单生反应扩散过程的最优耦合及其应用

论述了单生反应摭用过程最优耦合的存在性，并应用最优耦合对一类单生反应扩散过程的国性进行了研究，给出了一个遍历准则。     

热耦合斯托克斯流问题的有限元分析

针对热耦合的斯托克斯流方程组的解析解给出了其存在性以及正则性的分析. 给出此方程组多解情形下的有限元格式,并且证明了此非线性问题数值解的存在性.研究方程的非奇异解的逼近性质的同时,证明了有限元解的收敛性.在Lp理论下给出了其最优的误差估计.     

具测度初值的非线性抛物方程组的Cauchy问题

研究了一类具强耦合源的退化抛物方程组的Cauchy问题,其中初值为Radon测度。当指标满足一定范围时,克服了方程退化性与强耦合源同时存在带来的困难, 从而得到了解的存在性。还进一步证明了指标的限制范围对解的存在性来说是最优的。     

区域分解算法边界控制近似方法

采用最优控制的方法解决区域分解算法中内交界面上方程解的值的确定问题。将确定内交界面值的问题转化为边界控制问题,为克服控制问题的不适定性引入了正则化方法,证明了正则最优边界的存在性和收敛性,给出了表征最优边界的耦合方程组。     

一类距离下的最优耦合

研究了跳过程在一类距离ρ下的最优耦合，证明在相当弱的条件下，如果存在的保序耦合Ω，则Ω是ρ最优的，并且给了Ωρ的明确表达式，还讨论了离散时间马氏链在该类距离下的最优耦合，结论与连续时间的情形是平等的。     

二维生灭过程的最优耦合

解决了在给定的一些距离这下二维生灭过程的最优耦合问题，给出了这些最优耦合的结构，并对所得结果做了一些比较。     

串调动力制动系统的计算机仿真及参数寻优

串调动力制动闭环系统,是一个多变量互有耦合的非线性系统,其调节器的参数难以用一般工程方法加以确定。利用计算机仿真和寻优可以很方便地获得闭环最优控制系统参数。文中采用的变步长公式、单纯体相对边长算法以及收敛速度缓慢和发散的处理程序,为保证仿真寻优过程的迅速性和准确性提供了有效的方法。     

两个复杂网络的指数同步的最优牵制控制

研究了两个复杂网络指数同步的最优牵制控制问题．基于线性反馈策略， 给出了两个网络达到指数同步 的牵制准则．通过具体例子展示了牵制节点数目和反馈增益的可行组合的计算方法以及最优组合的确定方法， 同 时也分析了耦合强度和网络的稠密程度对最优牵制比的影响． 最后， 给出两个例子验证了该最优控制方法的有 效性．     

光面爆破径向不耦合系数优化研究

隧道爆破施工时,径向不耦合系数是一个重要的参数,它直接影响爆破质量的好坏。为获得最优径向不耦合系数,基于武汉地铁二号线工程实例,运用ANSYS数值分析软件,建立了径向不耦合系数K为1.0、1.4、2.1时的三维模型。通过比较分析关键部位的应力值大小及分布规律,验证了经典爆破理论,得出了最优径向不耦合系数为1.4~2.1。     

双转子电动机动力耦合系统中发动机的控制方法

为了解决双转子电动机动力耦合系统内发动机的控制问题,基于双转子电动机动力耦合系统的结构与原理,分析了双转子电动机动力耦合系统的工作模式以及各工作模式之间相互切换的条件,并据此提出了发动机最优工作点控制的思路和方法.借助高次幂数据拟合方法与最速下降算法,确定了某型发动机的最优工作点,采用模糊控制方法在Simulink环境内建立了发动机最优工作点控制器的仿真模型.仿真结果表明:发动机最优工作点控制方法能够对发动机转矩、转速进行有效调节,能最大限度降低发动机燃油消耗率;在混合动力驱动低速状态下发动机最优工作点控制方法的寻优时间对系统稳定性有明显影响.     

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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