Defining the Diurnal Pattern of Snowmelt Using a Beta Distribution Function

Snow is an important component of the hydrologic cycle for many regions worldwide. In addition to vital water resources, snowmelt can be important for forest ecosystem dynamics and flood risk. However, standard design events in the United States lack a design snowmelt event, including only precipitation events, though snowmelt has been shown to be larger than rainfall. In this article, we present a method using hourly snow water equivalent data to develop and test a function for representing the diurnal pattern of snowmelt. A two‐parameter beta distribution function is modified for the purposes of this study and found to fit the pattern of snowmelt well with a root mean squared error of 0.008. Soil moisture sensors were additionally utilized to assess the timing of the snowmelt water outflow from the base of the snowpack that supports the shape of the function, but suggests that the timing of losses recorded on snow pillows lag as much as 3 h. Further testing of the function showed the shape of the function to be accurate. The methods developed and tested in this paper can be applied for design purposes comparing snowmelt and rainfall events or to improve hydrological models investigating processes such as streamflow or groundwater recharge.     

基于均匀设计的边坡敏感性灰色关联分析

在边坡敏感性分析中,试验方法的选择对试验次数和试验效果起着至关重要的作用.与正交设计相比,均匀设计不仅能减少试验次数,而且能够获得较好的试验效果.本文以一土质边坡为例,选取容重、内聚力、内摩擦角、坡角及坡高5个因素进行均匀试验设计,并对其敏感性进行了灰色关联分析,结果表明:坡体的抗剪强度指标是影响土质边坡稳定性的最重要...     

生活垃圾卫生填埋场渗滤液处理系统工程设计

本文从工程的角度出发对垃圾填埋场渗滤液处理系统工程设计中的几个重点、难点计算参数,以及目前国内外几个典型垃圾填埋场的渗滤液处理工艺流程、处理效果做了介绍,并在此基础上提出了几点建议     

氟硅酸循环条件下氟吸收系统的设计及应用

在要求H2 SiF6 浓度 16 %～ 2 0 %的氟硅酸循环生产普钙的系统中 ,采用吸收室和湍球塔结合的方法 ,保证了尾气达标排放     

白洋淀水产养殖区水体富营养化评价及防治对策

为了研究白洋淀水产养殖对水环境的影响,评价白洋淀养殖水体所处的营养状态.进而为白洋淀水体富营齐化的防治提供科学依据,在此以2009年夏季监测数据为依据,采用修正的卡森指数法(TSIM)和综合营养状态指数法(TLI)分别对不同的养殖区域水体进行分析和讨论.其中修正卡森指数的评价结果为TSIM=67.62.已符合富营养化的标准;TLI=58.59,符合轻度富营养化标准,但部分养殖水体已经处于中度富营养状态.     

基于正交设计及EFDC模型的湖泊流域总量控制——以滇池流域为例

构建了基于正交设计-水质模拟-方案评价的污染物总量控制方案的方法体系,并应用于滇池流域.选择TN、TP作为总量控制指标,将滇池流域划分为6个子区单元,通过设计5水平（0%,5%,10%,15%,20%）6因素的正交试验表,得到25种不同削减方案;耦合EFDC模型模拟得到25种不同削减情景条件下湖泊水质的TN、TP浓度分布,计算各方案综合营养状态指数（TSI）,筛选符合中度富营养化标准（60     

A strategic design approach to develop sustainable product service systems: examples taken from the ‘environmentally friendly innovation’ Italian prize

The product service systems’ (PSS) sustainability potential is described in the framework of the new types of stakeholder relationships and/or partnerships, producing new convergence of economic interests, and a potential concomitant systemic resources optimization.In this perspective, it is argued that the design competencies should move towards those of the ‘strategic design’, thus introducing the concept of ‘strategic design for sustainability’: the design of an innovation strategy, shifting the business focus from designing (and selling) physical products only, to designing (and selling) a system of products and services which are jointly capable of fulfilling specific client demands, while re-orienting current unsustainable trends in production and consumption practices.Some examples of PSS are presented and discussed using the PSS categories ‘services providing added value to the product life cycle’, ‘services providing final results to customers’, and ‘services providing enabling platforms for customers’. The cases derive from an analysis of the ‘environmental friendly innovation’ yearly endowed prize submissions. The Politecnico di Milano University together with the Bocconi University and Legambiente (an environmental NGO) promotes the initiative in Italy.     

基于BP神经网络优化制备Cu-Ce/TiO_2及其光催化活性研究

采用Cu和Ce对TiO2进行改性,基于正交实验设计和BP神经网络研究了Cu-Ce/TiO2中Cu-Ce对TiO2的摩尔百分数、Cu-Ce/TiO2中CuCe摩尔比及Cu-Ce/TiO2烧结温度对Cu-Ce/TiO2光催化降解甲醛溶液性能的影响.同时,对Cu-Ce/TiO2制备方案进行了优化,并运用X射线衍射仪、扫描电子显微镜和紫外-可见分光光度计对最佳条件下制备的Cu-Ce/TiO2进行表征.结果表明,优化的制备条件为Cu-Ce/TiO2中Cu-Ce对TiO2的摩尔百分数为2.88%,Cu-Ce/TiO2中Cu-Ce的摩尔比为1∶1,Cu-Ce/TiO2的烧结温度为570℃.共掺杂Cu离子和Ce离子能有效避免掺杂TiO2晶格内部表层和近表层产生较多的位错,从而抑制晶格畸变增大;诱导TiO2中锐钛矿型晶体向金红石型晶体转变的能力增强,有效抑制电子-空穴对的复合,产生介电局域效应.     

结构可靠性的概率设计法综述

摘 要：【目的】概率设计法是结构可靠性设计法的核心。【方法】结构可靠性设计法按其提出时基于的表述方式可以分为非概率设计法,概率设计法。【结果】概率设计法具备可靠高效地满足工程实际需求的能力,因而倍受研究人员青睐。【结论】综述了目前国际上结构可靠性设计法领域现有的概率设计法,讨论了具有代表性的概率设计法的形式、优缺点和适用范围,展望了概率设计法的发展趋势。     

推进工业领域污染防治的实施战略研究

通过对工业污染防治面临的主要问题以及未来工业绿色发展态势和国家环境保护严峻形势进行深入分析,指出"十三五"是中国工业面临转型升级的重要战略机遇期,并重点从推动生产方式绿色化、发展节能环保产业、推进清洁生产和循环经济、强化污染防治力度等方面提出了工业行业在推进污染防治工作中的总体思路和发展战略。