Applied Mechanics and Materials Vols. 411-414

Abstract: Because that the wear of the machine cutting tool of the aeroplane composite material processing is difficult to be monitored, in this paper a monitoring method based on the cellular neural networks by the computer vision monitoring is proposed. The method uses the median filtering technology and the cellular neural networks for the image denoising and the edge detection. Then the degree of the tool wear is judged by calculating the wear characteristic value of the cutting tool. The experimental results show that the system is rational and effective.

Abstract: Surveying the damaged site on anticorrosion coating of Underground metal pipeline is currently a realistic problem in pipe network construction projects, They are detected through artificial field source method (DC method), including Person method,potential test method,Close interval pipe-to-soil potential survey and Direct Current Voltage Gradient method, but the principle of detecting about electrical method rare mentioned, the article discusses the forward modeling and inversion method of Surveying the specific damaged site on anticorrosion coating of Underground metal pipeline by DC method in great detail, Through calculation and analysis, The authors believe that the DC method is effective in detecting the damaged site on anticorrosion coating of Underground metal pipeline.

Abstract: A set of temperature measuring system hardware circuits is presented and investigated regarding to static errors. The measurement accuracy of the system can be up to 1%in the industrial applications. In addition, this paper proposes a recommending method to select hardware equipment and this approach plays an important role in temperature measurement in industrial applications.

Abstract: The applications of quartz for electric devices had been progressed for a long time. In the early period, the primary application of quartz is focused on the crystal resonator and filter^1-4). The other important application of quartz is on the QCM(quartz crystal microbalance). The basic principle of QCM is based on the mass loading effect, which makes the resonator frequency shift and the mass loading is directly proportion to the shift of frequency. V.M.Mecea has shown the theory of mass loading and its applications⁵⁾. For using quartz as microbalance or sensor, an electronic circuit for change the shift of frequency to electronic signal is necessarily. Unfortunate, another important influence of mass loading is the inharmonic mode appearance with large mass load and inconveniently for designs the electric circuit. So a pure fundamental mode resonator is expected for used the quartz as sensor devices.

Abstract: The performance of the RFID tag which was implanted into the tire was studied. The shape of implanted RFID antenna, package form and the process of RFID implantation were given. In the same time, experiments were carried out to test the performance of RFID tag which implanted into the tire. The results show that: the read distance is shorten after implanted in the tire, the sidewall of the tire is the idea position for RFID tag implantation, and it can achieve good performance by changing the structure of the RFID antenna and improving implantation process.

Abstract: The working principle and architecture of UPQC is described. On the basis of analyzing the difference characteristic of series part and shunt part, used difference check and control strategies. Some simulation about UPQC are made by using MATLAB software, the results indicate that UPQC has better power quality ability and good application prospects.

Abstract: This paper presents a low-voltage differential operational transconductance amplifier (OTA) with enhanced DC gain and slew-rate. Based on the current mirror OTA topology, the optimization techniques are discussed in this work. The proposed structure achieves enhanced DC gain, unit gain frequency (UGF) and slew-rate (SR) with adding four devices. The design of the OTA is described with theory analysis. The OTA operates at the power supply of 1.8V. Simulation results for 0.18μm standard CMOS technology show that the DC gain increases from 60.6dB to 65dB, the UGF is optimized from 2.5MHz to 4.3MHz, the SR is enhanced from 0.88 V/μs to 4.8 V/μs with close power consumption dramatically.

Abstract: The classical model in digital DC-DC converter is digital pulse width mode (DPWM), but the digital pulse frequency mode (DPFM) is very important in DC-DC converter with light load. This paper presents the different application environments and the effect between the two modes. There are two common different DPFM structures analyzed in this paper. And a novel DPFM circuit is proposed, which needs only external clock, not affected by the duty cycle of the clock. The circuit and layout are designed with 0.13um CMOS technology. The simulation results of the circuit meet the requirements of design.

Abstract: The accurate electrical properties of semiconductor GaN based blue Light-Emitting Diodes (LED) with Multiple-Quantum Well (MQW) structure and GaAsP based red LED, were measured by single Capacitance-Voltage (C-V) method and single Current-Voltage (I-V) method at large forward bias. After comparing the experimental results, we found that the apparent capacitance C_p of GaN based blue LED and GaAsP based red LED measured by C-V method display obviously negative value at large forward bias and low frequency, which is in conflict with the well known Shockley's p-n junction theory and model. Besides, the precise Characterization of apparent capacitance C_p and apparent conductance G_p is obtained.

Abstract: This paper introduces fuzzy neural network technology into the adaptive filter and makes further research on its structure and algorithms. At first, fuzzy rules are determined and the network structure is built by means of dividing fuzzy subspaces. Secondly, membership functions are chosen layers are defined and the network is trained by adaptive learning algorithm. Thirdly, training error is the minimum with repeating debugging. Finally, linking weight, the central value and width of the network membership function is adjusted by using experience of experts. The optimal performance of Adaptive Wiener Filter is realized based on Fuzzy Neural Networks.