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For the characteristic of permanent magnet linear synchronous motor (PMLSM )that has no middle transmission links-the load connects to the motor active cell directly, the load resistance, the quality changes and the external disturbances directly influence the performances of the servo system, this paper uses a programme of self-tuning zero phase error tracking control (ZPETC ). The quality of active...
To develop image logging technology, this paper studies array magnetoacoustic tomography with magnetic induction(MAT-MI) on the basis of contrasting the research of home and abroad. Through design, computer simulation and experiment studies on generating system of pulsed magnetic field, we demonstrated that the pulsed power supply can realize narrow width, high peak and repeat pulsed current with...
The electronic information display console is an important device displaying integrated information on some type of large-scale ship. The human-computer interface (HCI) design that is not good enough will cause inefficiency or injury to the operators. If the deficiency is discovered while working, it will cost much labor, money and time. The virtual simulation method is tried to use evaluating the...
To calculate the temperature of 31kW submersible motor of YQY114P-2Series, established the three-dimensional mathematical model of stator and rotor considering that the temperature of the lubricate oil is changing. To got the temperature distribution in map through calculating the couple field of temperature field and fluid field by the method of Finite Element Method. And also we make the comparison...
This paper presents a method to determine the admissible set of controller parameters when the H-infinite norm of the mixed sensitivity is taken as the objective function for the PID controller design. First the mixed sensitivity requirement can be translated into the stabilization problem of a family of complex polynomials as well as the close-loop characteristic polynomial. Then by stabilizing these...
This paper builds the analytical force/torque-decomposing model of a multi-degree-of-freedom magnetically levitated stage with moving-coils by the plane integration of Lorenz Law based on the first harmonic model of Halbach Permanent Magnet Array and the surface current model of current-carrying coil. The test by multi-dimensional force sensor verified that the analytical force/torque-decomposing...
A two-stage data envelopment analysis (DEA) model is created to provide valuable managerial insights when assessing the dual impacts of operating and governmental strategies for the Science and Technology Activity Efficiency. This new model is used to analyze the inputs and outputs for the science and technology activity in the region and how to achieve efficiency systematically. In this paper, it...
Conventional SPIHT compression is for a 2D image or image block with the same maximum feasible decomposition level in two directions, so, only the size of image or image block is symmetrical, that is to say the maximum feasible decomposition level in two directions must be same and the image sizes had better be equal to 2level such as 32, 64, 128 etc, the optimal compression performance can be acquired...
Based on analyzing the situation of current underwater navigation, this paper presents an independent underwater navigation method, namely the terrain matching algorithm based on contour image. Firstly, according to multibeam bathymetric system data, the topographic contours are extracted out from the data and then form contour image. Secondly, the contour used for image matching is coded. The coding...
A tourism team is usually built up by tourists from different areas with different backgrounds and lifestyles, so that how to manage a tourism team has become a hot topic of current research. In order to solute this problem, we have designed a management system based on radio frequency identification technology which composes by tag reader and tans. The tag reader is carried by guider and the tags...
A high-voltage LED driver using Silicon-on-Insulator (SOI) technology is presented in this paper. The presented LED driver has a wide input range from 40V to 625V, and could be used in tens to a hundred series LED applications. This driver works in peak current control mode, which provides two dimming functions: linear dimming and PWM dimming. The output current requirement could be fulfilled by adjusting...
Single surface-driven progressive cavity pump (pcp) is mainly applied in viscous crude well and polymer flooding one. The liquid flowing in those wells complies with power law pattern. Well liquid in the annulus between the pumping rod and tubing of pcp well presents helical flow under the action of rapidly rotating pumping rod and pcp pressure difference. At present in most research, this flow was...
An Equivalent Current Injection (ECI) based Security-Constrained Optimal Power Flow (SCOPF) is presented in this paper and a Multiple Particle Swarm Optimization (MPSO) is developed for solving non-convex Optimal Power Flow problem. The OPF deals with both continuous and discrete control variables and is a mixed-integer OPF. The continuous control variables modeled are the active power output and...
Based on the motor machinery characteristic curve, establishes the dynamic model of the two-joint-motor machinery series system, completes the digital simulation no-load state to start driven by single-motor and two-joint-motor, analyses the elastic axis to adjust the size of the system stiffness and dual-motor mechanical properties differences to the system dynamic characteristics, compares the angular...
The aggregation of the topological neighbouring polygons developes well. There are some good algorithms, but the most are based on the topological spatial data model, it requests data build integrated topological relations. When the data is modified, we should vindicate the data's consistency, and it will cost so much time to rebuild the topological relations and even sometimes maybe failed. This...
This article built the simulation model between the catenary voltage and the traction motor based on the CRH2 high-speed EMUs, and aimed to analysis the impact on the operating speed of EMUs which is caused by the decreased catenary voltage.
Considered the effect of temperature on the main bearing, the temperature distributions of journal, bearing and lubricant were calculated, and the thermo hydrodynamic performances of the main bearing were analyzed by solving generalized Reynolds equation, energy equation and solid heat conduction equation, etc. The results show that the bearing has obvious effect on the temperature of lubricating...
Through analyzing the principle of unified power quality conditioner (UPQC), taking the left series-right parallel structure as example, the relationship of energy flow is analyzed. The power demand formulas of series side and parallel side are demonstrated and derived on this basis of minimum energy method. The selected principle of main circuit capacity is determined. Finally, experimental results...
Icing on overhead power transmission line is a serious problem that affects the secure operation of power system. This paper firstly analyses transmission line icing damage and the advantage & disadvantage of various current online monitoring techniques. Then, the implementation scheme of a novel method, which based on the sensor network of fiber optic sensor, is introduced. Through measuring...
In this paper, the method for solving laser beam quality factor M2 with normal equations is studied, and the numerical algorithm of solving the normal equations (NE) with triangular decomposition is presented at the same time. The normal equations method for solving laser beam quality factor M2 is consistent with singular value decomposition (SVD) method, but the first one is faster and more accurate...
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