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Context Current medicine for Alzheimer's disease (AD) cannot effectively reverse or block nerve injury. Traditional Chinese Medicine practice and research imply Aconiti lateralis Radix Praeparata (Fuzi) may meet this goal. Objective Analysing the anti-AD effect of Fuzi and its potential molecular mechanism. Materials and methods AD model cells were treated with Fuzi in 0-300 mg/mL for 24 h in 37 °C. The cell viability (CV) and length of cell projections (LCP) for each group were observed, analysed, and standardised using control as a baseline (CVs and LCPs). The Fuzi and AD relevant genes were identified basing on databases, and the molecular mechanism of Fuzi anti-AD was predicted by network analysis. Results Experiment results showed that Fuzi in 0.4 mg/mL boosted LCP (LCPs = 1.2533, p ≤ 0.05), and in 1.6-100 mg/mL increased CV (CVs from 1.1673 to 1.3321, p ≤ 0.05). Bioinformatics analysis found 17 Fuzi target genes (relevant scores ≥ 20), showing strong AD relevant signals (RMS_p ≤ 0.05, related scores ≥ 5), enriched in the pathways regulating axon growth, synaptic plasticity, cell survival, proliferation, apoptosis, and death (p ≤ 0.05). Especially, GRIN1 and MAPK1 interacted with APP protein and located in the key point of the "Alzheimer's disease" pathway. Discussion and conclusions These results suggest that Fuzi may have therapeutic and prevention potential in AD, and GRIN1 and MAPK1 may be the core of the pathways of the Fuzi anti-AD process. Fuzi should be studied more extensively, especially for the prevention of AD.

A sliding mode robust control based on HJI theory is proposed for the synchronous control of the H-type precision motion platform driven by the dual linear motors. Although the same control method is operating on two Permanent Magnet Linear Synchronous Motors (PMLSM) with identical parameters. The synchronous error between the two motors is unavoidable due to the unbalanced forces, mechanical assembly variations, and various disturbances during the working process. The synchronous error will affect the quality of the workpieces and even lead to a stop of the working process due to over current protection. In this paper, the dynamic model of single-axis motion control system with a lumped uncertainty, which comprises parameter variations, external disturbances, and nonlinear friction force, is introduced first. The sliding mode robust control based on HJI theory is proposed for the single axis of the H-type precision motion platform, by designing the Lyapunov function and the sliding mode control law of the control system to satisfy the HJI theory, so that the robust condition is guaranteed. It can be concluded from simulation results, sliding mode robust control based on HJI theory can improve the tracking accuracy of the single axis and ensure synchronous error converge to zero. This indicates that tracking performance and robustness of the system is improved.

An interval type-2 fuzzy neural network(IT2FNN) control method is presented for H-type gantry stage driven by dual linear motors. The synchronous motion of the dual linear motors is the main factor affecting the accuracy and robustness of the servo system. Thus, the proposed method sets the position error of the both side motors as input, the powerful self-learning ability of neural network is used to guarantee the synchronous error converge to zero to achieve synchronous control. From the simulation results, the synchronous performance of the two-axis motion is significantly improved, and the robustness can be obtained as well using the proposed IT2FNN control method.

Dynamic surface backstepping sliding mode position control method of permanent magnet linear synchronous motor (PMLSM) was presented in this paper. The influence of uncertainties such as parameter variations, load disturbances, end effect and friction, on the performance of PMLSM was considered. Based on the mathematical model of PMLSM and backstepping sliding mode theory, the position controller was designed by combining the backstepping design method and sliding mode control. The concept of virtual command was introduced. There is a weakness in backstepping method that is a complexity of control law caused by achieving the derivation of the virtual control. Dynamic surface control method solved this problem by calculating the derivative of the virtual control using the first-order integral filter. The stability analysis of the controller of PMLSM was achieved by Lyapunov function. Simulation results show that the influence on system performance of uncertainties can be effectively restrained. The design of controller and parameters were simple and the proposed controller ensured the robustness and tracking speed of PMLSM control system. The chattering phenomenon of sliding mode control has been effectively suppressed.

The research shows that the increase of the strength of reinforcing bars can effectively improve the bearing capacity of the components, reduce the amount of reinforcing bars and decrease the difficulty of construction. At present, the yield strength of high-performance reinforcing bars developed abroad and applied in practical engineering is 400–900 MPa, while that in China has reached 700 MPa. As strain-rate sensitive materials, the strain-rate effect of reinforcing bars should be taken into account in the design of seismic buildings and explosion-resistant protective structures. In order to figure out the strain-rate effect of HTRB700, the properties of HRB400 and HTRB700 reinforcing bars are tested. Their performance mechanism and strain-rate response are studied respectively. Among them, the strain rate range of strain-rate effect experiments is 2.5×10−4–100 s−1. The calculation formula is obtained after fitting and analyzing the experimental results, which provides information for the popularization and application of HTRB700 reinforcing bars with new high strength and high plasticity in seismic and explosion resistant structures.

We present a laser frequency locking to Rydberg transition with electromagnetically induced transparency (EIT) spectra in a room-temperature cesium vapor cell. Cesium levels 6S1/2, 6P3/2, and the nD5/2 state, compose a cascade three-level system, where a coupling laser drives Rydberg transition, and probe laser detects the EIT signal. The error signal, obtained by demodulating the EIT signal, is used to lock the coupling laser frequency to Rydberg transition. The laser frequency fluctuation, ~0.7 MHz, is obtained after locking on, with the minimum Allan variance to be 8.9 × 10−11. This kind of locking method can be used to stabilize the laser frequency to the excited transition.

Considering nonlinear and uncertainty of the system and complex contour error model, in order to improve contour machining precision, a global fast terminal sliding mode control based on equivalent errors method was proposed. Nonlinear equivalent errors model of direct drive XY table by permanent magnet linear synchronous motor(PMLSM), which is easily calculated, was built by using equivalent errors method. Direct drive XY table contour controller was designed by global fast terminal sliding mode method. The method can make the states of the system converge fast to the equilibrium point in finite time and reduce the affect of load disturbance and uncertainty of the system. The simulation results show that the designed contour controller can make the system of direct drive XY table have high contour machining precision and strong robustness.

Contour control is an effective method of providing precision machine tool control, and various methods have been proposed to date. A novel design method based on cross coupled control (CCC) with the position error compensator (PEC) was proposed in this paper. According to the real-time contour error, current feedrate and tracking dynamics of each axis, PEC compensated the position error. The integrated control scheme is used to improve the contour precision and anti-interference performance. The fuzzy-logic-based feedrate regulator is used to adaptively adjust the feedrate. The proposed approach can simultaneously improve tracking performances and contour precision without complex controllers. Simulation results indicate that the strategy can reduce the contour error efficiently.

With the rapid development of the theory and application of artificial neural network, it has been widely used in the science of engineering, management, medical, society, education or more, and had great impact on many fields. This paper deals with the graduation project quality evaluation by using artificial neural network technology. This new evaluation model could overcome some disadvantages of traditional evaluation methods; gain a more scientific, objective and high-efficiency result.

In order to improve the contour machining precision in linear servo system, a novel design strategy based on cross coupled control (CCC) with the position error compensator (PEC) was proposed in this paper. According to the real-time contour error, current feedrate and tracking dynamics of each axis, PEC compensated the position error. Combined with the traditional CCC, it can improve the contour precision and anti-interference performance. The main advantage of the proposed approach is that it can simultaneously improve tracking performances and contour precision without the design of complex controllers. Simulation results showed that the strategy can reduce the contour error efficiently.

The synchrodrive is the important part in the gantry moving type milling machining centers. First, robust compensation are designed for linear servo systems with parameter variations, friction disturbance and no linearity at low speed. Then, a synchronization control strategy is presented based on fuzzy-coordinated control according to the double position synchronized drive of numerical control (NC) gantry-moving type milling machining centers. By the designed fuzzy-coordinated controller between the two synchro-driven passages, the output error between two synchro-driven systems is overcome. And the purpose of synchronization control could be realized. The simulation results show that the proposed scheme have both high synchronization accurate and strong robustness, and while low speed the demand of synchro-driven of NC machining centers can be satisfied.

The levitation rigidity for the levitated crossbeam of the gantry numerical control machine tool which can eliminate friction and increase machining precision is discussed. The feedback linearization and sliding mode control methods are presented in this paper in order to achieve steady levitation. The nonlinear electromagnetic levitation system is transformed into linear system by using feedback linearization method. The sliding mode control method is adopted for improving the robustness of the levitation system. Simulation results show that the system has more powerful ability of suppressing disturbance and high rigidity compared with that using conventional PI control method.

A synchrodrive scheme for gantry moving type milling machine driven by dual permanent magnet linear synchronous motors (PMLSM) is presented in this paper. The decoupling control and the proposed two-degree-of-freedom (2-DOF) internal model control (IMC) scheme are applied to the position servo system to counteract the influence of mechanical coupling rapidly, guarantee high response ability for the reference signals, high restraint ability for the model perturbations and the external disturbance, and then meet dynamic synchronized performance in machining. The simulation is completed by using MATLAB software, and the results show that the proposed scheme has both rapid response and strong robustness, and the demand for the high precision synchronization control can be satisfied.

The paper discussed an adaptive friction compensation scheme based on Coulomb friction and a parameter identifier. The model reference adaptive system based on Coulomb friction was designed to compensate the friction on-line. The designed model reference adaptive parameter identifier was combined with the adaptive friction compensation system and the mover mass was identified by the parameter identifier to update mover mass in the model reference adaptive control system based on Coulomb friction. Simulation results show that the position tracking precision of system and robustness were improved.

Self-constructing feedback fuzzy neural network controller (SCFFNNC) is designed to aim at the parameter uncertainties for permanent magnet linear synchronous motor (PMLSM) since they cause negative influence to the dynamic performance of PMLSM servo system. The thought about self-constructing, in which the number of neurons for the whole structure can be able to increase on line according to the variety of error, is introduced based on combining the non-linear identification of fuzzy control with self-learning of neural network. It can reserve the self-learning abilities, improve the real-time performance for neural network and then enhance the dynamic performance of PMLSM. The simulation results show that the servo system for PMLSM based on SCFFNNC can realize quick response, high precision and strong robustness for the parameter uncertainties of PMLSM.

For the electromagnetic suspension unit, a robust two-degree-of-freedom (2-DOF) control strategy based on combining feedforward control and Hinfin control is investigated in this paper. The control scheme solves the conflict between accurate command tracking performance and disturbance rejection of the system. The feedforward controller is designed to ensure that the system implements accurate tracking performance. While Hinfin controller can overcome the influences of the uncertainties of parameter perturbations and external load disturbances, achieve stability and robustness. The simulation results show that the control scheme not only can ensure system strong robustness to parameter uncertainty and load disturbances, but also improve accurate tracking performance.

The paper presents a nonlinear L2 robust control method for permanent magnet linear synchronous motor (PMLSM) drive system. Firstly, the nonlinear mathematical model of the motor is set up, and then a L2 robust controller is given by properly defined storage functions which are designed by back-stepping method. Furthermore, the L2 robust controller is shown to achieve the disturbance attenuation and the asymptotic stability based on the controller. Simulation analysis is processed. Simulation results show the system with the L2 robust controller can guarantee the good disturbance attenuation as well as the tracks of input signal, and can finally enhance control requirement for high-performance servo system.

This paper presents a speed controller for an interior permanent magnet synchronous motor (IPMSM) based on adaptive backstepping method. By using the nonlinear model of IPMSM and backstepping method, the Lyapunov functions are constructed in order to enable the system to have uniformly asymptotic stability and unperturbed controller is designed successfully by adopting the gradual correcting algorithm. The simulation is completed by using MATLAB software. The simulation results show that the designed feedback controller make the close-loop system stable and has better tracking performance.

This paper presents a H/sub /spl infin// speed controller based on internal model theory. The output point mixed sensitivity method is adopted to restrain the disturbance of servo system and guarantee the robust stability. A proximate internal model is introduced into disturbance path when solving the standard H/sub /spl infin// control problem. It can simplify the design and satisfy the requirement of servo performance. A H/sub /spl infin// load disturbance observer is designed which achieves the disturbance cancellation and guarantees robust stability. Simulation results show that the system has improved performance by the methods proposed in this paper.

This paper presents an implementation of zero speed sensorless control for permanent magnet synchronous machines (PMSM). The paper focuses on the principles and practical implementation of high frequency injection technology in a salient PMSM. The method using rotating vector, carrier frequency excitation and heterodyning, tracking observers for position estimation is discussed. A DSP-based drive system for this purpose is developed The experimental results for the case of a buried PM machine are shown in the paper. It was demonstrated that acceptable results could be obtained from the buried PM machine using the simplest, single saliency-tracking method and a digital solution (DSP system based) is feasible for low speed operation, including zero speed.

This paper describes a high performance fully digital implementation of a permanent magnet synchronous motor (PMSM) servo system. On the basis of the vector control principle, the system is controlled by an INTEL 8031 microprocessor and a TMS320C25 DSP chip. A new self-tuning PID algorithm based on LATE optimal rule is used in the speed loop. The experimental result demonstrates that the system is capable to improve the performance in terms of precision of control action, dynamic response and flexibility, even when the system parameters are varied.

This paper describes an easy-to-use interface software for the analysis of steady-state characteristics of stepping motor. It is capable of performing the simulation of stepping motor characteristics with various drive circuits and various parameters. The interactive software package has been implemented in a personal computer. It is made in Visual Basic based on a Windows environment and can be used universally by drives engineers. The simulation of steady-state characteristics of a stepping motor and results are presented in detail. Experimental results show that it fills the need for an interactive simulation to assess the influence of various motors drive circuits and parameters on the operating performance of stepping motor.

This paper describes a DSP-based neural network controller of a high-performance brushless DC servomotor system. It has a multi-layer feedforward structure and adopts a DSP (TMS320C30) as its operation element. Its learning scheme and design method are discussed. Simulation and experiment results are presented and the performance of such neural network controllers is studied.

Rotor position detection is necessary for phase commutation and current control in high performance PMSM. Traditional detection methods are based on resolver, absolute encoder etc. The paper presents a position and velocity sensorless control algorithm based on a direct neural model reference adaptive observer. The proposed observer comprises two neural networks which are trained to learn electrical and mechanical models respectively. By using current prediction error, adaptation is realized by new fast orthogonal triangular decomposition based RLS training method. Various advantages of this estimating scheme over other sensorless control scheme, such as robustness, nonlinear adaptation and learning ability is shown by extensive simulations.

The paper proposes a new position control strategy which is robust against load disturbance, torque ripple and parameter variations. The strategy is an expansion of disturbance observer based on acceleration control loop. According to the current and position information, the disturbance observer estimates the disturbance and parameter variations and constructs the feedforward force loop. As a robust control system based on disturbance observer sometimes has high overshoot and oscillated response, both the feedback controller and disturbance observer adopt fuzzy variable structure construction so that observer noise is suppressed. The effectiveness of the proposed controller is verified by experimental result. Disturbance suppression and improvement of phase delay are attained.