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排序方式: 共有443条查询结果,搜索用时 15 毫秒
141.
This paper presents an evaluation of the cost-effectiveness of a novel passenger monitoring system based on RFID technology for implementation onboard passenger ships. Such a system will be able to detect and keep track of passengers onboard the ship in emergency situations in order to provide crucial decision support to the officer in charge of evacuation. This will lead to increased safety and security on passenger ships. However, this increased safety will come at a certain cost. A methodology in line with Formal Safety Assessment is employed in order to assess the cost-effectiveness of the system, involving a thorough risk analysis. 相似文献
142.
Erik J. van Waveren 《Natural resources forum》2007,31(3):188-197
This paper examines the effects of growing land pressure on the distribution and quality of cropland allocations on customary tenured land (CTL) in Swaziland. Within the wider Sub‐Saharan context, the reform of indigenous tenure systems is now generally seen as a process of adaptation rather than replacement. The legal recognition of (existing and future) user rights is considered a practical way forward. This essentially rights‐based approach may divert attention from technical inadequacies indigenous systems may have, particularly under conditions of increasing land pressure. The case of CTL substantiates such shortcomings. CTL has seen a marked growth in population and land allocations since Independence. This had led to concerns on the land distribution efficiency in view of the improved agricultural production required to sustain the increasing number of rural households. By analysing historical changes in the number, size and quality of cropland allocations in selected rural communities, this paper demonstrates the occurrence of a high degree of inconsistency in cropland distribution at the community level, as well as inefficient land distribution at higher levels of scale. These shortcomings threaten the sustainability of the local agricultural production systems, and will need to be addressed in any meaningful reform process. 相似文献
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Environmental risk assessment of phosphonates,used in domestic laundry and cleaning agents in The Netherlands 总被引:2,自引:0,他引:2
Jaworska J Van Genderen-Takken H Hanstveit A van de Plassche E Feijtel T 《Chemosphere》2002,47(6):655-665
In the long-term cooperative project Voluntary Plan of Action (1990) between the Dutch Soap and Detergent Association (NVZ) and the Dutch Ministry of Housing, Spatial Planning and the Environment (VROM) environmental risk assessments of several main components of laundry cleaning formulations were completed. As a part of that project the environmental risk assessment of HEDP, ATMP, EDTMP and DTPMP phosphonates used in detergent applications has been carried out according to the EU Technical Guidance Document for Environmental Risk Assessment for New and Existing Chemicals. All PEC/PNEC ratios were well below 1. Results of this assessment based on the total industry volumes from 1995 and 1998 indicate that the environmental risk of these phosphonates is low in The Netherlands with properly functioning sewage treatment plants. 相似文献
146.
Shaobo Liang Armando G. McDonald Erik R. Coats 《Waste management (New York, N.Y.)》2014,34(11):2022-2027
Potato peel waste (PPW) as zero value byproduct generated from food processing plant contains a large quantity of starch, non-starch polysaccharide, lignin, protein, and lipid. PPW as one promising carbon source can be managed and utilized to value added bioproducts through a simple fermentation process using undefined mixed cultures inoculated from wastewater treatment plant sludge. A series of non-pH controlled batch fermentations under different conditions such as pretreatment process, enzymatic hydrolysis, temperature, and solids loading were studied. Lactic acid (LA) was the major product, followed by acetic acid (AA) and ethanol under fermentation conditions without the presence of added hydrolytic enzymes. The maximum yields of LA, AA, and ethanol were respectively, 0.22 g g?1, 0.06 g g?1, and 0.05 g g?1. The highest LA concentration of 14.7 g L?1 was obtained from a bioreactor with initial solids loading of 60 g L?1 at 35 °C. 相似文献
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Gregoire Timothy G. Ringvall Anna H. Ståhl Göran Næsset Erik 《Environmental and Ecological Statistics》2016,23(1):141-154
Environmental and Ecological Statistics - This paper considers conditioning on the size of the samples observed in post-strata following a two-stage sampling design. We argue that it is reasonable... 相似文献
150.
Interactions between dissolved organic matter (DOM) and bacteria are central in the biogeochemical cycles of aquatic ecosystems; however, the relative importance of biodegradable dissolved organic carbon (BDOC) compared with other environmental variables in structuring the bacterial communities needs further investigation. Here, we investigated bacterial communities, chromophoric DOM (CDOM) characteristics and physico-chemical parameters as well as examined BDOC via bioassay incubations in large eutrophic Lake Taihu, China, to explore the importance of BDOC for shaping bacterial community structures and co-occurrence patterns. We found that the proportion of BDOC (%BDOC) correlated significantly and positively with the DOC concentration and the index of the contribution of recent produced autochthonous CDOM (BIX). %BDOC, further correlated positively with the relative abundance of the tryptophan-like component and negatively with CDOM aromaticity, indicating that autochthonous production of protein-like CDOM was an important source of BDOC. The richness of the bacterial communities correlated negatively with %BDOC, indicating an enhanced number of species in the refractory DOC environments. %BDOC was identified as a significant stronger factor than DOC in shaping bacterial community composition and the co-occurrence network, suggesting that substrate biodegradability is more significant than DOC quantity determining the bacterial communities in a eutrophic lake. Environmental factors explained a larger proportion of the variation in the conditionally rare and abundant subcommunity than for the abundant and the rare bacterial subcommunities. Our findings emphasize the importance of considering bacteria with different abundance patterns and DOC biodegradability when studying the interactions between DOM and bacteria in eutrophic lakes. 相似文献