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金属丝网橡胶材料是一种完全由金属丝编织成的多孔复合材料,与传统螺旋卷制金属橡胶材料相比,其改进了成型工艺,剔除了制备过程中大量的手工工艺干扰,提高机械化程度,重合度更高,拥有更稳定的力学性能.由于金属丝网橡胶材料具有承载能力高、阻尼大、耐高温、耐低温、耐老化、抗油抗腐蚀等优良特性,在很多方面强于传统橡胶,多用于航空航天、船舶、军事武器等军工工业.弹簧--金属丝网橡胶组合减振器具有可设计刚度和较高承...
CHALLENGES WITH OBSTACLE DATA FOR MANNED AND UNMANNED AVIATION
Obstacle data UTM U-Space Aircraft Drones Personal air vehicles
2018/11/9
The objective of this paper is to raise awareness about the significance of collecting and ensuring the quality of the obstacle data required for the safety of air navigation for both manned and unman...
MP-WFRFT系统中8PSK星座裂变图案分析
多参加权分数阶傅里叶变换 8PSK 星座裂变 混合整数优化 抗截获
2019/1/18
为进一步探究多参加权分数阶傅里叶变换（multiple parameters weighted-type fractional Fourier transform，MP-WFRFT）对高阶基带星座的影响，对MP-WFRFT变换中的8PSK基带星座裂变规律进行了定性与定量研究。通过定义星座裂变函数，并搭建相应几何模型，采用向量合成的基本方法，推导得出基于MP-WFRFT变换的8PSK星座裂变规律。进...
基于高斯过程的飞行转弯区一致性监视技术研究
飞行轨迹 高斯分布 采样 协方差矩阵
2019/1/18
针对导航误差和监视误差等干扰因素以及飞行转弯固有的不确定性和可变性，比如转弯开始点和转弯半径的差异，造成飞行转弯区内难以判定航空器是否与飞行计划或管制指令一致的问题，提出了一种比较航空器系统状态预期值和实际测量值的一致性监视方法，该方法基于高斯过程对转弯区的一致性飞行建模，通过模型求解出预期的状态值范围，其中引入附加的偏离项使模型有效地描述了飞行转弯区各个时段内系统状态值的合理变化趋势。系统状态预...
改航是航班运行过程中应对恶劣天气、军事活动、流量管控等突发情况的重要策略。作者提出一种挖掘历史雷达数据特征的改航算法。算法首先综合考虑改航路径的经济性、安全性、航路特征和容量影响等因素建立改航约束条件，对航班可能的改航区间的航路通路进行分析初选，确定最优的改航区间及其满足改航约束条件的一系列关键点序列。随后基于航班在历史雷达数据中的位置信息分析关键点序列航段执行情况，结合该航段计划航班数据，提出了...
航班轨迹预测是空中交通管理与仿真技术的基础。针对现有预测方法预测精度和稳定性不足的问题，提出了一种基于历史雷达数据和机器学习方法的轨迹预测算法。算法首先基于概率统计模型（高斯混合模型）对航班运行过程中的相邻时刻的相对位置偏移量进行建模；随后，以该航班的历史飞行轨迹为训练数据采用期望最大化的机器学习算法优化模型参数。概率统计模型学习真实运行环境下同一航班的飞机运动模式，能更准确地描述航班在飞行过程的...
MAPPING SPATIOTEMPORAL DISTRIBUTION OF MANGROVES IN MAFIA ISLAND IN TANZANIA USING LANDSAT IMAGERY
Mapping Mangroves Satellite Image Landsat Mafia Island
2018/11/8
Mangroves are important for survival of coastal communities as they provide ecosystem services that support coastal population and their livelihoods. Most coastal communities largely depend on ecosyst...
一种卫星推进分系统热控的优化设计方法
卫星推进分系统 热控 优化设计 分舱操作
2018/5/4
根据传统卫星推进分系统热控要求，针对推进舱内肼管路及部件进行加热带缠绕和多层隔热组件包覆的问题，提出了一种基于新型推进剂条件下的推进分系统热控优化设计，即取消推进舱内热控处理措施，而是在推进舱的外侧板包覆多层隔热组件，并采用电磁阀补偿加热.对采用优化设计的推进分系统热控设计进行了热平衡试验和在轨验证.结果表明，推进分系统的温度水平和功耗要求均满足目前中国对于卫星的热控要求，且优化设计使推进分系统热...
IMAGE QUALITY ASSESSMENT OF HIGH-RESOLUTION SATELLITE IMAGES WITH MTF-BASED FUZZY COMPREHENSIVE EVALUATION METHOD
Image Quality Assessment High-resolution Satellite Images MTF Fuzzy Comprehensive Evaluation
2018/5/15
A Modulation Transfer Function (MTF)-based fuzzy comprehensive evaluation method was proposed in this paper for the purpose of evaluating high-resolution satellite image quality. To establish the fact...
MAPPING GLOBAL OCEAN SURFACE ALBEDO FROM SATELLITE OBSERVATIONS: MODELS, ALGORITHMS, AND DATASETS
Albedo Ocean BRDF Remote sensing Radiative transfer Surface radiation budget
2018/5/14
Ocean surface albedo (OSA) is one of the important parameters in surface radiation budget (SRB). It is usually considered as a controlling factor of the heat exchange among the atmosphere and ocean. T...
AN INTERFEROMETRIC PROCESSING METHOD TO MAINTAIN BOTH ACCURACY AND RESOLUTION OF DEM USING GAOFEN-3 SAR DATA
Gaofen-3, TanDEM-X, DEM, multi-look
2018/5/14
Gaofen-3 (GF-3) is the only in-orbit SAR satellite of China civilian fields. It is designed especially for ocean observation but not for interferometric applications. However, during the past one and ...
DISCUSSION ON HEIGHT SYSTEMS IN STEREOSCOPIC MAPPING USING THE ZY-3 SATELLITE IMAGES
ZY-3 Stereoscopic Satellite Mapping Geoid Ellipsoidal height Orthometric height Accuracy
2018/5/16
The ZY-3 is the civil high-resolution optical stereoscopic mapping satellite independently developed by China. It is mainly used for 1 : 50,000 scale topographic mapping. One of the distin...
COMPARISON AND ANALYSIS OF ACCURACY OF ELEVATION EXTRACTION BASED ON THE ZY-3 01 AND 02 SATELLITES STEREOSCOPIC IMAGES
ZY-3 Stereoscopic Satellite GSD DEM differential DEM, Accuracy
2018/5/16
The ZY-3 is the civil high-resolution optical stereoscopic mapping satellite independently developed by China. The ZY-3 constellation of the twin satellites operates in a sun-synchronous, near-polar, ...
AN IMPROVED DEM CONSTRUCTION METHOD FOR MUDFLATS BASED ON BJ-1 SMALL SATELLITE IMAGES: A CASE STUDY ON BOHAI BAY
Mudflats BJ-1 image Waterline detection method Tidal grid model DEM
2018/5/15
The topographic measurement of muddy tidal flat is restricted by the difficulty of access to the complex, wide-range and dynamic tidal conditions. Then the waterline detection method (WDM) has the pot...
COMPARISON OF THE LINEAR AND THE NON-LINEAR BLOCK ADJUSTMENT ON SATELLITE IMAGES RESEARCH
Linear Least square method Non-Linear Least square method error equation Block adjustment Rational Function Model High-resolution Satellite images
2018/5/14
The Rational Function Model （RFM） is a non-linear model. Usually, the RFM-based satellite image block adjustment uses the Taylor series to expand error equations, and then solves the linear model. The...