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In order to alleviate the deterioration on control effect caused by the inertia mass and the time-delay of a rack and pinion electromagnetic actuator, a finite frequency dynamic output feedback H∞ time-delay control strategy is proposed in this article. Currently, a H∞ controller is generally designed with the objective to minimize the infinite norm of the transfer function from the external disturbance to the control output, and the values of the slack coefficients are obtained according to the experience. But when used in practical, problems are found that only small external disturbance energy and narrow scope of driving conditions are allowed and it is difficult to find the optimal solution just according to the experience. In allusion to these problems, a H∞ controller design method with the objective to maximize the allowable external disturbance energy is proposed, and genetic algorithm is used to optimize the values of the slack coefficients. Finally, bench tests are carried forward to verify the control effects of the two controllers. The tests results show that, the controller designed with the objective to maximize the allowable external disturbance energy can adapt to more severe driving conditions, and it is more significant in actual application on vehicles.

Electromagnetic actuator has many advantages such as fast response speed and good controllability, and can achieve energy from suspension system's vibration when it works in the generator state. Electromagnetic actuator which is designed in this paper not only has the characteristics of good impact resistance and stable output and also can effectively achieve the energy which is generated by vibration of suspension system. However, it's difficult to control electromagnetic damping force which seriously affects smooth running of the vehicle. So a wireless energy transmission method based on self-excited resonance is proposed. Using paralleled magnetic rheological damper to compose composite damper, which solves the failure safety problem of suspension system and realize the accurate control of damping force when achieve vibration energy produced by suspension system. Theoretical analysis and bench test show that the designed wireless energy-regenerative electromagnetic actuator has strong technical advantages and has high application value.

In order to improve suspension vibration attenuation performance and recover the suspension vibration energy, a pinion and rack-type electromagnetic actuator with the ability of active control and energy-regenerative is designed. The inertia force of the rotating motor of electromagnetic actuator in the reciprocating motion will affect the damping and amplitude frequency characteristics of suspension. Based on the two-degree-of-freedom suspension dynamics model of a quarter vehicles, firstly, the inertia mass of the electromagnetic actuator is calculated theoretically. Then, the force of electromagnetism actuator under the condition of with motor and without motor are tested respectively, the inertia mass value is calculated and the theoretical value is verified. Finally, the influence of inertia mass on electromagnetic suspension damping and amplitude frequency characteristics is analyzed. The results show that the inertia mass measured is 18.93 kg, and the error is about 13.49% with the theoretical value of 16.68kg. Inertia mass makes the damping produce hysteresis loop, which improves the amplitude and frequency characteristics of suspension at low frequency while deteriorates at high frequency. At the same time, inertia mass will bring forward the common vibration point. Therefore, EA should be made to work in the middle and low frequency bands.

Objective To evaluate the outcomes of selective uterine artery embolization (SUAE) in treatment of symptomatic uterine fibroids using Color Doppler ultrasonography (CDUS). Methods As the procedure SUAE for fibroids, prospective data of the initial 65 consecutive women treated from March 2007 to September 2009 were collected. The follow-up period from 1 week to 30 months, using questionnaires, we investigated the fibroid-related physical and psychological symptoms, and the cumulative rates of symptom control, gynecologic interventions, and complications. The volumes of uterine and uterine fibroids were calculated by CDUS pre- and post-SUAE for 6 months. And we tested the levels of internal hormone including FSH, LH and E2 before and after SUAE for 3, 6 months. Results SUAE was performed successfully in all patients. There was no peri-operative morbidity in all procedures. Compared with pre-SUAE volumes of uterine [(322±112) cm3] and uterine fibroids [(125±46) cm3], their volumes in post-SUAE were (144±72) cm3 and (51±11) cm3 (P 0.05). After SUAE for 24 months, the fibroids related physical and psychological symptoms such as bleeding, pain and quality of life were significantly improved (P Conclusion SUAE contributes to a long-term significant improvement of all investigated uterine fibroid-related symptoms and markedly improves women's health-related quality of life. SUAE that no impair on changes of internal hormone, under suitable conditions, represents an attractive alternative to hysterectomy for the treatment of symptomatic fibroids and is a minimally invasive, new method of good clinical prognosis. CDUS is an effective to investigate the outcome of SUAE.

To realize the target of shifting gears rapidly and smoothly, the paper puts forward a kind of pneumatic AMT control device design project in allusion to a certain type of tracked armored vehicles' structure characteristics. According to the project, the paper has a refit on the tracked armored vehicle and conducts a test, it is verified that the new designed device works stably and reliably, achieves the target to shift gears at a high pressure, keep the gear at a low pressure and shift gears in a short time, well satisfies the request of the vehicle's automatic transmission system.