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双语推荐：波形恢复

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国内外普遍采用电声脉冲法（PEA）来测量固体电介质中空间电荷的分布。但受固体介质的声学特性和系统频带响应的影响，所测信号的波形会产生畸变，一方面，信号幅值产生衰减，波形脉宽展宽；另一方面，信号产生过冲，严重影响对空间电荷形成机理及分布的判断。针对引起波形畸变的两个主要因素：介质的衰减和色散及测量系统的频带响应引起的非线性相位失真和损耗，综述了国内外关于不同固体电介质形状的空间电荷波形恢复的方法，对比了不同方法的恢复效果，并指出了基于PEA的波形恢复的发展方向和要求。
Both at home and abroad, the pulsed electro-acoustic (PEA) method is commonly adopted to measure the space charge distribution in dielectrics, but the measured signal waveforms will generate distortion because of the impact of acoustic characte-ristics of solid dielectrics and the system band response. On the one hand, signal amplitude attenuates and pulse width broadens;on the other hand, the signal generates overshooting, which severely affects the judgement of formation mechanism and distribution of space charge. In allusion to the two main factors of dielectric attenuation and dispersion causing waveforms distortion, the non-linear phase distortion and loss caused by system band response were measured. This paper described the space charge waveforms recovery method of different solid dielectrics shape at home and abroad and compared the recovery effects, pointing out the devel-opment direction and requirements of waveforms recovery based on PEA.

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为了对任意波形测量技术(OAWM)进行研究，利用高阶非线性光纤中交叉相位调制效应(HNL-XPM)，互相关光学频率分辨光学开关法( X-FROG)，提出了一种测量光学任意波形的新方案。以变换极限脉冲、线性正啁啾脉冲、双脉冲以及任意波形脉冲作为待测脉冲，采用Matlab软件对以上光脉冲光谱图进行了数值模拟，基于矩阵的主元素广义投影算法( PCGP)从数值模拟的光谱图中恢复了脉冲的振幅和相位，误差达到收敛的标准( G<10-5)。结果表明，该方案能够精确地测量任意波形脉冲。
For the sake of studying Optical Arbitrary Waveform Measurement (OAWM),a new scheme of optical arbitrary waveform measurement is proposed using higher-order nonlinear fiber cross-phase modulation effects and cross-correlation frequency-resolved op-tical gating. Then,several common optical pulses spectra are simulated by Matlab software such as transform-limited pulses,linear posi-tive chirp pulses,double pulses and arbitrary waveform pulses and use principal component generalized projects algorithm to retrieve am-plitude and phase of the pulse spectra for the free-noise XPM-XFROG traces,the error of the convergence is criteria ( G<10-5 ) . The re-sults show that this scheme can accurately measure optical arbitrary waveform pulses.

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针对无线电通信中的信号的信源编解码、信道编解码、OFDM和使用直接序列扩频的方法进行扩频通信等相关的关键技术和如何将相关技术进行有效地运用在战术宽带波形的设计进行研究，并与在通信系统建模领域里常用的的MATLAB/Simulink软件仿真技术相结合，实现了一个基于无线通信宽带波形的通信系统，并实现了对该系统后期的OFDM处理。主要创新点体现在使用了模块化的思想来搭建Simulink环境下的仿真系统，以及在仿真中使用OFDM实现了该波形，最后对接收端的信号恢复情况进行检验，取得了良好的效果。
In this paper, firstly the key technology of radio which includes source encode and decode, channel encode and decode, OFDM, and the methods of spread spectrum communication with direct sequence will be researched. And then, how to do the simulation of the technology above will be also researched here. Consequently, a simulation system has been built in the MATLAB/simulink, a software producture well-known in the domain of communication, which can product a broadband waveform based on software radio. The system is improved by OFDM then. Absolutely, the new idea reflects that OFDM and simulink software is serviced for tactics broadband communication. The result of the signal waveform recovered from the receiving part of the system proves that the system can work normally and successfully.

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采用OrCAD16.3软件对AM信号、DSB信号、包络检波器、同步检波器进行建模并仿真,观察到调制解调输出波形,改变参数的值,可观察到恢复出来调制信号失真,验证包络检波器和同步检波器的检波条件。
This paper completed modeling and simulation of AM, DSB, envelope detector, synchronous detector using OrCAD16.3, the waveforms of modulation and demodulation can be observed, changing the values of parameters, the modulation signal distortion can be observed, which verify the detection conditions of envelope detector and synchronous detector.

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待恢复机组的选择是制订黑启动方案的首要任务。分析了影响黑启动阶段机组成功恢复的主要因素，其中重点分析了变压器空载投入时励磁涌流引起的黑启动机组机端电压波形畸变的影响。在此基础上，定义了线路权重、变压器权重和辅机权重，提出了黑启动阶段机组恢复成功率的概念。综合考虑机组恢复成功率和机组容量等因素，对黑启动阶段待恢复机组进行优选。为了减小计算量，首先从所有待恢复机组中筛选部分机组作为寻优集合，并使用前K最短路径算法搜索寻优集合中机组的可选恢复路径。山东电网实际仿真证明了定义的机组恢复成功率的有效性和所述方法的快速性。
The primary task of making a black start plan is to select the to-be-restored unit.The main factors which have an impact on unit restoration are analyzed,especially the terminal voltage waveform distortion of black start unit caused by inrush current when no-load transformers are switched on.Based on the above analysis,the line weight,transformer weight and auxiliary motor weight are defined and the concept of success rate of unit restoration is proposed.The success rate of unit restoration and the capacity of units are considered to select the optimal to-be-restored unit during the black start stage.To reduce the computation burden,several units are selected as a candidate set,whose restoration paths are obtained by the algorithm of K-shortest paths.Simulation results of Shandong power grid show the effectiveness of the success rate of unit restoration and the rapidity of the proposed method.

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目的评价术中神经电生理监测在颈椎手术中的应用价值。方法对56例颈椎病患者行术中体感诱发电位(SEP)及运动诱发电位(MEP)监测,比较术前、术后SEP的变化与颈椎病临床疗效的关系,并以术前、术后JOA评分来评定临床疗效。结果术中SEP波幅上升40例,无明显变化16例。术中监测到MEP波形45例,未监测到MEP波形11例,但术后患者均恢复良好,术前、术后JOA评分差别有统计学意义。其中有1例术中SEP、MEP均正常,但术后出现一过性的四肢活动障碍,立即再次行SEP、MEP检查仍提示正常,术后四肢功能逐渐恢复正常。结论术中神经电生理监测有助于了解术中脊髓的功能状态,联合应用SEP和MEP可以有效预防和尽早检测出颈椎手术中可能存在的神经损伤。
Objective To determine the role of the intraoperative electrophysiological monitoring in cervical spine surgery . Methods Intraoperative somatosensory evoked potential (SEP) and motor e-voked potential (MEP) were performed in 56 patients undergoing cervical spine surgery and the results were estimated by JOA scores for the variation of the JOA scoring before and after the procedure besides the changes between intraoperative SEP ,MEP ,and clinical outcomes . Results 40 patients had SEP in-traoperative increasing ,No significant intraoperative change of SEP were found in 16 patients . A total of 45 patients had MEP signal ,No MEP signal was detected in 11 patients and these patients had good recov-ery . Generally ,postoperative JOA scores were improved significantly in the total patients . Normal in-traoperative SEP , MEP were detected in 1 case , but the limb function temporary deteriorated after surgery ,SEP and MEP were performed immediately ,and the result still be nomal ,the limb fu

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目的分析酒精中毒性脑病患者的脑电图(EEG)改变。方法以酒精中毒性脑病患者为例,选取我院2011年5月~2012年5月30例酒精中毒性脑病患者,作为研究对象。对30例酒精中毒性脑病患者治疗前、治疗后分别进行常规脑电图检查。结果 30例慢性酒精中毒患者治疗前脑电图18例异常,其异常率为60.2%,脑电图异常主要表现为频率变慢,波形杂乱,波幅降低。30例慢性酒精中毒患者治疗后脑电图有2例异常,为不可逆性病理改变。结论治疗前脑电图异常主要表现为频率变慢,波形杂乱,波幅降低;治疗后脑电图频率、波形、波幅都恢复正常。酒精中毒对脑功能的损害是弥漫性的,EEG的改变能为酒精中毒性脑病患者临床提供客观依据,对酒精中毒性脑病的预防与治疗具有极其重要的价值与意义。
Objective To study the changes of EEG alcohol poisoning encephalopathy (electroencephalogram, EEG). Methods 30 cases of patients with alcoholic encephalopathy in our hospital from May 2011 to May 2012 taking the alcoholism encephalopathy were selected as the object of study. The routine EEG was performed before and after the treatment on the 30 cases of patients with alcoholism encephalopathy. Results Among the 30 patients with chronic alcoholism, 18 cases showed abnormal EEG results before treatment; of which the abnormal rate was 60.2%. The abnormality was mainly on the following aspects, the frequency of abnormally slow EEG, messy wave and decreased amplitude. Among the 30 cases of patients with chronic alcoholism, 2 cases showed abnormal EEG results, of which the pathological changes were irreversible. Conclusion The abnormalities of EEG results before the treatment are mainly focusing on slow frequency, wave clutter, and decreased amplitude; but after the treatment, the frequency,

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稀疏微波成像回波数据可以建模为Toeplitz矩阵与地面场景的乘积，Toeplitz矩阵中的行向量为发射信号的时延。由于难于验证Toeplitz矩阵是否符合经典的稀疏信号处理中RIP等重建条件，因而分析稀疏微波成像采样数与发射波形的关系十分困难。近年提出的RIPless理论表明如果矩阵的行向量是对一个概率分布的随机抽取，并且该概率分布满足一定的条件，那么可以从少量的采样数据中恢复稀疏信号。Toeplitz矩阵适用于RIPless理论。该文首先介绍稀疏微波成像中观测矩阵的构造，然后利用稀疏信号处理中的RIPless理论分析波形中信号脉宽、带宽和信号形式与稀疏微波成像采样数的关系，进而比较不同波形对稀疏微波成像中的性能，最后通过仿真验证了该方法的有效性。
Echo data can be modeled as the product of the Toeplitz matrix and reflectivity of the observed scene. The row of the Toeplitz matrix is the time shift of the transmitted signal. Because it is difficult to verify whether the Toeplitz matrix satisfies the reconstruction condition (such as restricted isometry property) of sparse microwave imaging, analyzing the performance of the transmitted signal in sparse microwave imaging is a problem. RIPless, a new progress in sparse signal processing, shows that if the row of the matrix is an independent and identically distributed (i.i.d.) random vector drawn from a distribution, and this distribution satisfies certain conditions, then one can faithfully recover approximately sparse signals from a minimal number of measurements. The Toeplitz matrix satisfies RIPless. In this paper, we introduce the construction of the measurement matrix in sparse microwave imaging. Further, the relationship between pulse duration, bandwidth and waveform type, and

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针对现有电、磁刺激系统参数调节存在的不足,设计了一种利用动态脑电地形图反馈调节的经穴磁刺激系统.该系统磁刺激发生模块基于DDS技术,利用单片机编程产生刺激波形、幅度、频率可调的刺激信号,功率放大后,经喇叭状刺激线圈产生磁场,作用于人体穴位.脑电仪在线检测大脑的脑电信号,经计算机数据处理,实时显示大脑α波动态脑电地形图,并反馈调节磁刺激强度、刺激频率和刺激波形.结果表明,该系统可以优化经穴磁刺激的输入方式,改善大脑α波能量,促进脑瘫病人神经系统恢复和康复训练.
For the deficiencies of parameter adjustment in the existing electrical ,magnetic stimulation sys-tem ,a meridian magnetic stimulation system of feedback regulation using the dynamic brain electrical activity mapping (BEAM ) was designed .The magnetic stimulation module of this system generated adjustable elec -tromagnetic stimulation signals on waveform ,intensity ,frequency using DDS technology and programming by MCU .After these signals were amplified ,a magnetic field generated by a trumpet -shaped coil effected on the acupuncture point of human .The electroencephalograph detected the EEG signal online .EEG data was pro-cessed by computer .A dynamic BEAM of brain’s α-wave was displayed and used to adjust the magnetic stim -ulation intensity ,stimulation frequency and stimulation waveform .The results showed that this system can optimize the input of meridian magnetic stimulation ,improve the brain’s α-wave energy ,and promote the recovery of nervous system and the sel

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综合对比4种波形重跟踪算法,选择改进阈值法处理Jason-1GM数据,联合波形重跟踪后的Geosat和ERS-1GM数据,沿轨2Hz重采样以提高数据空间分辨率。通过数据质量控制剔除粗差数据,考虑海表面地形的影响,基于移去-恢复法和维宁-曼齐兹公式反演了中国近海及邻近海域（0°～45°N,100°～140°E）1′×1′的精细重力场。船测数据检核表明反演结果在开阔海域精度约4mGal,近岸浅水区约10mGal,均优于DTU10和V21.1模型。
The advanced threshold method was selected for processing the Jason-1 geodetic mission waveform data based on the comparative analysis of four waveform retracking methods.Combined with the retracked ERS-1 and Geosat geodetic mission data,the along-track data were resampled at 2Hz to improve the spatial resolution of coast-al areas.Considering the influence of sea surface topography after the data quality control process,a refined 1′×1′resolution gravity field of the China sea and its adjacent sea areas(0°~45°N,100°~140°E)was obtained by remove-restore method and Vening-Meinesz formula.The validation with shipborne data showed that the accuracy of in-version result is about 4 mGal and 10 mGal in open seas and shallow water areas,respectively.Moreover,the inver-sion result is better than both of the DTU10 model and the V21.1 model.

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