多功能地质勘察平台关键结构设计与应用

本文结合小型简易式平台、“探海1号”大陆架科学钻探平台等设计建造应用的经验,对多功能地质勘察平台模块化连接、升降模块以及桩靴等关键结构进行设计及应用,创新设计解决了平台建造场地限制、运输、方便安装等问题,提高了平台升降、迁移的效率,以适应短周期、需频繁移动平台的海上工程勘察项目。通过实际应用效果良好。     

Analysis of Meteorological and Terrain Features Leading to the Izmir Flash Flood, 3–4 November 1995

Flash floods associated with heavy precipitation has become a hazardous phenomenon along the Mediterranean coasts of Turkey in recent years. During 3 and 4 November 1995 heavy and intense rainstorm activity over the Aegean coast led to flash flooding in the city of zmir. Damage exceeded $50 million and 61 people died as a result of the flood. The Karyaka district suffered the most severe damage. This study presents an analysis of the meteorological settings that led to the development of these intense storms and describes the role of the terrain features involved in the zmir flood.The important mesoscale features which initiated the severe weather outbreak included pronounced low-level advection, positive vorticity and strong upper level divergence. A surface low centered over the Aegean Sea enhanced the advection of warm and moist unstable air masses coming from the southwest over the Mediterranean Sea along a southwesterly low level jet (LLJ). A squall line oriented NE-SW over the Aegean Sea also contributed to the storm development, and intensity of the storms was further enhanced by the orographic effect. The presence of a frontal system, the stability indices associated with the event, and other meteorological features are all reminiscent of the synoptic type flash floods identified by Maddox. While the pressure and moisture patterns were favorable for severe storm activity, nonmeteorological factors including the topography, geomporphology, and and land-use contributed to the flooding to a great extent. Settling in the flood-prone zone, insufficient floodwater structures, and the lack of channel improvements in the creeks enhanced flood damage to the city. Many of the deaths occurred in the settlements located in the flood-prone zone of the Ilca and Dallk creeks.     

超大型导管架下水过程实测研究

以某超大型导管架为例,利用惯性元件/GPS组合系统分别对导管架和驳船在下水过程中的运动轨迹进行测量。当导管架处于水面上时,利用精度较高的GPS测量其运动速度;当导管架入水后,GPS失效,利用惯性元件测量导管架加速度;结合姿态矩阵解算导管架和驳船在下水过程中的运动时历;对比导管架运动的实测和数值计算的结果,验证数值计算的准确性。结果显示,采用惯性元件/GPS组合系统可以准确测量出导管架在下水过程中的运动轨迹;数值计算得出的运动幅值略大,原因可能是计算中的阻尼估计不足。     

深海扬矿泵导叶结构中粗颗粒运动特性研究

扬矿泵作为深海采矿水力提升系统中的关键设备,其设计参数对安全、高效输送矿石有着重要作用。通过对扬矿泵导叶区域中的颗粒进行受力分析,建立受力方程和运动方程,从扬矿泵结构参数和输送参数两个方面来研究颗粒在扬矿泵导叶中的运动情况。研究结果表明:1)当颗粒粒径一定的条件下,相比于25°和30°的导叶进口安放角θ,15°~20°时颗粒将在更短的时间内以更快的速度与导叶壁面发生碰撞,这样对导叶的磨损更严重,但当θ大于25°时,导叶曲面弯曲过急,不利于颗粒过泵,因此,在此研究中选择导叶进口安放角为25°较合适;2)流道宽度小于3d_(max),颗粒与导叶碰撞位置越靠近导叶进口,碰撞时颗粒的速度越大,对泵的磨损越严重,流道宽度大于3d_(max),导叶的导流效果降低,综合考虑,选择流道宽度为3 d_(max)较佳;3)当水流速度在2~5 m/s时,颗粒与导叶碰撞瞬间,水流速度大的工况下,颗粒会以更大的速度与导叶碰撞,这样对机械的磨损更严重;4)细颗粒不容易与导叶碰撞,同一流速下,粒径越大的颗粒在导叶中的停留时间越长,会增加堵泵的概率。     

基于提升型小波变换的矢量数据渐进式传输的研究

根据网络环境下矢量数据的存储及显示特点和人们由粗到细、由总体到局部的空间信息认知规律,利用小波分析的特性,对原数据采用小波变换的方法进行分层、分块处理,然后根据用户需求,按顺序进行分块传输、分块显示,提高用户的作业响应时间,同时使用户在不增加网络流量的前提下,得到多尺度的空间矢量数据。实现空间矢量数据的渐进式网络传输。     

第2代双正交小波的上升型构造及其应用

介绍了双正交小波分解的基本理论，并用数字滤波器的观点分析了双正交小波函数所满足的条件；讨论了双正交小波函数及滤波器的上升型构造方案，在此基础上从最简单的Haar小波基出发，通过上升型步骤构造出具有不同特性的第2代双正交小波数字滤波器；最后给出了基于第2代双正交小波变换的图像放大算法及实验结果。     

An Image Fusion Algorithm Based on Lifting Scheme

Taking the advantage of the lifting scheme＇s characters that can build wavelet translorms tor transforming from integer to integer and the quality of the reconstructing image＇is independent of the topology way adopted by the boundary, an image fusion algorithm based on lifting scheme is proposed. This paper discusses the fundamental theory of lifting scheme firstly and then after taking transform analysis according to a kind of images that need to be confused.     

基于全耦合模型的海上吊装作业动力响应特征研究

针对现有海上吊装模拟方法不能有效考虑浮吊船舶—系泊系统—吊物系统之间的动态耦合,难以实现基座回转、吊臂变幅连续模拟问题,基于Matlab/Simulink、ADAMS联合仿真平台建立了海上吊装作业全耦合动力分析模型,探究了中长周期波作用下波浪周期、吊缆收放、基座回转、吊臂变幅等参数变化对吊装作业系统动力响应的影响规律。结果表明,波浪周期接近吊物系统固有周期时会引发共振,导致吊物摇摆幅值显著增加。基座回转、吊臂变幅等因改变了吊物的空间位置从而引发了浮吊船舶倾覆力矩的变化,进而对浮吊船舶运动响应产生显著影响。当基座回转90°后,浮吊船舶的横倾角增加约2.74°。     

提升小波:可用于重磁资料处理的新方法

小波变换在重磁资料处理中得到了广泛应用．通过提升结构构造的二代小波继承了一代小波的优良属性,并且具有灵活性、适应性、易于快速实现等优点．二代小波比一代小波有很多优点和好的属性,其应用范围更为广泛．本文介绍了提升结构构造二代小波的思想,并讨论了其在重磁资料处理中的应用前景．     

Seismic data compression based on integer wavelet transform

Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied. Comparing with the traditional algorithm, it can better improve the compression rate. CDF (2, n) biorthogonal wavelet family can lead to better compression ratio than other CDF family, SWE and CRF, which is owe to its capability in canceling data redundancies and focusing data characteristics. CDF (2, n) family is suitable as the wavelet function of the lossless compression seismic data. Contribution No.04FE1019, Institute of Geophysics, China Earthquake Administration.