Discrimination of sedimentary facies by association analysis

The ability of association analysis to discriminate sedimentary facies was tested on Purdy's modal analyses of modern sediments of the Great Bahama Bank. Purdy's data set has served in the past as a standard reference for evaluating various multivariate classification algorithms. In order to adapt Purdy's data to association analysis, the percent abundance of the 12 constituents was converted to binary form by dichotomizing each variable on its mean value. The results obtained by association analysis are virtually identical to those obtained by Purdy and other authors. The same four main sedimentary facies were discriminated; 86% of the samples were identically classified (97% when misclassified borderline cases are counted as matches); the total partition variance of the classification is only negligibly greater (4%); and the grouping of the variables yielded the same four groups. The rank order of the three division-attributes responsible for the sample classification is fines, oolites, and corals. Association analysis has been employed by other authors to differentiate meaningful facies groups in studies of ancient reef carbonates, modern reef sediments, and heavy minerals in stream sediments. In all these studies, the results were found to be compatible with those obtained by using the continuous quantitative measurements, indicating that qualitative binary data may often be sufficient for the purpose of facies discrimination in many branches of geology and that association analysis is an effective method for this purpose.     

LabVIEW设计中压力传感器的RBF神经网络温度补偿

在石油平台注水压力监测系统设计中 ,采用LabVIEW虚拟仪器平台 ,嵌入逼近能力强和收敛速度快的RBF神经网络 ,以人工环境实验数据为样本进行训练 ,实现了压力传感器的智能网络温度补偿。结果显示 ,此方法能够在压力、温度变化较大的恶劣环境下 ,获得很高的补偿精度。     

现代黄河三角洲粉土触变性研究及其应用

通过对现代黄河三角洲砂质粉土和粉质粘土触变性的对比试验研究，阐述了黄河口粉土的触变性。试验结果对解释粉土的失稳机制、解决工程地基的稳定性和防止地质灾害等具有重要的现实意义。     

Delayed geochemical hazard: Concept, digital model and case study

Delayed Geochemical Hazard (DGH briefly) presents the whole process of a kind of serious ecological and environmental hazard caused by sudden reactivation and sharp release of long-term accumulated pollutant from stable species to active ones in soil or sediment system due to the change of physical-chemical conditions (such as temperature, pH, Eh, moisture, the concentrations of organic matters, etc.) or the decrease of environment capacity. The characteristics of DGH are discussed. The process of a typical DGH can be expressed as a nonlinear polynomial. The points where the derivative functions of the first and second orders of the polynomial reach zero, minimum and maximum are keys for risk assessment and harzard pridication.The process and mechanism of the hazard is due to the transform of pollutant among different species principally. The concepts of "total releasable content of pollutant", TRCP, and "total concentration of active specie", TCAS, are necessarily defined to describe the mechanism of DGH. The possibility of the temporal and spatial propagation is discussed. Case study shows that there exists a transform mechanism of "gradual release" and "chain reaction" among the species of the exchangeable and the bounds to carbonate, iron and manganese oxides and organic matter, thus causing the delayed geochemical hazard.     

基于周仲瑛外感热病学术思想构建中医急诊诊治思路探析

目的：阐述周仲瑛教授外感热病学术思想对江苏中医急诊诊治思路的指导作用。方法：通过文献整理,归纳总结周教授外感热病学术思想;通过病案分析与数据挖掘的方法,分析周教授学术思想在中医急诊外感热病中的运用。结果：周教授创建的中医病机辨证理论是外感热病中医急诊辨治新体系的重要特征,主张审证求机,重视病机演变,提出截断逆转、祛邪外出两大治则。数据分析结果显示,江苏中医急诊学临床运用的外感热病诊治思路、方法与周教授的学术观点、学术理论相一致,学术思想一脉相承。结论：以周教授中医病机辨证理论为特征的外感热病中医急诊辨治新体系为临床诊治提供了纲领性指导,对中医急诊临床的学术影响举足轻重。     

0～6 h定量降雪(雨)预报技术及其在温哥华冬奥会中的应用

利用中尺度数值预报模式与雷达回波外推技术相结合,围绕SNOWV10项目的科学目标,在自动判识降水相态(雨、雪或雨雪混合物)基础上,利用雷达反演降雪(雨)关系,建立短时(0～6 h)定量降雪(雨)预报方法,并集成到GRAPES-SWIFT临近预报系统,为温哥华冬奥会提供实时场馆预报产品.从2010年2月冬奥会使用情况看,所建立的定量降雪(雨)预报技术,一定程度满足高纬度冬季降雪(雨)临近预报预警的需求,但降水(雨或雪)预报量级偏小,针对场馆的降水预报起止时间节奏偏差较大,各时次预报一致性有待改进.     

深海浮球内部气压对水下内爆波的抑制机理

深海潜器常携带中空浮球来为其提供浮力。陶瓷因其高强度、低密度等优点成为浮球的理想材料。然而,中空结构在外部高压环境下易发生内爆,产生的内爆波会对周围结构产生毁灭性损害。为了探索浮球内部初始气压对内爆波的影响,首先,利用气泡动力学对其不考虑球壳影响时进行理论分析,得到内爆波压力脉冲沿径向以指数?1 衰减,并指出其物理意义和隐含假设,进而从能量分析得到增加内压使压缩空气消耗的能量增加,从而减弱释放到水中的压力波能量;其次,采用三相流固耦合有限元模型进行计算,考虑水的可压缩性和球壳因挤压引起的脆性破裂的影响,得到更为接近实际的内爆压力的分布。由于两侧挤压球壳,外部的水在不断扩大的缺口处产生向内的射流,造成内部气体非球形塌缩,后续压力波呈现出与球壳碎裂方式有关的方向性差异。通过有限元模型对内部初始气压的研究表明,增加初始内部气体压力到 1 MPa 时,压力脉冲在球壳表面处下降了 15. 6%~24. 8%。这一结果表明,在几乎不增加浮球质量的条件下,增加内部初始气压具有很好地抑制近端内爆波强度的效果。     

林州市生态农业可持续发展浅论

生态农业是实施农业可持续发展的关键,文章用系统研究方法,从林州市生态农业可持续发展基础条件,现存问题入手,对生态农业可持续发展与对策进行了探讨。     

耗散大气中水平不均匀风场对内重力波传播的影响

采用包括耗散的射线跟踪方法,计算了在水平不均匀风场作用下,不同尺度重力波从对流层直至220km观测高度的传播,结果表明,垂直于重力波传播方向的风以及风剪切能够引起波射线的折射,从而导致重力波明显偏离初始传播方向.在强顺风场作用下,由于风场引起的捕获,大量重力波不能传播到观测高度.由于风场引起的多普勒频移,小周期的重力波在弱顺风条件下能够传播到观测高度.由于反射作用,强逆风场不支持周期低于约18min的较高频重力波的传播.而在弱逆风作用下,大部分中尺度范围重力波都能够传播到观测高度.本文统计了武汉电离层观象台的TID观测数据随热层风场的分布,统计结果与模拟结果符合较好.