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61.
本文应用VPN组网技术,全省各地的下属单位通过互联网建立与省局局域网虚拟专网隧道,通过配置防火墙的IP访问控制,获取访问省局局域网中的学位论文服务器的指定IP地址范围和必要权限,查阅相关学位论文,有助于开展各项科学研究工作。  相似文献   
62.
“数字城市”的空间数据库设计方法研究   总被引:1,自引:0,他引:1  
万剑华  刘娜  马张宝  孟慧 《测绘科学》2006,31(6):107-108
本文简单介绍了“数字城市”的背景和理论基础,并对常用的Access、SQL Server、Oracle数据库进行对比分析与研究,总结了各自的优缺点;分别从数据库的结构设计、数据库的功能设计、数据库的界面设计、基础数据库的建立等方面提出了“数字城市”的数据库的设计与建设方案,并成功运用在“数字东营”的数据库建设中。  相似文献   
63.
The Marine and Coastal Access Bill, when it becomes law, may well be considered a welcome addition to the legislation protecting the marine coastal environment. It is argued, however, in this paper that the Bill could have addressed a number of issues including the matter of shipowners’ privileges, locus standi, the designation and setting up of an environmental fund, and the difficulties associated with places of refuge for vessels in distress.  相似文献   
64.
65.
分析了动态网页访问控制的现状和需求,提出了一种动态网页细粒度策略自适应访问控制模型(FPAAC),并在开发的模拟系统中进行了验证。  相似文献   
66.
南岭地区锡多金属矿床空间数据库建设是国家地质调查主管部门和南岭地区新一轮地质勘查、矿产开发的需要.数据库在Microsoft Access 2000和Mapgis软件中编辑制作,包括ACCESS(.mdb)和MAPGIS点文件(*.WT)两种格式的文件,由矿床基本情况与矿区地质情况两张基本表格和相应的表单、查询组成,矿...  相似文献   
67.
Roman Grynberg   《Marine Policy》2003,27(6):499-511
The paper considers the WTO negotiations on fisheries subsidies and the implications that envisaged disciplines will have on coastal developing countries. This is considered in relation to fisheries access agreements in the Central and Western Pacific where several least developed but resource rich island states such as Kiribati and Tuvalu are highly exposed to the risks associated with new WTO fisheries subsidies disciplines that do not consider their particular vulnerabilities. The paper considers some of the issues that coastal developing countries should incorporate into their emerging negotiating positions at the WTO. State-to-Sate fisheries access agreements which are often highly subsidised but where fishing vessel owners pay the equivalent of lump sum tax are paradoxically, the least distortionary and damaging to the environment. Strategies for managing the possible new disciplines are considered.  相似文献   
68.
随着空间定位技术的普及,不同空间直角坐标系间的转换过程中经常遇到问题不易被解决。本文首先介绍了不同空间直角坐标系间转换时广泛使用的布尔沙转换模型并阐述了七参数求解的过程,然后结合ACCESS中的表、窗体和宏,利用VBA实现了基于布尔沙转换模型的七参数计算程序,并结合实例对所编写的程序加以验证,保证其结果的可靠性。  相似文献   
69.
Globally, small-scale fisheries are critical for livelihoods and food security yet face increasing uncertainty and variability from processes such as overfishing, globalization, and climate change. Enhancing the number of options for human response through increased access to marine resources, diverse livelihood approaches, and generalist fishing strategies may attenuate the negative effects of change and disturbance. My research explores the relative importance of diversification strategies for achieving resilient small-scale fishing communities and cooperatives of Baja California Sur, Mexico. Specifically, interview data and long-term catch and economic data were used to develop an economic metric of resilience, in addition to income diversification indices, for fishing cooperatives. Fishing cooperative characteristics and environmental conditions were then evaluated as possible predictors of cooperatives’ relative ability to diversify. I found that while diversification was important for risk mitigation and stabilizing income, the ability of cooperatives to specialize during favorable conditions may be important for poverty reduction and wealth accumulation. Thus, the flexibility to move across fishing strategies given changing environmental conditions is important for the adaptive capacity of small-scale fishing cooperatives. My findings will contribute to a better understanding of the institutional arrangements that promote a resilient small-scale fishery, and therefore, will be invaluable for practitioners of small-scale fisheries.  相似文献   
70.
利用Access97和VB6的ADO开发工程勘察数据库   总被引:3,自引:0,他引:3  
根据开发工程勘察数据库的经历,介绍了利用YB6的ADO和Access97开发工程勘察数据库的步骤、方法和技巧,以及开发过程中可能遇到的问题和解决办法。  相似文献   
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