Xie Z.,Gui Zhou Normal University |
Zheng J.,Gui Zhou Normal University |
Quan B.,Gui Zhou University
Advanced Materials Research | Year: 2010
In this paper, parameter optimization of the electrical discharge machining process to Ti-6Al-4V alloy considering the multiple responses using the Taguchi method and grey relational analysis is reported. The multi-response optimization of the process parameters are material removal rate (MRR) and electrode wear rate (EWR). The machining parameters including discharge current, voltage, pulse on time and duty factor. Experiment based on the orthogonal array, The optimized process parameters simultaneously leading to a lower electrode wear ratio and higher material removal rate are then verified through a confirmation experiment. The experimental result for the optimal setting shows that there is considerable improvement in the process. The validation experiments show an improved electrode wear ratio of 2.8%, material removal rate of 45.8% when the Taguchi method and grey relational analysis are used. © (2010) Trans Tech Publications.
Chen T.Y.,South China University of Technology |
Chen T.Y.,Gui Zhou University |
Li W.F.,South China University of Technology |
Jun J.D.,South China University of Technology |
And 2 more authors.
Materials Science and Technology | Year: 2010
With the aim to synthesise well proportioned disperse poly(vinyl chloride) (PVC)/nanometre calcium carbonate (nano-CaCO3) composites, the authors used emulsifier tx10 polyoxyethylene octylphenol ether to prepare emulsion liquid for modifying nano-CaCO3. Let nano-CaCO3 well proportionedly disperse into the water, the authors created a new method for the characterisation of emulsion liquid and use the emulsion to synthesise PVC/nano-CaCO3 composite. The microstructure, particle size distribution and thermal properties of composite were respectively evaluated by TEM, laser particle size analyser and thermogravimetry analysis tests. The results showed that nano-CaCO3 were uniformly distributed in the PVC with 5.2 wt-%. Compared with the pristine PVC, the particle size distribution of the composite is more uniform and the thermal stability increases. © 2010 Maney Publishing.
Peng X.,Gui Zhou University |
Qian J.,Gui Zhou University |
Zhang B.,International Power |
Peng R.,De Zhou Vocational and Technical College
Applied Mechanics and Materials | Year: 2012
Oil whip, which is one of the typical types of steam turbine failure, may lead to large amplitude vibration of the rotor and even to catastrophic accident. in order to prevent and on-line eliminate the oil whip, researches on vibration of steam turbine caused by the oil whip and its characteristics have been elaborated from two respects of theory and experiment. the causes and the formation mechanism of the oil whip have been analyzed, and in certain conditions, a series of experiments for the oil whip on the rotor experiment rig have been made. illustrating and summarizing the results of these experiments by change the rotor speed and the lubricant quantity. these researches on the oil whip could provide some theoretical bases for the practical work. along with the expounded prevention measures of oil whip, some ideas on oil whip online elimination are put forward. ©(2012) trans tech publications, Switzerland. © (2012) Trans Tech Publications, Switzerland.
Lan S.,Gui zhou University |
Chaohui J.,Gui zhou University
International Journal of Digital Content Technology and its Applications | Year: 2012
Based on structure characteristics and encoding/decoding principles of H.264, with Jordan algorithm and characteristics of human visual system, an improved watermarking scheme for H.264 video was proposed. As to this algorithm, the watermark image, which was processed into binary, was transformed using discrete wavelet transformation (DWT).After the transformation, the low-frequency coefficients of watermark image were embedded into the high-frequency coefficients of Frame I of the video frequency, which was transformed using DCT transformation, while the Intermediate frequency coefficients of watermark image were embedded into the MV of Frame P of the video frequency. With MATLAB, the simulation tests of anti-frame deletion and other attracts were carried out. Experiments show that this scheme can not only ensure the capacity and the watermarking invisibility, but also enhance the robust of watermarking.
Wang M.,Gui Zhou University |
Li Y.,University of Science and Technology of China
Expert Systems with Applications | Year: 2014
Traditional DEA method is improper for supplier evaluation and selection, as it adopts varying weights in evaluation, and fails to consider competition among the suppliers. In order to solve these two problems, Nash bargaining game DEA model is applied to supplier evaluation in present paper. However, there is a non-uniqueness problem with Nash bargaining game efficiency of supplier in existing Nash bargaining game DEA model. The existing Nash bargaining game DEA model is improved in present paper on this issue, then the improved model is applied to the third party logistics service provider evaluation. The result of supplier evaluation based on the improved model is more persuasive compared with the existing research achievement, owing to adopting common weights in evaluation, and the game between suppliers being taken account. © 2014 Elsevier Ltd. All rights reserved.