综采面区段煤柱宽度的PSO-SVM预测模型

为准确预测缓倾斜煤层区段煤柱宽度,分析了缓倾斜煤层综采工作面的主要影响因素,选取8个因子,建立了粒子群优化的支持向量机区段煤柱宽度预测模型(Particle Swarm Optimization Support Vector Machine,PSO-SVM),通过缓倾斜煤层的区段煤柱宽度情况统计分析,对粒子群优化的支持向量机模型(PSO-SVM)、网格搜索优化的支持向量机模型(GS-SVM)和遗传算法优化的支持向量机模型(GA-SVM) 3种预测方法的精度进行了对比分析。结果表明:3种方法的预测平均相对误差PSO-SVM为1. 81%,GS-SVM为8. 36%,GA-SVM为3. 78%. PSO-SVM模型有较高的预测精度和较强的普适性,能够相对精确、高效地预测缓倾斜煤层区段煤柱宽度,对缓倾斜煤层综采面区段煤柱宽度选取具有一定指导意义。     

支持向量机在边坡稳定分析预测的应用

目的提出一种基于改进算法的支持向量机模型(PSO-SVM),利用边坡的参数分析预测边坡稳定性.方法利用支持向量机有效解决小样本、高维数、非线性等问题的优势,建立粒子群算法(PSO)优化的支持向量机模型,粒子群算法优化支持向量机参数,模型中边坡几何参数和强度参数:边坡角β、边坡高度H、岩石容重γ、黏聚力c、内摩擦角φ以及孔隙水压力ru作为输入参数,边坡稳定性系数FS和边坡稳定状态S作为输出参数.结果 PSO-SVM模型与网格搜索算法(GS)、遗传算法(GA)优化SVM模型以及人工神经网络ANN模型相比,具有更高的分类精度和更强的预测能力.结论 PSO-SVM模型能够准确地获得边坡的稳定性系数,评价其稳定性,在边坡稳定分析和预测中具有良好的实际应用价值.     

基于粒子群优化的SVR算法与BP网络的比较研究

在回归问题上对比研究了基于粒子群算法优化选参的支持向量回归机模型和采用粒子群算法进行训练的后向传播网络的预测性能.     

基于PCA和PSO-SVM在葡萄酒分类中的应用研究

针对葡萄酒的物理化学成分冗余数据,提出了一种基于主成分分析(PCA)和粒子群优化—支持向量机(PSO-SVM)的模型用于葡萄酒的分类.首先,对葡萄酒的物理化学成分进行主成分分析,提取主要影响因素,减少输入维数,再利用粒子群优算法寻找支持向量机的最佳参数,并用支持向量机完成对训练集样本的学习和测试集样本的预测分类.结果表明,该模型与其他模型相比较,具有较高的准确性,有一定的适用价值.     

基于粗糙集优化支持向量机的泥石流危险度预测模型

为准确预测泥石流危险度,提出了基于粗糙集理论(RS)的粒子群算法(PSO)优化支持向量机(SVM)模型。首先离散化泥石流样本数据形成初始决策表,利用粗糙集理论对10个泥石流危险度影响指标进行属性约简,将约简后的泥石流指标数据归一化处理作为支持向量机的学习样本,通过粒子群算法寻优获得最佳支持向量机模型参数,最终建立基于粗糙集的泥石流危险度预测的优化支持向量机模型。并将构建的RS-PSO-SVM模型用于对测试样本的预测,结果表明：在相同训练样本的条件下,RS-PSO-SVM模型、PSO-SVM模型及RS-PSO-BP模型三者的预测准确率分别为：87.5%,87.5%,75%,说明RS-PSO-SVM模型和PSO-SVM模型具有比RS-PSO-BP模型更高的精度。此外,尽管RS-PSO-SVM模型和PSO-SVM模型具有相同的预测精度,但是由于进行了属性约简,RS-PSO-SVM模型可以有效提高运行效率,降低模型复杂度。     

量子粒子群优化神经网络集成股市预测模型研究

利用量子粒子群优化神经网络集成个体的网络结构和连接权值,对集成个体进行支持向量机回归集成,建立一个新的量子粒子群优化神经网络集成股市预测模型。新模型能有效提高神经网络集成系统的泛化能力,易操作,稳定性好,预测精度高,具有良好的应用前景。     

人工智能在故障诊断中的应用研究

针对神经网络存在的缺点和不足,主要分析神经网络和粗糙集、支持向量机、粒子群、小波相结合使用的方法.粗糙集和神经网络相结合用于故障诊断,可以通过粗糙集的知识约简功能大量消除训练样本中的冗余信息,减少神经网络的输入层节点,简化网络结构,缩短训练时间;基于神经网络和支持向量机的复合故障诊断技术不但可以进一步提高个体模型预测精度,而且可以使故障诊断模型始终处于最优识别状态;粒子群优化神经网络能够加快网络收敛速度,提高训练精度;小波神经网络能够很好地对故障进行分类,具有较高的识别精度.     

基于粒子算法和支持向量机的财务危机预警模型

基于特征集的选择、核函数参数的优化对支持向量机(SVM)模型的预测性能有着重要的影响,提出了一个粒子算法-支持向量机(PSO-SVM)模型.该模型采用PSO对特征集和核函数参数同时进行优化,从而提高SVM模型的预测结果.将所提出的PSO-SVM模型应用到财务危机预警中,取得了较佳的预测结果.     

基于改进支持向量机的空气质量监测预警模型

在使用粒子群和组合预测方法改进传统支持向量机预测精度的基础上,构建了基于空气质量指数的城市空气质量监测预警模型.在参数优化方面,为了提高惩罚参数和核参数的选择精度,利用带收敛因子的粒子群算法,优化了网格搜索交叉验证法的参数筛选流程;在模型改进方面,为综合利用多种预测算法的优势,引入组合预测方式对灰色预测、时间序列预测和PSO-SVM模型的预测结果进行最优线性组合.结果表明:改进后的参数筛选流程和支持向量机的空气质量监测预警模型具有预测数据结构风险低、预测均方误差最小、运算精度高、运算速度快和适用性广等特征.     

基于粒子群算法优化支持向量机的延河流域水沙模拟

对标准粒子群算法进行了简化,并基于简化的算法给出了混沌粒子群算法的优化支持向量机算法.基于延河流域甘谷驿水文站1954—1992年的实测年径流和输沙数据、1992—1995实测月径流和输沙数据,利用该算法和常用的几种粒子群支持向量机算法、误差后向传播神经网络算法预测了1993—1997年期间的年径流量和输沙量、1996年的月径流和输沙量.几种算法的预测结果和实测数据进行了比较,通过相对误差、平均相对误差、均方根误差、一致性指标和有效系数等参数,比较了不同算法的预测效果.结果表明,支持向量机算法模拟效果优于神经网络算法,本文提出的基于改进粒子群算法的支持向量机算法的预测效果更好,可用于流域的径流和输沙量的模拟和预报.     

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

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