旧工业建筑再生利用项目施工安全的评价及改进

针对旧工业建筑再生利用项目施工过程中存在诸多安全隐患的问题,首先,结合此类项目遗留工业垃圾冗杂、施工场地狭窄、部分构件拆换、大型机械使用受限的施工特点从4MTE角度构建施工安全评价指标体系。然后,在考虑指标赋权的主客观综合性与评价工作的未确知性后,建立了基于结构熵权法与未确知测度理论的旧工业建筑再生利用项目施工安全评价模型,并通过工程实例验证该模型,得出的评价结果与实际情况相符。最后,结合未确知测度单因素指标测度函数的特点,提出了施工安全管理改进策略的制定方法。     

Evaluation of desiccant wheel and prime mover as combined cooling,heating, and power system

In this research heating, cooling and electrical demands of a residential tower are evaluated for Iran various weather conditions. For this purpose, several cities are selected as the representative of the specific weather conditions. To meet the cooling demand, desiccant cooling system plus alternative systems are applied. To analyze desiccant wheel, outlet humidity and temperature have been modeled. Also, the effect of rotational speed and regeneration temperature on entropy generation of the desiccant wheel has been studied based on the obtained results. It is deduced that the entropy generation may be increased by increasing the regeneration temperature and the rotational speed. To regenerate the desiccant wheel, to meet the electrical demand and also to provide heating load, prime mover in the form of internal combustion engine is selected. Since prime movers do not operate in the full load, their performance in the partial load has been evaluated. By taking into consideration the required regeneration heating, the number of required prime movers has been calculated based on the regeneration temperature and partial load for each city. The results show that the number of required prime movers is increased by increasing the regeneration temperature of the wheel.     

我国农村生活污水污染排放及环境治理效率

当前我国农村生活污水治理形势依然严峻.利用第二次全国污染源普查成果,分析了我国2017年农村生活污水排放情况,并基于熵值法和数据包络分析（DEA）模型从技术效率、经济效率两个角度对治理效率进行评价.结果表明:①我国农村生活污水中COD排放量约占生活源排放总量的50.8%,NH₃-N、TN和TP排放量分别占生活源排放总量的35.0%、30.5%、38.7%,污水及污染物排放去向以直排入水体、直排入农田和其他途径为主,三者占80%以上.②我国沿海用水量较大地区的水冲式厕所比例超过80%,且农村生活污水有效治理比例仅为11.0%,导致我国农村生活污水治理的技术效率仅为8.6%,且区域差异较大,其中有23个省份小于10%,技术效率普遍较低.③相比浙江省、上海市、山西省、内蒙古自治区、青海省、西藏自治区等地（经济效率均为1）,我国其他省份农村生活污水治理的经济效率有很大改善空间.农村生活污水中人均COD排放强度、人均NH₃-N排放强度与农村居民人均可支配收入之间的环境库兹涅茨曲线（EKC）均呈一定的倒“U”型关系,人均TN排放强度、人均TP排放强度与农村居民人均可支配收入之间的EKC则均呈“N”型特征,有波动上升趋势.研究显示,我国农村生活污水治理效率存在较大的提升空间,与城镇相比,农村的环境保护基础设施建设还比较落后,应以源头减量、分类处理、循环利用为导向,加强统筹规划,梯次推进,加快提升我国农村污水治理水平.      

Gender response and safe carrying load limit for sugar industry workers

This study investigates the safe carrying load limit in relation to gender of workers in the sugar industry. A total of 632 workers (male and female) were interviewed following a physiological and psycho-physiological methodology. All of these workers were in the age groups of 21–30, 31–40 and ≥41 years. In this study, for the physiological methodology, both field and laboratory data were collected, which included heart rate, heart rate variability, energy expenditure and maximum rate of oxygen consumption. Information regarding hemoglobin content, weight, age, lean body weight, etc., was recorded to know the physical health of the workers. In the psycho-physiological evaluation, load-carrying limits were determined by the psychophysical rating of the load by workers from the selected age groups. By considering the physiological stresses and psycho-physiological evaluation, the safe carrying load limit was determined in head and back mode for male and female workers as per their age groups.     

威布尔分布环境折合因子计算及其应用研究

目的对不同环境条件试验下的数据进行融合。方法针对应用最为普遍的威布尔分布类型的环境折合因子进行研究,给出威布尔分布环境折合因子的定义,根据极大似然估计法对威布尔分布环境折合因子进行计算。结果得出了相关环境折合因子的计算结果,在此基础上给出了应用环境折合因子进行数据融合的方法和步骤。结论应用威布尔分布环境折合因子可以合理的对不同环境下试验数据进行融合,达到扩大试验样本的目的。     

基于熵权模糊模型的土壤重金属生态风险评价

土壤重金属污染评价对于环境保护策略的制定和民众健康的防护具有重要意义。应用熵权、毒性系数和模糊数学构建了熵权模糊法评价模型,并以陕西省彬长煤化工业区为例,对其土壤重金属富集特征和潜在生态风险进行了评估。结果表明,土壤Cd、Co和Pb质量比较高,空间差异明显,建矿时间较长的工业园区土壤重金属潜在生态风险水平较高。熵权评价显示Cd为主要污染因子(权重为0.566)。模糊综合评价显示,研究区55.7%的样点为轻度污染,24.3%的样点为中度污染,无重污染和严重污染隶属样点。研究区污染程度有由轻度污染向中度污染过度的趋势。与传统污染评价指数相比,熵权法和模糊数学模型的联合应用有助于提高风险评价的准确性。     

The Impending Peak and Decline of Petroleum Production: an Underestimated Challenge for Conservation of Ecological Integrity

Abstract: In the last few decades petroleum has been consumed at a much faster pace than new reserves have been discovered. The point at which global oil extraction will attain a peak (“peak oil”) and begin a period of unavoidable decline is approaching. This eventuality will drive fundamental changes in the quantity and nature of energy flows through the human economic system, which probably will be accompanied by economic turmoil, political conflicts, and a high level of social tension. Besides being a geological and economic issue, peak oil is also a fundamental concern as it pertains to ecological systems and conservation because economics is a subsystem of the global ecosystem and changes in human energy‐related behaviors can lead to a broad range of effects on natural ecosystems, ranging from overuse to abandonment. As it becomes more difficult to meet energy demands, environmental considerations may be easily superseded. Given the vital importance of ecosystems and ecosystem services in a postpetroleum era, it is crucially important to wisely manage our ecosystems during the transition period to an economy based on little or no use of fossil fuels. Good policies can be formulated through awareness and understanding gained from scenario‐based assessments. Presently, most widely used global scenarios of environmental change do not incorporate resource limitation, including those of the Millennium Ecosystem Assessment and the Intergovernmental Panel on Climate Change. Considering the potential magnitude of the effects of peak oil on society and nature, the development of resource‐constrained scenarios should be addressed immediately. Ecologists and conservation biologists are in an important position to analyze the situation and provide guidance, yet the topic is noticeably absent from ecological discussions. We urge politicians, corporate chief executives, thought leaders, and citizens to consider this problem seriously because it is likely to develop into one of the key environmental issues of the 21st century.     

Leak location of pipelines based on characteristic entropy

The leakage of oil/gas pipelines is one of the major factors to influence the safe operation of pipelines. So it is significant to detect and locate the exact pipeline leakage. A novel leak location method based on characteristic entropy is proposed to extract the input feature vectors. In this approach, the combination of wavelet packet and information entropy is called “wavelet packet characteristic entropy” (WP-CE). The combination of empirical mode decomposition and information entropy is called “empirical mode decomposition characteristic entropy” (EMD-CE). Both pressure signal and flow signal of low noise and high noise of pipeline leakage are decomposed to extract the characteristic entropy. The location of pipeline leak is determined by the combination of the characteristic entropy as the input vector and particle swarm optimization and support vector machine method (PSO-SVM). The results of proposed leak location method are compared with those of PSO-SVM based on physical parameters. Under the condition of high noise, the results of proposed leak location method are better than those of PSO-SVM based on physical parameters.     

Setting conservation priorities for migratory networks under uncertainty

Conserving migratory species requires protecting connected habitat along the pathways they travel. Despite recent improvements in tracking animal movements, migratory connectivity remains poorly resolved at a population level for the vast majority of species, thus conservation prioritization is hampered. To address this data limitation, we developed a novel approach to spatial prioritization based on a model of potential connectivity derived from empirical data on species abundance and distance traveled between sites during migration. We applied the approach to migratory shorebirds of the East Asian‐Australasian Flyway. Conservation strategies that prioritized sites based on connectivity and abundance metrics together maintained larger populations of birds than strategies that prioritized sites based only on abundance metrics. The conservation value of a site therefore depended on both its capacity to support migratory animals and its position within the migratory pathway; the loss of crucial sites led to partial or total population collapse. We suggest that conservation approaches that prioritize sites supporting large populations of migrants should, where possible, also include data on the spatial arrangement of sites.     

A link between ecological diversity indices and measures of biodiversity

The practice of environmental planning and protection frequently necessitates the quantification of ecological diversity. Traditional ‘ecological diversity indices’ are based on the abundances of species present. However, such indices are insensitive to taxonomic or similar differences. With equal species abundances they measure the species richness (species number) only. Conversely, so-called ‘biodiversity indices’ are based on species differences, but are insensitive to the abundance conditions. The quadratic entropy index is the only ecological diversity index, the value of which reflects both the differences ‘and’ abundances of the species. When a species list is given without abundance data, then, using the quadratic entropy index and postulating equal abundances, one gets the only biodiversity index derived from a traditional ecological index of diversity. Its extensive form is identical with the sum of differences or distances between the species present. This index trivially satisfies set monotonicity, an important property for biodiversity indices.