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91.
A new earthquake catalogue for central, northern and northwestern Europe with unified Mw magnitudes, in part derived from chi-square maximum likelihood regressions, forms the basis for seismic hazard calculations
for the Lower Rhine Embayment. Uncertainties in the various input parameters are introduced, a detailed seismic zonation is
performed and a recently developed technique for maximum expected magnitude estimation is adopted and quantified. Applying
the logic tree algorithm, resulting hazard values with error estimates are obtained as fractile curves (median, 16% and 84%
fractiles and mean) plotted for pga (peak ground acceleration; median values for Cologne 0.7 and 1.2 m/s2 for probabilities of exceedence of 10% and 2%, respectively, in 50 years), 0.4 s (0.8 and 1.5 m/s2) and 1.0 s (0.3 and 0.5 m/s2) pseudoacclerations, and intensity (I0 = 6.5 and 7.2). For the ground motion parameters, rock foundation is assumed. For the area near Cologne and Aachen, maps
show the median and 84% fractile hazard for 2% probability of exceedence in 50 years based on pga (maximum median value about
1.5 m/s2), and 0.4 s (>2 m/s2) and 1.0 s (about 0.8 m/s2) pseudoaccelerations, all for rock. The pga 84% fractile map also has a maximum value above 2 m/s2 and shows similarities with the median map for 0.4 s. In all maps, the maximum values fall within the area 6.2–6.3° E and
50.8–50.9° N, i.e., east of Aachen. 相似文献
92.
Histograms of observations from spatial phenomena are often found to be more heavy-tailed than Gaussian distributions, which
makes the Gaussian random field model unsuited. A T-distributed random field model with heavy-tailed marginal probability density functions is defined. The model is a generalization
of the familiar Student-T distribution, and it may be given a Bayesian interpretation. The increased variability appears cross-realizations, contrary
to in-realizations, since all realizations are Gaussian-like with varying variance between realizations. The T-distributed random field model is analytically tractable and the conditional model is developed, which provides algorithms
for conditional simulation and prediction, so-called T-kriging. The model compares favourably with most previously defined random field models. The Gaussian random field model
appears as a special, limiting case of the T-distributed random field model. The model is particularly useful whenever multiple, sparsely sampled realizations of the
random field are available, and is clearly favourable to the Gaussian model in this case. The properties of the T-distributed random field model is demonstrated on well log observations from the Gullfaks field in the North Sea. The predictions
correspond to traditional kriging predictions, while the associated prediction variances are more representative, as they
are layer specific and include uncertainty caused by using variance estimates. 相似文献
93.
Dire financial constraints and the threats of forced structural reform have had the unforeseen effect of forcing municipal councils across Australia to reconsider their operational activities and organisational arrangements. With considerable ingenuity, numerous municipalities have proposed and sometimes adopted new structural formations that embody various forms of co-operative service provision. This remarkable development has unfortunately been largely ignored in the scholarly literature on Australian local government. In a modest effort aimed at remedying this neglect, the present paper seeks to outline the small, rural New South Wales Gilgandra Shire Council's (2004) ‘Co-operative/Local Government Service Company’ model, place it in the broader context of alternative models of local governance suitable for Australian conditions, and evaluate its characteristics. 相似文献
94.
分析了洪山预测区西部洪山岩体地质特征及其向外围扩散的范围和程度,研究了北掌勘查区和焦窑煤矿两邻区煤层受岩浆岩影响的程度,认为洪山岩体对预测区煤系及煤层赋存的影响较小,岩体外围仍有煤系赋存。为下一步找煤指明了方向。 相似文献
95.
通过对漳平市吾祠煤矿区的煤层地质构造特征分析,探讨了复杂构造条件下的矿井生产布局,主要是煤矿区段水平划分、煤炭采区的巷道布置、采煤方法及有关地质硐探等问题,对矿山开发有一定的指导意义。 相似文献
96.
Midstream of the Keelung River Basin in Northern Taiwan has become highly urbanized and densely populated area. Flood inundation
along riversides frequently occurred during typhoons or rainstorms. Three protection measures, including constructions of
high-level protection levees, a diversion channel, and a detention reservoir, were proposed for flood mitigation. The main
purpose of this study is to evaluate the flood mitigation performance of the three proposed structural measures by using combined
hydrologic analyses and hydraulic routings. A semi-distributed parallel-type linear reservoirs rainfall-runoff model was used
for estimating the surface runoff. Furthermore, a 1-D dynamic channel routing model was coupled with a two-dimensional inundation
model to simulate the hydraulic characteristics of river flooding and overland flow. Simulation results of flood stages, runoff
peak discharges, and inundation extent under design rainfall scenarios were chosen as the criteria for evaluation. The results
showed a diversion channel is superior to the other two measures for flood mitigation of the study area. After the process
of environmental impact assessment, a revised diversion channel approach has been approved for construction as the major structural
measure. 相似文献
97.
针对间歇式热处理炉温度控制对象的特性要求,提出了参数在线自调整模糊控制与智能积分相结合的一种新型模糊控制方法。该方法的基本思想是在系统误差较大时,用参数在线自调整模糊控制算法以提高系统的响应;在系统误差较小时,加入智能积分作用以消除静态误差,智能积分作用是有选择的施加积分作用,克服了一般连续积分控制的缺点。论述了带智能积分参数在线自调整模糊控制器的设计及软件实现。并且通过在MATLAB软件上的仿真分析表明该方法的合理性及可行性。 相似文献
98.
针对数据备份服务器备份性能优化问题,分别对实时数据存储与历史数据备份之间的关系、数据备份服务器所备份的数据类型非唯一性、客户数量对备份服务器备份效率的影响三方面进行初步的测试与分析,提出了通过优化数据块的选取、优化数据采集方式、优化备份策略提高备份服务器备份效率的基本方法。 相似文献
99.
基于广义Hough变换的不规则形状目标提取方法 总被引:1,自引:0,他引:1
提出了一种基于广义Hough变换的不规则形状目标的提取方法。该方法主要包括目标参数描述和目标提取两部分。实验表明,该方法精度好、效率高。 相似文献
100.
利用井田勘探和矿井生产的地质资料,对上京井阳的构造特征进行了总结,认为该井田以褶皱为主,尤以翻卷褶曲为特征,并且其复杂的构造格局是在经受了多次构造运动而形成的,其形成过程可概括为四个阶段:含煤盆地形成阶段;Ⅰ级褶皱和辗掩断层形成阶段;Ⅱ、Ⅲ级褶皱和一系列正断层形成阶段;构造体系的叠加、改造和定型阶段。 相似文献