封闭系统中多孔介质甲烷水合物的CT实验研究

阐述了在封闭系统中的查理模型,建立了利用查理定律计算分析甲烷水合物生成和分解的方法。通过实验,对封闭系统中不同含水量多孔介质甲烷水合物生成、发育和分解的实验方法、相平衡条件、生成量关系等进行了探讨。在一定温度差的介质里,水分克服重力向冷端迁移并生成水合物。实验中利用查理数的改变计算水合物的生成量变化,连通性好的含水多孔介质有很好的水—气结合条件,达到平衡条件后迅速生成水合物,在240分钟内完成,含水量线性地影响甲烷水合物的生成量。同时,利用CT扫描方法直接观测含水粗砂在低温—高压环境下的甲烷水合物生成和分解过程,并可以利用CT图像数据计算出多孔介质中水分迁移、区域密度改变和砂体的移动、及分解后介质密度分布变化特征。     

基于ArcObjects的海南省防洪应急指挥系统设计与实现

针对海南省台风、洪水灾害频繁的特点,论述了海南省防洪应急指挥系统的总体设计、系统结构设计和主要功能模块设计等内容。该系统已在实际中得到了应用。     

RFID技术在数字城市建设中的应用

介绍了RFID的基本概念和特点,并对RFID技术进行详细地阐述,探讨了RFID技术在数字城市建设中的应用。     

影像超分辨率重建技术在遥感中的应用

影像超分辨率重建是通过对多幅具有互补信息的低分辨率影像的处理,重建一幅高分辨率影像的技术,其在视频监控、医学诊断、遥感监测等领域具有很大的应用价值。以SPOT5和ADS40为例阐述了超分辨率重建技术在遥感观测系统中的应用现状,并给出了一种应用于多时相遥感影像处理的超分辨率重建方法。     

基于GIS的城市交通管理信息服务研究

论述了基于GIS技术的城市交通管理信息服务平台的总体框架和功能,并对系统集成中的关键技术进行了研究,将城市交通管理涉及的视频监控系统、电子警察系统、110/122接处警系统、路口控制系统、GPS系统、交通诱导系统等多个子系统进行整合,实现资源共享,提高系统运行效率。     

新旧国家标准地理信息分类体系的对比分析

从分类体系和语义一致性两个方面,利用定性和定量分析的方法,对比分析了新旧国家标准地理信息分类体系之间的差异,指出了新标准存在的主要问题,并提出了一些可行性的修改意见。     

矿山滑坡天线阵列变形监测系统的方案与测试

首先阐明地质灾害监测的重要性和必要性,然后分析了目前应用于滑坡安全监测自动化远程监测设备和技术,并重点介绍了GPS天线阵列变形监测系统,接着根据某矿山的一个滑坡现场,进行GPS天线阵列监测方案设计,并在实地进行数据采集测试,最后对采集数据进行处理,对几期结果的较差和精度进行分析,得出在矿山自动化监测技术中,GPS天线阵列变形监测系统是一种性价比很高的监测技术,很适合滑坡安全监测。     

Impact of 4DVAR assimilation of rainfall data on the simulation of mesoscale precipitation systems in a mei-yu heavy rainfall event

The multi-scale weather systems associated with a mei-yu front and the corresponding heavy precipitation during a particular heavy rainfall event that occurred on 4 5 July 2003 in east China were successfully simulated through rainfall assimilation using the PSU/NCAR non-hydrostatic, mesoscale, numerical model （MM5） and its four-dimensional, variational, data assimilation （4DVAR） system. For this case, the improvement of the process via the 4DVAR rainfall assimilation into the simulation of mesoscale precipitation systems is investigated. With the rainfall assimilation, the convection is triggered at the right location and time, and the evolution and spatial distribution of the mesoscale convective systems （MCSs） are also more correctly simulated. Through the interactions between MCSs and the weather systems at different scales, including the low-level jet and mei-yu front, the simulation of the entire mei-yu weather system is significantly improved, both during the data assimilation window and the subsequent 12-h period. The results suggest that the rainfall assimilation first provides positive impact at the convective scale and the influences are then propagated upscale to the meso- and sub-synoptic scales.
Through a set of sensitive experiments designed to evaluate the impact of different initial variables on the simulation of mei-yu heavy rainfall, it was found that the moisture field and meridional wind had the strongest effect during the convection initialization stage, however, after the convection was fully triggered, all of the variables at the initial condition seemed to have comparable importance.     

Characteristics and variations of the East Asian monsoon system and its impacts on climate disasters in China

Recent advances in studies of the structural characteristics and temporal-spatial variations of the East Asian monsoon （EAM） system and the impact of this system on severe climate disasters in China are reviewed. Previous studies have improved our understanding of the basic characteristics of horizontal and vertical structures and the annual cycle of the EAM system and the water vapor transports in the EAM region. Many studies have shown that the EAM system is a relatively independent subsystem of the Asian- Australian monsoon system, and that there exists an obvious quasi-biennial oscillation with a meridional tripole pattern distribution in the interannual variations of the EAM system. Further analyses of the basic physical processes, both internal and external, that influence the variability of the EAM system indicate that the EAM system may be viewed as an atmosphere-ocean-land coupled system, referred to the EAM climate system in this paper. Further, the paper discusses how the interaction and relationships among various components of this system can be described through the East Asia Pacific （EAP） teleconnection pattern and the teleconnection pattern of meridional upper-tropospheric wind anomalies along the westerly jet over East Asia. Such reasoning suggests that the occurrence of severe floods in the Yangtze and Hualhe River valleys and prolonged droughts in North China are linked, respectively~ to the background interannual and interdecadal variability of the EAM climate system. Besides, outstanding scientific issues related to the EAM system and its impact on climate disasters in China are also discussed.     

城市化进程中平原河网地区河流结构特征及其分类方法探讨

平原河网地区河流结构发育受到自然条件和城市化的双重影响。依据遥感解译数据,围绕城市化水平、河流形态、河流结构和河流调蓄功能四个维度,就建成区面积比例、河流长宽分布、河系分维、河流调蓄能力等具体指标,分析了城市化水平和土地利用特征不同区域的河流空间形态、结构特征和功能状态,探讨了城市化进程中平原河网地区河流结构的可能演化轨迹,尝试建立了城市化影响下平原河网地区河流结构分类方法,提出了城市河流综合整治过程中应充分重视保护自然河流结构,注重发挥河流综合功能等观点。