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排序方式: 共有1567条查询结果,搜索用时 15 毫秒
91.
安洁 《科技情报开发与经济》2012,22(16):118-119
简述了绿色环保建筑的基本概念及钢结构住宅的绿色环保性能,介绍了我国钢结构建筑的现状,对我国未来绿色环保建筑的发展进行了简要的探讨。 相似文献
92.
利用国家知识产权局互联网检索数据库SooPat专利数据库,采集2004年1月1日至2013年12月31日期间的LED驱动电源技术专利文献,建立LED驱动电源专利数据库.再选择国家知识产权局专利信息服务平台分析系统分别从专利申请区域分布、IPC技术类别分布和专利申请人分布等方面,对LED驱动电源技术专利进行了深入的分析,提出了发展广东省LED驱动电源技术的专利策略. 相似文献
93.
以CNKI电子技术及信息技术数据库所收录的(2001-2009)1516篇文章为研究对象,以探讨量性与质性的内容分析,探究元数据(Metadata)在图书情报学科的研究发展。 相似文献
94.
21世纪科技的发展将对人类的生存空间、物质进步产生重大的影响,人类只有积极地应对科技,才能实现人类的全面发展。本文就此问题展开讨论。 相似文献
95.
利用1951年9月~2010年8月宜昌站逐日气象资料,采用气候趋势系数、5a滑动平均法、累积距平和一元线性回归法对宜昌市近59年来的气候变化趋势特征进行了诊断分析,结果表明:宜昌市的年平均气温呈现上升趋势,年平均最低气温的上升速率高于年平均最高气温的上升速率,导致年平均日较差呈现下降的趋势;在季节变化上,除了夏季,其他季节都呈升高趋势,其中春季的上升趋势最为显著.年降水量呈现略微增加的趋势,冬季增加趋势较为显著.该成果对进一步研究和预测宜昌市的气候变化有着重要意义. 相似文献
96.
伍国正 《海南大学学报(自然科学版)》2011,29(3):246-251
通过对2010年上海世博会中国馆的形象特征、设计理念、文化内涵和美学特征的解读和分析,论述了中国馆体现在地域性、民族性和时代性等方面的建筑美学意义,突出了中国馆多元丰富性的建筑美学内涵与建筑艺术的文化价值和审美价值.指出建筑的形式和风格在适应自然条件、社会和人文环境等方面的重要作用;建筑本土化意味着地域性民族文化传统、... 相似文献
97.
LIU Yu * CAI QiuFang SONG HuiMing AN ZhiSheng & Hans W. LINDERHOLM The State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Department of Environmental Science Technology School of Human Settlements Civil Engineering Xi’an Jiaotong University Xi’an Graduate University of Chinese Academy of Sciences Beijing Regional Climate Group Department of Earth Sciences... 《科学通报(英文版)》2011,(Z2):2986-2994
Amplitudes, rates, periodicities, causes and future trends of temperature variations based on tree rings for the past 2485 years on the central-eastern Tibetan Plateau were analyzed. The results showed that extreme climatic events on the Plateau, such as the Medieval Warm Period, Little Ice Age and 20th Century Warming appeared synchronously with those in other places worldwide. The largest amplitude and rate of temperature change occurred during the Eastern Jin Event (343-425 AD), and not in the late 20th century. There were significant cycles of 1324 a, 800 a, 199 a, 110 a and 2-3 a in the 2485-year temperature series. The 1324 a, 800 a, 199 a and 110 a cycles are associated with solar activity, which greatly affects the Earth surface temperature. The long-term trends (>1000 a) of temperature were controlled by the millennium-scale cycle, and amplitudes were dominated by multi-century cycles. Moreover, cold intervals corresponded to sunspot minimums. The prediction indicated that the temperature will decrease in the future until to 2068 AD and then increase again. 相似文献
98.
张丽明 《科技情报开发与经济》2011,21(26):106-108
以郑州大学科技查新工作站为例,分析了2008—2010年郑州大学科技查新工作情况,探讨了科技查新工作未来发展的趋势,提出了进一步完善科技查新工作的对策。 相似文献
99.
Exploration for oil and deep gas in northern Songliao Basin,complex rift basin—Hailaer Basin,and Yi-Shu Graben in peripheral basin has technical challenge.Researches on supporting technology including seismic acquisition,processing and interpretation,logging and drilling are performed to establish high resolution 3D seismic technology for lithologic reservoir,deep volcanic rock and complex rift basin,reservoir evaluation and stimulation technology for low permeability reservoir,volcanic reservoir and complex rift reservoir,and drilling technology for deep volcanic rock,providing technical support for reserves increase in northern Songliao Basin,large gas reservoirs discovery in deep volcanic rock and exploration progress in complex rift basin.Next-step development trend of exploration technology is proposed to meet the demand of more technical challenges in the future. 相似文献
100.
Influence of aerosol on regional precipitation in North China 总被引:1,自引:0,他引:1
The possible anthropogenic aerosol effect on regional precipitation is analyzed based on the historical data of precipitation
and visibility of North China. At first, the precipitation amounts from 1960 to 1979 are considered as natural background
values in our study for relatively less intensive industrial activities and light air pollution during that period of time,
then the region is divided into different subregions by applying the clustering method including the significance test of
station rainfall correlations to the time series of 10-day mean rainfall amounts in this period. Based on the rule that the
precipitation characteristics are similar in the same clustering region, the correlation of precipitation amounts among all
stations in each region is thus established. Secondly, for the period from 1990 to 2005, during which, the economy had experienced
a rapid development in this region, the variations of visibility at each station are analyzed. The stations with the absolute
change in visibility less than 0.1 km/a are used as the reference stations, at which it is assumed that precipitation has
not been seriously influenced by anthropogenic aerosols. Then the rainfall amounts of reference stations are used to estimate
the natural precipitation values of the other stations in each clustering region. The difference between estimated precipitation
and measured precipitation amount is thought to result from changes in anthropogenic aerosols. These changes in precipitation
amounts caused by anthropogenic aerosols at each station are calculated using the 10-day mean rainfall values from 1990 to
2005. The analysis results obtained with this method are remarkable if it passes the significance test, and therefore, the
suppression of regional precipitation over the region by anthropogenic aerosol is proved. It is found that this effect is
most remarkable in summer. The influence of anthropogenic aerosols on convective precipitation possibly plays an important
role in this season.
Supported by National Basic Research Program of China (Grant No. 2006CB403706) and National Natural Science Foundation of
China (Grant No. 40475003) 相似文献