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711.
Google Earth软件具有免费、开放、简单易用等特点,对丰富教学资源和改善教学方法具有重要意义。基于GoogleEarth平台,在《城市遥感技术》教学中,对于遥感成像和影像特征、遥感解译标志及方法、城市遥感影像的信息提取、城市遥感专项调查等章节的理论教学,应重点运用遥感影像的搜索、标注和显示等功能;对于遥感影像地图制作、地类信息提取、演变信息提取等实验教学,应重点运用采集、存储、查询、分析、显示和输出等集成功能。实践表明,Google Earth值得在地学教育模式革新中推广。  相似文献   
712.
通过对KML文件结构的分析,利用UltraEdit软件制作KML文件,笔者总结出一种在Google Earth中批量标记点位的方法.  相似文献   
713.
Google Earth作为一款电子浏览地图,由于其富含的多源地理信息,被各行业的人士所钟爱,尤其在测绘行业内其巨大的辅助作用更是凸显无疑,在本文中笔者结合自身经验,将Google Earth在测绘外业生产中的辅助作用进行一一叙述,总结出提高作业效率、降低劳动强度、方便快捷的生产方法。  相似文献   
714.
岩溶关键带及其碳循环研究进展   总被引:1,自引:0,他引:1  
岩溶关键带的范畴包含了大气-(降水)-植被-土壤-裂隙-基岩-水组成的“碳-水-钙”循环强烈的表层岩溶带以及岩溶管道-洞穴-地下河-隔水层组成的巨大岩溶地下空间,岩溶关键带碳循环是岩溶地球系统科学研究的前沿方向。总结概括了岩溶地球系统科学发展至今的岩溶关键带范畴内碳循环及其对大气CO2源汇效应的研究成果,包括早期碳运移模型、当前主流的区域岩溶碳汇量的计算方法和结果以及“生物碳泵”的新发现等,讨论了当前岩溶碳循环研究框架过于单一或不一致以及碳周转时间尺度等问题,提出应对岩溶关键带碳输入、赋存以及碳输出的各个环节做出系统化监测,通过联网在线高分辨率监测站点的建设以及“3S”技术实现点位到区域的研究,使岩溶碳汇在全球碳循环模型中的重要性更具说服力。  相似文献   
715.
The determination of the stress state in backfilled stopes is an important step for assessing the behaviour of mine openings and for designing barricades. Most previous analyses have considered only the 2D case (plane strain condition) and neglected the effect of pore water pressure. In this paper, a three-dimensional solution is proposed for totally or partly submerged backfill. The new solution gives the normal stresses along the vertical and horizontal axes, with the effect of a surface load on the backfill. The solution is validated using laboratory experimental results taken from the literature. The good agreement obtained between the proposed analytical solution and laboratory test results indicates that this new solution provides a realistic evaluation for both the total and effective stresses in vertical backfilled stopes.  相似文献   
716.
Roaldite – Fe4N – has been identified in the São Julião de Moreira iron meteorite using electron backscatter diffraction (EBSD) and simultaneously acquired energy-dispersive x-ray spectroscopy (EDS). Mean-periodic-number images derived from raw EBSD patterns confirm this phase by an even higher spatial resolution compared to EDS.Roaldite appears in the form of systematically and repetitively aligned plates. Despite the locally heavy plastic deformation, it is shown that the origin of the oriented precipitation of roaldite is linked to the orientation of the kamacite matrix. Roaldite can be considered to be precipitated from kamacite using an inverse Kurdjumov-Sachs (K-S) or Nishiyama-Wassermann (N-W) orientation relationship. A more accurate discrimination is impossible due to the accumulated shock deformation, which blurs the local reference orientation of kamacite. The habit plane of roaldite is found to be {112}R, which is most likely parallel to {120}K of kamacite. Some of the roaldite plates contain two orientation variants which repeatedly alternate. Their misorientation angle is about 12°.  相似文献   
717.
Most geologists would argue that geoscientific knowledge, experience, and guidance is critical for addressing many of society’s most acute environmental challenges, yet few geologists are directly engaged in current discourses around sustainable development. That is surprising given that several attributes make modern geoscience well placed to make critical contributions to contemporary sustainability thinking. Here, we argue that if geoscientists are to make our know-how relevant to sustainability science, two aspects seem clear. Firstly, the geoscience community needs to substantially broaden its constituency, not only forging interdisciplinary links with other environmental disciplines but also drawing from the human and behavioral sciences. Secondly, the principles and practices of ‘sustainability’ need to be explicitly integrated into geoscience education, training and continued professional development.  相似文献   
718.
基于大数据和人工智能技术的数据驱动科学范式推动地球科学研究发生了变革。作为地球科学的重要分支,现代矿床学经历了百余年的发展,已经积累了海量的数据资料,这些数据的流通和共享是发挥其资源价值的关键。文章介绍了中国“地质云”与全球矿产资源储量动态评估数据库、澳大利亚深部地球探测计划AuScope、美国矿产资源在线空间数据库、国际经济地质学家学会(SEG)Geofacets数据库、美国标准普尔公司SNL Metals&Mining数据库等国际主要矿床数据库的情况;同时,列举了应用大数据思维和人工智能方法在区域成矿规律、矿床成因机制、矿床类型判别、资源潜力评价、战略咨询等方面取得的若干重要进展。文章提出,未来在深时数字地球国际大科学计划的平台下,整合全球海量矿床数据,建设开放、共享、统一的矿床大数据平台势在必行。  相似文献   
719.
The history of the determination of the Earth's age is interesting in two ways. First, it is a great school for understanding the genesis of a scientific theory. It stands at the crossroads of almost all scientific disciplines, and also philosophy or even theology. This history shows how what one may well call a “scientific truth” was established through polemics. Second, that age of 4.567 billion years is not just another figure in the series of ages that would be of concern only to astrophysicists; this scale is the only one that makes it possible to understand the genesis of the marvelous order of the solar system (that Newton attributed to God) and the fantastic complexity of Life on Earth.  相似文献   
720.
http://dx.doi.org/10.1016/j.gsf.2016.10.005   总被引:5,自引:4,他引:1  
The Earth was born as a dry planet without atmosphere and ocean components at 4.56 Ga, with subsequent secondary accretion of bio-elements, such as carbon (C), hydrogen (H), oxygen (O), and nitrogen (N) which peaked at 4.37–4.20 Ga. This two-step formation model of the Earth we refer to as the advent of bio-elements model (ABEL Model) and the event of the advent of bio-elements (water component) as ABEL Bombardment. It is clear that the solid Earth originated from enstatite chondrite-like dry material based on the similarity in oxygen isotopic composition and among other isotopes. On the other hand, Earth's water derives primarily from carbonaceous chondrite material based on the hydrogen isotopic ratio. We present our ABEL model to explain this enigma between solid Earth and water, as well as secondary accretion of oxidizing bio-elements, which became a precursor to initiate metabolism to emerge life on a highly reductive planet. If ABEL Bombardment had not occurred, life never would have emerged on the Earth. Therefore, ABEL Bombardment is one of the most important events for this planet to evolve into a habitable planet. The chronology of ABEL Bombardment is informed through previous researches of the late heavy bombardment and the late veneer model. ABEL Bombardment is considered to have occurred during 4.37–4.20 Ga, which is the concept to redefine the standard late heavy bombardment and the late veneer models. Also, ABEL Bombardment is the trigger of the transition from stagnant lid tectonics to plate tectonics on this planet because of the injection of volatiles into the initial dry Earth.  相似文献   
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