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481.
The U.S. Environmental Protection Agency's National Exposure Research Laboratory is pursuing a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source through the air pathway to human exposure in significant exposure microenvironments. Current particulate matter (PM) emission models, particle emission factor model (used in the United States, except California) and motor vehicle emission factor model (used in California only), are suitable only for county-scale modeling and emission inventories. There is a need to develop a site-specific real-time emission factor model for PM emissions to support human exposure studies near roadways. A microscale emission factor model for predicting site-specific real-time motor vehicle PM (MicroFacPM) emissions for total suspended PM, PM less than 10 microm aerodynamic diameter, and PM less than 2.5 microm aerodynamic diameter has been developed. The algorithm used to calculate emission factors in MicroFacPM is disaggregated, and emission factors are calculated from a real-time fleet, rather than from a fleet-wide average estimated by a vehicle-miles-traveled weighting of the emission factors for different vehicle classes. MicroFacPM requires input information necessary to characterize the site-specific real-time fleet being modeled. Other variables required include average vehicle speed, time and day of the year, ambient temperature, and relative humidity.  相似文献   
482.
Environmental Science and Pollution Research - The 2030 United Nations Sustainable Development Goal (SDG) 13 agenda hinges on attaining a sustainable environment with the need to “take urgent...  相似文献   
483.
This study investigates the complexities involved in the relationships between perceptions of politics and work outcomes by examining the effects of political behavior on that relationship. More specifically, we suggest that political behavior may serve as a form of control or as a mechanism for coping with highly political organizational environments perceived by individuals to be aversive. As such, we propose moderating roles of self‐promotion and ingratiation on the relationships between perceptions of politics and the work outcomes of satisfaction with job in general, satisfaction with supervision, and intent to leave. It was hypothesized that increased exercise of self‐promotion and ingratiation behaviors would mitigate the negative effects of perceptions of organizational politics on those specific outcomes. Hypotheses were supported for the proposed relationships between self‐promotion and two of the work outcomes: satisfaction with supervision and intent to leave. Significant effects were also found for ingratiation; however, they were opposite to those proposed for the perceptions of organizational politics–intent to leave relationship. Implications of results and areas for future research are discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
484.
Most countries have many pieces of legislation that govern biodiversity, including a range of criminal, administrative, and civil law provisions that state how wildlife must be legally used, managed, and protected. However, related debates in conservation, such as about enforcement, often overlook the details within national legislation that define which specific acts are illegal, the conditions under which laws apply, and how they are sanctioned. Based on a review of 90 wildlife laws in 8 high-biodiversity countries with different legal systems, we developed a taxonomy that describes all types of wildlife offenses in those countries. The 511 offenses are organized into a hierarchical taxonomy that scholars and practitioners can use to help conduct legal analyses. This is significant amidst competing calls to strengthen, deregulate, and reform wildlife legislation, particularly in response to fears over zoonotic threats and large-scale biodiversity loss. It can be used to provide more nuance legal analyses and facilitate like-for-like comparisons across countries, informing processes to redraft conservation laws, review deregulation efforts, close loopholes, and harmonize legislation across jurisdictions. We applied the taxonomy in a comparison of sanctions in 8 countries for hunting a protected species. We found not only huge ranges in fines (US$0 to $200,000) and imprisonment terms (1.5 years to life imprisonment), but also fundamentally different approaches to designing sanctions for wildlife offenses. The taxonomy also illustrates how future legal taxonomies can be developed for other environmental issues (e.g., invasive species, protected areas).  相似文献   
485.
Environmental Fluid Mechanics - An internal wave is a propagating disturbance within a stable density-stratified fluid. The internal seiche amplitude is often estimated through theories that...  相似文献   
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