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1.
Over the last two decades, online communities have become ubiquitous, with millions of people accessing collaborative project websites every day. Among them, the OpenStreetMap project (OSM) has been very successful in collecting/offering volunteered geographic information (VGI). Very different behaviours are observed among OSM participants, which translate into large differences of lifespan, contribution levels (e.g. Nielsen’s 90–9-1 rule) and attitudes towards innovations (e.g. Diffusion of innovation theory or DoIT). So far, the literature has defined phases in the life cycle of contributors only based on the nature of their contributions (e.g. role of participants and edits characteristics). Our study identifies the different phases of their life cycle from a temporal perspective and assesses how these phases relate to the volume and the frequency of the contributions from participants. Survival analyses were performed using both a complementary cumulative distribution function and a Kaplan-Meier estimator to plot survival and hazard curves. The analyses were broken down according to Nielsen and DoIT contributors’ categories to highlight potential explanatory variables. This paper shows that two contribution processes combine with three major participation stages to form six phases in contributors’ life cycle. The volume of edits provided on each active day is driven by the two contribution processes, illustrating the evolution of contributors’ motivation over time. Since contributors’ lifespan is a universal metric, our results may also apply to other collaborative online communities.  相似文献   

2.
杨水根  王露 《地理科学》2020,40(11):1909-1920
运用协同度模型、空间ESDA、趋势面分析和面板计量回归模型,分析湖南省武陵山片区2001—2017年人口城镇化与流通产业发展协同的时空演化特征及其减贫效应。研究发现:湖南省武陵山片区人口城镇化与流通产业协同发展整体呈上升趋势但水平偏低,不同板块间协同水平差异显著且有扩大倾向;具有“集聚–分散–集聚”空间循环过程,局部空间极化效应明显,形成邵阳板块的显著热点区和湘西自治州板块的显著冷点区;协同发展“东高西低”空间分布格局更趋明显,“北高南低”分布态势减弱;两者协同发展对农民收入提升、贫困减缓具有显著正向促进作用,进一步空间效应分解发现协同减贫的空间正外溢性显著;实施人口城镇化与流通产业发展“双轮”协同驱动战略是实现乡村振兴的现实需要,也是落实高质量脱贫方略的重要支撑。  相似文献   

3.
孙宇婷  肖凡  周勇  田广增 《热带地理》2020,40(3):375-385
公众关注作为疫情防控与舆情治理的重要环节,其时空差异与影响因素却鲜见被讨论。因此,文章将百度搜索指数作为网络公众关注度的测量指标,采用百度人口流动大数据和疫情实时监测数据,运用空间分析、时空可视化、回归分析等方法,分析2020-01-09—03-02中国公众对“新型冠状病毒”网络关注度的省域时空差异与影响因素。研究发现:1)在空间上,公众对疫情的关注度东、西部差异较大,沿海高于内陆,且与疫情高发区吻合;在时间上,武汉“封城”前后各省份的公众关注度分布格局基本趋于一致,且“封城”后均明显高于“封城”前;春节期间关注度达到最高峰,而后随疫情周期性规律(潜伏—暴发)呈波动式下降;关注主题遵循“从早期对相关病毒的搜索到后期关注临床诊断与发展状况”的疫情发展规律。2)疫情动态数据、武汉人口流动的日动态因素与固定区位特征的经济社会发展因素会不同程度地影响受众对疫情的关注度,当疫情基本得到控制,宏观区位因素对公众关注度的影响作用开始凸显,具有持续稳定的影响;3)影响因素在疫情暴发前后2个阶段对公众关注度起着不同的影响效果。在疫情暴发初期,公众更易受疫情动态信息影响引发主动搜索行为;而在疫情暴发后期阶段,公众将注意力转移到流入各省份的武汉人口上。  相似文献   

4.
随着开源网络地图服务Open Street Map(OSM)数据精度的提高和数据覆盖范围的扩大,其应用已逐渐渗透到各个领域,国内外专家学者对OSM的研究也不断地深入。为探究OSM在极地科考领域的应用实现,同时促进我国极地信息化事业的快速发展,从应用角度出发,论证了OSM在补充谷歌地图实现"雪龙在线"网络信息平台功能的可行性。实现了本地OSM全球地图数据库的建设,并在实现极地网络地图服务(WMS)功能基础之上提出多源空间数据的融合与可视化表达的技术路线,为极地海冰检测与动态变化研究提供了有利的支持,为极地主管部门决策的制定与实施提供了可靠的保障。  相似文献   

5.
发展地理学视角下欠发达地区贫困的地方分异与治理   总被引:5,自引:1,他引:4  
刘小鹏  李伟华  王鹏  王亚娟  程静  马存霞 《地理学报》2019,74(10):2108-2122
在梳理发展地理学的发展过程、基本理论、分析模式和方法的基础上,结合中国解决区域性整体贫困目标和可持续发展本地化与减贫的学术探索,构建了欠发达地区贫困的发展地理学分析框架,建立了由经济地理资本、社会地理资本、文化地理资本、生态地理资本和政治地理资本构成的“五位一体”地理资本指标体系,提出了数据处理集成方法和技术流程,系统分析欠发达地区贫困的地方分异与治理方案。实证研究显示:① 地理探测可以确定作用地方贫困的主导地理资本,各主导地理资本对贫困发生率的决定力LA, P ≥ 0.15;② 在不同主导地理资本作用下,5个单维地理资本指数及其合成的区域地理资本指数地方分异明显,存在阻隔和时滞特征;③ 贫困的地方分异可分为经济地理资本约束型、经济—社会地理资本约束型、经济—社会—生态地理资本约束型、经济—社会—文化—生态地理资本约束型4大类共7小类;④ 立足发展特征,挖掘地方动力,提出不同贫困分异类型的地方治理对策和模式。乡村振兴和2020年的减贫转向,应重视欠发达地区贫困的空间分异与空间扩散、空间整合的综合研究,为可持续发展本地化与减贫提供发展地理学解决方案。  相似文献   

6.
This article discusses the use of geographic information technologies to assist researchers in the exploration of historical databases. The case study is a pilot project in which we used geographic information systems (GIS) and global positioning systems (GPS) to study the history of the Public Waterfront Act (the “Chapter 91” program), a policy designed to balance private property rights, public interest, and environmental protection in the Massachusetts tidelands. The issues discussed range from the role of GIS in society and its limitations as a representational tool to the ability of current GIS to deal with historical data and to manage temporal attributes.  相似文献   

7.
基于广州市居民食品购物行为问卷调查数据,利用交叉频数、卡方检验和对应分析,通过网购食品者同不网购食品者、不同区位网购食品者、不同网购食品频率者的对比,分析了网络购物影响下广州市居民购买食品行为的一般特征和空间特征。结果发现:1)网络购买食品的接受度总体不高,传统实体购物模式仍占主导,网络购买食品对实体店购买食品有一定的替代沁。2)网络购买食品对居住地周边商店负面影响较大,对商业区影响很小,超市和百货公司休闲零食、地方特产类食品销售会受到一定负面影响,生鲜类商店所受影响较小。3)不同区位居民网购食品的频率差异较小,单次花费、时间和网购原因空间差异较大,实体购物条件差的居民更倾向于网络购买食品,验证了Anderson等提出的“效率假说”。4)网购食品者的实体购物出行目的休闲性增加,周末购物出行更频繁,网购食品频率高的居民购物出行时间更短。  相似文献   

8.
Wilbur Zelinsky's 1971 paper in Geographical Review entitled the “Hypothesis of the Mobility Transition” was both forward‐looking and offered innovative ideas regarding human geographic mobility. One of the most interesting aspects of the paper was a set of predictions for mobility in a “future superadvanced society”. Many of these predictions have now come to pass, including a general decline in international and internal migration and residential change, the increasing regulation of migration ‐ especially internally, and the possibility that the widespread adoption of information and communication technologies has impacted human geographic mobility. Hence, this essay looks at the mobility transition not as an obsolete frame of reference but as a prescient, pliable, and adaptable framework which not only informs the study of human geographic mobility today but also, perhaps, even into the future.  相似文献   

9.
Geospatial data and tools are key in locating lost or missing persons in as short a time as possible. In this study, we used a geographic information system (GIS) to analyze four years of search and rescue (SAR) mission data from Colorado to determine the appropriate use of GIS for volunteer-based SAR organizations with limited resources and GIS expertise. GIS can provide more sophisticated analyses of geospatial data than simple mapping technologies, but our findings indicated that complex spatial analysis might not be required on all missions, because the majority of missions were completed within six to ten hours. Instead, new technologies such as tablets with mapping software and online GIS systems that provide quick and easy access to up-to-date geospatial data such as imagery offer capabilities that could improve mission planning. Here we provide a framework in which SAR missions can apply geospatial technologies to aid with missions, identify critical “hotspots,” and enhance postanalysis and training. The work here is highly applicable for nonprofit SAR groups when deciding on what GIS technologies to consider for their areas.  相似文献   

10.
David Lulka 《Urban geography》2013,34(8):1119-1143
Abstract

Nonhuman animals are part of the dynamism that typifies cities, yet prior research has obscured this condition by focusing upon a limited subset of animals and the privatized spaces that contain them. Consequently, previous research provides little guidance in developing a post-human conception of cities. This paper redresses this deficiency by redefining conceptions of “the public” and analyzing data from San Diego's Dead Animal Removal Program (DARP). Commensurate with modern political conceptions, “the public” is defined simultaneously as a spatial formation and (akin to democracies) a quantitative body of bodies. The DARP data indicate the pervasive presence of nonhuman animals in urban environments and the difficulties they face. As a nexus, the DARP illustrates how urban practices and bureaucratic systems reinstantiate “the public” in humanized form through the death and disposal of nonhumans. These hybrid relations challenge geographic methods.  相似文献   

11.
This paper addresses questions of ethnography in geographic fieldwork through research conducted on globalisation and work in Tiruppur, an industrial boomtown in South India. During the last two decades of the twentieth century, Tiruppur town in western Tamilnad State became India's centrepiece in the export of garments made of knitted cloth. This industrial boom has been organised through networks of small firms integrated through intricate subcontracting arrangements controlled by local capital of Gounders from modest agrarian and working‐class origins. In effect, the whole town works like a decentralised factory for the global economy, but with local capital of peasant‐worker origins at the helm. My research explores the historical geographic trajectories linking agrarian and industrial work, and the ways in which these histories are used in the present. In these uses of the past in remaking self and place, I interrogate the self‐presentations of Tiruppur's entrepreneurs, as these “self‐made men” hinge their retrospective narratives of class mobility and industrial success on their propensity to “toil”. This paper explores questions of ethnographic method emerging from a political‐economic context in which globalisation has worked by turning “toil” into capital.  相似文献   

12.
Volunteered geographic information (VGI), OpenStreetMap (OSM), has been used in many applications, especially when official spatial data are unavailable or outdated. However, the quality of VGI remains a valid concern. In this paper, we use the matched results between OSM building footprints and official data as the samples for training an autoencoder network, which encodes and reconstructs the sample populations according to unknown complex multivariate probability distributions. Then, the OSM data are assessed based on the theory that small probability samples contribute little to the autoencoder network and that they can be recognized by the higher reconstructed errors during training. In the method described here, the selected measures, including data completeness, positional accuracy, shape accuracy, semantic accuracy and orientation consistency between OSM and official data, are used as the inputs for a deep autoencoder network. Finally, building footprint data from Toronto, Canada, are evaluated, and experiments show that the proposed method can assess the OSM data comprehensively, objectively and accurately.  相似文献   

13.
Abstract

This article discusses the use of geographic information technologies to assist researchers in the exploration of historical databases. The case study is a pilot project in which we used geographic information systems (GIS) and global positioning systems (GPS) to study the history of the Public Waterfront Act (the “Chapter 91” program), a policy designed to balance private property rights, public interest, and environmental protection in the Massachusetts tidelands. The issues discussed range from the role of GIS in society and its limitations as a representational tool to the ability of current GIS to deal with historical data and to manage temporal attributes.

  相似文献   

14.
地理学在新冠肺炎疫情早期防控中的学术响应及展望   总被引:1,自引:0,他引:1  
重大公共卫生突发事件如新冠肺炎等对区域人类活动有着深刻影响。作为以空间分析和人地关系为主要方法和对象的地理学,在疫情早期防控中的角色贡献以及未来趋势是迫切需要总结和讨论的重要议题。基于2020年1月20日~2月28日的文本数据,着重总结地理学者以及地理学视角下关于疫情的相关研究,地理学在疫情传播与扩散、区域规划与应急、数据与决策支撑等疫情早期防控方面做出了积极贡献,总结归纳了手机信令、百度迁徙数据等移动定位大数据与人工智能、数据挖掘、语义识别等新一代技术方法在疫情防控中发挥的支撑作用,反思提出未来应该在学科理论和防控措施方面,进一步优化风险预测模型、强化应急规划治理、加强国际合作及多学科数据交叉集成共享,从而提升应对重大公共卫生事件的科学性、主动性和高效性,为后疫情时期经济社会管理与空间治理提供科学支撑和依据。  相似文献   

15.
The dynamics of social vulnerability are of key interest to many government agencies and departments. Identifying the geographic distribution of vulnerability within regions, and analysing how localised areas of social need change over time, is a key information requirement for decision-making, and the resultant allocation of resources. Typically, the delineation of areas for the determination of social vulnerability occurs using a combination of political and census boundaries. In many instances, the boundaries of these areas align to natural geographic features such as rivers or lakes. In other cases, a boundary is aligned to a man-made structure such as a road. The boundary may also be arbitrarily positioned based on some measure of distance and not align to any physical feature. In this research, we identify the various boundary types present in a political region. Using two measures of social vulnerability, we assess these boundaries as barriers to the continuity of social vulnerability. From our results, we identify motorways/highways and watercourses as potential barriers. We find no significant effects with lesser road structures suggesting there is no “wrong side of the street”. These results have implications for decision-makers and emphasise the need to recognise the “softness” of boundaries, and consider the relationships between areas, when allocating resources.  相似文献   

16.
Drawing on ethnographic case studies from Madagascar, this research shows that multiple marine conservation projects have institutionalized inequitable access to marine recourses along gendered lines. Despite discursive and institutional shifts toward more “collaborative” and “community-based” conservation programing, there is a deficiency of women’s nominal as well as effective participation in community management organizations. This research shows that conservation organizations’ focus on proximate drivers of marine resource use, or a politics of picking the “low-hanging fruit,” over ultimate drivers such as global commodity chains, places disproportionate emphasis on marine spatial enclosures and restricting specific, and gendered, harvest methods. To address gender bias concerning access to and control over natural resources, we must go beyond the rhetoric of “community involvement” to address gendered inequalities in conservation decision making, and whose interests are served by conservation projects.  相似文献   

17.
18.
马恩朴  蔡建明  郭华  林静  廖柳文  韩燕 《地理学报》2021,76(10):2343-2359
受城市化、地域功能分化、生产要素优化配置和交通网络快速扩展等因素影响,区域之间资源要素的流动已成为区域可持续发展的内在需求。在这种背景下,人类与地理环境互动模式的网络化就要求地理学研究采取全程耦合范式,即将区域内部、区域与周边区域、以及非邻接区域之间的人地互动同时纳入考虑。食物系统作为衔接乡村与城市、以及产地与全球消费市场的产业链和价值链,是开展人地系统近远程耦合研究的重要切入点。基于这种认识,本文在论证理论研究内在依据及外在条件的基础上,将食物系统的构成要素与远程耦合框架相结合,建立“城市化驱动下食物系统近远程耦合的理论框架”并论述该理论框架的具体内涵。以拓展理论框架中的前沿领域为基本导向并结合国家重大战略需求,本文进一步明确了食物系统耦合研究的基本问题和4个亟待突破的优先研究方向。其中,基本问题是食物域的格局特征、时空演化及其动力机制。4个优先方向则包括:耦合社会经济文化变迁与生物地球化学循环的供应链网络人地互动研究;食物系统近远程耦合效应及其调控策略研究;基于食物系统的城乡融合与长效脱贫机制研究;以及面向公共卫生安全的食物系统跨区域、多层次治理研究。本文最后设计了食物系统耦合研究的一般技术路径,研究结果可为进一步的案例实证提供理论支撑和研究思路参考。  相似文献   

19.
“Geographic polarization”, the spatial concentration of “like” voting behavior, is a phenomenon closely related to “partisan polarization”, the intensification of diametrically ideological positions, is understudied, and is critical to the understanding of current American electoral behavior. To date, few studies have examined geographic polarization, and those that do have done so at the scales of regions, states, and counties. However, local influences operating within areas smaller than counties influence voting behavior and can produce geographic polarization. To address these scalar and methodological shortcomings, this research focuses on the smallest political units, precincts, using a case study of the Greater Cincinnati Metropolitan Area. Presidential election data from 1976 through 2008 were collected by precincts, analyzed using spatial statistics, and mapped to examine evolving geographic polarization over this 32-year period. The results measured at the precinct-scale, suggest an increased concentration of partisan behavior and emphasize a local residential spatial pattern of geographic polarization.  相似文献   

20.
Using a mixed set of ethnographic methods including interviews and a structured survey, we evaluate local perceptions about the sustainability of salmon fisheries among fishers of the Cook Inlet region of Alaska. A majority of residents report participating in these fisheries, but we find significant disagreement about their sustainability. Household income and the types of fishing practiced both influence people's responses, and many implicated specific user groups for overharvesting and/or for receiving unfair catch allocations. Drawing on the theoretical areas of information theory and political ecology, we argue that these findings reveal a complex interplay among the practical, social, and political aspects of how local resource users, or “local experts,” develop and communicate their assessments of ecological conditions in a context of conflict. We conclude with notes on future research as it relates to the successful design of local-management and co-management solutions, especially in settings where resources are contested by stakeholders.  相似文献   

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