Derivative of Kaula's inclination function

The derivative of Kaula's inclination function is expressed as a linear combination of two inclination functions themselves.On leave from Institute of Applied Astronomy, 197042 St.-Petersburg, Russia.     

欧洲LEP离子对撞机的稳定性分析

介绍加速器的整体稳定性分析的过程和方法，就是利用每年一度的加速器的水准测量所得的垂直偏差来分析加速器和隧道的稳定性，整个分析过程分为四个阶段：1）数据的筛选和恢复；2）建立一种不受数据处理基准和其它不确定因素影响的且能精确反映。加速器变形的技术；3）建立一种能区分加速器变形和隧道变形的技术；4）对其变形进行分析和描述。     

A detailed palaeointensity and inclination record from drill core SOH1 on Hawaii

A new record of absolute palaeointensity was obtained from drill core Scientific Observation Hole 1 (SOH1) on Kilauea volcano, Hawaii. Kilauea’s high eruption rate resulted in a relatively continuous record and stratigraphic constraints preserved the chronological order. Three hundred and sixty samples were studied with the Thellier-Thellier technique, which gave 195 successful palaeointensity and 271 successful inclination determinations. Three geomagnetic excursions were observed, which exhibited intensity reductions of about 50%. Initial age control from K-Ar and Ar/Ar dating only constrained the total age between 20 and 120 ka. The final age model was obtained by stretching the SOH1 record relative to other Hawaiian palaeomagnetic data. This gave an age range of 0-45 ka for the flows and identified the excursions as the Hilina Pali, Mono Lake and Laschamp events. The SOH1 record of the Hilina Pali event is the most detailed ever, incorporating data from around 40 flows. This age model suggests that Kilauea had a burst of activity at the SOH1 site around 20 ka. All available data was combined to form a composite record of palaeointensity and inclination on Hawaii for 0-45 ka.     

无人机三维航迹规划改进方法

在地形起伏的复杂环境下进行遥感观测任务需要进行三维航迹规划以适应多变的自然环境,而且在规划航迹时需要考虑减少飞行时间和能量消耗以提高作业效率。本文提出了一种曲面趋平化算法（CSFA）,首先采用准均匀B样条曲面拟合算法对CSFA算法处理后的目标区域DEM进行插值,构建区域的自然环境地形模型;然后为了减少时间和能量的消耗,采用点边式宽度算法计算最优飞行方向,获得最少转弯次数;最后通过摄影测量中的重叠度约束和区域环境地形模型计算三维航带和曝光点。试验通过在不同的航高下建立约束进行三维航迹规划模拟仿真,试验结果表明,本文提出的方法能够缩短航带长度,降低作业能耗,有效地提高了观测任务效率。     

大都市现代服务业空间组织机理研究——以南京为例

在工业化后期或后工业化社会,现代服务业发展水平是反映城市综合竞争力和现代化程度的主要参照。20世纪中期以来,纽约、伦敦、东京、芝加哥等国际发达城市随着低端制造业向发展中国家转移,现代服务业已发展成为其经济主体,大大提高了在全球城市体系中的地位。目前,国内外对现代服务业空间发展的一般性规律研究较多,但是鉴于中西方发展模式性差异,尚需结合我国大都市发展的现实,对现代服务业空间组织模式和布局机制作更深入研究。本文对国内外现代服务业相关研究进行了综述,在此基础上,将现代服务业空间组织机理归纳总结为自组织创新网络、市场和制度双驱动、人文和社会因素介入等,然后以南京为实证,定性与定量相结合,深入分析其现代服务业空间布局特征,并对上述机理进行了验证,以期为相关产业规划理论和方法的完善提供参考和借鉴。本文认为,在我国现行管理体制下,“自上而下”和“自下而上”相结合的现代服务业发展路径和动力机制研究应成为今后研究的重要方向。     

Stochastic nature of three dimensional bursting events and sediment entrainment in vortex chamber

In this study, three dimensional quadrant analysis of bursting process was used to recognize the susceptible regions for sediment entrainment and deposition at the bed of a vortex chamber. From the analysis, it was found that two dimensional quadrant analysis in unable to find the turbulent coherent structure of flow near the bed of the vortex chamber. Therefore, a new method based on three dimensional bursting process is introduced in this study to define the turbulent flow structure. Based on the new methodology in this study, the bursting event is divided into eight different cube zones according to three dimensional velocity fluctuations. It was realized that, four cube zones interactions are toward the central orifice of the vortex chamber and four cube zones interactions are toward the wall of the chamber and they are categorized as classes A and B, respectively. The results from the experiments showed that in class A, the internal sweep events (class IV-A) moves the settled sediment particles toward the central orifice of the chamber, whereas in class B the external sweep events (class IV-B) moves the settled sediment particles toward the external region of the chamber. Also the transition probabilities of the bursting events in 64 particular movements were determined. The result showed that stable organizations of each class of the events had highest transition probabilities whereas cross organizations had lowest transition probabilities. Additionally, an effort was made to find the average inclination angle of the three dimensional bursting events in each cube zone. The results showed that near the bed of the vortex chamber by increasing the tangential velocity toward the center of the chamber, the average inclination angle of the events in the cube zones decreased. Also, at the region where the sediment particles were deposited, the inclination angles had higher values.     

The 100-kyr ice-age cycle: internal oscillation or inclinational forcing?

The ice-age hypothesis of Muller and MacDonald (1995, 1997a, 1997b) has two parts: (a) The 100-kyr cycle does not owe its existence to Milankovitch forcing; and (b) variations in inclination of Earth's orbit (i.e., the orbit's angle with the solar system invariable plane) provide the mechanism sought. In support of the first proposition, Muller and MacDonald point to the paradox that the spectrum of oxygen isotope series from deep-sea sediments contains no power for two prominent eccentricity cycles, 125 and 400 kyr. In support of the second proposition, they offer a match between the SPECMAP record (Imbrie et al. 1984) and a plot of the amplitude of orbital inclination, shifted by 33 kyr. The hypothesis of Muller and MacDonald is rejected in both parts, although an influence of inclination forcing is not precluded entirely. The paradox of the missing eccentricity cycles (125 and 400 kyr) is explained by suppression of the two longer cycles, and enhancement of the one near 96 kyr, as a result of internal oscillation. A Muller–MacDonald machine for making the 100-kyr ice-age cycles, however conceived, would have to have a memory near 30 kyr to provide for phase shift between input and output. Precisely this amount of memory is sufficient to produce the needed oscillation in Milankovitch machine here applied; thus, there is no advantage, from the point of view of either necessity or simplicity, in replacing Milankovitch forcing, with its precise phasing (despite the fuzzy physics), with inclination forcing, and with its severe problems in phasing (and, thus far, no physics at all). Received: 10 June 1998 / Accepted: 2 February 1999     

羌塘盆地磁倾角浅化校正及其在构造上的应用——中侏罗纪以来约1 000 km的南北向缩短

古地磁磁倾角是古纬度的记录者,能真实反映块体在地质时期的古纬度,对块体构造活动有着很好的揭示作用。但最近众多的研究表明,沉积物所记录的磁倾角结果,往往存在浅化现象。因此,如何精确确定古地磁磁倾角方向,是研究块体南北向构造活动的关键。本文围绕古地磁研究相对薄弱的青藏高原腹地羌塘块体,针对雁石坪地区侏罗纪沉积地层开展了精细的古地磁研究,确定了雁石坪群沉积岩地层中灰岩和碎屑岩的剩磁方向(碎屑岩雀莫错组D_s=339.0°,I_s=24.4°,α₉₅=18.3°,灰岩布曲组D_s=336.9°,I_s=30.9°,α₉₅=7.8°),通过运用"E/I"统计方法对所获得的古地磁结果进行校正,发现雁石坪地区侏罗纪沉积岩由同沉积期间或沉积后的压实作用所造成的磁倾角浅化约5.7°～8.5°。该结果表明,羌塘块体在中侏罗世雀莫错组和布曲组期间存在约278 km北向漂移。校正后的古地磁结果,与同期的相邻块体塔里木极对比,揭示出磁倾角具有额外10.9°～14.6° 的浅化,可能指示了自中侏罗世以来,羌塘块体相对塔里木块体有约1 000 km的北向漂移和缩短。     

基于高精度地层倾角线性反演的地震全体积拉平方法

地震数据的拉平分析是三维地震资料解释中的常见方法,一般通过拾取某一标准层位并将其校正到一个基准面的方式拉平地震数据,这样会导致距离标准层越远的层位拉平效果越差.近几年发展起来的三维地震数据全体积拉平方法是避免这种拉平缺陷的有效途径.本文提出一种基于高精度地层倾角的全体积自动拉平方法,该方法将一种自适应加权的向量滤波法获得高精度的局部地层倾角作为观测数据,根据拉平变换对每个数据样点产生的垂向偏移量与地层倾角之间的近似线性关系,建立最小二乘反演机制.在优化反演模型时,引入由梯度结构张量法得到的误差控制模板,抑制断层等复杂地质构造对拉平效果的影响;此外,增加模型参数的平滑度量项,避免拉平后的数据出现较大的畸变,并采用模型重新参数化方法,加快反演算法的收敛速度.三维合成数据和实际地震资料的试算结果表明这种三维全体积拉平方法是有效和可行的.     

Numerical study of effect of fluke inclination on behavior of drag anchor in clay with linearly increasing shear strength under unidirectional and combined loading

Drag anchor is a widely used anchor type in offshore engineering for the mooring system. The prediction of the anchor trajectory installation and the final position is important for anchor selection in design. The existing method using yield envelope method for trajectory prediction ignored the shallow anchor behavior but applied the deep yield envelope from a deeply embedded horizontal fluke in uniform clay for the whole drag-in installation process. However, the anchor fluke embedment depth and inclination angle change continually during installation in clay with linearly increasing shear strength soil profile in practice. Studies on the effect of fluke inclination angle on the anchor behavior in clay with such non-uniform soil profile under unidirectional and combined loading are important and necessary for the improvement of the yield envelope method to ensure a reasonable prediction. The current 2D finite element studies investigate the anchor behavior for inclined fluke in clay with linearly increasing shear strength under unidirectional vertical, horizontal and rotational loadings first. Then the effects of the fluke inclination angle, soil non-homogeneity and embedment depth ratio on the shallow yield envelopes are investigated. It is found that the effect of fluke inclination angle on the vertical capacity factors for anchor in clay with non-uniform and uniform soil profile is largely different. The resultant large impact on the yield envelopes shown here illustrates the importance of considering the fluke inclination angle and soil non-homogeneity in the prediction of anchor trajectory using yield envelope method.