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31.
The quick and accurate identification of post-earthquake rescue objects can minimize the casualties and property loss caused by earthquakes. With the rapid development of remote sensing technology, rescue objects can be identified through high-resolution remote sensing images. There are two main categories of approaches to identify rescue object through high-resolution images: automatic extraction by a computer and visual judgment by professionals. Although results can be obtained quickly by using automatic extraction, the accuracy of the results is unacceptably low. For visual judgment, the large demands for time and professionals restrict its wide practical application. In this study, we introduce crowdsourcing into the identification of post-earthquake rescue objects. First, we integrate the advantages of the computer and crowdsourcing, which means that the computer takes advantage of the speed of information processing, while crowdsourcing makes full use of human recognition capabilities. Second, we take visual judgment tasks out of the hands of professionals and entrust the tasks to workers in a crowdsourcing platform. Not only are the human resources infinite, but we can also improve the efficiency of identifying rescue objects. Third, we propose a crowdsourcing model that improves the quality of the results and saves human resources. Finally, experimental results demonstrate that our solution is feasible. 相似文献
32.
Chien-Min Chen 《Tourism Geographies》2019,21(1):78-101
ABSTRACTTo assess tourist motivations at the battlefield site on Kinmen Island of Taiwan, an empirical investigation was conducted. From a convenience sample, we collected 437 effective responses of respondents including domestic and international tourists with different cultural background in Kinmen. The structure of motivation was first examined via factor analysis. Then ANOVA analysis was applied to address the influence from demographic aspects such as gender, age, and nationality. Our results show that personal, spiritual, experience, physical, and emotional perspectives are five major sources of motivations. More importantly, age and nationality are confirmed to be two major dimensions to segment tourists in the context of battlefield tourism. Tourists with older age have higher motivations toward the battlefield site in comparison with young tourists. In addition, tourists with different cultural background based on different nationalities are significantly motivated by various motivational factors. The example of Kinmen contributes theoretically to a better understanding of the motivational attributes in a battlefield site, and how they represent a basis for increasing tourist perceptions. The motivational mechanisms and factors explored in this case can be incorporated into marketing strategies. Additionally, our results also provide a viable basis for the tourism authorities concerned to reevaluate the essence of its tourism industry in the context of battlefield resources and attractions. 相似文献
33.
Francisco Sergio Campos-Sánchez Francisco Javier Abarca-Álvarez Rafael Reinoso-Bellido 《European Planning Studies》2019,27(7):1270-1290
The benefits of urban open spaces for improving the quality of life and sustainability in cities are widely recognized. The functions they perform within the framework established by urban planning, as well as their metrics, are now more complex than in the past. It is convenient to develop methodologies for the evaluation of these spaces adapted to the present time to check their level of efficiency, which is useful in urban planning for the establishment of new urban open spaces. The aim of this study is to classify such spaces through a methodology that integrates spatial analysis, configuration analysis, and decision support so as to understand their complexity from a more advanced analytical perspective. In order to do this, a prior exploration of specific literature is carried out, which allows the characterization of the functions of urban open spaces by means of the corresponding analysis variables in a weighted manner. The integrated combination of these advanced tools is a step forward in achieving consistent and detailed results for urban open spaces. They perform their functions best in dense, central, equipped, accessible, connected, and easily walkable urban environments. In addition, future recommendations are provided. 相似文献
34.
Véronique Favre-Bonte Elodie Gardet Catherine Thevenard-Puthod 《European Planning Studies》2019,27(5):1035-1057
As there is little research on the link between territories and interorganisational networks, this paper examines how the nature of a territory influences the characteristics of innovation networks. It compares the innovation network forms of two types of territories (high-altitude and medium-altitude mountain resorts) regarding four characteristics of networks widely debated in the literature: the nature of the relationships between members, the mode of regulation used, the architecture, and the geographical proximity of members. This research makes a significant contribution to both the spatial development and innovation management literature: indeed, our results show that according to the nature of the territory, innovation networks differ in terms of partners, geographical proximity, and regulation mode. However, the nature of the territory does not seem to influence the architecture of the innovation network since those networks need a hub organization that orchestrates the partners’ actions. These results, by providing a better understanding of the characteristics of innovation networks, help tourist territories to better attract customers. 相似文献
35.
中国城市群空间结构演化的影响因素分析——基于铁路客运的功能联系视角 总被引:1,自引:0,他引:1
以中国13个城市群为研究对象,采用铁路客运班次构造多中心指数来表征基于功能联系的城市群空间结构,在分析城市群空间结构演变基础上重点分析其影响因素。研究发现,基于功能联系视角的城市群空间结构总体呈单中心化趋势,但地区差异化明显,珠三角、山东半岛和闽东南城市群已表现出多中心化特征;城市群空间结构的多中心程度随经济发展水平的提高表现为先单中心后多中心的演变过程;城市群规模的增大和城市间联系加强促进了城市群向多中心方向演化;而面积小、三产比重高的城市群更有利于形成单中心的结构;政府干预作用对城市群空间结构影响并不显著。鉴于不同城市群空间结构演化趋势不同,未来政策取向应该遵从各个城市群自身规律。 相似文献
36.
借助可视化软件,从梳理研究热点及识别研究主题两方面,厘清世界城市网络的研究脉络与核心,探索未来研究动向。研究发现:①世界城市网络研究国际合作广泛,研究热点响应迅速,经历“世界城市”与“世界体系”分化阶段,网络结构聚焦阶段,城市网络的空间、地位、经济等多元阶段变迁;②研究由城市网络链接结构、全球中心城市、城市网络节点地位及城市网络经济学四大主题构成;③以往研究缺乏对网络结构绩效的研究,对非世界城市的关注不够,城市地位与经济之间的关系仍处于描述阶段;④对世界城市网络结构的内涵、非世界城市研究、整体网络与个体网络关系、经济学方向进行展望,使世界城市网络的未来研究更加全面丰富。 相似文献
37.
Is urbanization good for the environment? This paper establishes a simple core–periphery model with monocentric cities, which comprises key forces that shape the structure and interrelation of cities to study the impact of the urban evolution on the environment. We focus on global warming and the potential of unfettered market forces to economize on emissions. The model parameters are chosen to match the dichotomy between average “large” and “small” cities in the urban geography of the United States, and the sectoral greenhouse gas emissions recorded for the United States. Based on numerical analyzes we find that a forced switch to a system with equally sized cities reduces total emissions. Second, any city driver which pronounces the asymmetry between the core and the periphery drives up emissions in the total city system, too, and the endogenous adjustment of the urban system accounts for the bulk of the change in emissions. Third, none of the city drivers gives rise to an urban environmental Kuznets curve according to our numerical simulations. Finally, the welfare‐maximizing allocation tends to involve dispersion of cities and the more so the higher is the marginal damage from pollution. 相似文献
38.
Martina Heßler 《Berichte zur Wissenschaftsgeschichte》2007,30(2):145-160
Science Cities: What the Concept of the Creative City Means for Knowledge Production. – The article aims to show that the relationship of science and the city has changed since the 1970s in the context of the knowledgeable society. While cities have principally been regarded as the typical space of science, of new ideas and innovation for centuries, since the 1960s and 1970s universities, research institutes as well as industrial research institutes have relocated to the periphery of cities. There, however, these sites of knowledge have been organized in an ‘urban mode’. That means that the concept of the city as a place of science and innovation has determined the architectural, spatial, and social organization of these sites on the periphery of cities. Certain features of the city have been copied, such as social infrastructures, places of communication, restaurants, cafes etc., while others have been left out – housing, cinema, theatre etc. An ‘urban mode of knowledge production’ in the sense of a very stylized model of the city has become a tool to enhance the production of scientific and technological knowledge. – The article exemplifies this by focusing on a case study, namely of the so‐called ‘Science City’ of the Siemens Company in Munich‐Neuperlach. 相似文献
39.
扎什琍玛佛像因特征明确、像式丰富、工艺精细,在故宫珍藏的佛教造像中独树一帜。清宫的扎什琍玛像多附有皇家特有的黄条题记。本文从这些黄条所记内容入手,结合档案资料,对此类造像进行来源、类型及题材风格的细化探究,并进一步说明扎什琍玛对清宫佛教造像风格的深刻影响及其在促进西藏与内地政治、经济、文化联系方面曾经发挥的历史作用。 相似文献
40.
Annett Steinführer Annegret Haase 《Geografiska annaler. Series B, Human geography》2007,89(2):183-195
Contemporary cities in East Central Europe (ECE) represent a hybrid type of urban development which is still generally considered to be a special case and is only exceptionally referred to in the recently intensified debate over the European city. Our paper argues that such exclusion is short‐sighted because ECE cities face structural problems similar to those of their Western pendants. Therefore, the contextual frame of urban research needs to be widened and can no longer be restricted to post‐socialist transition. In this regard, one of the main challenges for future urban development will be the consequences of demographic change. Ageing, new patterns of fertility behaviour and more diversified household structures in line with the Second Demographic Transition (SDT) will have significant implications for urban structures and housing markets, as already known for Western Europe. The purpose of this paper is to work out new questions and hypotheses for future urban research with special respect to Polish and Czech cities. Besides West European experience, recent developments in eastern Germany are taken as a frame of reference, assuming that this specific transition case may, in many respects, be regarded as a forerunner for similar developments in its neighbouring countries. 相似文献