建立在GIS平台上的环境应急监测管理系统模型设计——以廊坊市为例

以廊坊市为例研究了以GIS技术系统为支持平台的环境应急监测管理系统(EEMMS),结合实际给出了该系统的框架模型。EEMMS系统模型的应用可为突发性环境污染事故应急监测提供快速、可行的工作方法和模式,为环境事故应急指挥系统决策提供及时、有效、科学的技术支持。     

新陈代谢模型滑动指标检验及其在道路交通噪声预测中的应用

定义了灰色新陈代谢模型的滑动指标,实现了对新陈代谢模型各项精度指标及其稳定性的动态检验。对长春市1995年～2006年城市道路交通干线噪声监测的数据运用灰色系统理论,分别建立了3种预测模型,并对这3种模型的各项滑动指标、一步预测滚动指标分别进行了检验。     

环境空气质量评价法的适用性分析与比较

对几种具代表性的城市环境空气质量评价方法进行了优劣比较和适用性分析,认为在现有的综合污染指数法基础上进行改进的环境质量定性评价指数法,因其建立了与环境质量状况的关联,能够客观、科学的对环境空气质量状况进行定性评价,是一种具有比较优势的评价方法。     

RIP-N模型对官厅水库库滨带去氮效应的流域尺度模拟分析

以官厅水库库滨带为研究对象,构建适用于流域尺度岸边带去氮负荷估算的生态水文模型——RIP-N(Riparian-Nitrogen)模型,对官厅水库库滨带2007年3~9月间岸边带去氮效应进行分析.同时,在延庆水保站开展田间尺度的野外模拟实验,结合室内外试验分析和以往研究成果,对模型模拟结果进行验证.RIP-N模型包括土壤化学过程模拟和植物生长过程模拟.前者包括土壤反硝化模拟、硝化模拟和氨挥发模拟;后者包括植物净第一性生产力(net primary productivity,NPP)模拟、植物生产力分配模拟和植物营养元素吸收模拟.结果表明:①RIP-N模型模拟值与实验值的决定系数大于0.5,证明该模型在空间尺度模拟上的有效性及模拟结果的可靠性;②模型模拟结果表明官厅水库库滨带流域3~9月对N的总去除量为5.91×103t;③RIP-N模型对官厅水库库滨带去氮环境效益分析表明,当前库滨带土地利用格局中,滩地、林地和草地是去污效果较好的土地利用类型,3~9月对流域的去N量占流域总去N量的76.5%,在非点源污染防治中起到"汇"的作用;但是研究区中专属湿地的"汇"作用表现不明显,3~9月去N量仅占流域总去N量的5.9...     

基于ARIMA和XGBoost组合模型的交通事故预测

近年来交通事故及其损失严重影响社会经济的发展和人民生活的提高,交通事故预测可以为交通事故预防提供数据支持。基于自回归滑动平均(ARIMA)模型和极端梯度提升(XGBoost)模型,构建时间序列组合预测模型,对交通事故相关指标进行趋势预测。根据交通事故的特点,选定"事故起数""受伤人数""死亡人数"及"损失"4个指标。首先,根据自相关、偏自相关图确定ARIMA模型参数,根据AIC(赤池信息准则)值确定最终模型;然后,对4个指标的ARIMA模型预测结果的残差构建残差序列,对其进行XGBoost建模,得出修正后的残差预测值;最后,根据残差预测值和ARIMA模型预测值得出组合模型最终的预测值。实例结果表明,4项指标的混合预测模型的预测精度均优于单一的ARIMA模型和Holt-winters模型,其中以"受伤人数"和"死亡人数"的模型改善效果最为显著,"受伤人数"指标的平均绝对百分比误差降低了5.431 7个百分点,"死亡人数"指标的平均绝对百分比误差降低了3.625 9个百分点。     

基于马尔萨斯模型对钢铁企业伤害事故与工龄指数之间规律的研究

为了验证在钢铁企业中人的失效过程同服役年限有某种规律性的联系,采用马尔萨斯模型对人的服役年限--工龄与伤害事故频数之间的规律性进行机理推证.在对典型钢铁企业40年间工伤事故数据库中的1 465起伤害事故进行统计分析、建立回归模型后,结论显示伤害事故频数y与受害人员的本工种工龄x存在显著指数相关关系:y=167.13e0.012x、相关系数R=0.93,证实了马尔萨斯模型应用于"工龄-伤害事故频数"指数规律的准确性.改进后的指数规律模型对实际钢铁企业安全管理工作有着重要的研究价值和指导意义,且可以在其他领域中进行探索和推广.     

环境建设样板城内涵及评价指标体系研究

探讨了环境建设样板城提出的背景,提出环境建设样板城的基本概念及内涵,确定了环境建设样板城评价指标体系的制定原则,建立了由五大类九十项指标构成的环境建设样板城评价指标体系.     

Assessment of explosion risks caused by cone discharges when filling silos and containers with pellets

It is well known that during the filling of silos and containers with bulk material, so-called cone discharges can occur because of electrostatic charges. Whether or not cone discharges occur at all depends on whether the breakdown field strength of air under atmospheric conditions of 3 MV/m is reached at the silo and container inner wall. This in turn depends on the charge to mass ratio of the bulk, the bulk resistivity, the bulk density, the relative permittivity of the bulk material, the silo or container diameter and the filling rate. If cone discharges can't be avoided, the energy of cone discharges can be estimated according to the equation given in the relevant guidelines TRGS 727 (2016) and IEC/TS 60079-32-1 (2013). Therefore, the coarse fraction must be considered. As soon as the energy of the cone discharge is greater than or equal to the minimum ignition energy of the bulk material introduced, there is a risk of dust explosion. Here the fine fraction of the bulk material is relevant.The investigations described are a practical example how computer models can be used to assess the occurrence of cone discharges. It is calculated for which silo and container diameters and filling rates the critical field strength of 3 MV/m is reached. In these calculations the charge relaxation during pneumatic filling with bulk material is taken into account. The results of the computational modelling together with operational boundary conditions serve as a decision basis whether exclusion of incendive ignition sources is an adequate safety measure or whether further explosion protection measures must be considered. Finally, a brief overview of other possible explosion protection measures is given.     

Environmental Communication as a Discipline of Crisis

This essay interprets Cox's keynote as a call for environmental communication to reorient itself as a form of ideological criticism and identifies the potential pitfalls of heeding that call. First, the author revisits key arguments surrounding the practice of ideological criticism in Communication Studies and articulates their relevance to discussions about the mission and purpose of environmental communication. Second, he suggests that an uncritical embrace of the rationale for a “crisis discipline” may perpetuate problematic assumptions about communication, both as a social practice and as a scholarly discipline. Third, he argues that such problems may be sidestepped by making environmental crisis itself a central concept and object of environmental communication inquiry, such that environmental communication does not merely respond to crisis but becomes a discipline of and about crisis. A focus on the dynamics of crisis, the author concludes, entails a persistent concern with judgment in its political, scholarly, and pedagogical contexts.