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Unknown Environment Measurement Mapping by Unmanned Aerial Vehicle Using Kalman Filter-Based Low-Cost Estimated Parallel 8-Beam LIDAR
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作者 Mohamed Rabik Mohamed Ismail Muthuramalingam Thangaraj +2 位作者 Khaja Moiduddin Zeyad Almutairi Mustufa Haider Abidi 《Computers, Materials & Continua》 SCIE EI 2024年第9期4263-4279,共17页
The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been emplo... The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been employed for this purpose.The accurate detection and mapping of a target such as buildings,trees,and terrains are of utmost importance in various applications of unmanned aerial vehicles(UAVs),including search and rescue operations,object transportation,object detection,inspection tasks,and mapping activities.However,the rapid measurement and mapping of the object are not currently achievable due to factors such as the object’s size,the intricate nature of the sites,and the complexity of mapping algorithms.The present system introduces a costeffective solution for measurement and mapping by utilizing a small unmanned aerial vehicle(UAV)equipped with an 8-beam Light Detection and Ranging(LiDAR)system.This approach offers advantages over traditional methods that rely on expensive cameras and complex algorithm-based approaches.The reflective properties of laser beams have also been investigated.The system provides prompt results in comparison to traditional camerabased surveillance,with minimal latency and the need for complex algorithms.The Kalman estimation method demonstrates improved performance in the presence of noise.The measurement and mapping of external objects have been successfully conducted at varying distances,utilizing different resolutions. 展开更多
关键词 8 beam LiDAR UAV measurement mapping Kalman filter
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Mirror Mapping of Laser Interferometer Measurement System on Ultra-precise Movement Stage 被引量:1
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作者 周云飞 于宝成 《Journal of Southwest Jiaotong University(English Edition)》 2006年第4期355-362,共8页
The accuracy and repeatability of the laser interferometer measurement system (LIMS) are often limited by the mirror surface error that comes from the mirror surface shape and distortion. This paper describes a new ... The accuracy and repeatability of the laser interferometer measurement system (LIMS) are often limited by the mirror surface error that comes from the mirror surface shape and distortion. This paper describes a new method to calibrate mirror map on ultraprecise movement stage (UPMS) with nanopositioning and to make a real-time compensation for the mirror surface error by using mirror map data tables with the software algorithm. Based on the mirror map test model, the factors affecting mirror map are analyzed through geometric method on the UPMS with six digrees of freedom. Dam processing methods including spline interpolation and spline offsets are used to process the raw sampling data to build mirror map tables. The linear interpolation as compensation method to make a real-time correction on the stage mirror unflatness is adopted and the correction formulas are illuminated. In this way, the measurement accuracy of the system is obviously improved from 40 nm to 5 nm. 展开更多
关键词 Laser interferometer measurement system (LIMS) Ultra-precise movement stage (UPMS) Mirror mapping Splineinterpolation Mirror map data tables
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Assessment of Indoor and Outdoor Noise Pollution at a University Hospital Based on Acoustic Measurements and Noise Mapping 被引量:1
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作者 Paulo Henrique Trombetta Zannin Fernanda Ferraz 《Open Journal of Acoustics》 2016年第4期71-85,共15页
This paper describes an analysis of the sound pressure levels at the exterior fa&ccedil;ade and inside the Hospital de Clínicas of the Federal University of Paraná. Measurements were taken at a total of ... This paper describes an analysis of the sound pressure levels at the exterior fa&ccedil;ade and inside the Hospital de Clínicas of the Federal University of Paraná. Measurements were taken at a total of 45 points, 24 at the exterior facade and 21 points inside the hospital on all the floors of the main building and in the maternity building. These 45 measurements were used to calculate the acoustic map of the hospital, which is located on General Carneiro Street, in the city of Curitiba, state of Paraná, Brazil. A comparison of the measured outdoor sound pressure levels against those established by Curitiba Municipal Law No. 10625 revealed that they all exceeded the daytime limit of 55 dB(A) permitted for areas around hospitals. The indoor sound pressure measurements and the noise levels for acoustic comfort established by the Brazilian technical standard ABNT NBR 10152 were compared, indicating that all the measured points, including those in the neonatal intensive care unit, exceeded the established limit of 35 dB(A) to 45 dB(A). 展开更多
关键词 Noise Pollution University Hospital of The Federal University of Paraná Sound measurements Sound Pressure Levels Noise mapping
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First Global Carbon Dioxide Maps Produced from Tan Sat Measurements 被引量:25
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作者 Dongxu YANG Yi LIU +3 位作者 Zhaonan CAI Xi CHEN Lu YAO Daren LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第6期621-623,共3页
1.The need for global carbon monitoring from space and the TanSat mission Global warming is a major problem,for which carbon dioxide(CO2 )is the main greenhouse gas involved in heating the troposphere.However,the po... 1.The need for global carbon monitoring from space and the TanSat mission Global warming is a major problem,for which carbon dioxide(CO2 )is the main greenhouse gas involved in heating the troposphere.However,the poor availability of global CO2 measurements makes it difficult to estimate CO2 emissions accurately. 展开更多
关键词 OCO First Global Carbon Dioxide maps Produced from Tan Sat measurements
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Using fuzzy cognitive maps to model performance measurement system of Internet-based supply chain
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作者 陈娟娟 《Journal of Chongqing University》 CAS 2006年第4期212-217,共6页
Fuzzy cognitive maps (FCM) is a well-established artificial intelligence technique, which can be effectively applied in the domains of performance measurement, decision making and other management science. FCM can b... Fuzzy cognitive maps (FCM) is a well-established artificial intelligence technique, which can be effectively applied in the domains of performance measurement, decision making and other management science. FCM can be a useful tool in a group decision-making environment by using scientifically integrated expert knowledge. The theories of FCM and balance scorecard (BSC) both emphasize cause-and-effect relationships among indicators in a complex system, but few reports have been published addressing the combined application of these two techniques. In this paper we propose a FCM simulation model for the sample performance measurement system of Intemet-based supply chain, which is constructed by BSC theory. We gave examples to explain how FCM can be adapted to execute the causal mechanism of BSC, and also how FCM can support group decision-making and forecasting in performance measurement. 展开更多
关键词 fuzzy cognitive map balanced scorecard supply chain E-BUSINESS performance measurement
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数字填图系统RGMAP在野外实测地质剖面中的应用与方法探索
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作者 蔡金君 周炜 +2 位作者 杨显旭 陈英业 陈星任 《矿产勘查》 2024年第S01期384-389,共6页
数字填图系统(RGMAP)是中国地质调查局开发的数字地质调查系统(DGSS)的移动端系统,能够实现野外实测地质剖面数字化采集,由于手机(掌上机)GPS定位精度易受硬件和环境因素的影响,致使数据精度不足。笔者结合工作实际,简述RGMAP实测剖面... 数字填图系统(RGMAP)是中国地质调查局开发的数字地质调查系统(DGSS)的移动端系统,能够实现野外实测地质剖面数字化采集,由于手机(掌上机)GPS定位精度易受硬件和环境因素的影响,致使数据精度不足。笔者结合工作实际,简述RGMAP实测剖面操作流程和逻辑,分析与传统剖面测量的区别,并进行3种方法测试对比,总结出了一套实测剖面测量方法,实测剖面测量主要通过掌上机进行野外数据采集,融入RTK进行坐标测量,再配合测绳对分层、照片、产状等要素进行控制,辅助确认要素在导线间的位置,该套方法能切实有效地提高工作效率和数据精度。 展开更多
关键词 数字填图 RGmap 实测剖面 应用 方法
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INVARIANT MANIFOLDS AND THEIR STABILITY IN A THREE-DIMENSIONAL MEASURE-PRESERVING MAPPING SYSTEMS
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作者 刘杰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第10期943-950,共8页
In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant cur... In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant curves and invarianttori are obtained,Finally the stability of these in variant manifolds is also discussed. 展开更多
关键词 measure-preserving mapping CHAOS invariant manifold STABILITY
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INVARIANT MANIFOLDS AND THEIR STABILITY IN A THREE-DIMENSIONAL MEASURE-PRESERVING MAPPING SYSTEMS
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作者 刘杰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第5期943-950,共8页
In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant cur... In the paper researches on a three-dimensional measure-preserving mappingsystem are made,which is the three-dimensional extension of the Keplerian mapping.With formal series method the expressions of the invariant curves and invarianttori are obtained,Finally the stability of these in variant manifolds is also discussed. 展开更多
关键词 measure-preserving mapping chaos invariant manifold STABILITY
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T2 mapping眼外肌定量测量在甲状腺相关眼病诊断和分期中的应用价值 被引量:12
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作者 陈文 胡昊 +3 位作者 许晓泉 苏国义 陈欢欢 吴飞云 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2019年第1期141-144,共4页
目的:探讨T2 mapping眼外肌定量测量在甲状腺相关眼病(thyroid-associated ophthalmopathy,TAO)诊断和分期中的价值。方法:对36例TAO患者及28例健康志愿者行眼眶T2 mapping检查,测量眼外肌的T2弛豫时间(T2 relaxation time,T2RT)值。比... 目的:探讨T2 mapping眼外肌定量测量在甲状腺相关眼病(thyroid-associated ophthalmopathy,TAO)诊断和分期中的价值。方法:对36例TAO患者及28例健康志愿者行眼眶T2 mapping检查,测量眼外肌的T2弛豫时间(T2 relaxation time,T2RT)值。比较病例组与正常对照组、活动期组与非活动期组眼外肌T2RT值的差异。采用受试者工作特征曲线(ROC曲线)法评估其判断TAO活动性的诊断价值。结果:病例组眼外肌的T2RT值明显大于正常对照组(P<0.001)。活动期组眼外肌的T2RT值明显大于非活动期组(P<0.001)。ROC结果显示以眼外肌T2RT值≥116.5 ms判断TAO处于活动期的诊断效能最优(曲线下面积0.863,敏感度75.0%,特异度93.8%)。结论:基于T2 mapping的眼外肌定量测量可辅助TAO的诊断和分期。 展开更多
关键词 甲状腺相关眼病 磁共振成像 T2 mapping 定量测量 诊断 分期
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A novel algorithm for distance measurement using stereo camera 被引量:2
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作者 Elmehdi Adil Mohammed Mikou Ahmed Mouhsen 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第2期177-186,共10页
Distance estimation can be achieved by using active sensors or with the help of passive sensors such as cameras.The stereo vision system is generally composed of two cameras to mimic the human binocular vision.In this... Distance estimation can be achieved by using active sensors or with the help of passive sensors such as cameras.The stereo vision system is generally composed of two cameras to mimic the human binocular vision.In this paper,a Python-based algorithm is pro-posed to find the parameters of each camera,rectify the images,create the disparity maps and finally use these maps for distance measurements.Experiments using real-time im-ages,which were captured from our stereo vision system,of different obstacles posi-tioned at multiple distances(60-200 cm)prove the effectiveness of the proposed program and show that the calculated distance to the obstacle is relatively accurate.The accuracy of distance measurement is up to 99.83%.The processing time needed to calculate the distance between the obstacle and the cameras is less than 0.355 s. 展开更多
关键词 computer vision disparity maps distance measurement PYTHON stereoscopic processing
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Consistency Analysis of EKF-based SLAM by Measurement Noise and Observation Times 被引量:14
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作者 LI Hui-Ping XU De-Min ZHANG Fu-Bin YAO Yao 《自动化学报》 EI CSCD 北大核心 2009年第9期1177-1184,共8页
关键词 稠度分析 同步性 映射 滤波器 噪音
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Comparison of Digital Maps: Recognition and Quantitative Measure of Changes
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作者 Lev Spivak Ivan Spivak +1 位作者 Alexey Sokolov Sergey Voinov 《Journal of Geographic Information System》 2014年第5期415-422,共8页
A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of obj... A new methodology of comparing digital raster maps was proposed which allows not only detecting changes in the maps, but also obtaining quantitative measures of the importance of selected differences. Procedure of object interpretation of satellite images and forming of OMT (Object Map of Territory) is described. A list of allowable differences between two OMTs is defined. Two steps technique of quantitative measuring is proposed. At the first stage functions are constructed for calculating local measures of differences in the amount, areas and locations of objects on the map, as well as relations between the objects. In the second stage local measures are used to calculate the integral measure in order to get generalized assessment of difference between maps. The methods for constructing functions which calculate local and integral measures of differences are described. Examples of comparing and measuring the differences between OMTs are provided. Obtained results by utilizing this technique can be used to analyze trends, forecast of development and might be helpful for choosing most efficient scenarios for sustainable spatial planning and land management. 展开更多
关键词 mapS COMPARISON Object map of TERRITORY Change Detection Local measurE of DIFFERENCE INTEGRAL measurE of DIFFERENCE Sustainable Spatial Planning and Land Management
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Measure Synchronization on Symplectic Map
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作者 CHENShao-Ying XUHai-Bo +1 位作者 WANGGuang-Rui CHENShi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期886-894,共9页
Measure synchronization in coupled Hamiltonian systems is a novel synchronization phenomenon. The measure synchronization on symplectic map is observed numerically, for identical coupled systems with different paramet... Measure synchronization in coupled Hamiltonian systems is a novel synchronization phenomenon. The measure synchronization on symplectic map is observed numerically, for identical coupled systems with different parameters. We have found the properties of the characteristic frequency and the amplitude of phase locking in regular motion when the measure synchronization of coupled systems is obtained. The relations between the change of the largest Lyapunov exponent and the course of phase desynchronization are also discussed in coupled systems, some useful results are obtained. A new approach is proposed for describing the measure synchronization of coupled systems numerically,which is advantage in judging the measure synchronization, especially for the coupled systems in nonregular region. 展开更多
关键词 symplectic map measure synchronization phase locking Lyapunov exponent
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Novel Distance Measures on Hesitant Fuzzy Sets Based on Equal-Probability Transformation and Their Application in Decision Making on Intersection Traffic Control
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作者 Fangwei Zhang Yi Zhao +2 位作者 Jun Ye Shuhong Wang Jingyi Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1589-1602,共14页
The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special... The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special way.Firstly,a probability density function is assigned for any given HFE.Thereafter,equal-probability transformation is introduced to transform HFEs with different cardinal numbers on the condition into the same probability density function.The characteristic of this transformation is that the higher the consistency of the membership degrees in HFEs,the higher the credibility of the mentioned membership degrees is,then,the bigger the probability density values for them are.According to this transformation technique,a set of novel distance measures on HFSs is provided.Finally,an illustrative example of intersection traffic control is introduced to show the usefulness of the given distance measures.The example also shows that this study is a good complement to operation theories on HFSs. 展开更多
关键词 Hesitant fuzzy sets equal-probability mapping distance measure intersection traffic control cardinality theory
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A survey of ergodicity on the set-valued mappings
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作者 ZHANGYu-cheng LIAOGong-fu 《海南师范学院学报(自然科学版)》 2004年第4期305-311,共7页
In this paper, we give a survey on the PhD thesis of the first author. There theexistence and ergodicity on invariant measures of set-valued mappings are discused.
关键词 SET-VALUED mapping INVARIANT measure ERGODIC MARKOV operator Mark-ov transition function lower SEMICONTINUOUS continuous selection
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现代测绘技术在矿山地质测绘中的应用探究 被引量:1
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作者 谢正明 《世界有色金属》 2024年第6期159-161,共3页
随着科技的飞速发展,不断转型升级测绘技术,其中以现代化的地矿勘探技术最具代表性。在矿山地质测绘阶段,现代化的测绘技术发挥着重要的作用。在进行矿山地质测绘的实践过程中,工作人员可以结合现代测绘技术和各种测绘设备,详细测量和... 随着科技的飞速发展,不断转型升级测绘技术,其中以现代化的地矿勘探技术最具代表性。在矿山地质测绘阶段,现代化的测绘技术发挥着重要的作用。在进行矿山地质测绘的实践过程中,工作人员可以结合现代测绘技术和各种测绘设备,详细测量和绘制矿山地形地貌,为矿山开挖提供准确的数据。本文主要分析了现代测绘技术在矿山地质测绘中的应用,提出针对性的应用对策,提高矿山地质测绘设计水平,顺利开展相关工作,保障整体工作质量和安全性。 展开更多
关键词 现代测绘技术 矿山地质测绘 应用措施
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健康视域下声景CiteSpace可视化分析
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作者 张洁 左晶 +4 位作者 回腾飞 毛爱欣 宋时屿 祝爱昀 杨智 《北华大学学报(自然科学版)》 CAS 2024年第3期381-396,共16页
收集2000—2023年Web of ScienceTM和CNKI数据库中关于声景与健康的相关文献,利用CiteSpace软件进行可视化文献计量分析,共筛选出544篇有效论文。研究发现:该领域论文数量呈现稳定增长趋势;研究机构整体分布较为分散,尽管单个机构内部... 收集2000—2023年Web of ScienceTM和CNKI数据库中关于声景与健康的相关文献,利用CiteSpace软件进行可视化文献计量分析,共筛选出544篇有效论文。研究发现:该领域论文数量呈现稳定增长趋势;研究机构整体分布较为分散,尽管单个机构内部合作紧密,但跨机构合作尚显不足,互动交流有待加强;研究热点已从初期的环境噪声逐渐转向声景感知,探讨声景与生态效益的关联;声景与健康领域的热门话题表现为多学科多理论相互融合、研究载体日趋细化、研究方法多样化以及新兴技术不断引入。鉴于目前该领域存在的跨学科合作和数字化应用不足,未来研究应更加注重跨学科合作和人工智能等新技术应用,进一步提高对精准度与实践性的重视程度。研究结果揭示了国内外声景与健康研究的总体特点、热点问题及发展趋势。 展开更多
关键词 声景 健康 CITESPACE 知识图谱 文献计量
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测绘工程中三维城市测量技术的应用探究
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作者 单长城 《智能建筑与智慧城市》 2024年第9期52-54,共3页
三维城市测量技术可以帮助城市规划师和建筑师更加准确地了解城市的地形、建筑物高度、道路宽度以及其他重要数据。文章先概述了测绘工程中的三维城市测量技术,然后对其技术应用积极能效进行论述,最后对其技术的实践应用进行研究。
关键词 测绘工程 三维城市 测量技术
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基于Photo Sphere Viewer的轻量化可量测街景系统研究
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作者 刘一宁 王琳 岳照溪 《测绘通报》 CSCD 北大核心 2024年第S01期11-17,共7页
随着新型基础测绘体系发展,测绘技术和装备不断升级,大量街景数据随着车载激光扫描工作一并被采集。针对该数据路线随机性大、密集程度高等特点,以及传统街景地图系统插件受限、扩展性不强、无法量测等局限,本文设计了基于Photo Sphere ... 随着新型基础测绘体系发展,测绘技术和装备不断升级,大量街景数据随着车载激光扫描工作一并被采集。针对该数据路线随机性大、密集程度高等特点,以及传统街景地图系统插件受限、扩展性不强、无法量测等局限,本文设计了基于Photo Sphere Viewer的轻量化可量测街景系统,在开源插件的基础上实现了对其组件的扩充、实现了行进方向、地图交互等系统功能的设计优化,进一步实现了基于深度图的街景地图量测功能。生产作业队伍对系统的使用结果表明,该系统可以辅助生产作业队伍进行属性采集、纹理更新、数据检查等多项工作,操作灵活便捷,且具有较强的可扩展性,便于基于生产需求进行改进调整,提高了生产效率,为新型基础测绘成果进一步深化应用提供了良好的借鉴作用。 展开更多
关键词 Photo Sphere Viewer 轻量化 街景量测 街景数据组织 新型基础测绘
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基于车载三维激光扫描的城市道路竣工测量探讨
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作者 贾峻峰 《科技资讯》 2024年第2期142-144,共3页
车载三维激光扫描系统融合了多种传感器和数据源,可以自动、迅速地获取道路的全方位信息。其扫描速度迅捷、数据信息丰富、精确度高、采集过程安全简单,并能节省人力。此技术显著提高了外业生产效率,并降低了生产成本。对车载三维激光... 车载三维激光扫描系统融合了多种传感器和数据源,可以自动、迅速地获取道路的全方位信息。其扫描速度迅捷、数据信息丰富、精确度高、采集过程安全简单,并能节省人力。此技术显著提高了外业生产效率,并降低了生产成本。对车载三维激光扫描技术在道路工程竣工测量中的内外业处理流程的研究结果表明:该技术的精度可达到1∶500测图精度要求,满足城市高架路竣工规划测绘的精度需求。该技术方案是切实可行的,且能高效地提高生产效率。 展开更多
关键词 车载三维激光扫描 道路竣工测量 点云数据精度 测图精度
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