AutoCAD与其他常用软件的数据转换

本文就AutoCAD与生产应用中常用的ARCGIS、ARC／INFO、MicroStation、3DS等软件系统之间的数据转换作一些浅谈。     

基于J2EE的移动定位服务研究

阐述了基于J2EE的移动定位服务 (MLS)的体系结构 ,介绍了适于MLS的GIS应用服务器和信息设备地图可视化表达的关键技术 ,给出了GeoSurf的WAP和J2ME的两种解决方案 ,并阐述了其应用前景     

海量地形数据的Web发布与交互浏览

阐述了基于CORBA的分布式平台实现异构网络环境下海量地形数据的Web发布与服务的关键技术 ,通过一个实验系统对上述方法进行了测试     

Estimation of ocean primary productivity and its spatio-temporal variation mechanism for East China Sea based on VGPM model

According to calculation results of ocean chlorophyll concentration based on SeaWiFS data by SeaBAM model and synchronous ship-measured data, this research set up an improved model for CaseⅠand CaseⅡwater bodies respectively. The monthly chlorophyll distribution in the East China Sea in 1998 was obtained from this improved model on calculation results of SeaBAM. The euphotic depth distribution in 1998 in the East China Sea is calculated by using remote sensing data of K490 from SeaWiFS according to the relation between the euphotic depth and the oceanic diffuse attenuation coefficient. With data of ocean chlorophyll concentration, euphotic depth, ocean surface photosynthetic available radiation (PAR), daily photoperiod and optimal rate of daily carbon fixation within a water column, the monthly and annual primary productivity spatio-temporal distributions in the East China Sea in 1998 were obtained based on VGPM model. Based on analysis of those distributions, the conclusion can be drawn that there is a clear bimodality character of primary productivity in the monthly distribution in the East China Sea. In detail, the monthly distribution of primary productivity stays the lowest level in winter and rises rapidly to the peak in spring. It gets down a little in summer, and gets up a little in autumn. The daily average of primary productivity in the whole East China Sea is 560.03 mg/m2/d, which is far higher than the average of subtropical ocean areas. The annual average of primary productivity is 236.95 g/m2/a. The research on the seasonal variety mechanism of primary productivity shows that several factors that affect the spatio-temporal distribution may include the chlorophyll concentration distribution, temperature condition, the Yangtze River diluted water variety, the euphotic depth, ocean current variety, etc. But the main influencing factors may be different in each local sea area.     

宁夏气象影视数字化节目制作系统的建立

在信息传播媒体的竞争日益严酷的时代,面对天气预报节目只依靠简单的画面加解说,拉洋片式传统方法这样一种一成不变的局面,策划创意制作出《天气资讯》节目,打破天气预报节目以往的节目形式和播出形式,以极少的投入获得最大的社会效益和经济效益。     

应用多传感器目标跟踪融合技术实现滑坡多点监测数据综合信息的提取

目前的滑坡预报模型只能利用一个关键监测点的监测数据，而不能同时利用多个监测点的监测信息，即只能处理一维时间序列问题.为了解决这个技术难题，本文将滑坡视为一个机动目标，将对滑坡的监测视为对机动目标的跟踪，提出了利用多传感器目标跟踪融合技术来处理滑坡多个点的监测数据的方法，分析了其可行性，并用实例说明了本文提出的方法在实际应用中是有效的.     

论城市应急避险场所建设

做好减灾工作,加强应急避险场所建设是一项重要的任务,是落实以人为本,构建和谐社会的具体体现之一。1城市应急避险场所的性质笔者认为,城市避险场所的定义为:城市应急避险场所是为城市或城镇受到各种灾害侵袭而暂时离开居所的人群临时提供的、利用各种空旷场地和大型馆所预先设立的躲避灾难、居留和生活的公共场所。各种灾害包括自然灾害、事故灾难、突发公共卫生灾害、突发社会安全事件等。受助人群包括当地居民以及受灾当地的外来人群。避险场所提供的是临时性的居留场所,其基本服务是政府免费提供的,一旦灾难结束或受灾家园得到重建,停…     

Real-time simulation of ground displacement by digital accelerograph record

Introduction The observation records of strong ground motion previously, on the one hand, supplied basicdata both to research on earthquake engineering and to constitute the criterion of aseismatic de-signing of all project structures; on the other hand, it provided important information for the re-search on the process of epicenter burst in seismology. With the development of research on strongground motion observation, especially the development of the new generation accelerograph,which…     

Study on comparison between absolute and relative input energy spectra and effects of ductility factor

Introduction Estimation of an attenuation relationship for strong ground motion parameters has been an interesting research subject in the field of engineering seismology and has played a very important role in seismic safety evaluation, seismic zoning, seismic hazard evaluation of major constructions, etc. At present, the generally used parameters include peak acceleration, peak velocity and elastic response spectrum. Such parameters mentioned above are essentially independent of the duration…     

Multifield coupling model and its applications for pile foundation in permafrost

In the construction of Qinghai-Tibet railway,to avoid diseases caused by frost heave and thaw col-lapse of frozen ground,besides the normal bridges over the rivers,a lot of dry bridge structures have been built to replace subgrade in the regions of high tem-perature and high ice content frozen soil.So,the problems on forming mechanism of bearing capacity of pile foundation in cold regions already become one of hot spot problems in frozen soil engineering.Freezing force and frost heave force ar…