多卫星遥感数据的信息融合:理论、方法与实践

首先介绍了信息融合技术的有关内容,进而对多卫星遥感数据融合的研究历史及现状进行了简要的综述。在此基础上,以地质应用为目标,探讨了多卫星数据融合的小波变换方法,研究了不同长度的小波基对融合结果的影响,提出了改进的小波融合模型（ＣＭＷＤ）。同时,对比评价了基于小波变换ＣＭＷＤ、ＩＨＳ变换、ＰＣＡ 分析的融合结果在提高空间分辨率、保持原始图象光谱信息的优劣。最后,提出了基于ＭｕｌｔｉＡｇｅｎｔ思想的多卫星遥感信息融合系统框架构想。     

小波变换在遥感图像处理中的应用综述

给出了小波变换的基本性质;综述了小波变换在遥感图像处理中的主要应用,特别是在图像数据压缩、纹理和边缘分析、图像插值处理和多卫星数据融合等方面的作用。从而认为小波理论在遥感图像处理领域有着广泛的应用前景。     

遥感图像双正交小波的数据融合模式研究

鉴于小波变换分析方法在图像处理与图像融合中具有广阔的应用前景，为了获得更好的图像融合效果，首先介绍了图像数据小波分解与重构的基本方法，然后从理论上阐述了具有广义线性相位的双正交小波基的优点，最后通过小波变换与HIS变换的有机结合实现了图像融合。融合后的影像不仅仍然保持了地物的光谱信息，而且保留了高空间分辨率全色波段影像细节清晰的特点。实验结果表明，基于双正交小波变换的多分辨率遥感图像数据融合技术是提高卫星遥感影像解像力的一个重要手段。     

一种基于小波变换的图象融合算法

基于多分辨率小波变换的融合算法近年来得到了广泛的应用。为了充分利用各种遥感图象的信息中,针对“资源一号”卫星图象和SPOT全色波图象,提出了一种新的基于区域能量特征的小波变换复原-增强融合算法。通过同IHS、PCA和HPF几种传统融合方法的比较和结果评价,证明该方法在提高“资源一号”卫星图象空间分辨率的同时,还较好地保留了多光谱图象的光谱信息,并且有效地克服了“资源一号”卫星图象模糊的特点。     

基于双树复小波的遥感图像融合

介绍了DTCWT(双树复小波变换)的基本原理,与传统小波变换相比,DTCWT具有良好的平移不变性和方向选择性,能够提高小波分解和重构的精度,更好地保持边缘、纹理等细节.在传统小波图像融合的基础上,提出了三种基于DTCWT的遥感图像融合算法:基于IHS变换和DTCWT融合法、模值加权融合法和模值局部方差融合法.对"北京一号"小卫星数据进行融合实验,结果表明,三种融合算法不仅有效地增强了融合图像的空间细节表现能力,而且很好地保留了多光谱图像的光谱信息.     

于试验分析确立融合模型的 IHS-小波变换融合方法

在多光谱和全色影像分辨率相差较大情况下,IHS遥感影像融合方法会因光谱分配问题导致一定的光谱扭曲;而小波变换方法在变换域具有良好的分频特性,且融合规则和算子对融合效果作用明显。将IHS和小波变换结合,通过试验分析发现小波分解得到的低频部分与光谱信息关系密切、高频部分与空间信息关系密切。在试验分析的基础上分别给出低频、高频部分的融合规则和算子,应用于BJ-1卫星数据的自身融合验证表明,在保持空间清晰度的同时能够明显地降低光谱扭曲程度,较好解决了其多光谱和全色影像分辨率相差较大对数据融合的影响,相比传统的IHS方法有效降低了光谱扭曲。
     

基于小波包变换的图像多尺度数据融合

在二维小波变换的基础上,给出了图像的二维小波包变换的分析方法,并对已有的几种基于小波和小波包变换的图像融合算法进行了重新组合和改进,提出了一种基于小波包变换的多尺度数据融合方法,给出了一个融合实例。通过对实验的观察和分析,结果表明该算法具有较好的融合效果。     

Pléiades卫星影像融合方法与质量评价

Pléiades星座是法国国家空间中心近年发射的极高空间分辨率卫星,定位精度高、刈幅宽,可实现全球任意一点的每天重访。利用主成分分析、Pansharping、小波IHS变换、小波主成分、小波单波段变换、高通滤波以及Ehlers共7种数据融合方法,对试验区的Pléiades全色和多光谱数据进行融合处理;从融合前后影像的信息熵、标准差、平均梯度、偏差指数、光谱相关系数和通用图像质量评价指数等方面对不同方法的融合效果进行了评价。结果表明:小波主成分和Pansharping方法都可以取得非常好的融合效果。     

基于光谱角和光谱距离评价指标的遥感影像融合方法比较研究——以QuickBird数据为例

遥感数据融合是一种得到具有较高空间分辨率和光谱分辨率数据的有效方法,而如何保持地物光谱特性是遥感数据融合的关键问题。QuickBird卫星数据是高空间分辨率遥感数据的典型代表,探讨QuickBird数据的融合方法对于促进该数据的广泛应用具有重要意义,同时也能为其他高分辨率数据的处理提供借鉴。以QuickBird高分辨遥感数据为例,比较研究了目前针对高分辨率遥感数据常用的高通滤波、小波变换、Gram\|Schmidt和Pan\|sharpening 4种融合方法,以反映光谱曲线变化程度的光谱角和光谱距离为指标,评价了4种融合方法对多光谱影像地物光谱信息的保持能力。结果表明:小波变换在显著提高空间分辨率的同时最大程度地保持了原始多光谱影像的光谱信息,是4种方法中最适合QuickBird遥感数据的融合方法。     

基于小波理论的多分辨率多传感器数据融合

小波变换的多尺度特点非常适合多尺度信号的处理,可以用于多分辨率多传感器数据融合,本文研究了不波变换的特征,提出基于小波包变换的多分辨率多传感器的数据融合算法,算法不需要把小波系数当成白噪声处理,并一能够有效地降低向量和矩阵维数,减少运算,有较好的滤波性能,同时采用双正交小波包变换,这可以克服基于正交小波包变换的多尺度滤波中正交小波因不具有线性相而产生恢复失真的缺陷,进一步提高滤波性能。     

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