Advanced Materials Research Vol. 823

Abstract: For the multi-time scale characteristics of vibration signal, a composite multi-frequency dictionary combining the low-frequency Fourier dictionary and the high-frequency impulse time-frequency dictionary is constituted, to decompose multi-component vibration signal into the combination of several one-component signals. The use of empirical model decomposition (EDM) in high-frequency impulse Component signal including feature information is to realize segmented Hilbert-Huang transform of signal and to acquire the time-frequency representation of every one-component signal, which is the process of fault information extraction of vibration signal. The application of the method in main reducer fault diagnosis verifies the engineering practicability and validity of the new algorithm.

Abstract: White noise deconvolution or input white noise estimation has a wide range of applications including oil seismic exploration, communication, signal processing, and state estimation. A globally optimal weighted fusion white noise deconvolution estimator is presented for the multisensor linear discrete systems using the Kalman filtering method. It is derived from the centralized fusion white noise deconvolution estimator so that it is identical to the centralized fuser, i.e. it has the global optimality. Compared with the existing globally suboptimal distributed fusion white noise estimators, the proposed white noise fuser is given based on the local Kalman predictors, and the computation of complex covariance matrices is avoided. A simulation for the Bernoulli-Gaussian input white noise shows the effectiveness of the proposed results.

Abstract: Based on the real requirements of ship navigation training simulation, a method of integration of AIS and ship navigation training simulation system was presented. The component and function of ship navigation training simulation system was introduced at first. And then the type and format of AIS information is analyzed. The AIS information simulation method is illuminated, the AIS information is send through serial port by the coach console, the AIS information is simulated by coach commander based on the receive message of AIS. The test result shows that the method presented in this paper can meet the requirements of integration of AIS and ship navigation training simulation system, and can also be able to satisfy the training demand of crews onboard.

Abstract: To address the PID parameter tuning problem, inspired by the swarm intelligence optimization algorithm, a tuning method of PID parameters based on particle swarm algorithm is proposed. To find an optimal set of PID control parameters in the target space, three parameters of the PID are as particles based on the fitness function. By designing optimization programs, air-conditioning temperature control system experiments were carried out as an example. The results show that the optimization can improve the dynamic control performance of the system.

Abstract: This paper makes a research on multiple UAVs task allocation in cooperative combat. The control target is presented and the model is built of the problem. By introducing load factor, the traditional task allocation algorithm based on contract net is improved. With considering the mission capability of UAVs, a task allocation algorithm based on improved contract net is given. The improved algorithm can significantly reduce the communication between UAVs, and can optimize the task allocation process. The simulation results show that compared with the traditional task allocation algorithm based on contract net, the improved algorithm can improve the efficiency of UAVs task allocation and balance the task load between the UAVs, it can solve the problem of multiple types of tasks allocation effectively.

Abstract: With the rapidly growing of passenger flow in big city, Communications Based Train Control (CBTC) system is believed to be the chief choice for urban railway transportation system. Interlocking system is a key safety critical application for CBTC, as it provides trains safety routes both in normal condition and under degraded mode. To deal with the logic complexity and high demand for safety, this paper addresses a novel scheme for modeling and realization of CBTC interlocking system. Using SCADE toolset, core function model prototypes are elaborated and software codes are generated automatically. The practical application indicates that this method provides an accurate and complete description for the whole system, and offers a path to gain high quality system implementation.

Abstract: A method of Rotating Machinery fault feature extraction based on wavelet transform and Hilbert demodulation is been studied. On the basis of rotating machinery fault mechanism and spectral characteristics, wavelet transform is used to be decompose the vibration acceleration signals of bearing faults into different frequency bands, Which is then used to achieve accurate fault information by Hilbert demodulation. The result shows the method can effectively improve the frequency resolution and realize accurate extraction of fault feature, and it has certain practical value for industrial production of rotating machinery faults diagnosis when applied to the production industry. Key words: Rotating Machinery; bearings; Wavelet algorithm; Hilbert demodulation

Abstract: The guided-wave technology is very efficient in inspecting a large portion of pipe. In order to study the propagation property of guided wave in pipe and the interaction between guided waves and defects, pipe model was established using 3D solid finite element in the software ANSYS. Tangential displacements were prescribed on the nodes in the pipe end and the propagating of T(0,1) mode guided wave in pipes was simulated. The detecting signals for the pipe model with different defects were extracted, which matched very well with experimental result.

Abstract: The ash storage is indispensable equipment in the coal-fired power plant, it used to store coal ash. The accurate measurement of coal ash level in the storage can ensure the boiler ash discharge smoothly. But the ash level measurement problems with dust, low dielectric constant, negative / positive pressure and long measuring distance (up to 70 m) etc., resulting in material level measurement becomes a major difficulty in level measurement technology. This paper puts forward a kind of mechanical measurement methodHeavy hammer-level meter detection based on investigation and research around the Hubei power plant. Practice has proved that this measurement method has the advantage of high measuring accuracy, little maintenance, great economic value and it can reduce the maintenance cost of power plant. At the same time this paper also provides some basis for the other studies on continuous measurement of material level.

Abstract: The paper introduces a new low-cost temperature measurement solution. CTMU module is available in many Microchip microcontrollers.The method is to use the CTMU of microcontroller and a diode to replace the higher cost thermostat or temperature sensor.