Applied Mechanics and Materials Vols. 373-375

Abstract: Failure prediction is of great significance for power electronics systems. Taking the metro vehicle charger circuit as an example, soft failures are discussed. The paper established the system simulation model through MATLAB/SIMULINK, and carried on spectrum analysis with POWERGUI module, and analyzed system output when the parameter changed. With regard to charger circuit, the inductor should be replaced when the inductance drops to 1/2 of the normal. It is important for the on-site maintenance personnel to troubleshoot failures, improving the working reliability of metro vehicles.

Abstract: The purpose of this study was to examine the reliability of posturography using a newly developed automatic balance calibration system (I Balance S (CyberMedic Co., Korea)). Twenty-three patients who volunteered participated in this study. Mean center of gravity (COG) sway velocity, total distance, maximum velocity (MV), average movement degree (AMD), maximum excursion (ME) and directional control (DC) were measured by I Balance S. Overall stability index and overall directional control score were measured by Biodex Balance System (Biodex Medical Systems Inc., New York, USA). For the accurate measurement, the COG was automatically calibrated to zero before each measurement by I Balance S. Each subject was tested twice by examiner A and once by examiner B. The intraclass correlation coefficients (ICC) were calculated to assess the inter-rater and intra-rater reliability. Inter-rater reliabilities were higher with the I Balance S (ICC, 0.80-0.91) than with the Biodex Balance System (ICC, 0.71-0.82). Intra-rater reliabilities were similar between the I Balance S (ICC, 0.88-0.94) and the Biodex Balance System SD (ICC, 0.90-0.91). I Balance S using an automatic balance calibration system is a reliable posturography method for performing balance assessments.

Abstract: According to traffic jam problem in the tunnel, we study and design an analysis method of roadway transportation line which is suited of trackless tyred vehicle system underground coal mine, Through detailed analysis for traffic jam problem by trackless tyred vehicle in the tunnel, we designed automatic control algorithm for trackless tyred vehicle haulage system underground coal mine and designed the intelligent scheduling system, and solved the trackless tyred vehicles traffic problems.

Abstract: Automated control can improve the canal system to scheduler run levels, improve water efficiency and reduce operating costs schedule. In order to improve the accuracy and reliability of the control, the paper combines fuzzy control theory and PID control technology, Can give full play to the intelligence technology characteristics of the fuzzy control and can effectively improve the limitations of the traditional PID control, realize real-time self-tuning of PID control parameters, This ensures stable operation of drainage systems, can greatly improve the overall control performance of the canal, canal system automatic control development provides new ideas and approaches. Finally respectively for three kinds of operation mode of the single systems simulation, analysis of the superiority of the fuzzy theory combined with PID control.

Abstract: As the problem that loitering unit is vulnerable to stall because of air turbulence in the initial period of posture adjustment process, this paper is based on the classic flight control and the active-disturbance-rejection control principle, and uses the method of ADRC which based on RBF neural network. It designs the ADRC for the attitude adjustment of loitering unit in the initial period, and compares it with the classic flight control algorithm and the active-disturbance-rejection algorithm. Through the contrast of the control simulation for the three control algorithms we can obtain that, RBF ADRC is superior to ADRC control method and the classic flight control method.

Abstract: The article used the ATP-EMTP to study over-voltage condition of each device and propose the corresponding measures to limit over-voltage in a safe range, to ensure the security of the system and stable operation. The article has great means to the actual analysis of lighting disturbance.

Abstract: A new model based nonlinear iterative learning controller to replicate multiple reference trajectory is presented. The approach consists of a constrained Gauss-Newton numerical optimization algorithm, which is able to inverse a nonlinear system accurately. It uses the moving horizon idea from MPC to improve the computational efficiency. Combined with a class of nonlinear state-space model and an existing nonlinear iterative learning control scheme, this allows accurate tracking control of a nonlinear system. Numerical results are used to illustrate the algorithm.

Abstract: To eliminate the effects for section automatic cutting because of roadheader pose error, Control system of pose error compensation for roadheader was proposed. First, make the control strategy according to the coal mine actual working condition and the working ability of machine each actuator; Hardware system structure is proposed based on the control system and the corresponding sensors are installed; Last, according to the working way of roadheader, put forward the specific control methods of pitch attitude compensation control and cutting boundary compensation control. The above system has been tested on EBZ200 type roadheader and the testing results show that the system function is correct and reliable and the control precision is high. This system could eliminate the effects for section automatic cutting because of roadheader pose error efficiently and lays a foundation for remote control of roadheaders.

Abstract: In this paper, we introduced an effective time delay model for SRAM compiler, which represents an important performance of SRAM. Our method divide the delay time into several periods, including decoder delay, word line delay, bit line delay and SA delay. The theory is useful in predicting the delay time when the SRAM size is changed. Simulations by Hsim in 65nm CMOS process proves a high accuracy.

Abstract: High-impedance ground plane (HIGP) is applied in the design of rectangular waveguide end-slot phased array. The benefits of using such a HIGP are related to the suppression of surface waves because of its obvious frequency bandgap and, therefore, the scan blindness could be eliminated. Both of the bandgap curve of the HIGP structure and the scan properties of the phased arrays have been calculated. The elimination of scan blindness is obtained.