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61.
Within the framework of the studies focusing on the Pleistocene peopling of the Americas, our French-Brazilian team has undertaken a pluridisciplinary research on different archaeological sites, inside and in the neighborhood of the Serra da Capivara National Park, in Brazilian Nordeste. The present study regards an archaeological site, Vale da Pedra Furada, situated in the Piauí state in Brazil. The results of technological and functional studies suggest the existence of different successive human occupations during the Pleistocene in this region. Moreover, the geological and geomorphological studies shed new light on our understanding of sedimentary processes and confirm that the levels were not subject to any significant post-depositional processes. This is also confirmed by macro- and micro-analysis of quartz artefact surfaces. The chronological study has recently been completed employing both radiocarbon and luminescence techniques; radiocarbon dates were obtained on charcoal, multi-grain and single-grain OSL ages on sedimentary quartz grains. The results obtained with the different methods are consistent with each other: the most recent archaeological level is dated to around 8 ka and the oldest to 24 ka, indicating the open-air site of Vale da Pedra Furada to be a succession of human occupations beginning from OIS 2. These results are discussed in the context of some archaeological sites studied in the Serra da Capivara National Park of the last few decades.  相似文献   
62.
随着旅游经济的快速发展,传统民居聚落环境正遭受着来自各方面的破坏和压力,这对传统历史文化的传承和弘扬影响深远。如何有效、科学地管理和保护特色鲜明的传统民居聚落这一载体已成为迫切需要解决的问题之一。针对传统民居聚落街巷机理特点,创新性地提出了集成GIS、360°全景影像、移动测图系统(mobile mapping system,MMS)、航空摄影测量、全球导航卫星系统(global navigation satellite system,GNSS)测量和移动物联网等多技术协同的传统民居聚落基础环境数据采集方法和工艺流程,以及基于Geodatabase和Postgre SQL的传统民居聚落特色的多源空间数据存储解决方案,并开发出一套功能完备的传统民居聚落智能化管理系统与移动旅游自助服务系统。实证表明,该系统显著提高了传统民居聚落管理智能化和旅游服务信息化水平。  相似文献   
63.
This paper outlines a methodology to identify informal settlements out of high resolution satellite imagery using the concept of lacunarity. Principal component analysis and line detection algorithms were applied alternatively to obtain a high resolution binary representation of the city of Hyderabad, India and used to calculate lacunarity values over a 60 × 60 m grid. A number of ground truthing areas were used to classify the resulting datasets and to identify lacunarity ranges which are typical for settlement types that combine high density housing and small dwelling size - features characteristic for urban slums in India. It was discovered that the line detection algorithm is advantageous over principal component analysis in providing suitable binary datasets for lacunarity analysis as it is less sensitive to spectral variability within mosaicked imagery. The resulting slum location map constitutes an efficient tool in identifying particularly overcrowded areas of the city and can be used as a reliable source in vulnerability and resilience assessments at a later stage. The proposed methodology allows for rapid analysis and comparison of multi-temporal data and can be applied on many developing urban agglomerations around the world.  相似文献   
64.
社区人居环境吸引力研究——以大连市为例   总被引:2,自引:2,他引:0  
李雪铭  张建丽  杨俊  张力 《地理研究》2012,31(7):1199-1208
城市人居环境研究中一个重要的理论问题就是人居环境吸引力。本文提出人居环境吸引力和引力场的概念,构建了社区人居环境满意度指标体系,运用引力势能模型计算出184个社区的人居环境引力势能,借助MapInfo软件中的Vertical Mapper工具得到大连市人居环境引力势能等值线图和空间分布图,研究表明:(1)运用引力场理论对人居环境评价研究,是一种有效的评价方法;(2)大连市社区人居环境供求关系在空间上形成了"两心一带"分布格局;(3)大连市社区人居环境引力势能空间分异明显,大致呈东北西南向"带状"分布,在中心广场、西安路锦辉商场等值线由同心圆状向外逐渐递减;(4)社区人居环境供求关系与引力势能成正比,与社区与引力势能中心的距离呈反比,城市空间发展结构、海岸带是大连人居环境引力势能空间分布的驱动机制。  相似文献   
65.
The aim of this paper is to explore the relationship between legalization of land tenure and people's capacity to compete for and sustain their stake in the urban land market. Two aspects of land regularization are taken into account: the benefits of land regularization (as collateral for investments); and the perverse aspects of disputes over improved land (due to increased scarcity of illegal, but affordable housing land). Most research on illegal urban land has systematically investigated how to legalize illegal settlements to improve the effectiveness of service provision, whilst attracting public investments. But, few understand the underlying factors motivating people to improve and consolidate their houses where no legal tenure exists. The absence of substantial understanding about people's perceptions of their tenure security has encouraged most research to conclude that improving tenure security leads to higher levels of housing consolidation. What this paper shows is that the relationship between people's perceptions of land tenure security and housing consolidation is much more malleable and complex than conventionally assumed. The subtle difference between tenure of the land and tenure of the house indicates that people are willing to invest in their housing conditions almost irrespectively of their land tenure situation. This finding challenges the orthodox views of the property rights school of thought. In addition, this paper contends that what legalization is really doing is to reduce the available land stock for the poorest families, because legalization decreases the amount of illegal land (illegal land is undesirable, but affordable for the poor). The orthodox legal system needs to be revised to include the poorest families in the urban society of the new millennium.  相似文献   
66.
桩的垂直静载试验极限承载力判定方法综述   总被引:10,自引:0,他引:10  
吕福庆  吴文 《岩土力学》1995,16(4):85-93
桩的垂直静载试验极限承载力(或极限荷载)的确定是试验数据处理的关键。本文汇集编录了极限承载力的各种判定方法,但需指出的是:在具体应用判定试桩的极限承载力时,应以现行规范规定的方法为准,必要时可用其它方法进行校验。  相似文献   
67.
ABSTRACT

The digital transformation taking place in all areas of life has led to a massive increase in digital data – in particular, related to the places where and the ways how we live. To facilitate an exploration of the new opportunities arising from this development the Urban Thematic Exploitation Platform (U-TEP) has been set-up. This enabling instrument represents a virtual environment that combines open access to multi-source data repositories with dedicated data processing, analysis and visualisation functionalities. Moreover, it includes mechanisms for the development and sharing of technology and knowledge. After an introduction of the underlying methodical concept, this paper introduces four selected use cases that were carried out on the basis of U-TEP: two technology-driven applications implemented by users from the remote sensing and software engineering community (generation of cloud-free mosaics, processing of drone data) and two examples related to concrete use scenarios defined by planners and decision makers (data analytics related to global urbanization, monitoring of regional land-use dynamics). The experiences from U-TEP’s pre-operations phase show that the system can effectively support the derivation of new data, facts and empirical evidence that helps scientists and decision-makers to implement improved strategies for sustainable urban development.  相似文献   
68.
乡村聚落地理研究的国外动态与国内趋势   总被引:17,自引:0,他引:17  
本文根据国内外乡村聚落地理研究的内容变化和理论进展,初步划分了乡村聚落地理研究的主要发展阶段。在此基础上,结合国外乡村聚落地理研究的动态及我国乡村地区发展的现实,对我国乡村聚落地理研究进行了回顾与评价,并提出若干重点研究内容与趋势。  相似文献   
69.
中国山区发展研究的态势与主要研究任务   总被引:8,自引:0,他引:8  
陈国阶 《山地学报》2006,24(5):531-538
山区发展问题是一个世界性难题。山区发展滞后是全球普遍的现象。国际上对山区发展研究十分重视,但发达国家与发展中国家因山区发展的水平和方向不同,对其研究的内容也明显差异。我国山区发展既不同于一般发展中国家,也有别于发达国家,正处于受全国工业化、城镇化快速发展冲击的变革期。山区发展在全国总体战略中占有重要地位,但当前是全国区域发展不平衡的主要贡献者,是“三农”问题的集中区和难点区,是全国脱贫的最后攻坚区。国内对山区发展研究虽然已取得巨大进展,但仍不适应新时期对山区发展的需求,加强全国山区发展研究势在必行。当前我国山区发展研究的重点应放在:山区发展战略,建设社会主义新山区,山区工业化,山区农业产业化,山区聚落和山区脱贫等方面上。应以科学发展观统帅山区发展研究,引入现代发展新理念,引进现代科学新理论和新方法,分别在国家层次、区域层次和聚落层次上开展研究;提倡深入山区,深入农村,深入农户;创建山区发展的长期、连续、定点的跟踪调查、监测,构建全国山区发展社会观测网络。  相似文献   
70.
The paper presents a synthesis of French and Bulgarian researches on the transition in villages in Central Eastern Europe. The main points focus on three questions, the rural unemployment and the crisis of small towns, the demographical deterioration, the new relations between villages and towns. A generalization of the rural central places' visual change and metaphors is proposed, completed by a typology of rural settlements. The question of the rural administrative divisions is discussed, with its implication for the future. As a whole the paper gives a contribution to the problematic of the likely development in the rural evolution pattern throughout Europe. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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