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61.
有序样品聚类的最优分割应用程序开发 总被引:2,自引:0,他引:2
在地层划分、蚀变、矿化、圈定矿体的研究中,有序样品聚类的最优分割法——数学处理方法是一个十分有效的方法,而该方法的数据处理是一个复杂而繁琐的过程。为了有志于地质研究的爱好者,根据最优分割的数学处理原理,将最优分割法编制成易于为非计算机专业人员所利用的处理软件,并免费共享。该程序使用方便,操作简单,只要按文中说明加以编辑,即可投入使用。 相似文献
62.
This paper proposes an interpolation method based on a modified Kohonen artificial neural network, and is used to interpolate
marine gravity data on a regular grid. This method combines accuracy comparable to that of kriging with a much shorter computing
time than kriging. It is particularly efficient when both the size of the grid and the quantity of available data are large.
Under some hypotheses similar to those of kriging with a trend, the unbiasedness and optimality of the method can be demonstrated.
Comparison with kriging with a trend using marine gravity data shows similar results. Although neural interpolation is slightly
less efficient, it is more robust outside of the marine data area. 相似文献
63.
The Arab countries cover a large portion of the African and Arabian plates, a region characterized by seismic activity along complex continental collision zones, active seafloor spreading, rifting, and intraplate earthquakes. Establishing a standardized regional seismic network in these countries, then, is of great importance. Considerable effort of some Arab countries and UNESCO under project PAMERAR is under way to achieve this goal. A design for the spatial distribution of a regional seismic network in the area, based on a D-optimal planning criterion, is proposed in this paper. The method, which involves optimizing the geographical locations of stations, is based on the probability of earthquake occurrence at a given point in the seismic region, travel times of seismic waves, and minimization of the ellipsoid volume of earthquake location errors. 相似文献
64.
65.
应用中科院大气物理研究所建立的三维雹云模式,对河南南阳1999年5月9日一次降雹过程进行了数值模拟,模拟结果表明:云内存在过冷水累积区,冰雹在过冷水累积区长大;使用不同催化方案催化后,均能起到减少地面降雹的作用,但是在雹云形成的不同时间、不同的催化部位和使用不同的催化剂量,其消雹效果不一样,在冰雹形成前于过冷水累积区催化效果最好。 相似文献
66.
1 INTRODUCTION Odgaard and Kennedy (1983) suggested that for values of angle of attack, α greater than or equal to approximately 20o, a persistent scour hole is produced near the upstream end of a vane. As α was reduced the number of vanes producing obj… 相似文献
67.
本文应用“最优分割法”,分别对汾渭地震带及晋陕豫交界区的地震活动进行了分期,并对结果进行了讨论。 相似文献
68.
有限差分方法(Finite-difference Method, FD)广泛用于地震波场数值模拟, 但其存在固有的数值频散问题, 影响模拟的计算效率和数值精度.本文主要研究了有限差分方法的空间数值频散误差和网格划分精度以及差分算子的关系, 基于计算量最小准则, 提出了最优化有限差分参数选取流程, 为有限差分数值模拟参数选取提供理论指导.本文主要工作包括: (1) 提出了空间数值频散正变换过程(Forward Space Dispersion Transform, FSDT)方法, 该方法可以高效模拟出不同网格划分精度(波长采样点数)的带有空间数值频散的波场; (2) 提出了波场空间数值频散误差衡量准则, 可以定量地判断出数值模拟导致的波形频散程度, 选取合适的频散误差阈值; (3) 研究了给定空间数值频散误差阈值下, 差分算子系数、差分算子阶数、网格划分精度与计算量之间的关系.文中基于雷米兹交换方法(Remez Exchange Method, RE)和泰勒级数展开方法(Taylor-series Expansion Method, TE)的差分系数, 在空间数值频散误差阈值0.01时, 数值模拟了不同差分算子阶数、网格划分精度与计算量的关系, 并给出了有限差分参数选取的参考值.
相似文献69.
Reactive contaminant transport models are used by hydrologists to simulate and study the migration and fate of industrial waste in subsurface aquifers. Accurate transport modeling of such waste requires clear understanding of the system’s parameters, such as sorption and biodegradation. In this study, we present an efficient sequential data assimilation scheme that computes accurate estimates of aquifer contamination and spatially variable sorption coefficients. This assimilation scheme is based on a hybrid formulation of the ensemble Kalman filter (EnKF) and optimal interpolation (OI) in which solute concentration measurements are assimilated via a recursive dual estimation of sorption coefficients and contaminant state variables. This hybrid EnKF-OI scheme is used to mitigate background covariance limitations due to ensemble under-sampling and neglected model errors. Numerical experiments are conducted with a two-dimensional synthetic aquifer in which cobalt-60, a radioactive contaminant, is leached in a saturated heterogeneous clayey sandstone zone. Assimilation experiments are investigated under different settings and sources of model and observational errors. Simulation results demonstrate that the proposed hybrid EnKF-OI scheme successfully recovers both the contaminant and the sorption rate and reduces their uncertainties. Sensitivity analyses also suggest that the adaptive hybrid scheme remains effective with small ensembles, allowing to reduce the ensemble size by up to 80% with respect to the standard EnKF scheme. 相似文献
70.
The terrain of Inner Mongolia is long and narrow, and the geological structure is complicated. The South China crustal velocity model and Inner Mongolias optimal crustal velocity model 2015 cannot fully meet the earthquake location requirements of Inner Mongolia. Based on the seismological observations produced by Inner Mongolia Seismic Digital Network from 2009 to 2016,the initial model was obtained by using the linear fit of the seismic phases and the converted travel time curve. The Hyposat results of 225 earthquakes that occurred in western Inner Mongolia were scanned using this model,and the velocity model for western Inner Mongolia was determined as follows: V1= 6. 06 km/s;VPb= 6. 61 km/s; Vn= 8. 12 km/s; H1= 30 m; and the Moho depth H = 44 km. Comparison of the test results of the new model and the reference model shows that the residual error of the new model and the mean deviation of the epicenter location have obviously decreased. 相似文献