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31.
A pedestrian safety education film titled And Keep on Looking and aimed at children ages 9 to 12 was evaluated in several cities. The results showed an increase in safe street crossing knowledge among 9- to 12-year-old Connecticut children who viewed the film, and some improvement in safe street crossing behavior among 9- to 12-year-old Seattle, Washington, children. Crash reduction was assessed in a 2-year, citywide field test conducted in Milwaukee. The field test indicated a crash reduction of more than 20% for 9- to 12-year-old children in Milwaukee compared with children in areas surrounding Milwaukee and children in comparison cities.  相似文献   
32.
    
This ex‐post facto/correlational study examines the relationships among the following variables: nurse manager motivation for power, achievement and affiliation (N=19), managerial leadership behaviors, staff nurse outcomes of job satisfaction, productivity and organizational commitment (N=221) and patient satisfaction (N=299). Results show that managerial motivation for power is negatively correlated with manager use of leadership behaviors and staff nurse job satisfaction but positively correlated with patient satisfaction. Managerial motivation for achievement is positively correlated with use of leadership behaviors as well as nurse job satisfaction, productivity and organizational commitment, and generally to patient satisfaction. Managerial motivation for affiliation reveals few significant positive or negative relationships with other variables. The researcher concludes that both power and achievement motivation of the manager influence staff and patient outcomes in health care in the 1990s. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT: Suspended sediment causes a range of environmental damage, including benthic smothering, irritation of fish gills, and transport of sorbed contaminants. Much of the impact, while sediment remains suspended, is related to its light attenuation, which reduces visual range in water and light availability for photosynthesis. Thus measurement of the optical attributes of suspended matter in many instances is more relevant than measurement of its mass concentration. Nephelometric turbidity, an index of light scattering by suspended particles, has been widely used as a simple, cheap, instrumental surrogate for suspended sediment, that also relates more directly than mass concentration to optical effects of suspended matter. However, turbidity is only a relative measure of scattering (versus arbitrary standards) that has no intrinsic environmental relevance until calibrated to a ‘proper’ scientific quantity. Visual clarity (measured as Secchi or black disc visibility) is a preferred optical quantity with immediate environmental relevance to aesthetics, contact recreation, and fish habitat. Contrary to common perception, visual clarity measurement is not particularly subjective and is more precise than turbidity measurement. Black disc visibility is inter‐convertible with beam attenuation, a fundamental optical quantity that can be monitored continuously by beam transmissometry. Visual clarity or beam attenuation should supplant nephelometric turbidity in many water quality applications, including environmental standards.  相似文献   
34.
ABSTRACT This paper describes the development and use of a mixed integer programming model for the planning of land disposal wastewater treatment facilities. Consideration is given to relevant construction and operating costs for land sites, transmission arteries, land acquisition costs, tangible benefits from land use, controls on aquifers, and various other engineering and technical constraints The model is used to determine which land disposal sites should serve which treatment plants, when initial construction should be initiated and completed, and when capacity expansion should occur. The model's application to the St. Louis Standard Metropolitan Statistical Area is illustrated and discussed.  相似文献   
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The phase of precipitation at the land surface is critical to determine the timing and amount of water available for hydrological and ecological systems. However, there are few techniques to directly observe the precipitation phase and many prediction tools apply a single temperature threshold (e.g., 0°C) to determine phase. In this paper, we asked two questions: (1) what is the accuracy of default and station optimized daily temperature thresholds for predicting precipitation phase and (2) what are the regions and conditions in which typical temperature‐based precipitation phase predictions are most suited. We developed a ground truth dataset of rain vs. snow using an expert decision‐making system based on precipitation, snow depth, and snow water equivalent observations. This dataset was used to evaluate the accuracy of three temperature‐threshold‐based techniques of phase classification. Optimizing the temperature threshold improved the prediction of precipitation phase by 34% compared to using 0°C threshold. Developing a temperature threshold based on station elevation improved the error by 12% compared with using the 0°C temperature threshold. We also found the probability of snow as a function of temperature differed among ecoregions, which suggests a varied response to future climate change. These results highlight a current weakness in our ability to predict the effects of regional warming that could have uneven impacts on water and ecological resources.  相似文献   
37.
    
Systematic conservation planning and Key Biodiversity Areas (KBAs) are the two most widely used approaches for identifying important sites for biodiversity. However, there is limited advice for conservation policy makers and practitioners on when and how they should be combined. Here we provide such guidance, using insights from the recently developed Global Standard for the Identification of KBAs and the language of decision science to review and clarify their similarities and differences. We argue the two approaches are broadly similar, with both setting transparent environmental objectives and specifying actions. There is however greater contrast in the data used and actions involved, as the KBA approach uses biodiversity data alone and identifies sites for monitoring and vigilance actions at a minimum, whereas systematic conservation planning combines biodiversity and implementation-relevant data to guide management actions. This difference means there is much scope for combining approaches, so conservation planners should use KBA data in their analyses, setting context-specific targets for each KBA type, and planners and donors should use systematic conservation planning techniques when prioritizing between KBAs for management action. In doing so, they will benefit conservation policy, practice and research by building on the collaborations formed through the KBA Standard's development.  相似文献   
38.
ABSTRACT: Techniques were developed using vector and raster data in a geographic information system (GIS) to define the spatial variability of watershed characteristics in the north-central Sierra Nevada of California and Nevada and to assist in computing model input parameters. The U.S. Geological Survey's Precipitation-Runoff Modeling System, a physically based, distributed-parameter watershed model, simulates runoff for a basin by partitioning a watershed into areas that each have a homogeneous hydrologic response to precipitation or snowmelt. These land units, known as hydrologic-response units (HRU's), are characterized according to physical properties, such as altitude, slope, aspect, land cover, soils, and geology, and climate patterns. Digital data were used to develop a GIS data base and HRIJ classification for the American River and Carson River basins. The following criteria are used in delineating HRU's: (1) Data layers are hydrologically significant and have a resolution appropriate to the watershed's natural spatial variability, (2) the technique for delineating HRU's accommodates different classification criteria and is reproducible, and (3) HRU's are not limited by hydrographic-subbasin boundaries. HRU's so defined are spatially noncontiguous. The result is an objective, efficient methodology for characterizing a watershed and for delineating HRU's. Also, digital data can be analyzed and transformed to assist in defining parameters and in calibrating the model.  相似文献   
39.
Elizabeth Anderson’s “pluralist–expressivist” value theory, an alternative to the understanding of value and rationality underlying the “rational actor” model of human behavior, provides rich resources for addressing questions of environmental and animal ethics. It is particularly well-suited to help us think about the ethics of commodification, as I demonstrate in this critique of the pet trade. I argue that Anderson’s approach identifies the proper grounds for criticizing the commodification of animals, and directs our attention to the importance of maintaining social practices and institutions that respect the social meanings of animals. Her theory alone, however, does not adequately address the role of the state in this project. Drawing on social contract theory to fill this gap, I conclude that the state’s role in regulating the pet trade should be limited to ensuring the welfare of animals in the stream of commerce, not prohibiting their mass marketing altogether.  相似文献   
40.
Standard procedures for evaluating environmental impact involve comparison between before and after conditions or scenarios or between treatment and control site pairs. In many cases, however, endogenous directional change (natural succession) is expected to occur at a significant rate over the period of concern, particularly for manmade systems such as impoundments. Static evaluations do not provide an adequate approach to such problems. A new evaluation frame is proposed. Nominal system behavior over time is characterized by a stochastic envelope around a nominal trajectory. We show that both the state variance and the sampling variance can change over time. In this context, environmental regulations can be framed as constraints, targets, or conformance to ideal trajectories. Statistical tests for determining noncompliance are explored relative to process variance, sample error, and sample size. Criteria are elucidated for choosing properties to monitor, sample size, and sampling interval.  相似文献   
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