地区旅游业应对外部竞争环境的策略组合

该文总结了旅游地空间竞争的层次、形式与影响因素。以其为理论基础,提出地区旅游业可从3方面积极应对外部竞争环境,即合理确定旅游资源开发价值与开发方向、与相邻地区旅游协作和提高地区旅游竞争力,并针对每方面提出了具体的策略和建议。以与天柱山、天堂寨相邻的岳西县为例,分析该县内外风景区之间现实和潜在的空间竞争关系,阐述岳西县旅游业需要采取的竞争策略组合。     

The Topographic Map and Related River Questions of the North China Plain

In the summer of 1917 severe floods inundated the city of Tientsin for several months. As far as one could see from the roofs of high buildings, the plain to the west was a vast expanse of water with numerous islands — villages on mounds — and junks sailing between them, and the sun set in a horizon of water as if it were the ocean itself. For several weeks the Tientsin inhabitants had noticed that the water on the plain stood unusually high, but it used to be inundated more or less every third or fourth summer, so no one cared particularly. The Hai Ho — the Sea River — Tientsin's navigable access to the sea — was high and flowed with an exceptionally strong current through the city. But this was needed to clean out the mud from the river's bottom, and shipping people expected good navigation conditions the next few years.     

芦山地震重灾区地形因子分析

地形条件与山地灾害的发育密切相关,是山地灾害危险性评价的重要因子.以四川省芦山县“4·20”7.0级强烈地震灾区的芦山、宝兴、天全3县为研究区,应用GIS技术计算研究区坡度、地形位指数与地形起伏度,通过流域水文分析方法实现宝兴县子流域划分并提取沟床纵比降,分析灾区地形因子特征,结合灾后崩塌滑坡遥感解译结果,探讨次生山地灾害分布与地形因子的关系.结果表明,研究区坡度大于25°的面积占区域总面积的73.89％,地形位指数大于0.4的区域面积占总面积的85.92％,起伏度大于500 m的占87.41％,各地形因子面积比率最大的区段分别为坡度35°～40°、地形位指数0.648 ～0.666、起伏度500～1 000 m;宝兴县子流域沟床纵比降数值集中于100‰ ～ 300‰范围内.坡度30°～50°的区域为崩塌滑坡的高发地段;崩塌滑坡的优势地形位处于地形位指数0.228～0.246和0.34～0.61之间的区域;起伏度在500～1 000m的区域为崩塌滑坡的集中分布区.研究结果可为灾害评估及灾后恢复重建提供参考依据.     

地形湿度指数算法误差的定量评价

地形湿度指数(TWI)能够定量指示地形对土壤湿度空间分布的控制,是一种应用广泛的地形属性.目前基于栅格DEM的TWI计算方法结果各异,因此有必要对'TWI算法进行定量评价.对TWI算法通常是应用实际DEM数据进行评价.但实际DEM中存在的数据源误差会干扰对算法误差的评价.针对该问题,本文介绍了一种用不含数据源误差的人造...     

JERS-1SAR图像处理及地形信息提取方法研究

本文比较系统地分析了星载合成孔径雷达(SAR)的特点,并利用日本地球资源卫星(JRKS-1)SAK数据进行了去斑点噪声,几何精校正,地形起伏的辐射影响校正,以及边缘增强等处理,并在此基础上进行了地形要素的图像目视解释、区域地貌形态与流域特征的分析等工作。     

Oscillation, Nutation and Wobble of an Elliptical Rotating Earth with Liquid Outer Core

We have constructed a general first-order theory describing those small oscillations of a rotating elliptical earth that are affected by the presence of a liquid outer core. The theory is applicable to free core oscillations and earth tides. Care has been taken to include the effects of the wobble or nutation due to the rotation of the outer core relative to the solid earth. On the basis of the theory the free spheroidal modes of degree 2 and order 1 have been investigated. We have searched for and listed undertones with periods less than 28 hr. No upper limit to the eigenperiods has been detected. It is shown that stable, unstable and neutral polytropic cores are capable of free oscillation. At a period close to the sidereal day the spheroidal mode is accompanied by rigid rotation of the liquid outer core with respect to the solid earth. This is the well-known diurnal wobble of the Earth. It appears probable that the diurnal wobble is one of a class of similar wobbles that involve large toroidal motions in the outer core. Finally, the amplitudes of the 18·6-yr principal nutations has been computed. Excellent agreement is found with observed values.     

Assessing Uncertainty Associated with the Delineation of Geochemical Anomalies

A pedogeochemical exploratory survey of gold deposits was carried out in the region of São Sepé (southernmost Brazil). The region comprises a predominantly metamorphosed belt of volcanoclastics, sediments, serpentinites, basalts, gabbros, chert, tuffs, and banded iron formation of the Proterozoic age. The anomalies were identified first by stream sediment heavy mineral survey at the regional scale of exploration. Once spatial continuity was modeled, ordinary block kriging was performed to generate geochemical maps. Indicator block kriging also was used as an alternative in analyzing and interpreting geochemical data. A novel approach is proposed, which combines both ordinary and indicator kriging for delineating geochemical anomalies. Probability maps proved to be appropriate for selecting new sites for further exploration. Gold anomalies in soils trending NE were well defined by geostatistical analysis and subsequently confirmed by drilling.     

Teaching Topographic Map Skills and Geomorphology Concepts with Google Earth in a One-Computer Classroom

Teaching high-school geomorphological concepts and topographic map reading entails many challenges. This research reports the applicability and effectiveness of Google Earth in teaching topographic map skills and geomorphological concepts, by a single teacher, in a one-computer classroom. Compared to learning via a conventional instructional method, students learning with Google Earth do not have different geomorphological concepts development because both settings enable students to learn with similar static representation. However, students learning with Google Earth improve topographic map skills significantly compared to the conventional instructional method. This is because of the 3D landscape visualization and prior knowledge connections available with Google Earth.