路用探地雷达的应用技术研究进展

有效、无损、快捷、简便是公路检测技术发展的方向，当前国内外先进的浅层勘探技术——路用探地雷达检测，以其无损、快捷以及浅层高分辨率的优势被迅速应用于公路检测。本文对近年来路用探地雷达技术的发展及应用情况进行了介绍，详细分析了探地雷达的工作原理、系统组成结构。就探地雷达在公路建设、维护过程中的应用情况进行了系统总结。     

利用卫星测高资料推求西北太平洋海域的海洋大地水准面

本文根据卫星测高数据和海面动力地形资料，绘制了不相上下北太平洋海域局部大地水准面的精细结构图，对解决卫星测高技术中大地水准面积和海面地形的可分性问题作了初步尝试。     

Theory of satellite ground-track crossovers

The fundamental geometry of satellite ground tracks and their crossover problem are investigated. For idealized nominal ground tracks, the geometry is governed by a few constant parameters whose variations lead to qualitative changes in the crossover solutions. On the basis that the theory to locate crossovers has not been studied in sufficient detail, such changes are described in regard to the number of crossover solutions in conjunction with their bifurcations. Employing the spinor algebra as a tool for establishing the ground-track crossing condition, numerical methodologies to locate crossovers appearing in general dual-satellite ground-track configurations are also presented. The methodologies are applied to precisely determined orbital ephemerides of the GEOSAT, ERS-1, and TOPEX/POSEIDON altimeter satellites. Received: 19 November 1996 / Accepted: 12 May 1997     

现代大地测量在研究相关地学问题中的作用

本文评述了用现代大地测量技术监测地球动力现象所能达到的时空辨率和准确度论述了大地测量在研究相关地学问题中的作用，回顾了以空间卫星大地测量为标志的现代大地测量近３０年来对地球科学作出的主要贡献及科学意义，并对大地测量未来进一步应用于地学研究的主要领域和研究方向提出了若干建议。     

电法勘探的发展和展望

电法勘探在经历了近一个世纪的发展后，其方法理论、仪器设备、野外数据采集、处理和解释等方面都经历了一系列重大变化．本文以方法理论的进展为主线，回顾、展望了目前电法勘探中几个重要而令人关注的研究焦点．这些问题的研究进展将会对21世纪的电法勘探产生深远的影响．     

巷道围岩松动圈的地质雷达探测及应用

在简述地质雷达探测原理的基础上, 分析了巷道围岩松动圈雷达探测的可行性。结合华丰矿巷道围岩松动圈探测实例, 提出了松动圈雷达探测方法、图像分析及探测结果应用。结果表明, 采用地质雷达探测巷道围岩松动圈是可行的, 可以用于指导巷道围岩的锚杆支护设计。     

南昌多普勒雷达与713-C雷达降水回波产品对比分析初探

通过对比多普勒雷达和713-C雷达在同一时间、同一站点对降水回波的探测资料,找出它们在同类产品上的差异,对完成713-C雷达观测向多普勒雷达观测的过渡,用好多普勒雷达提供参考性意见。     

2002年秋季山东省干旱遥感监测分析

利用极轨气象卫星遥感资料对2002年山东省秋季干旱进行监测和服务,其监测方法主要采用热惯量法。为了提高土壤水分模式的计算精度,将全省分为4个区域,对利用卫星资料反演的地表温度日较差进行植被指数等环境因素订正。在地理信息系统支持下,比较准确地计算出农田受旱面积,效果良好。     

泰国水稻种植面积月变化的遥感监测

介绍了光学和微波遥感影像相结合进行泰国水稻种植面积监测方法。泰国雨季雨量充足 ,气温适合 ,同一时间耕地上水稻的物候多样 ,每月水稻种植面积都发生变化。利用旱季的TM影像 ,获得耕地信息。同时利用TM影像覆盖的雷达区域进行非耕地去除 ,进行非监督分类 ,提取反映水稻种植不同生长期的雷达影像后向反射系数特征 ,建立各种类型的分类模型 ,采用监督分类的方法对全景雷达数据进行水稻种植情况调查 ,并分别予以识别和统计 ,反映研究区水稻月种植情况。分类结果通过类别检验和面积量算检验进行精度评价和分析。     

The gravity field and GGOS

The gravity field of the earth is a natural element of the Global Geodetic Observing System (GGOS). Gravity field quantities are like spatial geodetic observations of potential very high accuracy, with measurements, currently at part-per-billion (ppb) accuracy, but gravity field quantities are also unique as they can be globally represented by harmonic functions (long-wavelength geopotential model primarily from satellite gravity field missions), or based on point sampling (airborne and in situ absolute and superconducting gravimetry). From a GGOS global perspective, one of the main challenges is to ensure the consistency of the global and regional geopotential and geoid models, and the temporal changes of the gravity field at large spatial scales. The International Gravity Field Service, an umbrella “level-2” IAG service (incorporating the International Gravity Bureau, International Geoid Service, International Center for Earth Tides, International Center for Global Earth models, and other future new services for, e.g., digital terrain models), would be a natural key element contributing to GGOS. Major parts of the work of the services would, however, remain complementary to the GGOS contributions, which focus on the long-wavelength components of the geopotential and its temporal variations, the consistent procedures for regional data processing in a unified vertical datum and Terrestrial Reference Frame, and the ensuring validations of long-wavelength gravity field data products.