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991.
Eleven million tonnes of waste are produced yearly by the European pulp and paper industry, of which 70% originates from the production of deinked recycled paper. Wastes are very diverse in composition and consist of rejects, different types of sludges and ashes in mills having on-site incineration treatment. The production of pulp and paper from virgin pulp generates less waste but the waste has similar properties to waste from the production of deinked pulp, although with less inorganics. Due to legislation and increased taxes, landfills are quickly being eliminated as a final destination for wastes in Europe, and incineration with energy recovery is becoming the main waste recovery method. Other options such as pyrolysis, gasification, land spreading, composting and reuse as building material are being applied, although research is still needed for optimization of the processes. Due to the large volumes of waste generated, the high moisture content of the waste and the changing waste composition as a result of process conditions, recovery methods are usually expensive and their environmental impact is still uncertain. For this reason, it is necessary to continue research on different applications of wastes, while taking into account the environmental and economic factors of these waste treatments. 相似文献
992.
Amit Kapur Hendrik G. van Oss Gregory Keoleian Stephen E. Kesler Alissa Kendall 《Journal of Material Cycles and Waste Management》2009,11(2):155-165
A country-level stock and flow model for cement, an important construction material, was developed based on a material flow
analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production,
import, and export data for different stages of the cement cycle. The United States currently supplies approximately 80% of
its cement consumption through domestic production and the rest is imported. The average annual net addition of in-use new
cement stock over the period 2000–2004 was approximately 83 million metric tons and amounts to 2.3 tons per capita of concrete.
Nonfuel carbon dioxide emissions (42 million metric tons per year) from the calcination phase of cement manufacture account
for 62% of the total 68 million tons per year of cement production residues. The end-of-life cement discards are estimated
to be 33 million metric tons per year, of which between 30% and 80% is recycled. A significant portion of the infrastructure
in the United States is reaching the end of its useful life and will need to be replaced or rehabilitated; this could require
far more cement than might be expected from economic forecasts of demand for cement. 相似文献
993.
Anders E. af Wåhlberg Author Vitae Lisa Dorn Author Vitae 《Journal of Safety Research》2009,40(3):197-201
Problem
Various indicators of health have been shown to be associated with traffic crash involvement. As general health is also related to absence from work, the latter variable may be more strongly related to crashes, especially for professional drivers.Method
Bus driver absence from work was analyzed in association with their crash records. Two British samples and one Swedish sample were used.Results
One of the British samples yielded fair correlations between crash record and absence, while for the other the effect was restricted to the first three months of driving. The Swedish data had effects in the expected direction but these were not significant.Discussion
The use of an indirect, overall measurement of health, may be a viable method for predicting the traffic crash involvement for professional drivers, although replications are needed in larger samples and other populations.Impact on industry
The use of absence records for the identification of at risk drivers would seem to be a simple and useful method for companies with major fleets, and it also shows the importance of promoting employee health and well being at work as a potential method of reducing the cost, not only of absenteeism, but also of crashes in company vehicles. 相似文献994.
Preferred modes of travel among older adults: What factors affect the choice to walk instead of drive? 总被引:1,自引:0,他引:1
Rebecca B. Naumann Author Vitae Ann M. Dellinger Author Vitae Author Vitae Amy E. Bonomi Author Vitae Author Vitae Robert S. Thompson Author Vitae 《Journal of Safety Research》2009,40(5):395-36
Introduction
There are many factors that influence older adults' travel choices. This paper explores the associations between mode of travel choice for a short trip and older adults' personal characteristics.Methods
This study included 406 drivers over the age of 64 who were enrolled in a large integrated health plan in the United States between 1991 and 2001. Bivariate analyses and generalized linear modeling were used to examine associations between choosing to walk or drive and respondents' self-reported general health, physical and functional abilities, and confidence in walking and driving.Results
Having more confidence in their ability to walk versus drive increased an older adult's likelihood of walking to make a short trip by about 20% (PR = 1.22; 95% CI: 1.06-1.40), and walking for exercise increased the likelihood by about 50% (PR = 1.53; 95% CI = 1.22-1.91). Reporting fair or poor health decreased the likelihood of walking, as did cutting down on the amount of driving due to a physical problem.Discussion
Factors affecting a person's decision to walk for exercise may not be the same as those that influence their decision to walk as a mode of travel. It is important to understand the barriers to walking for exercise and walking for travel to develop strategies to help older adults meet both their exercise and mobility needs. Impact on Industry: Increasing walking over driving among older adults may require programs that increase confidence in walking and encourage walking for exercise. 相似文献995.
Importance Measures (IMs) are used to rank the contributions of components or basic events to the system performance, e.g. its reliability or risk. Most times, IMs are calculated without due account of the uncertainties in the model of the behavior of the system. The objective of this work is to investigate how uncertainties can influence IMs and to develop a method for giving them due account in the corresponding ranking of the components or basic events. The uncertainties considered in this work affect the model parameters values and are assumed to be described by probability density functions. The method for ranking the contributors to the system performance measure is applied to the auxiliary feedwater system of a nuclear pressurized water reactor. 相似文献
996.
Obtaining knowledge about factors affecting health, safety and environment (HSE) is of major interest to the petroleum industry, but there is currently a severe shortage of relevant studies. The aim of this study was to examine the relative influence of offshore installation (local working environment) and company belonging on employees’ opinions concerning occupational health and safety. We analyzed data from a safety climate survey answered by 4479 Norwegian offshore petroleum employees in 2005 on the dimensions “Safety prioritisation”, “Safety management and involvement”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence” using one way analysis of variance (ANOVA), effect size and mixed model. The companies differed significantly for “Safety prioritisation”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence”. The local offshore installation explained more of the safety climate than the company they were employed in or worked for did. 相似文献
997.
Sinkings of fishing vessels, when accompanied by human loss, are accidents which lead to a great social upheaval, especially in the local area where they occur. In order to avoid or reduce these accidents, national governments must include in their legislation for this sector the appropriate safety measures. These resources and their distribution must be assigned in accordance with the needs of the accidentality, this requiring a detailed knowledge of the concentration of accidentality of a country’s fishing sector. In this context, the aim of the present work is twofold: first, to formulate a methodology for the fishing sector of a country, allowing the inequalities in the concentration of sinking accidents to be analysed; and second, to apply this methodology to the Spanish fishing fleet. Thus, two indices are constructed per region and type of fishing, for two variables: fishermen and vessels. Results are obtained both for the concentration of accidents and the associated Lorenz curves. An increase in the inequality in the spatial and functional distribution of these accidents is verified. 相似文献
998.
Most of the mesoscale models use roughness parameters to characterise the ground and to compute the surface stress. As the experimental determinations of the urban roughness parameters are rare and not very reliable, a new methodology based on microscale numerical simulations is presented here and the first results from two-dimensional simulations with different roof shapes are analysed.Firstly, it appears that the roof shape has a large influence : large difference in the Reynolds stress profile and in the roughness sub-layer thickness, enhancement of the exchanges at the roof level by buildings with attic. It also appears that the fetch necessary to obtain a constant flux layer is unrealistic compared to the real spatial homogeneity of quarters in European cities. Consequently, a new parameterisation of the urban ground-induced friction is to be developed without reference to the constant flux layer theory. 相似文献
999.
Eric E. Jorgensen Timothy J. Canfield Frederick W. Kutz 《Environmental monitoring and assessment》2000,63(1):199-210
Riparian buffer restorations are used as management tools to produce favorable water quality impacts, moreover among the many benefits riparian buffers may provide, their application as instruments for water quality restoration rests on a relatively firm foundation of research. However, the extent to which buffers can restore riparian ecosystems; their functionality and species composition, are essentially unknown. In light of the foregoing, two broad areas of research are indicated. First, data are needed to document the relative effectiveness of riparian buffers that differ according to width, length, and plant species composition. These questions, of managing buffer dimension and species composition for functionality, are of central importance even when attenuation of nutrient and sediment loads alone are considered. Second, where ecosystem restoration is the goal, effects to in-stream and terrestrial riparian biota need to be considered. Relatedly, the effects of the restoration on the landscape need to be considered. Particularly, at what rate do the effects of the riparian buffer on in-stream water quality, biota, and habitat diminish downstream from restored sites? Answers to these important questions are needed, for streams and watersheds of different size and for areas of differing soil type within watersheds. U.S. EPA-NRMRL has initiated as research project that will document the potential for buffers to restore riparian ecosystems; focusing on water quality effects, but also, importantly, documenting effects on biota. While substantial riparian buffer management initiatives are already underway, the extent of landscapes that influence riparian ecosystems in the eastern United States is large; leaving ample opportunity for this suggested research to provide improved buffer designs in the future. The ultimate goal of research projects developed under this paradigm of ecosystem restoration is to develop data that are needed to implement riparian buffer restorations in the mid-Atlantic and elsewhere, especially the eastern United States. 相似文献
1000.
Montane Meadows as Indicators of Environmental Change 总被引:1,自引:0,他引:1
Diane M. Debinski Mark E. Jakubauskas Kelly Kindscher 《Environmental monitoring and assessment》2000,64(1):213-225
We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change 相似文献