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61.
62.
岩土参数的正态分布是岩土工程可靠分析的基本假定之一。目前,岩土工程参数的正态性检验以KS (Kolmogorov-Smirnov)检验为主,然而诸多研究表明,对于小样本数据,KS检验的正态性检验结果并不可靠。本文以废黄河泛滥沉积相粉土中的孔压静力触探(CPTU)锥尖阻力qt数据为研究对象,首先采用ANOVA (方差分析)检验,从CPTU测试资料中进行总体的样本筛选,然后应用SW (Shapiro-Wilk)检验、KS检验、LF (Lilliefors)检验和AD (Anderson-Darling)检验等4种正态性检验方法,在不同样本容量条件下,对测试数据进行正态性检验评价。当测试数据的样本容量充足时,分析结果表明:SW检验结果最为严格,KS检验结果最不保守,而LF检验和AD检验的严格性介于两者之间;对于常规岩土工程设计,采用KS检验结果即可满足稳定性分析要求,对于复杂岩土工程设计,采用SW检验对设计参数进行正态性检验,可降低设计的不确定性。 相似文献
63.
基于国家台网地震速报的实际工作需求,针对国家台网在全球地震速报中缺乏专门的地名查询系统,通过对国家台网实时、人机交互处理子系统和全国速报信息交换平台(EQIM系统)的相关协议和数据接口进行研究,并结合地震速报相关规定中对地名的要求,基于地理信息系统Arc GIS提供的Arc GIS Engine(AE)组件技术,采用Visual.Net开发平台和COM组件技术,来实现获取地震地名信息的功能,开发设计一套用于国家台网地震速报的地名查询辅助系统,希望可以有效提高国家台网地震速报的效率和准确度。 相似文献
64.
本文通过对秦巴陕、甘、川、豫、鄂五省已知砂金矿床资料的整理和综合,简要的总结了区内砂金矿床的成因,形态类型,不同类型砂金矿床的地质特征及砂金矿的富集规律。对砂金矿的普查找矿工作有一定的指导意义。 相似文献
65.
Wang Xiutong Xu Hui Nan Youbo Sun Xin Duan Jizhou Huang Yanliang Hou Baorong 《中国海洋湖沼学报》2020,38(4):1018-1044
Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO_2) is the most widely used photoanode.This review summarizes the progress in TiO_2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO_2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection. 相似文献
66.
Boussinesq’s theory was used in this study on water waves entering shallow water showing that the spacial variation of the
wave amplitude is nonlinear, and is governed by the Duffing equation usually applied to describe nonlinear oscillation in
nature.
Contribution No. 3324 from the Institute of Oceanology, Chinese Academy of Sciences.
Project 49471276 supported by NSFC and the Ninth-Five-Year Key Project (KI952-s1-420) of the Chinese Academy of Sciences. 相似文献
67.
Corrosion behavior of steel in the juncture area of sea clay and sand was studied. The results show that galvanic corrosion occurred between steel samples buried in sea clay and sand, and that the polarity of the galvanic cell reversed after some testing later. The cause of reversing of polarity is discussed. 相似文献
68.
69.
Analysis of ERS-2 scatterometer winds and wind-wave calculation for eastern China seas 总被引:1,自引:0,他引:1
The wind system over the China seas plays an important role in climate variation there. In this paper, ERS-2 scatterometer winds covering the period of 1998 and the area of 25-41°N, 117-130°E were analyzed and compared to NCEP winds and buoy winds in the same period and location, to assess how well the ERS-2 data reflect the real wind regime, at least for this area. The results indicated that ERS-2 scatterometer winds are closer to buoy observations than NCEP winds. In addition, a new wind-wave growth relation was applied to calculate wave parameters. 相似文献
70.
Based on in-situ observation, satellite and reanalysis data, responses of the western North Pacific subtropical ocean(WNPSO) to the slow-moving category 5 super typhoon Nanmadol in 2011 are analyzed. The dynamical response is dominated by near-inertial currents and Ekman currents with maximum amplitude of 0.39 m/s and 0.15 m/s, respectively. The near-inertial currents concentrated around 100 m below the sea surface and had an e-folding timescale of 4 days. The near-inertial energy propagated both upward and downward, and the vertical phase speed and wavelength were estimated to be 5 m/h and 175 m, respectively. The frequency of the near-inertial currents was blue-shifted near the surface and redshifted in ocean interior which may relate to wave propagation and/or background vorticity. The resultant surface cooling reaches -4.35℃ and happens when translation speed of Nanmadol is smaller than 3.0 m/s.When Nanmadol reaches super typhoon intensity, the cooling is less than 3.0℃ suggesting that the typhoon translation speed plays important roles as well as typhoon intensity in surface cooling. Upwelling induced by the slow-moving typhoon wind leads to typhoon track confined cooling area and the right-hand bias of cooling is slight. The mixed layer cooling and thermocline warming are induced by wind-generated upwelling and vertical entrainment. Vertical entrainment also led to mixed layer salinity increase and thermocline salinity decrease, however, mixed layer salinity decrease occurs at certain stations as well. Our results suggest that typhoon translation speed is a vital factor responsible for the oceanic thermohaline and dynamical responses, and the small Mach number(slow typhoon translation speed) facilitate development of Ekman current and upwelling. 相似文献