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151.
分析了3S高新技术学科的特点,针对工科学生的学科背景,以郑州大学GIS专业全球定位系统和数字摄影测量学为例,探讨了这些学科的教学方法。主要包括:随时掌握学生的思想状况、扩大教学内容的新颖性与信息量、采取灵活多样的课堂教学方法、注重培养学生动手能力等。三年来的教学实践证明,这些措施大大提高了学生的学习积极性与效率,效果显著。  相似文献   
152.
论述了城市基础测绘部门开发公众地理信息平台的必要性和优势,分析并讨论了公共地理信息服务平台中的公众地理信息服务平台、基础地理信息服务平台和政务地理信息服务平台在数据内容、功能框架、网络体系、服务对象上的不同,以广州市公众地理信息服务平台的开发为例,详细介绍了该平台的数据内容、功能框架和系统特色,该平台对其他城市开发类似的公众地理信息服务平台具有一定的参考作用。  相似文献   
153.
地震是极其严重的自然灾害,有可能造成重大伤亡和经济损失。由于城市中人口高度聚集,地震发生时,需将受灾居民快速疏散至应急避难所,因此,应急避难所选址的合理性至关重要。本文提出1种可用于解决选址问题的多准则选址模型,并提出了求解模型的方法。该方法分为3个步骤,首先选择候选应急避难所,其次分析候选避难所的服务范围,最后确定应急避难所的位置。通过案例研究,论证了多准则选址模型在地震应急避难所规划中的有效性。  相似文献   
154.
The Western Yunnan Earthquake Predication Test Site set up jointly by the China Earthquake Administration, the National Science Foundation Commission of America, and United States Geological Survey has played an important role in development of early earthquake research work in China. Due to various objective reasons, most of the predicted targets in the earthquake prediction test site have not been achieved, and the development has been hindered. In recent years, the experiment site has been reconsidered, and renamed the “Earthquake Science Experimental Site”. Combined with the current development of seismology and the practical needs of disaster prevention and mitigation, we propose adding the “Underground Cloud Map” as the new direction of the experimental site. Using highly repeatable, environmentally friendly and safe airgun sources, we could send constant seismic signals, which realizes continuous monitoring of subsurface velocity changes. Utilizing the high-resolution 3-D crustal structure from ambient noise tomography, we could obtain 4-D (3-D space + 1-D time) images of subsurface structures, which we termed the “Underground Cloud Map”. The “Underground Cloud Map” can reflect underground velocity and stress changes, providing new means for the earthquake monitoring forecast nationwide, which promotes the conversion of experience-based earthquake prediction to physics-based prediction.  相似文献   
155.
Earthquakes are a serious natural disaster faced by countries all over the world. Research on earthquake hazard mitigation are important parts of earthquake science and is a feature of China''s development of earthquake science. In recent years, the Ministry of Science and Technology (MOST) of the People''s Republic of China, the National Natural Science Foundation of China (NSFC) and the China Earthquake Administration (CEA) have attached great importance to basic research on earthquake hazard mitigation, and new opportunities and challenges have emerged. This paper collects the applications and approvals of the National Key R&D Program and the NSFC projects undertaken by the research institutes of the CEA system in recent years. The CEA system has received funding in the 13th “Five-year Plan” for “Monitoring, Early Warning and Prevention of Major Natural Disaster”. The implementation of these projects is expected to provide support for the basic science and applied research of the CEA system. In the NSFC, the number of applications from the CEA system is relatively stable, and the funding rate is slightly higher than the average for the department of earth science. Although no detailed statistical analysis has been performed, the CEA system still has room for improvement in the application of talent and major programs. I hope that the brief review of new opportunities that have arose in recent years described in this article can provide some background and new thinking for future challenges.  相似文献   
156.
刘涵  张侠 《极地研究》2017,29(2):245-255
近些年来南极科研越来越受到世界各国的重视,作为《南极条约》的发起者和南极条约体系的管理者,美国始终站在南极科学研究前沿,对维护其国际南极事务领导地位有着重要意义。1953—2016年美国国家科学基金资助了7 759个南极科研项目,通过统计分析对项目投入进行以下4个方面的分析:南极项目投入、南极科研各学科投入、科研大项目以及合作机构。研究发现:(1)1953年至今,美国国家科学基金会(NSF)对美国南极科研项目的资助力度和重视力度不断增加,促进了美国南极政策的落实和发展;(2)美国各大科学指导机构出台的前瞻性文件对引领美国南极科考发展方向起到重要作用;(3)NSF充分利用各高等院校和研究机构的资源设施,搭建科研支撑平台,与之展开长期南极科研项目合作;(4)NSF重视科研大项目的开展,这些大项目站在南极科学前沿,引领美国南极科研更好地发展;(5)NSF通过学校、社会、媒体多个渠道开展南极教育,增进群众对南极了解并培养科研人员来维护美国在南极的科考领先地位。上述研究发现为中国南极科研政策制定提供了相应的启示。  相似文献   
157.
Traditionally, the ‘social licence to operate’ (SLO) refers to the societal expectations imposed on corporate and commercial activities, often displayed by the willingness for corporations to go beyond the requirements of formal regulations. Alternatively, this paper investigates the emerging influence of the SLO in shaping government decisions regarding the use and impact of the marine environment and its resources. Using expert interviews, text analysis and case study analysis, this research delineated the contemporary SLO as it has manifested in Australian marine governance, with the results indicating that this is potentially occurring at a pace faster than can be systematically reacted to within the current political decision-making processes. Under these emerging conditions, the risk has been identified that traditional government decision-making and stakeholder consultation processes are lagging in their capacity to adapt to ensure that public policy processes can support and engage in this shifting dialogue and ensure the influence of information is appropriately weighted. This research highlights an emerging adjustment of community presence in marine governance and the immediate complexities and challenges this creates for government decision-making. In particular, it begins to explore the interaction of differing information, how this information is carried through communication channels, stakeholder behaviour, approaches to withholding or granting a SLO and the responsibility this carries.  相似文献   
158.
赵伦山 《地学前缘》2005,12(1):288-293
地球科学和地球化学的进展,不但加深和扩大了对地球的认识和理论成果,同时也总结提炼出了全新的科学思维方法。复杂性理论和系统思维是科学认识论的一次飞跃。现代地球化学建立了较完整的理论和方法体系,给地质科学认知地球提供了依据和支撑。作者论证了系统思维和逻辑演绎法相结合的思维方式,是研究和认识地球复杂巨系统以及推动地球科学理论创新的指导思想,并提出了运用现代地球化学理论构架和方法体系,综合地球科学系统思维与逻辑思维相结合方向的地球化学认知模型,为深入研究地球物质能量系统的行为和解决人类面临的资源、环境和灾害问题提供新的思路。  相似文献   
159.
This study aims to prepare a detailed GIS-based geomorphological map accompanied with landfill sites of Dhaka city area which can be used for multipurpose functionality. Attainment of the geomorphological map is based upon interpretation of the oldest available aerial photographs (1:40,000) and contemporary topographic maps (1:8000) which reflect almost pre-urban ground of Dhaka. Randomly distributed 160 boreholes have been used to prepare representative soil profiles (RSP) to identify the near-surface lithology of the geomorphological units. The study reveals that 13 out of 18 low-lying geomorphic units, comprising 65% of the total area demand landfill practices for urban development. Landfill sites have been merged with urban growth on each low-lying geomorphic unit using a spatially enhanced fused image of IRS-1D PAN and ETM+ bands 5, 4 and 3, acquired February 2000 and 2002, respectively. We found that 43% area of the total low-lying geomorphic units experience fill practices so far. The fill sites have been differentiated into four classes based on their relative thickness. Integration of fill classes with geomorphological map shows the urban dynamics of Dhaka city area till 2002. Due to GIS integration, this map can be rapidly updated to demonstrate temporal modifications in urban ground. It can be used effectively in different geomorphological hazard mapping and urban land-use practices.  相似文献   
160.
基于人工神经元网络的空间知识表达与推理方法研究   总被引:1,自引:0,他引:1  
分析了智能决策支持系统的结构,通过比较指出了基于符号的知识表达与推理方法的不足,阐述了基于神经网络的知识表达与推理的方法,并认为神经网络方法可作为智能空间决策支持系统中符号方法的替代或补充,并通过实例验证了基于神经网络的不确定空间知识表达与推理的有效性.  相似文献   
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