江苏太湖地区水污染导致工业损失的初步估算

本文对污染损失计算所应包含的内容提出了新看法,主要分析了江苏太湖地区水污染对工业生产的影响,并重点对供水不足、水处理费用上涨、产品质量降低、地下水位降落等诸方面损失进行了估算。     

A note on non-parametric and semi-parametric modeling of wildfire hazard in Los Angeles County, California

This paper explores the use of, and problems that arise in, kernel smoothing and parametric estimation of the relationships between wildfire incidence and various meteorological variables. Such relationships may be treated as components in separable point process models for wildfire activity. The resulting models can be used for comparative purposes in order to assess the predictive performance of the Burning Index.

由河流流速、COD浓度估计河流COD衰减系数的经验模型

本文在综合分析影响河流ＣＯＤ衰减系数的各要素和系统调查相关资料的基础上,采用逐步回归分析方法得到了一个由河流流速、ＣＯＤ浓度估计河流ＣＯＤ衰减系数的经验模型,并通过方差分析检验了模型的可靠性。该经验模型简便,易于操作,既可应用于现有的河流水体,也可与水质模型相结合应用于变化后的河流水体,具有较强的应用性。     

液体储罐无组织排放估算方法

无组织排放量是环境影响评价中计算和确定卫生防护距离的重要因素。储罐的无组织排放来自于“小呼吸”损耗和“大呼吸”损耗。介绍了几种石油化工环境影响评价工作中应用的储罐无组织排放估算方法和计算机辅助计算方法。     

试论我国建设项目环境保护管理现状及改进方向

环境影响评价制度和“三同时”制度是我国建设项目环境保护管理的两项法律制度。本文较全面地论述了我国目前建设项目执行环境影响评价和“三同时”制度的现状和今后的改进方向     

关于河流污染事故的若干数学估计

为了预报突发河流污染事故的环境影响,对污染物迁移的相关估计和研究是非常必要的.以一维河流中的污染物迁移扩散模型为基础,讨论了几种不同情况下污染物浓度随空间的分布和随时间的变化.通过相应的数学推导,得到了若干简洁的估计公式:如污染物浓度的最大值点、达到某一浓度限值所经历的时间等.在获取足够的数据进行具体的数值模拟之前,由这些估计式可以得到污染物迁移过程中的一些重要特征量.     

Estimating Population Size in a Continuous-time Removal Experiment with a Known Sub-population Size Ratio

We study a continuous-time removal model for estimating the population size for a population in which a sub-population size ratio is known. The maximum likelihood estimate and the optimal martingale estimate of the population size are obtained; these are shown to be equivalent. A comparison between the proposed estimator and the maximum likelihood estimate which ignores the information on the known size ratio is made, using a simulation study. The asymptotic variances of these two estimators are also obtained, and a comparison between them is made. The sensitivity of mis-specification of the known size ratio is examined. We also apply the corresponding discrete-time model to the proposed continuous-time setting, and study the efficiency of the corresponding discrete-time type estimator relative to the proposed estimator.     

Statistical Issues in Assessing Anthropogenic Background for Arsenic

Conceptual and statistical issues surrounding the estimation of a background concentration distribution for arsenic are reviewed. How background area is defined and samples collected are shown to impact the shape and location of the probability density function that in turn affects the estimation and precision of associated distributional parameters. The overall background concentration distribution is conceptualized as a mixture of a natural background distribution, an anthropogenic background distribution and a distribution designed to accommodate the potential for contamination site samples being included into the background sample set. This concept is extended to a discussion of issues surrounding estimation of natural and anthropogenic background distributions for larger geographic areas. Finally, the mixture model is formally defined and statistical approaches to estimating its parameters discussed.     

五日生化需氧量测定中稀释倍数的估算

假定样品经过培养后耗氧率达５５％；推导出ＢＯＤ５稀释倍数Ｋ＝ＢＯＤ５／４．４，由稀释程度规定推导出ＢＯＤ５稀释倍数Ｋ＝（ＢＯＤ５－１）／４．０两种方法Ｋ基本相同，标准样品，工业废水经上述方法稀释后，测定结果比较满意，尤其对工业废水测定，既缩短了分析时间，又降低了测定误差。     

The failure of success in fisheries management

Law of the Sea negotiations and The Fishery Conservation and Management Act of 1976 create new options in fisheries management. Historical analysis of two major management programs in the United States of America, Columbia River chinook salmon (Oncorhynchus tshawytscha) and Pacific halibut (Hippoglossus stenolepis), shows two unresolved management problems. One is the innovativeness of fishermen in seeking ways to improve their harvests. The other is changing social priorities that are largely unpredictable and outside the control of fisheries managers. A method for analysis of patterning associated with management goals is illustrated. Since the general management goals are harvest improvement and more predictability, measures are used which show the adequacy of fit and reduction in variability between actual and predicted management outcomes.