太阳射电望远镜远程控制系统

本文简要介绍了云南天文台１０ 米口径的太阳射电望远镜天线的远程控制系统中局域网控制和通过电话线控制的实现方案     

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泰安市历史形成责任灭失非煤矿山采空区现状及稳定性评价

泰安市有很多历史形成、责任灭失的铁矿、石膏矿、金矿、长石矿、萤石矿、岩盐矿等非煤矿山。该文阐述了各矿山的采空区位置、分布范围、危险性及废弃矿井的位置、类型,分析了地表变形及其对建(构)筑物及基础设施的潜在影响,采用赋值打分法和规范评价法对采空区稳定性进行评价,对废弃矿井危害程度进行定性分析评价。在调查与评价的基础上,对泰安市历史形成、责任灭失非煤矿山采空区及废弃矿井提出针对性的防治措施,为开展防治工作提供参考和依据。     

Initial results of centralized autonomous orbit determination of the new-generation BDS satellites with inter-satellite link measurements

Autonomous orbit determination is the ability of navigation satellites to estimate the orbit parameters on-board using inter-satellite link (ISL) measurements. This study mainly focuses on data processing of the ISL measurements as a new measurement type and its application on the centralized autonomous orbit determination of the new-generation Beidou navigation satellite system satellites for the first time. The ISL measurements are dual one-way measurements that follow a time division multiple access (TDMA) structure. The ranging error of the ISL measurements is less than 0.25 ns. This paper proposes a derivation approach to the satellite clock offsets and the geometric distances from TDMA dual one-way measurements without a loss of accuracy. The derived clock offsets are used for time synchronization, and the derived geometry distances are used for autonomous orbit determination. The clock offsets from the ISL measurements are consistent with the L-band two-way satellite, and time–frequency transfer clock measurements and the detrended residuals vary within 0.5 ns. The centralized autonomous orbit determination is conducted in a batch mode on a ground-capable server for the feasibility study. Constant hardware delays are present in the geometric distances and become the largest source of error in the autonomous orbit determination. Therefore, the hardware delays are estimated simultaneously with the satellite orbits. To avoid uncertainties in the constellation orientation, a ground anchor station that “observes” the satellites with on-board ISL payloads is introduced into the orbit determination. The root-mean-square values of orbit determination residuals are within 10.0 cm, and the standard deviation of the estimated ISL hardware delays is within 0.2 ns. The accuracy of the autonomous orbits is evaluated by analysis of overlap comparison and the satellite laser ranging (SLR) residuals and is compared with the accuracy of the L-band orbits. The results indicate that the radial overlap differences between the autonomous orbits are less than 15.0 cm for the inclined geosynchronous orbit (IGSO) satellites and less than 10.0 cm for the MEO satellites. The SLR residuals are approximately 15.0 cm for the IGSO satellites and approximately 10.0 cm for the MEO satellites, representing an improvement over the L-band orbits.     

顾及GRACE季节影响的华北平原水储量变化反演

基于移去-恢复方法,利用GRACE卫星重力数据研究了华北平原2003年1月—2014年6月的陆地水变化,提出了一种顾及季节影响尺度因子计算方法,用于减小GRACE后处理误差。将本文方法所得结果与水文模式和降水模型结合进行比较分析,结果表明：2008年之前华北平原发生比较明显的干旱现象,陆地水和地表水分别以（-7.9±2.4）mm/a和（-7.3±2.8）mm/a的速度下降,但地下水仅以（-0.6±1.4）mm/a的速度减少;2008年之后,陆地水和地表水分别以（4.3±1.3）mm/a和（10.9±2.1）mm/a的速度上升,期间地下水的超采严重,平均以（-6.5±1.2）mm/a的速度下降,但下降速度以0.9 mm/a²的趋势减缓。研究期间内,华北平原的陆地水、地表水和地下水整体分别呈现（-2.0±0.6）、（2.9±0.7）和（-4.8±0.7）mm/a的变化趋势。最后,利用交叉小波谱分析了GRACE滞后于降水的现象。研究结论表明,降水和地下水开采是影响华北平原水储量变化的两大决定性因素。     

高分辨率遥感卫星颤振探测的相位相关分析法

平台颤振是影响高分辨率卫星影像几何和辐射质量的关键因素。为提高从影像反演平台颤振特性的可行性和可信度,本文提出基于局部频率分析相位相关的智能化视差法颤振探测方法。通过结合结构影像表达和相位相关,并充分利用影像的局部和全局相位信息,减少了辐射变化和噪声等干扰因素对亚像素偏移值估计的影响,同时融入视差法颤振探测框架,保证精确稳健的密集匹配,从而实现高效的平台颤振精密探测。通过采用实际辐射变化数据集的算法对比及采用资源三号卫星影像的颤振探测试验验证了本文方法的有效性。结果表明,局部频率分析相位相关算法在辐射差异和噪声等情况下效果优于其他主流相位相关算法,匹配精度达到0.05个像素,本文颤振探测方法有效估计了资源三号卫星的颤振信息。     

资源三号卫星在区域地质灾害应急监测中的应用——以山西省为例

遥感技术已成为当前应对突发地质灾害应急监测的一种重要技术手段。本文将资源三号卫星遥感影像应用于区域地质灾害应急监测中,研究了资源三号卫星区域RPC参数的修正方法,并联合DEM和控制点建立了区域影像快速正射纠正的方法流程;利用长治地区的资源三号卫星影像进行了正射纠正试验与分析,总体满足区域地质灾害应急监测对遥感影像的精度要求。利用该方法制作完成的地质灾害区域遥感影像已应用于山西省突发地质灾害遥感监测指挥系统项目中并取得了较好的应用效果。     

UAV航测和TLS技术在广钢遗址测绘建模中的应用

联合应用地面三维激光扫描技术和无人机航测技术采集了广钢炼钢遗址空间数据,并进行了现状测绘与三维建模。三维激光扫描获取遗址内外高精度点云数据;无人机航测获取遗址顶部点云及周边地形DSM和DOM,将航摄DSM数据拟合到激光点云上,使得航摄DSM精度达到12.6cm,且弥补了激光点云的漏洞;采用融合的点云数据测制了平立剖测绘图,建立了三维模型。上述两种技术优势互补,形成了一种高效率、高精度、全方位的历史遗迹测量与建模的解决方案。     

情境建模下的LBS智能信息服务推送方法

为满足移动互联网用户的个性化信息服务需求,引入用户兴趣模型匹配技术,提出了一种基于情境建模下的LBS智能信息推送服务模式,通过构建位置过滤模块、用户兴趣模型匹配及智能信息分类模块,实现了对推送信息的层层过滤,并同时结合反馈处理部分的修正功能实时改进推送模型的精度,从而提高了信息服务的质量和效率,使推荐的信息资源更加符合用户的实际需要。原型系统的实际应用表明了该方法的有效性。