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Controllable broadband reflection of cholesteric liquid crystal (N*-LC) materials has sparked enormous interests due to its significance in areas such as infrared shielding glass films and LC displ...

This paper studies the design scheme of valve hall fire protection trip logic, and gives the realization of valve hall fire protection trip logic. The realization process includes the dual design of the fire protection and disaster trip interface panel of the valve hall, and the development and design of the switching value acquisition device and the switching value trip interface device.The developed device has passed the third-party test of a testing research institute, and its performance meets the requirements of IEC standards It is not only applicable to UHV converter station, but also applicable to both conventional converter station and flexible DC converter station, providing reliable technical support for safe and stable operation of converter station.

This paper has done some research on how to economically optimize electrical collection systems containing the internal electrical network and the connecting parts to the grid of the offshore wind farm. First the paper summarizes the main factors that affect the economy of the offshore wind farm planning program and establishes the relationship flow graph used for the economic optimization. Then on the basis of the original economic optimization model and its special characteristics, the paper optimizes and solves the problem on its sub-regional levels using the combination of graph theory and the improved FCM algorithm. Finally an actual offshore wind farm presented in this paper proves that the large-scale offshore wind farm electrical collection system optimization method is fast and efficient. (5 pages)

A navigation algorithm completely based on machine vision for the autonomic landing of UAV without heading and attitude sensors is presented. The image of an airport runway lighting acquired by the airborne camera is determined by the aircraftpsilas attitude, heading and position relative to the runway. The image gradients of the centerline and threshold bar of runway lighting, the lognitudinal mean and the lateral mean of the image coordinates of the observed airport lights, etc., can be calculated and used as the measurements in a extended Kalman filter. The Kalman filter then generates the estimates of the aircraftpsilas motion parameters, including position and velocity relative to the ground, and attitude, heading and rotating rate. The simulation results indicate that the navigation algorithm meet the navigation accuracy requirements for various FAA categories of landing.

In this paper, a mean value test (MVT) is proposed to detect and isolate failures. Non-linear filtering is used to estimate the combinations of sensor errors affecting the parity vector, the estimates are used to form a compensated parity vector. The compensated parity vector is used to make an FDI decision for improving FDI performance. To illustrate its application, the MVT approach is used to detect and isolate the failure in an optimal mounting configuration of five single-degree-of-freedom sensors. Some results are obtained by comparing the MVT method with the generalized likelihood test (GLT) method. Simulation results prove that MVT method can detect and isolate the failure effectively when two sensors fail simultaneously.

An approach for multiple sensor faults diagnosis is presented. Fully-decoupled parity equations and parameters estimation are combined in this method. The residual generated from a fully-decoupled parity equation is sensitive to a special sensor fault and decoupled from all other sensor faults. The faults in sensors are represented as biases and changes in scale factor. A parameter estimator based on a Kalman filter is designed to identify biases and changes in scale factor from the information contained in the residuals. The fully-decoupled parity vectors, which are designed to detect and isolate sensor faults, are generated in various conditions, and their existence condition is given. A simulation example on a linear airplane model is given for illustration.

In this paper, a new method of detecting outlier in data is proposed. The new method is based on the identification of the ARMA model of system output. The outlier can be detected by a detection function. The recursive extended least-squares (RELS) method is used to identify the ARMA model of system output. Since the method is very sensitive to changes of coefficients of the ARMA model, an outlier can be detected quickly. Because the performance of Kalman filter will be deteriorated by the outlier, therefore, after the detection of the outlier, the residual of the Kalman filter is smoothed. Using this correction, the performance of the Kalman filter is improved. As an example of application, a simulation of guidance for semi-active radar homing missile is conducted. The result of the simulation proves that the outlier can be detected correctly, and the correction of Kalman filter is efficient and practical. >

In this paper, a new method of sensor failure detection and correction in flight control systems is proposed. The new method is based on the identification of CARMA model of system output. The recursive extended least-squares (RELS) is used to identify the CARMA model of system output. The value of the failure can be estimated by the modified RELS method. The new method was applied to the sensor failure detection and correction in flight control system. Simulation results based on a simplified longitudinal flight control system prove that the new method is practical. >