Efficiently capturing large,complex cultural heritage sites with a handheld mobile 3D laser mapping system     

《Journal of Cultural Heritage》2014,15(6):670-678

Accurate three-dimensional representations of cultural heritage sites are highly valuable for scientific study, conservation, and educational purposes. In addition to their use for archival purposes, 3D models enable efficient and precise measurement of relevant natural and architectural features. Many cultural heritage sites are large and complex, consisting of multiple structures spatially distributed over tens of thousands of square metres. The process of effectively digitising such geometrically complex locations requires measurements to be acquired from a variety of viewpoints. While several technologies exist for capturing the 3D structure of objects and environments, none are ideally suited to complex, large-scale sites, mainly due to their limited coverage or acquisition efficiency. We explore the use of a recently developed handheld mobile mapping system called Zebedee in cultural heritage applications. The Zebedee system is capable of efficiently mapping an environment in three dimensions by continually acquiring data as an operator holding the device traverses through the site. The system was deployed at the former Peel Island Lazaret, a culturally significant site in Queensland, Australia, consisting of dozens of buildings of various sizes spread across an area of approximately 400 × 250 m. With the Zebedee system, the site was scanned in half a day, and a detailed 3D point cloud model (with over 520 million points) was generated from the 3.6 hours of acquired data in 2.6 hours. We present results demonstrating that Zebedee was able to accurately capture both site context and building detail comparable in accuracy to manual measurement techniques, and at a greatly increased level of efficiency and scope. The scan allowed us to record derelict buildings that previously could not be measured because of the scale and complexity of the site. The resulting 3D model captures both interior and exterior features of buildings, including structure, materials, and the contents of rooms.  相似文献   

激光扫描技术在自由式滑雪运动员三维人体模型建立中的应用     

关欣  王新  白巍  付彦铭 《广州体育学院学报》2014,(1):92-95

为了缩短体育运动中人体运动技能分析过程人体模型构建周期和提高构建精度。采用激光扫描 技术,对自由式滑雪运动员在助滑阶段的几个主要动作进行数据采集,以“实物-设计意图-三维重构-再 设计”框架为流程,建立自由式滑雪运动员三维人体模型。研究发现在采用激光扫描技术得到表面的几何 数据基础上,人体模型的构建还要经过数据拼合、简化、三角化、去噪等预处理,再进行测量数据分块、 曲面拟合,最终进行模型重构。探讨了运动生物力学研究领域人体模型构建的新方法,提高人体模型构建 效率,为体育科学人体运动研究提供基础模型。  相似文献   

基于改进灰色神经网络模型的三峡枢纽过坝货运量预测     

柯桥  邓萍 《上海海事大学学报》2021,42(1):82-87

针对三峡枢纽过坝货运量预测受多种因素影响及其具有的非线性特点,提出一种基于改进灰色模型和神经网络的组合预测模型。针对传统组合预测模型在赋权上的局限性,提出基于诱导有序加权几何平均(induced ordered weighted geometric averaging,IOWGA)算子的赋权方法。计算结果比较:组合预测模型的均方误差和均方百分比误差都比各单一预测模型的小。利用组合预测模型对2019—2022年三峡枢纽过坝货运量进行了预测,可为相关决策者提供参考。  相似文献   

Application of near-infrared spectroscopy to predict sweetpotato starch thermal properties and noodle quality   总被引：2，自引：0，他引：2  

Lu GQ  Huang HH  Zhang DP 《Journal of Zhejiang University. Science. B》2006,7(6):475-481

Sweetpotato starch thermal properties and its noodle quality were analyzed using a rapid predictive method based on near-infrared spectroscopy （NIRS）. This method was established based on a total of 93 sweetpotato genotypes with diverse genetic background. Starch samples were scanned by NIRS and analyzed for quality properties by reference methods. Results of statistical modelling indicated that NIRS was reasonably accurate in predicting gelatinization onset temperature （To） （standard error of prediction SEP=2.014 ℃, coefficient of determination RSQ=0.85）, gelatinization peak temperature （Tp） （SEP=-1.371 ℃, RSQ=0.89）, gelatinization temperature range （Tr） （SEP=2.234 ℃, RSQ=0.86）, and cooling resistance （CR） （SEP=0.528, RSQ=0.89）. Gelatinization completion temperature （To）, enthalpy of gelatinization （△H）, cooling loss （CL） and swelling degree （SWD）, were modelled less well with RSQ between 0.63 and 0.84. The present results suggested that the NIRS based method was sufficiently accurate and practical for routine analysis of sweetpotato starch and its noodle quality.  相似文献   

基于仿生超疏水的拉曼光谱综合实验设计北大核心     

高宇坤  尤汀汀  殷鹏刚 《实验技术与管理》2022,(1):191-193

文章以研究生实验课程为例,设计了一种基于仿生超疏水微纳多级结构基底制备及在表面增强拉曼光谱中应用的全新实验课程实施方案,分析了该实验课程在研究生教学中的优势。该实验通过引入前沿科学问题、提出新型分析手段以及结合实际应用等方式,对实验方法、实验步骤进行了改进设计,有利于提高学生的科研兴趣,培养他们的创新思维,锻炼他们的钻研精神。  相似文献   

中国区域产业链创新能力评价体系构建及实证——以激光产业为例     

曹晨  江洪  叶茂  章日辉 《科技管理研究》2023,(5):46-53

从创新资源投入、创新成果产出、产业关联及结构、科技转化能力、创新环境支撑5个维度，筛选并构建包含34个末端指标的评价体系。以中国激光产业2019年指标数据为样本，运用层次分析（AHP）-熵权法模型，对华东、华南、华北、华中、西南、西北、东北七大地区的激光产业链创新能力进行评价。结果表明，中国激光产业链创新能力从区域分布上呈现出东强西弱、南强北弱的局面。其中，华东地区、华南地区的激光产业链创新能力较强；华中地区有较好的政策环境支撑，但在创新资源投入、创新成果产出方面仍有待加强；华北地区整体集中度较低；东北地区、西北地区、西南地区的激光产业链创新能力较弱。  相似文献   

碱金属气室参数测试教学实验平台搭建北大核心     

韩邦成  陆吉玺  张少文  翟跃阳  胡朝晖 《实验技术与管理》2022,(1):56-58

碱金属气室是原子磁强计、原子陀螺仪、原子钟等量子传感器的核心敏感元件,其内部的碱金属原子蒸汽通过与激光、磁场等相互作用,实现对物理量的高精度测量。实验室搭建了针对一类高温、高压碱金属气室的参数测试教学实验平台,该平台通过测量激光吸收光谱,获得气室内部缓冲气体的压强以及碱金属原子蒸汽的原子数密度。该平台使学生能够直接观察到激光与原子的相互作用,有助于学生加深对碱金属气室的理解以及培养学生的实验动手能力,同时也为研究生和本科生的相关课程提供了有力支撑。  相似文献