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221.
潜在自行车出行是指可能会使用自行车作为交通工具的出行,评估潜在自行车出行需求能够帮助指导城市自行车资源配置方案的优化。大规模手机位置数据蕴含丰富的人群移动信息,而且具有大样本、低成本的特点,能够用于评估城市潜在自行车出行需求。本文结合自行车出行的时间和距离特征,提出一种基于大规模手机位置数据的潜在自行车出行需求评估方法。该方法以单次出行为分析单元,从手机用户的轨迹中提取出具有短距离出行特征和公共交通接驳出行特征的移动轨迹段,并根据该移动轨迹段评估潜在自行车出行需求。基于该方法,利用上海市大规模手机位置数据评估上海市潜在自行车出行需求并分析其时空分布特征,发现在空间上,潜在自行车短距离出行需求主要分布在城市中心和郊区的商业中心,而公共交通接驳的自行车需求主要分布在郊区。在时间上,上午,自行车出行需求从非中心城区向中心城区聚拢;晚上,上海市自行车出行骑车与停车需求从中心城区向非中心城区扩散。  相似文献   
222.
Many studies have shown a general decline of public concern about climate change or vice versa a rise in public climate-change skepticism, in particular in the U.S. and other Anglo-Saxon countries. There is a vivid debate on whether this is a global phenomenon, on which factors explain the decline, and on the broader societal implications of these trends in the context of the transformation toward a low-carbon society. We add to this literature by presenting the results of a recent general population survey in Germany in which we looked for systematic linkages between public climate-change skepticism on one hand, and energy preferences and political participation on the other. Germany is an interesting testbed as it is currently involved in a large-scale restructuring of its system of energy supply toward renewable energy sources (the “Energiewende”). Our results indicate that climate-change skepticism has not diffused widely in Germany, but that it correlates with less support of renewable energy sources. However, skepticism correlates negatively with political participation, and there is no strong political outlet for public climate-change skepticism in Germany. Alternative potential barriers for the successful implementation of the “Energiewende” are also discussed.  相似文献   
223.
对数字时间戳服务系统的结构和基本工作方式进行了分析,详细讨论了该系统在实际应用中需要解决的问题并给出了数字时间戳服务系统的设计。  相似文献   
224.
2022年,中国地质学会迎来了百年华诞,为进一步扩大百年庆典活动的影响力,于2021年6月向社会公开征集活动标识。经遴选,拟启用下图作为中国地质学会百年华诞庆典活动唯一指定标识。  相似文献   
225.
针对省级公共气象服务系统业务需求,结合四川省现有气象服务产品和信息网络实际,采用先进网络服务技术,提出了省级公共气象服务系统的整体架构设计,包括省—市—县级基础服务产品的集成、特色产品的生产、服务对象的分类等,旨在通过在四川省公共气象服务系统的建设与应用实践,将此设计提升为一种通用模型向全国推广,提供业界借鉴与参考。该系统于2013年6月正式为用户提供服务,应用实践表明,该系统高效、稳定可靠、资源利用率高、实用性强。目前该气象服务系统模式已经在云南推广。  相似文献   
226.
海南省不同人群对高温热浪及其影响与适应的感知分析   总被引:3,自引:0,他引:3  
为了分析海南省不同人群对高温热浪及其影响与适应的感知程度,抽取海南省18周岁以上居民1 448名作为调查对象进行问卷调查。结果显示,调查对象对高温天气相关知识熟悉程度较低,仅有4.2%的居民非常熟悉,但对高温产生原因和未来变化趋势都有较为正确的认识。高温天气对海南省居民健康有较大的不利影响,九成以上的调查对象都曾在高温天气中出现不适,部分人群因此前往医院就诊。高温预警后,约77%的调查对象都能采取有效措施进行防御,但60岁以上的人群采取有效防护措施的比重相对较低,因此在高温天气中该类人群应加强高温防护。  相似文献   
227.
《The Journal of geography》2012,111(6):268-269
Abstract

College enrollment and Association of American Geographers membership data reveal a significant deficit in minority participation in geography and environmental science. The author asserts that this dearth may have its origin at the K-12 level, where science subjects are presented in a manner that alienates socioeconomically disadvantaged pupils. With recent research indicating that low-income and nonwhite communities are disproportionately affected by environmental degradation, it is pertinent that methods be developed to increase the number of minority students choosing to pursue environmental careers. Involving students directly in projects investigating the pollution in their communities aids in enhancing student interest. By participating in a lead (Pb) contamination study, students are introduced to several geographic subdisciplines including cartography, demography, and environmental geography. Students also acquire skills in spatial analysis, map interpretation, and graphic design. Complementing basic lead-soil field investigations with geographic information systems, spreadsheet, and/or computer mapping software, offers students a valuable high-tech learning experience.  相似文献   
228.
Two small high-Arctic glaciers (Longyearbreen and Larsbreen) on Svalbard (78°N 15°E) were studied with respect to glaciological and hydrological characteristics. Fieldwork during the melting season of 1993 and 1994 was coupled with digital map analysis based on high-resolution digital elevation models (DEM) to reveal the dynamics and temperature regime of small glaciers in a high-Arctic environment, and its relationship to the material transport and sedimentation of these glaciers. The study showed Longyearbreen and Larsbreen to be low activity glaciers, cold-based with temperate patches, and thus having a low potential of basal erosion. The transport of ions and suspended solids in the glacial meltwater implies storage of material in and around the glacier which comes into contact with the meltwater. The study suggests that small Arctic glaciers couple the slope system with the fluvial system and therefore build a highly effective denudation system. Small polythermal glaciers are therefore important in understanding Pleistocene and Holocene landform development in cold regions.  相似文献   
229.
Recently, increased attention has been paid to the importance of everyday landscapes in the Western world, and a stronger political will to involve local participation in planning processes has emerged. The authors discuss the implementation of the political will to engage the Norwegian public in local heritage planning and whether or not this new role can have a mobilising effect on heritage protection. In Norway, cultural heritage managers have established methods for identifying valuable heritage assets in cultural historic landscapes. As increased responsibility for cultural heritage management is given to municipalities, more municipalities are making their own heritage plans to improve local heritage management. The article investigates how cultural heritage management in everyday landscapes is taking place, how heritage plans are developed, how local knowledge is involved, and what assets local residents appreciate in their environment, based on an in-depth study of two medium-sized Norwegian regional towns. The results show that local stakeholders were often invited to participate in planning processes, but that their contributions were largely kept out of official plans at the final stage. Further, the study revealed that memories and personal histories related to heritage appreciations are important elements in building identity, both at a personal level and at a local level.  相似文献   
230.
The UK is witnessing a new line in political debate around new nuclear energy generation as one potential feature of future energy policy, specifically for contributing to climate change mitigation alongside energy security. Little is known about how ordinary citizens might be responding to this reframing. This paper reports the results from a major British survey (n=1491) undertaken in the autumn of 2005. The consistent message is that while higher proportions of the British public are prepared to accept nuclear power if they believe it contributes to climate change mitigation, this is a highly conditional view, with very few actively preferring this over renewable sources given the choice. People see both climate change and nuclear power as problematic in terms of risks and express only a ‘reluctant acceptance’ of nuclear power as a ‘solution’ to climate change. The combined data from this survey can also be interpreted as an indication of the complexity surrounding beliefs about energy futures and the difficulty of undertaking simplistic risk–risk tradeoffs within any single framing of the issues; such as nuclear energy versus climate change. The results also indicate that it would be unwise, in the UK as elsewhere, to simplistically assume that there exists any single or stable public ‘opinion’ on such complex matters. We conclude with a discussion of the role and implications of the survey evidence for the policy process.  相似文献   
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