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131.
本文根据常规制图方法中居民地注记的定位原则,讨论了注记位置自动查找的方法,将定位中的关键问题——何为最佳注记位置,模型化,使之便于计算机处理,并用实验数据验证此算法的合理性和可行性。  相似文献   
132.
Water science data are a valuable asset that both underpins the original research project and bolsters new research questions, particularly in view of the increasingly complex water issues facing Canada and the world. Whilst there is general support for making data more broadly accessible, and a number of water science journals and funding agencies have adopted policies that require researchers to share data in accordance with the findable, accessible, interoperable, reusable (FAIR) principles, there are still questions about effective management of data to protect their usefulness over time. Incorporating data management practices and standards at the outset of a water science research project will enable researchers to efficiently locate, analyse and use data throughout the project lifecycle, and will ensure the data maintain their value after the project has ended. Here, some common misconceptions about data management are highlighted, along with insights and practical advice to assist established and early career water science researchers as they integrate data management best practices and tools into their research. Freely available tools and training opportunities made available in Canada through Global Water Futures, The Gordon Foundation DataStream, the Digital Research Alliance of Canada Portage Network, Compute Canada, and university libraries, among others are compiled. These include webinars, training videos, and individual support for the water science community that together enable researchers to protect their data assets and meet the expectations of journals and funders. The perspectives shared here have been developed as part of the Global Water Futures programme's efforts to improve data management and promote the use of common data practices and standards in the context of water science in Canada. Ten best practices are proposed that may be broadly applicable to other disciplines in the natural sciences and can be adopted and adapted globally.  相似文献   
133.
白成军  韩旭 《测绘学报》2013,42(3):447-452
西晋人裴秀的《制图六体》是研究中国古代测绘技术发展历程的重要历史文献资料。本文基于以往研究成果,结合裴秀编制《禹贡地域图》的基本方法和缘由,充分考量当时的测量技术发展水平,对《制图六体》进行了整体析读,在此基础上指出:作为六体核心的“准望”是中国古代所有精确测量的泛称,《制图六体》是以裴秀为代表的地图编绘者对地图测绘提出的基本要求总结,也是裴秀时代采用“计里画方”的绘图方法、利用区域地图结合文字考证绘制全域性地图的最好诠释。这一研究,补正了以往研究中的不足之处。  相似文献   
134.
GIS原理教学中的问题与初步思考   总被引:4,自引:0,他引:4  
地理信息系统(GIS)原理是GIS专业或其相关专业的专业基础或必修(限选)课,对GIS人才培养具有非常重要的作用,但由于种种原因,GIS原理在教学方面仍存在多方面的问题与不足。本文首先分析了大学本科GIS原理在教学内容、实验与实习及教学手段等方面存在的问题,然后针对这些问题根据自己的教学体会提出了一些相应的解决办法与建议。  相似文献   
135.
牛汝辰 《测绘科学》2007,32(6):202-203,170
此文是作者继前几年发表《清代测绘科技的辉煌及其历史遗憾》一文的续文。此文回顾了自秦代至元代我国地图测绘的主要成就,特别是我国领先于世界的地图成果,这包括秦代大型地形模型图,东晋裴秀的"制图六体",宋代的石刻《禹迹图》和地形模型图,元代朱思本的画方地图《舆地图》和札马鲁丁的世界第一个地球仪等。可以说自秦至元我国的地图测绘技术始终处于世界前列。  相似文献   
136.
Complex intersecting social, economic and environmental dilemmas in Australia's Cape York Peninsula present a number of challenges for planners seeking to develop and implement land use and natural resource management (NRM) plans. There have been five different attempts at land use and NRM planning in Cape York Peninsula over the last 20 years. These processes have (to greater or lesser extents) failed to deliver community-owned and government-supported plans to guide development and/or the management of the region's natural resources. The region is remote, sparsely populated, and home to a significant Indigenous population. Much of the contestation within the region surrounds the access, use and ownership of the region's internationally valuable natural resources. This paper reviews, from the literature, the relevancy and applicability of criteria for best practice planning and governance. A range of identified best practice governance and planning principles are applied to assess the governance arrangements for planning in the Peninsula. The paper finds that decision-making arrangements for land use and NRM planning in the Peninsula are still in their infancy and are inadequate to support effective outcomes. The paper concludes that broader attention to best practice principles in governance for planning is needed to improve planning outcomes.  相似文献   
137.
Collaborative management arrangements are increasingly being used in fisheries, yet critical questions remain about the conditions under which these are most successful. Here, we conduct one of the first comprehensive tests of Elinor Ostrom's diagnostic framework for analyzing social–ecological systems to examine how 16 socioeconomic and institutional conditions are related the livelihood outcomes in 42 co-management arrangements in five countries across the Indo-Pacific. We combine recent developments in both theory and modeling to address three key challenges among comparative studies of social–ecological systems: the presence of a large number of explanatory mechanisms, variables operating at multiple scales, and the potential for interactions among socio-economic and institutional factors. We find that resource users were more likely to perceive benefits from co-management when they are more involved in decisions, were aware that humans are causal agents of change in marine systems, were wealthier, were not migrants, were in villages with smaller populations and older co-management arrangements, and had clearly established boundaries. Critically, we quantify a number of key interactions between: wealth, dependence on marine resources, involvement in decision-making, and population size that have strong implications for co-management success in terms of livelihood benefits. This study demonstrates that context plays a critical but identifiable role in co-management success.  相似文献   
138.
近十年来,3维地图得到了迅速的发展,但是对于3维地图的定义并未统一,而对于3维地图的设计也未形成一定的标准。结合相关的文献,笔者认为扩展人类的空间认知手段和范围才是3维地图的本质目的所在,其定义应根据其是否具备超2维的感知效果来确定,而3维地图的设计原则也应从3维感受效果和新的符号视觉变量体系来考虑,同时充分利用2维地图信息的辅助作用。  相似文献   
139.
Education for Sustainable Development (ESD) is a cross-curricular approach that needs to be accommodated in all subjects in the training of students as recommended by UNESCO. This South African case study of preservice geography students is presented for the purpose of understanding how they experienced systems thinking and a cooperative teaching strategy. A qualitative research approach was applied as the research design. Interpretation of the data was done through thematic analysis, which indicated that exposure to the pedagogic approach bore positive results. Teaching and learning strategies promoting the integration of ESD should form part of the training of geography students.  相似文献   
140.
厦门湾深水航道资源开发的探讨   总被引:1,自引:1,他引:0  
张培辉 《台湾海峡》2000,19(2):244-248
本文从分析厦门湾航道资源现状入手 ,论述了厦门湾开发深水航道的迫切性 ,提出了厦门湾深水航道资源开发原则和布局。这些原则和布局可为今后厦门湾港口、航道资源开发提供科学依据。  相似文献   
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