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51.
火山喷发文字记录资料的考证可以给出历史上火山喷发的最为准确的时间限定,对喷发过程、灾害效应也都可给出极为详细、准确的措施。长白山天池火山喷发的满语资料是除了汉语、朝语之处另一种极为重要的资料来源,目前已从有关满语神话传说中得到了若干有重要意义的火山与火山学信息。本文列出了3类、14条天池火山喷发的神话与传说,从中可以得知数千年以来天池火山发生过多次猛烈的与温和的周期性的喷发。天池火山喷发与火山泥石流、喷发后洪水泛滥有密切关系,泛滥物波及到距离天池火山460km以过的嫩江流域及珲春一带。在中国近代史上还有若干次火山喷发记录,经考察较为确定的1951年昆仑山西部于田县卡尔达西火山喷发是一次地下岩浆上侵、地表汽爆炸与喷发的火山喷发事件。 相似文献
52.
基于从业者的旅游历史街区商业空间发展特征及机理——扬州“双东”案例 总被引:2,自引:0,他引:2
旅游商业化是历史街区复兴的重要途径。基于社会空间视角,旅游历史街区商业发展是以从业群体为日常运作核心,兼及居民、游客、恩庇者(管理者)等地域主体在内的空间生产过程。旅游历史街区演化是以“空间实践”为中心环节的社会建构,其发展状态是不同主体、不同层次的空间生产相互博弈的总体涌现。依托扬州“双东”案例,运用田野调查、统计检验、对应分析、模糊数学、逻辑回归等方法,以从业者空间生产为脉络,剖析旅游商业发展机理的杂合性与矛盾性,指出商业空间状态潜伏着不对称的利益博弈和不均衡的发展效应。“双东”旅游商业开发对城市中低产阶层自主就业有较强吸附效应,使之成为商业发展的主要依托。从业群体大致分化为乐观型、寓居型、保守型,分别对应于积极评价—业务扩张、温和评价—业务维持、消极评价—业务收缩生产机理,对“双东”空间演化具有不同的响应机制和影响效应。研究分析了主体、实践、环境特质对不同类型从业个体的影响特征以及对从业群体的总体影响,认为恩庇是统摄“好恶效应”、操控利益格局的多解方案。旅游历史街区商业发展利弊兼具、相因相生,统一于历史街区的自我演替过程。 相似文献
53.
The postwar urban renewal experience varied among US cities according to the result of local social contests pitting those imposing their power to transform urban space against those resisting it. In this paper, we examine the role of one such contest in shaping urban renewal outcomes in Denver, using the case of the late 1960s Auraria project. The project sought to remove a poor, Hispanic neighborhood in order to build a new downtown college campus, generating community opposition from the inner city neighborhood residents, leaders of the city’s Chicano Movement, and historic preservation activists. We demonstrate how resistance actively shaped the ultimate form and character of the project, and how the legacies of this urban renewal contest extended—in unforeseen ways—beyond the immediate struggles of the time. We argue that these legacies provide the essential context for understanding planning practice, redevelopment strategies, and gentrification dynamics in the city today. 相似文献
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Problems of sustainable development in connection with the change of biogeochemical cycle of selenium and overcoming its deficiency in Russia, Serbia, Belarus and other countries are reported. The history of the biological role of selenium as an essential trace element is discussed. A special program of «Overcoming of selenium deficiency» has been developed by researches of Russia, Serbia and Belarus in view of high morbidity rates for cardiovascular, tumor and endemic diseases affecting the population of both the above and some other countries, including children, prevalence of selenium deficiency among livestock species and aggravation of the environmental situation as a result of man-made processes. 相似文献
57.
Dona J. Stewart 《The Professional geographer》2001,53(3):361-373
This article presents a methodology for a more detailed investigation of urban landscape change in rapidly growing cities of the less developed world beyond typical macrolevel approaches. This research is an attempt to bridge the gap between traditional landscape analysis and geographic information science (GIS). The article presents the preliminary results from a pilot project in Zamalek, Egypt, highlighting the benefits and drawbacks of the two techniques. Rarely used to study the less developed world, these techniques are utilized to assess change within a portion of Cairo's urban landscape. Large‐scale historic maps and high‐resolution satellite imagery, combined with field attribute collection, are the major data sources in this applied landscape analysis. A motivating factor in the desire to examine landscape change at such a large scale is the need to create monitoring systems for historic preservation in cities of the less developed world. 相似文献
58.
Relationships of Louisiana Colonial Land Claims with Potential Natural Vegetation and Historic Standing Structures: A GIS Approach* 总被引:1,自引:0,他引:1
Peter B. Mires 《The Professional geographer》1993,45(3):342-350
Louisiana's French, Spanish, and British colonial administrations left a vivid imprint on the landscape in the form of unique cadastral survey systems. The collective distribution of these colonial land claims presents a picture of the colonial occupation of the state. Settlement shows up clearly along the waterways of the bayou state. Equally significant are the areas devoid of land claims. This paper discusses the compilation of the colonial Louisiana land claims map and demonstrates its utility to GIS-based historical geography and historic preservation. By merging this map with other digitized datasets such as potential natural vegetation and historic structures, the seemingly chaotic 18th century occupance of an extremely heterogeneous physical environment becomes patterned, and prior assumptions about the colonial settlement process may be tested with greater precision. 相似文献
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基于空间语义角色的自然语言空间概念提取 总被引:4,自引:1,他引:4
根据空间信息的特点,从定义的空间语义角色入手,通过语义角色标注、短语识别以及概念模式匹配等手段,具体分析了自然语言中的空间实体、实体间空间关系以及空间过程的表达与提取方法。 相似文献