台风森拉克移动路径分析

台风路径的预报是做好台风预报服务的关键.利用Micaps系统提供的资料,分析中高纬度波动对副热带高压的影响,台风外围弱气旋性环流的移动、变化,综合分析物理量场的分布、变化以及相关的数值预报产品可以较准确预报台风移动路径.     

0312台风"科罗旺"路径及其暴雨成因分析

0312台风"科罗旺"是2003年在我国登陆最强的一个台风,给海南、广东、广西3省带来巨大损失,本文利用常规资料和卫星等资料,对其路径及其暴雨成因综合分析,结果表明:势力强盛的西太平洋副高经历一次短周期活动,是台风先向西南西移动,后转向西北西的主要成因;低层台风中心附近涡度长轴方向预示其未来的移向;对流云团的不断旋入台风环流,低层水汽辐合、高层辐散和强烈的上升运动导致3省暴雨灾害.     

台风森拉克路径特征与预报难点分析

研究了2002年16号台风路径的分析与预报过程,分析了0216号台风在几次关键点的预报过程中出现疑难,预报争议很大的原因.认为类似0216号台风,在其生命史中遇到环境场气压系统比较弱时,要注意可能出现路径停滞、打转、转折等.这时,应仔细分析,避免对预报思路的误导,减少预报服务思路的大幅度摆动,以提高服务质量与效果.注意台风周围的涡旋发生互旋的半径变化、影响的程度,在分析弱涡旋时,注意水汽通道云图等其他参考工具是有意义的.     

登陆海南岛台风季节特征的对比分析

通过对2003年盛夏(8月份)和晚秋(11月份)登陆海南岛的两个台风个例进行了大尺度环流背景、台风暴雨产生的大尺度条件、中尺度特征等方面的对比分析，揭示盛夏和晚秋登陆海南岛台风路径和暴雨的一般特性’并对其成因进行了探讨。     

Variations of δ^18 O in Precipitation along Vapor Transport Paths

Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ^18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ^18 O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the 51so in the rainy season smaller than inthe dry season. The δ^18 O sovalues in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ^18 O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ^18 O in precipitation reaches its minimum at Uriimqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ^18 O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ^18 O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ^18 O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season,but δ^18 O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ^18 O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ^18 O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.     

阿克苏地区强冰雹云移动路径分析

利用阿克苏地区1996～2003年的冰雹落区覆盖面积达667hm2以上的个例的雷达资料,进行统计分析,得出强冰雹天气背景下的天气系统类型、冰雹路径,并提出相应的防御对策.     

台风云娜路径和强度特点分析

通过对大尺度环流背景、副高强弱变化、温度场的分布以及高低空急流的研究表明:影响0414号台风云娜路径多变的主要因素是西风带环流调整和副高增强过程中相互作用所致;而台风登陆后强度减弱慢、持续时间长是由于低空存在水汽能量输送带以及具有台风涡旋发展的高低空急流和高低空辐合辐散场配置.     

Numerical Method for Modeling the Constitutive Relationship of Sand under Different Stress Paths

Overonehundredconstitutivemodelsforsand havebeenproposed,howeveronlyafewmodelsare widelyappliedinengineering.Therearetwochief reasonsforthis.(1)Sandiscomposedofgeological materialsandsituatedinaneutralenvironmentthat hassufferedvariousactions.Therefore,itisdifficult todescribethecomplexbehaviorofsoilsbyusinga simplemathematicalmodelwithonlyafewparame ters.(2)Therealsoexistsabasicparadoxintradi tionalmodelingmethods.Oneaspectofthemodelsis neededtodescribetheconstitutiverelationofsoilac curatel…     

第21章：地震图的结构及解释

地震图的解释是用于识别地震记录上出现的且形成相当复杂结构的各种地震波（震相）的技艺。正确识别所记录的震相及该震相在地球内部的传播路径是所有利用地震观测数据进行研究的途径。一幅地震图的形态反映了震源、传播路径、仪器特性和接收台站周围噪声的共同作用。理解地震图的复杂结构需要震源物理、地球结构和地震波传播的知识。总之，需要有分析地震波的长期经验。一个经验丰富的地震图分析员经常可发现并正确解释新手们不能察觉的记录特征，     

最短路径算法用于城市公交出行路径最优化

介绍了经典Dijk st ra算法的主要思想快速实现方法，指出了公交网络不同于一般的道路网络的特点，给出了选择公交出行路径的算法思想。