环境监测中最优化抽样策略

本文分析了基本抽样程序,并用来解决环境监测的抽样优化问题。抽样过程形成马尔可夫链,通过划分接收水平和抽样区间建立抽样策略。计算每一组策略的目标函数的取值,找到备选策略中最小成本抽样策略即最优抽样策略。     

Water quality monitoring—Some practical sampling frequency considerations

Water quality monitoring involves sampling a population, water quality, that is changing over time. Sample statistics (e.g., sample mean) computed from data collected by a monitoring network can be affected by three general factors: (1) random changes due to storms, rainfall, etc.; (2) seasonal changes in temperature, rainfall, etc.; and (3) serial correlation or duplication in information from sample to sample. (Closely spaced samples will tend to give similar information).In general, these effects have been noted, but their specific effects on water quality monitoring network design have not been well defined quantitatively. The purpose of this paper is to examine these effects with a specific data set and draw conclusions relative to sampling frequency determinations in network design.The design criterion adopted for this study of effects due to the above factors is the width of confidence intervals about annual sample geometric means of water quality variables. The data base for the study consisted of a daily record of 5 water quality variables at 9 monitoring stations in Illinois for a period of 1 year.Three general regions of frequencies were identified: (1) greater than approximately 30 samples per year where serial correlation plays a dominant role; (2) between approximately 10 and 30 samples per year where the effects of seasonal variation and serial correlation tended to cancel each other out; and (3) less than approximately 10 samples per year where seasonal variation plays a dominant role. In region 2, either seasonal variation and serial correlation should both be considered or both ignored. To consider only seasonal variation introduces more error than ignoring it. These results are network averages (over variables and stations) from one network, thus results for individual variables may deviate considerably from the average and from those for other networks.Financial support for this study was provided, in part, by the U.S. Environmental Protection Agency, grant number R805759-01-0.     

PUBLIC EXPENDITURE PROGRAMS IN APPALACHIA AND THEIR IMPACT ON REGIONAL EMPLOYMENT1

ABSTRACT: The reduction of regional unemployment requires a sufficient demand for regional labor and the demand pattern must parallel that of supply. Due to the interdependency of Appalachian economy with the rest of the Nation, the leakage of the final demand imposed on a subregion of Appalachia is substantial. The more capital intensive the investment the higher the leakage which will lead to less demand for labor in Appalachia. While water resource projects are generally longterm projects which aim at structural changes in a regional economy, consumption expenditures induced by welfare payments or public employment programs are basically temporary measures for the rescue of unemployment. Average consumption and private investment programs may impose on Appalachia a larger material demand but the demand for the total regional labor, off-site and on-site combined, is estimated to be less than that from water resource investments. The public expenditure program for combating regional unemployment must be discretionary based on its purpose and its potential to generate optimum demand for labor which will be created by the pattern of regional resource distribution and interindustrial and interregional interactions. An interregional I/O model is best suited for analysis of this type.     

Integrating fire management into land-use planning: A multiple-use management research,development, and applications program

The traditional view of fire as a destructive agent requiring immediate suppression is giving way to the view that fire can and should be used to meet land management goals. Thus,fire control is being replaced by the more general concept offire management, which is based on the need to integrate fire policy with land management objectives. The social, economic, and ecologic effects of fire must be evaluated in the selection of land management alternatives.The activities of fire management organizations—fire prevention, control, and use of fire—must respond to needs of land management. Many agencies have developed fire organizations as separate entities that set their own objectives. The many land and resource managers who have recognized the need to incorporate fire considerations into land-use planning have so far lacked the techniques to do so.As a natural process, fire has an important function in forest and range ecosystems. Fire can greatly influence the quantity and quality of resource outputs; it is a two-edged sword that can either harm or benefit our goals, depending upon the complex effects of fire and the nature of our wants.The Fire in Multiple-Use Management Research, Development, and Applications (RD&A) Program was initiated by the U.S. Department of Agriculture, Forest Service, at the Northern Forest Fire Lab in Missoula to assist land managers. This profile explains what an RD&A program is; discusses its mission, goals, and approach to the problem; and tells why the approach involves federal laboratories, universities, and private research foundations.     

地震危险性分析程序SHA的敏感性分析

地震危险性分析程序ＳＨＡ自８０年代末推行以来,已在全国各省市的重大工程中发挥了很好的作用,为我国的国民经济建设作出了巨大的贡献。本文拟从几个不同的角度对它作一些测试和分析,以期地震界的专家们在今后的工作中使其更为完善,更为合理。     

B2B再循环物流网络优化模型研究

行业特性和技术约束致使一些制造企业产生大量的副产品和边角废料,对环境造成巨大压力.而可持续发展要求则促使制造企业寻求一种与自然生态环境和谐共处、资源良性循环的物流模式,构建再循环物流系统.因此,为了有效解决经济发展与环境的矛盾,促进产业间或产业内工业企业进行循环经济实践,设计具有生态柔性的B2B网络下再循环物流系统的结构模型.运用环境影响分析模型,分析再循环物流系统各个业务单元的环境影响因子.基于结构模型,运用混合整数规划方法,构建再循环物流系统多目标优化模型.该模型同时考虑了再循环系统的物流成本和外部环境影响;适合于多物料、单周期、有产能限制的再循环网络设施选址-分配问题.通过算例验证了模型的有效性.      

UNIVERSITY STUDENTS IMPLEMENT PUBLIC POLICY RURAL COMMUNITY ACTION WITH A WATER DEVELOPMENT PROJECT1

ABSTRACT: This report summarizes the findings of a ten week study made by the eight member Urban and Environmental Studies Program student staff of the Rock Creek Area Community Projects Board to assist the Village in its search for funds to improve its inadequate water and sewage systems. The ten year history of the Village of Rock Creek in its previous attempts to secure funding from outside sources is summarized. An analysis of federal funding programs’criteria is developed. Recommendations and a step by step analysis of how to precure these funds by the Village Council is presented. This report highlights the ten week activity which successfully produced earmarked federal funds for the Village's water project.     

Landowner Satisfaction with the Wetlands Reserve Program in Wisconsin

We evaluated ecological monitoring data and landowner perceptions to the federally funded Wetlands Reserve Program (WRP) in a three-county region in Wisconsin. We surveyed landowner satisfaction, involvement, participation, and use of the WRP restoration sites. We found that landowners are satisfied with the overall program (mean, 3.6 ± 0.2 [SE], on a scale of 1–5, with 5 being completely satisfied). WRP restorations significantly increased the area of wetland within the sites surveyed, the increase was primarily of fresh meadow (736.32 ha after restoration). Satisfaction is related to landowner participation during restoration and to the economic incentives provided by the WRP, Landowner satisfaction and the number of plant communities after restoration are unrelated to each other or to restoration and easement costs per hectare. Survey participants recommended some changes to the WRP, including a reduction in the tax rate of land enrolled in the WRP, approval for permanent deer stands, and increased communication with WRP officials during the restoration. Monitoring information collected for WRP restoration sites does not allow assessment of whether WRP sites are functionally equivalent to natural sites. We suggest that the WRP require a more rigorous monitoring program, including guidelines for invasive species control. Managers should also encourage collaborations with external researchers and consider restorations within an experimental framework.     

综采工作面粉尘浓度分布的数值解法

分析工作面流场和粉尘分布的特点，采用气──固两相流原理，导出描述综采工作面粉尘分布的数学模型。用数值方法一有限容积法求解数学模型，编制了计算综采工作面三维空间内风速和粉尘浓度分布的计算机程序。     

监测水和废水中油含量的水样采集方法

根据油在水体中存在形式的多样性，分布不均匀性及油对水体的污染情况，探讨了采样时在不破坏水体水文状态下前提下，采集漂浮油、分散油、乳化油和溶解油等多种形式的合理性，同时，根据均匀流场中点源油滴扩散微分方程的解，探讨了水和废水中含油水样的采样浓度，就均匀流场中的地表水而言采样深度≥５ｃｍ即可。