首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   98篇
  免费   6篇
  国内免费   6篇
测绘学   22篇
大气科学   15篇
地球物理   13篇
地质学   30篇
海洋学   17篇
天文学   5篇
综合类   1篇
自然地理   7篇
  2021年   1篇
  2020年   1篇
  2019年   2篇
  2018年   1篇
  2017年   2篇
  2016年   8篇
  2015年   3篇
  2014年   7篇
  2013年   5篇
  2012年   4篇
  2011年   14篇
  2010年   5篇
  2009年   9篇
  2008年   7篇
  2007年   6篇
  2006年   8篇
  2005年   5篇
  2004年   2篇
  2003年   3篇
  2002年   6篇
  2001年   6篇
  2000年   3篇
  1997年   1篇
  1995年   1篇
排序方式: 共有110条查询结果,搜索用时 15 毫秒
31.
The world's largest no-take Marine Protected Area in Chagos is examined in light of the Convention on Biological Diversity's provisions on Access and Benefit Sharing, as well as terrestrial experiences with fortress conservation. It is acknowledged that this closure presents a unique opportunity to preserve an ecologically 'pristine' area. However, the means by which the political process unfolded are brought into question. In particular, the fact that the UK proceeded with designating the area whilst the European Court of Human Rights was deliberating the right of native Chagossians to return to the island is questioned. In addition it is argued that the scale of the area poses significant management and enforcement challenges, which are not necessarily taken into consideration in the rush for large, no-take Marine Protected Areas.  相似文献   
32.
Abstract

The emergence of Cloud Computing technologies brings a new information infrastructure to users. Providing geoprocessing functions in Cloud Computing platforms can bring scalable, on-demand, and cost–effective geoprocessing services to geospatial users. This paper provides a comparative analysis of geoprocessing in Cloud Computing platforms – Microsoft Windows Azure and Google App Engine. The analysis compares differences in the data storage, architecture model, and development environment based on the experience to develop geoprocessing services in the two Cloud Computing platforms; emphasizes the importance of virtualization; recommends applications of hybrid geoprocessing Clouds, and suggests an interoperable solution on geoprocessing Cloud services. The comparison allows one to selectively utilize Cloud Computing platforms or hybrid Cloud pattern, once it is understood that the current development of geoprocessing Cloud services is restricted to specific Cloud Computing platforms with certain kinds of technologies. The performance evaluation is also performed over geoprocessing services deployed in public Cloud platforms. The tested services are developed using geoprocessing algorithms from different vendors, GeoSurf and Java Topology Suite. The evaluation results provide a valuable reference on providing elastic and cost-effective geoprocessing Cloud services.  相似文献   
33.
震后桥梁结构震害快速评估能够为地震应急救援提供重要参考信息,对减灾工作具有重要价值。为了快速准确地评估遭受地震影响梁式桥的破坏状态,使梁式桥震害评估方法在地震应急中发挥更大作用,基于统计回归模型、神经网络模型和推断模型等三种梁式桥震害评估模型,采用VC++6.0及Access2003数据库软件开发了有关评估软件,并以桥梁震害资料为算例验证了软件的可靠性。  相似文献   
34.
Astrometric and photometric observations of major planets, their satellites and asteroids have been made with the 26-in. refractor of the Pulkovo observatory during the period from 1995 to 2006. The CCD (ST6) and photographic observations were carried out. Accurate relative position of satellites of Jupiter and Saturn have been derived. The positions of Saturn have been calculated using the theoretically predicted coordinates of satellites relative to the planet without measurements of the photographic images of the planet. Also the observations of Hale-Bopp comet and Mercury transit have been made. The 26-in. refractor has been included into the international campaign PHEMU-2003: photometric CCD observations of mutual occultations and eclipses of Galilean satellites. The light curves of the events have been obtained and parameters of the events have been determined.  相似文献   
35.
动态分段思想在公路地理信息系统中的实现   总被引:7,自引:0,他引:7  
动态分段是一种全新的线性特征的动态分析技术,可以有效地解决公路线性特征的动态分析问题,实现公路图形和属性数据间的双向动态可视化查询。文章以Arc/Info为代表,分析了动态分段技术的原理,结合VB6.0、MapObjects2.2和Access,初步介绍了公路GIS中动态分段的数据结构与算法,并探讨了如何实现公路GIS的过程。  相似文献   
36.
Microsoft SQL Server 2000在天津市地震前兆台网中心的应用   总被引:4,自引:0,他引:4  
主要介绍了《天津市地震前兆台网管理软件》的数据库管理功能及其在前兆台网中心的重要作用,VB管理数字化前兆数据库的关键技术、HTTP方式访问数据库的方法以及地下流体月报表打印源码实例等。  相似文献   
37.
介绍了Geoway ImageStation软件的网络化生产功能及其在镶嵌线编辑成图中应用的一些实用技巧,为使用该软件进行影像图制作的同仁提供参考.  相似文献   
38.
The Kimberley coast in Australia's far north-west is the traditional country and home of a number of Indigenous groups and hosts some of the country's richest cultural heritage, most spectacular rock art, scenery and wildlife, making it an attractive tourism destination. A growing expedition cruise industry provides the main means of visitor access to remote coastal sites and offers excursions to shore-based attractions in what are mostly Aboriginal Reserve lands. In light of concerns about environmental and cultural site impacts resulting from increasing visitor numbers, this study examined biophysical site impacts along access trails to shore-based attractions and used qualitative methods to ascertain cultural impacts. The synthesis of the findings highlights that cultural concerns arising from visitor access without having sought traditional owner consent for such access, combined with a lack of traditional owner involvement in the planning, management or running of visitor activities, overshadow currently low environmental impacts of onshore expedition cruise activities. To overcome the continuing impasse regarding the issue of unsanctioned visitor access, the Kimberley urgently needs a coordinated approach by key stakeholders and the traditional owners which recognises and acknowledges the historical context. Such a process would facilitate tourism activities to become culturally sustainable.  相似文献   
39.
The imposition of exclusive statutory real property rights in or near pastoralists’ areas and their migration corridors permanently excludes and extinguishes pastoralist rights to mobility and access to required resources. Seasonal interactions with non-pastoralist land use actors often occur during pastoralist migrations between rangelands and highlands or dry season grazing areas. In an embedded case study in Northern Kenya, in which interviews based on semi-structured questionnaires were held with pastoralists and non-pastoralists, we investigated how non-pastoralist land use actors manage encounters with migrating pastoralists within the context of the Land Administration system. We found that the majority of non-pastoralist land use actors encounter migrating pastoralists during distinct periods. Most never allow herders access to privately owned land. A small proportion allow access and make temporary verbal or written access agreements containing provisions on grazing fees, grazing regulations and rules to protect private property. The majority of non-pastoralists are unwilling to have access arrangements formalized. We argue that land rights adjudication should identify and confer all existing land rights to all users to avoid obstruction or renegotiation for access, and recommend the inclusion of pastoralists’ access rights as real property rights in the Land Administration system.  相似文献   
40.
在随着2000国家大地坐标系在全国不断推广与应用,将ITRF2000框架下的坐标转换到CGCS2000框架时,需先转换到ITRF1997框架下。本文采用布尔沙-沃尔夫模型对基于不同基准的两框架之间进行坐标转换,设计了七参数求解程序,并通过实例分析验证其准确性和可靠性。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号