重庆方言语音识别系统的设计与实现

语音识别赋予了计算机能够识别出语音内容的功能,是人机交互技术领域的重要研究内容。随着计算机技术的发展,语音识别已经得到了成熟的发展。但是关于方言的语音识别还有很大的发展空间。中国是一个幅员辽阔、人口众多的国家,因此方言种类繁多,其中有3000多万人交流使用的重庆方言就是其中之一。采集了重庆方言的部分词语的文本文件和对应的语音文件建立语料库,根据重庆方言的发音特点,选取重庆方言的声韵母作为声学建模基元,选取隐马尔可夫模型(Hidden Markov Model, HMM)为声学模型设计了一个基于HMM的重庆方言语音识别系统。在训练过程利用语料库中训练集语料对声学模型进行训练,形成HMM模型库;在识别过程利用语料库中的测试集语料进行识别测试。实验结果表明,该系统能够实现重庆方言的语音识别,并且识别的正确率为100%。     

基于语音结构化模型的数字语音识别

提出一种新的基于语音结构化模型的语音识别方法,并应用于非特定人数字语音识别.每一个数字语音计算倒谱特征之后提取语音中存在的对说话人差异具有不变性的结构化特征——全局声学结构(acoustical universal structure,AUS),并建立结构化模型,识别时提取测试语音的全局声学结构,然后与各数字语音的结构化模型进行匹配.测试了少量语料训练下的识别性能并与传统HMM (hidden Markov model)方法进行比较,结果表明该方法可以取得优于HMM的性能,语音结构化模型可以有效消除说话人之间的差异.     

基于分段模型的连续语音识别

近年来在大词汇连续语音识别的研究取得了长足的进步,隐马尔柯夫模型（HMM）是连续语音识别的核心部分。但是HMM对语音信号的描述不完善,为此人们提出了很多替代模型,其中一类将语音信号描述为长度随机的特征矢量序列,称为随机分段模型（Stochastic Segment Models),简称为分段模型（SM）。该文将首先阐述分段模型的原理,并将分段模型和隐马尔柯夫模型进行比较,其次给出基于分段模型的识别和模型训练算法,最后给出实验结果并进行了讨论。     

基于禁止搜索的离散隐马尔可夫模型优化

隐马尔可夫模型(HMM,Hdden Markov Model)是语音识别中广泛采用的鲁棒性统计方法.本文采用禁止搜索(TS,Tabu Search)算法训练HMM参数,提出了基于禁止搜索的隐马尔可夫模型(TS-HMM)算法.该算法可以使搜索最优模型参数的过程达到全局优化.仿真结果表明与传统的前向-后向算法相比,TS-HMM算法具有更好的性能,且能够达到全局优化.     

基于动态贝叶斯网络的连续语音识别框架及其Token传递模型

近年来,由于动态贝叶斯网络(DBN)相对于传统的隐马尔可夫模型(HMM)更具可解释性、可分解性以及可扩展性,基于DBN的语音识别引起学者们越来越多的关注.但是,目前关于基于DBN的语音识别的研究主要集中在孤立语音识别上,连续语音识别的框架和识别算法还远没有HMM成熟和灵活.为了解决基于DBN的连续语音识别的灵活性和可扩展性,将在基于HMM的连续语音识别中很好地解决了上述问题的Token传递模型加以修改,使之适用于DBN.在该模型基础上,为基于DBN的连续语音识别提出了一个基本框架,并在此框架下提出了一个新的独立于上层语言模型的识别算法.还介绍了作者开发的一套基于该框架的可用于连续语音识别及其他时序系统的工具包DTK.     

基于扩展C型HMM人脸表情识别

隐马尔科夫模型(HMM)能够很好地对时间和空间建模,在对动态的表情序列进行识别时HMM取得了很好的识别效果。但是传统的HMM训练算法基于最大似然准则,在该准则下训练的HMM表情序列模型识别能力有限。针对这一不足,通过增加状态中心参数C对HMM模型进行了扩展,然后在此基础上使用状态空间上隐射算法来建立模型。试验结果表明所建立的扩展C型HMM模型和相应的算法提高了识别能力。     

语音分离与HMM相结合的语音增强方法

针对基于隐马尔科夫（HMM,Hidden Markov Model）的MAP和MMSE两种语音增强算法计算量大且前者不能处理非平稳噪声的问题,借鉴语音分离方法,提出了一种语音分离与HMM相结合的语音增强算法。该算法采用适合处理非平稳噪声的多状态多混合单元HMM,对带噪语音在语音模型和噪声模型下的混合状态进行解码,结合语音分离方法中的最大模型理论进行语音估计,避免了迭代过程和计算量特别大的公式计算,减少了计算复杂度。实验表明,该算法能够有效地去除平稳噪声和非平稳噪声,且感知评价指标PESQ 的得分有明显提高,算法时间也得到有效控制。     

基于词根的中国手语识别方法

迄今为止，手语识别面临的最大问题是如何解决词汇集易扩充的连续识别，提出一种大词汇量连续中国手语识别方法，将词根作为识别基元，由于基元的数目是有限的，因此基于HMM的手语信号的训练和识别变得比较容易处理，可以实现更大词汇量的识别。除此之外，所提方法还有利于实现手势语和手指语的混合识别。从中国手语中共整理现2400多个词根，为每个词根建一个并行的HMM模型，对各数据流的HMM模型进行聚集，确定出手识别的基元。根据这些基元对手妫刻苦骊，并建立了树状搜索网络，使用状态垄点上高斯密度函数聚类、语言模型和N－Best方法提高系统的速度和精度。对5119个手语词做了实验，连续语句的识别率可在90％以上。     

基于HTK的维吾尔语连续数字语音识别

根据HTK工作原理,设计了维吾尔语连续数字识别的训练步骤,进行嵌入式重估训练,建立了基于音素级单位的HMM模型,建立了语言模型,实现了维吾尔语非特定人小词汇量亿以内的数字语音识别.     

基于隐马尔可夫模型的非监督噪声功率谱估计

噪声功率谱估计是语音增强算法的基本组成部分,传统算法大多采用启发式的估计方法,因而不能保证噪声估计值的统计最优。提出了一种基于极大似然的非监督噪声功率谱估计方法,采用隐马尔可夫模型(Hidden Markov model, HMM）在每个子带建立语音和非语音对数功率谱的统计模型,模型包含语音和非语音两个高斯分量,其中非语音高斯分量的均值表示噪声功率谱估计值,根据最大期望（Expectation maximization, EM)算法得到包括噪声均值在内的HMM参数集。针对语音信号可能出现的长时缺失,对HMM引入了一些约束条件,保证了模型的稳定性。实验表明,该方法获得的极大似然噪声估计优于基于启发式的经典方法获得的噪声估计。     

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。     

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.     

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.     

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.