水下机器人关键区域定位系统的设计与实现

针对水下机器人定位中的淤泥、水流对定位过程的干扰问题,设计并实现了一种引入机器学习的水下机器人高精度定位系统,系统通过信号发射板产生需要的调制信号,利用数据采集模块实现接收处理功能,定位模块作为所提系统的核心模块,通过引入机器学习的思想,实现了水下机器人高精度定位系统的硬件和软件设计,实现定位功能。实验结果表明,所提系统在不同水深环境下,能较好完成水下复杂环境的机器人定位,具有很高的实用性及可靠性。     

水下无人潜航器远程遥控磁传感器设计

基于超/甚低频电磁波的传播特性,提出陆上发射控制指令以实现水下无人潜航器远程遥控的设想;对比分析几种水下接收天线的优缺点,提出小型化高灵敏度感应式磁传感器水下接收遥控信号的方法;为提高小型化磁传感器的灵敏度,采用纳米晶叠片磁芯降低损耗噪声,使用低噪声电子对管降低放大器电压噪声与电流噪声,通过斩波放大技术减小放大模块的1/f噪声,并优化感应线圈的设计以降低热噪声;确定了一组500mm长度磁传感器的设计参数,并仿真该参数下传感器的灵敏度,结果表明该小型化磁传感器的灵敏度满足超/甚低频段水下遥控信号接收的需求.     

基于GPS同步技术的双址声呐信号传输时间测量

为克服传统测量方法信号处理复杂、误差较大以及距离较远时采用无线电遥测同步受电磁干扰较大的缺点,提出一种高精度测量声呐信号传输时间的方法.采用分立声呐接收和声呐发射模块(即双址声呐),利用双GPS精确授时模块实现声呐信号发射和接收同步,接收模块直接接收发射模块的声波信号,通过声呐信号发射和接收的时间差来确定声呐信号的传输时间.系统采用DSP控制声呐信号的接收,利用可编程逻辑器件测定信号的传输时间.实验结果表明,系统工作稳定可靠,测量精度可达5~10μs.     

射频读卡器硬件系统功能简介

系统主要可分为主控模块电路和射频收发电路两部分.主控模块由微控制器及其复位电路,应用系统电路、电源电路及辅助电路组成.主控制器是系统的核心部分,它负责接收用户命令,对发送信号进行编码和对接收信号进行解码,主控制器与应答器的通信过程经由射频收发模块实现.电源电路完成稳压与电压转换功能.射频收发模块有射频发射电路和射频接收电路组成.射频发射电路完成对基带信号的调制发射,射频接收电路完成时载波信号的解调接收.     

一种设备到设备通信的设备发现装置和方法

该发明公开了一种设备到设备通信的设备发现装置及方法,其中,所述装置包括:接收模块,用于接收网络侧设备发送的资源分配参数,所述资源分配参数分配用于发送D2D信号的周期性资源;以及,用于接收网络侧发送的发送概率指示参数;处理模块,用于至少根据所述发送概率指示参数确定在所述D2D信号的资源周期内是否发送D2D信号,或者,用于至少根据所述发送概率指示参数确定用于发送所述D2D信号的发现资源周期;发送模块,在确定发送所述D2D信号的发现资源周期内发送所述D2D信号。     

激光水下目标探测信号的光学遮挡接收

针对激光水下目标探测信号接收的困难，提出了简单易行的光学遮挡接收方法，蒙特卡罗模拟结果表明，该方法能完全去除接收信号中的海面强反射脉冲和部分海水后向散射包络，同时保证有用的目标反射脉冲基本不受影响。     

水下极板电场通信传输模型研究

针对目前水下到水上跨介质数据传输过程中存在的问题,提出水下部分利用电流场在接收端形成感应电势差完成数据传输。采用有限元仿真水下极板电场通信系统在信号传输时电场的分布情况,通过改变信号频率,极板大小,电导率,介电常数,通信距离及接收端间距等参数,分析对信号传输产生的影响,得到了系统最佳接收间距模型,拟合出最佳接收间距计算公式并进行实验验证,为极板电场通信系统的设计及优化提供参考。     

水下可见光通信节点设计

面向实际的水下通信应用需求,设计实现了水下可见光通信节点,主要包括硬件平台和软件系统两部分.硬件平台以STM32F405RGT6为主控制器,由可见光发送模块、可见光接收模块和电源模块等外围电路构成;软件系统以操作系统和协议栈为主.为了方便内存管理和任务调度,在通信节点的硬件平台上移植了μC/OS II嵌入式操作系统,并实现了基于IEEE 802.15.7可见光通信标准的物理层协议和数据链路层协议.经过测试验证,可见光通信节点可以在水下1m距离范围内进行可靠通信.     

新型水下自重构机器人水下机电对接技术

研究了一种应用于水下自重构机器人的新型水下湿式机电对接技术.采用多卡爪机械锁紧机构和充油密封方式,实现了水下可靠的机械与电气连接;利用机器人逆运动学方法实现关节的协调控制,进行对接过程末端模块的轨迹规划;利用对光电引导传感器组信号的优化来辅助水下对接;成功研制了该水下连接装置和基于该装置的水下自重构机器人样机.通过在样机上的实际应用,验证了该技术的有效性.     

西太平洋远程脉冲声传播实验数据分析

2013年7月在西太平洋进行了一次远程声传播实验.实验使用水下150 m深的拖曳线列阵接收水下125 m深拖曳换能器发射的线性调频声信号(频带范围260–360 Hz),记录了收发距离为34–220 km,612–635 km和926–1029 km等三处的声传播数据;同时用锚系的深水垂直阵潜标接收了水下1000 m深度爆炸的爆炸声信号,最远传播距离达943 km.本文对上述远程脉冲声传播数据进行了分析,获得了深海远程会聚区传播损失曲线、深海声道传播损失及其随接收深度变化曲线,并使用PE模型和射线模型对上述远程脉冲声传播现象进行了理论分析和解释.     

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