ELM岭回归软测量建模方法

ELM(极限学习机)是一种新型的前馈神经网络,可有效处理函数的回归问题.针对ELM学习算法隐含层输出可能存在的复共线性问题,提出了ELM岭回归(ELMRR)软测量建模方法.该算法利用岭回归方法代替原有的线性回归算法,以误差平方和均值为性能指标,采用粒子群优化算法确定最佳岭参数,克服了传统岭回归算法最佳岭参数难以确定的缺...     

基于分层遗传算法的BP神经网络学习算法

针对BP算法局部搜索能力强,而分层遗传算法全局搜索优势突出的特点,结合二者优势构造了一种分层遗传算法与BP算法相结合的前馈神经网络学习算法．将分层遗传算法引入到前馈神经网络权值和阈值的早期训练中,再用BP算法对前期训练所得性能较优的网络权值、阈值进行二次训练得到最终结果．仿真结果表明,该混合学习算法能够较快地收敛到全局最优解,优于BP算法、分层遗传算法,具有一定的实用价值．     

基于ELM神经网络的FAST节点位移预测研究

针对ELM神经网络隐含层节点数目需要人工设定,容易出现过拟合现象从而导致网络的泛化能力降低的问题,引出了基于误差最小化的ELM神经网络的改进方法 EM_ELM算法,并在理论上论证了EM_ELM算法对于提高ELM神经网络预测精度和泛化能力的可行性.随后将EM_ELM算法应用到FAST节点位移的预测模型中,并且进行了仿真验证.仿真结果表明虽然EM_ELM神经网络在训练时间上有了一定的损失,但是仍能满足实时性的要求,而且它的预测精度和泛化能力都得到提升,证明了改进算法的有效性与可行性,进一步说明了EM_ELM神经网络更适合应用于FAST节点位移预测.     

基于神经元网络的短期电力负荷预测

基于多层感知器可任意精度逼近线性或非线性函数的基本原理，提出一种考虑气候影响因素的多层前馈神经网络的短期负荷预测方法，并给出相应的反向传播算法（BP）的构造过程和训练方法，研究结果表明，基于神经元网络的短期电力负荷预测方法具有精度高的特点，负荷预测结果的相对误差小于3．67％。     

神经网络全局收敛快速算法在非线性建模中的应用

把神经网络当作结构已知的非线性系统,权系数的学习看成非线性系统的参数估计,给出前馈神经网络在线运行投影学习算法,理论上证明算法的全局收敛性,并讨论算法参数的选择范围．通过非线性时变系统的神经网络建模应用的仿真,验证算法的在线运行能力．     

LM算法在神经网络语音识别中的应用

输入语音信号中声音的特征提取和分类识别可以通过多层前馈神经网络大量学习实现,但基于误差反向传播的前馈神经网络(BP神经网络)标准算法收敛速度慢,在训练中效率不高。采用一种快速稳定的Levenberg-Marquardt算法进行语音识别,通过对语音信号的预处理、特征提取和网络结果优化,建立了网络训练样本集,用MATLAB进行了仿真,仿真结果表明,该算法优于传统的BP算法,具有更好的收敛性。     

一种基于扩展Kalman滤波器的神经网络学习算法

为了解决前馈神经网络BP算法在处理非线性对象时，收敛速度慢，易陷入局部极值，需调节参数多等的缺陷，提出将扩展卡尔曼滤波(EKF)算法引入神经网络的学习中．把前馈网络的所有权值、阈值作为EKF算法的状态，网络输出作为EKF的观测．同时为了防止滤波发散，对算法做了改进．仿真结果表明，该算法比BP算法在收敛速度、抗噪能力方面都有明显提高，同时还保证了一定的泛化能力．     

基于BP神经网络的压力传感器非线性校正方法

采用BP多层前馈神经网络及其改进算法对传感器特性进行补偿，有效地改善了BP传统算法收敛慢、容易收敛到局部最小点的缺陷，并编制了训练程序．结果表明，经BP改进算法处理后，传感器性能大幅度改善，网络的收敛速度更快，精度更高．     

切削过程的位置误差补偿控制研究

本文作者运用经典控制论对切削过程的位置误差补偿控制进行了研究．接着，作者对神经网络理论中的标准反向传播算法BP作了改进并提出了IBP算法．基于IBP法，作者构造了一个用于切削过程位置误差补偿控制的多层前馈神经网络控制器，并作了仿真控制试验．研究结果表明：IBP法较标准BP法具有更快的迭代速度和收敛性质；所建的智能控制器虽然结构简单，但在误差补偿控制方面跟经典控制法相似具有一定的控制效果．     

前馈神经网络快速算法及其应用

针对现有前馈神经网络学习算法的缺陷,提出一种前馈神经网络的快速学习算法.该算法是基于无监督学习中的主元分析算法的Oja规则和监督学习中δ规则的.与现有同类算法相比,该算法简化了学习过程,计算量小,有更快的学习收敛速度和更高的收敛精度,较适用于快速学习的系统辨识和其他应用.系统辨识的仿真实例表明了该算法的优良性能.     

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     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~