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31.
Pedestrian navigation has become an important theoretical and practical research topic in many disciplines such as cartography, geographical information science, global and indoor positioning, spatial behavior, psychology, sociology, and neuroscience. Many research studies view pedestrian navigation using process-oriented and goal-directed approaches. However, this paper revisits people’s needs in pedestrian navigation and classifies their needs as three layers: physical sense layer, physiological safety layer, and mental satisfaction layer according to Maslow’s theory. This paper introduces a people-centric framework for pedestrian navigation theory based on these three layers and discusses theoretical challenges for meeting each layer of people’s needs. These challenging theories may represent promising and valuable research and promote usage of pedestrian navigation systems or devices in the future.  相似文献   
32.
Forest tenure reform in the age of climate change: Lessons for REDD+   总被引:1,自引:0,他引:1  
Numerous authors have stressed the importance of guaranteeing and protecting the tenure and human rights of indigenous and other forest-based communities under schemes for reducing emissions from deforestation and forest degradation (REDD, or REDD+); and important international indigenous organizations have spoken out strongly against REDD+. This article examines two specific issues that present risks for local communities: rights to forests and rules for resource use. It draws on the findings of a study conducted by the Center for International Forestry Research (CIFOR) on forest tenure reforms in selected countries in Asia, Africa and Latin America from 2006 to 2008. The study underlines the numerous obstacles faced by communities after rights are won, in moving from statutory rights to their implementation and to access to benefits on the ground. It argues that there is currently little reason to expect better results from national policies under REDD+ without binding agreements to protect local rights.  相似文献   
33.
通过问卷调查,具体分析了吉林省敦化市乡村人群对气候变化趋势和极端冷暖年的感知偏差及人群分异.发现乡村人群对气候变化趋势的感知与科学事实比较符合,由于对变暖转折年代更敏感,因而对变暖的确认度在一些时段与科学事实在变化程度或幅度上存在比较大的偏差.乡村人群对极端冷暖年不如对趋势感知的准确度高.经验积累影响乡村人群对气候变化...  相似文献   
34.
Bjørn Sletto 《Geoforum》2011,42(2):197-210
Conflicts surrounding protected area management often emerge from contested processes of boundary-making. Such productions of bounded conservation spaces are contingent in part on processes of identity formation, where some social groups are legitimized as belonging to conservation units, while others are constructed as out-of-place. This article draws on the literature in postmodern geopolitics and the political ecology of fire to interrogate processes of boundary-making and identity formation in the savanna landscape of Canaima National Park, Venezuela. The institutional culture of the environmental management agency EDELCA is in part premised on narratives of history and indigeneity coupled with a desire for an imagined, forested landscape. Because of the social constructions shaping this institutional culture, the agency maintains an approach to fire management that emphasizes fire suppression. However, an ecological field study suggests that fire suppression is leading to increased fuel loads, especially in ecologically significant boundaries between grasslands and forest. Although these boundary zones are the focus of indigenous practices of prescribed burning, they fall in-between the state management categories of forest and ecotone. As a result, these interstitial spaces become theaters for performances of domination and resistance, leading to contradictory and inconsistent approaches to fire management that place gallery forests at risk.  相似文献   
35.
Views and Visions of Land Use in the United Kingdom   总被引:1,自引:0,他引:1  
As part of a national study aimed at surveying the land use and landscape of the United Kingdom, 1287 surveyors recorded their views and visions of one-kilometre grid squares in which they conducted fieldwork. This study, which took place in 1996, has links to previous national land-use surveys by L. Dudley Stamp (1950) and Alice Coleman (1976, 1977). Of the total sample, 1037 reports are from the observations of school children. Their views relate to six key questions which have been analysed using qualitative research techniques to identify categories of shared responses. Reported in frequency counts, the results highlight a degree of communality in the perceptions of the majority of young people and adults involved. They show their hopes and dreams for a cleaner and varied landscape in the future with more green space, greater provision for well-planned low density housing, and recreation facilities. At the same time their expressed concerns for the management of the environment, housing development, green space provision, recreation and leisure activities indicate a disquiet about the future. This apparent pessimism is most notable in the views for urban locations. For rural locations there is a higher expectation that things will remain more-or-less the same in 20 years time.  相似文献   
36.
高密度脂蛋白胆固醇(HDL-C)可以有效促进人体内胆固醇的代谢外排,其水平的高低与患心血管疾病的风险呈负相关关系,是心血管疾病的预防与保护因素。厘清我国中老年人群HDL-C水平的地理分异特征及环境影响因素,对我国心血管疾病防治工作的开展有重要意义。论文基于中国中老年人纵向追踪调查,利用全局空间自相关、冷热点分析等方法阐释中国中老年人群HDL-C水平的空间分异特征及变化趋势,同时对比引入随机森林回归模型及多元线性回归方法探讨HDL-C水平空间分布的环境影响因素及其指示作用。结果表明:中国中老年人群HDL-C水平表现为女性高于男性、农村高于城镇,具有明显的地域差异性,整体呈现出“北低南高,中间过渡”的分布格局,且北方出现了以内蒙古、河北、辽宁为代表的低值聚集区,南方出现了以广东、广西、云南为代表的高值聚集区;SO2、NO2、降水、气压、PM10和PM2.5是影响中老年人群HDL-C水平差异分布的主要环境因素,其中高浓度的空气污染物是造成HDL-C值较低的危险因素,充沛的降水和低压环境是防治HDL-C值较低的保护因素。因此,今后关于HDL-C血脂异常防控工作在全国各地应注重其空间分布规律,重...  相似文献   
37.
王璐玮  汪涛  张晗 《地理研究》2021,40(12):3314-3332
构建显示性比较优势指数,分析"走出去"全球化下中国医药产业的国际竞争力;识别企业战略连接类型,分析"引进来"全球化下生物医药全球生产网络(GPN)与本土创新网络(IIN)间的战略耦合过程;运用超效率SBM模型,测度GPN-IIN战略耦合目标实现的达成效率,并从静、动态视角探究其时空变化的原因。发现:(1)中国医药产业通过转口、代加工进入北美市场的难度加大,东盟、金砖国家成为其重要的出口对象,与欧盟加强贸易有助于其形成高标准的自由贸易协定网络。(2) 2000—2006年,多数外商直接投资(FDI)企业形成"两头在外"的产业布局,在GPN中处于被俘虏地位,大多内资企业学习能力不足,处于IIN边缘。2007—2013年,部分FDI企业由GPN价值链末端向高端转移,部分内资企业由IIN边缘向核心转移,但转移过程中具有强松脚性。2014—2019年,GPN-IIN战略耦合克服上一阶段嵌入不足、松脚性等问题,两者间的关系通道日益增多和稳固。(3) GPN-IIN耦合绩效经历了"大分散、小集聚→简单结构孕育→局部结构构建→级联秩序分异"的演变,在此过程中技术进步对其促进效果最强,规模效率次之,纯技...  相似文献   
38.
本文以丰富的实际资料,论证了地下水中微量元素锶形成的主要控制因素及其与人群健康的关系。  相似文献   
39.
This essay examines the recent controversy surrounding ‘Safe Schools', a federally-funded education program designed to reduce anti-lesbian, gay, bisexual, transgender and intersex (LGBTI) bullying in Australian schools. Although LGBTI students are known to experience homophobic, biphobic and transphobic verbal and physical abuse at school, opponents of Safe Schools have argued that the Program is both unnecessary and potentially harmful. In the essay, we argue that geographers have valuable contributions to make to this debate, particularly by revealing the ways in which sexuality and gender shape young people's experiences of school spaces.  相似文献   
40.
This article identifies the two dominant discourses that attempt to explain socioenvironmental change from bauxite mining in Eastern India and compares them to empirical material from three proposed mining locations. The anti-mining “life-giving hills” discourse understands the bauxite-bearing hills as an essential part of a wider ecosystem that supports sustainable, indigenous communities. The pro-mining “treasure chest” discourse, on the other hand, sees barren, uninhabited hilltops with rich ore deposits possible to extract for the benefit of the nation without harming nearby forests or communities. It is found that both discourses hold universalizing aspirations not backed up by available evidence. The technical rationality of mining proponents create sweeping generalizations resulting in unmitigated socio-environmental change, while the eco-romanticist opposition fails to see how communities and environments are differentially affected by mining. Two untenable discourses at present underpin seemingly intractable conflict without addressing wider resource politics dominated by political and business elites.  相似文献   
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