双频GPS辅助低空航摄大比例尺空三精度分析

针对双频GPS辅助低空摄影测量仍需大量野外控制点布测的问题,通过对飞控系统与相机集成改造,而后对双频GPS有无反馈信息以及不同控制点个数对大比例尺测图空三精度的影响分析,提出一种双频GPS辅助低空摄影测量最优化的解决方案,最大限度减少野外控制点布测数量,从而减少外业工作量。利用轻小型无人机航空遥感系统开展了福建省溪柄镇1∶2 000航空摄影测量试验,并重点分析了双频GPS在相机反馈前后对测区零加入或加入不同个控制点开展双频GPS辅助低空摄影测量对大比例尺测图空三精度的影响。试验表明,在相机反馈后双频GPS辅助大比例尺测图空三时加入6个地面控制点即可满足1∶2 000比例尺测图空三的要求。     

安置元素测图对POS外方位元素的精度需求

基于POS辅助航空摄影测量直接对地目标定位理论,根据误差传播定律建立了物方坐标精度与影像外方位元素精度的关系模型,并从理论上分析了各种基本比例尺地形测图对影像外方位元素的精度需求。通过对摄自不同地区、多种摄影比例尺航摄影像的实验表明,由POS系统获取的影像外方位元素进行安置元素测图完全可以满足各种比例尺、不同地形图测绘的精度要求,但为了满足地物点的高程精度,对影像外方位元素的精度需求较用于平面测图时的至少要高出一倍以上。     

消费级多旋翼无人机1∶500大比例尺测图的应用

消费级多旋翼无人机技术不断成熟,使其用于摄影测量成为现实。利用消费级四旋翼无人机搭载普通相机,开展1∶500大比例尺测图任务,针对消费级无人机和非量测相机的影像采集特点,制定项目实施方案并开展数据生产,实验结果表明：利用消费级无人机进行大比例尺测图的方案可行,测图精度满足规范要求;利用采集影像生成的测区实景三维模型辅助内业成图,能够大幅减少外业调绘工作量。研究表明该方案提高了大比例尺测图的工作效率,减少了项目的总体成本,有很好的经济效益和应用前景。     

雷达干涉测量获取DEM的镶嵌处理方法

主要讨论了填补雷达干涉测量获取DEM(Digital Elevation Model)盲区的方法(镶嵌处理),并设计了具体的数据处理流程,提出了基于空间相关性和数据可靠性的椭球体数据模型,该模型充分考虑了雷达数据在空间各向的精度不等性,并以此模型实现了用1∶10万比例尺地形数字线化图的数据对欧空局(ESA)的星载合成孔径雷达(ERS1/2)处理数据镶嵌的具体应用.     

消费级多旋翼无人机1∶500大比例尺测图的应用

消费级多旋翼无人机技术不断成熟,使其用于摄影测量成为现实。利用消费级四旋翼无人机搭载普通相机,开展1∶500大比例尺测图任务,针对消费级无人机和非量测相机的影像采集特点,制定项目实施方案并开展数据生产,实验结果表明:利用消费级无人机进行大比例尺测图的方案可行,测图精度满足规范要求;利用采集影像生成的测区实景三维模型辅助内业成图,能够大幅减少外业调绘工作量。研究表明该方案提高了大比例尺测图的工作效率,减少了项目的总体成本,有很好的经济效益和应用前景。     

消费级多旋翼无人机1∶500大比例尺测图的应用

消费级多旋翼无人机技术不断成熟，使其用于摄影测量成为现实。利用消费级四旋翼无人机搭载普通相机，开展1∶500大比例尺测图任务，针对消费级无人机和非量测相机的影像采集特点，制定项目实施方案并开展数据生产，实验结果表明：利用消费级无人机进行大比例尺测图的方案可行，测图精度满足规范要求；利用采集影像生成的测区实景三维模型辅助内业成图，能够大幅减少外业调绘工作量。研究表明该方案提高了大比例尺测图的工作效率，减少了项目的总体成本，有很好的经济效益和应用前景。     

基于HJ-1A/B卫星CCD数据的土地宏观监测试验研究

对HJ-1A/B卫星CCD数据质量进行分析,并采用人工解译和计算机自动分类两种方法进行土地利用信息提取试验研究。结果表明,HJ-1A/B卫星CCD数据能够满足制作1∶100 000比例尺数字正射影像图的平面精度要求,可用于不大于1∶100 000比例尺的土地利用宏观遥感监测。
     

数字高程模型坡度误差指标尺度转换分析

针对我国大比例尺DEM数据库尚未建成,但是国家的生产建设又需要1∶5 000DEM所提取的地形因子(如坡度),而目前少有对1∶5 000比例尺DEM转换研究的现状,该研究制定出适合福建全省不同比例尺DEM提取地形因子间互相转换标准。选取福建省典型地貌(山地、丘陵、平原)共7个样区为实验样区,使用python脚本来批量提取7个样区在5种比例尺DEM下的多种地形因子,选取坡度作为研究对象,提出适合中小比例尺DEM向大比例尺DEM转换的3个误差指标:坡度面积、坡度信息熵、坡度鉴别信息,得出1∶10 000、1∶50 000、1∶250 000、1∶500 000DEM所提取坡度因子向1∶5 000转换的定量表达式,制定出中小比例尺DEM提取坡度因子向大比例尺DEM对应因子的转换标准。     

双拼组合宽角相机低空航测实验研究

介绍无人机载双拼组合相机低空航测的实验过程,包括双拼组合相机组成结构、原理以及利用该系统进行大比例尺测图的生产流程,对此过程中出现的误差进行了重点分析,并提出消除误差的方法.理论和实践证明,无人机载双拼相机低空航测可以满足1∶1000测图精度标准,比装备普通单相机工作效率有明显提高.     

IRS-P6卫星在土地利用动态遥感监测中应用的潜力分析

摘要: 为探索新的数据源, 研究了IRS-P6卫星在土地利用动态遥感监测项目中的应用潜力并进行分析, 就IRS-P6 影像在最大成图比例、最小响应图斑面积、地类可解度、地类解译精度等方面进行试验, 通过试验并根据土地利用动态遥感监测项目的技术要求可知, IRS-P6 卫星影像可以用来制作1∶2. 5 万、1∶5 万等中等比例尺的图件, 更新或者辅助更新1∶2. 5 万、1∶5 万的土地利用现状图, 在土地利用动态遥感监测中有一定的应用潜力。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate