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Objective: This research aimed to investigate the curative effect of oblique lateral interbody fusion (OLIF) in the treatment of lumbar tuberculosis. Methods: A total of 32 patients, including 18 males and 14 females (29-58 years old, with the mean age of 47) who were admitted to our hospital from October 2016 to June 2020 and treated with oblique lateral interbody fusion combined with vertebral screw internal fixation, were retrospectively collected. The segmental distribution of lesions was L2- L316 cases, L3-L411 cases and L4-L55 cases. At first, preoperative antituberculous drug treatment was standardized for 2-4 weeks. Furthermore, intraoperative blood loss, operation time, postoperative complications, ESR, CRP, VAS, JOA and ASIA scores were recorded before and after surgery and at the last follow-up. In addition, antituberculous drug therapy was regulated continuously after surgery.Results: All patients were followed up for 12-17 months, with an average of 14 months. ① The average operation time was (132.5±21.4) min, and the intraoperative blood loss was (227.3±43.1) ml. ② Preoperative ESR was (74.56±15.43) mmol/h, and CRP was (43.21±19.37) mg/L. Seven days after surgery, ESR was (42.37±19.26) mmol/h, and CRP was (22.51±18.42) mg/L. In the last follow-up, ESR was (9.25±4.13) mmol/h, and CRP was (8.17±3.21) mg/L. They have statistically significant differences before surgery, seven days after the surgery and in the last follow-up (PConclusion: OLIF is a new minimally invasive method for treating lumbar tuberculosis, with short operation time, less blood loss, convenient operation, thorough removal of lesions, and good long-term follow-up effect. It is worthy of promotion and application.

In this paper, a novel sliding mode extremum seeking control (SMESC) scheme is proposed to improve the performance of the classic SMESC. In this scheme, the twisting sliding mode is employed to all...

Background. Staples closure technology has been widely used in total knee arthroplasty (TKA) and achieved good results. In recent years, a new type of material called skin closure tape (SCT) has been applied to TKA which also showed good treatment results. However, since it is still not clear yet which one is better, this paper collects literatures for statistical analysis so as to provide evidence for the use of SCT in TKA. Methods. The comparative study on effects between SCT and staples is reviewed after the primary release of TKA in PubMed, the Cochrane library, and the EMBASE database up to March 2019. The two researchers independently screened the literature and evaluated the quality of the literature using bias risk tools. Results. A total of four studies (3330 knees) have been included in our meta-analysis. For the main point, the results show that the SCT can reduce readmission rates compared to staples (RR 0.68, 95% CI 0.49–0.95, P=0.03), with no significant difference in complications (RR 0.85, 95% CI 0.27–2.64, P=0.77). Secondly, the results suggest that although there is no significant difference in removal time between the two groups, the SCT can reduce pains, save time and costs, and have a better cosmetic effect. Conclusions. Our study indicates SCT as a closure method with fewer complications and faster speed compared with staples. Nevertheless, the cost and pain need to be further confirmed because of the small sample size included in this study.

Aiming to online suppress the mechanical resonance existed generally in electromechanical servo system, this paper proposed an effective method based on extremum seeking control (ESC). Firstly, the theoretical analysis of 2-mass model with elastic load is carried out to obtain the mathematical expression and physical phenomenon of mechanical resonance. Then, a single variable ESC-based scheme is employed to identify the resonance frequency by introducing a band-pass filter with variable center frequency. Furthermore, based on the identified resonance frequency, the multivariable ESC is applied to design a parameter self-adjusting notch filter to suppress the resonance quickly online. In addition, an adaptive adjusting law of disturbance signal amplitude of ESC is designed to accelerate the convergence as well as eliminate the unexpected steady state oscillation existing in those parameters to be optimized. Finally, the effectiveness and superiority of this method are verified sufficiently by simulations.

The load change of flight simulation turntable often leads to the deviation of its control performance due to the poor adaptability of the traditional fixed-parameter controller for the varying model parameters. Aiming to identify the model parameters of flight simulation turntable precisely and rapidly and lay a solid foundation for the realization of adaptive controller with constantly high dynamic performance regardless of load alternation, this paper proposes an effective method based on dual extended Kalman filter (DEKF) to identify model parameters of turntable, in which, two low-order EKFs instead of one high-order EKF are used to reduce the computational complexity and improve the identification accuracy. And a parameter weighing approach is designed to overcome the enlarged error caused by differences in magnitude order among the parameters. Furthermore, simulations and experiments are conducted to verify the effectiveness and superiority of this method.

Aiming to increase the convergence speed of perturbation based extremum seeking control, this paper proposed a novel gradient-based perturbation extremum seeking control (GPESC) scheme by combining sine perturbation signal and input-output gradient. In this scheme, the demodulated output signal in classic extremum seeking control (CESC) is replaced with filtered input-output gradient signal to decrease the fluctuation of convergence, which can speed up the movement toward extremum dramatically. Strict stability analysis of GPESC is presented by using averaging method, and parameter selection principles are discussed. Moreover the effectiveness and superiority of the proposed scheme are verified with simulations.

Aiming to improve the frequency bandwidth of angular vibration table, this paper proposes a novel bandwidth extension scheme based on extremum seeking control (ESC). In this scheme, two perturbation extremum seeking controllers are employed to adjust the phase and amplitude of the sine input signal based on the extracted envelope of tracking error as the cost function of ESC to be minimized, for the purpose of compensating phase lag and amplitude decay of the system output. Furthermore, an adaptive amplitude adjusting method is designed with nonlinear transformation to accelerate the convergence as well as eliminate the unexpected steady-state oscillation existing in system output, which is caused by the perturbation signal of ESC. Consequently, the frequency bandwidth of the closed-loop system is extended greatly with the proposed scheme, which is verified sufficiently with simulations.