共查询到20条相似文献,搜索用时 203 毫秒
1.
2.
通过对我国明末清初测绘科技的回顾,分析了明末清初西方传教士来华传教及科技交流对我国测绘科技的影响,对当前我国测绘科技发展的人文环境和社会背景做了深入探究,例举了清初我国与传教士合作开发全国地图测绘的全过程、取得的成果和使用的方法,在此基础上深入分析了这一时期测绘科技的辉煌成就及其基因后期的“闭关主义”政策和“天朝中心说”的自大守旧等人文背景和文化传统及科技政策的失误所造成的诸多历史遗憾。 相似文献
3.
4.
晚清时期,西方测绘技术的流入,张之洞营造的近代文明大环境,及1889年编制《大清会典舆图》的需求,使得湖北第一次有计划地实施了测绘人员培训计划,成就了湖北测绘队伍的壮大及湖北测绘事业最初的发展。1892年,张之洞委派邹代钧任总纂, 相似文献
5.
一、概述 房产测绘作为一门独立的测绘科目己从地籍测量系中分列开来,具有自己特点的测量模式。房产测量的目的和任务就是采集和表述房屋以及房屋用地的有关信息,为房地产管理,尤其是为房屋的产权、产籍管理提供可靠成果资料。房产测绘工作重点集中在房屋产权面积测绘和城镇房产平面图修测上。房屋和房屋用地的信息的动态性,房产基础图形的修测成了房产测量的一项长期的主要任务。在西方发达国家,城市不动产和产权变更量也在lO%以上。据统计,中国由于经济的快速发展,城市房产变更测绘量也将超过10%。房产测绘任务主要分为产权面积测绘为主的项目测绘和以城市房产图修测为主的基础测绘两大项目。目前中国各大城市房产测绘工作以产权面积为主的测绘己日趋完善,但开展房产平面图修测工作的却为数不多。笔者从事房产平面图修测工作多年,从城市变更测量的技术层面上做一些探讨。 相似文献
6.
7.
通过对我国明末清初测绘科技的回顾 ,分析了明末清初西方传教士来华传教及科技交流对我国测绘科技的影响 ,对当时我国测绘科技发展的人文环境和社会背景做了深入探究 ,例举了清初我国与传教士合作开展全国地图测绘的全过程、取得的成果和使用的方法 ,在此基础上深入分析了这一时期测绘科技的辉煌成就及其因后期的“闭关主义”政策和“天朝中心说”的自大守旧等人文背景和文化传统及科技政策的失误所造成的诸多历史遗憾。 相似文献
8.
9.
浅议中国新闻地图的发展现状冯志强(中国科学院长春地理研究所130021)一、国际学术界对新闻地图的研究地回应用于新闻报道,在世界上许多国家由来已久,也很普遍。郑州测绘学院高俊教授曾提到,海湾战争期间,西方国家报纸刊登了上百幅地图,而我国仅登了7幅。事... 相似文献
10.
11.
《International Journal of Digital Earth》2013,6(1):80-87
Abstract Cultures throughout the world are associating with the rivers. People depend upon the rivers and their tributaries for food, water, transport, and many other aspects of their daily lives. Unfortunately, human beings have not calculated the accurate lengths for the great rivers even today. The lengths of the rivers are very different in popular textbooks, magazines, atlases and encyclopedias, etc. To accurately determine the lengths of the principal rivers of the world, the combination of satellite image analysis and field investigations to the source regions is proposed in this paper. The lengths of the Nile, Amazon, Yangtze, Mississippi, Yellow, Ob, Yenisey, Amur, Congo and Mekong, with lengths over or close to 5000 km, were calculated using the proposed method. The results may represent the most reliable and accurate lengths of the principal rivers of the world that are currently achievable. 相似文献
12.
13.
软科学这一术语是70年代在国外提出的.然而30多年以来,它在国外不仅未得到普遍的承认,而且对软科学的定义也还未能达成大体上一致的共识.而在改革开放后的中国,出于决策科学化和民主化的需要,经过一些领导人的提倡和支持,特别是通过1986年召开的软科学座谈会及1994年召开的全国软科学工作会议,软科学事业得到了蓬勃的发展.据初步统计,截止1998年底全国共有软科学研究机构1224个,研究人员32655人,初步形成了一支较为强大的研究队伍,并取得了数百项覆盖多个领域的研究成果,为支持各级各类的决策发挥了一定的作用. 相似文献
14.
15.
Tobias Nilsson Benedikt Soja Kyriakos Balidakis Maria Karbon Robert Heinkelmann Zhiguo Deng Harald Schuh 《Journal of Geodesy》2017,91(7):857-866
The very long baseline interferometry (VLBI) Intensive sessions are typically 1-h and single-baseline VLBI sessions, specifically designed to yield low-latency estimates of UT1-UTC. In this work, we investigate what accuracy is obtained from these sessions and how it can be improved. In particular, we study the modeling of the troposphere in the data analysis. The impact of including external information on the zenith wet delays (ZWD) and tropospheric gradients from GPS or numerical weather prediction models is studied. Additionally, we test estimating tropospheric gradients in the data analysis, which is normally not done. To evaluate the results, we compared the UT1-UTC values from the Intensives to those from simultaneous 24-h VLBI session. Furthermore, we calculated length of day (LOD) estimates using the UT1-UTC values from consecutive Intensives and compared these to the LOD estimated by GPS. We find that there is not much benefit in using external ZWD; however, including external information on the gradients improves the agreement with the reference data. If gradients are estimated in the data analysis, and appropriate constraints are applied, the WRMS difference w.r.t. UT1-UTC from 24-h sessions is reduced by 5% and the WRMS difference w.r.t. the LOD from GPS by up to 12%. The best agreement between Intensives and the reference time series is obtained when using both external gradients from GPS and additionally estimating gradients in the data analysis. 相似文献
16.
17.
18.
In this letter, we are trying to resolve the electromagnetic problem for the movements of the superconducting particles of the protoplanetary cloud in the magnetic field of Saturn. The force of levitation (Meissner-Ochsenfeld phenomenon) is introduced to the field of planetary science for the first time. It is shown from our theoretical analysis that rings of Saturn might have a superconducting origin, and rings might levitate within magnetic equator plane of the planet. 相似文献
19.
20.
跟踪世界发展动态 致力地球重力场研究 总被引:12,自引:6,他引:12
宁津生 《武汉大学学报(信息科学版)》2001,26(6):471-475
比较系统、扼要地叙述了笔者所在单位40余年来坚持跟踪世界发展动态,致力于地球重力场理论和方法的研究,并从教学和生产需要出发,在地球重力场研究方面所获得的一些有理论意义和实用价值的成果。 相似文献