鱼与大蓝鹭卵内污染物水平之间的强正线性回归说明,每天在本地摄食的食物是大蓝鹭暴露于污染物的一个重要路径。从1985年到1991年,在某些栖居地的大蓝鹭卵内所测到的毒当量浓度(TEQs)足以在小鹭体内产生胚胎毒性。尽管PCDD/Fs有所减少,但估计整个80年代有些城市中苍鹭栖居地的毒当量浓度由于多氯联苯的作用而居高不下。 相似文献
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