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81.
通过分析地震数据EDAS Event格式与SEED格式在文件头与数据部分存储的特点与规律,利用Visual Basic语言研发地震波形数据处理软件.利用此软件,可以完成地震记录数据的格式转换,以及数据的抽取与合并,保证数据记录的连续与衔接,提高数据的连续性和利用价值.  相似文献   
82.
Xuanwei and Fuyuan, located in southwest China, are two counties with extremely high lung cancer incidence. Pollution, relative to coal combustion, especially serious air pollution generated by burning smoky coals in unvented households was the most predominant cause. Quartz as a possible inorganic carcinogen in all typical coals (18 sites in Xuanwei and 14 sites in Fuyuan) were sampled and examined to determine the relationships between quartz content and lung cancer incidence. Scanning electron microscope-energy dispersive X-ray apparatus and X-ray diffractometer were employed for quartz analysis. It showed that it coincided with studies reported before in Xuanwei. Coal samples from high cancer incidence areas were all examined with high content of quartz, while coal samples from low cancer incidence areas with no content of quartz. However, data in Fuyuan received reverse results; many samples from low lung cancer incidence areas were found with quartz, but some samples from high lung cancer incidence areas were not found at the same detection limits. It indicated that quartz content in local coals has no significant relationship to lung cancer. This study added basic data and should be helpful to the future study on the etiology of lung cancer.  相似文献   
83.
The effects of cloud structures on microwave radiances at frequencies from 89-190 GHz are investigated by simulations using the Goddard cumulus ensemble model data as input for a radiative transfer model. It was found that the brightness temperatures at these frequencies have different sensitivities to clouds with a tilted structure. The different sensitivities to altitude and amount of hydrometeors allow the estimation of the canting angle and tilt direction of tilted clouds using brightness temperatures at the water vapor channels at 183.3 /spl plusmn/ 1 and 183.3 /spl plusmn/ 7 GHz. The estimated canting angle and tilt direction are in agreement with the model situation. This method provides a potential to estimate tilted convective structures from microwave radiometric observations at 183.3 /spl plusmn/ 1 and 183.3 /spl plusmn/ 7 GHz. It is applied to a tilted storm observed from the National Aeronautics and Space Administration's ER-2 aircraft flying at about 20 km on August 26, 1998 during the third Convection and Moisture Experiment using the observed downlooking brightness temperatures at the water vapor channels of a Millimeter-wave Imaging Radiometer. The estimated results are in good agreement with the realistic storm situation obtained from the simultaneous observations of the ER-2 Doppler radar. This method also provides information about the vertical displacement of cloud structure and thereby to estimate the accurate location of surface rainfall. This is important when validating precipitation retrieval based on observations of the ice scattering above surface rainfall against surface rain observations using the microwave frequencies sensitive to high altitudes.  相似文献   
84.
首先简要介绍了我国工程建设监理制的建立、运行及发展概况;然后就工程建设监理及监理单位性质、监理模式以及我国实施工程建设监理的有关法律、法规、具体内容等进行了详细阐述;最后指出了工程建设监理与政府工程质量监督的区别。  相似文献   
85.
联合多代卫星测高资料反演中国南海重力异常   总被引:1,自引:0,他引:1       下载免费PDF全文
联合HY-2A、Geosat、ERS1/2、Envisat、T/P、Jason1/2等多颗测高卫星,通过共线处理和交叉点平差削弱海面时变效应和径向轨道误差等影响,以Jason-1测高卫星作为参考,对多代测高卫星进行基准统一,消除测高数据的不一致性,基于全球EGM2008重力场模型,采用移去恢复技术和逆Vening-Meinesz公式反演中国南海(0°~23°N,103°~120°E)2'×2'重力异常,与船测重力数据比较,均方根误差为4.9m Gal。  相似文献   
86.
根据大量岩石薄片观察、扫描电镜和X?衍射分析,研究陇东地区典型区块三叠系延长组长6—长8段特低渗透—致密砂岩的岩石学特征、孔隙成因等,探讨成岩作用类型及主要控制因素,剖析延长组长6与长8成岩作用的差异性。研究表明:该区砂岩经历的成岩作用主要有压实作用、胶结作用、溶解作用等,建立了三角洲和重力流成岩演化模式序列,研究区目前处于中成岩A?B期;并从储层形成的物源、沉积环境、古气候等方面的差异性,探讨了华庆区块长63和马岭区块长81成岩作用差异性的成因。由于长6较长8粒度细、杂基含量较高,其压实作用强,原生粒间孔保存较少,早期绿泥石膜胶结不发育,含铁碳酸盐胶结物及自生伊利石含量高,砂岩储层物性较差。  相似文献   
87.
基于WAVEWATCH III,在输入相同的风场条件下,评估了三个输入耗散项WAM3,WAM4以及TC96在是否考虑大气稳定性时的模拟能力。通过5组实验,用南海的测波雷达数据以及研究区域内HY-2高度计的有效波高数据对不同源项的模拟结果进行了比较分析,研究区域为100-135°E,0-35°N。对TC96中的风速校正参数进行了敏感性分析。结果表明,这几种源项在涌浪占主导时的模拟效果都不太理想;考虑大气不稳定性的TC96源项模拟的效果最好;大气不稳定性的影响是以一种所谓的“高效风速”的策略来反映的,其中最重要的一个参数为风速转换参数,这个参数非常敏感,在对特定区域进行模拟之前,应先分析出这个参数的最优值。  相似文献   
88.
Climate warming and economic developments have created pressures on the ecological systems that human populations rely on, and this process has contributed to the degradation of ecosystems and the loss of ecosystem services. In this study, Landsat satellite data were chosen as the data source and the Koshi River Basin (KB) in the central high Himalayas as the study area. Changes in land cover and changes in the value of ecosystem services between 1990 and 2010 were analyzed and the land cover pattern of the KB in 2030 and 2050 was modeled using the CA-Markov model. Changes in land cover and in the value of ecosystem services in the KB for the period 2010-2050 were then analyzed. The value of ecosystem services in the KB was found to decrease by 2.05×108 USD y-1 between 1990 and 2010. Among these results, the services value of forest, snow/glacier and barren area decreased, while that of cropland increased. From 1990 to 2050, forest showed the largest reduction in ecosystem services value, as much as 11.87×108 USD y-1, while cropland showed the greatest increase, by 3.05×108 USD y-1. Deforestation and reclamation in Nepal contributed to a reduction in the value of ecosystem services in the KB. Barren areas that were transformed into water bodies brought about an increase in ecosystem services value in the lower reaches of the Koshi River. In general, this process is likely to be related to increasing human activity in the KB.  相似文献   
89.
河北南部及邻近地区中小地震震源机制特征分析   总被引:1,自引:0,他引:1  
利用P波初动和振幅相结合的广义极性振幅技术法(GPAT),反演2007-2016年河北南部及邻近地区发生的368个ML≥2.0中小地震震源机制解,利用统计方法和系统聚类方法,分析震源机制解参数特征。结果表明,河北南部及邻区中小地震以走滑地震为主;正断层和逆断层相对较少,断层面以倾斜或直立为主,断层运动表现为左旋走滑和右旋走滑,应力作用以水平和近水平推扭方式为主。  相似文献   
90.
大气和地下水中SF6测试技术   总被引:3,自引:0,他引:3  
SF6是一种无色、无嗅、无毒、不易燃的惰性气体,具有良好的绝缘性、灭弧性和散热性。由于SF6具有化学惰性、大气圈和水圈中本底浓度低、检测灵敏度高等优点,它成为一种较为理想的大气、水文示踪剂。另外,在年轻地下水测年领域,SF6法已经逐渐有取代其他测年工具(3H法、CFCs法、3H/3He法)的趋势,特别适合研究1970年以后补给水的年龄。本文基于气相色谱仪和电子捕获检测器,设计了一套SF6提取制样分析系统,发展了SF6测试技术。  相似文献   
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