Research of Underwater Acoustic Communication Signal Modulation Recognition and Its Implementation

随着海洋开发、海洋权益维护、国防安全等领域信息获取和处理需求的不断提升，对水声通信信号的调制样式的自动识别研究成为重要的研究课题。然而目前无线领域常用的通信信号(BPSK，QPSK，MFSK，OFDM)的调制识别方法往往需要较多的调制参数作为先验知识（如精确载波频率、初始相位、符号速率）。由于水声信道的随机时-空-频变、窄带高噪、多途效应及多普勒频移等特性，使得上述这些先验知识在水声信号调制方式未知的情况下很难得到，因此，非合作水声通信信号的自动识别极具挑战性。 信号频谱是对信号在频域方面的一种描述，不同调制方式的信号，在频域上表现为不同的形式。信号功率谱及其二次方谱可以较好的反映出MFSK...With rapid development of ocean exploitation, maritime rights protection and other marine information acquiring and processing related fields, the modulation recognition of underwater acoustic communication has become an important research topic. At present, the modulation recognition method of commonly used communication signal in wireless field, such as based on instantaneous features, based on ...学位：理学硕士院系专业：海洋与地球学院_海洋物理学号：2232013115144

A two-level remote control system of acoustic release transponder

水声释放器在海洋环境监测、水下施工和海洋测绘等领域发挥着重要作用。考虑到长期值守对低功耗的要求,传统水声释放器采用简单的非相干频率调制解调方法进行遥控,要求遥控信号有较高的信噪比,因此易被非授权方截获、复制从而导致丢失。基于STM32微处理器设计了一种频率调制结合扩频调制的二级触发释放器遥控系统,该系统在通过作为第一级触发的频率检测后,需对低信噪比扩频信号检测进行二级触发,从而提高系统的可靠性、安全性。海上实验结果表明了该方案的有效性。The acoustic release transponder plays an important role in marine environmental monitoring, underwater construction and marine mapping, and so on. Taking into account the low power requirements to support long lifetime, the traditional acoustic release transponder uses simple frequency modulation and demodulation for signal detection, thus the remote control signal is easily intercepted and copied by unauthorized user. To improve the reliability and safety, a scheme of developing a two-level remote control system is presented by incorporating the classic frequency modulation with the spread spectrum modulation. With the proposed method, following the non-coherent detection of frequency modulation signals, the receiver needs to detect the low SNR spread spectrum signal to finish the two-level remote control. Based on STM32 microprocessor, the design and implementation of the proposed scheme is provided. The offshore experimental results validate the effectiveness of the proposed method.国家自然科学基金资助项目(11274259

Modulation Recognition Method of Non-cooperation Underwater Acoustic Communication Signals Using Principal Component Analysis

由于信道传输特性、信噪比低等因素的影响,非合作水声通信信号的调制识别极具挑战性。对信号功率谱、平方谱进行主分量分析,提取代表不同类型调制信号特有信息的主分量作为特征参数,从而降低特征参数维度、抑制噪声影响,并在此基础上设计一种基于人工神经网络的水声通信信号调制方式分类器。海上实录信号数据的识别实验结果表明了该方法的有效性。The modulation classification of the non-cooperation underwater acoustic communication signals is extremely challenging due to channel transmission characteristics and low signal-to-noise ratio. The principal component analysis( PCA) is used to analyze the power spectra and square spectrum features of signals,which is capable of extracting the principal components associated with different modulated signals as input vector,thus reducing the feature dimension and suppressing the influence of noise. An artificial neural network( ANN) classifier is proposed for modulation recognition. The experimental modulation classification results obtained from field signals in 4 different underwater acoustic channels show that the proposed modulation recognition method has good classification performance.国家自然科学基金项目(11274259、11574258

Modulation recognition of underwater acoustic OFDM signals based on the correlation property of the cyclic prefix

为解决非合作通信系统中水声OFDM信号的类型识别,本文研究水声OFDM通信信号与常见单载波水声数字通信信号(MPSK,MFSK)之间的调制识别问题。考虑到水声信道复杂传播特性对循环前缀相关性的影响,本文通过截取信号前后片段并迭代搜索双相关峰进行无需先验知识的水声OFDM通信信号特征参数提取,在此基础上设计了一种基于模糊系统的水声OFDM通信信号识别器。对不同信道条件下海上实录信号数据的识别实验结果表明了本文方法的有效性。In order to identify the type of underwater acoustic OFDM signal in non-cooperative communication system,in this paper,the method to discriminate the orthogonal frequency division multiplexing(OFDM)from common single-carrier digital underwater acoustic communication signals(e.g.MPSK,MFSK)over underwater acoustic channels has been investigated.Considering the correlation characteristics of the cyclic prefix(CP)at the presence of the doubly selective underwater acoustic channels,an iterative dual-peak searching strategy is proposed to extract the CP correlation peak feature without prior knowledge,as the input vector of a fuzzy recognition system for modulation recognition of OFDM signals.The experimental results of modulation classification obtained with field signals at three different underwater acoustic channels show that the proposed method has good performance.国家自然科学基金项目(11274259,11574258);; 福建省自然科学基金项目(2015J01172

Therapeutic Observation ofNa Zhi Method plus Electroacupuncture for Poststroke Uninhibited Neurogenic Bladder

目的 观察纳支法结合电针治疗中风后无抑制性神经源性膀胱的临床疗效.方法 将120例脑血管病变引起的无抑制性神经源性膀胱患者随机分为治疗组和对照组,每组60例.治疗组采用纳支法结合电针治疗;对照组采用电针疗法.每日1次,每次30 min,治疗2星期.观察两组治疗前后日排尿频率测试分度和膀胱最大容量的变化,并比较临床疗效.结果 治疗组总有效率为98.2%,愈显率为89.5%;对照组总有效率为93.1%,愈显率为72.4%.两组愈显率比较,差异有统计学意义（P〈0.05）.两组治疗前日排尿频率测试分度比较,差异无统计学意义（P〉0.05）;两组治疗前后日排尿频率测试分度比较,差异有极显著统计学意义（P〈0.01）;治疗组治疗后日排尿频率测试分度与对照组比较,差异有统计学性意义（P〈0.05）.两组治疗前膀胱最大容量比较,差异无统计学意义（P〉0.05）;两组治疗前后膀胱最大容量比较,差异有极显著统计学意义（P〈0.01）;治疗组治疗后膀胱最大容量与对照组比较差异有统计学意义（P〈0.05）.结论 电针治疗无抑制性神经源性膀胱疗效显著,结合纳支法疗效明显优于单纯电针.Objective To observe the clinical efficacy of Na Zhi method （midnight-noon ebb-flow method） plus electroacupuncture in treating poststroke uninhibited neurogenic bladder.Method A total of 120 patients with uninhibited neurogenic bladder due to cerebrovascular diseases were randomized into a treatment group and a control group, 60 cases in each group. The treatment group was intervened by Na Zhi method plus electroacupuncture; the control group was intervened by electroacupuncture. The intervention was conducted once a day, 30 min each time, for a total of 2 weeks. The daily voiding frequency index and maximum cystometric capacity （MCC） in the two groups were measured before and after the intervention, and the clinical efficacies were compared.Result The total effective rate and markedly effective rate were respectively 98.2% and 89.5% in the treatment group versus 93.1% and 72.4% in the control group. There was a significant difference in comparing the markedly effective rate between the two groups （P〈0.05）. There was no significant difference in comparing the daily voiding frequency index between the two groups before the intervention （P〉0.05）; the daily voiding frequency index was significantly changed after the intervention in both groups （P〈0.01）, and the daily voiding frequency index of the treatment group was significantly different from that of the control group after the intervention （P〈0.05）. There was no significant difference in comparing the MCC before the intervention between the two groups （P〉0.05）; the MCC was significantly changed after the intervention in both groups （P〈0.01）; the MCC of the treatment group was significantly different from that of the control group after the intervention （P〈0.05）.Conclusion Electroacupuncture can produce a significant efficacy in treating uninhibitedneurogenic bladder, while it can produce a more significant efficacy when combined withNa Zhi method

Underwater acoustic speech communication using time reversal and time-frequency differential ofDM methods

针对水声信道多径、时变、多普勒等恶劣传输特点对水声语音通信的严重影响,本文采用多通道时间反转和时频差分OfdM进行水声语音通信技术方案设计,该方法首先通过多通道时间反转进行时间域和空间域多径聚焦,进而结合时频差分OfdM调制解调抑制残留多径的影响。由于无需采用信道估计和均衡算法,系统实现方便、复杂度低,同时对信道具有一定程度的稳健性。该方法语音压缩编码采用混合激励线性预测编码。仿真实验和海试实验表明了本文方案的有效性。The difficulties of underwater acoustic channel, i.e., multipath, time varying and Doppler shifting pose significant challenges to underwater acoustic speech communication.In this paper, multi-channel time reversal is incorporated with time-frequency differential orthogonal frequency division multiplexing(ofDM)technology to design an underwater acoustic speech communication system, which enables time-frequency domain focusing of multipath by multi-channel time reversal, as well as suppressing of the residual multipath with time-frequency differential ofDM.Thus the employment of complicated channel estimation and equalization are avoided to facilitate the low complexity system implementation.In addition, the mixed-excitation linear predictive(MELP) is employed for speech encoding.The simulation and sea trial demonstrate the effectiveness of the method at presence of time varying multipath underwater acoustic channel.国家自然科学基金资助项目(11274259

Highly-efficient SPT arithmetic of fast freecube calculation

分析了目前国内外数据立方体计算的研究现状,首先在free-set的概念上,挖掘free-set的性质,建立了FreeCube的概念结构。然后基于BUC算法,充分考虑到free-set的性质,在对维划分的选择和free-set判断上去掉了不必要的划分和判断,从而提出了一种计算FreeCube的高效算法SPT,最后从多个角度进行了实验,并与相关工作做了对比,证明该算法具有一定的优越性。The current domestic and international research situation of data cube calculation are analyzed.Its merits and demerits are pointed out.The free-set property is excavated and the concept construction of freecube on the free-set conception is established.With regard to freecube calculation,fully considering the free-set characteristics while combining the characteristics of BUC's cal-culation,an efficient calculation way SPT is put forward.After the related work is compared,the result show the superiority of the algorithm.浙江理工大学科学基金项目(111251A4Y04002

靶向Neuropilin-1的抗肿瘤研究进展

Neuropilin-1(NRP-1)又称神经鞭毛素蛋白,是一个大小为130～140 kD的非酪氨酸激酶跨膜蛋白,参与脊椎动物胚胎的神经和心血管系统发育。它作为一个多功能受体调节VEGF(血管内皮生长因子),PDGF(血小板衍生生长因子),bFGF(成纤维生长因子)等细胞因子的信号通路,与肿瘤血管新生和肿瘤转移密切相关。NRP-1被认为是一个新的肿瘤治疗靶点,近年来针对NRP-1为靶点的药物研究有不少新进展。本文主要介绍NRP-1的生物学特征,对肿瘤作用以及相关药物研究

Dynamic Selection of Materialized Views of Multi Dimensional Data with a Multi-Users and Multi Windows Method

多维视图动态维护是数据仓库领域当前研究的一个热点 随着数据仓库的普及 ,将有越来越多的各种类型的用户使用OLAP工具满足各自特定的分析需求 现有的各种视图选择方法没有考虑不同类型用户的特点 ,从而存在一些缺陷 提出多用户多窗口方法 ,充分考虑用户的差异 ,利用单个用户在查询时的相对有规律性 ,为用户划分级别 ,并为每个用户设置相应级别的用户视图窗口 ,从而合理地利用了系统有限的资源 ,提高了查询响应速度 ,也保证了特殊用户对查询性能的特殊需求 ;给出了相关的定义和MUMW算法 ,并阐述了多用户多窗口方法的优点Dynamic selection of materialized views of multi dimensional data is one of the most researched aspects in the field of data warehouse; With the increasing use of data warehouse, there will be accordingly more and more different kinds of users making use of OLAP tools to complete their analytical work; The existing methods being used to select views do not take into account the characteristic of various kinds of users, and therefore have some defects; A multi users and multi windows method is presented here, which considers the disparity among various users and makes use of the rule of the users' queries In the method, all users are divided into three groups with different grade and each user is accordingly endowed with user view window of certain grade Such method leads to the reasonable use of the limited space resource and also speeds up the response of query, which stipulates satisfying some special needs of certain user; Some related conceptions and MUMW algorithm are also put forward here, and at the same time, the advantages of this method are described福建省自然科学基金项目 (A0 3 10 0 0 8);; 福建省高新技术研究开放计划重点项目 ( 2 0 0 3H0 43

Control method for aircraft wake vortex based on Rayleigh-Ludwig instability

在飞机飞行的过程中尾涡会伴随着升力产生,威胁后机的飞行安全.在简化机翼模型上添加扰流片,通过一个矩形翼以引入一个与主翼尾涡大小不同、方向相反的小涡,构建尾流自消散四涡系统,以期诱发尾涡的rAylEIgH-ludWIg相交不稳定性.通过改变扰流片的大小形状,调整模型的攻角和拖曳速度,采用粒子图像速度场仪测量系统定量研究在低雷诺数下单主翼尾涡发展特性以及双涡相互作用特性.研究表明:在未添加扰流片时,尾涡环量在45个翼展内相对于初始环量基本保持不变;在添加扰流片的情况下尾涡的环量衰减可以达到35%~55%,而未添加的基本翼型的尾涡的环量则几乎保持不变,这说明添加适当的扰流片能诱发尾涡的rAylEIgH-ludWIg相交不稳定性,加速尾涡的消散,当小涡和主涡的初始环量比为-0.489、初始距离比为0.5时,45个翼展范围内,尾涡环量衰减55.9%.本文系统性的实验结果可以为低尾流机翼的设计提供参考依据.The aircraft wake vortex is an inherent flow phenomenon due to the lift generation mechanism,which has a negative impact on the flight safety.By adding a set of specially designed spoiler,a rectangular wing was designed to generate a pair of weaker vortices,which had different sizes and opposite direction compared to main wing vortices,thereby constructing a self-destructive four-vortex wake system to induce Rayleigh-Ludwig instability.Under different experimental conditions,in terms of changing the size or shape of the spoiler,towing speed and angle of attack,the wake vortex development of the test model,that both with and without spoiler,as well as the circulation analysis,were acquired particle image velocimetry( PIV) measurements under the low Reynolds number.The study demonstrates that the decrease in circulation was 35% to55% in 45 wingspans when spoilers are introduced,whereas the counterpart of the baseline airfoil,without spoilers,is nearly kept steadily,which reveal the application possibility of Rayleigh-Ludwig instability in alleviating the wake vortex.As the initial circulation ratio equals to- 0.489 and the initial distance ratio is0.5,the circulation of the primary vortex reduce most significantly( 55.9%) in 45 wingspans.Results would provide a scheme in the design of airfoils with weaker vortices.国家自然科学基金(11072206