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161.
Tsai, Yushiou, Sara Cohen, and Richard M. Vogel, 2011. The Impacts of Water Conservation Strategies on Water Use: Four Case Studies. Journal of the American Water Resources Association (JAWRA) 47(4):687‐701. DOI: 10.1111/j.1752‐1688.2011.00534.x Abstract: We assessed impacts on water use achieved by implementation of controlled experiments relating to four water conservation strategies in four towns within the Ipswich watershed in Massachusetts. The strategies included (1) installation of weather‐sensitive irrigation controller switches (WSICS) in residences and municipal athletic fields; (2) installation of rainwater harvesting systems in residences; (3) two outreach programs: (a) free home indoor water use audits and water fixture retrofit kits and (b) rebates for low‐water‐demand toilets and washing machines; and (4) soil amendments to improve soil moisture retention at a municipal athletic field. The goals of this study are to summarize the effectiveness of the four water conservation strategies and to introduce nonparametric statistical methods for evaluating the effectiveness of these conservation strategies in reducing water use. It was found that (1) the municipal WSICS significantly reduced water use; (2) residences with high irrigation demand were more likely than low water users to experience a substantial demand decrease when equipped with the WSICS; (3) rainwater harvesting provided substantial rainwater use, but these volumes were small relative to total domestic water use and relative to the natural fluctuations in domestic water use; (4) both the audits/retrofit and rebate programs resulted in significant water savings; and (5) a modeling approach showed potential water savings from soil amendments in ball fields.  相似文献   
162.
从驾驶员生理、心理特性角度,阐述了沙漠地区道路交通安全的各影响因素,分析了长距离公路驾驶员出现疲劳现象时的生理、心理特性变化,运用灰色关联度分析得到驾驶员生理、心理特性--行车时间衰退曲线,结合目标公路附属设施设置实际情况情况,提出了更具有针对性的强制休息处运用体系.最后以阿拉尔-和田沙漠公路安全畅通工程建设为实例,详细阐述强制休息处运用体系研究情况.  相似文献   
163.
This paper examines the ways residents in the Grampians area in the Australian state of Victoria used their local and their state and national based media before, during and after the 2006 bushfires (wildfires). The researchers were particularly concerned to understand how residents evaluated media sources as trustworthy and credible in relation to bushfire warnings and information about the fires delivered in the media.

Analysis of data derived from two separate focus group sessions conducted by the researchers reveals four main themes. (1) The media are perceived as part of a broader information gathering process. (2) Local knowledge is the most important aspect in broadcast information. (3) Members of small communities can feel disenfranchised and resentful of the media when media coverage focuses on larger towns, and (4) the effects of media reporting, including specific warnings, are both immediate and long lasting.

The paper explores some of the tensions that result from the ways rural residents use and distinguish between local/regional and metropolitan and out-of-state bushfire information; and it encourages better use of the local/regional media to increase community safety and awareness in relation to bushfire mitigation, preparedness and crisis management issues before, during and after the fires. It is suggested that risk communications professionals need to understand that when mediated risk-related communications are provided, a key evaluative criterion is whether or not those media and the messages represent and reflect local knowledge.  相似文献   
164.
This paper readdresses the person–situation debate in organizational research. The well‐known arguments of Davis‐Blake and Pfeffer (1989) are evaluated in light of research and theory that has transpired since the publication of their original critique. A new dispositional model of job satisfaction is then proposed. The model is based on several informational and action steps including exposure to work events and condition, as well as the evaluation, memory, retrieval, and expression of affect in the organizational context. Using this model, we discuss how dispositional affect can influence what is experienced in the workplace, how one evaluates it, and how it is expressed to others, including organizational researchers. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
165.
There is an urgent need to mitigate climate change-induced heat stress in livestock and poultry in the Caribbean, given the deleterious effects it has on food and nutrition security. The temperature humidity index (THI) was used to assess the potential for heat stress on four types of livestock and poultry (broiler and layer chickens, pigs and ruminants) for three different agro-ecological locations in Jamaica. The THI was formulated specifically to each livestock type and was examined for 2001–2012 for seasonal and annual patterns of variability. Differences in THI were observed between summer (July to September) and winter (December to February) with some moderation due to agro-ecological location. Our results suggest that animals in ambient field conditions in Jamaica may already be experiencing considerable periods of heat stress even during the relatively cooler northern hemisphere winter months. Future patterns of heat stress relative to a 1961–1990 baseline were derived from a regional climate model when mean global surface air temperature is 1.5, 2.0 and 2.5 °C above pre-industrial levels. At 1.5 °C, marked increases were noted in THI and almost persistent year-round heat stress is projected for Caribbean livestock. Conditions will be exacerbated at the higher global warming states. Possible response strategies such as cooling technologies are discussed.  相似文献   
166.
A novel metric space for the clustering of back trajectories to be used in fine particle aerosol data analysis was proposed and evaluated. The metric is based on spatial and non-spatial variables incorporating great-circle distance, altitude and radon-222.Its performance was examined using the intra-cluster variation of measured and fingerprint apportioned aerosol mass as the quantitative criterion. The new metric was demonstrated to perform better than those based on great-circle distance, or a great-circle distance and altitude alone. The same criterion was applied to investigate the clustering performance as a function of the length of its back trajectories. The optimum back trajectory length was found to be dependent on the pollution source being considered.Performance tests, as well as the application of the new metric space to re-analysis of previously published results, were based on a three year long dataset comprising co-located aerosol fine particles (PM2.5) collection and hourly measurements of radon-222 concentration.The new metric space can easily be redefined to include other trace species.  相似文献   
167.
168.
Yosef Cohen 《Ecological modelling》2009,220(13-14):1613-1619
Methods for modeling population dynamics in probability using the generalized point process approach are developed. The life history of these populations is such that seasonal reproduction occurs during a short time. Several models are developed and analyzed. Data about two species: colonial spiders (Stegodyphus dumicola) and a migratory bird (wood thrush, Hylocichla mustelina) are used to estimate model parameters with appropriate log maximum likelihood functions. For the spiders, the model is fitted to provide evolutionary feasible colony size based on maximum likelihood estimates of fecundity and survival data. For the migratory bird species, a maximum likelihood estimates are derived for the fecundity and survival rates of young and adult birds and immigration rate. The presented approach allows computation of quantities of interest such as probability of extinction and average time to extinction.  相似文献   
169.
Aerial photography has been routinely used for several decades by natural resource scientists and managers to map and monitor the condition of forested landscapes. Recently, along with the emergence of concepts in managing forests as ecosystems, has come a significant shift in emphasis from smaller to larger spatial scales and the widespread use of geographic information systems. These developments have precipitated an increasing need for vegetation information derived from other remote sensing imagery, especially digital data acquired from high-elevation aircraft and satellite platforms. This paper introduces fundamental concepts in digital remote sensing and describes numerous applications of the technology. The intent is to provide a balanced, nontechnical view, discussing the shortcomings, successes, and future potential for digital remote sensing of forested ecosystems.  相似文献   
170.
Several published studies have examined skin-cancer prevalence in regions of the USA that have concentrations of arsenic above the USA drinking-water standard. Those studies with adequate exposure and health outcome data did not report any skin cancer cases. Because the USA's arsenic concentrations are relatively low compared to some other countries and the study populations are small, the absence of reported skin-cancer cases could be due to an absence of risk in USA populations or random variability from a predicted risk. We used the current EPA arsenic cancer slope factor (CSF) model, which is derived from Taiwanese populations exposed to high levels of arsenic, to predict the expected number of skin cancers. We then conducted a likelihood ratio analysis, which showed that a null hypothesis (no additional skin cancer risk from arsenic) was approximately 2.2 times more likely than the hypothesis that ingested arsenic causes the predicted rate of skin cancers. Although based on small numbers, our analysis of USA populations indicates that the CSF derived from arsenic exposure in Taiwanese populations may be an overestimate when applied to USA populations.  相似文献   
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