浅谈GIS在国民经济建设中的应用

本文介绍了GIS的起步、发展、功能,浅谈GIS在我国水利、农业、城市建设、军事等行业的应用现状,介绍了GIS在政府决策、98抗洪等方面的应用,并列举了有利于GIS持续发展的条件。     

3S技术在苹果园信息化中应用研究的进展与展望

针对目前信息技术在苹果园管理上存在应用水平不高、应用简单化、缺乏系统的基础研究等问题,本文以"农业信息化"和"数字果园"的定义为基础,提出了"苹果园信息化"的概念,对3S技术在苹果园信息采集、苹果质量检测、营养诊断、病虫害治理、信息系统研发等方面的应用研究进行了详细总结,根据存在的问题提出了加强3S集成技术应用、研发实用的信息化技术装置等可行性建议。     

天津市建筑市场监管GIS应用中的关键技术研究

阐述了GIS在天津市建筑市场监管系统中的应用情况,介绍了在目前的建筑市场监管BS系统的业务基础上,应用地理信息的各项技术对各类建筑企业和工程项目的数据采集、空间分析等功能的实现,详细论述了其中关于Silverlight地图、嵌入式应用、空间数据库等关键技术的应用情况。     

手机室内定位的应用与服务

随着智能手机的普及,基于手机的室内定位应用越来越受到各界的关注,并在各个领域得到快速的应用。基于手机的室内定位技术在商业广场线上线下融合、安全监控、个人服务等方面都有着极为核心的作用。首先介绍了室内位置服务应用平台的架构体系,其次介绍了手机室内定位的常用技术及其基本原理,最后介绍了室内定位在商场、机场、个人服务等方面的典型应用,并进行了总结。     

3S技术集成在国土管理工作中的应用

介绍了3S技术的发展;3S集成技术在国土管理工作中的应用,包括基于3S技术的土地利用变更调查、利用3S技术进行地形数据库的更新、3S技术在土地利用动态监测中的应用、3S技术在土地资源规划中的应用、3S技术在土地可持续利用决策中的应用等;最后介绍了运用3S集成技术推进土地管理工作现代化等。     

基于三维空间的电力设施灾害数据挖掘

近年来,随着电子、计算机等技术的飞速发展,三维GIS的应用渐趋成熟,以往设想中的许多应用逐渐成为了现实。比如城市应急反应、虚拟旅游、智能交通、城市规划与设计等领域中,三维GIS都有广泛成熟的应用。尤其是在电力行业的应用中,三维技术除了能更好地展现三维场景、电力模型等,还能够和灾害模型相结合,进行电力设施灾害结果预测等。本文提出的基于三维空间的灾害数据挖掘方法,涉及灾害分布空间分析和空间数据挖掘的方法,是一种在三维地理信息技术下灾害分布情况对于电力设施影响程度的数据挖掘方法。     

地下工程陀螺定向测量软件开发

陀螺经纬仪是一种利用陀螺原理自主寻北的测量仪器,兼有定向与测角功能。由于其定向精度高、不受气候条件限制、全天候的自主定向等特点,在军事、测绘、地下工程、矿山等领域有着广泛的应用。以地下工程陀螺定向测量应用为背景,设计地下工程陀螺定向测量软件,研究陀螺经纬仪在地下工程陀螺定向测量应用中的相关问题。     

物联网应用在GIS中需要解决的若干技术问题

作为由多种异构终端密集部署在各个地方构成的一种协同自组织的网络应用系统,物联网具有规模巨大、形式复杂、实时异构、形式多样等特点。本文从异构网络互联、多源数据融合、物联数据模型和信息感知应用等4个方面讨论将物联网应用到GIS领域需要解决的基础理论和技术方法,并通过应用实例说明了物联网与GIS技术结合应用实现的技术方法。     

基于物联网的城市管理统一业务受理平台设计与应用

物联网技术在智慧城市发展中得到深化研究与应用,综合监控与处置物联网监测报警,对最终意义上实现城市管理可持续发展具有重要应用价值。本文结合项目实践应用阐述平台的研究设计思路,介绍数据实时统一分类监管,移动终端闭环处置流程,数据动态跟踪更新表达等内容,对SignalR实时通信、Vue动态更新、移动端相关服务等关键技术应用进行说明。该平台在安徽宿州智能管网PPP项目中应用成效显著。     

编者的话

稀土被誉为是工业的"味精",是不可再生产的重要战略资源,在新能源、新材料、节能环保、航空航天、电子信息等领域的应用日益广泛。我国是稀土被誉为是工业的"味精",是不可再生产的重要战略资源,在新能源、新材料、节能环保、航空航天、电子信息等领域的应用日益广泛。我国是稀土被誉为是工业的"味精",是不可再生产的重要战略资源,在新能源、新材料、节能环保、航空航天、电子信息等领域的应用日益广泛。我国稀土被誉为是工业的"味精"     

HJ-1光学卫星遥感应用前景分析

HJ-1星座光学卫星作为我国环境与灾害监测预报小卫星星座的首发卫星,其运行与应用状况对于后续星座的发展具有重要 的理论和实践指导意义。本研究从HJ-1光学卫星的分辨率（时间、空间和光谱）、光谱及幅宽等数据特征入手,综合考虑遥感应用 数据要求,全面分析评价HJ-1光学卫星数据可用性。研究表明,两颗光学卫星可基本满足我国及周边国家环境监测与灾害管理方面 的主要应用需求,并在其它领域也具有广阔的应用前景。     

测绘新技术在城市新基建模型构建中的融合应用

空间信息基础设施建设是新基建内容中的重要组成部分,随着测绘技术的快速发展,遥感卫星、无人机、移动测量车等新型测绘装备不断普及;此外,物联网技术在新基建浪潮下也得到广泛应用。基于此,本文介绍了采用地面移动测量与倾斜摄影技术融合的方法构建三维精细模型,同时在模型中引入物联网数据和BIM数据,实现了城市新基建模型的构建。在此基础上,实现了城市新基建模型在桥梁变形监测方面的应用,为智慧城市的建设提供借鉴。     

Beidou satellite maneuver thrust force estimation for precise orbit determination

Beidou satellites, especially geostationary earth orbit (GEO) and inclined geosynchronous orbit (IGSO) satellites, need to be frequently maneuvered to keep them in position due to various perturbations. The satellite ephemerides are not available during such maneuver periods. Precise estimation of thrust forces acting on satellites would provide continuous ephemerides during maneuver periods and could significantly improve orbit accuracy immediately after the maneuver. This would increase satellite usability for both real-time and post-processing applications. Using 1 year of observations from the Multi-GNSS Experiment network (MGEX), we estimate the precise maneuver periods for all Beidou satellites and the thrust forces. On average, GEO and IGSO satellites in the Beidou constellation are maneuvered 12 and 2 times, respectively, each year. For GEO satellites, the maneuvers are mainly in-plane, while out-of-plane maneuvers are observed for IGSO satellites and a small number of GEO satellites. In most cases, the Beidou satellite maneuver periods last 15–25 min, but can be as much as 2 h for the few out-of-plane maneuvers of GEO satellites. The thrust forces acting on Beidou satellites are normally in the order of 0.1–0.7 mm/s². This can cause changes in velocity of GEO/IGSO satellites in the order of several decimeters per second. In the extreme cases of GEO out-of-plane maneuvers, very large cross-track velocity changes are observed, namely 28 m/s, induced by 5.4 mm/s² thrust forces. Also, we demonstrate that by applying the estimated thrust forces in orbit integration, the orbit errors can be estimated at decimeter level in along- and cross-track directions during normal maneuver periods, and 1–2 m in all the orbital directions for the enormous GEO out-of-plane maneuver.     

陆地卫星遥感监测体系及应用前景

我国陆地卫星的快速发展和人工智能等高新技术的广泛应用为重构卫星遥感监测体系奠定了重要基础。针对我国自然资源保护、国土空间规划实施监督、生态修复及全球变化研究等对土地利用、土地覆盖及其相关地表参数指标动态变化信息的需求,基于当前我国陆地卫星观测能力,设计了全球宏观尺度监测及我国陆域范围季度监测、重点区域月度监测及应急事件即时响应的卫星遥感监测体系框架;针对自然资源卫星遥感监测需求,充分运用大数据、人工智能、云计算等高新技术,本文提出了基于工作流的监测生产线智能流转与可插拔模块调度控制、遥感影像样本知识库构建、复杂场景自然资源变化自动提取、自然资源特定目标自动提取和自然资源变化图斑全生命周期管理等技术解决方案,构建了遥感监测业务化应用技术流程,实现了我国陆域范围自然资源全要素季度监测、重点区域高频次精准监测、特定目标即时监测能力,并在自然资源执法督察和地表水变化等监测中得到应用。     

Thermal re-emission effects on GPS satellites

Highly precise satellite-derived coordinates depend on accurate orbit predictions, which cannot be achieved with purely empirical models. Global positioning system (GPS) satellites undergo several periodic perturbing forces that have to be modeled and understood. In this scenario, small non-gravitational forces can no longer be neglected when the purpose of the orbital analysis is to obtain accurate results (Vilhena de Moraes 1994). Together with solar radiation pressure, thermal re-emission effects due to solar heating and Earth albedo are the two most important non-gravitational effects. While solar radiation pressure is widely understood, our knowledge about thermal re-emission effects on GPS satellites is in its infancy. Few models have been proposed in recent years and despite the interest of the scientific community, there is a lack of detailed results concerning the magnitude and the behavior of such forces. The aim of this work is to provide a thermal re-emission force model for GPS satellites, simple enough to minimize the problem of modeling a satellite of complex shape with several components on its surface, but accurate enough to provide an estimate of the magnitude and the behavior of these forces, as well as to provide some input to the present knowledge about photon thrust on GPS satellites. Some results of this work point to the fact that thermal re-emission effects are good candidates to partially explain the Y-bias for GPS satellites.     

Small satellites for global coverage: Potential and limits

There is an increasing need for Earth Observation (EO) missions to meet the information requirements in connection with Global Change Studies. Small and cost-effective missions are powerful tools to flexibly react to information requirements with space-borne solutions. Small satellite missions can be conducted relatively quickly and inexpensively by using commercial off-the-shelf-technologies, or they can be enhanced by using advanced technologies. A new class of advanced small satellites, including autonomously operating “intelligent” satellites may be created, opening new fields of application. The increasing number of small satellites and their applications drive developments in the fields of small launchers, small ground station networks, cost-effective data distribution methods, and cost-effective management and quality assurance procedures. There are many advantages of small satellite missions, like more frequent mission opportunities, a faster return of data, larger variety of missions, more rapid expansion of the technical and/or scientific knowledge base, greater involvement of small industry, feasibility by universities and others.This paper deals with general trends in the field of small satellite missions for Earth observation. Special attention is given to the potential of spatial, spectral, and temporal resolution of small satellite based systems. Examples show small satellites offer also the unique possibility to install affordable constellations to provide good daily coverage of the globe and/or allow us to observe dynamic phenomena.The facts and examples given in this paper lead to the conclusion: Small satellites are already powerful tools for monitoring global, regional and local phenomena. In the future, their application spectrum will even broaden based on the ongoing development in many areas of technology and observation techniques.     

利用SNR观测值进行GPS土壤湿度监测

利用GPS信噪比(SNR)观测值监测土壤湿度变化可克服传统手段破坏观测对象、数据难以同化、时空分辨率受限等缺点,但同时也存在测量区域不明确、卫星与波段选择缺少相应依据、多径延迟相位与土壤湿度之间相关性的定量数值描述函数与模型亟待建立等问题。本文通过引入菲涅尔反射区域,结合仿真和实测土壤湿度数据、GPS观测值开展对比实验对上述问题进行研究。实验过程及结果表明,采用SNR观测值能有效跟踪土壤湿度的变化趋势,最大有效测量范围约45m,利用指数函数能较好地描述SNR多径延迟相位与土壤湿度之间的关系。同时,选择高级卫星和记录L2C观测值,有利于获得更准确的结果。     

基于资源三号卫星影像的城市绿地信息提取方法探讨

我国高分遥感卫星的发展为城市绿地的规划、建设和改造提供有力的技术支持。研究利用资源三号卫星全色和多光谱影像,以国内某城市为例,采用基于规则的面向对象分类技术获取城市绿地。研究提出的技术方案,简单易行,具有较好的应用性。对于推动资源三号卫星在国土资源和城市规划方面的应用具有重要意义。     

关于建设北斗星基广域增强系统研究

鉴于GPS系统已经成熟,北斗导航系统建设尚不完善,本文考虑建设北斗卫星对GPS卫星的增强系统。一方面,采用GPS/Compass-Ⅱ组合卫星导航系统,可大大增加某一时刻的可见卫星数,增强导航定位系统的可靠性。另一方面,北斗现已发射第九颗导航卫星,其中包括5颗地球静止轨道卫星,本文重点探讨利用这5颗GEO(Geostationary Orbit,GEO)卫星对GPS系统进行外部增强,即北斗GEO卫星同时播发卫星导航电文和增强信息,提高用户定位精度。     

Equal-Area Projections of the Triaxial Ellipsoid: First Time Derivation and Implementation of Cylindrical and Azimuthal Projections for Small Solar System Bodies

Many small solar system bodies such as asteroids or small satellites have irregular shapes, often approximated by the reference surface of a triaxial ellipsoid. Map projections for the triaxial ellipsoid are needed to present the incoming data in the form of maps. In this paper the formulae of equal-area cylindrical and azimuthal projections of the triaxial ellipsoid were derived and practically implemented for the first time using as an example the asteroid 253 Mathilde. This paper is the final in a series of papers devoted to all main classes of projections of the triaxial ellipsoid. Before this, the authors obtained equidistant along meridians projection and Jacobi conformal projection for the triaxial ellipsoid.