Measurements of Equivalent Thicknesses of 3-dimensional PGC-54-like Spiral Galactic Disks     

Gang Li  Zhi-quan Luo  Qiu-he Peng 《Chinese Astronomy and Astrophysics》2010,34(4):11

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非开挖管理软件的设计与开发     

罗艳珍  乌效鸣 《岩土钻凿工程》2010,(1):42-46

利用VisualBasic 6．0语言开发非开挖管理软件,选择Microsoft Office Access 2000作为软件的数据库系统。该软件从公司领导层到公司各部门到作业班组,按照管理需求对非开挖工程数据资料的操作流程进行切合实际的逻辑设计,形成施工主体技术参数、相关辅助信息和人力、物力、财力数据的有机综合管理系统。而且可以直接从窗体输入数据资料,相应的输出Excel、Word形式的数据资料,方便了工程进展情况的查看和资料的整理。软件中根据非开挖工程的要求,相对应的窗体之间创建了关联。软件可以在Windows 9X操作平台下运行,具有窗体友好、操作方便、运行可靠稳定等优点。  相似文献   

Relationships between carbon isotope evolution and variation of microbes during the Permian–Triassic transition at Meishan Section, South China     

Genming Luo  Junhuang Huang  Shucheng Xie  Paul B. Wignall  Xinyan Tang  Xianyu Huang  Hongfu Yin 《International Journal of Earth Sciences》2010,99(4):775-784

This paper investigates kerogen carbon isotopes, the difference between carbonate and kerogen carbon isotopes (Δ¹³C_carb-kero = δ ¹³C_carb − δ ¹³C_kero) and the difference between carbonate and n-C₁₉ alkane compound-specific carbon isotopes (Δ¹³C_carb-n-C19 = δ ¹³C_carb − δ ¹³C _n-C19) during the Permian–Triassic transition at Meishan, South China. The results show that kerogen carbon isotopes underwent both gradual and sharp shifts in beds 23–25 and 26–29, respectively. The differences between carbonate and organic carbon isotopes, both the Δ¹³C_carb-kero and Δ¹³C_carb-n-C19, which are mainly affected by CO₂-fixing enzyme and pCO₂, oscillated frequently during the Permian–Triassic transition. Both the variations of Δ¹³C_carb-n-C19 and Δ¹³C_carb-kero coupled with the alternation between cyanobacteria and green sulfur bacteria indicated by biomarkers. The episodic low values of Δ¹³C_carb-n-C19 corresponded to episodic blooms of green sulfur bacteria, while the episodic high values of Δ¹³C_carb-n-C19 corresponded to episodic blooms of cyanobacteria. The relationships between the variation of carbon isotopes and biota show that the microbes which flourished after the extinction of macroorganism affected the carbon isotope fractionation greatly. Combining the carbon isotope compositions and the pattern of size variation of the conodont Neogondolella, this paper supposes that anoxia of the photic zone at bed 24 was episodic and it would be caused by the degradation of terrigenous organic matters by sulfate reducing bacteria in the upper water column. Considered together with results from previous research, the high resolution variation of the biogeochemistry presents the sequence of the important geo-events during the Permian–Triassic crisis.  相似文献   

基于Flex的气象信息网络发布平台设计与实现   总被引：2，自引：2，他引：0       下载免费PDF全文

孙利华  吴焕萍  郑金伟  罗兵  王琪  胡利霞  郑卫江  吕终亮 《应用气象学报》2010,21(6):754-761

通过分析气象数据的特点和RIA (Rich Internet Applications) 技术的优势,结合系统建设目标提出了基于Flex的网络GIS气象信息发布平台的总体框架, 并详细介绍了该平台的主要功能。对系统建设的关键技术问题进行详细分析,主要包括数据组织与管理、气象数据转换、地图服务缓存以及基于Flex的地图展现技术等。系统运行结果表明:与传统气象网络GIS相比该系统具有界面元素丰富、交互响应快、大数据量的显示效率大大提高等方面的优势。该系统为气象工作人员、应急气象服务及公众提供了一个实时、快速、基于网络的气象信息共享平台。  相似文献   

基于GIS的雷电灾害监测预警与数据处理系统   总被引：1，自引：0，他引：1  

路明月  张其林  骆兴江  耿敏  杨凡  黄容 《气象科技》2010,38(6):832-837

针对雷电灾害涉及的关键问题,基于ArcEngine开发平台,结合大型网络数据库sqlServer2005与空间数据库模型GeoIataBase,设计了具有3层逻辑结构的系统构架方案,构建了基于GIS的雷电监测预警与数据处理系统。该系统有效地将各种雷电数据与GIS平台进行无缝对接,并整合雷电预测模式,实现各种雷电数据基于GIS的实时监测处理与预测预警以及高效组织、存储与管理,满足各种雷电信息查询处理分析的需求;为气象部门对雷电灾害天气的监测、预报预警以及各种数据基于地理信息的处理分析等提供了有效的可视化平台,同时也为GIS与气象专业领域的结合进行了有益的探索。  相似文献   

从2009年度Nature杂志看气候变化研究进展   总被引：4，自引：1，他引：3       下载免费PDF全文

戴洋  罗勇  李秀萍 《气候变化研究进展》2010,6(2):154-156

<正>英国Nature杂志是世界著名的自然科学类综合学术期刊,代表着自然科学各门学科的最前沿研究动态。在大气科学及相关领域研究中,气候变化一直是Nature杂志最关心的内容。随着气候变化加剧、社会瞩目度的不断上  相似文献   

Changes in wind speed over China during 1956–2004     

Ying Jiang  Yong Luo  Zongci Zhao  Shuwang Tao 《Theoretical and Applied Climatology》2010,99(3-4):421-430

Based on two observational data sets in China from 1956 to 2004, wind speed changes are analyzed. The annual mean wind speed (MWS), days of strong wind (SWDs), and maximum wind (MW) all show declining trends over broad areas of China. Only in the southeastern Tibetan Plateau and the regions from the Great Bend of the Yellow River southward to Yunnan and Guangxi Provinces wind speeds are not significantly reduced, but rather, in partial, these regions’ winds speeds are slightly increased. The regions with declining trends match the areas with relatively strong observed winds and the regions without significant declining trends match the areas with light observed winds. In the meantime, the regions with relatively strong winds correspond to areas of reduced days of SWDs. Trends for both increasing intensities and for the number of days of light winds both impact the installation of wind energy facilities. These may be advantageous to the development of wind energy in different regions. Urbanization, the change of anemometers, or relocation of stations are factors that are mildly responsible for the decreasing trend of MWS. The main reason for the decreasing trend is that under the background of global warming, the contrasts of the sea level pressure, and near-surface temperature between the Asian continent and the Pacific Ocean have become significantly smaller, and the east Asian trough has shifted eastward and northward, and has weakened as well. Both East Asian winter and summer monsoons are decreasing, and all of these impacts have resulted in declines of MWS in China.  相似文献   

广西龙州地区双层含铝岩系地质特征与找矿意义     

韦访  黄文芳  罗家元 《江苏地质》2023,47(4):358-368

对龙州地区合山组和都安组铝土岩（矿）层进行系统采样分析，并与堆积铝土矿进行对比研究，结合含铝岩系岩性与矿物特征发现，合山组、都安组铝土岩（矿）矿石矿物无显著差异，主要为一水硬铝石、高岭石、（鲕）绿泥石，其次为赤铁矿（针铁矿）集合体和碎屑物（岩屑、玻屑、砾屑），普遍存在大量（铁）凝胶。常量、微量、稀土元素特征及相关图解显示，合山组、都安组铝土岩（矿）均可能为该区堆积铝土矿的矿源层。Ni-Cr图解显示合山组铝土岩（矿）可能来自与火山物质有关的玄武岩，都安组铝土岩（矿）来源于卡斯特岩溶，堆积铝土矿除部分落入玄武岩、碳酸盐岩区以外，大多位于页岩、板岩内，表明该区堆积铝土矿存在多源性。微量元素Be、Ga、Sr、Ba含量与Sr/Ba、V/Zr、Zr/Cu含量比值等沉积环境元素特征表明该区原生铝土岩（矿）沉积环境为陆相；δCe分析显示铝土岩（矿）沉积环境有所差异，合山组表现为氧化环境，都安组则表现为还原环境。Th、U含量及Th/U含量比值显示该区铝土岩（矿）成矿以混合作用为主，并经历了较强的风化作用；δEu分析表明合山组、都安组铝土岩（矿）分别形成于被动大陆边缘与活动大陆边缘。合山组、都安组含铝岩系均发育不同程度的铝土岩（矿）层，都安组铝土岩（矿）部分样品已达工业边界指标，可作为沉积铝土矿勘查的主要目的层。  相似文献   

THE PROGRESS IN URBAN SOCIAL SPACTIAL DIFFERENTIATION STUDY OF CHINA     

吴启焰  罗俊彦 《中国地理科学(英文版)》1999,9(3):206-212

Ｕｒｂａｎｓｏｃｉａｌｇｅｏｇｒａｐｈｙａｎｄｉｔｓｓｕｂｆｉｅｌｄ—ｕｒｂａｎｓｏｃｉａｌｓｐａｔｉａｌｄｉｆｆｅｒｅｎｔｉａｔｉｏｎｈａｖｅｂｅｅｎｄｅｖｅｌｏｐｅｄｓｉｎｃｅｔｈｅ１９６０ｓ．Ｔｉｌｌｎｏｗ，ｂｙｉｔｓｂａｓｅｍｅｎｔａｎｄｔｈｅｏｒｙ，ｉｔｃａｎｂｅｄｉｖｉｄｅｄｉｎｔｏｔｈｒｅｅｓｔａｇｅｓａｎｄｆｏｕｒｒｅｓｅａｒｃｈｓｃｈｏｏｌｓ：１）ｍｅｔｈｏｄｏｌｏｇｉｃａｌｄｅｓｃｒｉｐｔｉｏｎｓｔａｇｅ；２）ｂｅｈａｖｉｏｒｓｔｕｄｙｓｔａｇｅ；３）ｒａｄｉｃａｌＭａｒ…  相似文献   

基于光纤自相位调制多波长全光再生的色散管理优化     

张婧  潘炜  闫连山  罗斌 《海洋学报》2010,32(10):7002-7007

针对基于光纤自相位调制效应的多波长全光再生系统,分析了光纤平均色散对再生器品质因子改进量的影响,提出一种色散管理优化方法.由于波长间色散差异会导致再生系统性能的稳定性下降,通过选择色散补偿光纤和单模光纤的长度,使其合成的色散曲线与各波长分别达到最优再生性能时对应的色散曲线近似拟合,同时保证该色散曲线落在性能满意度高的色散区域,然后调整信号输入功率和滤波器的偏移量,可有效改善多波长再生性能的稳定性,实现再生器的色散管理优化.  相似文献