Applied Mechanics and Materials Vols. 321-324

Abstract: Analysis of vibration or acoustic signals from rotating machines is often preferred in terms of order spectra rather than frequency spectra. An order spectrum gives the amplitude and/or the phase of the signal as a function of harmonic order of the rotation frequency. Order tracking requires sampling of the vibration signal at constant angular increments and hence at a rate proportional to the shaft speed. Most commercial software for signal processing has the built-in capability of computed order tracking, such as the 7702 order tracking software of B&K Pulse. The order tracking result of interior noise of cab is presented in this paper. From order tracking analysis on the noise of interior cab, we found that the noise mainly comes from the second order excitation of engine, and that the overall noise with respect to engine speed

Abstract: The choice of the number and location of sensors in the structure is the foundation of cranes structural health monitoring, which has major influence on the monitoring results. This paper taking a gantry crane as a SHM research object, uses optimal sensor placement based on Finite Element Method, the stress concentration points could be drawn by the FEM calculation results. This method carry out dynamic load stress analysis for the structure with virtual prototype, which make up for the lack of static analysis; compared with the type test methods, not only reduce the test cost, but also more flexible, and break through the restrictions of all types of extreme conditions. This method makes the sensor data obtained more realistically reflects the crane structure condition; provides reliable data support for crane safety monitoring and safety evaluation. The promotion of this method will provide important technical support for the development of the crane SHM.

Abstract: The author discusses the importance of Computer-aided translation (CAT hereinafter) translation technology as a result of the booming international communication and then probes into the research and development of CAT technology and its theoretical approaches, and finally looks into its future trend.

Abstract: To study the relationship between tongue temperature and the lingual circulatory system, the blood stasis and blood deficiency syndrome of traditional Chinese medicine (TCM) syndromes were researched by making animal model and vascular cast experiment. The influence of blood stasis and blood deficiency syndrome on tongue temperature and the lingual circulatory system were studied and analyzed. The experimental results indicated that the lingual circulatory system of blood stasis syndrome and that of blood deficiency syndrome were distinctly different in blood flow rate, vascular diameters and the density of small vessel. These differences in circulatory system could induce a change on lingual temperature. This result proves that the tongue temperature has relations with the change of lingual circulatory system.

Abstract: t is an important method for using electrocardiogram (ECG) to detect and diagnose heart function in clinical practice of medicine. Ventricular tachycardia (VT) and ventricular fibrillation (VF) are serious threats for peoples lives, they often bring about cardiac sudden death. In this paper, the complexity analysis method based on Jensen-Shannon Divergence was used to calculate the complexity of the normal sinus rhythm signals, VT, VF. The study found that the VF was highest, followed by that of VT, and that of normal sinus rhythm signals was minimum. The result can be used to assisted clinical diagnosis.

Abstract: Assessment the distinction of different brain working conditions is very important for brain function study. For the first time, detrended cross-correlation analysis (DCCA) was applied to analyze different brain working conditions. It were compared the difference of DCCA values for EEG signals under count number state and close eyes state. It was found that the DCCA values of count number state EEG signals decreased compared with close eyes state EEG signals which can be helpful for studying different brain state.

Abstract: In this paper, symbolic relative entropy was used to analyze the average energy dissipation of epilepsy electroencephalagram (EEG) signals and normal electroencephalagram signals. Hypothesis testing showed that the average energy dissipation of epilepsy electroencephalagram signals was distinctly higher than that of normal electroencephalagram signals. It discoved that symbolic relative entropy can be used to analyze the irreversibility of time series and to assess the health state of human brain. It can be used to assisted clinical diagnosis.

Abstract: A high-precision marine ambient noise sound pressure monitoring system is developed based on the Michelson interference, a method of improving the measurement accuracy is presented by signal modulation and compensation. Experiments show that the monitoring system has a wide dynamic range and high accuracy especially in low-frequency.

Abstract: According to the requirement of JJG443-2006 ,the solution of hardware design of late-model fuel dispensers automatic verification system is introduced in this paper, which makes use of four wire PT resistance and AD7712 as the acquisition circuit for getting temperature of oil tank and oil gun. In order to achieve the automatic verification of fuel dispensers, it also designs the measuring circuit for the flow rate of oil gun based on AD620 chip and the automatic camera module driven by stepper motor.

Abstract: Electronic components are the basis of electronic equipment, and their reliability and lifetime have a direct impact on the work efficiency of the whole electric system. In fact, the test data on life characteristic parameters (LCP) of electronic components present random fluctuations because of the existence of some disturbing factors in the process of life test. This will bring great obstacles to the study on the rules of LCP, the reliability and life forecasting of electronic components. In order to solve these problems, this paper proposes a method of the determination of weight coefficients and an improved weighted average algorithm to reveal the rules of LCP. In the improved weighted average algorithm, the latest data is constantly introduced while the oldest data is removed. By an example of contact bounce time on electromagnetic relay, the application verification has been carried out on the above-stated method in the paper. The results show that the method is effective and feasible.