Advanced Materials Research Vol. 739

Abstract: Laplace wavelet transform is self-adaptive to non-stationary and non-linear signal, which can detect the singularity characteristic of a signal precisely under strong background noise condition. A new method of bearing fault diagnosis based on multi-scale Laplace wavelet transform spectrum is proposed. The multi scale Laplace wavelet transform spectrum technique combines the advantages of Laplace wavelet transform, envelope spectrum and three dimensions color map into one integrated technique. The bearing fault vibration signal is firstly decomposed using Laplace wavelet transform. In the end, the multi scale Laplace wavelet transform spectrum is obtained and the characteristics of the bearing fault can be recognized according to the multi-scale Laplace wavelet transform spectrum. The proposed method has been verified by vibration signals obtained from rolling bearing with inner race fault.

Abstract: The newly developed Teager-Huang transform (THT) enables one to look at the evolution in time of a signals frequency components. In this paper, a novel application of Teager-Huang transform method to fault diagnosis of gear crack is presented. The methodology developed in this paper decomposes the original times series data in intrinsic oscillation modes, using the empirical mode decomposition (EMD). Then the Teager Kaiser Energy Operator (TKEO) technique is applied to each intrinsic mode function (IMF). Therefore, the time-frequency distribution of the vibration is obtained. The basic method is introduced in detail. The Teager-Huang transform is applied in the research of the faults diagnosis of the gear crack. The experimental results show that Teager-Huang transform can effectively diagnosis the fault of the gear crack.

Abstract: This paper briefly explains the advantages of LED and the classification of LED backlight and explores the pattern of LED backlight based on dynamic regional control technology to overcome and improve the inherent problems of LCD TV monitor on purpose of reducing power consumption and saving energy.

Abstract: In view of dew point corrosion for the emergence of low-temperature part of atmospheric and vacuum distillation unit, from the analysis of the main factors for the impact of dew-point temperature,we make the calculation of the dew-point temperature and composition of the liquid .And it is calculated through the examples of calculation steps. We can get a different component content will lead to the different dew point temperature, when the dew point temperature changes, the liquid component of the dew-point percentage and the position with the corresponding change.

Abstract: In order to evaluate the fatigue endurance for an ultra lightweight inline skate frame, FEM analyses was performed. The tensile properties and an S-N curve were determined through tensile and fatigue tests on a modified Al-7075+Sc alloy. The yield and ultimate tensile strengths were 553.3 MPa and 705.5 MPa, respectively. The fatigue endurance limit of this alloy was 201.2 MPa. To evaluate the fatigue endurance of the inline skate frame, the S-N data were compared with the stress analysis results through FEM analyses of the frame. The maximum von Mises stress of the frame was determined to be 106 MPa through FEM analysis of the frame, assuming that the skater weight is 75 kg. Conclusively, on the basis of the fatigue limit, the inline skate frame has a safety factor of approximately 2.0.

Abstract: A railroad bogie's components experience repeated loading during service. Especially, the oil-damper rubber bush becomes fatigue fractured on the plane between the rubber and the steel stem during service, and this results in inferior performance of the bogie. In this study, in order to offer a proper maintenance method for the bush, a novel service lifetime estimation for an oil-damper rubber bush operating under different repeated loads was proposed by normalizing the degrading rate of its spring constant. When 13,720 N, 11,760 N, and 9,800 N of repeated loads were applied to the rubber bush, final damage fraction was shown to be 63.7%, 50% and 40%, respectively. The normalizing lifetime (N/N_f) can be predicted as a function of damage fraction (D/D_f), regardless of the load amplitude, as follows: N/N_f = 0.043 + 0.376(D/D_f) + 0.489(D/D_f)².

Abstract: On the basis of study of traditional selection method about locking point, this paper made a large number of trial and comparative analysis for the selection of locking point, got a more effective method and gave the application example.

Abstract: In this paper, we present one method of acquiring the evaluation data of health habits using FitBit sensor. After registering in Fitbit.com, we create a customer client based on OAuth protocol and obtain the authorization of operational resources. Then we access to health habits assessment data, and complete data visualization. Finally, we provide the experiments results. The experiments results prove our method is feasible and valid. Our method has been used in our practical application.

Abstract: Discrete phase model was used for three-dimensional numerical simulation of two-phase flow in the ship FGD scrubber. The κ-ε model and SIMPLE algorithm were adopted in the calculation. The results showed that adding porous baffles improved the distribution of flow field in the scrubber. The gas velocity in the scrubber became uniformity and the flue gas resistance decreased when the sprays worked. Under the action of the spray, the differential pressure of spray area changed greatly. The simulation plays a certain role in guiding the structural optimization design of scrubber.

Abstract: The circuit of series switching power supply based on voltage and current dual-loop control is proposed, which can work in the voltage range from 12V to 90V. It is less influence to working state when capacitive load is accessed. The circuit have the function of quickly response, short circuit protection and overcurrent protection. The power supply have advantages of low-cost and working stability, which can be used to different various industry alarms and blasting signal lights in the wide voltage range.