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排序方式: 共有247条查询结果,搜索用时 15 毫秒
1.
南水北调石家庄受水区地下水压采方案探讨   总被引:2,自引:0,他引:2  
南水北调中线石家庄受水区水资源匮乏严重,由于连年超采地下水已引发了严重的环境地质问题。现对南水北调中线石家庄受水区地下水压采方案进行探讨,通过工程措施、管理措施和相关法规、办法的制定,开源与节流并举,使该区域水资源能够支撑区域社会、经济、环境的可持续发展。  相似文献   
2.
湘鄂赣苏区商业述评   总被引:1,自引:0,他引:1  
商业工作是湘鄂赣苏区各项建设中的重要一环。由于国民党政权的烧杀政策和经济封锁,苏区建立前后的商业贸易基本停滞。为改变这种被动局面,党和苏维埃政府采取各种措施,使苏区的商业工作取得巨大的成绩,在打破国民党军队的经济封锁、活跃苏区经济、支援革命战争方面、保障群众生活作出了重大贡献。  相似文献   
3.
综合分压配气和流量配气的特点和优势,设计了基于分压配气和流量配气原理的自动化配气控制系统,用于I类、II类隔爆型设备(d)和III类可燃性粉尘环境外壳保型设备(tD)的耐爆和传爆试验。经试验测试与比对:该系统可靠性、精确度、稳定性和重复性方面均满足GB 3836.2-2010防爆试验所规定的要求,并具有节省试验时间和试验气源的优点。  相似文献   
4.
南方碳酸盐岩复杂地区的地震工作经历了长期艰难曲折的道路,其中异常判别的经验教训极为深刻。本文从地震异常分析入手,揭示其实质,寻求问题的关键,探讨解决的办法,介绍高分辨率地震方法技术,展示高分辨率地震新成果,以得出有意义的结论和建议。  相似文献   
5.
The Jackfish Bay Remedial Action Plan is the first of Lake Superior's Areas of Concern (AOCs) to consider recognition as an Area in Recovery (AiR). As a result of a high degree of complexity and uncertainty, ecosystem recovery in Jackfish Bay has been determined using a combination of regulatory policies and scientific evidence and extensive public and expert-based decision making. As a result, the conceptualization of the AiR status in Jackfish Bay has been developed with the adaptive management and the ecosystem approach, which provide the basic principles of assessing, monitoring, and managing the Area of Concern. To determine the status of beneficial use impairments caused by effluent from the Terrace Bay Pulp Inc., three public advisory committees—an academic panel of experts, a government technical review committee, and the Jackfish Bay Public Area in Recovery Review Committee (PARRC)—reviewed relevant scientific data and documents, including peer-reviewed publications, to assess changes in pollution levels in Jackfish Bay and improvements to aquatic, biotic, and benthic environments of the bay. The public decision-making process concluded with recommendations by the PARRC to develop a systematic monitoring program so that the ecosystem recovery process in the bay could be assessed on a continued basis, leading to its eventual delisting as an AOC. The entire process provides an example of blending science and public policies for remediation of a degraded ecosystem on the Great Lakes.  相似文献   
6.
针对民族地区高等院校计算机教育的特点与面临的困难,提出相应的解决对策和改革方向。探讨如何构建现代人才素质需求与地方民族特色相结合的计算机教学体系,从而促进民族地区计算机人才的培养。  相似文献   
7.
The exurbanization process, particularly rural residential development, is reducing the amount of roadless areas and remote habitat across the nation, with implications for biodiversity and ecosystem integrity of parks and protected areas. The need for connecting protected areas via existing habitat centers, or relatively undisturbed core areas, is greater than ever as exurbanization expands. Our objective was to make use of nationally available data sets on roads as well as information derived from satellite imagery, including impervious cover of the built environment and forest canopy density, to identify core habitat of the northeastern and mid-Atlantic USA. The identified core habitat areas, which covered 73,730 km2 across 1177 discrete units, were stratified in terms of land ownership and management, and then analyzed in a landscape context using connectivity metrics derived from graph theory. The connectivity analysis made use of a suitability surface, derived from the land cover information, which approximated the costs incurred by hypothetical animals traversing the landscape. We show that protected areas are frequently identified as core habitat but are typically isolated, albeit sometimes buffered by adjacent multi-use lands (such as state or national forests). Over one third of the core habitat we identified has no protection, and another 42% is subject to motorized recreation or timber extraction. We provide maps showing the relative importance of core habitat areas for potentially connecting existing protected areas, and also provide an example of the vulnerability of connectivity to projected future residential development around one greater park ecosystem.  相似文献   
8.
The protection of patients’ health information is a very important issue in the information age. Health Insurance Portability and Accountability Act (HIPAA) of privacy and security regulations are two crucial provisions in the protection of healthcare privacy, especially electronic medical information. For the quality and efficiency of the electronic services, it is necessary to construct better performance for the user and the trusted party. Based on elliptic curve cryptography (ECC) and complying with HIPAA regulations, this article presents an efficient key management scheme to facilitate inter-operations among the applied cryptographic mechanisms. In addition, the proposed scheme can achieve the complete functionality which includes: (1) a dictionary of key tables is not required for users and other units; (2) users can freely choose their own passwords; (3) users can freely update their passwords after the registration phase; (4) the computational cost is very low for users and the trusted center or server; (5) users are able to access their individual medical information through the authorization process; (6) case of consent exceptions intended to facilitate emergency applications or other possible exceptions can also be dealt with easier.  相似文献   
9.
针对在同一场景下获取的体育运动视频,提出了一种基于全局运动补偿及运动前景区域信息的体育运动视频合成方法。首先,对待合成视频,通过全局运动估计与补偿,将相邻帧在空间上对齐到当前帧。通过计算帧差,得到当前帧中的运动前景区域信息。然后根据两段待合成视频之间背景的相似性,计算并修正全局运动参数,确定待合成对应帧之间的位置关系。最后,依据已经获得的运动前景区域信息,生成合成帧。实验结果表明,该方法可自动合成在同一场景中获得的有相似动态背景的体育视频,保持了前景与背景的清晰度,能清晰地显示运动员动作的差异。  相似文献   
10.
Linux在保护模式下的中断处理分析   总被引:1,自引:0,他引:1  
该文以80x86保护模式下的中断处理方法为基础,针对Linux在实时嵌入式系统中的具体应用,阐述Linux在保护模式下的中断及其中断响应处理过程,深入地分析Linux下的中断描述符初始化过程及中断处理程序的实现,最后通过Linux可加载内核模块编程对所作的分析进行验证。  相似文献   
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