马氏链预测模型的代数处理方法

马氏链预测法是通过对事物不同状态的初始概率及状态之间的转移概率的研究,预测事物的未来状态。本文建立了股价预测的马氏链数学模型,用代数的方法处理马氏链的高阶概率转移矩阵和平稳分布。     

在役桥梁承载力模糊可靠性的马尔科夫预测

基于模糊评价和马尔科夫过程，研究了在役桥梁承载力可靠度的时变规律。根据模糊评价理论，确定桥梁承载力状况分布向量，引入马尔科夫过程方法，构造结构状态转移概率矩阵。借鉴时间-空间转换思想，提出一种基于逆阵的改进方法用于计算转移概率矩阵，并给出利用桥梁当前承载力状况分布向量修正转移概率矩阵的方法。针对新建桥梁、在役桥梁以及考虑加固的桥梁分别给出其承载力可靠度分布向量预测公式，并提出承载力预测指标。算例表明，该方法可实现桥梁承载力的可靠度预测。     

马尔可夫链在太湖流域梅雨期预报中的应用

依据1954~1991年太湖流域的入、出梅日期以及梅雨集中期,应用马尔可夫链预报了太湖流域1992年和1993年的梅雨期,并利用其平稳分布分析了梅雨期系统在各状态下的概率.应用结果表明:在太湖流域气候条件稳定的情况下,历史数据越多越精确,预测也就越可靠;以马氏链预测梅雨状态的方法是一种概率预报方法,需通过大量的预测检验才能显示出该方法的准确性和可靠性.     

基于演化博弈的产业集群核心企业和配套企业协同创新分析

企业是产业集群创新的微观主体,但集群企业的创新行为并不独立,受制于其他关联企业。运用演化博弈的方法,对集群内核心企业与配套企业创新行为选择的研究表明:在协同创新过程中,演化结果最终趋向于协同创新和都不创新两种稳定状态,这一过程中创新回报率的大小、创新投入的高低、协同效应的大小及不创新面临的损失等因素变动时会改变趋向于每种均衡状态的概率。     

马尔可夫链模型及其应用研究

马尔可夫链模型是一种将时间序列看作一个随机过程,通过对事物不同状态的初始概率及状态之间的转移概率的研究来预测事物未来状态的数学方法。本文阐述了马尔可夫链模型的原理,并以某技术企业人才职称结构为例进行了预测分析。     

基于PLESN和LESQRN概率预测模型的短期电力负荷预测

针对现有电力负荷预测不能很好反映负荷数据的周期性和趋势性以及残差的波动性特征,提出一种考虑周期性建模的泄露积分型回声状态网络点预测模型和泄露积分型回声状态分位数回归网络概率预测模型组合的短期电力负荷预测方法。首先,为了捕捉负荷的多重特征,定义了周期性和趋势性损失函数,辅助优化点预测模型;然后,为克服残差的波动问题,利用概率预测模型对点预测值与真实值的残差进行建模预测;最后整合同时刻的点预测值与残差预测区间得到概率预测模型结果。实际算例结果表明,与其他模型相比,所提模型不仅有效抑制尖端振荡现象,而且能够生成可靠的概率密度分布。     

基于马尔科夫链的MOOC计算思维学习规模的预测

利用中国大学MOOC平台数据,统计从2012—2018年的计算思维课程修学人数,建立马尔科夫链模型。确定学习规模变化的平稳S、增长G和减少R等3个状态,设定变化概率的计算公式,明确变化概率的值与状态的对应关系,并据此确定一次转移矩阵。根据预测数据的特点,比较估算状态转移概率矩阵的多种求解方法,选择二次规划法求解状态转移概率矩阵。引入最小二乘法的思想,将各个概率非负以及行和为1的条件加入模型中。在Matlab中实现了状态转移概率矩阵的求解过程。依据状态转移概率矩阵预测MOOC计算思维课程的学生规模,进行了模型检验。结果表明,建立的马尔科夫链模型可以预测中国大学MOOC计算思维课程规模的变化趋势,对未来发展规模的预测结果进行了分析。     

马尔柯夫分析在市场研究中的应用

马尔柯夫分析是利用某一变量的现时状态和动向来预计该变量未来的状态及其动向的一种方法。本文仅就马尔柯夫分析在市场研究中的一些应用作一初步的探讨。目的在于促进这一科学方法在商业上的应用。一、状态的初始概率与转移概率马尔柯夫分析是通过对不同状态的初始概率以及状态之间的转移概率的研究,来确定状态变化的趋势,从而达到对未来进行预测的目的。为此,先简单介绍状态的初始概     

基于不确定信息的系统建模与状态预测方法

针对工业过程中广泛存在的信息不确定性、信息传递的时滞特性以及过程本身的非线性和动态特性,研究了基于不确定数据信息的生产过程系统级建模与过程变量的状态预测方法;提出基于小波互信息的信息传递时延估计方法,建立了概率时延符号有向图模型;采用组合预测方法,实现生产过程中关键变量实时状态的准确预测。在空分过程中进行了应用研究,初步结果表明该方法具有良好的预测精度、实用有效,具有应用推广前景。     

基于多层概率集的随机系统预测控制

针对具有Markov跳变特点的一类离散随机系统,研究了输入量概率约束下的状态反馈预测控制问题。采用多层概率集的概念和方法,给出了具有多个不同概率软约束下的预测控制器设计算法,在多步反馈律的控制下,系统状态以指定概率进入不同的椭圆内,保证了系统的稳定性,而且扩大了控制问题的可行范围,改善了系统性能。最后仿真实例证明了所提方法的有效性。     

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