中国面向遥感应用的垂直起降无人机现状和 应用前景分析

近年来,针对中国生态环境、洪涝灾害应急响应、国土安全监测等遥感观测任务,无人航空遥感手段需求越来越多。构建异构无人航空器遥感观测多任务集群系统是近几年的发展目标,为完成无人航空遥感生态建设,垂直起降无人机以其不受场地限制起降又可快速巡飞的特点,在多个领域发挥着越来越大的作用。本文主要研究内容包括国内垂直起降无人机发展现状调研、面向航空遥感应用市场的无人机分析及典型机型介绍、垂直起降无人机在遥感领域的应用场景及案例分析、垂直起降无人机在遥感领域的应用前景及发展趋势等。通过广泛调研及深入分析可知,目前垂直起降固定翼无人机正逐步取代多旋翼飞行器的主导地位;垂直起降无人机占据了遥感应用无人机80.47%的市场份额;动力多元化、系统智能化、布局多样化、尺寸小型化等是面向遥感应用的垂直起降无人机的发展方向。本文较为全面地阐述和剖析了面向遥感应用的垂直起降无人机的相关内容,为遥感航空无人机生态建设提供了参考与支撑。     

鞍山3.3Ga陈台沟花岗岩地球化学和Nd、Pb同位素特征

地球化学和Ｎｄ、Ｐｂ同位素研究表明，鞍山地区陈台沟花岗岩不是早期古老陆壳物质壳内再循环的产物，而是同时代亏损地幔提取物（变玄武质岩石）在短时间内发生再次熔融的结果，形成过程中受到古老陆壳物质的混合混染。３．１５±Ｇａ是鞍山地区地质演化过程的一个重要阶段，它使陈台沟花岗岩的长石Ｐｂ和全岩Ｐｂ发生再次均匀化。３．３Ｇａ的花岗质岩石在鞍山弓长岭地区也有分布，它们来自于与陈台沟花岗岩类似的物源区，但形成条件可能并不完全相同。     

内蒙古白云鄂博稀土、铁矿床的硅同位素组成

主矿、东矿矿石及其中的钠辉石、钠闪石、黑云母的δ30Si值相近，大多在-1.0‰--0.3‰之间，低于H1-H2石英砂岩、石英岩的δ30Si值（0-0.1‰）。北铁矿石为0-0.1‰，北矿区塞乌素金矿的δ30Si值为-0.5%--0.2‰；它们之间无成因联系。     

岛礁附近浮式平台运动响应特性数值分析

利用基于开源平台Open FOAM自主开发的船舶与海洋工程水动力性能求解器naoe-FOAM-SJTU,数值模拟了近岛礁环境下规则波的演化特性以及带有系泊系统的浮式平台在相应波浪作用下的水动力性能。对于平台的水动力性能的研究发现,仿真结果与试验结果在平台自由衰减运动固有周期及RAO(response amplitude operator)方面吻合良好。对于波浪在近岛礁地形下的演化现象的研究,分析了波浪演化不对称性特性的成因,并分别给出了不同参数下波浪在地形上爬升时演化的具体特性,对于波高变化及波浪演化的频率成分进行量化的探究。研究发现,波浪周期越大,波高变化越明显,演化的非线性现象越明显,且波浪随着传播距离的增大演化出的阶数也在增大。     

THE STATIC STRESS TRIGGERING INFLUENCES OF THE 2015 MW6.4 PISHAN,XINJIANG EARTHQUAKE ON THE NEIGHBORING AREAS

Based on the rupture models of the 2015 Pishan M_W6.4 earthquake and half space homogeneous elastic model, the Coulomb stress changes generated by the earthquake are calculated on the active faults near the earthquake region. The horizontal stress changes and the displacement field are estimated on the area around the epicenter. Results show that:(1)The Coulomb stress is decreased in the west of the western Kunlun frontal thrust fault(9.5×10³Pa), and increased in the east of the western Kunlun frontal thrust fault and the middle of the Kangxiwa faults. More attention should be taken to the seismic rick of the east of the western Kunlun frontal thrust fault; (2)Based on the analysis on the location of the aftershocks, it is found that most of the aftershocks are triggered by the earthquake. In the region of increased Coulomb attraction, the aftershock distribution is more intensive, and in the area of the Coulomb stress reduction, the distribution of aftershocks is relatively sparse; (3)The horizontal area stress increases in the north and south of the earthquake(most part of the Qaidam Basin and the northwest of the Qinghai-Tibet plateau), and decreases in the east and west of the earthquake(northern part of the Qinghai-Tibet plateau and eastern part of the Pamir Mountains). In the epicenter area, the principal compressive stress presents nearly NS direction and the principal extensional stress presents nearly EW direction. The principal compressive stress shows an outward radiation pattern centered on the epicenter with the principal extensional stress along the direction of concentric circles. The principal compressive stress presents NW direction to the west of the epicenter, and NE to the east of the epicenter. With the increase of radius, the stress level gradually decays with 10⁷Pa in the epicenter and hundreds Pa in the Maidan Fault which is in the north of the Qaidam Basin.     

老滑坡和断层影响下滑坡特征及处治措施研究

滑坡是我国最常见的地质灾害之一.老滑坡体加上断层破碎带的影响往往导致工程滑坡成因机理更为复杂.针对广东大潮高速公路K20工点滑坡案例的破坏情况,通过现场调研和地质勘测确定该滑坡工程的变形特征,探讨了受老滑坡及断层带控制的滑坡致灾机理,并且对该处滑坡进行了稳定性分析.结果表明:该处为老滑坡地貌,地质构造是形成老滑坡的控制...     

关岭自治县气候特点简介

从地理位置、地形地貌和气温、降水、日照等气象要素方面分析,介绍关岭县的气候特点,为推进我县生态农业建设、招商引资工作提供决策参考依据。     

基于Siamese卷积神经网络的影像瓦片变化检测技术

针对地理信息变化较快而传统更新方式效率不高的问题,目前许多学者提出了各类变化检测的方法,但这些方法大都是基于影像数据进行试验,对影像预处理要求较高,且检测精度的稳定性较差,受数据源质量影响较大。而天地图、百度地图、谷歌地图等地图中均可免费下载各种级别的影像瓦片,因此本文提出利用天地图影像瓦片进行试验,采用Siamese卷积神经网络（SCNN）和深度学习技术,开发基于SCNN的高精度变化监测算法,以快速发现变化区域,实现地理信息变化信息检测。     

美国海军应对未来水下战的装备发展分析

伴随反介入/区域拒止武器的发展,美国海军与其他大国海军的水面优势越来越小,水下战场成为美国海军展示军事力量、获得战场主动权所倚重的手段。目前,水下战已成为美国海军重点发展的领域之一。通过对美国海军水下战作战概念发展历程的梳理,分析研究了其未来水下战所面临的新威胁挑战。结合美国海军的具体实际,研究给出了美国海军应对未来水下战的装备发展。     

Three-dimensional structure of a low salinity tongue in the southern Taiwan Strait observed in the summer of 2005

Cruise observations with CTD (conductivity-temperature-depth) profiler were carried out in the southern Taiwan Strait in the summer of 2005. Using the cruise data, two-dimensional maps of salinity and temperature distributions at depths of 5, 10, 15, 20, and 30 m were generated. The maps show a low salinity tongue sandwiched by low temperature and high salinity waters on the shallow water side and high temperature and high salinity waters on the deep water side. The further analysis indicates that the low salinity water has a nature of river-diluted water. A possible source of the diluted water is the Zhujiang (Pearl) Estuary. Meanwhile, the summer monsoon is judged as a possible driving force for this northeastward jet-like current. The coastal upwelling and the South China Sea Warm Current confine the low salinity water to flow along the central line of the strait. Previous investigations and a numerical model are used to verify that the upstream of the low salinity current is the Zhujiang Estuary. Thus, the low salinity tongue is produced by four major elements:Zhujinag Estuary diluted water, monsoon wind driving, coastal upwelling and South China Sea Warm Current modifications.