污水中化学需氧量速测法条件优化与实践

介绍了速测法测定污水中COD的方法。通过对该方法使用参数的优化选择,对优化前后结果进行了多次验证;对经典的重铬酸钾氧化滴定法与速测法进行了方法比对实验和对比实验,取得良好的效果,提高了准确度。     

人工边坡破裂面的最短路径搜索方法及其应用

文章运用Dijkstra最短路径算法确定土体中最危险的潜在破裂面,通过弹塑性有限元模拟基坑开挖过程, 计算土体的位移和应力以及评价基坑的稳定性。文中较详细地叙述了这种基于有限元分析技术和组合优化法来确定土坡中最危险的潜在破裂面的原理和实施过程,并给出了计算实例,进行了相应的讨论。     

基于直觉模糊AHP和灰色关联法的应急避难所选择

为了做好灾害事前应对,需要构建合理的应急避难所选择评价体系。针对传统的选择评价方法在确立权重时未消除主观因素的影响,并且利用TOPSIS方法不能确定评价对象关于优劣方案连线对称的排序等问题,提出基于改进直觉模糊AHP和灰色关联评价模型,首先利用非隶属度最大限度地减少人为偏差,然后利用各个避难所与最优方案的关联度来确定优劣,使得避难所选择最优化,减少资源闲置。通过实例,验证了该方法的合理性和有效性。     

Give them what they want or give them what they need? Ideology in the study of leadership

In recent years, a number of new, values‐based, or ideological models focusing on leader behavior have been proposed. These models include authentic, servant, character‐based, ethical, spiritual, and aesthetic leadership. In the present effort, we argue that these models, despite some differences in key dimensions, are tied together by a focus on moral behavior. The available evidence indicates that these models have only modest predictive power with respect to organizational performance criteria. More centrally, we argue that tests of these models are characterized by significant methodological problems with respect to both measurement and control. Moreover, these models suffer from some serious substantive concerns, including the explicit confounding of leadership and morality, discounting of system impacts, inappropriate assumptions about follower needs, and inappropriate scientific inferences. These models also fail to provide viable new approaches for leader development. We conclude that caution must be exercised when these models are employed as a basis for understanding leadership. Copyright © 2014 John Wiley & Sons, Ltd.     

Cadmium tolerance and accumulation in fifteen wetland plant species from cadmium-polluted water in constructed wetlands

Variations in cadmium (Cd) tolerances and accumulations among fifteen wetland plant species in moderately (0.5 mg·L⁻¹) and heavily (1.0 mg·L⁻¹) Cd-polluted wastewaters were investigated in constructed wetlands. Cd removal efficiencies from the wastewaters were more than 90%, and 23.5% and 16.8% of the Cd in the water accumulated in wetland plants for 0.5 and 1.0 mg·L⁻¹ Cd treatments, respectively. The variations among the plant species were 29.4-fold to 48.7-fold in plant biomasses, 5.4-fold to 21.9-fold in Cd concentrations, and 13.8-fold to 29.6-fold in Cd accumulations. The plant species were also largely diversified in terms of Cd tolerance. Some species were tolerant of heavy Cd stress, and some others were sensitive to moderate Cd level. Four wetland plant species were selected for the treatment of Cd-polluted wastewater for their high Cd accumulating abilities and relative Cd tolerances. Plant Cd quantity accumulations are correlated positively and significantly (P <0.05) with plant biomasses and correlated positively but insignificantly (P >0.05) with plant Cd concentrations. The results indicate that the Cd accumulation abilities of wetland plant species are determined mainly by their biomasses and Cd tolerances in growth, which should be the first criteria in selecting wetland plant species for the treating Cd-polluted wastewaters. Cd concentration in the plants may be the second consideration.     

基于合作博弈-云化AHP的地铁隧道施工方案选优

为了研究多专家对多方案的比选排序规则及数据特点,提出一种基于合作博弈-云化AHP算法处理该问题,并用以地铁隧道施工方案选择。方案选择对于控制施工成本,保证施工安全尤为重要。使用云模型嵌入AHP构建云化AHP模型对专家提供的不确定信息进行处理,得到在考虑实际工程背景下的方案偏好排序。使用合作博弈模型得到多个方案排序的综合排序。根据方案权重最大原则确定最优方案。分析了3位专家对3种隧道施工方案的偏好排序,其结果表明:对于给定的工程背景,盾构法施工是最优的。与现有4种模型进行对比,说明了其能更好地处理数据的不确定性,综合专家决策群意见,且数据量和计算量较小。     

能见度对个体疏散速度及路径选择的影响研

为提供火灾条件下人员疏散基础数据,基于4层教学楼疏散平台,开展了不同能见度环境下个体疏散实验,研究了能见度对人员疏散速度及路径选择的影响。研究结果表明:正常能见度条件下,人员的平均疏散速度为（2.37±0.23）m/s,个体间疏散速度差异明显,随着能见度降低,人员的平均疏散速度呈现均匀下降趋势,个体疏散速度最终均趋近于（0.36±0.10）m/s;人员水平疏散速度显著大于下行疏散速度,且水平疏散速度受能见度影响更大;当能见度较高时,人员以视觉作为寻路方式,倾向于选择自己最熟悉的路线进行疏散;能见度较低时,人员主要依靠触觉作为寻路方式,即借助墙或楼梯扶手进行疏散,此时人员的路径选择受到周围围挡物的共同作用。     

地铁火灾应急疏散路线规划与对策

为有效控制地铁内灾难发生、避免重大伤亡和损失,预先对地铁火灾进行模拟并制定相应疏散方案是必要的。首先,通过大量地铁案例分析,得出火灾发生概率、类型和部位。其次,对研究对象的数据进行收集,测绘形成图纸,并建立模型。最后,以北京地铁西直门站为例,在确定火灾情景后,利用PyroSim模拟地铁火灾,分析火灾发生时地铁内的环境温度、烟气浓度及可见度等因素对疏散的影响;根据测量所得人员参数,利用Pathfinder模拟疏散情况,分析疏散过程中的时间点、拥挤度和疏散瓶颈等不利因素;在火灾和疏散结果对比和分析中,提出地铁火灾疏散路线的规划及对策,建立多套消防救援方案,分析合理的救援路线,并对地铁内部的应急防控能力提出建议。     

一种改进的CSCA+PCA化工过程异常检测技术

为了解决化工过程异常检测时因参数众多且数据庞杂而导致一些异常无法被有效检出的问题,在Brownlee的克隆选择分类算法（CSCA）基础上,通过引入主成分分析（PCA）技术,进行数据降维和数据重整,探讨了人工免疫算法在化工过程异常检测中的适用效果和技术方案,以TE过程数据作为样本进行异常检测和分类实验。结果表明,过程异常数据的规模、属性的数目对CSCA异常检测效果具有明显影响,而通过主成分分析进行数据降维之后,CSCA检测效果有所提高;进一步的数据重整之后,CSCA对过程异常分类辨识的准确率可提升到85%以上;基于CSCA+PCA的数据降维及重构之后的过程异常检测技术方案,可以获得较高的异常检测准确率,从而一定程度上为化工过程安全运行提供技术保障。     

Consumption-based accounting of CO2 emissions in the sustainable development Goals Agenda

In 2017 the paper ‘The Sustainable Development Oxymoron: Quantifying and Modelling the Incompatibility of Sustainable Development Goals’ was published, showing that there is a conflict between socio-economic development goals and ecological sustainability goals using cross-country time-series data. The authors looked at production-based CO2 emissions to measure and model the 13^th SDG goal addressing climate change. Their models showed that production-based CO2 emissions were stalling or even decreasing in rich countries, which suggests that other countries are also likely to see stalling and decrease in their CO2 emissions once they become rich. However, this conclusion can be challenged when accounting for consumption-based CO2 emissions rather than production-based CO2 emissions. In this follow-up paper, we re-run some of the analyses performed in the original paper making use of consumption-based CO2 emissions. The analysis confirms the inherent SDG conflict between socio-economic and ecological SDGs. But, this new analysis demonstrates that from a consumption perspective the trend of stalling or decreasing CO2 emissions is reversed, with natural depletion costs being exported to poorer countries. Despite this new perspective on CO2 emissions, the conflict between SDG goals can still be avoided by making investments in public health, education and renewable energy, as suggested in the original paper.