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A hierarchical organization approach of multi-dimensional remote sensing data for lightweight Web Map Services 总被引:1,自引:0,他引:1
Yongwang Zhao Chunyang Hu Hualei Shen Dianfu Ma Xuan Li Yonggang Huang 《Earth Science Informatics》2012,5(1):61-75
With the rapid development of the World Wide Web, remote sensing (RS) data have become available to a wider range of public/professional
users than ever before. Web Map Services (WMSs) provide a simple Web interface for requesting RS data from distributed geospatial
databases. RS data providers typically expect to provide lightweight WMSs. They have a low construction cost, and can be easily
managed and deployed on standard hardware/software platforms. However, existing systems for WMSs are often heavyweight and
inherently hard to manage, due to their improper usage of databases or data storage. That is, they are not suitable for public
data services on the Web. In addition, RS data are moving toward the multi-dimensional paradigm, which is characterized by
multi-sensor, multi-spectral, multi-temporal and high resolution. Therefore, an efficient organization and storage approach
of multi-dimensional RS data is needed for lightweight WMSs, and the efficient WMSs must support multi-dimensional Web browsing.
In this paper, we propose a Global Remote Sensing Data Hierarchical Model (GRHM) based on the image pyramid and tiling techniques.
GRHM is a logical model that is independent upon physical storage. To support lightweight WMSs, we propose a physical storage
structure, and deploy multi-dimensional RS data on Web servers. To further improve the performance of WMSs, a data declustering
method based on Hilbert space-filling curve is adopted for the distributed storage. We also provide an Open Geospatial Consortium
(OGC) WMS and a Web map system in Web browsers. Experiments conducted on real RS datasets show promising performance of the
proposed lightweight WMSs. 相似文献
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应用叠前反演弹性参数进行储层预测(英文) 总被引:3,自引:2,他引:1
本文是利用叠前弹性参数反演结果进行致密性含气砂岩储层预测的一个实例研究。随着油气勘探开发的发展,叠前地震数据及其反演结果的应用研究已经广泛用于实际生产中。叠前地震数据的特有属性研究,不仅包括简单的AVO特性,还包括其他的弹性属性的变化特性。本文通过对含气砂岩岩芯弹性属性参数响应特征的分析,发现特定弹性属性参数或其组合可以作为流体检测因子。因此,可以利用叠前地震反演得到不同的弹性属性参数结果,进行储层解释和储层描述。该叠前反演方法是基于Zoeppritz方程的Aki—Richard简化公式建立起来的,根据测井数据和地质解释结果建立初始反演模型,反演的地震数据为叠前时间或深度偏移的共反射点道集数据,反演结果可以是不同的弹性属性参数及其组合。通过对一实际的致密性含气砂岩储层进行叠前弹性属性参数反演,并将反演结果与其它预测结果进行对比分析发现弹性属性参数λ和λρ, λ/μ,以及K/μ能够很好地预测含气储层,而且反演结果很好展现出储层中的含气特性。 相似文献
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本文选择天山开都河流域为研究区,基于巴音布鲁克和大山口2个水文站1957-2011年的日径流量观测资料,采用年最大值法(AM)抽取径流序列样本,用线性趋势法、Mann-Kendall趋势检验和Pettitt检验分析年最大日流量、春季最大日流量和夏季最大日流量序列的变化规律;并运用广义极值分布(GEV)对标准化的最大日流量序列进行拟合,分析洪水频率的变化特征。结果表明:提取的6个最大日流量序列均不存在明显的趋势性,且突变点不显著;其中巴音布鲁克站年最大日流量、春季最大日流量和大山口站年最大日流量序列近似服从Frechet分布,而大山口站春季最大日流量、夏季最大日流量和巴音布鲁克站夏季最大日流量序列则服从Gumbel分布。1980年代以来,开都河流域洪水的发生频次明显增加;巴音布鲁克站夏季洪水次数持续增加,大山口站春季和夏季洪水次数均呈增加趋势,且春季洪水出现时间均有所提前。春季显著升温与冬季降水增加,是春季融雪性洪水出现时间和水量变化的主要原因;而夏季降雨量和降雨频率显著增加,是夏季洪水形成与频率变化的主导因素。 相似文献
139.
Luning Shang Xunhua Zhang Runlin Du Yonggang Jia Zhenxing Tian Bo Han Chuansheng Yang 《Studia Geophysica et Geodaetica》2016,60(4):679-699
In September and October of 2011, a marine magnetic survey was conducted in the southern East China Sea between 120° and 126°E, 26° and 28°N with the research vessel Kexue-3. New magnetic maps with 5 × 5 km grid spacing were generated after meticulous data processing. Based on an analysis of magnetic anomaly features and further calculation results, including the total horizontal derivatives (THD), second order vertical derivatives (SVD) and analytic signal amplitude (ASA), several new tectonic insights on magnetic sources, basement structures and fault properties were obtained. The NE-SW or NNE-SSW oriented magnetic anomaly highs have different sources: (1) The high amplitude, short wavelength magnetic anomalies of the Zhemin Uplift are caused by shallow buried igneous rocks intruded along NE-NEE oriented faults. (2) The high amplitude, moderate wavelength magnetic anomalies of the Diaoyudao Uplift are caused by the metamorphic basement intruded by magmatic rocks. (3) The magnetic sources of the Yandang Uplift and Taibei Uplift in the shelf basin are shallow buried metamorphic basements and deep buried volcanic bodies, respectively. Several NW-SE or NWW-SEE oriented dextral strike-slip fault belts were identified as important tectonic boundaries. Each is composed of several en echelon and partly overlapping secondary faults. Initially formed in the Cretaceous, these fault belts have evolved through multiple periods, propagated seaward with the migration of the basement rifting and accommodated local stress fields in the Cenozoic. 相似文献
140.
气氡观测脱气装置改造的试验研究 总被引:3,自引:1,他引:2
SD-3A自动仪器是“九五”期间中国地震局研制的自动测氡仪器,其脱气装置需要根据观测点的具体情况自行设计、制造。为此,笔者通过对武都殿沟泉脱气装置反复试验、改造,研制完成的脱气装置在武都气氡观测中获得良好效果:整点观测值的离散度明显减小,在6个月中(2002年2月至7月)有101个值超过3倍的均方差,降低到(2003年2月至7月)超过3倍的均方差的数值为零,观测值日变化幅度从几千Bq/L,降低到100Bq/L左右。。 相似文献