搜索结果: 61-75 共查到“知识库 光电子学与激光技术”相关记录1641条 . 查询时间(2.25 秒)
Filining Lacunas in Terrestrial Laser Scanning Data: The "Cavallo Ligneo" of the "Palazzo Della Ragione" (Padua, Italy)
Laser scanning Cultural Heritage Application Reconstruction Modelling
2015/11/13
Laser scanning methodology allows to reconstruct the metric characteristics of objects at different LOD (Level Of Detail) providing spatially dense points clouds. In particular, the terrestrial applic...
Surveying and Documentation of Detailed Historical Heritage by Laser Scanning
Terrestrial Laser Scanner Historical Heritage Documentation Point Cloud
2015/11/13
In this research, surveying and documentation of historical heritage has been aimed by using laser scanning. Developing technologies has brought out in surveying and documentation of historical herita...
3D Laser Scanner and Reflectorless Total Station:A Comparative Study of the Slots of El-Khazneh at Petra in Jordan
Compression Laser scanning Application Accuracy Point Cloud
2015/11/13
Today, the laser scanners are widely used in the field of architectural, archaeological and environmental surveying because of their practicality and flexibility. A laser scanning machine can be consi...
Towards Creating a Dialogue Between the Specialized Technician and non Technician Users of the 3D Laser Scanner
Laser scanning Generalization Recording Simplification Accuracy User Understanding Point Cloud
2015/11/13
Several attempts and case studies had been conducted to document the cultural heritage using the 3D Laser scanner in the last few years. Now, it is possible to furnish a virtual model of an object fro...
Laser Scanner and Architectural Accuracy Text
Laser scanner accuracy test architectural survey cultural heritage
2015/11/13
In last years laser scanning have increased its application in different fields: from geological to architectural and archaeological survey, from real time monitoring to rapid prototyping. Respect to ...
Laser Scanning for Historical and Geotechnical Studies at Pointe du Hoc
Laser Scanning WWII Cliffs Erosion Resistivity
2015/11/13
The Pointe du Hoc Historic Site, in Normandy, France was host to one of the most important battles of D-Day. Its importance is marked by the bravery of the men of the 2nd Ranger Battalion who scaled i...
Documentation of the Geometry and Earlier Interventions of the Ancient Theater Of Dodona
Dodona ancient theater restoration laser scanning Digital Terrain Model
2015/11/12
The implementation of the Digital Terrain Model which was produced after Laser Scanning of the theatre of Dodona resulted in numerous valuable information about the architecture and the history as wel...
Automated Modelling of Surface Detail from Point-Clouds of Historical Objects
Laser scanning Surface Modeling Triangulation Monitoring Cultural Heritage
2015/11/12
Terrestrial Laser Scanners are well suited for the acquisition of data for subsequent geometric modeling. Modern phase shift laser scanners allow the measuring of point clouds with very high point den...
880nm同带泵浦的高效率Nd:YVO4自拉曼激光器
自拉曼激光器 同带泵浦 Nd:YVO4激光器
2016/7/27
利用880 nm半导体激光器同带泵浦声光调Q Nd:YVO4自拉曼激光器,以减轻热效应对泵浦功率的限制和对拉曼增益的影响,获得高效的1 176 nm一阶斯托克斯光输出。使用两块长度10 mm的Nd:YVO4晶体作为增益介质,脉冲重复频率190 kHz时,在26.8 W入射泵浦功率下获得6.11 W的平均输出功率,光光转换效率22.8%。实验研究了拉曼增益介质长度对输出功率和转换效率的影响,并对自拉...
大气散射效应是影响星载激光测高仪接收脉冲回波的重要因素。根据星载激光测高仪接收脉冲回波信号与大气响应函数之间的关系式,在忽略大气多次散射效应的条件下,通过分析散射激光束的几何轨迹和散射概率,推导出单次大气散射激光脉冲和接收脉冲回波的特征参数的数学解析式。以地球科学激光测高仪系统参数为输入,采用数值仿真分析的方法,模拟了大气散射介质分布、激光指向角和目标倾斜角对接收脉冲回波信号特征参数的影响。结果表...
强激光水下爆炸推进的物理机制
激光水下聚焦爆炸推进 激光诱导等离子体 气泡脉动 物理模型 数值模拟
2018/12/29
对激光水下聚焦爆炸推进的作用机理开展了实验测量和数值模拟研究. 实验观察到激光水下聚焦爆炸推进分为两个物理过程: (1) 强激光与铝膜相互作用诱导等离子体演化, 产生短脉冲、高幅值的等离子体压力, 并对航行体做功; (2) 激光爆炸产物气泡脉动, 对航行体继续提供推力. 另外, 实验还对不同介质中的激光推进效率以及气泡与约束壁面/自由水面相互作用的物理机制进行了研究. 发现在高阻抗环境介质、气泡受...
干扰条件下制导波门对激光信号录取的数学仿真
联合概率密度分布函数 角度欺骗干扰 波门 录取概率 Monte-Carlo模拟
2016/7/27
波门是激光制导中广泛采用的一种抗干扰措施,其对干扰信号录取概率的大小对干扰成功与否非常关键。依据制导信号与干扰信号在波门内既相互联系又相互独立的特点,提出可用干扰信号与制导信号的联合概率密度函数描述干扰条件下波门对激光信号的录取,同时需要考虑干扰信号对实时波门的牵引作用。运用Matlab软件仿真了不同宽度的实时波门录取干扰信号的概率与超前同步时间的关系,表明对宽度一定的实时波门存在一个最佳的超前同...
切伦科夫辐射的强流电子束均匀性光学诊断
强流电子束 时间分辨均匀性诊断 高速分幅相机
2016/7/15
透明介质中带电粒子的运动速度大于介质中的光速时就会产生切伦科夫辐射光。搭建了基于切伦科夫辐射光的强流电子束均匀性诊断系统，实现了时间和空间分辨的纳秒级电子束均匀性光学诊断。利用程序对诊断系统进行设计。在此基础上对两种天鹅绒阴极发射均匀性进行光学诊断测量。结果表明：在相同电参数下，碳纤维天鹅绒较化纤天鹅绒具有更好的发射性能，与之对应的切伦科夫辐射光斑面积更大，其亮度扫描曲线不但中心增强区域较化纤天鹅...
杂散参数对串联型磁脉冲压缩器输出特性的影响
脉冲功率技术 磁脉冲压缩器 杂散参数
2016/7/15
使用电路模拟软件分析了脉冲电容器自身电感、磁开关绕组匝间电容以及磁芯处于不同工作状态时磁开关绕组自身阻抗等杂散参数对串联型磁脉冲压缩器输出特性的影响。结果表明，匝间电容和磁芯处于未饱和状态下的绕组自身阻抗对系统的输出特性影响相对较小；磁芯处于饱和状态时，绕组自身阻抗对系统的电压传输效率影响较大；脉冲电容器的自身电感不仅会降低系统的电压传输效率，而且会同时影响到输出脉冲上升沿的宽度。基于以上结论，对...