基于行政隶属关系树状图的地名消歧方法

同一地名映射不同物理空间位置的地名歧义现象普遍存在,地名消歧是指为地名分配唯一地理位置的过程.欧美国家的地名数据库和相关知识库比较完善,提出一系列通用或适宜个别语种的地名消歧方法.由于我国当前缺乏类似的高质量数据资源,难以直接引入这些方法解决中文地名消歧问题.该文提出在地名识别和地名匹配的基础上,通过构建歧义地名行政隶属关系树状图,利用上下文相关地名在树状图中出现的子节点数,判断歧义地名指向的地理位置.实验表明,该方法简单易行,而且可以达到较好的消歧效果.     

Use of Business-Naming Practices to Delineate Vernacular Regions: A Michigan Example

This article provides a history of efforts to map vernacular regions as context for offering readers a way of using business directories in order to construct a GIS-based map of vernacular regions. With Michigan as a case study, the article discusses regional-naming conventions, boundaries, and inclusions and omissions of areas from regional labels in order to offer educators ideas that can enhance classroom content on regions. This article concludes by providing suggestions for classroom activities collecting, analyzing, and discussing vernacular region patterns and processes in accordance with National Geography Standard Five at the eighth-grade level.     

STRATIFIED MARINE LAKES OF PALAU (WESTERN CAROLINE ISLANDS)

The physical geography of the limestone islands of Palau permits permanent water-column stratification in 13 tropical sea-level marine lakes, each with unique water-column physics, chemistry, and biology. Embayments and lagoons amid the coral became isolated as marine lakes after Miocene uplifting. Surface mixing of lake water by wind is reduced by jungle-covered karst ridges. Surface tidal exchange through fissures in fenestrated karst is slow while midwater exchange through submarine tunnels is fast, but both produce damped, delayed tides with modest seawater exchange from the barrier-reef lagoon. Topographic protection from wind, heavy regular rain throughout the year, with precipitation exceeding evaporation, and modest tidal exchange produce stratified water columns with brackish waters above permanently anoxic saline hypolimnia. Permanent lake stratification is documented for 18 years; sediment cores (by others) show stratification for >100 years, and recent constant sea level implies ecosystem stability for thousands of years. Therefore, the marine lakes in Palau are small, closed, simple ecosystems that do not change over time–steady-state chemostats permitting replicate field measurements of biological and physical attributes from day to day, month to month, or decade to decade. [Key words: Palau, meromictic, marine lake, karst, lake stratification, tides, model ecosystem.]     

Wavelet triangulated irregular networks

GIS applications have recently begun to emerge on the Internet. The management of three-dimensional geographic datasets in this distributed environment poses a particularly challenging problem, which highlights the need for a good data representation. This paper presents a new multiresolution data representation: the Wavelet Triangulated Irregular Network (WTIN). Compared to the traditional cell-based Digital Elevation Model (DEM) format and the Triangulated Irregular Network (TIN) format, it is more compact and suitable for scalable distributed GIS services. This format is based on the second-generation wavelet theory and is specially designed for geographical height field data. The modified Butterfly scheme is used for constructing the wavelet transform. For every point in the geographic surface, only a single wavelet coefficient is used, which makes the final data representation very efficient and easy to compress. Because the transform used in the data representation is a linear filter operation, the computational efficiency is better than other multiresolution data formats for terrain surfaces. Results from numerical experiments on real data are given to demonstrate that the proposed data representation can be efficiently implemented. The results show that the proposed WTIN data format can provide multiresolution data sets, which achieve significant compression while preserving geographical features. The quality is found to be quite acceptable for geographical terrain representation.     

区域旅游产业集聚与绩效的关系研究——基于中国31个省区的实证

利用Gini系数、E-G指数、行业地区集中度等产业集聚指标以及产业利润率、就业系数、劳动生产率等产业绩效衡量指标,基于2010年的截面数据,探究中国旅游产业集聚化发展及其与产业绩效之间的关系。结果表明:整体旅游产业的集聚程度较低,但产业内部各行业的区域集聚特征明显;旅游产业集聚程度的区域差异与区位条件差异具有较高的一致性;旅游产业集聚总体上对产业绩效的提高具有积极影响,其中,旅游产业集聚对产业利润率和劳动生产率的提高有显著的正向影响,但是对于就业机会的增加影响甚微。基于上述结论,提出相关政策建议。     

Politics,Public Space,and Memorials: The Brawl on the Mall

This paper examines recent proposals for memorials and monuments on the National Mall in Washington, DC. Demands for memorials are increasingly at odds with the Mall's important role as open green space and public protest space. This article analyzes the broader issues embodied in the competing purposes of this highly visible public space by considering the recent controversy over the World War II Memorial. The controversy focused primarily on the location of the memorial. Opponents contended the World War II Memorial would interrupt or destroy the iconography of the National Mall. Supporters argued that the location selected for the memorial was consistent with its importance in U.S. history and that it deserved such a prized location in the central axis between the Lincoln Memorial and the Washington Monument. The article then analyzes the politics behind the site selection, and examines the debate about the impact of the memorial's location. It concludes that the location of the memorial was not accidental but intentional, and thereby reveals a purposeful re-writing of the Mall's symbolic space to suit a specific vision of the war and its meaning in American history. The article also contends that the location of the memorial represents an emerging social-political agenda that is prioritizing the Mall as a place of commemoration at the expense of open space, and, perhaps, at the expense of public protest space.     

北京城郊山地森林游憩机会谱构建

20世纪中叶,到森林中休闲游憩的人数剧增,为了保护生态环境,同时为游客提供高质量的游憩体验,美国林务局的管理者和专家发展了游憩机会谱(ROS)理念和管理框架,其主要以游憩需求为导向,依据"自然环境"、"社会环境"和"管理环境"指标对游憩区进行分类分级,编制游憩机会清单,对资源进行清查、规划和管理。本文在介绍ROS理论的基础上,结合北京市民森林游憩的需求特征和森林游憩区当前的管理体制和开发利用现状,筛选出"自然程度"、"偏远程度"、"游客密度"和"管理强度"4个评价指标,分析提出了北京山地森林游憩机会谱,将北京城郊山地森林游憩区分为城郊开发区域、城郊自然区域、乡村开发区域、乡村自然区域和半原始区域五个游憩机会等级,并结合目前的北京市游憩资源的利用和管理现状,用GIS作图直观展示了各游憩机会的分布,分析比较了各游憩机会的供需状况,为北京城郊森林游憩的规划和管理提出了合理化建议。     

卫星遥感结合气象资料计算的中国干旱区夏季地面感热特征

选用美国国家海洋和大气局(NOAA)系列卫星观测的1982-2006年历年夏季每半月合成的归一化差值植被指数(NDVI)数据资料和针对我国西北干旱区不同下垫面的Ch-INDV参数化关系式,计算了我国110°E以西/35°N以北区域内84个气象站历年夏季各月的地表热力输送系数Ch值和地面感热通量序列,并将其与ERA-40再分析感热资料进行了比较分析。随后,通过数理统计和经验正交函数(EOF)分析方法,研究其时空分布的基本特征和异常变化的演变规律及其东、西部地面感热年际变化的差异。主要结论为:(1)我国西北干旱区夏季地面感热通量实际计算值与ERA-40再分析感热资料相比,两者在值的大小、分布形势和年际变化趋势上均较一致,但感热实际计算值的空间分布更加明显地突出了各气象站所在区域的局地特征。(2)对西北干旱区夏季地面感热EOF分析表明,第一模态反映了全场一致的空间变化,第二和第三模态在干旱区东部和西部区具有不同的南北反向或东西反向的空间变化。第一和第二主分量有较明显的年代际或更长时间尺度的周期变化,第三主分量的年际变化较明显。(3)西北干旱区东部和西部夏季地面感热输送具有相反的年际变化趋势,干旱区东部呈逐年增加的趋...     

内蒙古农牧交错带生态补偿效应分析

中国的生态补偿实施主要通过制度安排进行。在内蒙古农牧交错带,生态补偿主要通过两种模式进行,即对农牧户放弃土地使用和生产结构调整给予补偿。基于详尽的野外调查,本研究对农牧户经济受偿意愿进行了对比分析,并对两种生态补偿模式的效应进行了详细评价。结果表明,放弃土地使用的生态补偿模式缺乏创造就业机会的机制,因此不具有可持续性。与此相反,调整生产结构的补偿方式不但使农户从事农牧业的规模有了明显下降,而且有助于创造更多的就业机会。虽然这种模式会使农户面临很大的市场风险,但是它为解决区域生态系统恢复和社会经济发展之间的矛盾提供了一种有效方法。     

基于遥感和GIS的黄土高原中阳县土壤侵蚀评价

黄土高原地区是我国水土流失最严重的地区,定量评价土壤侵蚀量、土壤侵蚀强度及其空间分布特征,可以为水土流失防治措施的制定提供依据.基于遥感和GIS,应用修正的通用土壤流失方程(RUSLE)对山西中阳县土壤侵蚀进行评价.结果表明,中阳县平均土壤侵蚀模数为2 874.25t/(km2·a),属于中度侵蚀地区,年平均土壤侵蚀量408.78×104 t.发生中度以上土壤侵蚀面积占总面积的29.95％,土壤侵蚀量占总侵蚀量的85.61％,这部分土地是土壤侵蚀防治的主要区域.黄土区发生轻度以上土壤侵蚀面积大,所占比例多,侵蚀程度严重.微度土壤侵蚀面积以有林地为主,轻度和中度土壤侵蚀面积主要是未成林造林地和灌木林地,发生强烈以上土壤侵蚀面积主要是疏林地、未利用地、灌木林地和农田,土地类型、植被覆盖与土壤侵蚀有着密切关系,林业生态工程建设对于中阳县控制水土流失和改善生态环境有着重要作用.