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61.
FY2海面温度产品质量检验方法与误差分析   总被引:2,自引:0,他引:2  
王素娟  陆风  张鹏  张晓虎  崔鹏  王维和 《气象》2013,39(10):1331-1336
主要介绍了风云二号静止气象卫星海面温度产品的质量检验方法及检验流程,给出了FY2E业务海面温度产品和FY2F海面温度算法的质量检验结果,并从误差统计、反演算法、系统设计等方面分析了目前FY2海面温度产品与国外卫星海面温度产品差异大的原因。现场海面温度质量检验和分析场海面温度交叉检验各有优缺点。现场海面温度质量检验能够对FY2 SST产品给于客观的评价。国外分析场海面温度具有时效性好、全球覆盖且质量均一的优点,分析场海面温度交叉检验能满足FY2 SST质量检验的时效性,是对FY2 SST的相对检验。通过静止卫星海面温度产品质量检验信息可以为产品研发人员和相关用户提供参考。  相似文献   
62.
嫩江断裂构造及其与地震活动的关系   总被引:4,自引:0,他引:4  
本文从卫片解译、钻孔资料、地球物理场特征等方面阐述了嫩江断裂的存在标志,同时对该断裂的性质、活动时代及其与地震的关系进行了讨论。认为沿该带分布的北西向及东西向断裂活动与地震关系密切,尤其是存在的地震围空区值得密切关注。  相似文献   
63.
本文简要介绍了用中国研制的人造卫星激光测距仪(SLR),安装在阿根廷与San Juan大学天文台开展SLR合作观测与研究的意义,以及这个SLR系统的指标和性能.该仪器系统于2006年初在阿根廷国立San Juan大学天文台工作以来,进展良好,取得了观测数量丰富、精度高的优良结果.该合作的进展状况和未来的发展设想也在文中做了介绍.  相似文献   
64.
Fault has an important influence on the storage and movement of geothermal water. The Zhangzhou Basin is wholly located in a granodiorite rock mass. Due to the low permeability of granodiorite, faulted structure has an evident control action on the hydrothermal activity of geothermal fields. Hot springs in Zhangzhou Basin crack along Pingtan-Dongshan Fault to the northeastern direction and emerge along Fu’an-Nanjing Fault. Through measurement of the temperature of several hot springs in the Basin, we found the temperature along the northwestern direction of Zhangzhou-Tianbao Fault is high and the temperature gap between the two sides of Yangxi-Yuanshan Fault is huge; the estimation of geothermal reservoir temperature of geothermal water through quartz geothermometer indicates that the geothermal reservoir temperature of the northern area of Nanjing-Xiamen Fault is obviously higher than that of southern area. Such result indicates that Fault obviously obstructs underground heat source. Under the condition that the average geothermal gradient of the Zhangzhou Basin is set, the circulation depth of the geothermal water of the Zhangzhou Basin measured by geothermal reservoir temperature is 3 550-5 200 m and the circulation depth of the geothermal water of the north of Nanjing-Xiamen Fault is deeper than that of the South.  相似文献   
65.
在城市化进程不断加快的今天,城市地下空间开发利用已经成为提高城市容量、缓解交通、改善环境的重要手段。为全面深化对泰安城市地下空间的认识,有效挖掘城市后备空间资源的巨大潜力,通过综合集成钻孔编录、地质图件和数字地形图等多源地学数据,借助MapGIS三维地质建模软件,初步建立起泰安城市三维地质模型,以直观的方式表达工程岩土体空间分布等地质信息,为更好地保护利用泰安市地下空间提供地质依据。  相似文献   
66.
The geological structure exposed by paleoearthquake trenches is the key material to the right cognition of fault activity and paleoearthquake. However, paleoearthquake trenching inevitably destroys active tectonic geomorphic evidence and trench exposures are usually difficult to reserve. The conventional process of recording the delicate geological information, manually constructing photomosaics by image-editing software, is time-consuming and produces undesirable artificial distortions. Herein, we explored the process of constructing trench orthophotomosaics and the 3D image model using the Image-based Modeling technology and applied it to the Liutiaohe trench across the Tianqiaogou-Huangyangchuan Fault, Gansu Province. Based on the 3D image modeling and orthophotomosaic, we firstly constructed the control points and scale bars on cleaned trench walls and collected photos of all sections of the trench with a digital camera in the field, and then reconstructed the 3D model of the trench through the Agisoft PhotoScan, an efficient image-based modeling software, and finally yielded the 3D image model of the trench and othophotomasaics of the trench exposures. The results show that the automated workflow can produce seamless, sub-millimeter-level high-resolution photomosaics more quickly, with precision in the centimeter range, and the 3D image model is of great help to identify strata and geological structures in trenches with much lower capital and labor costs and low expertise levels compared with LiDAR, meanwhile, the 3D archive benefits the share and communication and even allows future reinterpreting the site using new insights.  相似文献   
67.
Although Lanzhou is one of the most heavily polluted cities in China, the composition of its air pollutants have not yet been studied in detail. The data of four months on the concentrations and compositions of ions from daily air-filter samples in the winter and spring during 2007–2008 were analyzed to investigate temporal trends and their possible causes. The results indicate that mean concentrations of almost all the aerosol components are greater in winter than in spring due to stronger emissions in winter and weaker localized dispersion. Spring dust storms are the major cause of the highest peak PM10 concentrations recorded during the study period; however, these elevated levels were transient. Ion concentrations related to coal combustion show the greatest reduction from winter to spring, while the concentrations of strong crustal components show a less-pronounced reduction. Strong cycles in the levels of particulate matter (PM) and all ions are also observed during the winter months due to meteorological conditions. Depending on the season, nine different ions accounted for 20%–50% of the PM concentration. The particle size of polluting ions was constant at times of increasing PM concentrations (particularly during winter), whereas the particle size of crustal ions increased dramatically during spring dust storms. Local meteorological conditions (especially wind speed) have a strong influence on the levels of pollutants. Four dust storms were noted, including one during winter. In summary, the regional transport of desert dust from the Gobi can significantly affect air quality and the chemical composition of aerosols in Lanzhou. The dust storms can strongly increase concentration of crustal ions, which are characteristics of deserts in northwestern China. This observation is in agreement with back-trajectories, which show reduced levels of pollutant ions during dust storms. Data on nitrate:sulfate ratios indicate that stationary point sources are the main source of ions rather than mobile sources.  相似文献   
68.
南海北部外陆架和上陆坡海底滑坡稳定性研究   总被引:9,自引:0,他引:9  
海洋工程地质调查发现,在南海北部外陆架和上陆坡海底,有大片滑坡,其水深范围约在180-650m之间,它们沿着陆架外缘坡折处呈北东-南西方向分布,其具体位置往往与古三角洲前缘的海底陡坎及古海岸线位置密切相关,大量浅层地震,旁侧声纳,底质取样分析和土体力学理论计算表明,本区滑坡主要是由于地形坡度,沉积物特性,土体自身重力,它们是区内海底很不稳定的地带,是一种重要的地灾害因素,在海洋工程地质设计和实施时  相似文献   
69.
70.
江苏省国内旅游线路节点配置研究   总被引:1,自引:0,他引:1  
基于旅行社旅游线路网络调查资料,本研究运用频数分析、聚类分析、比较分析等研究方法,深入分析了江苏省国内旅游线路中的城市节点、景区节点、临时节点等三大类旅游线路节点配置特征。结果表明:(1)可以将进入江苏国内旅游205条线路中的26个城市节点分为3个全国旅游热点城市节点、6个全国旅游城市节点、6个长三角区域旅游热点城市节点、11个省内短途旅游城市节点,南京和苏州是最主要的门户型和离境型城市节点;(2)随着客源地距离的增大,进入江苏国内旅游线路中的城市节点和景区节点数量都相应减少,旅游线路景区节点分布的地域集中性增强,相应城市节点内部的景区节点选择差异性也增大;(3)对游客具有较大吸引力的临时节点主要包括地方知名产品的生产和购物场所,以及富有当地文化特征的历史街区、现代CBD等。  相似文献   
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