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41.
Drought is recognized as a major issue in the EU, particularly in the Mediterranean region, posing risks to the environment as well as to local and regional economies. The EU policy on water management is continuously evolving, particularly in relation to water scarcity and drought. Starting with the Water Framework Directive (2000/60/EC), which sets the general policy framework for water management across the EU, the EC Communication on Water Scarcity and Drought COM(2007) 414 final set the priorities for managing water scarcity and drought risks. Three follow-up reports (COM(2008) 875 final, COM(2010) 228 final and COM(2011) 133) highlighted achievements and yearly progress within the context of the implementation of the Water Framework Directive, whereas guidance has further been provided through the issue of Technical Reports (e.g. the EC Water Scarcity Drafting Group Technical Report 2008–023 on Drought Management, Including agricultural, drought indicators and climate change aspects). The 2012 EU Water Review (“Blue Print for Safeguarding European Waters” will assess achievements and identify further requirements towards long-term sustainable water use across the EU. However, a harmonized approach on drought risk management at the EU level is still lacking, whereas drought risk in several countries and regions has not been yet fully integrated in water management and relevant sectoral policies.This paper focuses on a proposed paradigm shift from crisis to risk management, which is currently gaining ground as a means of reducing societal vulnerability to droughts. The paper underlines the importance of engaging into risk assessment and management practices and identifies policy gaps and requirements for further improvement of the drought management policy framework at all levels of governance: at the EU, at the national and at the river basin and regional levels.  相似文献   
42.
判决反馈自适应滤波应用于CDMA系统中的单频干扰抑制   总被引:1,自引:0,他引:1  
针对扩频接收机中窄带干扰抑制中已有结构和算法的优缺点,提出一种在滤波器输入和权值修正中均利用判决值的判决反馈方案,并对常规、采用软判决和采用硬判决三种情况的单边预测型结构和常规最小均方误差(LMS)算法、可变步长LMS(VSS)算法和变步长变动量因子LMS(VSVMS)算法三种算法进行了计算机模拟。结果表明,此判决反馈方案对抑制单频干扰在性能上比已有结构有明显改进,且软判决比硬判决性能略优,算法以  相似文献   
43.
This article reviews the influence of two specific European Union (EU) laws, the Birds and Habitats Directives, on the choice of national policy instruments by Member States. Both Directives leave the choice for policy instruments to manage the sites designated under the Directives to the Member States. Using path dependency as a leading concept, this article analyses the continuity or changes in policy instruments due to the implementation of the Directives in 15 countries. This article shows that the tendency to use existing instruments to implement EU policy is limited, as in almost all countries new instruments were developed. Yet, states do tend to choose instruments from their predominant policy instrument mix and preferred implementation style to address the management requirements of the Directives. Additionally, in Central and Eastern European countries where the implementation of EU policy coincided with a process of transition to a market economy, new instruments were introduced outside the existing implementation style. The introduction of new policy instruments is the result of historical turns, domestic pressure and a shift to new modes of governance. National case studies are needed to shed more light on the interaction between EU policy and domestic factors during the process of instrument choice.  相似文献   
44.
杜丽冰 《环境技术》1998,16(3):30-34
提出一种三值滤波器输入和权值修正中均采用判决值的非线性判决反馈干扰抑制器,用于抑制CADM中的单频干扰。  相似文献   
45.
张亮  朱珊 《环境技术》2011,32(1):55-58
本文详细解读了GMW 3205:2000汽车内饰材料中气味散发测试方法以及SAE J1351绝缘材料气味散发测试方法之间的差异.介绍了汽车内饰件材料气味测试原理.以及气味试验的定义与实际使用中的意义等方面对GMW 3205:2000和SAE J1351气味测试标准进行差异分析.  相似文献   
46.
2000年中国大陆地震灾害评述   总被引:3,自引:2,他引:3  
在列出2000年中国5级以上地震目录的基础上,结合有关省(自治区-直辖市)地震局的地震灾害评估资料,总结了2000年中国大陆地震灾害的主要数据和特性。最后,对1990-2000年与1980-1989年两个时间段中国大陆地震灾害的相应数据和特性进行了比较。  相似文献   
47.
杜丽冰 《环境技术》1998,16(1):29-32
在分析多区蜂窝CDMA系统干扰的基础上,提出了开,闭环结合的功控方式,要求和以载干比(CIR)为基础的功控算法,从而抑制干扰,改善系统性能,增加系统容量。  相似文献   
48.
Abstract:  For more than 10 years, ecologists have been discussing the concept of ecosystem engineering (i.e., nontrophic interactions of an organism that alters the physical state of its environment and affects other species). In conservation biology, the functional role of species is of interest because persistence of some species may be necessary for maintaining an entire assemblage with many threatened species. The great capricorn ( Cerambyx cerdo ), an endangered beetle listed in the European Union's Habitats Directive, has suffered a dramatic decline in the number of populations and in population sizes in Central Europe over the last century. The damage caused by C. cerdo larvae on sound oak trees has considerable effects on the physiological characteristics of these trees. We investigated the impacts of these effects on the species richness and heterogeneity of the saproxylic beetle assemblage on oaks. We compared the catches made with flight interception traps on 10 oaks colonized and 10 oaks uncolonized by C. cerdo in a study area in Lower Saxony (Germany). Our results revealed a significantly more species-rich assemblage on the trees colonized by C. cerdo . Colonized trees also harbored more red-listed beetle species. Our results suggest that an endangered beetle species can alter its own habitat to create favorable habitat conditions for other threatened beetle species. Efforts to preserve C. cerdo therefore have a positive effect on an entire assemblage of insects, including other highly endangered species. On the basis of the impact C. cerdo seems to have on the saproxylic beetle assemblage, reintroductions might be considered in regions where the species has become extinct.  相似文献   
49.
2000年全球重大自然灾害概述   总被引:2,自引:1,他引:2  
2000年是全球自然灾害经济损失较为一般的年份。根据收集到的全球自然灾害记录的数据,客观地对全球主要自然灾害的特征和分布特点进行了分析,并对其成因进行了探讨.  相似文献   
50.
本文以Excel 2000统计学生全班成绩表为例,介绍基本的Excel输入资料、统计成绩(计算总分、计算平均分、计算最高分最低分、排列名次)、制作图表等功能.  相似文献   
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