Study on General Performance of Jack-up Under Elevated Condition

Method of checking for jack-up elevated performance including leg structure strength, fixation system or jacking system bearing capacity, pre-load requirements, spud can bearing capacity and overturning stability is suggested in this paper. As an example, a jack-up with truss legs is analyzed by finite element analysis method. This paper may be helpful to the rig owners, operators and designers.     

赣南天门山-红桃岭钨锡矿田成岩成矿时代精细测定及其地质意义

素有“世界钨都”美誉的赣南产有密集的与花岗岩类侵入体密切相关的钨锡多金属矿床,然而,目前对钨锡成矿和花岗岩成岩年龄还缺乏很好的约束。本文以天门山-红桃岭钨锡矿田为对象,在详细的矿田地质调查和典型矿床解剖基础之上,采用高精度测年技术开展了成岩成矿年代学研究。利用锆石SHRIMPU-Pb法,分别获得天门山似斑状黑云母二长花岗岩体和红桃岭黑云母花岗岩体成岩年龄分别为151.8±2.9Ma(n=14,MSWD=1.3)和151.4±3.1Ma(n=11,MSWD=0.34);利用辉钼矿Re-Os等时线法,分别获得牛岭内带石英脉型和樟斗外带石英脉型钨矿成矿年龄分别为154.9±4.1~154.6±9.7Ma和149.1±7.1Ma(n=6,MSWD=1.3)。可见,本区钨矿床成矿和与之有密切成因关系的花岗岩成岩年龄限定在晚侏罗世,对应于区域华南中生代第二次大规模成矿作用,钨成矿与花岗岩成岩基本不存在时差。     

Correlation Between Total Lightning Activity and Precipitation Particle Characteristics Observed from 34 Thunderstorms

A total of 34 thunderstorms around Shanghai and Wuhan of China are analyzed in order to determine the relationship between total lightning activity and precipitation particle characteristics.Precipitation particle concentration data are obtained from the 2A12 product of TRMM/TMI(Tropical Rainfall Measuring Mission/TRMM Microwave Image) and lightning activity data are from the TRMM/LIS(Lightning Imaging Sensor) and SAFIR3000(Surveillance et Alerte Founder par Interferometric Radioelectirque).On a spatial ...     

The Ground Deformation Disaster in the City of Tianjin Associated with the Tangshan Earthquake

In this paper,a study of the principal characteristics of the ground deformation disasters in the city of Tianjin caused by the Tangshan earthquake is based on the results from the recent remeasurements of the geodetic controlling network of Tianjin and from on-site investigations after the earthquake.These results show that only the ground deformation in the Ninghe and Hangu areas near the epicenter reflect directly the co-seismic crustal stress,while the serious ground deformation and the engineering earthquake damages in the urban districts of Tianjin are controlled to a great extent by the local engineering geological structures,showing a kind of secondary disaster.Several suggestions are also proposed in the paper concerning the counter-measures for reducing the earthquake damage in big cities.     

The Mathematic Models of the Kalman Filtering for Across-Fault Measurement

This paper makes a probe into the application of the Kalman filtering method to the data processing of across-fault measurements.On the basis of statistical regression,the mathematic and stochastic models of filtration are established by combining the regression method with Kalman filtering.In the filtering computation,not only the randomness of fault movements but also the time-dependent variation of environmental effects have been taken into consideration.By use of the adaptive filtering method,an estimation of the dynamic noise variance matrix is obtained through iteration.Models for one measuring line(leveling line or baseline),two measuring lines(both leveling lines or both baselines)and four measuring lines(two leveling lines and two baselines)are derived and established systematically.By means of these models,the data of across-fault measurements can be processed dynamically in real-time to provide the filtered values of height difference between benchmarks or baseline length at different time in     

SHORT COMMUNICATION COMMENTS ON THE RESIDUAL BILINEARIZATION METHOD

Through theoretical analysis and computer simulation,this short communication comments on theresidual bilinearization(RBL)method and compares it with non-bilinear rank annihilation(NBRA)forthe treatment of second-order calibration with non-bilinear data.It is found that these two methods aremathematically equivalent but have different noise propagation properties.The second-order advantage,namely quantitation in the presence of unknown interferences,can be carried over to non-bilinear dataonly if there exists a net analyte rank(NAR)for the analyte of interest.     

IAP GCM模式大气背景环流在厄尔尼诺年的异常

本文分析了中国科学院大气物理研究所大气环流模式(IAP GCM)模式大气5～9月平均环流(本文称为背景环流)。结果表明;厄尔尼诺年一系列重要系统(南方涛动、瓦克环流、哈德莱环流、西太平洋副热带高压和热带辐合带)及大范围降水均发生明显异常;北半球西太平洋热带、副热带是环流异常的主要区域。它们与观测资料的分析结果基本一致,从而论证了该模式在低纬环流研究中的应用前景。     

NUMERICAL EXPERIMENT OF THE INFLUENCES OF HEAT AND WIND STRESS ON THE EQUATORIAL OCEAN CIRCULATION

A time-dependent linear model on the equatorial beta plane is developed in this paper.Its verticalstructure consists of two active layers with equal density and temperature above the thermocline and aquasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean ismuch smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibriumand anomalous development of the ocean-almosphere circulation.     

THERMODYNAMIC PROPERTIES AND ROLE OF THERMALS IN THE STRATUS-TOPPED BOUNDARY LAYER

From results of two large-eddy simulation of stratus-topped boundary layer,the structure,thermodynamic prop-erties and role of thermals are investigated by using conditional sampling methods,which divided the thermals into thewarm/moist,cool/dry,warm/dry and cool/moist events.The results show that the main turbulent circulation in thestratus-topped boundary layer is composed of the warm/moist updraft and cool/dry downdraft.Below entrainmentregion,the warm/moist updrafts and cool/dry downdrafts are,respectively,positively and negatively buoyant andcontribute most to total fluxes and variances.Evaporative cooling has important effect on the structure and thermodynamic properties of thermals instratus-topped boundary layer.     

模拟地震的弹簧滑块模型的混沌运动

我们构造了一种自由度为２的双弹簧滑块系统，讨论模型参数的不均匀性和滑块间的相互作用与复杂现象的关系。假定滑块在所受力小于其静摩擦力时保持静止，因此，只有发生了滑动，两滑块所受力之差才改变。如果我们以两滑块受力之差为变量，就可以构造一种一维的映射。这种映射直观地显示了系统的演化，反映了方程终态解的形态。结果表明，用混沌运动来描述地震现象可能是较为合理的。