数字影像中角点与直线的高精度定位算子   总被引：8，自引：0，他引：8  

张剑清  张祖勋 《测绘学报》1994,23(2):98-106

本文在分析现有数定影像定位算子的基础上，提出了精确定位数字影像中角点与直线的高精度定位算子。这种算子通过精确定组成角点的两条直线，从而精确定位角点。实验表明，新的定位算子有很高的定位精度，在理想情况下，新定位算子的精度可达０．０２像素，最后，客种算子被用于数字影像的相对定向，取得了令人满意的结果。  相似文献   

塔克拉玛干沙漠中的古河道与地下水     

张鸿义  许风林 《新疆地质》1994,(3)

塔克拉玛干沙漠中发育有众多的古河道，其密集区主要集中在大沙漠中部。不同河流的古河道，含水层岩性有明显差异，地下水的富水性也明显不同。但沿古河道，地下水富水性均较两侧好，水质也相对较好，多为淡水和微咸水，为在沙漠区寻找水资源提供了方向  相似文献   

线性规划在徐州地下水资源开发中的应用   总被引：1，自引：0，他引：1  

陈爱光  陈国富 《地球科学》1985,(1)

本文从地下水系统的观点出发,对徐州地区中寒武统—中奥陶统碳酸盐岩地下水系统进行了分析。并应用线性规划的原理和方法对徐州市西郊四个水源地地下水进行了水文地质计算。在规定水位允许降深的约束条件下,求得至2000年,该区地下水最大开采量为14万米~3/天及各水源地相应取水量的最佳分配。文中采用特定条件图解法计算多边界、多主井抽水干扰影响的方法,具有通用意义。  相似文献   

离子刻蚀全息光栅的研究     

沈邦兴  李开新  张谊萍 《武汉大学学报(信息科学版)》1987,(1)

利用国产的光刻胶和国产离子刻蚀机在蒸镀的铝基衬底上进行刻蚀全息光栅,在国内是一项较新的技术。本文介绍和论述了该试验工作的工艺过程、参数计算和测试方法,得出了试验结果和参数计算值基本吻合的结论,并指出了进一步改善质量的方向。  相似文献   

Cloud tracking using satellite data for predicting the probability of heavy rainfall events in the Mediterranean area     

L. Lanza  M. Conti 《Surveys in Geophysics》1995,16(2):163-181

The use of cloud tracking techniques and storm identification procedures is proposed in this paper with the aim of predicting the evolution of cloud entities associated with the highest rainfall probability within a given meteorological scenario. Suitable algorithms for this kind of analysis are based on the processing of digital images in the thermal infrared (IR) band from geostationary satellites: a selection of such algorithms is described in some detail together with a few real case applications. Three heavy rainfall events have been selected for this purpose with reference to the extreme meteorological situation observed during Fall 1992 and 1993 over the Mediterranean area. A window from 30 to 60 °N and from 20 °W to 30 °E has been identified for the analysis of data from the radiometer on board the ESA Meteosat platform. In conclusion, the suitability of cloud tracking techniques for predicting the probability of heavy rainfall events is discussed provided that the former are associated with proper modeling of small scale rainfall distribution.  相似文献   

应变能释放随时间变化的聚类方法研究     

许俊奇 《地震研究》1995,18(2):183-187

由于线性回归模型应用的广泛性，本文设定样品集的趋势是线性的，在用最优分割法对地震活动性类研究的基础上引进线性模型，扩大了最优分割法在地震活动性分类中的应用，将降类问题与建模问题有机地结合起来，去揭示地震活动性中的某种内在规律，这对于探索地震预报，研究地震发生的规律性有一定的实际意义。  相似文献   

岩(矿)石中真实矿物组成的计算及矿物化学成分的初步逼近   总被引：2，自引：0，他引：2  

林文蔚 《岩石学报》1987,3(2)

本文基于线性规划的数学模型,利用岩(矿)石化学分析资料,佐以矿物相的鉴定结果,能准确计算出岩(矿)石中真实矿物组成。在没有矿物化学成分分析数据的情况下,通过迭代、逼进,能同时给出岩矿石的真实矿物组成及矿物化学成分的逼近值,若进一步结合矿物晶体化学原理进行修正,可得出更为准确的结果。线性规划的数学模型还能应用于矿物端员组成的计算,天然及人工系统的物理化学平衡、岩石学混合计算等各个方面。  相似文献   

Simulation-optimization approach to assess groundwater availability in Refugio County, TX   总被引：10，自引：0，他引：10  

V. Uddameri  M. Kuchanur 《Environmental Geology》2007,51(6):921-929

Sustainable management of groundwater resources is critical for viable development of semi-arid regions. Refugio County, TX, is predominantly a rural community that is in close proximity to two large urban areas of Corpus Christi and San Antonio. Large-scale water supply projects are being planned to export surplus water available in Refugio County to nearby growing cities. Being a coastal county with several sensitive bays and estuaries, these projects have caused concerns with regard to decreases in freshwater inflows to coastal bodies and raised the possibility of saltwater intrusion. A simulation model characterizing groundwater flow in the shallower unconfined and the deeper semi-confined formations of the Gulf coast aquifer was calibrated and evaluated. The model results were used in conjunction with a mathematical programming scheme to estimate maximum available groundwater in the county. Stakeholder concerns were incorporated as constraints, which included prevention of saltwater intrusion in the aquifer, limiting the amount of allowable drawdown in shallow aquifers, as well as maintaining current flow gradients especially near baseflow-dependent streams and rivers. For the conditions assumed in this study, the model results indicate that roughly 4.93 × 10⁷ m³ of water can be extracted in a typical year. The management model was noted to be very sensitive to the imposed saltwater intrusion constraint.  相似文献   

基于线弹性位错模型反演1997年西藏玛尼M_w7.5级地震的干涉雷达同震形变场——Ⅱ滑动分布反演          下载免费PDF全文

孙建宝;  石耀霖;  沈正康;  徐锡伟;  梁芳; 《地球物理学报》2007,50(5)

1997年11月8日西藏M_w7.5级玛尼地震是干涉雷达技术应用于地震观测以来的一次重要事件.在第一部分中，我们应用广泛使用的Okada线弹性位错模型，假设断层的各个分段滑动量均匀，反演得到断层各个分段的几何参数和均匀滑动量.本部分的反演进一步去除滑动均匀假设，并利用更能反映断层真实状态的角形元位错模型（线弹性），在第一部分反演得到断层几何的基础上，反演断层面的静态位错分布.反演结果表明，线弹性滑动分布模型能够更好地解释观测数据，进一步提高反演的数据拟合程度.最终得到了断层面上的走滑和倾滑位错分布.首次得到的断层面滑动分布显示断层面滑动在浅部（0～12 km）比较集中，地震破裂长度约170 km，最大左旋走滑位移达4.8 m；反演结果还表明局部段落存在较大倾滑位移，量值达到1.9 m，这在断层模型中是不能忽略的，它可能是断层两侧形变不对称的原因之一；反演得到的标量地震矩为2.18×10²⁰ N·m，相当于矩震级M_w7.5，与Velasco等利用地震波形反演得到的结果一致.  相似文献   

Integral inversion of SST data of type GRACE     

P. Novák 《Studia Geophysica et Geodaetica》2007,51(3):351-367

Satellite missions CHAMP and GRACE dedicated to global mapping of the Earth’s gravity field yield accurate satellite-to-satellite tracking (SST) data used for recovery of global geopotential models usually in a form of a finite set of Stokes’s coefficients. The US-German Gravity Recovery And Climate Experiment (GRACE) yields SST data in both the high-low and low-low mode. Observed satellite positions and changes in the intersatellite range can be inverted through the Newtonian equation of motion into values of the unknown geopotential. The geopotential is usually approximated in observation equations by a truncated harmonic series with unknown coefficients. An alternative approach based on integral inversion of the SST data of type GRACE into discrete values of the geopotential at a geocentric sphere is discussed in this article. In this approach, observation equations have a form of Green’s surface integrals with scalar-valued integral kernels. Despite their higher complexity, the kernel functions exhibit features typical for other integral kernels used in geodesy for inversion of gravity field data. The two approaches are discussed and compared based on their relative advantages and intended applications. The combination of heterogeneous gravity data through integral equations is also outlined in the article. panovak@kma.zcu.cz  相似文献