用于干涉型光纤陀螺温度漂移辨识的RBF神经网络改进算法

针对干涉型光纤陀螺(IFOG)温度漂移的辨识,推导了径向基神经网络(RBFNN)中隐含层神经元、网络的抗噪声性能和拟合精度三者之间的关系,并在此基础上提出了一种新的径向基函数神经网络辨识学习规则.该方法具有很强的抗噪声性能,网络输出不会被陀螺噪声所污染,同时能动态地确定神经元数,辨识精度高,有效地避免了传统RBF网络学习算法中事先固定网络结构可能存在的盲目性.实验结果表明,该方法能够快速、准确地辨识IFOG的温度漂移.     

干涉式光纤陀螺的建模与仿真

为干涉式光纤陀螺 ( IFOG)系统建立一个完整的模型并对其进行计算机仿真是 IFOG研究过程中十分基础而又重要的工作 .本文根据 IFOG系统的实际结构特点 ,总结出系统的闭环控制为积分控制 ,由此建立了与实际情况最为接近的非线性动态模型和随机模型 ,并采用面向对象仿真技术对系统进行了动态仿真 .在随机仿真时 ,将各种仿真方法进行比较并结合 IFOG系统中随机噪声的特点 ,为 1 /f噪声选择了经频域处理的移动平均法 ( MA) ,为随机游走噪声选择了白噪声一次离散积分法 ,从而使随机仿真信号最大程度地模拟了实际信号     

基于全相位算法的自适应滤波算法

为减小实时信号的自适应处理时间,改善系统性能,在全相位数据空间概念的基础上,提出一种全相位自适应信号处理方法,并通过仿真对该算法在不同原始信号、不同噪声干扰的情况下进行了性能分析．在对该算法和经典的自适应算法在不同原始信号、不同噪声干扰的情况下进行了性能对比之后,提出了该算法的改进方案来改进输入信噪比小于0时的性能．结果表明,改进方案的输出误差性能达到甚至优于理想状态下的经典自适应算法, 从而验证了该算法及其改进方案的可行性和优越性．     

干涉式光纤陀螺的建模与仿真

根据干涉式光纤陀螺(IFOG)系统的实际结构特点,总结出系统的闭环控制为积分控制,由此建立了与实 际情况最为接近的非线性动态模型和随机模型,并采用面向对象仿真技术对系统进行了动态仿真．在随机仿真时, 将各种仿真方法进行比较,并结合IFOG系统中随机噪声的特点,为1／f噪声选择了经频域处理的移动平均法 (MA),为随机游走噪声选择了白噪声一次离散积分法,从而使随机仿真信号最大程度地模拟了实际信号．     

带随机输出噪声的参考模型自适应系统

讨论了带随机输出噪声的线性时不变对象的参考模型自适应系统。提出一种适用于这种系统的混合自适应控制律,证明该系统所有信号的有界性,计算机仿真验证这种新的混合自适应控制律在存在随机输出噪声的系统中的性能。     

码分多址信道中的迭代译码及干扰消除技术

提出了一种码分多址在高斯白噪声信道中的迭代译码和干扰消除方案,在译码过程中,每个用户 译码器的输出用来生成用户信号的软预测,预测值通过迭代译码和干扰消除得以改进,直到迭代收敛为 止,然后对用户信号进行硬判决输出,最后,给出了模拟结果*结果表明系统性能将得到改善.     

码分多址信道中的迭代译码及干扰消除技术

提出了一种码分多址在高斯白噪声信道中的迭代译码和干扰消除方案，在译码过程中，每个用户译码器的输出用来生成用户信号的软预测，预测值通过迭代译码和干扰消除得以改进，直到迭代收敛为止，然后对用户信号进行硬判决输出，最后，给出了模拟结果。结果表明系统性能将得到改善。     

动态倍频PWM音频输出方案及其在dsPIC芯片上的实现

研究PWM在音频输出上的应用,提出一种可适于一般情况的动态倍频PWM的音频处理方法.该方法克服了传统音频输出中D/A转换器阻抗离散性影响、易受温度等环境干扰、成本和功耗相对较高的缺点,解决了基于PWM的D/A的精度与输出带宽的矛盾,并在Microchip dsPIC30F6014数字信号控制器上实现.该方案可适用于电子噪声严重的环境下进行音频信号传输,是性价比优良的音频信号恢复方案.     

一种高频率分辨率、高频率转换速度的周期方波发生器

提出一种新的方波信号发生器方案，该方案全部由数字电路组成，具有很高的频率分辨率与频率转换速度以及良好的噪声性能。     

一种应用于石英音叉增强型光谱的前置放大电路

针对目前石英增强光声光谱系统存在音叉输出高阻抗和受噪声辐射影响较大的不利因素,本文设计了一种高输入阻抗、高信噪比的前置放大器。该方案使用高输入阻抗运算放大器,减小音叉两级的信号线长度,使用两路信号相减的方式降低噪音和串接的音叉来提高信号,进一步提高信噪比。并在该放大器的基础上,使用压电陶瓷直接激发音叉的方法精确测量了音叉的共振中心频率和Q值。经实验检验,该放大器模块性能稳定、信噪比高且成本低。     

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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