Advanced Materials Research Vols. 718-720

Abstract: The present study focuses on the robust fault detection issue within the synchronization process of nonlinear Lur'e dynamical networks. Sufficient conditions in terms of linear matrix inequalities (LMIs) are established to guarantee global robust synchronization of the network. Under such a synchronization scheme, the error dynamical system is globally asymptotically stable, the effect of external disturbances is suppressed, and at the same time, the network is sensitive to possible faults based on a mixedperformance.

Abstract: We propose a design of low power underwater acoustic receiving circuit by inverted echo sounder (IES) for observing the internal waves of the ocean in a long term. To receive the echo of the underwater targets, the underwater acoustic signal processor is required to be insensitive to strong noise and work in large dynamic range. In this work, with the variant application environments, to reduce the load of the subsequent processing modules, the circuit with digital gain control is employed to amplify the weak signals. Then, the out-of-band noise and higher harmonic are filtered out. The output is finally obtained by the 24-bit high-precision A/D sampling. Experiments demonstrate that the proposed design of the circuit performs with low power consumption, low noise, large dynamic range, flexible frequency selectivity, high precision and anti-inference.

Abstract: A novel insulation monitoring method which can monitor the insulation resistance between both the positive and the negative electrode of the electric vehicle's battery pack and the vehicle's body is proposed. The insulation monitoring method proposed in this paper is deduced theoretically, and the hardware and software design of an insulation monitoring device based on this method is given. The experimental results prove the correctness of the insulation monitoring method and the practicability of the insulation monitoring device.

Abstract: The temperament research is important to adjust accurately and stably the pitch of the piano. The purpose of the paper is to explore the scientific and effective temperament method. The piano temperament has inherited mostly the traditional temperament mode by the left or right hand for a long time. However, it is fuzzy that which kinds of the temperament methods have more advantages. Therefore, the stress of the strings was analyzed, and the traditional temperament methods were compared, so as to explore more scientific temperament method according with the stress rule of the string.

Abstract: On the road, fuel meter and electric power meter were employed to measure fuel consumption and electricity consumption of two parallel hybrid electric vehicles (PHEVs); Corrected methods recommended by SAE J2711 and GB/T 19754 respectively were used to modify fuel consumption of two vehicles through electricity consumption; According to the result, how total quality and Air-Condition (AC) load affect fuel economy were analyzed. Test results showed that, When K was less than 1%, relative error from calculation results of fuel consumption per 100 km obtained by above two methods was within 0.7%; Compared with AC off condition, fuel consumption per 100 km of PHEVs under AC on condition increased by more than 42%, which caused bad fuel economy, the effect of fuel-saving was decreased by 10% or more accordingly.

Abstract: This paper presents a novel construction method of brain functional network by using spatial mutual information to estimate quantitatively correlation between different channels of electroencephalogram (EEG) signals. Firstly, 32-channel EEG signals were collected and the alpha rhythm of each signal was extracted by a wavelet packet filter, the spatial mutual information of different EEG channels was calculated respectively, the appropriate threshold was selected to construct the functional network. Then the research framework was applied to characterize the brain network difference of the schizophrenic patients and the control group. The result indicates that the network construction method proposed in this paper could portray different brain function states and it also can become a new effective method in analyzing and understanding the mechanism of patients with schizophrenia and other mental illnesses.

Abstract: Dual-directional couplers are used to monitor net power fed into transmitting antennas in standard-field systems at NIM, China. It is essential to calibrate the coupler and evaluate the measurement uncertainty in the net power in such applications. The method we use at NIM to calibrate couplers are presented in this paper, and a complete model that takes into account the measurement uncertainties of couplers and horns to evaluate uncertainties in net power delivery is proposed. A case study is also provided of power delivery by a coupler with the nominal directivity of 40 dB using the Monte Carlo analysis based on the complete model and actual measured data.

Abstract: To study the effects of different oral environment factors on the friction and wear properties between dental prosthetic materials and natural teeth, several comparing experiments were implemented by using a reciprocating friction and wear test machine containing an artificial saliva solution. Three kinds of factors including load, frequency and cycles were investigated on titanium alloy TC4 and zirconia ceramic. The experimental results showed that zirconia ceramic has a better wear resistance and a lower friction. The wear loss of titanium alloy TC4 was 10 times of that of zirconia ceramic under same conditions. A significant positive correlation between three factors and wear loss was also discovered.

Abstract: The degree is an important parameter for B-spline. In this paper, as one example of optimal design in mechanism, the optimal design of the cam curve to control the residual vibration of the follower output for an indexing cam mechanism is taken and the effect of the degree of the B-spline to describe the cam curve on the optimization performance is discussed by obtained results.

Abstract: The statistical analysis for frictional resistance of bolting and shotcrete roadway is carried out by using the software of SPSS and statistical principle and combining the coal mine ventilation theory with the actual situation in Nanyangpo coal mine. The results show that the frictional resistance coefficient does not follow normal distribution and the 95% confidence interval is 0.0063~0.0087 N.s²/m⁴ for frictional resistance coefficient of bolting and shotcrete roadway. The comparison analysis of hectometer friction ventilation resistence is carried out between the statistical results with the actual measurement data in Nanyangpo Coal Mine, and its correlation is highly significant. It verifies that the statistical results is right. It has important application value for increasing the ventilation management level and ensuring the safety production of coal mining enterprises.