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451.
韩继明 《安全.健康和环境》2021,21(3):14-17
由某起爆炸着火事故案例,探讨液化烃装卸区域总图布置、车辆管理、设备设施、控制系统等方面存在的主要风险,并系统性探讨相应的解决措施。 相似文献
452.
提出了一种基于天轮传感器的新型箕斗提升定重装载系统;探讨以该系统为基础的无定量斗式定重装载形式、数据处理以及装载控制实现方法;研究以模糊神经网络为基础的智能数据处理与控制方法,有效解决了称重系统中因交叉灵敏度而导致的稳定性差、可靠性低等生产安全问题。实现老矿井箕斗提升系统特别是无定量斗式箕斗提升系统的定重装载改造,对煤矿提升系统安全、高效运行具有重要意义。 相似文献
453.
环境载荷与环境压强:环境压力指标及应用 总被引:2,自引:0,他引:2
一个国家的经济活动产生的环境压力与其具有的环境承载能力。决定了该国社会与经济发展的可持续状况。因此.测度环境压力和承载力是制定可持续发展目标和政策的必要条件之一。基于国家尺度的社会代谢物质流、地理面积和生态承载面积。可以构建出一个国家本国环境所承受的环境压力总量指标体系——环境载荷和环境压强;德国、荷兰、奥地利、日本和美国等五个工业国家的环境载荷和各环境压强总量指标若干年的实证计算和对比分析。可以发现.虽然美国的国内环境总载荷、人均物质总需求及人均生态足迹赤字等均是各国最高者.其环境压强却处于五国的最低端。与奥地利相近;以环境压强指标测度。除日本不明显外.其余四国的经济发展与本国环境压力之间在研究期(1975—1996)均显示出“脱钩”关系.即本国环境压强并没有随经济总量的增长而增加。为此.最后就环境问题的公平性和环境压力指标的优缺点进行简要讨论。 相似文献
454.
Arthur P. O'Hayre John F. Dowd 《Journal of the American Water Resources Association》1978,14(1):72-82
ABSTRACT: The effects of changing nutrient inputs through land use management, waste water treatment, or effluent diversion are not clear, and managers are discovering that decisions which were effective in reversing eutrophication for one lake are often unsuccessful when applied to another. Simple empirical relationships are often used to predict the impact of management decisions. Errors in estimation could result in either substantial costs for overdesign or failure to meet desired eutrophication levels. This paper presents and illustrates a methodology to evaluate the impact of land use and water resource management decisions on lake eutrophication. The problems of worth of additional information, and uncertainty of estimates were handled within a cost-effectiveness framework. The probability of exceeding a critical level of eutrophication was considered as a measure of effectiveness. The cost criterion is the expected value of opportunity costs, costs of analysis and costs of additional information. Uncertainty analysis techniques were used to estimate the effectiveness of various management alternatives. Bayesian methods can be utilized to determine the worth of additional information. The methodology was applied to Beseck Lake, Connecticut, and the cost and effectiveness measures estimated for a number of land management alternatives. Worth of additional information was not determined in this initial effort in uncertainty analysis for lake eutrophication management. 相似文献
455.
456.
随着我国工业化和城镇化的深入推进,人们对城市大气环境质量关注日益增加。连续五年对山西省太原市5个点位进行监测,考察降水中主要离子时间变异及大气干湿沉降规律。结果表明:太原市五个监测点年均干沉降量排序为太钢工业区坞城(东)桃园(市中)晋祠(景区)上兰(市郊),其中太钢年均沉降量是上兰的三倍。降尘量除了在不同点位差异较大外,相同点上不同季节也有较大波动,表现为各监测点春季和冬季降尘量为全年最高。而夏季由于降雨较多,干沉降最少。总体上,近五年各点干沉降量呈现逐年下降的趋势。湿沉降方面以桃园为市区代表分析,SO_4~(2-)、NO_3~-、Ca~(2+)和NH_4~+是太原市桃园降水中主要的无机离子,其加权平均浓度范围为3.1~19 mg/L,各离子浓度在干燥的冬春季较高,且近五年其浓度及沉降量快速增加。桃园降雨中SO_4~(2-)和NO_3~-仍然是最主要的致酸离子,SO_4~(2-)年均沉降量分别是NO_3~-、Ca~(2+)和NH_4~+的1.7、3.9、5.9倍。Ca~(2+)、NH_4~+和Mg~(2+)的中和因子分别是0.42、0.30、0.14,说明Ca~(2+)、NH_4~+对酸雨缓冲作用大于Mg~(2+)。2013~2017年太原市桃园降雨SO_4~(2-)/NO_3~-和NH_4~+/NO_3~-比值分别为1.7和0.3,表明酸雨类型由硫酸型向混合型发展,主要是近年来NO_3~-浓度增幅大于SO_4~(2-)和NH_4~+。总的来看,近些年太原市政府大力提倡节能减排带来明显效果,但工业厂矿区周边降尘污染依然严重,属于今后城市环境治理的重点。 相似文献
457.
Francisco Rebelo Correia da Silva Waldemar Karwowski 《International journal of occupational safety and ergonomics》2013,19(4):509-519
AbstractThis study reports on the development and validation of a new computer model for simulating human postures at work, and assessing the reaction forces and bending moments in 43 human articulation joints. The proposed model estimates the intradiscal pressure in the vertebral column in response to external loading forces encountered during human interactions with work objects or processes. The model was implemented in a self-contained interactive software package. The simulation results compare favorably with the reported experimental data, and provide reasonable confidence in the quality of the model. Its characteristics and its applications in evaluating physical task performance are also discussed 相似文献
458.
Inglis D. W. F. Choularton T. W. Dunning B. 《Water, Air, & Soil Pollution: Focus》2001,1(5-6):355-364
A continuous two-year atmospheric datasetcomprising gas and aerosol loadings from amountain site in northern England (Holme Moss,W1°5130 N53°320) is presented. The data are analysed with respect to three-dayback-trajectories that are grouped according to aclustering technique that allows speed, directionand curvature of the airmass track to beconsidered. The technique is successful inseparating the data into chemically distinctsubsets. Up to 29% of the variance in the datais explained by back-trajectory clusters. Slow trajectories are associated with highloadings especially for the oxides of nitrogen,which may imply a local source for much of thesuspended pollutant. The data suggest thatproduction of nitrate and sulphate is limited byoxidant availability at least in the winter. Itmay be possible to optimise the analytical powerof the technique by increasing the importance ofrecent airmass track in determining clusterallocation. This applies especially to the totalsulphur loading. 相似文献
459.
利用全国多雨、中雨和少雨典型区的自记雨量曲线和 Kinnel 方程:E=29.233·(1-e~(-(0.0477I+0.112)))计算出各点各次降雨的雨能值,并作出各区按月降雨(x)和雨能(y)的关系式:y=15.592x-171.630(多雨区),y=16.257x-280.279(中雨区),y=16.493x-107.676(少雨区)。将全国77个观测点的按月雨量资料计算出全年的雨能值。通过作图得到我国多雨和中雨区的年降雨量 P 和年雨能值 E 的关系:E=11.67p;和少雨区的关系:E=14.95P。从而可用此来估算全国各测点的雨能值。 相似文献
460.
Abstract: New criteria, pollutant load of unit area (PLUA), are developed for sustainable water quality management, which not only avoids degrading water quality but also considers the equity of development between different generations. A simulation‐optimization model is established to determine PLUA, in which uses the QUAL2E model to simulate pollutant transport and formulates a linear programming model to optimize the objective of maximal loads (carrying capacity). Two watersheds, the Touchen creek and the Keya creek, both in Taiwan, are taken as case studies. The PLUA criterion is applied to several existing projects which have passed environmental impact assessment (EIA). The results show that if the Hsinchu Science‐Based Industrial Park discharges wastewater to the Touchen creek, the total pollutant discharge of 85.6 kg/day exceeds the allocated load. Consequently, a waste reduction of at least 23.4% is required. Although these existing projects have passed EIA, most of them violate the criterion of PLUA and thus contribute to continued degradation of water quality. This study suggests developing PLUA as a part of the process of strategic environmental assessment (SEA) for watershed management plans and then applying it to EIA as a criterion for new project assessment. Furthermore, if carrying capacities of all pollutant discharges and resource uses can be translated into loads per unit of area, an integrated sustainable watershed management plan can be developed. 相似文献