光纤陀螺惯性测量单元数据采集系统设计

为了满足捷联惯性导航系统对惯性测量单元低成本、小体积、高速率等要求,提出了一种捷联式惯性测量单元的设计与实现方法。该系统以开环光纤陀螺和硅微加速度计作为惯性敏感元件,采用高速DSP作为中央处理器实现数据采集、处理及输出,重点介绍了系统的数据采集模块、处理模块、通讯模块等硬件电路及相应软件的设计。系统中选取了高性能的集成电路芯片,在DSP的基础上进行了简易可靠的接口电路设计和在线误差校正,试验结果表明该信号采集系统能满足捷联惯性导航系统的技术要求。     

船用捷联式惯性导航仿真系统设计及研究

针对船用捷联式惯性导航系统长时间工作后,精度明显下降,不能满足导航需求的问题,设计了一种模块化的船用捷联式惯性导航仿真系统,并进行了仿真研究。将船用捷联惯导设计为四个模块,分别为轨迹仿真模块、惯性器件仿真模块、导航解算模块和误差分析模块。利用建立的模型,仿真分析捷联式惯性导航系统姿态角、速度和位置误差的主要特性,研究天向速度的发散对东向和北向速度误差的影响,探究初始对准误差对导航精度的影响。结果表明,仿真系统可以很好的模拟舰船捷联式惯性导航系统的初始对准和导航过程;天向速度的发散和初始对准的精度都会直接影响导航精度。因此,在舰船长时间航行时,必须提高初始对准精度且引入阻尼系统,以减小船用捷联式惯性导航系统的导航误差。     

船用捷联式惯性导航仿真系统设计

针对船用捷联式惯性导航系统长时间工作后,精度明显下降,不能满足导航需求的问题,设计了一种模块化的船用捷联式惯性导航仿真系统;并进行了仿真研究。将船用捷联惯导设计为四个模块,分别为轨迹仿真模块、惯性器件仿真模块、导航解算模块和误差分析模块。利用建立的模型,仿真分析捷联式惯性导航系统姿态角、速度和位置误差的主要特性,研究天向速度的发散对东向和北向速度误差的影响,探究初始对准误差对导航精度的影响。结果表明,仿真系统可以很好地模拟舰船捷联式惯性导航系统的初始对准和导航过程;天向速度的发散和初始对准的精度都会直接影响导航精度。因此,在舰船长时间航行时,必须提高初始对准精度且引入阻尼系统,以减小船用捷联式惯性导航系统的导航误差。     

微小型惯性测量组合的标定方法研究

在捷联惯性航向姿态测量系统中,微惯性器件是核心部分,陀螺和加速度计的精度直接影响整个系统的性能.本文设计了微惯性测量单元MIMU的结构,建立了数学模型,采用翻滚法和转台法,分别标定加速度计和陀螺的零位偏差、标度因子及安装角误差.     

基于信息层的捷联惯导信号反演技术

针对惯性导航的器件价格昂贵且建模复杂,以及全球导航卫星系统(global navigation satellite system,GNSS)/惯性定向定位导航系统(inertial navigation system,INS)组合导航对信息传递速度较慢的问题,提出了一种基于信息层的捷联惯导信号反演技术.在整理归纳了惯性导航中常用坐标系的定义后,首先给出了根据已知的原始目标的欧拉角进行姿态矩阵的计算;然后重点讨论了如何根据已知位置、速度和姿态矩阵,反演其比力、角速度;最后叠加误差得到仿真条件下的惯导器件测量值.仿真结果表明:从一段运动轨迹中反演得到的比力和角速度,是以信息帧格式模拟输出惯导器件测量值,再应用惯导方程进行验证,得到的结果误差符合惯导系统误差允许范围.     

四阶龙格库塔法在激光陀螺捷联惯性导航系统中的应用

在激光捷联惯性导航系统中,应用四阶龙格库塔法求解载体速度增量,有效地解决了载体转动过程中三轴陀螺角速度变化对速度的影响,通过与三轴加速度计实测的X,Y,Z方向的加速度叠加,大大减少了导航中速度的累积误差,保证了捷联惯性导航系统在地理坐标系东北天中实时测量载体的三轴运动速度,以及载体航向、横滚、俯仰的快速实时输出,提高了纯惯性导航系统姿态精度和定位精度.动静态寻北、导航实验及捆绑载体测量其姿态跟踪性能的测试结果表明,寻北精度CEP小于0.5密位,横滚、俯仰精度误差小于0.3密位,里程计组合导航精度误差小于1‰.     

基于OpenGL的捷联式惯性导航系统三维路径重建技术研究

简述了使用OpenGL技术设计实现捷联式惯性导航系统三维路径重建的过程。对捷联式惯性导航系统进行轨迹数据的加工整理、路径曲线的三维观察及重建、三维路径的工程图表示和路径曲线分段的半径标识。利用CAD软件进行绘图设计和造型分析的结果表明,采用自主式的捷联式惯性导航系统进行路径重建在检测运动参数方面的重要性。     

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。     

基于MATLAB组件GUI的捷联惯性导航系统教学仿真平台设计

针对捷联惯性导航系统成本高、实践条件复杂的情况,为满足导航专业学生实验课程的需求,利用matlab平台下的GUI组件搭建了捷联惯性导航系统教学仿真平台。该平台通过设置载体运动状态,可以模拟载体惯性器件陀螺仪和加速度计的参数,并进行导航结算,给出位置、速度、姿态等导航结果,最终实现各项信息的图文输出。学生可利用该平台模拟惯性导航系统,将理论知识与实践操作相结合。该平台为相关专业学生对捷联导航系统学习提供有效的途径。     

光纤陀螺捷联惯组姿态算法改进研究

采用陀螺角增量信号来进行设计的传统的捷联姿态算法,应用于输出为角速率的干涉型光纤陀螺构成的捷联姿态系统时,不仅在精度上存在局限,而且还由于通过角速率提取角增量而带来更大误差。为此,提出了一种仅以角速率为输入信号,双回路迭代新算法,并在典型圆锥运动条件下以算法漂移误差最小为优化准则,推导了新算法相应的圆锥补偿系数方程和算法误差表达式。仿真结果表明,所设计的改进新算法相比于同角速率抽样值的常规角速率输入的圆锥补偿算法精度显著提高。新算法的提出为光纤陀螺捷联惯组圆锥误差补偿提供了一种新的思路。     

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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