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First, the stations'timing process and the slot aligning are discussed. Second, the dissertation propose a resource request random access method based on feedback. The performances of this method are analyzed. Third, proceed from the considerations of the MAC protocol for the HFC system, a QOS-oriental scheduling algorithm for the MAC protocol based on dynamic TDMA is proposed. Simulation results show that the performance of this algorithm is better than that of the first come first service. Forth, two contention resolution algorithms ----p-persistent CRA and tree CRA, which are usually adopted in the HFC system, are summarized. The delay and characteristic are compared. At last, the dissertation introduces the function implementation of the MAC layer based on COM21 UPSTREAMS.

首先，讨论了基站的同步进程和时隙同步的实现；然后，本文提出了一种带反馈模块的资源申请信号随机接入方法，并对其进行性能分析；然后，从HFC系统的MAC协议出发，提出了一种用于基于动态TDMA技术的MAC协议的业务安排算法，计算机仿真结果表明其性能优于先到先服务法的性能；然后概述了常用于HFC系统的两种冲突解决算法——p-坚持冲突解决算法和树型冲突解决算法，比较两者的时延性能与特征；最后，介绍了基于COM21 UPSTREAMS协议的MAC层功能实现，给出了硬件框图和照片。

To increase the security of the watermark, a new binary image encryption algorithm based on TD-ERCS map is presented. The watermark is encrypted by a chaos sequence generated by TD-ERCS map; A novel color image watermarking algorithm is proposed based on discrete chaotic map and 2-dimensions discrete wavelet transform. The watermark is encrypted by the new binary image encryption algorithm, and the encrypted watermark is embed into four sub-bands of the most deep level of blue branch of host image by three-level wavelet transform, and the embedded positions are determined by general cat cha otic map; A novel color-image blind detection watermarking algorithm is proposed based on integer wavelet transform and subsampling. The scrambled watermark is encrypted and embed into the low sub-bands after four sub-images of the Y branch of host image is transformed by two-level wavelet transform, and the embedded positions are determined by Logistic chaotic map, this watermarking scheme can realize blind extraction.

为了提高水印图像的安全性，提出了一种基于TD-ERCS混沌映射的二值水印图像的加密算法，该算法利用TD-ERCS映射产生的混沌序列加密水印图像；将离散混沌映射和二维离散小波变换相结合，研究了彩色图像水印新算法，该算法先对混沌序列加密后的水印图像进行小波变换，再嵌入到宿主图像的蓝色分量的最深层的四个子带中，嵌入位置则由广义猫映射确定；将整数小波变换和图像子采样技术应用于数字水印，提出了一种彩色图像盲提取水印算法，水印嵌入时，先对宿主图像在YIQ色彩空间中的Y分量进行子采样，并对得到的四个子图像分别进行二级离散小波变换，然后将置乱并加密后的水印图像嵌入到小波变换后的低频子带中，其嵌入位置由Logistic混沌映射产生的混沌序列确定，实现了水印的盲提取。

Slipform assembly prior to checks based on the actual location, size and design drawings of the location, size deviation (based on the design of the center coordinates of the displacement of ≯ 15mm, based on population Cup Neijing Neijing error of not more than 1%).

滑模组装前，先检查基础的实际位置、尺寸与设计图纸的位置、尺寸偏差（基础中心点对设计坐标的位移≯15mm ，基础杯口内经误差不大于内经的1%）。

The innovation of this paper can be explicated as the following:First, based on the spatial concepts of cadastral feature this paper presents "general block" and "general land parcel".Second, based on "general block" and "general land parcel" this paper presents the urban and rural integrative cadastral management model, and then combined with Geodatabase it introduces design of the urban and rural integrative cadastral database, and based on this the urban and rural cadastral data can be stored in the same database by the same way.

本文的主要工作集中在以下几个方面：第一，在基于地籍要素的空间概念支持下，提出了&广义街坊&和&广义宗地&的概念；第二，在&广义街坊&和&广义宗地&概念的支持下，提出了城乡一体化的地籍管理模型，并结合Geodatabase阐述了城乡一体化地籍数据库的设计，从而真正地实现了城乡地籍数据的统一存储。

Based on the above-mentioned parameter, according to the relationship between robust estimation and nonlinear diffusion, the Turkey loss function is introduced as the diffusion function in SAR image decomposition because of its better performance, and the contour of an image is extracted by the Turkey diffusion function with the proposed diffusion parameter mentioned above. The experiment results indicate that the Turkey loss function based diffusion process can strengthen the conspicuous contour. Additionally, a Raita\'s criterion-based method, solving the automatic diffusion threshold, is proposed to automatically set the threshold in diffusion decomposition.

针对基于梯度参数和局域方差系数的扩散在对SAR图像进行分解时存在的缺陷，提出了一种局域方差系数与窗口幅度均值积的扩散系数，该系数能够更有效地实现潜在目标区域和背景区域的区分；在此基础上，根据鲁棒估计与非线性扩散的联系，引入扩散效果更好的Turkey损失函数作为图像分解中的扩散函数，并结合局域方差系数与窗口幅度均值积的扩散参数来提取图像的轮廓，结果表明：基于Turkey损失函数的扩散过程对特征突出的边缘所起的&强化作用&更加明显；此外，针对扩散分解中的阈值确定问题，提出了一种基于拉依达准则的扩散阈值自动求解方法，实现了扩散阈值的自动求解。

Based on probability theory, a method for describing and calculating the collision probability between rendezvous and docking vehicle and debris is presented, and the method involves quantitatively analyzing the collision probability using quasi maximum instantaneous collision probability and total collision probability. The method calculating the indexes is developed, and the input required to perform a calculation includes the respective state vectors, position error covariance matrices and physical sizes of objects involved.(3) Two methods to analyze relative trajectory safety between chaser and target are developed, which are 3-sigma ellipsoid based methodology and collision probability based methodology.

1分析了交会对接各阶段面临的主要轨迹安全威胁，阐述了被动和主动安全策略、目标器的交会对接控制区域等保证交会安全的措施；(2)基于概率思想发展了线性和非线性运动情况下飞行器与空间碎片的碰撞判断方法，提出采用总碰撞概率和拟最大瞬时碰撞概率来综合描述飞行器与空间碎片的碰撞危险程度，推导了通过飞行器和空间碎片各自的状态矢量、位置误差协方差矩阵以及形状尺寸来计算碰撞概率的公式；(3)提出了两种分析追踪器和目标器之间相对轨迹安全的新方法：基于3σ椭球的轨迹安全分析方法和基于碰撞概率的轨迹安全分析方法。

The transmission and print system for shunting trip plan is the important part of railway marshalling station management information system, whose first generation is based on the transmission system of IPC and the second generation is based on embedded and dedicated transmission gateway system. Based on this, the paper studies and proposes a system structure suitable for remote maintenance and management and further optimizes the control of information flow.

钩计划传输与打印系统是铁路编组站信息管理系统的重要内容，第一代是基于工控机的传输系统，第二代是基于嵌入式专用传输网关系统，在此基础上，研究提出了适合于远程维护和管理的系统架构，并对信息流控制做了进一步优化。

The main products are various types of machinery parts, automobile and motorcycle spare parts, textile machinery parts, including gears, timing belt pulleys, all kinds of internal and external cam, connecting rod, bushings, and other powder metallurgy products, including copper-based materials, iron-based, copper Fe-based and other high-strength alloy series.

主要产品有各类机械零件，汽摩零配件，纺织机械零件，包括齿轮、同步带轮、各种内外凸轮、连杆、轴套等各类粉末冶金制品、材质包括铜基、铁基、铜铁基及其他高强度合金系列。

At first, in this paper the background and basic principle of VoIP are introduced; the much popular VoIP technology based on H.323 protocol is studied; based on the function and main working process of IP telephone system, the principle of coding of compression and transfer technology of the real-time voice are analyzed; depended on the existed experimental environment, the program of voice part of PC to PC video telephone terminal based on LAN is designed and implemented; and the problems encountered during the design of program have been analyzed and solved.

本文首先介绍了IP电话的发展简史，IP电话技术原理；对目前最为流行的基于H.323协议的VoIP技术进行了研究；根据IP电话系统的功能和主要实现过程，分析实时语音压缩编码技术和传输技术原理；利用实验室现有的实验环境，设计并基本完成了一种基于局域网的PC to PC可视电话语音部分的编程；并对程序设计过程中所遇到的问题进行了分析和解决。

A method for use in a DPC includes: receiving ( 400 ) a control signal based on a desired output signal that identifies a first output tap on the delay line; based on the control signal, selecting ( 410 ) at least two output taps on the delay line for receiving at least two different phase-shifted clock signals; and generating ( 420 ) an output signal based on the control signal and the received phase-shifted clock signals that is substantially the desired output signal.

在DPC内使用的方法包括：基于期望的输出信号接收(400)用于识别该延迟线上的第一输出抽头的控制信号；根据该控制信号，在该延迟线上至少选择(410)两个输出抽头，以至少接收两个不同相移时钟信号；以及根据该控制信号和收到的基本上是期望的输出信号的相移时钟信号，产生(420)输出信号。

Through comparing with the results by simulation to study the effects of theprojectile"s final velocity, the angle of rotation and the ballistic trajectory"s migration withdifferent projectile"s rotating speeds, different target"s moving speeds and differentpenetration angles.

通过比较数值模拟的结果来研究不同弹头转速、目标速度、侵彻角对侵彻过程中弹头最终速度、翻转角度和弹道偏移的影响。

I love stationery and all the accoutrement of writing.

我爱文具以及所有的书写的工具装备。