基于图模犁和拓扑约束的管网数据一致性检测

正确可靠的数据是GIS系统的核心。针对管网数据的复杂性，提出利用圈数据模型描述管网拓扑关系．并使用拓扑约束方法对管网数据一致性进行检测，以确保数据的正确性。该方法吸收了基于连接规则以及基于拓扑关系约束的方法的优点，能够更好的描述管网系统的整体结构并对其进行拓扑约束，使得一致性检测更加全面。     

Brief Review of Some CLIVAR-Related Studies in China

The Climate Variability and Predictability （CLIVAR） program is one of the sub-programs of the World Climate Research Program （WCRP）. In this paper, CLIVAR related research in China （2003-2006） is briefly reviewed, including four major components, namely, low-frequency intraseasonal oscillations, interannual variability, decadal variations in East Asia, and global warming simulations.     

GIS中要素表达的若干问题分析及处理

以传统地图中要素表达要求为依据,分析了GIS中要素表达所存在的问题与产生的原因及其表现形式,提出了通过图层顺序控制、程序算法、符号分层绘制等多种方法来解决问题,提高了GIS可视化质量。     

基于PowerDesigner 的空间数据库建库技术

介绍了PowerDesigner的空间数据库设计方法,在建库过程中生成了概念模型和物理模型等,实现了Oracle空间数据库的建立.     

东亚夏季风强弱年大气环流和热源异常对比分析

根据黄刚等定义的东亚夏季风指数, 对强、弱东亚夏季风年大气环流、大气热源和外强迫源SST的差异进行分析, 结果表明:强 (弱) 东亚夏季风年前期冬季到夏季, 太平洋SSTA为La Ni?a (El Ni?o) 型分布, 西太平洋暖池SST暖 (冷), 使得暖池附近对流活动较强 (较弱)。与此同时, 南亚大陆从印度半岛、青藏高原南部、中南半岛至华南大气异常加热 (变冷), 并且海陆热力对比加强 (减弱), 有利于出现强 (弱) 的东亚夏季风。此外, 由于暖池附近对流活动强 (弱), 该地区上升气流较强 (弱), Walker环流增强 (减弱), 当强 (弱) 的东亚夏季风向北推进时, 副热带西风急流北撤位置偏北 (南), 副热带高压位置也偏北 (南), 7月至8月华北 (江淮流域) 位于副热带西风急流南侧, 降水偏多, 江淮流域 (华北) 降水偏少。并给出与东亚夏季风年际变异有关的大气环流和SST异常的物理图像。     

夏季东亚西风急流扰动异常与副热带高压关系研究

利用1979—2003年NCEP/NCAR月平均再分析资料, 探讨夏季 (6—8月) 200 hPa东亚西风急流扰动异常与南亚高压和西太平洋副热带高压的关系。研究指出:夏季200 hPa东亚西风急流扰动动能加强 (减弱), 东亚西风急流位置偏南 (偏北)、强度偏强 (偏弱); 东亚西风急流扰动动能强弱不仅与北半球西风急流强弱和沿急流的定常扰动有关, 而且还与东亚地区高、中、低纬南北向的扰动波列有关, 亚洲地区是北半球中纬度环球带状波列异常最大的区域。夏季200 hPa东亚西风急流扰动动能加强 (减弱), 南亚高压的特征为位置偏东 (偏西)、强度加强 (减弱); 西太平洋副热带高压的特征为位置偏南 (偏北)。东亚环流特别是500 hPa西太平洋副热带高压对东亚西风带扰动异常的响应由高空东亚西风急流南侧的散度场及其对流层中下层热带和副热带地区的垂直速度距平场变化完成。     

Connections Between Different Types of El Ni~no and Southern/Northern Oscillation

It has long been acknowledged that there are two types of El Ni(n)o events,i.e.,the eastern Pacific El Ni(n)o (EE) and the central Pacific El Ni(n)o (CE),according to the initial position of the anomalous warm water and its propagation direction.In this paper,the oceanic and atmospheric evolutions and the possible mechanisms of the two types of El Ni(n)o events were examined.It is found that all the El Ni(n)o events,CE or EE,could be attributed to the joint impacts of the eastward advection of warm water from the western Pacific warm pool (WPWP) and the local warming in the equatorial eastern Pacific.Before the occurrence of CE events,WPWP had long been in a state of being anomalous warm,so the strength of eastward advection of warm water was much stronger than that of EE,which played a major role in the formation of CE.While for the EE events,most contribution came from the local warming of the equatorial eastern Pacific.It is further identified that the immediate cause leading to the difference of the two types of El Ni(n)o events was the asynchronous variations of the Southern Oscillation (SO) and the Northern Oscillation (NO) as defined by Chen in 1984.When the transition from the positive phase of the NO (NO+) to NO- was prior to that from SO+ to SO-,there would be eastward propagation of westerly anomalies from the tropical western Pacific induced by NO and hence the growth of warm sea surface temperature anomalies in WPWP and its eastward propagation.This was followed by lagged SO-induced weakening of southeast trade winds and local warming in the equatorial eastern Pacific.These were conducive to the occurrence of the CE.On the contrary,the transition from SO+ to SO- leading the transition of NO would favor the occurrence of EE type events.     

Formation and evolution of the modem warm current system in the East China Sea and the Yellow Sea since the last deglaciation

To reconstruct the formation and evolution process of the warm current system within the East China Sea (ECS) and the Yellow Sea (YS) since the last deglaciation, the paleoceangraphic records in core DGKS9603, core CSH1 and core YSDPI02, which were retrieved from the mainstream of the Kuroshio Current (KC), the edge of the modem Tsushima Warm Current (TWC) and muddy region under cold waters accreted with the Yellow Sea Warm Current (YSWC) respectively, were synthetically analyzed. The results indicate that the formation and evolution of the modem warm current system in the ECS and the YS has been accompanied by the development of the KC and impulse rising of the sea level since the last deglaciation. The influence of the KC on the Okinawa Trough had enhanced since 16 cal kyr BE and synchronously the modem TWC began to develop with the rising of sea level and finally formed at about 8.5 cal kyr BP. The KC had experienced two weakening process during the Heinrich event 1 and the Younger Drays event from 16 to 8.5 cal kyr BP. The period of 7-6 cal kyr BP was the strongest stage of the KC and the TWC since the last deglaciation. The YSWC has appeared at about 6.4 cal kyr BP. Thus,the warm current system of the ECS and the YS has ultimately formed. The weakness of the KC,indicated by the occurrence of Pulleniatina minimum event (PME) during the period from 5.3 to 2.8 cal kyr BE caused the main stream of the TWC to shift eastward to the Pacific Ocean around about 3 cal kyr BP. The process resulted in the intruding of continent shelf cold water mass with rich nutrients. Synchronously, the strength of the YSWC was relatively weak and the related cold water body was active at the early-mid stage of its appearance against the PME background, which resulted in the quick formation of muddy deposit system in the southeastern YS. The strength of the warm current system in the ECS and the YS has enhanced evidently, and approached to the modern condition gradually since 3 cal kyr BP.     

城市创伤中心空间选址的层次分析模型

针对城市创伤中心空间选址问题,建立包含四大类、八小类影响因素的层次分析模型,邀请不同领域的专家对构造出的判断矩阵综合打分,得出各因素的相应权重后运用到深圳市创伤中心空间选址的实例研究上。模型中所涉及的空间数据均基于网络分析,更贴合实际情况。同时,考虑到深圳市创伤中心的依托医院相对集中这一特殊情况,通过聚类分析划分区域后再使用层次分析模型选址。优化后的结果将改善深圳市创伤医疗救治资源配置、提高创伤救治效率,为创伤救治机构规划部门提供参考意见。     

夏季长江淮河流域异常降水事件环流差异及机理研究

长江、淮河同处东亚中纬度,天气过程的大尺度环流背景相似,大量相关研究基本是把江淮流域天气气候事件作为一个整体研究,然而对长江、淮河流域夏季降水的时空变化进行分析发现,长江、淮河流域夏季异常降水事件有各自不同的年际、年代际变化特征,但环流差异及成因并不十分清楚。本文根据中国台站降水资料及NCEP/NCAR再分析资料,利用物理量诊断和现代统计学等方法,重点分析长江、淮河流域梅雨期降水异常事件发生时南北半球大气环流内部动力过程的差异及成因。研究指出:长江（淮河）流域梅雨期降水异常偏多年500 hPa位势高度场亚洲中高纬度环流呈现为南北向（东西向）的波列与东亚中高纬鄂霍茨克海阻塞频次增多（减少）以及200 hPa高度场上东亚副热带高空西风急流强度加强（减弱）、稳定（移动）有关;长江（淮河）流域梅雨期降水异常偏多年主要水汽来源与南半球澳大利亚高压、马斯克林高压位置偏东（西）造成西太平洋150°E～180°（阿拉伯海50°E～60°E）地区越赤道气流加强有关。长江（淮河）流域梅雨期异常降水事件大气环流内部动力过程最显著的差异表现为:东亚副热带高空西风急流加强（减弱）以及南半球澳大利亚高压、马斯克林高压位置偏东（西）。