基于方向图的指纹奇异点快速检测方法

准确、快速地检测指纹奇异点(core点和delta点),对指纹分类和指纹匹配等具有重要意义.首先,给出计算指纹图像方向图的算法,然后,在基于方向图的基础上,对传统的基于poincare索引计算公式的指纹奇异点检测算法进行了改进.使用改进算法对PU-JY203U警用活体指纹采集仪采集的指纹(1000枚)进行Matlab仿真.实验结果表明改进后的算法与传统算法相比,在定位奇异点的精确度和速度上都有很大的提高.     

基于加权平均梯度方向场和改进Poincare Index的指纹奇异点检测算法

针对指纹图像具有局部平行性和渐变性以及邻域的脊线方向相关性高的特点，提出了一种基于加权平均梯度的指纹方向场算法。改进了传统的Poincare Index指纹奇异点检测算法。实验证明，在采用加权平均梯度算法获取的方向场上利用改进的Poincare Index算法可实现对低质量指纹图像的奇异点的准确提取。     

一种新的指纹奇异点快速检测方法

作为指纹最重要的全局特征之一,奇异点在基于模型的方向场计算、人工合成指纹、指纹分类、指纹特征匹配等方面发挥了非常重要的作用.在指纹方向场分割的基础上提出了一种称之为方向丰富度的特征,并据此形成了一种新的指纹奇异点快速检测方法.该方法首先将指纹方向场分割为一系列互不重叠的同质区域;然后通过同质区域边缘检测及边缘端点提取实现了奇异点快速定位;最后依据奇异点处方向丰富度特性判断其类型.实验验证了文中算法的有效性.     

一种指纹图像奇异点检测的方法

准确、可靠地检测奇异点(core点和delta点),对指纹分类和指纹匹配具有重要的意义.针对低质量指纹图像奇异点检测中精确定位和可靠性判断的难题,提出了一种检测指纹奇异点的方法.首先,对于一幅指纹图像,在同一分块尺寸下进行多次图像错位分块,并且分别在不同的图像错位分块情况下检测指纹的奇异点,得到区域相对集中的奇异点位置的集合,并计算其质心,以精确地确定奇异点的位置.然后,再在不同的分块尺寸下检测奇异点,并进一步判断上一步所检测到的奇异点的真伪.该方法利用了多次图像错位分块检测的奇异点位置相对集中和各级分块尺寸下检测的奇异点位置相互关联的特性,能够从指纹图像中较精确、可靠地检测出奇异点.在部分典型低质量指纹图像上的实验结果验证了该方法的有效性,对低质量指纹图像具有良好的鲁棒性.     

基于频域分析的指纹奇异点区域提取算法及其DSP实现

本文提出了利用频域分析方法提取指纹奇异点的算法。该算法能在指纹预处理过程中完成奇异点提取,减少了检测奇异点的时间消耗。同时,本文采用TMS320DM642处理器对算法的嵌入式应用进行了研究。实验表明,该算法具有优异的性能。     

基于Gaussian-Hermite矩和改进的Poincare Index的指纹奇异点提取

在指纹分类和匹配中,准确、可靠地提取奇异点十分重要.针对低质量指纹图像奇异点检测中精确定位和可靠性判断这一难题,提出了一种两阶段的奇异点提取算法.首先,针对现有Poincare index方法存在伪点检出较多和抗噪性较弱的问题,通过对其改进实现候选奇异点位置的确定;然后,再通过计算候选奇异点周围圆形邻域的Gaussian-Hermite矩分布属性值来判断其真伪.方法有效结合了奇异点周围邻域的纹线方向和纹线一致性信息,能够从指纹图像中较为准确、可靠地检测出奇异点.在NIST-4和南京大学活体指纹库上的实验结果验证了该方法的有效性和鲁棒性.在从NIST-4中随机抽取的500幅指纹图像上,奇异点的检测准确率为93.05%(Core点准确率为96.93%,Delta点准确率为86.43%).     

改进的结构化指纹分类算法

在深入研究现有指纹分类算法的基础上,提出了一种基于结构的指纹分类算法。利用指纹图像的方向场信息,用Poincare索引值检测出方向场中不连续的点——奇异点,根据奇异点的数目和相互位置关系以及指纹脊线的结构特征确定指纹的基本类型。该算法为匹配算法提供指纹类型信息,可极大地提高算法的匹配速度和匹配精度,具有较好的使用意义。     

基于方向的指纹奇异点提取

准确、可靠地检测指纹奇异点(核心点和三角点)对于指纹的分类和匹配有重要的意义。针对指纹图像奇异点提取中准确判断和精确定位的难题,介绍了一种比较好的奇异点检测算法。根据奇异点的性质,利用Poincare Index方法求出核心点和三角点。根据相关规则,清除虚假奇异点。实验结果证明该方法能够从指纹图像中较精确、可靠地提取出奇异点。用该方法对不同质量的指纹图像进行实验,并与其他方法进行比较,结果表明该方法更加有效、可靠,具有很好的鲁棒性。     

基于方向的指纹奇异点提取

准确、可靠地检测指纹奇异点（核心点和三角点）对于指纹的分类和匹配有重要的意义。针对指纹图像奇异点提取中准确判断和精确定位的难题，介绍了一种比较好的奇异点检测算法。根据奇异点的性质，利用Pcincare Index方法求出核心点和三角点。根据相关规则，清除虚假奇异点。实验结果证明该方法能够从指纹图像中较精确、可靠地提取出奇异点。用该方法对不同质量的指纹图像进行实验，并与其他方法进行比较，结果表明该方法更加有效、可靠．具有很好的鲁棒性。     

基于Gaussian-Hermite矩的指纹奇异点定位

在指纹分类和识别算法中,提取的奇异点(core点和delta点)数目和奇异点的准确位置是非常重要的.介绍了一种基于Gaussian-Hermite矩分布属性的自适应指纹奇异点定位方法,为了准确地确定奇异点,用到了指纹图像在多种尺度下的不同阶Gaussian-Hermite矩分布,并用一种基于主分量分析(principal component analysis,简称PCA)的方法分析指纹图像的Gaussian-Hermite矩分布.实验结果表明,该算法能够准确地确定奇异点位置.     

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。     

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.     

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.     

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.     

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.     

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.     

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。