浅谈齐齐哈尔市大气环境污染特征及其防治对策

齐齐哈尔市城区大气环境污染物主要为降尘、可吸入颗粒物(PM10)、SO2、NO2。其中降尘、PM10为首要污染物,降尘、PM10污染源来自煤烟尘、城市扬尘、机动车尾气尘等方面,属于复合污染类型,同时,人为活动所形成的二次扬尘正成为城市颗粒物污染的主要来源。因此,控制城区大气污染必须采取综合措施。     

A statistical study of the quality of surface water intended for human consumption near Valencia (Spain)

Water quality in the European Union is subject to legislation through directives that are applicable in all Member States. The directives specify a set of physical and chemical parameters that should be regularly controlled using a network of sampling points, with sampling based on the intended use of the water. This paper presents the results of a statistical comparison of the quality of water intended for human consumption at two different locations (the Canal de Benagéber and the Canal Júcar-Turia) near the town of Valencia (Spain). These are currently the only canals that could supply Valencia and other nearby towns with drinking water. The parameters considered in this paper are the ones specified in the European directives for determining the quality of water intended for human consumption. These directives specify that the 95th percentile of the distribution of each parameter should be used to assess water quality, so accurate estimation of these percentiles was essential in this paper. We found statistically significant differences among locations in chlorides, sulfates, temperature, coloration, and manganese, but the results varied depending on the statistical tests that we used; parametric methods gave better results than nonparametric methods.     

现代统计信息分析技术在安全工程方面的应用——常用统计量的矩阵表示

介绍了常用统计量矩阵的基础知识,以及日常统计工作中常用的参数进行矩阵化的方法。