多摄像机协同的室内实时地图构建方法

针对多摄像机时空信息提取精度低、融合效果差、与GIS集成困难的问题,提出了一种多摄像机构建室内实时地图的新方法.以高精度室内地图为基础,结合室内地理场景中的先验知识,计算各摄像机与室内地理空间的高精度单应矩阵;通过深度学习的方法,分别构建了人员头部前视和后视目标检测模型,实现了人员头部的高精度检测,并映射至地理空间;对...     

高大空间消防电气设计——山西省图书馆火灾报警系统设计实例简介

文章介绍了山西省图书馆火灾报警系统设计实例。针对建筑物中庭的高大空间,采用双波段火灾探测器,有效探测火灾火焰和火灾烟气;采用微机信息处理系统构成了集火灾识别、火灾定位、现场监控、消防炮扑救于一体的火灾安全监控及联动灭火系统;同时辅以搭建于闭路电视监控系统平台上的视频火灾安全监控系统,满足了图书馆建筑对于早期火灾报警的特殊需要。     

浅谈摄像测量学

摄像测量学(Videometrics)是由传统的摄影测量学、光学测量与现代时尚的计算机视觉和数字图像处理分析等多学科交叉融合形成的。其主要研究如何利用摄像机、照相机等对动态、静态目标进行拍摄得到的序列或单帧数字图像。结合目标三维信息的     

应用新技术监测重点倾废区的环境变化

到1997年5月,我国各海区正在使用的试验倾废区、临时倾废区已经达到54个。1985年～1986年和1991年～1992年,有关部门曾2次组织对倾废区进行调查,调查结果显示,疏浚物是我国海洋倾废的主要废弃物之一,疏浚物的倾倒已经对海洋环境造成了一定程度的危害。 对废弃物倾倒后产生的有害环境影响进行专     

数字航摄像机（DMC）生产大比例尺3D产品的精度分析

随着数字航摄像机(DMC)技术和航空摄影测量技术的迅速发展,利用数字航摄像机(DMC)获取航空摄影测量数字影像,实现航空摄影测量工程项目,摄影投入资金较少、影像分辨率高、信息逼真丰富、测绘生产周期短、成果资料的现势性更强。该项技术近几年来在许多领域内得到了广泛使用,其成果的数学基础、地理精度、现势性、要素的属性精度及拓扑关系等同于常规航空摄影测量的技术要求和质量标准,数学精度(包括平面精度和高程精度)能否满足规范要求呢?本文结合作者参加对广东某市利用数字航摄像机(DMC)进行航测数字化测图生产全过程的监理以及对最终成果的检验,探讨数码航摄像机(DMC)摄影测量生产大比例尺3D产品的数学精度。     

多视几何中外参数与航测外方位元素的相互转化

多视几何与传统摄影测量存在很多相似性,其相关理论与技术发展对传统摄影测量极具借鉴意义,然而如何将多视图几何理论融入传统摄影测量仍是有待解决的问题。针对如何实现多视图几何中相机外参数与摄影测量中相机外方位元素相互转换展开研究,通过详细介绍与分析两者在各自理论系统中的具体含义,推导并给出两者的互相转换公式。实现多视图几何中外参数与摄影测量中外方位元素转换,对于两学科间理论成果的相互补充具有实际意义。     

浅谈呼和浩特市数字摄影测量技术在1∶1000地形图测绘中的应用

本文介绍了利用数码航摄像机进行常规的彩色数码航空摄影,利用Geolord-AT空三软件、JX4G软件与Microstation软件进行全要素地物采集、制作DEM和DOM。     

Concurrent Upward Lightning Flashes from Two Towers

Upward lightning flashes initiated simultane- ously from two towers separated by a distance of 3420 m were analyzed in detail based on high-speed camera images and S-band Doppler radar echo intensity. Both discharges lasted more than 250 ms and were self-initiated from the towers in the form of upward positive leaders with a time difference of less than 4 ms. Abundant recoil leaders oc- curred transiently in the remnant channel sections during the development of the upward lightning. The number of recoil leaders over the lower tower was greater than over the higher tower. When the concurrent upward flashes occurred, the radar echo intensity in the area of the towers was no more than 45 dBZ and the towers were separately located beneath two echo centers with low altitudes of 2-3 kin.     

Event Scenario Analysis for the Design of Rockslide Countermeasures

The Torgiovannetto quarry（Assisi municipality,central Italy） is an example of a site where the natural equilibrium was altered by human activity,causing current slope instability phenomena which threaten two roadways important for the local transportation.The quarry front,having a height of about 140 m,is affected by a 182,000 m3 rockslide developed in intensely fractured limestone and is too large to be stabilized.In 2003 some tension cracks were detected in the vegetated area above the quarry upper sector.From then on,several monitoring campaigns were carried out by means of different instrumentations（topographic total station,extensometers,inclinometers,ground-based interferometric radar,laser scanner and infrared thermal camera）,allowing researchers to accurately define the landslide area and volume.The latter’s major displacements are localized in the eastern sector.The deformational field appears to be related to the seasonal rainfall.The landslide hazard associated with the worst case scenario was evaluated in terms of magnitude,intensity and triggering mechanism.For the definition of the possible runout process the DAN 3D code was employed.The simulation results were used in order to design and construct a retaining embankment.Furthermore,in order to preserve both the safety of the personnelinvolved in its realization and of the roadways users,an early warning system was implemented.The early warning system is based on daily-averaged displacement velocity thresholds.The alarm level is reached if the prediction based on the methods of Saito（1969） and Fukuzono（1985） forecasts an imminent rupture.