基于BP神经网络的海洋声学仪器信号识别方法

分析了几种常用海洋声学仪器信号的基本特征,提出一种基于误差反向传播(back propagation,BP)神经网络,以实现对信号特征参数进行分类、识别的方法.该方法采用短时傅里叶变换提取信号特征参数,运用Levenberg-Marquardt算法训练BP神经网络.以实测海洋声学仪器信号的特征参数进行训练后,采用实测和仿真样本对BP神经网络的识别能力进行测试.实验结果表明,BP神经网络能够有效地区分不同海洋声学仪器的信号,识别准确率达到95%以上,且虚警率低于5%.该研究成果可用于识别海域中不同海洋声学仪器,检测海洋中声学仪器的工作状态.该识别方法对于其他海洋声信号的识别研究也有一定的参考价值.     

基于改进GA算法优化RBF网络的航空发动机叶片损伤图像识别

通过对航空发动机叶片损伤图像进行识别,可以快速准确的发现叶片损伤状况,有利于对故障进行及时有效的预测。本文对损伤图像进行分割,提取损伤图像特征参数,采用改进GA算法优化RBF网络参数的方法建立航空发动机叶片损伤图像识别模型,对损伤图像特征参数样本进行仿真实验,识别正确率为93.33%,同时与单一RBF网络模型识别结果进行对比分析,结果表明该方法更加优越有效。     

基于特征参数的语音情感识别

语音情感识别是人工智能领域的研究热点.对不同的特征参数提取直接影响了语音情感识别的效果.通过提取基频、共振峰和Mel频率倒谱系数三个能够充分反映语音情感的特征,采取支持向量机的方法对样本进行分类学习.实验结果表明这三种特征参数能够有效识别语音情感.     

基于深度学习和稀疏表示的害虫识别算法

对农作物害虫种类和数量进行有效的预测是农作物病虫害防治的关键环节,因此基于捕获害虫的样本图片对农作物害虫进行准确的种类识别可以为病虫害的防治提供一定的先验知识.由于农作物害虫种类和形态的多样性及不同种类害虫颜色和纹理的相似性,增加了害虫分类识别的难度.为提高害虫图像识别的准确率,提出了一种基于深度学习和稀疏表示相融合的方法来进行害虫的检测分类识别,进而实现对农作物病虫害的有效防治.该算法首先利用高效的深度学习caffe框架来构建提取害虫特征的网络模型,然后利用该网络模型来提取训练害虫样本的特征向量,从而建立不同种类害虫的超完备字典,最后采用稀疏表示算法来对测试样本进行分类识别.实验部分对10种常见害虫进行了检测识别,实验结果表明新提出的算法有很好的检测分类效果.     

基于改进GFCC特征参数的广播音频语种识别

针对广播音频语种识别中与语种识别无关的特征对识别结果产生影响的问题, 提出一种基于伽马频率倒谱系数的改进特征参数的语种识别方法. 通过提取每帧信号的能量谱包络, 去除部分与说话人相关的特征, 采用Gammatone滤波器组滤波, 经离散余弦变换后再进行倒谱提升, 得到改进的伽马频率倒谱系数特征参数. 将广播音频信号提取特征参数输入隐Markov模型中进行训练测试, 得到的语种识别结果表明, 该方法有效提升了广播音频语种识别的准确率, 优于目前使用的伽马频率倒谱系数特征及其衍生方法.     

基于SBN模型的Internet应用协议识别方法

针对网络流量协议标注比较困难的问题,提出一种基于贝叶斯网络的半监督学习模型,以提高Inter-net协议的识别精度.该模型首先使用少量的标注样本训练贝叶斯网络分类模型,并对未标注样本进行初始分类,然后从未标注样本中挑选分类损失最小的样本加入到训练集中并重复训练分类模型,经过多次循环训练出最终的分类器.该模型可以使用未标注样本和标注样本共同训练分类模型,非常适合于标注比较困难的Internet应用协议的识别.实验结果表明：在标注样本较少的情况下,该模型的识别精度和稳定性均优于朴素贝叶斯模型和贝叶斯网络模型,对于提高Internet协议的识别精度是有效的.     

概率神经网络在文本无关说话人识别中的应用

采用基于听觉特性的Mel频率倒谱系数作为说话人识别特征参数,对概率神经网络进行了描述,并使用该网络进行了文本无关说话人识别研究.实验表明,对20名说话人,用7秒语音训练,3秒语音识别时,该方法可达到96.7%的正确识别率.     

基于一种新特征参数的说话人识别

针对传统的特征参数Mel频域倒谱系数MFCC难以满足语音信号的非平稳性问题,提出一种基于小波分析的新特征参数FPBW的提取方法.为了提高训练速度,采用正交高斯混和模型,将正交变换改到最大期望EM算法之前进行,从而减少训练时间.实验结果表明,新的特征参数FPBW优于特征参数MFCC,并且采用正交高斯混合模型进一步提高了识别性能和训练速度.     

SAR-LAM:面向小样本SAR目标识别的轻量化适应策略

针对小样本学习中跨域迁移导致模型性能下降的问题,提出一种面向小样本SAR目标识别的轻量化适应策略(SAR-LAM)。该方法通过知识蒸馏预训练一个具有泛化性能的通用编码器,向其中嵌入一个只在少量目标域样本上进行训练的适应模块,而后将提取的特征映射到一个分辨性更高的空间内,最终以原型网络为基线对查询集样本进行分类。该适应策略以增加少量学习参数为代价,克服了数据分布差异导致模型迁移受限的困难,增强了模型在目标域提取特征的能力,在小样本条件下将SAR目标识别的准确率提升了至少1.93个百分点,较其他方法展现出一定的优越性。     

基于Gabor特征和协同神经网络的车牌识别方法

研究了车牌字符识别问题,针对车牌识别系统易受天气及光照变化影响的实际应用,将Gabor特征和协同神经网络应用在车牌字符识别中,提高了识别率.首先对车牌字符进行二值化和切分,然后利用Gabor滤波器提取车牌字符的特征参数;再利用协同模式训练特征参数,进而得出训练样本;最后根据协同神经网络进一步识别车牌字符.通过大量仿真实验表明,该方法在不同场景、光照条件下,与传统方法相比,识别率有了较大改进,该方法在车牌识别领域有较强的实用性.     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with