飞机驾驶舱噪声环境下的飞行员语音端点检测

为在飞行驾驶舱噪声环境下准确判定飞行员语音端点,提出一种鲁棒语音端点检测方法。使用最优改进对数谱幅度估计语音增强算法进行初步语音降噪,通过Teager能量算子进一步滤除残余噪声,并将降噪后语音短时能量与子带谱熵的比值作为双门限判决参数,检测飞行员语音起止点。实验结果表明,与基于能量参数或频谱熵参数的语音端点检测方法相比,该方法能有效提高检测正确率。     

基于子带能熵比的语音端点检测算法

准确地识别语音端点是语音识别过程中的一个重要步骤。在低信噪比环境下,为更好地增强语音和噪声的区分度,提高语音端点检测系统的准确率,在分析了常规子带谱熵端点检测算法的基础上结合子带能量,提出了一种基于子带能熵比的语音端点检测算法。该算法将子带能量和子带谱熵的比值作为端点检测的重要参数,以此设定阈值进行语音端点的检测。实验表明,该算法快速高效,具有较高的鲁棒性,在较低的信噪比环境下能准确地进行语音端点检测。     

低信噪比环境下子带能熵比端点检测算法

语音端点检测是将采集到的语音信号从复杂的噪声背景中提取出来，确定每段语音的开始和结束，是后续处理的基础。对于语音端点检测在低信噪比的复杂噪声环境下准确率低的问题，提出了一种多窗谱估计减噪和子带能熵比法结合的语音端点检测算法。该算法通过改进多窗谱谱减法对语音信号进行减噪，在分析了常规谱熵端点检测算法的基础上结合对数能量，以改进的子带能熵比作为阈值进行端点检测。实验表明，该算法在不同环境的低信噪环境下，准确率高，具有较高的鲁棒性。     

短时TEO能量在带噪语音端点检测中的应用

语音端点检测是语音识别系统的一个重要组成部分,特别是在噪声环境下,其准确性直接影响到语音识别系统的计算复杂度和识别性能。提出了一种在噪声环境下基于短时TEO能量的语音信号端点检测方法,采用了双门限-三态转换判决机制以保证算法在噪声环境下的端点检测准确性和对信号绝对幅度变化的稳健性。实验结果表明,与传统的短时能量法和谱熵法相比,该算法在低信噪比情况下具有更好的端点检测能力,显示了算法的优越性。     

一种改进的语音端点检测方法

为了提高低信噪比下语音端点检测的性能,提出了一种改进形式的谱减法与改进的功率谱熵法相结合的语音端点检测算法。该算法首先利用改进的谱减法有效地降低背景噪声,然后再用短时平均幅度加权的方法改进功率谱熵,从而判定去噪后语音的端点位置。仿真结果表明,该方法具有良好的检测能力,在低信噪比环境下能比较准确地检测到语音的端点。     

一种基于自适应谱熵的端点检测改进方法

在低信噪比的环境下,为增强与噪声的区分度,提出了一种适应于低信噪比环境的语音端点检测方法.通过改进语音端点检测的特征参数,更好地区分语音信号与噪声信号,提高在低信噪比环境下的端点检测正确率.基于子带谱熵,引入正值常量对基本谱熵参数进行算法改进,得到改良的负谱熵特征,并结合自适应子带选择方法,得到一种新颖的特征参数--自适应子带常量负谱熵.特征在低信噪比的情况下有较强的抗噪能力,并能够准确地检测出语音端点.实验结果表明,不仅快速有效,具有较强的鲁棒性,而且适合低信噪比的语音端点检测.     

改进的语音端点检测技术

为了提高低信噪比下语音端点检测的性能,提出了一种改进的基于谱减法和自适应子带谱熵的语音端点检测方法。该方法先利用谱减法对带噪语音消除加性噪声,及时更新背景噪声估计,再对增强后的语音信号利用改进的自适应子带谱熵进行端点检测。实验结果表明,该方法具有良好的检测性能,相对传统方法提高了端点检测的准确率,在低信噪比环境下仍能比较准确地检测到语音的端点。     

基于动态特性的D-LTSV语音端点检测方法

端点检测是语音信号处理的一个关键环节。为提高语音在低性噪比以及非平稳噪声环境下的端点检测性能,在长时信号变化特征(LTSV)的基础上提出一种新的D-LTSV语音端点检测方法。采用Bartlett-Welch方法估计语音谱,分析语音谱在长时域上的熵,利用倒谱的动态特性分析方法提取连续帧熵值的动态变化特征。实验结果表明,D-LTSV综合考虑了语音的非平稳性和帧间非平稳性的动态变化情况,具有比LTSV更好的分辨能力,特别是在低性噪比和非平稳噪声的环境下,D-LTSV的分辨能力提升了50.77%,能够准确地进行端点检测,具有更强的鲁棒性。     

一种新的基于信息熵的带噪语音端点检测方法

在自动语音识别和变速率语音编码技术中,语音端点检测是前端处理的一个重要环节.而在实际的噪声环境下,一些传统的端点检测方法已不适用.该文提出了一种新的基于信息熵的语音端点检测方法,该方法通过对语音信号的短时功率谱进行谱分析,由此构造熵函数作为端点检测的特征参数.实验结果表明,该方法在噪声环境下性能优于传统的基于能量的端点检测方法.而且相对于基于频谱谱熵的算法,在低信噪比（SNR〈0dB）情况下,该文方法有更好的鲁棒性,可使平均检测精确度进一步提高约5%.     

基于自适应子带功率谱熵的语音端点检测算法

在语音处理中,鲁棒性端点检测是语音处理最重要的领域之一,首先提出了一种子带功率谱熵(SPSE)的特征参数,然后,该参数结合Wuetal提出的自适应子带方法(ABS);发现了一种新颖的鲁棒特征参数-自适应子带谱熵(ASPSE),它能成功地在不同的背景噪声下检测语音端点。实验结果表明,在不同的噪声环境和信噪比下,ASPSE参数非常有效,而且该算法优于其它算法。     

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     

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.     

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。