双轴旋转捷联惯导的误差参数标定方法

针对目前的双轴旋转调制捷联惯导系统误差标定方法参数标定不全、速度较慢的问题,提出一种新的双轴旋转调制捷联惯导系统误差参数标定方法,以实现全参数、快速标定,从而进行误差补偿以有效提升惯导系统导航精度。首先通过研究双轴旋转捷联惯导系统误差补偿的基本原理和系统机械结构,推导了初始时刻内、外轴处于任意角度情况下的陀螺误差方程;而后在对状态方程进行可观测性分析的基础上,设计了标定路径;最后通过滤波获取标定参数结果。该标定方法无需外部基准,仅通过系统自身旋转机构即可快速实现对陀螺误差全参数标定,弥补了之前方法只能标定部分参数的缺点,且有效缩短了标定时间,仿真结果表明,相比之前方法需要几十分钟的标定时间,该方法只要在6min内即可实现陀螺全参数标定,是一种快速有效的标定方案。     

光纤陀螺标定误差对舰船捷联惯导系统的影响

为降低船用光纤陀螺标定误差对捷联惯导系统的影响,有针对性地提高光纤陀螺各标定参数的精度,采用将光纤陀螺标度因数误差、安装误差和零位误差进行分离的方法,推导出光纤陀螺三种标定误差与舰船角速率误差之间的函数关系,将其分别代入舰船捷联惯导系统姿态误差方程进行误差分析.并将舰船摇摆运动下的导航误差与静止下的导航误差进行比较.研究结果表明:光纤陀螺零位误差等效于光纤陀螺漂移,舰船摇摆运动会激励光纤陀螺标度因数误差和安装误差的标定误差对系统的影响.     

激光陀螺捷联惯性导航系统中惯性器件误差补偿技术

为了提高激光捷联惯性导航系统的导航精度，对惯性器件误差进行了原理上的分析和说明，并针对由国内某型激光陀螺构成的惯性测量器件进行了误差分析，在此基础上建立了误差补偿的精确数学模型，提出了一种简易的且具有较高精度的误差模型参数静态标定方法，给出了计算误差模型参数的数学推导过程和解析表达式。分析结果表明，惯导系统误差主要由惯性器件测量误差引起，为了有效补偿惯导系统的系统误差，必须针对具体的惯性器件进行误差补偿，实际测试结果证明，该计算方法精度较高，可以有效提高惯导精度。     

陀螺仪安装误差的测量方法研究

介绍了一种用于测量平台式惯性导航系统陀螺安装误差的陀螺轴扰动技术，该技术无需增加惯导系统的硬件设施，通过对平台框架施加特定的控制力矩，使其按照要求的规律运动，然后采集有关的数据并通过适当的算法即可得到陀螺的安装误差角，理论分析和仿真结果表明，利用该技术可以有效的提高惯导系统的导航精度。     

基于蒙特卡洛方法的惯性元件误差模型分析

为了减小惯性元件误差对捷联惯导系统的影响,将蒙特卡洛方法应用于惯性元件误差模型的分析,并编制了一套在RTLinux下运行的软件.利用轨迹发生器和导航程序,通过对各误差系数的选择、采用拉丁超立方和对偶变数相结合的抽样方法抽样,分析各误差项对导航精度的影响.在此基础上,提取出简化的误差模型,并对简化模型进行评定,选择符合要求的作为适用模型,从而可以利用该模型进行惯性元件的误差补偿以提高捷联惯导系统精度.惯性元件误差模型分析作为导航系统测试平台的一部分,已经应用于工程实践.     

一种抗基座扰动的捷联惯导系统初始对准方法

将自抗扰控制技术应用于捷联惯导系统的初始对准中,提出了一种抗基座扰动的初始对准新方法. 建立了系统的误差模型,深入研究了该对准方法的精度和速度. 计算机仿真和实际系统试验结果均表明,与传统的Kalman滤波精对准方法相比,该方法对扰动具有很好的跟踪作用,是一种应用在捷联惯导系统中的理想对准方案.     

基于光纤陀螺的捷联惯导系统的测试设计

我国煤矿井下瓦斯治理钻孔工程量巨大,目前主要采用人工丈量的方法测量标定开孔方位与角度参数,稳钻时间长、效率低、精度差。针对这一问题,提出基于光纤陀螺的捷联惯导系统开孔参数新方法,该系统采用陀螺与加速度计的捷联惯导系统对钻孔的方位角、倾角进行测量,可以显著提高钻孔方位与角度参数的标定效率与精度,降低管理成本。     

惯导系统初始对准时一种陀螺仪测漂方案

对于长时间运行的惯导系统，陀螺仪的漂移是最主要的误差源，陀螺仪漂移中，一部分是确定性和可预测的，这部分漂移在惯导系统出厂前可以进行标定并补偿，另一部分是随机的，其数学模型有关文献已有详细的讨论。本文要研究平台惯导系统螺仪漂移，在初始对准时一种测定方案及具体数学关系的推导。     

陀螺加速度计在无反转平台离心机上的测试方法研究

提出了一种在不带有反转平台的精密离心机上标定陀螺加速度计误差模型系数的两位置测试方法。在对陀螺加速度计离心机测试环境分析研究的基础上,指出了在不带有反转平台离心机上测试时,地球自转角速度对陀螺加速度计的输出产生周期性误差,影响了测试精度。所提出的测试方案和辨识方法解决了地球自转角速度对陀螺加速度计的输出造成周期性误差这一重要问题。阐述了所提方案的测试原理,并提出分离和精确标定陀螺加速度计误差模型系数的数据处理方法。     

某型捷联惯导系统标定方法研究

该文介绍了某型捷联惯导系统的几种标定方法,根据目前捷联惯导系统标定存在的一些问题,如标定精度分析技术不深入,综合仿真验证技术手段不够等,需要探索新的标定方法来解决。该文先采用对捷联惯性导航核心元件进行系统误差建模,主要研究了传统分立标定方法、系统级标定方法和加速度敏感项标定方法对误差和精度的影响;对船用捷联惯性导航系统的标定精度进行验证时,采用由半实物仿真综合验证技术构建的仿真环境模拟摇摆运动,可实现船用捷联惯导系统的自动化标定,确保系统提供准确导航精度,达到预期研究目标。     

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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