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991.
Yu Wang Zijun Cao 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2016,10(4):251-268
In site investigation, the amount of observation data obtained for geotechnical property characterisation is often too sparse to obtain meaningful statistics and probability distributions of geotechnical properties. To address this problem, a Bayesian equivalent sample method was recently developed. This paper aims to generalize the Bayesian equivalent sample method to various geotechnical properties, when measured by different direct or indirect test procedures, and to implement the generalized method in Excel by developing an Excel VBA program called Bayesian Equivalent Sample Toolkit (BEST). The BEST program makes it possible for practitioners to apply the Bayesian equivalent sample method without being compromised by sophisticated algorithms in probability, statistics and simulation. The program is demonstrated and validated through examples of soil and rock property characterisations. 相似文献
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Grateloupia ramosa Wang & Luan sp. nov. (Halymeniaceae, Rhodophyta) is newly described from Hainan Province, southern China. The organism has the following morphological features: (1) purplish red, cartilaginous and lubricous thalli 5–10 cm in height; (2) compressed percurrent axes bearing abundant branches with opposite arrangement; (3) claw-like apices on top, constricted to 2–4 cm at the base; (4) cortex consisting of 3–6 layers of elliptical or anomalous cells and a medulla covered by compact medullary filaments; (5) reproductive structures distributed throughout the thallus, especially centralized at the bottom of the end portion of the branches; and (6) 4-celled Carpogonial branches and 3-celled auxiliary-cell branches, both of the Grateloupia-type. The morphological diff erences were supported by molecular phylogenetics based on ribulose-1, 5-bisphosphate carboxylase/oxygenase (rbcL) gene sequence analysis. There was only a 1 bp divergence between specimens collected from Wenchang and Lingshui of Hainan province. The new species was embedded in the large Grateloupia clade of the Halymeniaceae. The pairwise distances between G. ramosa and other species within Grateloupia ranged from 26 to 105 bp, within pairwise distances of 13–111 bp between species of the large genus Grateloupia in Halymeniaceae. Thus, we propose this new species as G. ramosa Wang & Luan sp. nov. 相似文献
998.
针对影像分割所需区域内部满足一致性、区域间互不相交的要求,鉴于高光谱影像地物在尺寸、形状、光谱上的异质性,开展高光谱影像分割研究。应用视觉皮层细胞神经元之间存在的局部兴奋全局抑制振荡网络对视觉影像信息进行深入提取和处理,在此基础上,结合小世界神经网络高群集系数、短特征路长的特点,研究了LEGION神经元振荡器所具有的小世界神经网络的同步性能,从而构建了耦合小世界网络的LEGION分割算法。进一步采用直观参数设置,简化高微分方程的计算复杂,减少迭代次数。实验表明:耦合小世界网络的LEGION分割算法,可有效地把高光谱影像中同质地物分割在一起,达到信息提取的目的。 相似文献
999.
辽宁省城市竞争力重心时空迁移分析 总被引:2,自引:0,他引:2
针对辽宁省14个城市竞争力的发展特点和时空迁移变化规律的问题,该文借助于城市竞争力评价指标体系,得到了辽宁省14年来14个地级市的城市竞争力水平,基于区域重心模型,得到2001—2014年城市各项竞争力重心的动态迁移轨迹,并对其进行对比分析。结果表明:辽宁省14个城市的竞争力水平不均衡,城市综合实力差异明显;辽宁省14个城市的经济发展竞争力重心和环境发展竞争力重心呈现向东北方向偏移的趋势,社会发展竞争力重心呈现出向南发展的趋势,社会发展水平滞后于经济和环境发展水平;城市竞争力重心迁移是一个时期城市群发展影响因素的具体体现,社会发展需要同经济发展、环境发展协调进行,才能提升城市综合竞争实力。 相似文献
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The lower Cambrian develops a set of organic-rich black shales in Yangtze Platform and is regarded as one of the key layers of shale gas exploration. The microscope pore structure characteristics and methane sorption capacity were investigated using scanning electron microscope, nitrogen adsorption and methane sorption experiments, and then their controlling factors combining with organic matter, mineral compositions were discussed for Niutitang shales in Zunyi area, Mufushan shales in Nanjing area and Huangboling shales in Chizhou area. The results show as below; ( I ) The pores in lower Cambrian shales are mainly dominated by organic pores, interlayer pores in clay minerals and micro-fractures, as well as containing some intergranular pores between brittle mineral grains, honeycomb poies formed by pyrite crystals falling out, and dissolution molds in fossils; ( 2) DKT pore size distributions show the pores is mainly concentrated in the range of less than 4 nm in lower Cambrian shales and kerogens, while a certain amount of pores are above 4 nm are also existed in lower Cambrian shales, which may be contributed by smectite; ( 3)The specific surface area, pore volume and Langmuir methane sorption capacity of the lower Cambrian shales are ranging from 5.58 to 31. 96 inVg, 0.026 to 0.088 mL/g and 1.36 to 5. 3 mL/g, respectively, which are mainly controlled by TOC and smectite contents, but the effect of TOC and smectite on physical properties are quite different for the lower Cambrian shales in different regions; ( 4)The specific surface area of two Niutitang kerogens are 7. 08 and 7. 92 times than that of the shales and methane sorp-Tion capacity of kerogens arc 5.81 and 7.09 times than that of the shales, suggesting that kerogen is a main carrier of methane gas occurrence in. 相似文献