炼油污水处理过程中关键控制因素分析

文章从灰色关联方法选择及分析原理入手，用某炼油厂2002全年的污水处理监测数据进行了灰色关联分析，通过运算分析得出了大量污水处理的关联数据。找出了影响出水水质指标的关键因素，对指导炼油污水进行分级控制做了有益的尝试。     

EVIDENCE OF CHAOTIC BEHAVIOR IN SINGAPORE RAINFALL1

ABSTRACT: This paper focuses on the investigation of the existence of chaotic behavior in the Singapore rainfall data. The procedure for the determination of the minimum number of variables essential and the number of variables sufficient to model the dynamics of the rainfall process was studied. An analysis of the rainfall behavior of different time periods was also conducted. The correlation dimension was used as a basis for discriminating stochastic and chaotic behaviors. Daily rainfall records for durations of 30, 20, 10, 5, 4, 3, 2, and 1 years from six stations were analyzed. The delay time for the phase-space reconstruction was computed using the autocorrelation function approach. The results provide positive evidence of the existence of chaotic behavior in the daily rainfall data. The minimum number of variables essential to model the dynamics of the rainfall process was identified to be 3 while the number of variables sufficient to model the dynamics of the rainfall process ranges from 11 to 18. The results also suggest that the attractor dimensions of rainfall data of longer time periods are higher than that of shorter time periods. The study suggests a minimum number of 1500 data points required for the computation of the correlation dimension of the rainfall data.     

EFFECTS OF IRRIGATION ON WATER QUALITY OF A SHALLOW UNCONFINED AQUIFER1

ABSTRACT: The ground water quality of a shallow unconfined aquifer was monitored before and after implementation of a border strip irrigation scheme, by taking monthly samples from an array of 13 shallow wells. Two 30 m deep wells were sampled to obtain vertical concentration profiles. Marked vertical, temporal, and spatial variabilities were recorded. The monthly data were analyzed for step and linear trends using nonparametric tests that were adjusted for the effects of serial correlation. Average nitrate concentrations increased in the preirrigation period and decreased after irrigation began. This was attributed to wetter years in 1978–1979 than in 1976–1977 which increased leaching, and to disturbance of the topsoil during land contouring before irrigation, followed by excessive drainage after irrigation. Few significant trends were recorded for other determinants, possibly because of shorter data records. Nitrate, sulphate, and potassium concentrations decreased with depth, whereas sodium, calcium, bicarbonate, and chloride concentrations increased. These trends allowed an estimation to be made of the depth of ground water affected by percolating drainage. This depth increased during the irrigation season and after periods of winter recharge. Furthermore, an overall increase in the depth of drainage-affected ground water occurred with time, which paralleled the development of the irrigation scheme.     

PARAMETRIC AND NONPARAMETRIC TESTS FOR DEPENDENT DATA1

ABSTRACT: Simulation and analytical results show that ignoring serial dependence can have serious effects on the performance of the t, sign, and Wilcoxen tests. In particular, the true significance levels of these tests are altered significantly from the intended nominal levels. Modifications for these tests are given and shown to have the correct significance levels. Furthermore, an estimate of serial correlation is suggested for binary data and evaluated by simulation. An application to the toxic contaminants data from the Niagara River concludes the paper.     

原生动物与BOD_5相关性的研究

本文着重研究了原生动物平衡期及密度与ＢＯＤ５浓度的相关性。研究结果表明，原生动物平衡期与ＢＯＤ５的浓度有着ｙ＝１５６２７·ｅ０２４０·ｘ的指数关系，相关性为显著相关；原生动物密度与ＢＯＤ５浓度有着ｙ＝１１３４＋００３６·ｘ的线性关系，相关性为高度相关     

A Jackknife Approach to Examine Uncertainty and Temporal Change in the Spatial Correlation of a VOC Plume

The application of geostatistics to spatial interpolation of time-invariant properties in ground-water studies (such as transmissivity or aquifer thickness) is well documented. The use of geostatistics on time-variant conditions such as ground-water quality is also becoming more commonplace. Unfortunately, the detection of temporal changes in spatial correlation through direct comparison of experimental semivariograms is difficult due to the uncertainty in sample semivariograms constructed from field data. This paper discusses the use of the jackknife approach to estimate confidence limits of semivariograms of trichloroethane (TC) and other volatile organic compounds (VOC) in contaminated ground-water in northern Illinois. Examination of the spread of the confidence limits about the semivariograms created from two types of sampling networks are discussed.     

水体中TOC与COD相关性研究

针对不同地区的地表水、生活污水和工业废水的TOC和COD进行了测试,对测定值进行线性回归分析。结果表明,不同类型的水体其TOC与COD均具有一定的相关性,尤其是生活污水和工业废水,TOC与COD相关性比较显著,在一定条件下可由测定的TOC值推算出COD值。     

银山矿田九区铅锌矿床深部成矿地球化学及预测

通过对银山矿田九区铅锌矿床 -60m～ -1 5 0m9-1 1和 9-2 5矿体垂向上成矿元素及伴生的指示元素特征研究 ,推测在 -1 5 0m以下九区铅锌矿床矿体仍将延伸     

太湖流域水灾演变与环境变迁的相关分析

新石器时期以来,太湖地区的水灾发生机制和表现形式严格受控于海、地、气系统的能量均衡和转换过程,具有明显的阶段性特征,遵循由海洋优势性向海面控制基准下陆源洪水的演变过程.愈接近现代,成灾和干扰因素愈趋复杂,逐渐呈现出水灾与环境相互反馈使水灾加深(岗身体系形成并完善,太湖形成并扩张以来),以及人类活动、水灾与环境三者间相互反馈使水灾频度加大等趋势(尤其自南宋以来).提出了相对高海面的水灾控制基面效应和太湖水灾扩张效应等观点.     

沙堆模型动力学特性与灾害系统演化预测研究

基于自组织临界性的理论框架,针对处于周期区与混沌区之间状态的灾害系统,研究其可预测性及预测方法.通过均匀和非均匀沙堆对比实验,发现两类沙堆模型表现出两种动力学行为--自组织临界性和准周期性.采用时序分析、功率谱分析和R/S分析等多种方法分析了两类系统的演化行为,反映了灾害系统的可预测特征;进一步提出了灾害预测的几个研究方向及方法.最后以极值统计法为例,介绍了其在两类灾害预测中的应用.