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气候变化国家评估报告(Ⅰ):中国气候变化的历史和未来趋势 被引量:1212
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作者 丁一汇 任国玉 +11 位作者 石广玉 宫鹏 郑循华 翟盘茂 张德二 赵宗慈 王绍武 王会军 罗勇 陈德亮 高学杰 戴晓苏 《气候变化研究进展》 CSCD 2006年第1期3-8,F0004,共7页
中国的气候变化与全球变化有相当的一致性,但也存在明显差别。在全球变暖背景下,近100 a 来中国年平均地表气温明显增加,升温幅度比同期全球平均值略高。近100 a和近50 a的降水量变化趋势不明显,但1956年以来出现了微弱增加的趋势。近5... 中国的气候变化与全球变化有相当的一致性,但也存在明显差别。在全球变暖背景下,近100 a 来中国年平均地表气温明显增加,升温幅度比同期全球平均值略高。近100 a和近50 a的降水量变化趋势不明显,但1956年以来出现了微弱增加的趋势。近50 a来中国主要极端天气气候事件的频率和强度也出现了明显的变化。研究表明,中国的CO2年排放量呈不断增加趋势,温室气体正辐射强迫的总和是造成气候变暖的主要原因。对21世纪气候变化趋势做出的预测表明:未来20-100 a,中国地表气温增加明显,降水量也呈增加趋势。 展开更多
关键词 中国气候变化 极端事件 温室气体 气溶胶 辐射强迫 气候预估
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FPGA单粒子翻转事件在轨探测研究 被引量:18
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作者 侯建文 张爱兵 +1 位作者 郑香脂 余庆龙 《宇航学报》 EI CAS CSCD 北大核心 2014年第4期454-458,共5页
中国遥感卫星上的单粒子探测器对某种400万门FPGA和60万门FPGA进行在轨单粒子翻转探测。文中给出了单粒子翻转探测器的基本组成及单粒子翻转的监测方法,并给出了采用模拟量描述器件翻转次数的设计思路。在轨测试期间,单粒子探测器成功... 中国遥感卫星上的单粒子探测器对某种400万门FPGA和60万门FPGA进行在轨单粒子翻转探测。文中给出了单粒子翻转探测器的基本组成及单粒子翻转的监测方法,并给出了采用模拟量描述器件翻转次数的设计思路。在轨测试期间,单粒子探测器成功的对被测器件进行了在轨单粒子翻转监测,文中给出了两个被测器件的翻转次数统计和翻转类型统计,依据轨道根数获得了翻转事件的空间分布,并对两个被测芯片的翻转事件的差异进行了分析。 展开更多
关键词 FPGA 单粒子翻转 在轨探测 空间环境
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The Business of Managing Risk and Network Security:An Exploration of Knowledge Transfer Issues within the Context of Data Security and Countermeasure Trade Offs
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作者 Jim MorrisVice President(Trident Data Systems 12701 Fairlakes Circle.Suite 350 Fairfax,VA22033 USA)Jim SnaithPrincipal Lecturer In Business Information Systems(Area of Finance Accounting and Business Information SystemsSouth Bank University Business Schoo 《计算机工程》 CAS CSCD 北大核心 1996年第S1期68-81,共14页
The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as int... The contemporary environment within which command,control,communications,computers and intelligence (C4I platforms exist, have a number of characteristics. These characteristics may be most obviously identified as interconnectivity, international networking, speed of data transfer, the compact nature of electronic information and rapidly changing technology. Information security professionals employ a variety of approaches in order to counter risks within this complex and fluid environment. The gamut of potential security activities ranges form access control through a variety of auditing techniques to secure data communications. This field is broad and well documented. Indeed, the discipline of network risk management and data security is both well developed and sophisticated.This paper addresses twin themes:i.The fundamental issue of the method by which specific approaches are employed. This is a precursor to the adoption of an eventual strategy.ii.The crucial issues revolving around the 展开更多
关键词 VALUE - The perceived or intrinsic WORTH of AN ASSET based on purchase or development COSTS operations COSTS WORTH of information processed recovery expenes or any combination thereof. VALUE is relative to point- of- view.Threat- AN cvent
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On the Formative Factors of Urban Narrative Space 被引量:1
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作者 Li Peng Zhang Nan 《学术界》 CSSCI 北大核心 2015年第9期275-279,共5页
With the continuous development of society,the urban space has already met the basic functional needs of the people.As the crystallization of the ideology of mankind and the social development,the urban space exerts a... With the continuous development of society,the urban space has already met the basic functional needs of the people.As the crystallization of the ideology of mankind and the social development,the urban space exerts an effect on the people on both the material level and the spiritual level.The urban space inherits the urban culture and influences people’s feelings,and the proper narrative space can meet the increasing emotional needs.This paper analyzes the three formative factors of the urban narrative space—the temporal factor,the spatial factor and the diversified event factor,showing the readers a clearer narrative space and laying foundation for the further study on narrative space theory. 展开更多
关键词 城市空间 形成因素 社会发展 功能需求 城市文化 空间因素 空间理论 空间美
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