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The thesis illustrates the principle of the and its application in the system, establishes the simulation model of the vector control system of PMSM based on the EKF and successfully realizes the application of the speedless sensor in motor control. Firstly, based on the mathematic model of permanent-magnet synchronous motor, the PMSM vector control system is built. Secondly, the Extended Kalman Filter is designed for the on-line estimation of the speed and rotor position by only using measurements of the motor voltages and currents.

首先，基于PMSM的数学模型，建立了电机的矢量控制仿真模型；其次，设计了扩展卡尔曼滤波器，通过检测电机端电压、相电流对电机转速和转子位置进行在线实时估计，实现了PMSM的无传感器矢量控制；最后，在Matlab7.0环境下进行的系统仿真试验表明，该方法具有优良的转角跟踪特性和较好的转速跟踪特性，同时系统具有较强的抗负载扰动性能和较佳的控制性能。

In this paper, arrangement scheme of a novel multi-star phase shifted pole changing coil was given and the methods to determine coil split ratio were analyzed. According to electromagnetic theory, 2D electromagnetic mathematical model in which stator windings were spitted coil was developed, and magnetic field distribution of the novel motor at starting was solved by finite element method, starting performance of motor was calculated. Based on energy method, rotor slot leakage reactance under different poles and different loads were calculated, and the variation of rotor slot leakage reactance with loads was gotten. Based on time-step finite element method, distribution of branch current in stator windings and operating performance were calculated and analyzed when branch was unbalance, the method to calculate circulating loss in stator windings of novel multi-star phase shifted pole changing motor was given, and the effects of the loads variation and degree of unequilibrium on circulating loss in stator windings were calculated and analyzed.

论文系统的给出了采用分裂线圈法新型多星形移相变极绕组的排列方案，进一步分析线圈分裂比的确定方法；根据电磁场理论，建立了定子为分裂线圈绕组的电机二维电磁场数学模型，并采用场路耦合法求解了新型多星形移相变极电机起动时的磁场分布，计算了电机起动性能和基于能量法计算了不同极数下起动时转子槽漏抗和不同负载时转子槽漏抗，得出转子槽漏抗随负载变化的规律；采用时步有限元法计算分析了定子绕组支路不平衡时支路电流的分布情况及运行性能，给出了新型多星形移相变极电机定子绕组环流损耗的计算方法，分析比较了负载的变化和支路不平衡度大小对定子绕组环流损耗的影响。

In this paper, a procedure of nonlinear analysis of the cable-stayed bridge was developed based on the nonlinear theory of structures using the finite element method, in which the vehicle-bridge interaction element based on the concept of dynamic condensation is used. The influence of vehicles on the response of the cable-stayed bridge is studied by employing the spung mass model and the bridge model with and without considering cable vibration modes.

本文拟应用非线性力学分析程序与有限元素数值计算法，建立斜张桥的非线性分析程序，应用VBI的车桥互制元素配合动态浓缩的观念，以悬浮移动质量模拟车体对斜张桥的影响，并对考虑与不考虑缆索振动模态两种分析模型，做一对应分析比较。

Considering gas-solid flow in annular space and BoYun Guo's hydrodynamic parameters model, For aired underbalanced drilling, combined with the minimum energy Angel law and based on the mininum gas injection scale at the key points, it is established a bottom-hole pressure model for gas-solid two phase stream; meanwhile, calculated the downhole depth of the Downhole-Deployment-Valves; and then fabricated the corresponding calculation software. For streamingly underbalanced drilling, it is fully given a step-by-step solution based on analysis from the relationship of various wellbore pressures at the course of underbalanced drilling as well as from the streaming behavior in different wellbore sections, adding consideration on multiphase stream pressure drop and Downhole-Deployment- Valve into account, it is of common application for development wells.

对于气体欠平衡钻井，考虑环空为气固两相流，参考BoYun Guo的流体力学参数计算模型，结合Angel的最小动能法标准，从满足关键点处的最小注气量入手，建立了气固两相流的井底压力计算模型，同时对套管阀的下入深度进行了计算，并利用VB语言编制了相应的计算软件；对于液体欠平衡钻井，考虑环空为多相流，在充分分析欠平衡钻井井内基本压力关系的基础上，从环空多相流压降分析入手，通过对井筒内各段的流态分析，逐段求解。

The researching content was as follows: 1. When AlClx/HY zeolite be used as catalyst, the effects of the ratio of 2-methylnaphthalene to tetramethyl benzene, catalyst concentration, reaction temperature and reaction time on the conversion (based on 2-methylnaphthalene), yield and selectivity (both based on 2,6-DMN) were discussed. In addition, by orthogonal experiment, the optimum reaction conditions were determined at the same time. The optimum reaction conditions : the molar ratio of 2-methylnaphthalene and tetramethyl benzene =1:1, reaction temperature was 400℃.

具体研究如下： 1、以AlClx/HY型分子筛为催化剂，研究原料配比(2-甲基萘与均四甲苯的摩尔比)、反应温度和反应时间对2-甲基萘的转化率、目的产物2，6-DMN的收率和选择性的影响，并通过正交实验确定了该催化剂体系下的最佳反应条件为：原料的摩尔比为(2-甲基萘：均四甲苯)=1：1，反应质量空速为6h-1，反应温度为400℃。

The laboratory test on two-stage low-intensity magnetic separation and "medium- and low-intensity magnetic separation" technologies for the titanomagnetite was performed through selecting two-stage grinding-beneficiation technology based on -1.7mm coarse tailings abandoning. The results indicate that the technico-economic indexes of the two-stage beneficiation process based on "medium- and low-intensity magnetic separation" are better.

选择-1.7mm粗粒抛尾的两段磨选工艺对钛磁铁矿进行了二段弱磁和&中磁—弱磁&选别工艺的实验室试验，结果表明，&中磁—弱磁&二段选别工艺具有较好的技术经济指标。

Permanent magnet synchronous motor driven by triphase sinusoidal current is research object in this paper. On the basis of analysis of the structure, movement principle and math model of PMSM, Fundamental theories and structure of the system of PMSM alternating current servo systems based on DTC are discussed. Then Simulation models of traditional PMSM DTC and PMSM DTC based on vectors subdivision are established separately.

本文以三相正弦波驱动的永磁同步电机为研究对象，在分析永磁同步电机结构及数学模型的基础上，系统阐述了基于直接转矩控制的永磁同步电机交流伺服系统的基本原理和系统构成，并在MATLAB仿真环境下分别建立了传统直接转矩控制和基于矢量细分算法的直接转矩控制系统的仿真模型。

Through anaslysing section real constant and weight of different parts and selecting different element type which are based on structure blueprint, we will build the ANSYS model.2. Unloader boom will be discrete based on trolly travelling on it.

根据卸船机的金属结构设计图纸确定卸船机各个部件几何尺寸以及具体位置，通过分析不同部件的截面尺寸以及重量计算其相应的截面性质和材料密度，以及不同的结构部件采用其相应的单元类型，从而建立抓斗卸船机作业时的载荷变化与运行的在ANSYS中数学模型。

AIM: To study the compression performance of three-dimensional CT image based on region wavelet SPIHT algorithm, underlaying the previous researches on the compression coding algorithm of two-dimensional X-ray image based on SPIHT target area.

目的：在以往对二维X射线影像进行基于SPIHT的区域压缩编码算法研究的基础上，探讨基于目标区域小波SPIHT算法对三维CT图像的压缩方法。

This paper brings forward a approach for textile flaw automatic detection based on optimal Gabor filters. At first the niche genetic algorithm is employed to attain the parameters of the optimal Gabor filters and segmentation threshold based on the feature of the unflawed textile,and then apply the optimal Gabor filter and threshold on the fabric image to achieve the resnlts.

为了对织物缺陷进行快速准确的自动检测，建立了一种基于Gabor滤波器的织物缺陷自动检测方法，即首先根据无缺陷织物的结构特征，应用小生境遗传算法寻找最优的Gabor滤波器参数和分割阈值；然后将待检图像通过滤波和分割来得到检测结果，同时根据响应矩阵的极小值点来计算缺陷的形状特征。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。