共查询到18条相似文献,搜索用时 46 毫秒
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2012年5月21~22日,由国际测量师联合会、国际海道测量组织和国际制图协会三大国际机构组成的国际海道测量师和海图制图师培训资格认证委员会第35届年会,在阿根廷首都布宜诺斯艾利斯召开。来自美国、英国等10余个国家的专家,对海军大连舰艇学院海洋测绘系代表中国参加申报的国际海道测量师/国际海图制图师A级培训资格认证材料进行了审定,并分别进行了现场答辩,最终全票通过。 相似文献
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Larry P. Atkinson Thomas N. Lee Jackson O. Blanton Gustav-Adolf Paffenhfer 《Progress in Oceanography》1987,19(3-4)
During the summer of 1981 a large scale sampling effort took place in the shelf waters of the southeastern United States. The goal of this effort was to quantify the effect of the intrusion of deep Gulf Stream water into these shallow, euphotic waters. By making repeated hydrographic measurements over the entire shelf area, the actual volume of the intrusions was determined. Two main intrusion events were observed: one in June and early July and a second in late July and early August. The intruding water entered the shelf in the region south of St Augustine and was transported northward by the mean northward shelf circulation. The subsurface cold water mass was isolated from the Gulf Stream by a ridge of warmer water along the shelf break.The intrusions resulted in increased stability in shelf waters with vertical temperature gradients as high as 10°C m−1. The potential energy in the stratified shelf waters typically ranged from 1000 to 2000 J m−2 that would require 2 to 4 mW m−2 to mix. However, since only 0.1 to 1.0mW m−2 was available from wind and tidal mixing, the water column stayed stratified in most cases.The amount of nitrate transported onto the shelf was determined by two methods: direct observation by synoptic cruises and transport measurements using current meter arrays. Both methods gave similar results with about 18,000 tons nitrogen in the large June/July intrusion. On a seasonal basis, 40,000 tons of nitrogen could be advected into shelf waters which could result in 200,000 to 400,000 tons carbon production. 相似文献
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空间几何是地理信息区别于一般信息的主要特征,而空间模式规定了空间几何的类型及其相互关系,因而对于地理信息的研究和应用而言,空间模式具有十分重要的意义。 但是目前对空间模式的研究大多停留在如何构造和如何应用,缺少从数学本质上进行的研究。 以几何学、拓扑学为基础,阐述了度量空间、欧氏空间和拓扑空间等数学空间相关概念,以及几何维数、边界和开集等几何对象相关概念的数学定义;结合 IHO《通用海洋测绘数据模型》(S-100)中的空间模式,给出了几何单形和几何复形的数学定义,分析了几何单形、几何复形和几何聚集形之间的关系,认为 S-100 空间模式具有数学严密性、灵活性和可扩展性等特点;接着分析了 S-100 空间模式的构造方法和存储方法;最后认为 IHO 或各成员国应考虑将拓扑对象纳入 S-100 空间模式中。 相似文献
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分析了海洋测绘数据库维护存在的几个问题,提出了调整海洋测绘产品生产体系、建立海洋测绘数据库维护更新机制等设想和建议,以提高海洋测绘数据库的数据质量,更好地为国家经济建设和国防建设服务。 相似文献
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海洋测绘信息元数据标准研究 总被引:2,自引:3,他引:2
介绍了国际标准化组织关于地理信息元数据的定义和国际国内标准化的现状,以及国际海道测量组织关于电子海图元目标的定义;分析了我国关于数字海图的元数据现状。围绕海洋测绘信息元数据涵盖范围、分级分类、描述方法等方面,探讨了建立海洋测绘信息元数据标准体系的必要性和可行的方法。 相似文献