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741.
Offshore drilling for oil and gas has been conducted since the early 1900s. Oil and gas under the seabed continue to be an important part of the energy resources of the United States. The need to balance the value of these resources against the potential for environmental damage is an important concern. This article explains why and how the Minerals Management Service (MMS) of the US Department of the Interior uses research in physical sciences to help fulfill its environmental goals, and it provides background information on the role of physical sciences in decision-making for Outer Continental Shelf (OCS) oil, gas, and other minerals development. Established in the 1970s, the MMS Environmental Studies Program is a highly focused marine research program designed to provide the environmental information necessary for OCS energy and nonenergy minerals planning and development activities. The physical sciences research supported by MMS includes physical oceanography, oil-spill risk analyses, atmospheric sciences, and sand and gravel studies. Instead of giving a comprehensive review on physical sciences research in MMS, this article presents sample MMS studies and illustrates how these studies are utilized to support decision-making in environmental management.Published online Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
742.
Transgenic plants are now being used to develop pharmaceutical and industrial products in addition to their use in crop improvement. Using confinement requirements, these transgenic plants are grown and processed under conditions that prevent intermixing with commodity crops. Regulatory agencies in the United States have provided guidance of zero tolerance of these new industrial crops with commodity crops. While this is a worthy goal, it is theoretically unattainable. In spite of the best containment practices, there is a potential risk using any system of production due to unforeseen incidences including natural disasters or exposure to workers. The precautionary principle has been used for numerous regulated articles in addressing the potential risks of new products and technology based on a risk assessment in similar situations. We present here a risk assessment model that could be used as a start to develop an accepted model for the industry. The model is based on current risk models used for other regulated articles, but adapted for these types of products. This could be used to determine action levels in the event of an unintended exposure or to ensure that detection or confinement methods are adequate to avoid risks. As an example, aprotinin, a therapeutic protein now being produced in maize, was evaluated for potential risk to humans using this model.  相似文献   
743.
高速公路交通事故分析及预防对策研究   总被引:20,自引:8,他引:12  
利用济青高速公路 1998~ 1999年发生的 10 85起交通事故数据 ,在资料收集、处理和统计分析的基础上 ,对影响高速公路交通事故的人、车辆、道路环境、天气和交通量等主要因素进行了分析 ,并与国外的统计结果进行对比研究 ,预测出随着高速公路交通量的增长 ,事故率将会增加。此外 ,笔者针对影响高速公路事故因素提出了主动性、被动性预防对策 ,这些对策的实施将会减少高速公路事故的发生  相似文献   
744.
745.
The concentrations of heavy, trace elements and major ions measuredin the Uluda and Bursa aerosols were investigated to assess size distributions, spatial and temporal variability, sources and source regions affecting the composition of aerosols in Uluda and Bursa. A total of 81 samples were collected in two sites, one in Bursa city and another in the Uluda Mountain during two sampling campaigns. Daily samples were collected using a high volume sampler on Whatman 41 cellulose filters in Uluda, while three days interval samples were collected in Bursa using an automatic dichotomous sampler on PTFE Teflon filters. Samples were analysed for 15 trace and heavy metals (Al, Fe, Ba, Na, Mg, K, Mn, Ca, Cu), (V, Pb, Cd, Cr, Ni, Zn), and 4 major ions (SO4 2-, NO3 -, Cl-), (NH4 +) using ICP-AES, GFAAS, HPLC and UV/VIS Spectrophotometer,respectively. In general, concentrations of the metals measured inUluda aerosols were lower than those in Bursa. The concentrations of crustal elements were higher in summer than winter, while anthropogenic elements had higher concentrations in winter than summer. Most of the mass of crustal elements was concentrated in the coarse mode while the mass of the heavy metals was concentrated in the fine mode. Factor analysis revealed four factors with sources including crustal, industrial and combustion. Back trajectory calculations were used to determine long range contributions. These calculations showed that contributions were mostly from European countries, former Soviet Union countries, Black Sea and North Africa.  相似文献   
746.
Since the establishment, following World War II, of the World System, by which the affluent industrialized countries established various international assistance agencies (including the multilateral development banks, UN affiliates, and Bilaterals), these assistance agencies have invested very large sums in helping finance planning and construction of community sewerage and water supply facilities in the developing countries. However, much of this large investment has been ineffective and wasted, primarily because of the lack of understanding by the staff of the assistance agencies that the design criteria for the facilities must be modified to suit the socio-economic status of the developing country. The developing countries are relatively very poor in terms of available finances, hence cannot afford to emulate Western environmental standards and design practices, especially as related to operation and maintenance, hence much simpler approaches must be used. Experiences in several Asian countries are discussed, and a recommendation is made on how to go about resolving this problem.  相似文献   
747.
A relative significance factor (f i ) of an impact category is the external weight of the impact category. The objective of this study is to propose a systematic and easy-to-use method for the determination of f i . Multiattribute decision-making (MADM) methods including the analytical hierarchy process (AHP), the rank-order centroid method, and the fuzzy method were evaluated for this purpose. The results and practical aspects of using the three methods are compared. Each method shows the same trend, with minor differences in the value of f i . Thus, all three methods can be applied to the determination of f i . The rank order centroid method reduces the number of pairwise comparisons by placing the alternatives in order, although it has inherent weakness over the fuzzy method in expressing the degree of vagueness associated with assigning weights to criteria and alternatives. The rank order centroid method is considered a practical method for the determination of f i because it is easier and simpler to use compared to the AHP and the fuzzy method.  相似文献   
748.
PROBLEM: Motor-vehicle accidents are one of the major causes of injury in most motorized countries. Driver distractions have been suggested as a contributor to traffic accidents. Moreover, age of the driver seems to have a role in the relationship between distractions and car crashes. But very few studies have investigated the effect of driver's age on this relationship. This exploratory study investigated the association between distractions, both inside and outside the vehicle, and the increased risk of car crash injury among drivers across different ages. METHOD: This study used a case series design to analyze data routinely collected by the NSW police in Australia. A special focus of this study was on how drivers' age affects the risk of car crash injury, which was determined by using a well-documented risk estimation methodology. RESULTS: The results obtained indicated that drivers of all ages, on the whole, are more susceptible to distractions inside the vehicle than distractions coming from outside. Age was shown to affect the relationship between in-vehicle distraction and the risk of car crash injury. A separate analysis was also conducted on hand-held phone usage while driving with results supplementing previous findings reported in the literature. IMPACT TO INDUSTRY: Safety strategies to countermeasure in-vehicle distractions have been suggested and discussed.  相似文献   
749.
BACKGROUND: Safety teams have become a popular means to recognize and prevent injuries in the workplace. In fact, organizations, such as OSHA, NIOSH, NIEHS, DOE, and the Ohio BWC, not only encourage safety teams, but have implemented them in their organizations. However, safety teams may not be legal as defined by NLRB Act Sections 2(5) and 8(a)(2). OBJECTIVE: To determine whether safety teams are illegal labor organizations. METHODS: A review of government regulations, safety programs, and safety teams was performed to create a framework of what types of safety programs/regulations are requested and/or required by a variety of government agencies. Next, these requirements were compared to existing case law on illegal labor organizations as defined by the NLRB. RESULTS: Most safety teams and programs, even those implemented by the Federal Government, are illegal labor organizations as defined by NLRB Act Sections 2(5) and 8(a)(2). CONCLUSIONS: The Federal Government needs to amend existing legislation and develop a revision of the NLRB Act that would allow safety teams to function legally in organizations without having to meet intrusive, constricting guidelines that may inhibit the value of safety teams. IMPACT ON INDUSTRY: Organizations must be aware that safety teams may be valuable in reducing job-related accidents and injuries but they may be illegal labor organizations.  相似文献   
750.
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