Automatic classification of volcanic earthquakes by using Multi-Layered neural networks

The application of neural networks as classifiers of seismic events is described with the aim of developing an automatic system for the classification of explosion quakes at the Stromboli volcano. The architecture of the network that we trained to identify four different classes of shocks was a Multi-Layer Perceptron, using the Back Error Propagation algorithm. Five different approaches for representing the information embedded in the seismograms, both in the time and in the frequency domain, were considered, and the results compared. The direct use of the time series of the shocks was not satisfactory. The auto-correlation function worked well, but in some cases it was misleading. A better performance was obtained with a frequency domain representation. Finally, the use of the envelope function did not work well. Combining parameters such as the auto-correlation and envelope functions can improve one source of error, but it may introduce new ones. The performance obtained highlights the importance of the data attributes used for the training of the network. Topologies with eight neurons in a single hidden layer gave, on average, the best results among the considered neural network structures. The overall results provide a large number of events (89% with the best performance) correctly classified, indicating that this automatic technique is reliable, and encouraging further applications in the field of volcanic seismology.     

人工神经网络在白云岩类型识别中的应用

利用地球化学数据,运用人工神经网络方法对美国密苏里州东南Ｂｏｎｎｅｔｅｒｒｅ组（寒武纪）滨海相的白云岩进行了分类、识别,判别率达１００％,结果表明,该方法性能良好,可望成为岩石分类、判别的有效手段。     

The developmental characteristics and strategic ideas of urbanization in China

Since cities and towns are places where those nonagricultural industries are centralized, urbanization is greatly interrelated with industrialization and de-agriculturalization. By means of this kind of interrelationship, Chinese urbanization level may be estimated with the formulas: P1=I1/I0/u0, Pr = N1/N0/u0. The urbanization after the founding of the People's Republic of China can be divided into the following 5 stages: the stage at the out set of industrialization (1949-1957); the high-speed urbanization stage (1958-1960); the first counter-urbanization stage (1961-1965); the second counter-urbanization stage (1966-1976); and the high-speed urbanization stage (1978-now). The characteristics of Chinese urbanization are: the industrialization launched by the government; the simultaneous development of urbanization of cities and urbanization of rural areas; the quite low capability of urbanization to absorb nonagricultural labor force; the incoordinate development of cities, etc. Before establishing a     

基于网络药理学与分子对接技术探讨青蛇方外用治疗湿疹的作用机制

目的：基于网络药理学与分子对接技术探讨青蛇方外用治疗湿疹的作用机制。方法：应用TCMSP和UniProt数据库平台查询青蛇方组方的有效活性成分及靶基因,与疾病靶基因取交集后构建蛋白质-蛋白质相互作用(PPI)网络;应用DAVID数据库,对潜在核心作用靶点基因进行基因本体（GO）功能、京都基因与基因组百科全书（KEGG）通路富集分析。利用分子对接原理论证青蛇方生物活性成分与核心靶点的分子结合能力。结果：筛选出青蛇方有效成分63种,作用靶点99个;主要有β-谷甾醇、2,4,7-三羟基-9,10-二氢菲、靛蓝素、豆甾醇、色氨酸等关键成分;转录因子AP-1（JUN）、肿瘤坏死因子（TNF）、原癌基因（RELA）、干扰素γ（IFNG）、转化生长因子-β1（TGF-β1）等核心基因。关键信号通路有癌症信号通路、恰加斯病通路、弓形体病通路、脂质和动脉粥样硬化通路等,分子对接结果显示活性成分与核心靶点基因结合能力较强。结论：青蛇方外用可以通过多种活性成分、多种通路有效抑制免疫炎症反应,促进免疫系统正常运行,从而达到治疗湿疹的目的。     

Estimation of runoff distribution within river systems: Application to the Lena Basin (Siberia)

A channel account approach is proposed to estimate longitudinal changes in runoff along large river systems. This new method provides a quantitative basis for describing the fluvial transport of suspended particulate material and dissolved substances. This method includes an evaluation of basic elements of water balance in separate sections of the river network and subsequent correction of channel accounting equations for the entire system using a maximum likelihood principle. To calculate water discharges of tributaries that have no hydrological information, structural analysis of river network is performed. This approach provides less error in comparison with traditional methods of estimating lateral inflow. The method is used to trace water discharge with increasing distance along the Lena river basin and to evaluate the contribution of geologically and lithologically uneven sub-basins in water discharge formation during a summer low water period.     

Modèles géostatistiques de concentrations ou de débits le long des cours d'eau

Estimating concentrations or flow rates along a stream network requires specific models. Two classes of models, recently proposed in the literature, are generalized, to the intrinsic case in particular. We present a global construction by ‘streams’, i.e. on the whole set of paths between sources and outlet. Combining stationary or intrinsic one-dimensional random functions leads to stationary or intrinsic models on segments, with discontinuities at the forks. A construction from outlet to sources, leads to stationary or intrinsic models on each stream, without any discontinuity at the forks. The linear variogram is found as a particular case. The extension to the linear model of coregionalization is immediate, allowing a multivariate modelling of concentrations. To cite this article: C. de Fouquet, C. Bernard-Michel, C. R. Geoscience 338 (2006).     

基于GIS的山地林道网优化配置系统

应用系统选择永安元沙国有林业采育场的部分林班为示范,建立森林资源空间数据库.以ARC/INFO为开发平台,以山地林道网理论为指导,应用G IS技术、DBMS技术与数学规划集成技术,使用AML语言进行二次开发设计山地林道网优化配置系统,实现计算机辅助林道网配置,提高决策的科学性。     

Statistical analysis for the hydrogeological evaluation of the fracture networks in hard rocks

The hydrogeological effectiveness of fracture sets is determined and evaluated by the fuzzy c-mean and hierarchical clustering. These cluster analyses combine the geological spatial attributes and the hydraulic relevant attributes of fractures. Based on the results of the clustering the fracture set volumes are estimated.     

中国深空测控网建立方案的研究

概述了深空测控网的基本技术要求,总结了我国卫星测控网和国内现有射电观测设施的技术、组成和分布,分析和论述了将我国现有的测控设施建设成深空测控网的具体方案。     

层次化网络SCADA通讯模型及其应用

为在大型网络分布式SCADA（Super Control and Data Acquisition）应用系统中解决诸如电力、通信、石油、化工、制造业等行业或领域，在过程、流程、状态方面的数据监视、数据控制、数据采集与数据管理的高效、实时问题，解决各级子系统之间人工逐级汇接的问题，提高应用系统的稳定性、可维护性，这里提出了一种层次化网络SCADA通讯模型。该模型是通过在层次化网络SCADA模型中，引入基于TCP／IP协议的客户机／服务器查询方式数据通讯技术和点对点主动数据传递技术而建立的。根据该模型所设计的产品，经过生产实践证明，应用该模型可以较方便地构造分布在不同区域计算机上的SCADA系统，进行高效的实时通信。该模型为具有多层结构的大型分布式网络化集中SCADA系统的设计、开发，探索出了一条十分有效的新路径。