Advanced Materials Research Vols. 301-303

Abstract: Through the analysis of vehicle dynamic and characteristic and vehicle-road environment, the ESP stability boundary can be easily determined. But from the point of the system vehicle-driver-environment, ignoring the analysis of driver operation behavior in extreme situation, it is difficult to determining the system optimization direction reasonably and improving the ESP system control quality based on the analysis of ESP system response performance and vehicle comfort performance when brkae intervening. Based on the driver’s complaint analysis in ESP performance test, combing with the aim of active safety system, this paper comes up with a set of new guidelines to design and development ESP system from the point of vehicle-driver-environment system.

Abstract: Photoelectric detection technology is a kind of new technology of non-contact measure, and it is one of the most important means and methods of modern detection technology. The design of the high precision sunlight intensity measurement device is based on photoelectric detection technology. The sunlight intensity energy is received by the photodiode, and then it is transferred into electrical energy, the current. After the filtration and amplification, the current is converted into digital signal by the ICL7106 A/D converter. Ultimately, the accurate value is displayed on the LED digital tubes. The value shows the sunlight intensity at the moment of the measurement. The experimental result shows that the sunlight intensity is different at the different times.

Abstract: A short time high power pulse is stimulated by the LC circuit. Through a send winding, the electromagnetic guided wave signals transmit in the metal pipes. A receive winding is mounted around the pipe to collect the receive signals. The receive signals are different if there are several defects in the metal pipe or not. To analyze the instantaneous pulse group, a method of multi-scale entropy is adopted. The receive signals are transformed to a data sequence. In terms of the entropy values of the sequence at different scales, the complexity of the data sequence is gained. The defect information is contained in the entropy value varied curve.

Abstract: This study discussed the feasibility of taste quality evaluation for green tea infusion using electronic tongue. Chemistry evaluation was regarded as the reference measurement, and used to measure total taste scores of green tea infusion. LS-SVM was used to build the correlativity between the sensor signals of green tea infusion and total taste scores by the reference measurement, and compared the influence of different principal components on the performance of LS-SVM model. Experimental results showed that the optimal model was obtained when 4 PCs were included with Rc=0.951 and RMSECV=3.242 in calibration set, Rp=0.904 and RMSEP=4.134 in the prediction set. This study showed that the electronic tongue had a great potential in the evaluation of taste quality for green tea and LS-SVM was an efficient method to build the evaluation model based on electronic tongue.

Abstract: On the basis of a large number of continuous monitoring experiments for the five-line salinity of seawater, and the uncertainty of natural seawater oxidation reduction potential (ORP) is 2.2mV, the effect of seawater salinity on the equilibrium time of ORP is studied qualitatively and quantitatively. The results indicated that the greater the salinity, the longer the time of reaching to ORP equilibrium value, the longer the equilibrium time of the seawater ORP value. It is showed that the ORP equilibrium value was obtained at 30minutes, 90minutes, 120minutes, 240minutes and 300minutes from seawater with salinity as 5,20,30,35 and 40, respectively, and the equilibrium time was more than 12 hours. Accuracy and stability of the equilibrium time of seawater ORP value under different salinity can provide technical support for metrological verification of ORP sensor.

Abstract: DC motor driven systems include both the electrical and mechanical parts, leading to parameters changes because of interactions. An example is the torsional modes of drive train, which frequencies might be different with and without taking into account the electrical power system. Therefore, in this paper, we propose an electromechanically integrated circuit model to overcome the difficulty. Sinse the whole-circuit model can be used to modify the mode frequencies obtained from tests on a mechanical system alone, it will be a good testing support for a DC motor driven system.

Abstract: In this paper, the characters of the 4-9-9-14 piezoelectric actuator would be analyzed, and the fuzzy controller is designed to control the rotating velocity of piezoelectric driving platform. There are many kind of analysis which are about the 4-9-9-14 piezoelectric actuator would be done in this paper, including of finding the resonant frequency of the actuator, setting the equivalent circuit, analyzing the quality factor of the actuator, measuring the temperature of the actuator surface, and doing the simulation of the circuit by IsSpice which is used to observe the characters of the 4-9-9-14 piezoelectric actuator. There is higher nonlinear character of piezoelectric material which extends different tensile length when it is given the same input-voltage. Because of this reason, the rotating velocity of the piezoelectric driving platform is always unstable. The fuzzy theory which is used for the controller designed would be used to let the piezoelectric driving platform be stable. The interface, GPIB, is used to adjust the input voltage for the piezoelectric actuator. When the input voltage for the piezoelectric actuator could be controlled, the rotating velocity of the piezoelectric driving platform could be controlled too.

Abstract: Traditionally, the first step to analyze the steady-state error of nonunity feedback control system is to convert the system into an equivalent unity feedback control system, and calculate the steady-state error by using the concept of type number for unity feedback control system. In 2011, Mou is based on the concept of old type number and the definition of new steady-state error functione(t)=(1/K_H)r(t)-y(t) by Kuo to offer the method for calculating the steady-state error of nonunity feedback control system. In this paper, three typical examples will be analyzed by the calculation of step response and by the simulation of Matlab. Therefore, we can prove that the definition of new steady-state error function e(t)=(1/K_H)r(t)-y(t) by Kuo and the concept of old type number are useful to solve the steady-state error of nonunity feedback control system.

Abstract: Permanent magnet synchronous machines (PMSM) are appealing candidates for many high-performance applications such as robotics, machine tools and other electrical propulsion system because of their attractive characteristics. PMSM have advantages of high power density, high torque-to-inertia ratio, and high electrical efficiency. However, the main disadvantage of PMSM is the torque ripples. Therefore, the study of how to compensate the torque ripples so as to improve the tracking performance of PMSM is very meaningful and necessary. In this paper, we focus on the control of a non-sinusoidal permanent magnet synchronous machine. First, we compare the various methods which to reduce the torque ripple. Then, we built a basic PMSM model. After that the Iterative Learning Control (ILC) algorithm is applied to compensate the torque ripple, and improve the tracking performance of the PMSM. The effectiveness of using ILC method to reduce torque ripple is demonstrated by simulink results.

Abstract: The conventional methods for pika observation and investigation are costly both in material resources and manpower, moreover these approaches are difficult to use in long-term and continuous investigation. In this context, a plateau pikas monitoring scheme based on image processing technology was described, and the steps of pika identification is presented. Furthermore, the most challenging issue of pika identification, feature extraction was analyzed in detail. Based on the analysis, the image graying method was utilized to avoid redundance and compress data capacity, and image binarization technology was utilized to eliminate the background noise. Moreover, in order to effectively extract the features, four edge detectors: Sobel, Prewitt, Roberts and Canny were chosen for evaluation, and among these algorithms Roberts detector were found has better performance in the application. At last, median filtering method was utilized in image smoothing for spiky noise elimination and sharp edges preservation. The experiment results showed that the pika detection method based on image processing has the advantages to achieve dynamic and continuous monitor of pika in close quarters, and significantly improved the technique in meadow biogeocenose protection.