聚丙烯纤维复合土抗裂补强特性试验研究

将聚丙烯纤维按不同类型、不同组合、不同含量掺入土中的三轴压缩试验,研究了聚丙烯纤维复合土的应力-应变性状及对复合土强度特性的影响。试验结果表明,加固黏性土要选择分散性好的束状单丝聚丙烯纤维,而不是网状聚丙烯纤维,聚丙烯纤维按占土质量0.2%时为最佳掺入量,束状单丝聚丙烯纤维长度为6 mm+10 mm+15 mm+19 mm的4种组合较为理想,可使聚丙烯纤维复合土微结构联结强度得到明显改善,抗裂补强,黏性土抗剪强度得到极大的提高。     

Climate variability recorded by n-alkanes of paleolake sediment in Qaidam Basin on the northeast Tibetan Plateau in late MIS3

Here we combine n-alkanes preserved in a shell bar section from Qarhan paleolake, Qaidam Basin with the other sedimentary proxies to elucidate the lake evolution process during the period 39.7 to 17.5 14C ka BP (calibrated age ranges from 43.5 to 22.4 cal. ka BP). In different stages, the n-alkane homologues exhibited different distribution modes indicative of variations in the surrounding vegetation and the hydrologic condition of the lake. The n-alkanes proxies (CPIh, ACLh, Paq) have the same trends as th...     

TRMM降水数据在横断山区的精度

利用相关系数法和散点斜率法对横断山区1998~2011年之间月尺度的TRMM 3B43降水数据精度进行了检验。研究表明,TRMM 3B43降水数据与实测数据相关性很强,但是比实测降水量偏大33.9%。在横断山北部大雪山以东地区和南部香格里-贡山-德钦一带三江并流区TRMM 3B43数据误差较大。各个季节TRMM 3B43降水与实测值误差的空间分布有较大区别,但是都表现为北部沿经向分布,南部沿纬向分布的趋势;横断山区高海拔地区气象站点稀少和复杂的下垫面环境是产生观测误差的主要原因。     

安宁河—则木河断裂带1993～2012年重力动态变化

利用安宁河—则木河断裂带区域1993～2012年的流动重力观测数据,作出重力场动态图像和部分重力点值时序变化图,总结在这20年里安宁河—则木河断裂带的活动规律,分析研究安宁河—则木河断裂带区域及其临近区域较大震级的地震孕育过程中区域的重力变化情况,为安宁河—则木河断裂带区域地震预测预报提供经验和参考资料.     

基于GIS的油田站控组态软件研究与实践

针对油田联合站的主要工艺流程、生产要求及自动化仪表的配置情况,在现有力控组态软件的基础上,探讨了一种利用GIS技术特点的组态图应用模式,结合组态软件采集的实时生产数据,结合GIS化的工艺流程,为油田各级领导提供宏观与微观的生产状态展示与分析,辅助生产决策。     

基于AutoCAD二次开发的高斯投影转等积割圆锥投影

目前测制地形图使用的高斯坐标是等角投影,存在面积变形,而在利用地形图进行大面积土地量算时要求应用等积投影地形图。本文针对如何在CASS成图软件中实现高斯投影转换为等积割圆锥投影进行阐述,开发了投影转换功能菜单并进行了转换有效性验证,摈弃了传统的借助其他GIS软件进行投影转换再求积的工作程序。     

Identifying the Sources of Solutes in Karst Groundwater in Chongqing,China: a Combined Sulfate and Strontium Isotope Approach

Groundwater from karst subterranean streams is among the world’s most important sources of drinking water supplies, and the hydrochemical characteristics of karst water are impacted by both natural environment and people. Therefore, the study of hydrochemistry and its solutes’ sources is very important to ensure the normal function of life support systems. In this paper, thirty?five representative karst groundwater samples were collected from different aquifers (limestone and dolomite) and various land use types in Chongqing to trace the sources of solutes and relative hydrochemical processes. Hydrogeochemical types of karst groundwater in Chongqing were mainly of the Ca?HCO3 type or Ca (Mg)?HCO3 type. However, some hydrochemical types of karst groundwater were the K+Na+Ca?SO4 type (G25 site) or Ca?HCO3+SO4 type (G26 and G14 site), indicating that the hydrochemistry of these sites might be strongly influenced by anthropogenic activities or unique geological characteristics. The dissolved Sr concentrations of the studied groundwater ranged from 0.57 to 15.06 μmmol/L, and the 87Sr/86Sr varied from 0.70751 to 0.71627. The δ34S?SO42? fell into a range of ?6.8‰?21.5‰, with a mean value of 5.6‰. The variations of both 87Sr/86Sr and Sr values of the groundwater samples indicated that the Sr element was controlled by the weathering of limestone, dolomite and silicate rock. However, the figure of 87Sr/86Sr vs. Sr2+/[K++Na+] showed that the anthropogenic inputs also obviously contributed to the Sr contents. For tracing the detailed anthropogenic effects, we traced the sources of solutes collected karst groundwater samples in Chongqing according to the δ34S value of potential sulfate sources. The variations of both δ34S and 1/SO42? values of the groundwater samples indicated that the atmospheric acid deposition (AAD), dissolution of gypsum (GD), oxidation of sul?de mineral (OS) or anthropogenic inputs (SF: sewage or fertilizer) have contributed to solutes in karst groundwater. The influence of oxidation of sul?de mineral, atmospheric acid deposit and anthropogenic inputs to groundwater in Chongqing karst areas was much widespread.     

Web2.O环境下基于布鲁克斯方程的地图信息传输模型

各向地图信息传输模型是传统地图信息传输理论在Web2.0时代的延伸与发展,对提升现代地图学的价值具有重要意义.本文通过分析Web2.0地图的特点和相关工作,研究地图制图模式及其相应的地图信息传输模型,引入信息生态学和布鲁克斯方程,重点探索了基于Web2.0地图的各向地图信息传输模型,利用信息学的布鲁克斯方程对Web2....     

梯形面片数据模型及其空间运算应用

提出一种新的基于梯形面片的空间运算方法,该方法将多边形要素预先分解成一系列的梯形面片,后续的空间运算将不再基于原始多边形要素进行操作,而是对分解产生的梯形面片进行更为简便的计算处理。梯形面片模型结合了常见矢量数据模型数据精度高、栅格数据模型运算简单等优点,在执行相关空间运算中与常见矢量和栅格模型相比具有优势。详述了该数据模型,并以点面包含分析和多边形叠置分析等实例探讨了其在空间运算中的应用,测试与分析表明该方法兼具数据精度高、算法实现简单等优点,能较有效地提高空间运算的执行效率。     

GIS技术在地质灾害研究中的应用

GIS是一门介于地球科学、空间科学和信息科学之间的交叉学科,它强大的空间信息处理和分析功能为地质灾害信息的管理提供了有力的工具。在总结GIS技术在地质灾害中应用现状的基础上,分析了基于GIS地质灾害信息系统的优势与不足,结合3S技术和计算机网络的发展趋势,提出了基于网络的多级地质灾害管理信息系统。