机载激光雷达技术在铁路勘察设计中的应用及效益分析

机栽激光雷达技术(LiDAR)是一种全新的遥感技术,因其高精度和高效率,在地形测绘方面得到快速发展,目前国内已有近20套LiDAK系统.本文主要研究LiDAR技术在铁路勘察设计工程中的应用内容、产品与效果,在此基础上与传统的航空摄影测量方法进行了比较,证明LiDAR技术在铁路勘察设计的可行性与优越性.     

用于铁路勘察的机载LiDAR数据生产DEM方法研究

机载LiDAR数据是一种比较好的DEM生产的数据源,尽管生产流程基本成熟,但其中的一些关键技术还不能满足生产需求,需要在行业应用时加以深入研究。针对铁路勘察的具体特点和要求,提出了一种综合使用专业软件和多种航空摄影测量技术手段,满足铁路勘察设计需求的机载LiDAR数据生产DEM方法,并将其运用在生产实践中,大规模生产的结果表明,本流程和方法是可行的。     

基于物联网与BIM技术的铁路勘察设计智能化研究

本文详细介绍了铁路勘察设计平台中物联网与BIM技术的应用方法,提出了铁路勘察设计平台的技术架构与系统结构,基于B/S网络模型完成的系统搭建.在此基础上详细阐述了物联网与BIM技术在施工管理中的应用策略,并给出了相应的图形化展示结果.     

浅谈计算机技术在道路勘察设计中的应用

由于公路、铁路等道路的勘察地形复杂、工作难度大、误差机率高等因素使得道路勘察工作成为了道路建设发展的瓶颈.计算机技术及影像提取测量技术的应用为道路勘察设计带来了新的发展契机.文章就计算机技术在道路勘查设计中的应用进行了探讨.     

机载激光雷达(LiDAR)数据在森林资源调查中的应用综述

LiDAR技术可以直接获取地表地物的三维信息,在森林参数估测方面具有独特的优势,因此,在森林资源调查中有着广泛应用.本文首先介绍了LiDAR系统组成和基本工作原理,然后详细分析了LiDAR技术定量提取树高、林分郁闭度和密度、蓄积量和生物量等森林参数的技术方法与研究进展,并对LiDAR数据在森林及其生态状况监测中的应用前景进行展望.     

DInSAR沉降监测技术在铁路勘察设计中的应用

针对当前铁路勘察设计中面临铁路沿线地表区域历史沉降监测资料缺失、调查困难的问题,该文引入了合成孔径雷达差分干涉测量(DInSAR)技术对铁路勘察设计阶段区域沉降进行监测;结合铁路勘察设计对地表区域沉降需求特点,采用常规差分DInSAR和小基线集(SBAS)技术方案对铁路沿线进行区域沉降监测,并基于不同方案开展了相应实验。实验表明:利用常规差分干涉测量和基于时序的差分干涉测量方法,能够有效地监测到铁路沿线的地表区域沉降范围、沉降量和沉降速率,基于时序的差分干涉测量能够提供更加准确的监测结果,为铁路方案稳定性提供准确的区域沉降资料。     

面向应用的《激光遥感》课程实践设计

《激光遥感》课程是武汉大学遥感信息工程学院为适应遥感技术发展的最新需求,针对本科生设置的一门专业必修课程,为学生传授LiDAR技术的相关知识。本文针对教学大纲和LiDAR技术的特点,根据科研和生产的需要,设计了实践课程,并提出了课程的框架和建设方案。     

勘察设计企业信息系统安全体系建设

随着信息化程度的提高,勘察设计企业对网络和信息技术的应用程度越来越深入,越来越多的数据、流程、知识成果以电子文档的形式储存于各类信息系统中.依据网络安全理论体系和技术,结合某勘察设计企业实际,以管理为基础,以技术为手段,探讨建立实用的勘察设计企业信息系统安全体系.     

集成GIGIS技术与改进LiDAR的建筑测量技术研究

倾斜摄影测量技术因现代测量技术的进步,在众多应用场景中证明了其独特和不可或缺的价值;在GIGIS技术的支持下,研究致力于结合倾斜摄影测量技术与机载LiDAR技术,旨在实现更精确、完整的建筑测量;采用了基于GIGIS的倾斜影像技术,获取了丰富的纹理、色彩特征信息,并利用机载LiDAR技术获取了高精度、低噪声的点云信息,从而优化了LiDAR在建筑测量中的应用;通过对点云特征提取与融合方法的优化,在两个不同区域的测试中,改进后的特征提取准确率分别达到93.56%和92.14%,均明显高于改进前;研究为建筑测量提供了更准确、完整的多源数据特征,为建筑测量技术的进步提供了有价值的方案。     

机载大光斑激光雷达数据估测森林结构参数研究进展

针对LiDAR对森林结构具有较强探测能力,从而能够准确地获取森林的三维结构的优势,该文试图将该技术运用于估测森林结构参数,并介绍了机载大光斑LiDAR系统的工作原理和主要技术规格,系统总结了机载大光斑LiDAR数据估测森林结构参数的研究现状,分析了机载大光斑LiDAR估测森林结构参数的局限性并对其进行了展望。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.