一种改进的立体图像编码算法

为了提高左图像的编码效率,提出了一种新的基于自组织神经网络的立体图像编码算法(SOM VQ DE),SOM-VQ DE算法对右图像采用视差估计补偿技术(DE)编码,对左图像则使用基于自组织特征映射算(SOM)的矢量量化编码来取代传统的JPEG方法,矢量量化与视差估计的残差均使用DCT 霍夫曼进行编码.对立体测试图像Pentagon的实验表明,SOM VQ DE算法能够有效地提高左图像的压缩效率:1)在压缩比均为6.5.1时,SOM VQ DE算法的PsNR较JEPGqG DE算法提高了2.42 dB;2)在PsNR均为30 dB时,SOM VQ DE算法的压缩比改善是JPEG DE算法的1.8倍.     

一种新的自学习特征映射算法研究

为了有效地提高矢量量化(VQ)码书的性能,提出了一种新的自学习特征映射(SLM)算法,并应用到图像VQ中,实验表明,与自组织特征映射(SOM)算法相比,SLM算法具有聚类特性好和峰峰信噪比高等优点,是一种非常有前途的码书设计算法.     

基于GA/VQ的说话人辨认的研究与实现

为了改善在矢量量化说话人识别中,采用模板(码书)表征说话人,模板的质量对识别系统的性能。采用遗传算法改进模板的生成方式,构建了一种GA／VQ说话人辨认系统,给出了一种GA／VQ识别算法,通过遗传操作获得全局优化的说话人模板。实验证明,GA／VQ方法提高了码书的质量,比经典矢量量化识别系统识别率高。     

BAVQ压缩算法应用于SAR原始数据压缩——最佳矢量维数的选择方法

BAVQ压缩算法较BAQ算法有更好的压缩性能,但其应用于实际存在一个主要的制约因素就是算法复杂度。而矢量量化所用的矢量维数是影响算法复杂度的关键因素之一,在分析了VQ量化原理和原始数据相关性特点的基础上,给出了一种有效的最佳矢量维数选择方法。     

语音遥控系统中VQ算法的研究

矢量量化(VQ)是语音识别中广泛采用的数据压缩和编码方法。在实现孤立词识别系统时VQ算法能简单、快速、有效地实现语音命令的实时识别。本文讨论了VQ(vector quantization)算法与语音遥控系统设计,实验结果表明基于VQ的语音识别获得了较好的识别结果。     

基于二级矢量量化的LPC声码器算法

为了有效地减少语音编码的比特数、降低量化误差以及提高解码语音质量,提出了一种二级矢量量化的LPC声码器算法.该算法在模糊聚类与LBG级联的VQ算法的基础上,进一步采用二级矢量量化算法对特征参数矢量进行量化.特征参数为语音的两个特征值:基音周期与增益.第一级码本为矢量码本;第二级码本为误差码本.将该算法应用于LPC声码器中进行仿真实验,结果表明:该算法能有效地降低量化比特数并且减少了量化误差,从而使解码语音质量得到改善.     

一种新的基于自学习神经网络的静止图像编码方案

为了改善JPEG算法的编码性能,提出了一种新的基于自学习特征映射算法(SLM)的静止图像编码方案,基本思想是:1)先用矢量量化(VQ)对图像进行预测,然后进行DCT编码;2)采用新的SLM算法来改善VQ码书性能.实验表明,与JPEG算法相比,该方案具有更高的压缩比和更好的图像质量.     

变比特率均值匹配相关矢量量化图像编码算法

矢量量化(VQ)是一种有效的数据压缩技术。为找出与输入矢量最匹配的码字,传统的穷尽搜索矢量量化编码算法需要计算输入矢量与所有码字之间的失真测度。码书大小和矢量维数越大,穷尽搜索矢量量化编码的计算复杂度就越高。为了降低穷尽搜索矢量量化器的编码复杂度,本文提出了一种用于快速图像编码的均值匹配相关矢量量化器(MMCVQ)。在编码前,首先计算所有码字的均值,然后按照这些均值从小到大对码书进行排序。编码阶段,利用邻近图像块的高度相关性和当前输入矢量的均值共同确定相应的码字搜索范围。实验结果表明,当阈值大小为320时,与传统穷尽搜索矢量量化编码法相比,虽然MMCVQ算法的编码质量下降约0.3～0.4dB,但速度快14倍而且比特率下降0.1～0.2比特像素。     

说话人自动识别技术研究

主要对文本无关的说话人识别技术进行一些探讨。与语音识别不同,说话人识别技术必须提取说话人依赖特点,而语音特征量的选取是利用说话人声音的频谱通过分离傅立叶变换(DCT)获得的。在训练阶段,每一个说话者通过矢量量化产生一个码书(语音数据库)。在认识阶段期间,通过对欧几里德距离代表VQ的计算来减少失真。在一定范围的说话人的语音库中,测试结果表明有很高的识别率,可以达到96%。     

两种最新的运动矢量搜索算法

本文在对块匹配运估值算法进行简要探讨的基础上 ,重点介绍了两种最新的运动估值算法——预测搜索算法 (PSA)和灰色搜索算法 (GPS)。这两种算法利用了运动矢量的时间、空间相关性 ,可以明显的减小搜索范围 ,提高搜索效率 ,并能给出正确的运动矢量     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the