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521.
Logistic回归模型在尘肺发病预测与控制中的应 用研究   总被引:3,自引:1,他引:3  
目的:探讨Logistic回归模型在尘肺发病预测与控制 中的应用。方法:采用多元Logistic回归统计方法建立粉尘作业工人的接尘工龄(ET)、工 龄平均浓度(AEC)、粉尘毒性(T)三因素与尘肺发病概率的回归模型。结果:尘肺发病预 测与控制的回归模型为:P=1/{1+exp[-(-5.4707+0.0947ET+0.0024AEC+1.9784T )]},接尘工龄等三因素对尘肺发病影响的比数比分别为:1.0994(ET)、1.0024(AEC )和7.2310(T)。结论:所建立尘肺发病预测与控制的回归模型与所研究人群的符合率较 高,对今后预防尘肺发生的科学化管理与决策有较好的实用性和应用价值。  相似文献   
522.
Resource management as a key factor for sustainable urban planning   总被引:2,自引:0,他引:2  
Due to fast urbanization and increasing living standards, the environmental sustainability of our global society becomes more and more questionable. In this historical review we investigate the role of resources management (RM) and urban planning (UP) and propose ways for integration in sustainable development (SD). RM follows the principle of circular causation, and we reflect on to what extent RM has been an element for urban planning. Since the existence of the first settlements, a close relationship between RM, urbanization and technological development has been present. RM followed the demand for urban resources like water, energy, and food. In history, RM has been fostered by innovation and technology developments and has driven population growth and urbanization. Recent massive resource demand, especially in relation to energy and material flows, has altered natural ecosystems and has resulted in environmental degradation. UP has developed separately in response to different questions. UP followed the demand for improved living conditions, often associated to safety, good manufacturing and trading conditions and appropriate sanitation and waste management. In history UP has been a developing research area, especially since the industrial era and the related strong urbanization at the end of the 18th century. UP responded to new emerging problems in urban areas and became increasingly complex. Nowadays, UP has to address many objectives that are often conflicting, including, the urban sustainability. Our current urban un-sustainability is rooted in massive resource consumption and waste production beyond natural limits, and the absence of flows from waste to resources. Therefore, sustainable urban development requires integration of RM into UP. We propose new ways to this integration.  相似文献   
523.
This study describes the deforestation impact from three settlements, 5 de Junio, El Tigre, and 30 de Agosto, near the Madidi National Park in Bolivia. First deforestation rates along the road that connects the settlements and then deforestation within each settlement are examined. Landsat Thematic Mapper (TM) imagery from 1987, 1997, and 2000 were used to measure the deforestation. Face-to-face interviews were also used to collect detailed social and land-use information. Road-building and farming have been the major causes of deforestation in this region. The TM measurements indicate a high increase in the deforestation rate along the road in the area of study. The results also show a rapidly escalating deforestation rate in 5 de Junio, a potential high future deforestation rate in El Tigre, and a gradual deforestation increase in 30 de Agosto. The information provided by the settlers about clearing was compared with the imagery analysis. Generally, the settlers estimates were lower than the deforestation as derived from the imagery.  相似文献   
524.
525.
    
Abstract: Recent water sector reforms and increased scarcity and vulnerability of water resources, combined with declining public funding available for large scale infrastructure investment in the sector, have led to a greater awareness by the Government of Vietnam for the need to analyze water resource allocation and use in an integrated fashion, at the basin scale, and from a perspective of economic efficiency. In this study we focus on the development, application, and selected policy analyses using an integrated economic hydrologic river basin model for the Dong Nai River Basin in southern Vietnam. The model framework depicts the sectoral structure and location of water users (agriculture, industry, hydropower, domestic, and the environment) and the institutions for water allocation in the basin. Water benefit functions are developed for the major water uses subject to physical limitations and to constraints of system control and policy. Based on this modeling framework, we will analyze policies that can affect water allocation and use at the basin level, including both basin-specific and general macroeconomic policies.  相似文献   
526.
In river basins transformation from traditions of reactive flood defense to more adaptive management regimes is difficult. How regime components reinforce each other to set its development path may induce inertia and path dependency. Transformation may require profound shifts in the institutions, technologies, and personnel as well as the ecological, economic and social processes they influence in setting the basin's trajectory. Regime change has become an issue in Hungary following repeated failures of conventional management policies to handle a series of floods on the Tisza river starting in 1997. Increasing public participation pushed water policy debate toward more experimentation with alternatives, but implementation appears stalled. In this paper we review hypotheses about what factors are bridges or barriers to transformation and then use the Management Transition Framework to examine how the interactions linking action situations, operational outcomes, knowledge and institutions influenced the river management policy debate in Hungary from 1997 to 2009. Specifically we examined which factors characteristic of conventional Control vs. progressive Adaptive management regimes influenced these interactions in ways that contributed to or hindered transformation. We found that governance and social learning issues predominated, with lesser roles played by factors related to integration of sectors and different levels in the science and policy of river management.  相似文献   
527.
    
Journal of Material Cycles and Waste Management - Thermal pyrolysis of waste tires is an industrially beneficial method for material and energy recovery. Pyrolytic carbon black (CBp) is considered...  相似文献   
528.
Environmentally sound end-of-life management of Electrical and Electronic Equipment has been realised as a top priority issue internationally, both due to the waste stream’s continuously increasing quantities, as well as its content in valuable and also hazardous materials. In an effort to manage Waste Electrical and Electronic Equipment (WEEE), adequate infrastructure in treatment and recycling facilities is considered a prerequisite. A critical number of such plants are mandatory to be installed in order: (i) to accommodate legislative needs, (ii) decrease transportation cost, and (iii) expand reverse logistics network and cover more areas. However, WEEE recycling infrastructures require high expenditures and therefore the decision maker need to be most precautious. In this context, special care should be given on the viability of infrastructure which is heavily dependent on facilities’ location. To this end, a methodology aiming towards optimal location of Units of Treatment and Recycling is developed, taking into consideration economical together with social criteria, in an effort to interlace local acceptance and financial viability. For the decision support system’s needs, ELECTRE III is adopted as a multicriteria analysis technique. The methodology’s applicability is demonstrated with a real-world case study in Greece.  相似文献   
529.
    

The Covid pandemic has strongly affected the use of personal protective equipment (PPE) in the medical sector. Our aim was to assess the influence of Covid on PPE use within a German hospital by analyzing PPE use in four years prior to Covid and in 2020/2021. Numbers of items and mass of different types of PPE were determined based on procurement data. The results show that for the use of gloves the pandemic only had a small effect on the number of items. For body protection there was a clear trend toward a decrease in the number of items used in the years before the pandemic due to actions by the hospital toward a better environmental footprint which was partially reversed by the pandemic. The number of masks on the other hand doubled during the pandemic. Expressed in mass of PPE per patient and day, 15 g of masks, 121 g of gloves, and 183 g of body protection are used, resulting in a total of 319 g of PPE per patient and day. As medical waste has a specific treatment, no direct environmental effects of PPE use in hospitals in a region with well-developed waste treatment system are expected.

  相似文献   
530.
This study presents the microbiological characterization of the anaerobic sludge used in a two-stage anaerobic reactor for the treatment of organic fraction of urban solid waste (OFUSW). This treatment is one alternative for reducing solid waste in landfills at the same time producing a biogas (CH(4) and CO(2)) and an effluent that can be used as biofertilizer. The system was inoculated with sludge from a wastewater treatment plant (WWTP) (Río Frío Plant in Bucaramanga-Colombia) and a methanogenic anaerobic digester for the treatment of pig manure (Mesa de los Santos in Santander). Bacterial populations were evaluated by counting groups related to oxygen sensitivity, while metabolic groups were determined by most probable number (MPN) technique. Specific methanogenic activity (SMA) for acetate, formate, methanol and ethanol substrates was also determined. In the acidogenic reactor (R1), volatile fatty acids (VFA) reached values of 25,000 mg L(-1) and a concentration of CO(2) of 90%. In this reactor, the fermentative population was predominant (10(5)-10(6)MPN mL(-1)). The acetogenic population was (10(5)MPN mL(-1)) and the sulphate-reducing population was (10(4)-10(5)MPN mL(-1)). In the methanogenic reactor (R2), levels of CH(4) (70%) were higher than CO(2) (25%), whereas the VFA values were lower than 4000 mg L(-1). Substrate competition between sulphate-reducing (10(4)-10(5)MPN mL(-1)) and methanogenic bacteria (10(5)MPN mL(-1)) was not detected. From the SMA results obtained, acetoclastic (2.39 g COD-CH(4)g(-1)VSS(-1)day(-1)) and hydrogenophilic (0.94 g COD-CH(4)g(-1)VSS(-1)day(-1)) transformations as possible metabolic pathways used by methanogenic bacteria is suggested from the SMA results obtained. Methanotrix sp., Methanosarcina sp., Methanoccocus sp. and Methanobacterium sp. were identified.  相似文献   
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