桂林乡村旅游信息资源开发与利用研究

分析了桂林乡村旅游信息资源建设的现状,探讨了桂林乡村旅游信息资源开发与利用问题,分析了桂林乡村旅游产品采取C2C网络交易模式的可行性。     

多变量系统模糊动态模型的辨识

介绍了一种新型的基于模糊神经网络的多变量模糊动态模型的辨识方法 ,该方法是通过将输入空间进行直接划分 ,而不是在输入空间的每一维上进行划分来得到模糊规则的。这样所形成的隶属函数为多维隶属函数 ,并使模糊规则的数目大为减少。在模糊聚类算法的基础上 ,提出了一个衡量聚类有效性的函数 ,以确定模糊规则的数目。以二级倒立摆系统为应用背景 ,取得了较好的辨识效果。     

赤水桫椤自然保护区植物和植被多样性现状及特点分析

通过分析赤水桫椤自然保护区内植物物种多样性、特有种、植物区系、具有重要保护意义的物种以及其他特色的保护对象,指出赤水桫椤自然保护区植物物种丰富多样,是重要古老木本蕨类桫椤的重要种源库。同时物种和生境的多样性,使得植物群落类型也表现出一定程度的多样性。根据群落发生的不同以及“植物群落学———生态学原则”的划分标准,将该保护区自然植被划分为 5个植被型,人工植被划分为 6种类型,并分别进行了分析。     

Effect of ciliary neurotrophic factor on the reactive astrogliosis of cultured astrocytes from newborn rat brain

The effect of ciliary neurotrophic factor (CNTF) on reactive astrogliosis was studied on a mechanical scratch model of the confluent astrocytic cultures from newborn rat brain. Following injury, the astrocytes at the edge of the injured area displayed a typical process of the reactive astrogliosis. This process included apparently hyperplastic change and significantly increased GFAP expression of the flat astrocytes, and migration to the injured area of the O-2A progenitor cells and their differentiation into process-bearing astrocytes. Exogenous CNTF applied to the cell cultures significantly promoted the hyperplasia and GFAP expression of the flat astrocytes. The results suggest that CNTF can enhance the reactive astrogliosis in the injured area.     

基于有限元分析的页岩气扩散数值模拟

本文基于Fick扩散定律,结合页岩气赋存形式和运移特点,针对干酪根有机质中溶解气扩散形式,建立干酪根中页岩气扩散数学模型。利用有限元分析方法进行数值求解,得到不同时刻干酪根内部页岩气浓度分布,分析干酪根内部不同位置浓度变化规律,内边界气体平均扩散通量变化规律,并通过计算得出给定符合页岩储层有机干酪根存在条件下干酪根扩散通量。同时在该扩散模型基础上改变边界条件,可以理论上计算多孔介质中气体有效扩散系数,为今后关于页岩气渗流理论和数值模拟研究奠定了基础。     

基础地下室混凝土施工的体会

文章结合实际工程的监督情况,对地下室砼工程施工中容易出现的问题作了一些简要的分析。     

在多跳跃-扩散过程下的幂型再装期权的定价

考虑股票价格服从多跳跃随机过程,在无套利的条件下,通过运用等价鞅测度的方法和条件期望的一些结论,推导出在多跳跃-扩散过程下幂型再装期权的显式解.     

基于单偏馈抛物面天线空域极化特性的最佳波束宽度研究

先给出偏馈抛物面天线远场的主极化和交叉极化分量的理论推导,得出其空域极化特性是焦径比和偏馈角的函数。根据实际单偏馈抛物面天线设计中的约束合理设定了天线模型的参数,然后利用专业软件对天线的空域极化特性进行了仿真分析。从大量仿真实验结果中总结了单偏馈抛物面反射天线空域极化特性随着方位角、俯仰角、偏馈角、焦径比改变的变化规律,在此基础上提出了天线空域极化特性处理的最佳波束宽度的概念并给出天线空域极化特性在最佳波束宽度内的变化规律。     

Utilizing Chinese high-resolution satellite images for inspection of unauthorized constructions in Beijing

After Beijing wins the bit to host the 29th Olympic Games, in order to manifest the technical support advantages and capabilities of the autonomously-developed RS and GIS based change detection techniques in 2008 Beijing Olympic Games, and from the standpoints of executing new city planning, relieving the traffic congestion as well as maintaining the historic features, an automatic satellite monitoring system has been studied and established to accomplish the mission of unauthorized construction inspection within the Sixth Ring Road of Beijing city quarterly, by adopting the CBERS-2 satellite images and combining technologies of GIS, GPS, etc. This article discusses the applicable procedures and key issues when utilizing such Chinese satellite images and relevant techniques to discover the illegal constructions, and introduces the monitoring system from both the design and implementation aspects; additionally, some typical application cases in the practice of the system are also illustrated. The monitoring system can timely supply abundant information to facilitate the policy-making of relevant planning departments, thus providing consolidate technical support to eliminate the illegal constructing behaviors in the blossom. During the five years＇ excellent performance, it has helped China save large amounts of expenditures for processing of unauthorized constructed buildings.     

Effects of three coupling coefficients on the spectrum characteristics of superstructure fiber grating

For the superstructure fiber grating (SFG) consisting of fiber Bragg grating (FBG) and long-period fiber grating (LPFG), there exist three kinds of coupling: the contra-directional coupling between forward propagating core mode and backward propagating core mode, the contra-directional coupling between core mode and cladding mode, and the co-directional coupling between core mode and cladding mode. By using the similarity transformation method for the coupled mode equations, the effects of three coupling coefficients κ _co L, κ _cl L, and κ _S L on the transmission and reflection spectra of SFG have been investigated. The simulations show that the overall intensity of the transmission spectrum of SFG is decided by LPFG, that the main lobes of the transmission and reflectivity spectra of SFG are decided by coupling coefficients κ _co L an κ _S L, and that the side lobes of the transmission and reflectivity spectra are decided by coupling coefficients κ _cl L and κ _S L. Biography: YUAN Yinquan (1964–), male, Professor, Ph.D., research direction: fiber optical sensors.