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151.
The major contribution of this paper relates to the practical advantages of combining Ground Control Points (GCPs), Ground Control Lines (GCLs) and orbital data to estimate the exterior orientation parameters of images collected by CBERS-2B (China–Brazil Earth Resources Satellite) HRC (High-resolution Camera) and CCD (High-resolution CCD Camera) sensors. Although the CBERS-2B is no longer operational, its images are still being used in Brazil, and the next generations of the CBERS satellite will have sensors with similar technical features, which motivates the study presented in this paper. The mathematical models that relate the object and image spaces are based on collinearity (for points) and coplanarity (for lines) conditions. These models were created in an in-house developed software package called TMS (Triangulation with Multiple Sensors) with multi-feature control (GCPs and GCLs). Experiments on a block of four CBERS-2B HRC images and on one CBERS-2B CCD image were performed using both models. It was observed that the combination of GCPs and GCLs provided better bundle block adjustment results than conventional bundle adjustment using only GCPs. The results also demonstrate the advantages of using primarily orbital data when the number of control entities is reduced. 相似文献
152.
讨论了灰色物元法在含水层储气库参数优化问题中的应用。天然气地下储气库的建造是一项大型、复杂、具有多目标性的工程项目,包括固定资产投资、钻井、修井、注采气工艺完善、地面建设等,需要上亿元的投资,因此其方案的确定,事关重大,必须在建设前期进行充分的技术和工程论证。地下储气库设计方案的优选需要考虑使用功能、技术性、经济性、安全性、环境影响等诸方面的效果进行综合论证,来确定最优方案。由于确定地下储气库优化设计指标类型的多样性,不相容性,且其量纲也不尽相同,甚至有些指标只能是定性描述的非量化灰数,这就导致地下储气库建造设计方案的优选是属灰色系统问题。利用灰色物元分析法优选储气库参数,可以使储气库的参数设计达到最佳。 相似文献
153.
地图扫描数字化的点位精度分析 总被引:21,自引:0,他引:21
地图扫描数字化为建立GIS提供了一种较好的原始地图数据获取方法,本文讨论了影响地图扫描数字化精度的诸种因素,分析了定向点和采样点误差对地图数字化结果的影响,发展了定向点和采样点的自动对中算法,从而保证地图扫描数字化的精度能满足建立GIS的要求。 相似文献
154.
Piotr W. Mirowski Daniel M. Tetzlaff Roy C. Davies David S. McCormick Nneka Williams Claude Signer 《Mathematical Geosciences》2009,41(4):447-474
This research introduces a novel method to assess the validity of training images used as an input for Multipoint Geostatistics,
alternatively called Multiple Point Simulation (MPS). MPS are a family of spatial statistical interpolation algorithms that
are used to generate conditional simulations of property fields such as geological facies. They are able to honor absolute
“hard” constraints (e.g., borehole data) as well as “soft” constraints (e.g., probability fields derived from seismic data,
and rotation and scale). These algorithms require 2D or 3D training images or analogs whose textures represent a spatial arrangement
of geological properties that is presumed to be similar to that of a target volume to be modeled. To use the current generation
of MPS algorithms, statistically valid training image are required as input. In this context, “statistical validity” includes
a requirement of stationarity, so that one can derive from the training image an average template pattern. This research focuses
on a practical method to assess stationarity requirements for MPS algorithms, i.e., that statistical density or probability
distribution of the quantity shown on the image does not change spatially, and that the image shows repetitive shapes whose
orientation and scale are spatially constant. This method employs image-processing techniques based on measures of stationarity
of the category distribution, the directional (or orientation) property field and the scale property field of those images.
It was successfully tested on a set of two-dimensional images representing geological features and its predictions were compared
to actual realizations of MPS algorithms. An extension of the algorithms to 3D images is also proposed. As MPS algorithms
are being used increasingly in hydrocarbon reservoir modeling, the methods described should facilitate screening and selection
of the input training images. 相似文献
155.
车载γ能谱方法找金是寻找隐伏金矿床的物化探新技术。用它可有效地预测区域金成矿远景区。在冀北等地区(4.91万km ̄2)采用车载γ能谱测量方法,取得地质体内63416个γ能谱测点数据,按地质体大小使用滑动滤波技术,处理区域地质体中的γ能谱数据并绘制了参数分布特征图件。在深入研究γ能谱参数分布特征所反映的区域金成矿地质环境的基础上,建立了一套与区域金成矿相关的γ能谱组合参数,提取了γ能谱参数特征信息。结合地质资料,研究工作地区的金成矿地质环境,预测了两片远景区,部分地区经验证,见有金矿化。研究结果表明,车载γ能谱方法用于区域找金是一种快速、节资、有效的方法。 相似文献
156.
传统考虑后期使用年限的地震动参数研究,在建筑物抗震设计中的应用,缺乏地震危险性分析和建筑物损伤指数分析,应用性差。提出新的地震动参数在建筑物抗震设计中的应用方法,以地震危险性分析为基础,通过水平地震动加速度衰减关系方程,求得建筑场地水平向基岩峰值加速度和反应谱,以此得到地震动加速度反应谱方程,利用该方程获得地震动反应谱参数,采用变形和线性组合构建损伤指数模型,获取地震波作用下地震动参数对建筑物损伤程度。实验结果表明,利用所提方法得到的地震动反应谱最小误差为0.563,小于允许误差4.0;在50年超越概率63%的条件下地震动参数值分别为0.26、0.095,所提方法可在规定误差范围内得到地震动反应谱参数值,其进行建筑物抗震设计精度和应用性高。 相似文献
157.
M. Aktar S.
zalaybey M. Ergin H. Karabulut M.-P. Bouin C. Taprdamaz F. Bimen A. Yrük M. Bouchon 《Tectonophysics》2004,391(1-4):325
We examined the spatial variation in the aftershock activity from the 17 August 1999 Izmit, Turkey earthquake. We found that this aftershock sequence is non-uniform both in space and time, aspects that need to be taken into account in any further statistical analysis. Other aspects of this aftershock sequence are similar to other aftershock sequences, namely low b-values and a high degree of spatial variation. We have detected three zones of relatively high b-values, two of which coincide with asperities revealed by previous slip inversion studies. The third zone with an anomalous b-value is located beyond the fault rupture and indicates a weakened fractured zone in the Yalova-Tuzla area. This b-value analysis provided no evidence for any significant difference that may exist between the two sides of the mainshock fault plane. 相似文献
158.
159.
分析了对流层延迟的基本特性及常用的处理措施,通过实例表明了不同对流层的处理方法对大地高精度有较大影响:当基线两端高差较大时,即使基线较短,其气象条件也有所差异,仅仅通过差分或模型改正仍不能消除对流层延迟的影响,残余的对流层延迟仍然影响大地高的解算精度,通过对残余对流层延迟进行估计能够明显改善大地高的精度。 相似文献
160.