自跟踪

to reduce the impact of carrier frequency offset in ofdm system,this thesis designs a new carrier frequency offset estimation scheme for ofdm system.the carrier frequency offset estimation includes acquisition and tracking.we adopt variable step size adaptive algorithm.the acquisition range of the proposed algorithm is as large as one half of the overall signal bandwidth.through this method we can not only avoid the feedback by using forward error correction,but also reduce the times of complex multiplication in order to reduce the power consumption of the system.this algorithm not only has low complexity and fast convergence nut also can improve the demodulation performance of ofdm system.computer simulation illustrates the superior performance of the proposed algorithm with regard to estimation accuracy in both awgn channel and multi—path channel.

摘 要：为了减小正交频分复用系统受频率偏差的影响，在ofdm系统中设计了一种新的载波频偏估计算法。频偏估计包括跟踪和捕获两个阶段，文中采用变步长自适应算法来进行跟踪，这个跟踪算法的捕捉范围是整个信号带宽的一半。通过此方法，不但可以利用前向纠错的方式来避免反馈，而且可以缩减复数乘法的次数以降低计算复杂度和系统功耗。该方法运算复杂度低，并具有较好的收敛性，能改善odfm的解调性能。从计算机的仿真效果可以看出无论是在awgn信道上还是在多径信道上都表现出了卓越的性能。

Based on a lot of empirical analysis, the author summerizes that the historical premises of mergers in the United States include of the development of modern-enterprise、the technical innovation、the expansile demand and the development of capital market, surveys the developments and characters of mergers in the United States. From Marx's capital concentration theory to the arguments between structure school and conduct school, from the theories of economists at the present age abroad to the achievements of the learned men in China. the author surveys the theorical developments of merger. Making a clear definition of the concept and premises of self-organizational merger on the hypothesis that enterprise is a kind of self-organization, futhermore, the author constructs the theoretical frame of self-organizational merger.

主要内容有：在对大量实证材料分析的基础上，归纳出美国企业兼并的历史前提是现代企业形成与发展、技术上的创新、市场需求的扩大和资本市场的发展，阐释了美国企业兼并的历程与特点；从马克思的资本集中理论，到结构主义与行为主义的争论与分歧，从当代经济学家们的若干理论，到中国学者对企业兼并的认识，跟踪考察了企业兼并理论的起源与发展；从企业是自组织系统的假设出发，界定了企业自组织兼并的内涵，提出了企业自组织兼并存在的条件体系，构建了市场结构、企业自组织兼并行为、产业绩效、政府调控的企业自组织兼并理论的SCPG分析框架，分析了企业自组织兼并理论的贡献。

In our thesis, contents are organized as following In Chapter 1 we present our topic's internal and overseas research situations, theoretical and practical significance, and introduce the research object and contents, and the main contributions of this dissertation. Chapter 2 reviews the development of the stability results for nonlinear systems and some relevant recent results, which include Lyapunov and LaSalle-Yoshizawa theorems for nonlinear systems, and stochastic edition for stochastic nonlinear systems. Sontag's formula for systems affine in control is presented in the frame of CLF. The concepts of disturbance attenuation and the inverse optimality are also explained in this Chapter. In chapter 3 we present the solvable theorem of inverse optimal gain assignment problem, design the inverse optimal controller and the inverse optimal tracking controller for strict-feedback nonlinear continuous systems with unknown time-varing bounded disturbances and constant unknown parameters using an adaptive backstepping algorithm, which are nonlinear, continuous and are easier to realize. These designs are fully systematic and the algorithm can be directly coded in symbolic software. The results of simulation show the effectiveness of the control algorithms.

论文的结构如下：在第1章中，给出了本文研究课题的研究现状、理论意义和实际应用，并介绍了本文的研究对象、研究内容以及主要贡献；在第2章中，针对确定性非线性系统和随机非线性系统，分别介绍了Lyapunov定理、LaSalle-Yoshizawa定理及其随机版本；对仿射系统，在控制Lyapunov函数框架下，给出了Sontag公式；同时给出了非线性系统扰动抑制和逆最优控制问题的基本概念；在第3章中，针对具有未知时变有界扰动和未知定常参数的一类不确定非线性系统，给出并证明了逆最优增益配置可解定理，使用自适应Backstepping算法和均值定理，系统地设计了自适应逆最优控制器和逆最优跟踪器，这种设计方法可同时获得逆最优控制策略和自适应律，简单明了，仿真结果表明该控制算法的有效性，并给出了性能估计。

The conversion boundary of self-incompatibility was researched by sowing by stage. Sunshine of day and temperature was studied critically by investigating leafage and researching traits indoors. The results showed that the daily minimum temperature was the principal factor of affinity conversion and the affinity conversion boundary was 16.5~18.1℃.HE97 was primarily regard as self-incompatible line in this research. The method was by inbreeding and sib HE97, Half the silk of HE97 and Zheng58. Inbreeding and cross have been done simultaneously. The extending condition of pollen tube was observed by dying the silk after pollinating 4 hours. The individuals with pollen tube were observed having seeds, while the individuals without pollen tube were observed having few seeds or no seeds. So this study regard HE97 as sporophytic self-incompatibility .The planting ration of female parent HE97 and male parent 87-1 was 4:1.The nature cross-pollination was studied by the theory of endosperm xenity, the study show that the setting percentage of HE97 was 625%, in which the seed in self was 70% and the seed in hybrid was 30%. This was consistent with the study of silk anatomy structure, then come to the same conclusion: compatible pollen germination and fertilization can stimulate the self-incompatible pollen germination and fertilization in the same corn cob.

通过分期播种，进行了光温敏自交不亲和材料HE97亲和性转换区间的研究，依据田间跟踪调查叶龄及室内考种研究了HE97亲和性转换区间的光温临界值，结果表明：1日最低温度是影响HE97自交不亲和性的主要原因，亲和性转换区间在16.5℃～18.1℃之间。2通过HE97自交和姊妹交以及将HE97与郑58作为双亲，各自的花丝一分为二，分别正反交，授粉后4个小时分别取其花丝进行固定、染色，观察花粉管的伸长情况，根据结实率与花粉管伸长的对应关系，结果发现观察到花粉管的对应植株收获到了种子，而没有观察到花粉管的对应植株结实率极低或没有结实，本研究把HE97初步划为孢子体自交不亲和类型。3以HE97为母本，87-1为父本，按4母：1父行比，通过花粉直感效应研究天然异交率，结果母本HE97结实良好(62%)，其中自交粒占70%，异交粒占30%，结合花丝切片观察表明，亲和花粉的萌发及受精会导致落在同一果穗柱头上不亲和花粉的萌发不再受抑制。

A frame image of a video frequency sequence is read into a postpositional memory zone, and staring position and size information of a tracked object is obtained in the frame, then distribution statistical information of a target signature is extracted to build a gauss mixed model as an object template, a mean vector and a covariance matrix in gauss mixed distribution are used to describe the position and the size of the object, then the next frame image of the video frequency sequence is read into the postpositional memory zone. In a new frame video frequency image, a parameter estimation method is used to obtain object gauss mized model parameters in the current frame in iterative computation and find candidate template similar to the object template, and the final model parameters obtained in iteration are used to update the tracking window for realizing self-adaption of the tracked window.

将视频序列的一帧图像读入缓存区，获得该帧中被跟踪目标的初始位置和尺寸信息，然后提取目标特征的分布统计信息建立高斯混合模型作为目标模板，用高斯混合分布的均值向量和协方差矩阵描述目标的位置和尺寸，再将视频序列下一帧图像读入缓存区，在新一帧视频图像中利用参数估计方法迭代计算当前帧中目标高斯混合模型参数找到与目标模板最相似的候选模板，利用迭代得到的最终模型参数更新跟踪窗口实现跟踪窗宽的自适应。

Firstly, based on the sliding mode control and backstepping technique, a new attitude tracking controller is derived to control the attitude motion of spacecraft, the stability of the system is analyzed via Lyapunov method and the reaction wheel dynamics is also considered from the real applications point of view. The whole design process is divided into two steps: the first step is to use sliding control technique to design suppositional adaptive variable structure controller; and the second step is to design attitude tracking controller based on SMC and backstepping technique. Numerical simulations are performed to show that both tracking maneuver and vibration suppression can be accomplished effectively.

首先，采用自适应后步法结合主动振动控制技术设计了姿态跟踪鲁棒控制器，基于Lyapunov方法分析了系统的渐近稳定性；在此基础上，显性地考虑了执行机构动态特性问题，将整个设计过程分为两个步骤：第一步采用滑模控制技术设计了变结构虚拟控制器，给出自适应控制律的设计方法；第二步，将后步法与滑模控制技术相结合，设计了姿态跟踪鲁棒控制器，给出飞轮电压的输入算法及稳定性分析；最后，将提出的控制方法应用于挠性航天器的姿态跟踪控制，通过数值仿真对所提方法的可行性与有效性进行分析和验证。

Firstly, a class of affine nonlinear systems are considered. The single-layered neural networks are used to approximate the nonlinear functions of the systems. Stable adaptive control algorithms are presented based on system states feedback and system output feedback respectively. The boundary of the tracking error is guaranteed. Then, by using the technique of input-output linearization, the stable adaptive control method for general nonlinear systems is proposed. Finally, the effectiveness of the proposed adaptive control algorithms are verified through the simulation researches for the control of robot manipulator.

首先考虑一类仿射非线性系统，利用单层神经网络去逼近系统的非线性函数，分别给出了基于系统状态反馈和输出反馈的稳定自适应控制算法，确保系统的跟踪误差有界；然后利用输入输出线性化方法，给出广义非线性系统的自适应控制方法；最后通过在机械手位置跟踪控制中的仿真研究，验证了所提方法的有效性。

In allusion to weak point of traditional PID control can't effectively tracking parametric variation of control system ,utilize neural network have predominance that self-study、self-organization、associative memory、concurrent processing and can get satisfactory result in complex control system on the basis of double closed loop,advance apply adaptive linear element network—Adaline network, which has self-learn and self-adjust ability.

在双闭环控制的基础上，针对经典PID调节器不能有效跟踪控制系统参数变化过程这一弱点，利用神经网络具有自学习、自组织、联想记忆和并行处理等功能和对于复杂系统控制可以达到满意效果的优势，提出了采用具有自学习和自适应能力的单神经元网络——Adaline网络，来构成一种神经网络自校正控制器。

Through design, the text applying the parameter self-adjustable fuzzy PID controller to the position loop of servo system of radar, it has a kind very realistic meaning about improving the tracking speed and tracking precision, and completing the task of

将参数自整定模糊控制器应用到雷达伺服系统单脉冲跟踪位置回路的控制中，对于提高系统的跟踪速度和跟踪精度，实现对不同运动速度目标的测量，具有很好的现实意义。

In this paper, after researching various arithmetic of real-time tracking the author probe into these correlative tracking arithmetic and provide a new real time tracking arithmetic based on template self- correlation. It is a useful arithmetic that proved effective and feasible by series examination.

本文通过对各种实时跟踪算法进行研究后，针对相关跟踪算法进行了探讨，提出了基于模板自相关的实时跟踪算法，实验证明算法是有效和可行的。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失