阿拉斯加巴罗AB—67钻孔岩芯的沉积环境分析

巴罗ＡＢ－６７钻孔岩芯的４８个样品被进行了２５个项目的粒度分析和４４个项目的地球化学分析。本文对这些数据进行了Ｑ型因子分析,并得到了４个主因子。研究表明,这４个因子分别代表了沉积环境的四项指标,它们分别为沉积速率,降水,海平面和温度。从岩芯顶部５个样品与巴罗气象台观测记录研究了古温度和古降水的转换函数,从＾２１０Ｐｂ测年和几个环境事件确定了沉积速率的转换函数。     

Seismic frame design via inverse mode design of frame-ground systems

A two-step stiffness design procedure is developed for a moment-resisting planar frame supported by a prescribed two-dimensional finite-element ground-pile system. In the first step, a hybrid inverse eigenmode problem is formulated and its solution is derived in an analytical form. A difficulty resulting from the existence of multiple interface nodes is overcome by incorporating a deformation constraint into a set of linear equations for finding the lowest-mode displacements at the interface nodes and in the ground. In the second step, the fundamental natural frequency of the combined system and the lowest mode-strain ratios in the frame specified in the first step are regarded as the parameters for adjusting the mean peak seismic member-end strains to their specified values. If the fundamental natural frequency of the frame with a fixed-base happens to be close to that of the ground, a difficulty arises in the two-step stiffness design procedure because of an irregular response amplification and of the non-predominance of the lowest-mode components. A new practical design procedure of rapid convergence is proposed such that an initial design is found for a stiff ground and that a sequence of stiffness designs is generated with respect to a ground stiffness parameter without any differential coefficient of series expansion. The accuracy of the model utilized in this paper and the validity of the present stiffness design procedure are verified through time-history response analysis.     

利用不完全Cholesky共轭梯度法求解点源三维地电场

点源三维地电场的求解是一大型数值计算问题．本文用有限差分方法求解,最后形成一个线性方程组Ax＝b,这里A是大型稀疏的带状对称矩阵．解大型稀疏方程组的完全Cholesky分解直接算法,一般要求巨大的机器内存来存储系数矩阵A,而且计算速度极慢．因此引入不完全Cholesky共轭梯度（ICCG）算法及按行索引的稀疏存储模式,充分利用A的稀疏性,使得计算速度大大提高,而内存要求则大大减少,因此ICCG算法是地电三维正演的强有力工具．     

A spectrum of the acoustic-gravity waves associated with Auroral electro-jet

This model concerns the analysis of Aurora initiated travelling pressure waves in an isothermal atmosphere. Electro-dynamic Lorentz Force associated with auroral electric current density during the periods of geomagnetic activity is invoked as a possible exciting source.The dispersion phenomena in auroral induced acoustic gravity modes in the earth's atmosphere are examined and various cut-off frequencies analysed.Finally, an attempt is made to obtain a far field representation of the forced oscillations by means of Green's Function technique. Therefrom, the spectral amplitudes of the ground-level oscillations are computed. Incorporating various scaling factors, it is deduced that these amplitude components are in reasonable agreement with the results of recent measurements.     

基于主成分分析的库存管理神经网络模型研究

从影响合理库存的诸多因素中,利用数理统计的思想,找出若干主要指标,通过建立神经网络模型,进行模拟仿真,寻求一种解决问题的有效方法,把库存调整到理想的状态。     

柴达木盆地侏罗系油气成藏模式与油气聚集规律

针对柴达木盆地侏罗系油气勘探目标选择的难点,从烃源岩与圈闭时空配置的角度,建立侏罗系油气早期聚集早期成藏、早期聚集晚期成藏、晚期聚集晚期成藏3种模式。盆地油气来源、充注时期、油藏调整及破坏等方面存在规律性,这决定了油气分布的有序性,呈现出“断褶区聚气,山前、潜伏区聚油,凸起顶、凸起斜坡区油气并存”的基本格局和油气富集程度依次变好的序列。据此预测油气富集范围,从中优选冷湖4号东斜坡、乌南—巴依凸起斜坡、怀头他拉—德北斜坡、潜伏Ⅰ号等新靶区。     

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中国东海海平面长期变化与趋势研究

From the analyses of the satellite altimeter Maps of Sea Level Anomaly(MSLA) data, tidal gauge sea level data and historical sea level data, this paper investigates the long-term sea level variability in the East China Sea(ECS).Based on the correlation analysis, we calculate the correlation coefficient between tidal gauge and the closest MSLA grid point, then generate the map of correlation coefficient of the entire ECS. The results show that the satellite altimeter MSLA data is effective to observe coastal sea level variability. An important finding is that from map of correlation coefficient we can identify the Kuroshio. The existence of Kuroshio decreases the correlation between coastal and the Pacific sea level. Kurishio likes a barrier or a wall, which blocks the effect of the Pacific and the global change. Moreover, coastal sea level in the ECS is mainly associated with local systems rather than global change. In order to calculate the long-term sea level variability trend, the empirical mode decomposition(EMD) method is applied to derive the trend on each MSLA grid point in the entire ECS. According to the 2-D distribution of the trend and rising rate, the sea level on the right side of the axis of Kuroshio rise faster than in its left side. This result supports the barrier effect of Kuroshio in the ECS. For the entire ECS, the average sea level rose 45.0 mm between 1993 and 2010, with a rising rate of(2.5±0.4) mm/a which is slower than global average.The relatively slower sea level rising rate further proves that sea level rise in the ECS has less response to global change due to its own local system effect.     

疫情防控期“数字地形测量学”线上教学实践

疫情之下,在线教学为“停课不停教、停课不停学”提供了理想的教学方案。基于超星泛雅网络教学平台,以“数字地形测量学”在线课程建设为例,探索在线课程的建设方法与途径,构建“能学、辅教”的立体化教学资源,进行“超星泛雅+学习通+腾讯课堂+课程QQ群”混合教学模式的探索和实践,为在线课程建设与应用提供借鉴。