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991.
《Ergonomics》2012,55(12):1487-1500
Deviations from anticipated courses of events are often associated with accidents, while the effects of deviations that decrease productivity but do not obviously lead to human injury are less clear. A systemic approach to production and safety is introduced, and it is proposed that production deviations have effects that may lead to safety violations and personal injury. In addition, the relationship between observed and perceived production deviations from 12 senior (60–79 years old) males' routine work using three firewood processing machines is analysed. For simple machine work, perceived deviations were positively related to observed deviations per work cycle and inversely correlated to the perception of work efficiency. For more complex machine work it was more difficult to match observers' and operators' perceptions of deviations. Despite challenges in the production deviation concept, this approach offers a holistic understanding of the performance of human–machine-environment systems and complements assessments of deviations from safe working practice. 相似文献
992.
993.
Agileo Hernández-Gordillo Francisco TzompantziRicardo Gómez 《International Journal of Hydrogen Energy》2012
Highly active ZnS-UV was obtained in situ from ZnS(en)0.5 hybrid during the hydrogen formation using a methanol–water solution under UV irradiation. X-ray diffraction patterns and UV spectroscopy for both ZnS-UV and ZnS-400 obtained from the calcination of the ZnS(en)0.5 hybrid showed similar structural and photophysical properties; however, the efficiency of the ZnS-UV semiconductor was 7 times higher (4825 μmol h−1 g−1) compared to the ZnS-400. The highest H2 production was obtained using a UV lamp of very low intensity (2.2 mW cm−1) and it is attributed to a quantum size effect caused by the slow elimination of ethylenediamine (en) in the structural ZnS layer during the UV irradiation. 相似文献
994.
995.
介绍了龙煤集团鹤岗分公司鸟山矿井反供水输水管线工程。该工程外部地形条件复杂、途径沉陷不稳定区和多个村庄,主体工程竣工并且顺利完成通水试验,随着矿井达产后可以缓解周边地区用水紧张问题,为复杂地形矿区长距离输水管线设计和施工以及矿区总体规划设计提供了借鉴经验和新思路。 相似文献
996.
本文运用全寿命周期造价管理理论对某市政隧道照明方案进行比选,充分体现出了全寿命周期造价管理理论的科学性、重要性。 相似文献
997.
Hajime Masukawa Hidehiro Sakurai Robert P. Hausinger Kazuhito Inoue 《International Journal of Hydrogen Energy》2014
Heterocyst-forming cells of the cyanobacterium Anabaena sp. strain PCC 7120 ΔHup, lacking an uptake hydrogenase, photobiologically produce H2 by nitrogenase. Under N2-rich atmosphere, the nitrogenase activity declines in a rather short time due to the sufficiency of combined nitrogen. From the parental ΔHup strain, site-directed double-crossover variants, dc-Q193S and dc-R284H, were created with amino acid substitutions presumed to be located in the vicinity of the FeMo-cofactor of nitrogenase. Unlike the case for the ΔHup strain, H2 production activities of the variants were not decreased by the presence of high concentrations of N2 and they continuously produced H2 over 21 days with occasional headspace gas replacement. This property of N2 insensitivity is a potentially useful strategy for reducing the cost of the culture gas in future practical applications of sustainable biofuel production. This Anabaena strain has only the Mo-containing nitrogenase which reduces acetylene to ethylene, but the dc-Q193S variant also produced ethane at low but measurable rates along with greater rates of ethylene production. 相似文献
998.
Solving the integrated scheduling of production and rail transportation problem by Keshtel algorithm
Nowadays, scheduling of production cannot be done in isolation from scheduling of transportation since a coordinated solution to the integrated problem may improve the performance of the whole supply chain. In this paper, because of the widely used of rail transportation in supply chain, we develop the integrated scheduling of production and rail transportation. The problem is to determine both production schedule and rail transportation allocation of orders to optimize customer service at minimum total cost. In addition, we utilize some procedures and heuristics to encode the model in order to address it by two capable metaheuristics: Genetic algorithm (GA), and recently developed one, Keshtel algorithm (KA). Latter is firstly used for a mathematical model in supply chain literature. Besides, Taguchi experimental design method is utilized to set and estimate the proper values of the algorithms’ parameters to improve their performance. For the purpose of performance evaluation of the proposed algorithms, various problem sizes are employed and the computational results of the algorithms are compared with each other. Finally, we investigate the impacts of the rise in the problem size on the performance of our algorithms. 相似文献
999.
1000.
《International Journal of Hydrogen Energy》2019,44(57):30357-30366
Sewage sludge from a municipal wastewater treatment plant was fed into a microbial electrochemical system, combined with an anaerobic digester (MES-AD), for enhanced methane production and sludge stabilization. The effect of thermally pretreating the sewage sludge on MES-AD performance was investigated. These results were compared to those obtained from control operations, in which the sludge was not pretreated or MES integration was absent. The soluble chemical oxygen demand (SCOD) in the raw sewage sludge after pretreatment was 31% higher than the SCOD in untreated sludge (5804.85 mg/L vs. 4441.46 mg/mL). The methane yield and proportion of methane in biogas generated by the MES-AD were higher than those of the control systems, regardless of the pretreatment process. The maximum methane yield (0.28 L CH4/g COD) and methane production (1139 mL) were obtained with the MES inoculated with pretreated sewage sludge. Methane yield and production with this system using pretreated sewage were 47% and 56% higher, respectively, than those of the control (0.19 L CH4/g COD, 730 mL). Additionally, the maximum SCOD removal (89%) and current generation were obtained with the MES inoculated with a pretreated substrate. These results suggested that sewage sludge could be efficiently stabilized with enhanced methane production by synergistic combination of MES-AD system with pretreatment process. 相似文献