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Bai S.,Chengdu Electromechanical College
Taiyangneng Xuebao/Acta Energiae Solaris Sinica | Year: 2014

A new structure of photovoltaic inverter with Luo-Boost circuit and three-phase four-switch units was proposed to improve the efficiency of photovoltaic power generation and reduce the cost of photovoltaic systems effectively. Accordingly, a new feedforward power predictive control strategy was brought out, which would determine the related predictive value of feedforward power through the partition and arrangement of the natural environment conditions, and then the optimization of its historical largest photovoltaic power. With small amount of calculation, fast speed, simple, high precision and reliability, the new control strategy can leave out the traditional inverter DC voltage control loop and complete the MPPT function of the photovoltaic inverter itself, so as to enhance system response speed and reliability. Both simulation and experimental results both verified the feasibility and advantage of proposed structure and control method.

Mu D.,Sichuan University | Mu D.,Chengdu Electromechanical College | Shen B.-l.,Sichuan University
International Journal of Refractory Metals and Hard Materials | Year: 2010

Boronizing of CoCrMo alloy has been performed by means of a powder-pack method using commercial LSB powders at 850, 900 and 950 °C for 8 h, respectively. In this study, the boronized CoCrMo alloy before and after oxidation tests were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The distribution of alloy elements of boronized samples from surface to interior was determined using energy-dispersive X-ray spectroscopy (EDS). XRD study showed the boride layer formed at 950 °C/8 h consisted of the phases Co2B and CrB. Depending on boronizing temperature, the thickness of boride layer ranged from 2 to 11 μm. Cyclic oxidation behavior of the boride layer has been investigated at an oxidation temperature of 950 °C with a total exposure time up to 50 h in air. The test results indicated that the boronized CoCrMo alloy had superior oxidation resistance compared to unboronized sample. © 2010 Elsevier Ltd. All rights reserved.

Mu D.,Sichuan University | Mu D.,Chengdu Electromechanical College | Shen B.-L.,Sichuan University | Zhao X.,Civil Aviation Flight University of China
Materials and Design | Year: 2010

In this study, CoCrMo alloy was boronized at 950°C for 2, 4, 6 and 8h, respectively. The boronized samples were characterized by scanning electron microscopy, X-ray diffraction, microhardness tester and ring-on-block wear tester. X-ray diffraction studies showed the boride layer formed at 950°C for 2-8h consisted of the phases Co2B and CrB. A large number of pores formed in diffusion zone were probably attributed to the Kirkendall effect. Depending on boronizing time, the thickness of boride layer ranged from 4 to 11μm. The excellent wear resistance of the boronized CoCrMo alloy was attributed to the high surface hardness of the Co2B and CrB under dry-sliding conditions when compared to the as-received state. © 2010 Elsevier Ltd.

Wang Q.,Chengdu Electromechanical College
2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011 | Year: 2011

The complexity and the nonlinear characteristics of Highway traffic incident, this paper presents a detection method based on Artificial Neural Network, designs AID algorithm based on testing facilities, simulation results show that BP algorithm has the advantages of high detection rate, low false alarm rate and short detection time after comparing with traditional algorithm. But there are also shortcomings to make further research. © 2011 IEEE.

Tang T.,Chengdu Electromechanical College
Proceedings - International Conference on Natural Computation | Year: 2012

Image-based and minutiae-based are two major methods of fingerprint recognition. In this work, we presented an image-based fingerprint recognition method by using wavelet transformation and this method is efficient even for low quality fingerprint. The features extraction of the proposed method differing with previous wavelet methods is based on the blocks of enhanced region of interest (ROI). The alignment is required to build ROI including location the reference point and rotation alignment. Fingerprint matching was performed on simply Euclidian distance of feature vector extracted from wavelet domain. These features consist of mean energy, standard deviation and Shannon entropy for the purpose of making these features more discriminative. The good recognition accuracy was achieved on the FVC2002 database. © 2012 IEEE.

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