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61.
针对大比例尺地形图质量检验工作中外业工作占比大、检验效率低的状况,提出了利用车载移动测量系统进行大比例尺地形图质量检验,设计了一套新的检验工作流程,并通过与常规检验方式的比较,验证了新技术应用于质检工作中的可行性和有效性,为建立高效率的质检模式提供了全新思路。  相似文献   
62.
Large-scale Cenozoic magmatic rocks from the interplay between the Indian and Eurasian plate are exposed in the Yulong porphyry copper belt in the northern Jinshajiang–Ailaoshan domain. Alkali-rich magmas along the Yulong porphyry copper belt can reveal the tectono-magmatic processes in the Sanjiang region. In this study, we present new zircon U–Pb–Hf isotopes and whole rock geochemistry of Cenozoic granitoids from the Zhalaga area in the northern Yulong porphyry copper belt. The Zircon U–Pb dat...  相似文献   
63.
引用满意度指数的概念,根据实际满意度调查的数据,利用多元统计分析的方法,对2010届毕业生选择的第一份工作的满意度进行了实证分析,得出影响毕业生就业满意度的主要因子分别为"单位内部因子"、"个体发展因子"、"外显所得因子",其中起主要影响的因素是"单位因子",三者的影响程度依次递减,同时对2010届大学毕业生对工作的满意程度进行了预测.  相似文献   
64.
The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian-Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the World Climate Research Programme’s Coupled Model Intercomparison Project Phase 5 (CMIP5) were evaluated. Based on climatology of the twentieth-century simulations, most of models have a reasonably realistic representation of summer monsoon WVT characterized by southeast water vapor conveyor belt over the South Indian Ocean and southwest belt from the Arabian Sea to the East Asian. The correlation coefficients between NCEP reanalysis and simulations of BCC-CSM1-1, BNU-ESM, CanESM2, FGOALS-s2, MIROC4h and MPI-ESM-LR are up to 0.8. The simulated CEF depicted by the meridional wind along the equator includes the Somali jet and eastern CEF in low atmosphere and the reverse circulation in upper atmosphere, which were generally consistent with NCEP reanalysis. Multi-model ensemble means (MME) can reproduce more reasonable climatological features in spatial distribution both of WVT and CEF. Ten models with more reasonable WVT simulations were selected for future projection studies, including BCC-CSM1-1, BNU-ESM, CanESM2, CCSM4, FGOALS-s2, FIO-ESM, GFDL-ESM2G, MRIOC5, MPI-ESM-LR and NorESM-1M. Analysis based on the future projection experiments in RCP (Representative Concentration Pathway) 2.6, RCP4.5, RCP6 and RCP8.5 show that the global warming forced by different RCP scenarios will results in enhanced WVT over the Indian area and the west Pacific and weaken WVT in the low latitudes of tropical Indian Ocean.  相似文献   
65.
赤峰市巴林左旗山杏气候资源分析与区划   总被引:1,自引:0,他引:1  
通过对巴林左旗山杏资源和生产现状的调查与分析,利用相关分析方法确定出对山杏生产有重要影响的区划指标,采用回归分析方法建立了产量与主要气象要素及地理因子关系模型,借助于1:25万地理信息数据和气候因子空间分布模型,应用GIS分析技术实现了该地区山杏气候资源区划,并进行了分区描述,提出了生产建议和减灾对策。为有效开发利用巴林左旗农业气候资源,合理开发利用山杏林,提供科学依据。  相似文献   
66.
Tropical cyclone(TC) genesis over the western North Pacific(WNP) is analyzed using 23 CMIP5(Coupled Model Intercomparison Project Phase 5) models and reanalysis datasets. The models are evaluated according to TC genesis potential index(GPI). The spatial and temporal variations of the GPI are first calculated using three atmospheric reanalysis datasets(ERA-Interim, NCEP/NCAR Reanalysis-1, and NCEP/DOE Reanalysis-2). Spatial distributions of July–October-mean TC frequency based on the GPI from ERA-interim are more consistent with observed ones derived from IBTr ACS global TC data. So, the ERA-interim reanalysis dataset is used to examine the CMIP5 models in terms of reproducing GPI during the period 1982–2005. Although most models possess deficiencies in reproducing the spatial distribution of the GPI, their multimodel ensemble(MME) mean shows a reasonable climatological GPI pattern characterized by a high GPI zone along 20?N in the WNP. There was an upward trend of TC genesis frequency during 1982 to 1998, followed by a downward trend. Both MME results and reanalysis data can represent a robust increasing trend during 1982–1998, but the models cannot simulate the downward trend after 2000. Analysis based on future projection experiments shows that the GPI exhibits no significant change in the first half of the 21 st century, and then starts to decrease at the end of the 21 st century under the representative concentration pathway(RCP) 2.6 scenario. Under the RCP8.5 scenario, the GPI shows an increasing trend in the vicinity of20?N, indicating more TCs could possibly be expected over the WNP under future global warming.  相似文献   
67.
本文分析了安徽潜山双河大理岩的岩石化学成分、微量元素和稀土元素,并通过锆石“CL”图像,确定变质锆石和变质复合锆石测点位置.定年结果:①变质复合锆石中老核“继承锆石”,共测定32个点,年龄范围在2357~342 Ma:属于元古宙的15个,年龄范围在2357~572 Ma,古生代17个,年龄范围在524~342 Ma;②变质锆石共测定8个点,其中5个点年龄范围在249~234 Ma,相当超高压变质时间,年龄范围在228~221Ma,即退变质时间.前述大量古生代的岩浆碎屑锆石(继承锆石)的存在,表明双河大理岩的原岩泥灰岩,时代不会早于古生代.  相似文献   
68.
Recent studies, focused on dihedral angles and intersection processes, have increased understandings of conjugate fault mechanisms. We present new 3-D seismic data and microstructural core analysis in a case study of a large conjugate strike-slip fault system from the intracratonic Tarim Basin, NW China. Within our study area, "X" type NE and NW trending faults occur within CambrianOrdovician carbonates. The dihedral angles of these conjugate faults have narrow ranges, 19° to 62° in the Cambrian and 26° to 51° in the Ordovician, and their modes are 42° and 44° respectively. These data are significantly different from the ~60° predicted by the Coulomb fracture criterion. It is concluded that:(1) The dihedral angles of the conjugate faults were not controlled by confining pressure, which was low and associated with shallow burial;(2) As dihedral angles were not controlled by pressure they can be used to determine the shortening direction during faulting;(3) Sequential slip may have played an important role in forming conjugate fault intersections;(4) The conjugate fault system of the Tarim basin initiated as rhombic joints; these subsequently developed into sequentially active "X" type conjugate faults; followed by preferential development of the NW-trending faults; then reactivation of the NE trending faults. This intact rhombic conjugate fault system presents new insights into mechanisms of dihedral angle development, with particular relevance to intracratonic basins.  相似文献   
69.
?????4??????????????Ni002A??????????????????1)???????????Ni002A????????????????????????2)???????????????????f????????????????б????????????3)SDL1X??DiNi03??DNA03???????????????????????????DL101C??????????????????????????  相似文献   
70.
对青海共和高寒沙地植被恢复区不同林龄(6年、11年、16年和21年)乌柳(Salix cheilophila)人工防护林根系分布及根量进行了调查、测定,同时测定了土壤有机质含量的垂向变化。结果表明:①不同林龄乌柳林根系主要由中根和细根构成,其数目占土壤剖面根系总数的90%以上,其中又以直径小于2.0mm细根所占比例最高,细根占剖面根系总数的50%以上;②各林龄乌柳根系在0~50cm土层分布较为集中,在30cm以下土层,根量随深度的增加逐渐减少,6年生乌柳林根系垂直分布在0~130cm,20年生乌柳可达200cm,随植被恢复时间的增长,各林龄根量显著增加(p0.05);③各林龄乌柳林有明显发达的垂直主根,属典型的垂直状根系,随植株不断生长,根系表现出深根性;④以不同深度根系重量作为解释变量,以土壤有机质含量作为响应变量,回归结果显示不同林龄乌柳林根系重量显著影响土壤有机质含量(p0.001),这也为评价沙地植被改良土壤功能提供了依据。  相似文献   
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