遥感应急目标影像自动检测及制图方法

针对点目标检测的应急响应,提出一种适用于该类场景的通用应急目标影像自动检测及制图方法,能实现主目标提取与轮廓分析相结合,从而快速提取应急目标。通过改进的分水岭分割算法提取主目标信息,对分割结果进行轮廓结构分析,形成应急响应专题图。在突发事件产生水坑的应急实例中,选取高分二号卫星影像数据,在汶川山体滑坡应急实例中,选取高分一号卫星影像数据,均获得了良好的提取效果。其中,应急水坑检测的误差率是1. 2%,山体滑坡检测的误差率是1. 7%,表明文章提出的方法能很好地满足应急响应中点目标检测的需求。     

高分遥感影像林地资源信息提取方法研究

林地资源是森林资源的重要组成部分,在空气净化、自然防疫、制氧、气候调节等方面均具有重要作用。本文应用GF-1卫星数据,基于e Cognition软件平台,采用面向对象方法对廊坊市永清县2013年11月GF-1影像进行林地信息提取。通过多尺度分割试验确定最优尺度分割参数,结合影像地物纹理、光谱特征,采用模糊逻辑分类算法实现林地信息高效提取。     

基于U-net的"高分五号"卫星高光谱图像土地类型分类

"高分五号"卫星是世界首颗实现对大气和陆地综合观测的全谱段高光谱卫星,对于土地利用类型分类具有重要的应用价值,如何利用深度学习技术开展高光谱图像分类是当前研究的热点问题。深度学习中的语义分割方法在地面场景的图像中已经获得较好的应用,但是对于高光谱遥感图像的精度和适用性较差,无法准确获得精确的分类结果。文章采用U-net模型开展高光谱土地利用类型分类研究,首先基于"高分五号"卫星高光谱数据,构建样本数据集,然后训练分类模型,进行土地利用类型分类,探讨语义分割方法在高分五号高光谱数据上的应用能力。结果表明,采用深度学习中的语义分割方法能够有效提高精度水平,U-net模型的整体分类精度为0.9357,Kappa系数达到0.92,均高于SVM方法和CNN方法。采用深度学习中的语义分割方法,可以为"高分五号"高光谱数据的土地利用分类提供技术支撑,有效提升"高分五号"卫星的应用能力。     

一种面向对象的机场跑道变化检测方法

利用遥感影像变化检测技术获取机场跑道变化信息,可以为机场跑道打击效果评估等多种军事应用提供决策支撑。为了快速、准确的检测出机场跑道的变化区域,并定量、定性的获得变化属性,文章以"资源三号"卫星影像为例,提出了一种新的面向对象的机场跑道变化检测方法。首先,将经过配准处理的前后时相遥感影像进行多尺度分割,分割尺度利用尺度参数估计(Estimation of Scale Parameters,ESP)算法确定;之后,利用影像分割结果对不同时相的对象进行切割,形成前后时相上位置、大小一致的对象单元,再利用不同时相对象间的变化向量大小确定变化区域;最后,利用特征空间优化之后的特征集合对已确定的变化区域对象进行监督分类,获得机场跑道内部各对象的变化属性。结果表明:在变化区域的检测上,该方法避免了单张影像的分类过程,可有效提高检测效率;在变化类别的检测上,该方法在检测出的变化区域基础上进行分类,可大幅提高变化类别的检测精度,并且能够获得更为丰富的变化属性和满足快速准确检测机场跑道相关变化的信息。     

基于改进Unet++的丘陵地区耕地地块深度分割与提取

丘陵地区耕地地块具有结构复杂、种植类型多样且破碎度高等特点,针对传统分类方法对耕地信息难以快速准确提取的问题,文章基于“高分一号”卫星影像和Unet++网络模型,采用余弦退火学习率实现了复杂丘陵地区耕地信息的准确深度分割和分类。首先利用多尺度分割方法完成了深度迁移学习模型中典型区域耕地样本标签的制作及其结果验证;其次,采用规则格网裁切方法构建影像和标签训练数据集,在PyTorch环境完成了模型的训练;最后,将改进后模型与Unet和SVM方法进行了分类精度和泛化性能的对比分析。结果表明：改进的Unet++网络模型在复杂丘陵地区耕地提取结果的总体精度为92.75%,比SVM和Unet的提取精度分别提高了9.06%和2.50%。因此,基于Unet++的深度学习模型不仅能够有效抑制复杂的背景噪声,还能从遥感影像中学习到更强的语义特征,从而获得更加准确的耕地信息。该方法可为农作物面积监测和产量估算等实际应用提供基础数据支持。     

基于高分卫星姿态监测的姿态参数算法优化

目前航天测绘相机几何参数的在轨标定通常经由地面检校场数据处理完成。然而,由于一次摄影中难以保证获取的地面检校场影像完整,使得在轨标定周期较长,进而导致实时监测与标定非常困难。“高分十四号”卫星搭载了一种新的姿态测定系统,利用高精度的相机光轴监测实现对相机几何参数的在轨实时标定。文章在此基础上对高分卫星星地相机间夹角在轨解算方案进行了优化,并基于数值仿真和在轨实测数据进行了分析,结果显示优化算法可以进一步提高影像内定向稳定度和最终的定位精度,未来有望在高精度立体测绘应用中发挥重要作用。     

环境减灾二号A/B卫星在地震次生地质灾害识别中的应用

以2014年鲁甸地震重灾区为研究区,通过目视解译方法对研究区内的滑坡体进行识别,采用定性评价与定量评价、基础评价与应用评价相结合的方法,对环境减灾二号A/B卫星及高分一号、六号卫星对滑坡的识别能力进行对比分析。结果表明：环境减灾二号A/B卫星可识别出地震后全部大型滑坡、部分中型滑坡和个别小型滑坡。与相同分辨率的高分一号卫星影像相比,环境减灾二号A/B卫星具有相当的滑坡识别能力,并且具有幅宽较大的优势,对于快速识别大型滑坡等地质灾害和确定极灾区范围,具有较好的应用前景。     

“高分一号”卫星首批影像对外发布

国家国防科技工业局今天对外公布"高分一号"卫星获取的首批影像图。据了解,"高分一号"卫星工程大大提升了我国对地观测卫星的总体观测能力,未来将为国土、环境、农业等领域提供精准服务。     

“高分二号”卫星数据在遥感地质调查中的初步应用评价

"高分二号"(GF-2)卫星是迄今为止中国研制的空间分辨率最高的民用遥感卫星,标志着中国民用遥感卫星进入亚米级"高分时代"。为了更好地了解卫星的应用性能,充分发挥和利用好GF-2卫星数据在地质矿产调查工作中的应用,尤其是在条件艰苦地区和境外区域。文章利用GF-2卫星在新疆哈密地区的相关影像数据开展了遥感地质调查应用评价,从数据处理、地质构造信息提取、地层及岩体等岩性信息的识别,以及可识别地质体精度等方面分别进行评价。结果表明,GF-2卫星数据能有效地划分遥感影像地质单元、识别地质构造空间展布特征,很好地满足优于1∶25 000尺度的遥感地质调查工作,可为地质矿产资源调查及评价提供强有力的数据支撑。     

高分一号卫星环境遥感监测应用示范研究

高分一号卫星成功发射以来,在大气环境、水环境和生态环境中的精细化和定量化遥感监测方面发挥了积极作用。作为高分一号卫星的主要用户,环境保护部卫星环境应用中心利用高分一号卫星数据开展了大量应用示范工作,本文以其对气溶胶光学厚度、水华、水质、自然保护区人类活动等遥感监测和评价内容为例,介绍了高分一号卫星在环保领域中的应用示范情况。     

On the stability of the track of the space elevator

A string moving with geostationary angular velocity in its radial relative equilibrium configuration around the Earth, reaching from the surface of the Earth far beyond the geostationary height, could be used as track for an Earth to space elevator. This is an old dream of mankind, originating about 100 years ago in Russia. Besides the question of feasibility from a technological point of view also the question concerning the stability of such a configuration has not yet been completely solved. Under the assumption that a proper material (carbon nanotubes) is available, making the connection possible technologically, we address the question of existence and stability of the radial relative equilibrium of a tapered string on a circular geosynchronous trajectory around the Earth, reaching from the surface of the Earth far beyond the geostationary height.     

On the Possibility of the Existence of Volatile Compounds in the Region of the Scott Crater on the Moon

In this paper, we analyze the illumination conditions, the thermal regime, and the possibility of deposits of volatile compounds existing in the vicinity region (NSR S5 region) near the southern pole of the Moon. It has been found that there are no permanently shadowed zones near the Scott crater and the NSR S5 region, though the temperature conditions allow the of compounds such as CH₃OH, SO₂, NH₃, CO₂, H₂S, C₂H₄, and water to remain stable relative to evaporation for a long time (≥1 Gyr). It has been also shown that compounds like CO and CH₄ cannot stably exist in these regions.     

对老年人体育锻炼负荷量监控方法的探讨

通过对老年人体育锻炼活动的情况进行相关调查，发现目前老年人体育锻炼中存在一些误区。因此本文针对这些现实情况提出，应根据实际情况运用一些简单易行的方法来对老年人体育锻炼实施医务监督，达到提高老年人体育锻炼的科学性。     

Estimation of the current density and analysis of the geometry of the current system surrounding the Earth

The results of an investigation of the distribution of plasma pressure, pressure gradients, and magnetic field near the equatorial plane in the plasma ring surrounding the Earth under magneto-quiet conditions are presented. Observational data obtained during the international THEMIS mission are used. The picture of the distribution of transverse-current density near the equatorial plane was obtained under assumption of observing the magnetostatic balance condition at geocentric distances from 6 to 12R _E. In estimating the integral transverse current it was accepted that in daytime sector the magnetic-field minima on magnetic field lines are not localized in the equatorial plane. Estimates of the integral transverse current were obtained, which demonstrate the possibility of closing nighttime transverse currents at geocentric distances of up to ～12R _E inside the magnetosphere, which form a high-latitudinal continuation of the ring current.     

实施“三位一体”教育模式 提高学生的综合素质

本文介绍了“三位一体”教育模式的内容,描述亍我们实施该模式所采取的措施及取得的成效。实践表明,“三位一体”教育模式能够提高学生的综合素质,为学生毕业后的发展打下坚实基础,对教育模式的改革具有一定的指导意义。     

Estimating the accuracy of the technique of reconstructing the rotational motion of a satellite based on the measurements of its angular velocity and the magnetic field of the Earth

The paper has studied the accuracy of the technique that allows the rotational motion of the Earth artificial satellites (AES) to be reconstructed based on the data of onboard measurements of angular velocity vectors and the strength of the Earth magnetic field (EMF). The technique is based on kinematic equations of the rotational motion of a rigid body. Both types of measurement data collected over some time interval have been processed jointly. The angular velocity measurements have been approximated using convenient formulas, which are substituted into the kinematic differential equations for the quaternion that specifies the transition from the body-fixed coordinate system of a satellite to the inertial coordinate system. Thus obtained equations represent a kinematic model of the rotational motion of a satellite. The solution of these equations, which approximate real motion, has been found by the least-square method from the condition of best fitting between the data of measurements of the EMF strength vector and its calculated values. The accuracy of the technique has been estimated by processing the data obtained from the board of the service module of the International Space Station (ISS). The reconstruction of station motion using the aforementioned technique has been compared with the telemetry data on the actual motion of the station. The technique has allowed us to reconstruct the station motion in the orbital orientation mode with a maximum error less than 0.6° and the turns with a maximal error of less than 1.2°.     

Optimization of the trajectory of the spacecraft insertion into the system of heliocentric orbits

The possibility of the spacecraft insertion into the system of operational heliocentric orbits has been analyzed. It has been proposed to use a system of several operational heliocentric orbits. On each orbit, the spacecraft makes one or more revolutions around the Sun. These orbits are characterized by a relatively small perihelion radius and relatively high inclination, which allows one to investigate the polar regions of the Sun. The transition of the spacecraft from one orbit to another has been performed using an unpowered gravity assist maneuver near Venus and does not require the cruise propulsion operation. Each maneuver transfers the spacecraft into the sequence of operational heliocentric orbits. We have analyzed several systems of operational heliocentric orbits into which the spacecraft can be inserted by means of the considered transportation system with electric propulsion (EP). The mass of the spacecraft delivered to these systems of operational orbits has been estimated.     

从应变计现状看电阻式传感器的前景

电阻式传感器的核心部件——电阻应变计是目前最常用的应力分析的敏感元件。也常用于测量力、压力、扭矩和加速度等物理量。作者简要回顾了电阻应变计的发展历史，介绍了电阻应变计的结构、分类及现状，展望了电阻式传感器的前景。     

System of works on numerical modeling of the dynamics of the structure of the Space Radiotelescope in the RadioAstron project

The results of modeling the dynamics of the Space Radiotelescope are presented. The results of ground-based vibration-dynamic tests are used to validate the calculation models and estimate the damping levels. The dynamic distortions of the reflecting surface caused by the operation of the pointing mechanism of the high-gain antenna are estimated.     

复杂受载条件下固体火箭发动机壳体屈曲应力的估计

论文简略介绍了静力轴压下园柱壳屈曲应力的工程计算方法,对某固体火箭发动机壳体的复杂受载条件对壳体屈曲应力的影响进行了分析,并对该火箭发动机壳体屈曲应力如何估计提出了建议。