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31.
淮河流域大型水库联合优化调度的动态规划模型解   总被引:6,自引:2,他引:6  
淮河流域暴雨洪水频繁,常常遭遇恶劣雨型的组合。为使大型水库群在大范围暴雨洪水期间综合效益达到最优,采用动态规划模型求解淮河流域大型水库群的联合优化调度问题,利用国产曙光1000巨型计算机的高速度和大容量的优势,解决了优化中的“维数灾”和“网格灾”问题,给出了淮河流域9个大型水库联合优化调度模型极效地提高了防洪水库的利用率。  相似文献   
32.
通过比较分析"十二五"时期新疆自治区土地利用计划指标、供地结构、供地面积、地均GDP以及土地税费等数据变化,总结归纳出土地开发利用现状呈现的基本特征和问题。最后,围绕供给侧结构性改革任务要求,提出"十三五"时期新疆自治区土地开发利用的相关政策建议。  相似文献   
33.
South Korea's seven governmental ministries and agency jointly announced a “Master Plan for Arctic Policy” on December 10, 2013. This represents the state's first comprehensive Arctic policy document. This paper aims to analyze the Korean government's Master Plan from both the legal and policy perspectives, as well as to make constructive comments for its improvement. Environmental changes, the need for scientific research, growing economic optimism about the Arctic region, and political leadership have led South Korea to head north. These four factors form the basis for the Master Plan. This document outlines Korea's vision (to be a reliable and responsible partner in this polar region), three policy goals, four strategies, and thirty-one projects connected to the Arctic region. The formation of the Master Plan has been an opportunity for South Korea to organize and compile all the various Arctic activities independently conducted by governmental ministries and agency. In order to improve South Korea's Arctic policy since the Master Plan, the author recommends that the nation prioritize its projects according to its needs and the feasibility of each project. Prudence is required in the drafting and implementation of Arctic policy to respect Arctic states' sovereignties and sovereign rights over the Arctic areas. Finally, strengthening cooperation with the Arctic states and at Arctic forums is indispensable. In particular, bilateral cooperation is essential for South Korea to perform economic activities such as the exploration for oil and gas.  相似文献   
34.
Huong Ha  Tai-Chee Wong 《GeoJournal》1999,49(3):301-309
The economic reforms or `doi moi' introduced in 1986 have transformed Vietnam's planned economy to a more market-oriented one. Rise in international capital, market liberalisation and greater population mobility have contributed towards a greater concentration of squatters in the city centre, and extended metropolitan development in the fringes of Ho Chi Minh City. Rapid urbanisation and, to a lesser extent, industrialisation have converted large tracts of farmlands to urban use, and greater rural exodus. Such dramatic changes have drawn the city government's attention to face the new challenges. As a very important political and economic centre in the south, Ho Chi Minh City has prepared for itself a new Master Plan, approved in 1997, to provide a legitimate and institutional framework to guide its future spatial development. This paper introduces the background and explains the rationale behind the drafting of the Master Plan, and highlights the constraints that are expected in implementing it. The administrative framework in planning is also examined in terms of its advantages and disadvantages in a planning system with four levels: national, provincial, district and local. Land availability in the city centre, source of funding and technical expertise are all parts and parcels of the challenges in the process of modernising HCMC to accommodate the need of its residents and rapid global change. Ho Chi Minh City's strong relationships with its hinterlands have equally required the planners to look at the planning field using the whole national and regional scenarios. Policy recommendations aimed at improving the implementation capability are finally presented. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
35.
多目标的地质大调查 ——21世纪勘查地球化学的战略选择   总被引:12,自引:0,他引:12  
奚小环 《物探与化探》2007,31(4):283-288
21世纪勘查地球化学面临发展问题.2001~2005年勘查地球化学以国家其基础性公益性地质工作为主导,以经济社会发展需求为动力,以资源与环境并重为方针,实施多目标的地质大调查,取得一系列重要成果,标志勘查地球化学进入全面发展阶段.这是勘查地球化学的战略选择.在现代科学技术取得最新成就起点上,构建理论体系、方法体系和质量体系,在各项工作中采取科学态度和积极有效措施,推动勘查地球化学不断达到新的高度.  相似文献   
36.
《Climate Policy》2013,13(1):87-102
Alternative mechanisms for EU ETS (European Union Emissions Trading Scheme) quota allocations within the Romanian economy were evaluated using a general equilibrium model within a dynamic intertemporal framework. Several distribution rules were simulated based on: the historical emissions, the least-cost approach, and the auctioning scheme with and without a preliminary selection of eligible sectors. We found that the resulting marginal abatement cost in ETS-eligible sectors is only €5.75/tCO2 for reducing pollution by 20.7%. Such a low cost is explained by low energy prices and by substitution possibilities with low carbon content resources (nuclear and hydroelectricity). Including all sectors in the trade creates a more flexible market than in the ETS, since more reduction options are available. The ETS has high feasibility for monitoring. All eligible sectors (except refineries and metallurgy) present the lowest abatement costs in the economy. Auctioning introduces a strong carbon price signal, which reduces emission intensity but creates distortions in terms of trade and worsens the country's energy dependency. Environmental policy has modest macroeconomic results and tends to correct the resources allocation. The strong double dividend obtained under certain circumstances indicates Romania's potential for improving its energy efficiency and carbon intensity.  相似文献   
37.
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38.
随着国土资源信息化建设的快速发展,各地积累了大量的土地利用数据及其变更数据,对这些海量数据的管理和使用,使得多源异构土地利用数据的集成成为当务之急。本文结合建库工作实际,简要介绍了多源异构土地利用数据存在的问题、整合建库的技术方案以及质量控制方案。  相似文献   
39.
Energy system pathways which are projected to deliver minimum possible deployment cost, combined with low Greenhouse Gas (GHG) emissions, are usually considered as ‘no-regrets’ options. However, the question remains whether such energy pathways present ‘no-regrets’ when also considering the wider environmental resource impacts, in particular those on land and water resources. This paper aims to determine whether the energy pathways of the UK’s Carbon Plan are environmental “no-regrets” options, defined in this study as simultaneously exhibiting low impact on land and water services resulting from resource appropriation for energy provision. This is accomplished by estimating the land area and water abstraction required by 2050 under the four pathways of the Carbon Plan with different scenarios for energy crop composition, yield, and power station locations. The outcomes are compared with defined limits for sustainable land appropriation and water abstraction.The results show that of the four Carbon Plan pathways, only the “Higher Renewables, more energy efficiency” pathway is an environmental “no-regrets” option, and that is only if deployment of power stations inland is limited. The study shows that policies for future low-carbon energy systems should be developed with awareness of wider environmental impacts. Failing to do this could lead to a setback in achieving GHG emission reductions goals, because of unforeseen additional competition between the energy sector and demand for land and water services in other sectors.  相似文献   
40.
浅谈山东“十五”地震前兆仪器的运行维护   总被引:1,自引:0,他引:1  
对山东省"十五"前兆仪器的整体运行概况进行分析统计,发现故障多发于无人值守台站,且故障原因多数由于电源、通信、避雷等通用设备导致,结合形变、电磁、流体各学科在日常运行中的典型故障,提出了加强台站人员的责任心及日常性的检查、维护、经验积累是保证前兆仪器稳定运行的基础。  相似文献   
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