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71.
本文结合农业气象情报服务工作实践,阐述了如何利用Access数据库系统和VB6.0实现对农情资料传输、添加和分析系统.  相似文献   
72.
给出一种用RAM扩充程序存贮器的方法,以及具体的硬件线路。这种简便实用的方法可为用户提供一种根据需要自行修改或编写应用程序的环境.  相似文献   
73.
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   
74.
The European Union’s Integrated Maritime Policy is intended in part to co-ordinate sectoral policies, to achieve joined-up thinking and action and overcome the inconsistency between policy approaches that has led to the degradation of European seas. An integrated governance would be relatively straight-forward if the different interests and actors were operating on the basis of shared values, but they are not. While the fisheries sector, whether large or small-scale, is driven by a commercial imperative which tends towards the greatest extraction of the resource possible, environmentalists would champion the removal of all human impacts, other than redress activity, as the optimum state for the ecosystem. However, the greatest impediment to an integrated approach is the failure to subject the EU’s Common Fisheries Policy to the objectives of the Integrated Maritime Policy. Instead, all decisions concerning fisheries will continue to be made in accordance with the Fisheries Regulation which demands exploitation of the fragile resource. Attention needs to be given to how EU fisheries policy is to acquire values beyond that of commercial extraction for immediate economic benefit so that it may cohere with objectives of the Integrated Maritime Policy and aid the regeneration of the seas.  相似文献   
75.
在Microsoft Access 2000中编辑制作的华南花岗岩数据库,由24张表格和相应的表单、部分查询组成,可以方便地实现花岗岩数据的管理和GeoKit、Mapgis等软件对数据的引用处理;界面友好,操作简单,是花岗岩类数据收录、管理与综合分析的有用工具.  相似文献   
76.
This paper describes the historical roots of an ongoing wildlife management dilemma involving decreasing opportunities for elk management via public hunting on private land in the context of an expanding elk presence on private land in southwest Montana. Our main focus is on the role of private ranchland in elk ecology, and the ability of land owners to set elk migration in new directions through cumulative decisions about hunting and tolerating elk. This takes elk management, traditionally the purview of the state, out of administrative control. We document connections between the region’s historical and emerging land tenure patterns, and analyze associated changes in hunter access. Elk numbers expanded rapidly in the Upper Yellowstone Valley at a moment of significant transition in ranchland tenure. New owners more interested in natural amenities than in livestock production encouraged the elk and discouraged hunting. This reinforced the spread of elk, and further weakened the ability of the state and other ranchers to manage elk (which interfere with livestock production in numerous ways). Though elk and cattle use the landscape in similar ways, elk became more effective agents of landscape change in a reflexive relationship with ideas of land that stress natural amenities over production.  相似文献   
77.
Marine genetic resources are a subject of a growing body of research and development activities, as demonstrated by the abundance of marine patented genes reported in GenBank. Given the lack of a comprehensive legal regime for the management of marine genetic resources in areas beyond national jurisdiction, the General Assembly of the United Nations met in 2006 to discuss whether there are regulatory or governance gaps and how to address them. Besides the crystallization of the different political positions, the process is now advancing towards making a decision about whether to develop an international instrument under the United Nations Convention on the Law of the Sea (UNCLOS) for the conservation and sustainable use of marine biological diversity, within which the regulation of access to genetic resources and the sharing of benefits from their utilization has emerged as an in-dissociable issue. In order to propose concrete options to be considered for the establishment of a legal framework addressing these issues, policy-makers need to better understand the feasibility, the costs and the modalities of scientific activities undertaken, together with the actual level of commercialization of new products. They also need to be aware of the already advanced practices in place within the scientific community, especially regarding sharing of non-monetary benefits. This paper particularly highlights and discusses practical scenarios to advance in the international process, based on the approaches adopted in other regional and international regimes for the management of genetic resources and on the best practices developed within the scientific community.  相似文献   
78.
This study analyzed information gathered from 200 date palm households in the mountainous Panjgur District of Balochistan in Pakistan with the aim of determining date farmers' access to and satisfaction with agricultural extension services. Information was collected through a structured questionnaire survey, group discussions and semi- structured personal interviews. The findings of the analysis revealed very poor access to extension services. The results of logistic regression analysis identified five variables out of six which significantly influence date farmers' access to extension services: household bead's age, household bead's literacy, number of date palm trees owned, mostly inherited date palm trees, and percentage of dead date palm trees. The overwhelming majority of farmers were dissatisfied with all three main types of extension services being provided by public extension officials. Explanations for this as well as for associations between access to extension services and the six independent variables are provided. Important policy conclusions are drawn based on the findings.  相似文献   
79.
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   
80.
Knowing the patterns of marine resource exploitation and seafood trade may help countries to design their future strategic plans and development policies. To fully understand these patterns, it is necessary to identify where the benefits accumulate, how balanced the arrangements are, and how the pattern is evolving over time. Here the flow of global seafood was traced from locations of capture or production to their countries of consumption using novel approaches and databases. Results indicate an increasing dominance of Asian fleets by the volume of catch from the 1950s to the 2010s, including fishing in the high seas. The majority of landings were by high-income countries’ fishing fleets in their own waters in the 1950s but this pattern was greatly altered by the 2010s, with more equality in landings volume and value by fleets representing different income levels. Results also show that the higher the income of a country, the more valuable seafood it imports compared to its exports and vice versa. In theory, this implies that the lower income countries are exporting high value seafood in part to achieve the broader goal of ending poverty, while achieving the food security goal by retaining and importing lower value seafood. In the context of access arrangements between developed and developing countries, the results allow insights into the consequences of these shifting sources of income may have for goals such as poverty reduction and food security.  相似文献   
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