单频的

This paper introduces a single-carrier system with hybrid time-frequency domain Decision Feedback Equalization, in which the short pn (Pseudo-Noise) sequence with fixed waveform replaces the cyclic prefix in the conventional Single Carrier systems with Frequency Domain Equalization, and the long PN sequences composed of several short pn sequences are employed as the channel training sequences to complete the initial estimation and tracking for fast-varying channel.

摘要该文设计了一种联合判决-反馈均衡的单载波频域均衡系统，该系统用固定波形的短pn序列取代常规SC-FDE系统中的循环前缀，并以多个短pn序列组成的长PN序列作信道训练从而解决快变信道的初始估计和跟踪问题。

Chapter Two Further Study On Two Types of Tone Sandhis Supposed by Traditional Dialectology The further study is relied on the research of F0 and elapsed time, and more phonetic dealing with the original data.

对这一问题的分析将基于论文第一章所论述的上海方言单音节声调和两类变调的声学特性（基频F0和时长两因素），以及在这两个基本声学特性上所作的语音学意义上的对数据的进一步处理。

The appearance of Fast Fourier Transformation algorithm and DSP chip provides a uniform, economical and singlechip integration resolution method.

频谱分析在生产实践和科学研究中有着广泛的应用，快速傅立叶变换算法和DSP芯片的出现，为各式各样的频域问题提供了一个统一的、经济的、单片集成的解决方法。

Base on the in-depth analysis into the phase-to-ground fault mechanism and its features, the new concept is presented, which is to change the reference signal for analyzing and processing from the steady signal to the transient signal in a fault case A new principle of the fault feeder line selection with the synthetic logical criterion is presented creatively, which is based on the waveform recognition of the selected time-frequency window.

在深入分析单相接地故障的机理及故障特征的基础上，提出了从基于稳态信号原理转到基于故障暂态信号去分析和处理的新概念；创造性的提出了基于选线时频窗波形识别的综合性逻辑判据的故障选线新原理。

Based on the single-particle theory, we inspect the effects of harmonic wiggler field components on the outputs of free electron lasers (including the components of fundamental and harmonic frequecies), and derive the complete simulation equations for millimeter wave FELs. Meanwhile under the condition that the harmonic wiggler fields are much smaller than the fundamental one, we describe the effects simulated. Using the improved 3D WAGFEL code.

在单粒子理论的基础上，详细考察了摇摆场谐波分量对自由电子激光输出功率的影响，给出了完整的模拟方程组，并在摇摆场谐波振幅远小于其基波振幅值的假定下，利用三维WAGFEL程序和毫米波自由电子激光放大器的参数模拟计算了摇摆场谐波对自由电子激光基频输出功率的影响。

The conditions to measure accurately and the principles to select parameters of the multi— probes EST method are proposed, and the theoretical research, computer imitation and the experiment on a machine tool prove that these principles and suggestion are necessary and effective. The influence of the initial value errors of the probes, the installation error of the probes system, and the remaining error caused by the radical error motion are analyzed quantitively on the measurement accuracy of the multi—probes EST method. The influence of the error caused by the probe's axes which is not in a plane and the perpendicularity error of the plane which the probe's axes is in to the stational axis are discussed on the measurement results.

结合理论分析，对这些EST方法进行了计算机仿真分析和研究，重点研究了这些方法的应用条件和误差分离精度，所得出的结论是：三测头法EST基本上能实现各项误差的完全分离，适于在位测量使用；二测头法在恰当地选择测头安装角的条件下，可以得到较高测量精度，适于大型零件圆度、圆柱度、径向圆跳动和全跳动的在位测量；对置两测头时域法可以在一定程度上改善单测头法测量精度，但对随机径向误差无能为力；对置两测头频域法存在严重的谐波损失。

The principle and the mathematical model of reduced-dynamic precise orbit determination are discussed based on precise point positioning technique by zero-differenced dual-frequency P codes and epoch-wise differenced carrier phase data. Then the key issue in the reduced-dynamic POD, i. e. the pseudo stochastic pulses and their impact on orbit determination accuracy are analyzed.

论述了基于低轨卫星星载GPS双频观测值的精密单点定位技术的简化动力学定轨方法的数学模型，分析了简化动力学定轨中的关键问题―伪随机脉冲的设置问题及其对定轨精度的影响。

In this paper, the acoustic characteristic of bubbles and the interaction with tissue are studied by the experiments of sonoluminescence, the simulations and comparison of dynamics characteristic of gas bubbles and shell encapsulated bubbles, and the interaction between bubbles and tissue using single-frequency mode and dual-frequency mode ultrasound.

本文从空化气泡的声致发光实验、理论求解和比较带球壳微泡和空化气泡的动力学特性，和微泡在单双频超声换能器下的与生物组织的作用效果出发，研究微泡的超声特性以及微泡对生物组织的作用效果。

By simulating the absorption spectrum of molecule iodine absorption filter ranges from 470nm~550nm, this paper selects the absorption spectrum of molecule iodine absorption filter that satisfies the requirement of frequency discriminator in detecting system and ascertains the center emission frequency of laser emitter.

以基于边缘探测技术的激光雷达监测大气信道和海洋水下信道环境参数为例，通过仿真出碘分子吸收滤波器在470nm～550nm区间范围内的吸收光谱谱线，选择出合适的吸收谱线并确定发射激光信号的中心频率，并在此基础上，给出了满足探测要求的激光发射信号单稳频指标，为实际探测系统的设计奠定基础。

Roger since the invention of the transistor oscillation push-pull single transformer DC converters, is to achieve high-frequency conversion control circuit beginning in 1957 the U.S. investigation self-invented the push-pull Two-transformer, 1964 U.S. scientists have proposed abolition of the frequency of the series switching power supply transformer, as envisaged in this power to the volume and weight of the decline was a fundamental way.

Roger发明的自激振荡推挽晶体管单变压器直流变换器，是实现高频转换控制电路的开端，1957年美国查赛（Jen Sen发明了自激式推挽双变压器，1964年美国科学家们提出取消工频变压器的串联开关电源的设想，这对电源向体积和重量的下降获得了一条根本的途径。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷