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Abstract

Managing occupational safety in any kind of industry, especially in processing, is very important and complex. This paper develops a new method for occupational risk assessment in the presence of uncertainties. Uncertain values of hazardous factors and consequence frequencies are described with linguistic expressions defined by a safety management team. They are modeled with fuzzy sets. Consequence severities depend on current hazardous factors, and their values are calculated with the proposed procedure. The proposed model is tested with real-life data from fruit processing firms in Central Serbia.  相似文献   
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A conventional steel manufacturing process generates considerable amounts of reject streams and secondary raw material. These streams are either recycled back to the process or treated as waste. Recycling affects negatively on the production yield and on the controllability of unit operations. Waste represents considerable cost unless utilized in another production process as raw material. In these streams, there exists a potential to use the chemical elements more effectively. Therefore, it might be interesting to find an economical technical solution to collect the streams and increase steel production.

Investments on process equipment are typically evaluated using conventional economic figures, like payback time, Net Present Value (NPV) etc. The problem with these practices is, that they consider only numerical aspects. Non-numerical and non-economical criteria are hard to cater to the evaluation. Still, they may affect on the investment profitability in the long run. Such criteria include environmental friendliness or the aspects of process integration.

The article presents a comparison of a conventional steel manufacturing process with one reject stream processing alternative. A target in the process modification is to optimize the use of material and energy within the site. The comparison is based on a balanced set of criteria that affect on the efficiency of an investment. The use of these criteria is a part of the new methodology that has been developed to evaluate investments on integrated process sites. In addition to the criteria, the complete methodology includes: 1) connection of company’s strategic issues into technical design and decision making, 2) optimization of the process and calculation of process potentials (differences in the performance values between the existing process and the modified process) through the use of process integration methodologies and 3) use of decision-making aids. The research is a part of Finnish National Technology Program, “Process-Integration 2000–2004”.  相似文献   
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Ground level air pollution, especially fine particulate matter (PM2.5), has been associated with a number of adverse health effects. The dispersion of PM2.5 through the atmosphere depends on several mutually connected anthropogenic, geophysical and meteorological parameters, all of which are affected by climate change. This study examines how projected climate change would affect population exposure to PM2.5 air pollution in Poland. Population exposure to PM2.5 in Poland was estimated for three decades: the 1990s, 2040s and 2090s. Future climate conditions were projected by Regional Climate Model RegCM (Beta), forced by the general atmospheric circulation model ECHAM5. The dispersion of PM2.5 was simulated with chemical transport model CAMx version 4.40. Population exposure estimates of PM2.5 were 18.3, 17.2 and 17.1 μg/m3 for the 1990s, 2040s and 2090s, respectively. PM2.5 air pollution was estimated to cause approximately 39,800 premature deaths in the population of Poland in the year 2000. Our results indicate that in Poland, climate change may reduce the levels of exposure to anthropogenic particulate air pollution in future decades and that this reduction will reduce adverse health effects caused by the air pollution.  相似文献   
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Natural and man-made magnetic and electromagnetic fields are important factors in the contemporary life. The paper discusses the role of environmental magnetic and electromagnetic fields in origin and evolution of life. A brief review of the characteristics of Earth magnetic field, Earth magnetosphere, and their role as a shield for cosmic radiation follows. The role of endogenous and exogenous magnetic fields is discussed in respect of the clarification of the potential hazard and benefit of electromagnetic fields. The second part of the paper discusses the mechanisms of detection and response to exogenous electromagnetic fields, as well as threshold versus window hypothesis for mechanisms of interactions. Finally, the necessity of accurate dosimetry at the target site and the importance of relevant research and clinical protocols in studying biological responses are pointed out.  相似文献   
26.
Li C  Ji R  Vinken R  Hommes G  Bertmer M  Schäffer A  Corvini PF 《Chemosphere》2007,68(11):2172-2180
This study shows the important role of humic acids in the degradation of 14C and 13C labeled isomer of NP by Sphingomonas sp. strain TTNP3 and the detoxification of the resulting metabolites. Due to the association of NP with humic acids, its solubility in the medium was enhanced and the extent of mineralization of nonylphenol increased from 20% to above 35%. This was accompanied by the formation of significant amounts of NP residues bound to the humic acids, which also occurred via abiotic reactions of the major NP metabolite hydroquinone with the humic acids. Gel permeation chromatography showed a non-homogenous distribution of NP residues with humic acids molecules, with preference towards molecules with high-molecular-weight. Solid state 13C nuclear magnetic resonance spectroscopy indicated that the nonextractable residues resulted exclusively from the metabolites. The chemical shifts of the labeled carbon indicated the possible covalent binding of hydroquinone to the humic acids via ester and possibly ether bonds, and the incorporation of degradation products of hydroquinone into the humic acids. This study provided evidences for the mediatory role of humic acids in the fate of NP as a sink for bacterial degradation intermediates of this compound.  相似文献   
27.
Waste paper mill sludges originating from different effluent treatment and de-inking installations are complex mixtures of inorganic and organic particles. Due to their favourable physico-chemical, and microbiological characteristics, they may be conveniently reused for different purposes as such or after appropriate pretreatment. Sludges from the Slovenian paper industry were extensively tested for their chemical, stability and sealing properties. During the biodegradability tests, evolutions of greenhouse gases CO2, CH4 and H2S as well as the concentrations of released volatile organic acids, such as acetic, propionic, butyric, lactic and glycollic acids as the typical degradation products of organic materials, were measured. Some other important parameters of water leachates such as pH, redox potential, content of starch and leachable ions were also evaluated. The results indicate that most of them can be efficiently applied as alternative hydraulic barrier layers for landfill construction and covering instead of the more expensive clay due to their good geomechanical properties, chemical inertness and microbiological stability. Such replacement brings about considerable economical and ecological benefits as the waste is reprocessed as secondary raw material.  相似文献   
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A palaeoecological study was conducted to investigate past environmental conditions and vegetation dynamics around the southwestern Ljubljana Moor. In order to find potential regularities and/or dependencies among co-existent plant species through time, different machine learning methods were applied to pollen records from the cores taken at Bistra and Ho?evarica. The data comprised relative pollen frequencies of the most common plant genera/families at particular core depths that correspond to particular ages in the Early and Mid Holocene periods. The applied methods include equation discovery and hierarchical clustering. Both methods have found plausible and explainable relationships among identified plant genera/families.  相似文献   
30.
The annual cycle of migrating birds is shaped by their seasonal movements between breeding and non-breeding sites. Studying how migratory populations are linked throughout the annual cycle—migratory connectivity, is crucial to understanding the population dynamics of migrating bird species. This requires the consideration not only of spatial scales as has been the main focus to date but also of temporal scales: only when both aspects are taken into account, the degree of migratory connectivity can be properly defined. We investigated the migration behaviour of hoopoes (Upupa epops) from four breeding populations across Europe and characterised migration routes to and from the breeding grounds, location of non-breeding sites and the timing of key migration events. Migration behaviour was found to vary both within and amongst populations, and even though the spatial migratory connectivity amongst the populations was weak, temporal connectivity was strong with differences in timing amongst populations, but consistent timing within populations. The combination of diverse migration routes within populations and co-occurrence on the non-breeding grounds between populations might promote exchange between breeding populations. As a result, it might make hoopoes and other migrating bird species with similar strategies more resilient to future habitat or climatic changes and stabilise population trends.  相似文献   
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