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111.
M. Fehr K.A. Sousa A.F.N. Pereira L.C. Pelizer 《Environment, Development and Sustainability》2004,6(3):355-366
The research related here focuses on municipal situations where problems of sustainability may be defined and tackled on the basis of bottom-up management procedures with the participation of organized society. The aim is to build management models that may be implemented with reasonable administrative effort and cost. Implementation pursues the target of approaching a sustainable situation in the municipality. Environmental parameters for an ideal municipality with undefined geographical location are presented. For each parameter, a set of indicators is developed that can measure the prospect of sustainability. The indicators are defined in terms of numbers or literal concepts according to the possibility of measurement. Examples of management models are presented, which are able to approach the situation defined as sustainable by the indicators. The basic management tool is the learning curve of targeted communities, which is experimentally developed and applied. The indicators are grouped according to their range of applicability. 相似文献
112.
Richard H. McCuen Walter J. Rawls Bob L. Whaley 《Journal of the American Water Resources Association》1979,15(4):935-947
ABSTRACT: While the correlation coefficient and standard error of estimate are frequently used when comparing models of seasonal water yield, the following criteria may be more important in selecting one model from among several alternatives: rationality of the regression coefficients, the distribution of the residual errors, and the correctness of indicators of the relative importance of the predictor variables. These criteria were used to compare seasonal water yield models that were calibrated using multiple regression, stepwise regression, principal components regression, polynomial regression using a principal components rotation, and constrained pattern search. Hydrologic data from the Upper Sevier River basin in southern Utah were used to illustrate the comparative analysis process. The prediction equations used the April-July streamflow volume as the criterion variable. 相似文献
113.
Koningsveld EA 《Journal of Safety Research》2005,36(3):231-236
INTRODUCTION: There are many available models that help evaluate the effectiveness of safety and health measures, but many are complex and require input from many departments within an organization. There is a need to develop a more user-friendly model. METHOD: A participative model was developed that involves face-to-face interviewers with workers, maintenance department, purchasing department and health and safety experts. They were asked about costs, efforts, benefits, and effects of gauging the effects of prevention efforts. RESULTS: Cost effectiveness analyses are essential in all cases and can include whatever the end-user requires, whether it is a small or lasting improvement. Having management participate helps validate the data. CONCLUSIONS: Organizations who collaborate with someone with at least some skill in cost-benefit evaluations will find that they will be able to establish policies and procedures from the data. The end result is a calculation that is understood by all involved. 相似文献
114.
Bergström M 《Journal of Safety Research》2005,36(3):237-240
INTRODUCTION: Measuring the effect of safety and health on production is a difficult value to gauge. METHOD: This article introduces the Potential, which is an instrument for economic analysis that incorporates different changes in conditions. RESULTS: While there are a number of problems associated with methods to determine these calculations, this method is a good indicator of the effects of safety and health and produces more than 300 variables with much less input. IMPACT ON INDUSTRY: Organizations can use this method effectively to determine how safety and health measure can improve their bottom line. A positive business case is highlighted. 相似文献
115.
Gregory J. Buhyoff Stephen B. Williams W. David Klemperer 《Environmental management》1981,5(3):253-262
The purpose of this study was to collect specific information on the characteristics and intensity of local Blue Ridge Parkway use and to use that information to develop a recreation use model of local Parkway visitation. Data were obtained from a self-administered mail-back questionnaire sent to a random sample of people living in the 29 counties adjacent to the Parkway.We developed two recreation use projection/demand models that employ three variables (distance, alternative recreation sites, and population density) to predict visitation to different Parkway areas from various local origins. The derived model estimates indicated that about one-fourth of all Parkway visits in 1978 were one-day visits made by area residents. 相似文献
116.
117.
INTRODUCTION: Using data from the NASS General Estimates System (GES), the method of induced exposure was used to assess the effects of electronic stability control (ESC) on loss-of-control type crashes for sport utility vehicles. METHOD: Sport utility vehicles were classified into crash types generally associated with loss of control and crash types most likely not associated with loss of control. Vehicles were then compared as to whether ESC technology was present or absent in the vehicles. A generalized additive model was fit to assess the effects of ESC, driver age, and driver gender on the odds of loss of control. In addition, the effects of ESC on roads that were not dry were compared to effects on roads that were dry. RESULTS: Overall, the estimated percentage reduction in the odds of a loss-of-control crash for sport utility vehicles equipped with ESC was 70.3%. Both genders and all age groups showed reduced odds of loss-of-control crashes, but there was no significant difference between males and females. With respect to driver age, the maximum percentage reduction of 73.6% occurred at age 27. The positive effects of ESC on roads that were not dry were significantly greater than on roads that were dry. 相似文献
118.
Presence of congestion and confinement in offshore modules due to limited availability of space make Vapor Cloud Explosions (VCEs) a significant contributor to risk. There are several methods available for quantifying the blast overpressure generated over distances and time. The approaches range from one-dimensional analysis using correlation models to 3-D analysis using Computational Fluid Dynamics (CFDs). The correlation models are easy to use and well-suited for assessing a number of credible VCE scenarios. However, the overpressure results predicted by correlation models depend on a good estimate of flammable mass. This paper proposes a method to improve the estimation of flammable mass. The UKOOA Ignition model developed by the Energy Institute London is used to estimate the flammable mass; and is modified to account for the effect of mitigation measures on release rate. A directional probability for wind is also added to the model. The proposed model takes into consideration the platform geometry and offshore conditions for each scenario, release location and direction, and wind direction. An offshore production platform with three deck levels is presented as an example case. The flammable mass is also computed using CFD and the results are compared to that of the proposed and the conventional methods. The results show that the flammable masses for selected scenarios are better estimated by the proposed method, being much lower than estimated by the conventional method, though larger than the CFD results. This paper presents an interim result of a project undertaken to improve QRA studies for VCE events. 相似文献
119.
Matthew A. Williamson Brett G. Dickson Mevin B. Hooten Rose A. Graves Mark N. Lubell Mark W. Schwartz 《Conservation biology》2021,35(4):1174-1185
Private lands provide key habitat for imperiled species and are core components of function protectected area networks; yet, their incorporation into national and regional conservation planning has been challenging. Identifying locations where private landowners are likely to participate in conservation initiatives can help avoid conflict and clarify trade-offs between ecological benefits and sociopolitical costs. Empirical, spatially explicit assessment of the factors associated with conservation on private land is an emerging tool for identifying future conservation opportunities. However, most data on private land conservation are voluntarily reported and incomplete, which complicates these assessments. We used a novel application of occupancy models to analyze the occurrence of conservation easements on private land. We compared multiple formulations of occupancy models with a logistic regression model to predict the locations of conservation easements based on a spatially explicit social–ecological systems framework. We combined a simulation experiment with a case study of easement data in Idaho and Montana (United States) to illustrate the utility of the occupancy framework for modeling conservation on private land. Occupancy models that explicitly accounted for variation in reporting produced estimates of predictors that were substantially less biased than estimates produced by logistic regression under all simulated conditions. Occupancy models produced estimates for the 6 predictors we evaluated in our case study that were larger in magnitude, but less certain than those produced by logistic regression. These results suggest that occupancy models result in qualitatively different inferences regarding the effects of predictors on conservation easement occurrence than logistic regression and highlight the importance of integrating variable and incomplete reporting of participation in empirical analysis of conservation initiatives. Failure to do so can lead to emphasizing the wrong social, institutional, and environmental factors that enable conservation and underestimating conservation opportunities in landscapes where social norms or institutional constraints inhibit reporting. 相似文献
120.
Juan Tao Chengzhi Ding Jinnan Chen Liuyong Ding Sébastien Brosse Jani Heino Virgilio Hermoso Ruidong Wu Ziwang Wang Jiaxin Hu Rongxiao Che Xiaowei Jin Songhao Ji Dekui He 《Conservation biology》2023,37(3):e14036
The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43–0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25–29% of fish habitats, 16–23% of species, and 30–31% of priority conservation areas. Moreover, 6–21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered. 相似文献