Applied Mechanics and Materials Vols. 701-702

Abstract: In order to establish monitoring systems for micro vibration due to electric spark occurs in the faulty cable, a novel acceleration sensing structure utilizing the piezoresistive principle is presented. The mechanical model and its mathematical solution are established, which have been developed in order to calculate the sensitivity and frequency behaviour of an acceleration sensor. The sensor is built up as a sense beam and a supplement beam is supposed to have high sensitivity, low resonant frequency and minimized lateral effect. For the designed sensor structure, the formula of stress, natural frequency and damping was derived in theory, and the optimized structure is confirmed through adjust the beams size.

Abstract: The control system of the spring tension and compression testing machine is designed based on STM32 processor and touch screen. The signal of the pull-pressure sensor after conditioning is conversed by the 24bit A/D converter. The signal is operated real-timely with the encoder data, the setting value of the touch screen and the condition of the keys. The results are stored in the SD card. While the results are displayed on the touch screen. The anti-interference capability of the system is improved by the hardware and software anti-interference design. The reason of the measurement results smaller than the theoretical value is analyzed according to the tests results used of the calibration texting machines. Two aspects of the measures have been proposed to improve the measurement accuracy, including improving hardware stiffness and introducing distortion compensation amount.

Abstract: It is important in chestnut industry to evaluate the sugar content of nuts since sugar content is one of parameters for classifying the fruit to different productions. Previous work had proved the near infrared (NIR) spectroscopy could be used to measuring the sugar content in intact and peeled chestnut nondestructively; however, the performance of the predictive model would need more improvement. In this work, the orthogonal signal correction (OSC) algorithm was employed to optimize the predictive models. The results shown that, for the peeled chestnut sample, OSC could increase the correlation coefficient (R2) of validation set from 0.8649 to 0.8961while decrease the root mean and square error of prediction from 0.739 to 0.626. For the intact chestnut sample, this algorithm did not improve the model performance. The results indicated that the OSC had potential to optimized the prediction accuracy of sugar content in chestnut based on near infrared spectroscopy.

Abstract: The necessity and advantages of the multi-sensor’s application in information fusion is analyzed on the basis of that multi-sensor information fusion technology has been widely applied in the monitoring and control system of seafloor observatory network. and the structural model of fusion system based on the distributed filtering scheme is presented. Decentralized kalman filtering is proposed to solve the fusion structure model of the system, and the information fusion algorithm based on kalman filtering is discussed in depth. And the research findings of Kalman filtering in information fusion are tested with Mat lab. Simulation shows that system design can integrate the lowest layer of sensor signals quickly and accurately, giving helps for decision making.

Abstract: In the mid-1980s, in order to enhance the image of modern banks, the banks in China began to introduce ATM (automated teller machine), which has become an important tool for cash flow of the financial system. ATM has brought us convenience, meanwhile,security issue has become the most concerned issue of the financial system. How to realize ATM’s digitization, networking, and intelligence Since the late 1990s, China has begun to invest a lot of manpower and materials to conduct research on ATM, but there are still many problems. From the existing disadvantages of ATM’s system, this article introduces a full range of vision sensor to ATM intelligent monitoring field, which overcomes the defects of existing monitoring systems, such as small scope,low intelligence level, image information fusion problems, etc..

Abstract: A wireless temperature and humidity monitoring system for workshop with constant temperature based on AT89C52 Single chip microcomputer and nRF905 wireless microchip is studied. The system is consists of base station and slave station. Base station is mainly consists of temperature acquisition module, humidity acquisition module, wireless communicating module and communicating testing module. Good communication protocols play an important role in ensuring the correct monitoring data. So the network topology, communication data form, ad hoc networks protocol, mac protocol and data link layer protocols are discussed for commutation protocol to host computer software. The cost of the system is low and it has a large function area and a good performance. It is able to provide messages of workshop with constant temperature for improving machining accuracy and prolonging the life of equipment in machine shop.

Abstract: Specifically focusing on the electric safety of students, we proposed a College Apartment Fire Monitoring System using the combination of wireless communication network and environmental sensors. The system adopts GSM as the data carrier and STM32 as data processing chip, combines sensor detection module and power supply control module together, synthesizes the data information from each sensor module, estimates the possibility of catching fire and shuts off the electrical power in the breakdown region timely. At the same time, the system informs the control center and dormitory managing clerks to check in order to minimize the risk of catching fire. This system can monitor the factors of apartment fire, establishing a set of real-time college apartment fire monitoring system.

Abstract: A parameter design of a pinhole array is one of the most important keys to design an integral imaging (II) display using pinhole array. The relationship between the thickness of the pinhole array and the viewing angle of the II display is studied, and the maximal value of the thickness is also obtained. When the thickness of the pinhole array is greater than the maximal value, the viewing angle of the II display is decreased with increasing the thickness of the pinhole array. A prototype of the II display using pinhole array is developed, and the experimental results agree well with the theory.

Abstract: For application in the magnetic material at high temperature, the equipment for the measurement of magnetic properties of hard magnetic material at elevated temperature has been developed. The temperature coefficient of remanence and coercive, demagnetization curves at different temperatures was measured by this equipment. The heating plate which using the mesh screen printer substrate method was designed to realize the accurate measurement in the quasi closed magnetic circuit .The temperature measuring range is from room temp. 500 °C.

Abstract: Wavelet decomposition on acoustic spectrums is a novel method in the field of gas composition sensing. However, the existing method doesn’t explain the relationship between the characteristics of acoustic gas spectrums and the results of wavelet decomposition, and it has high computational complexity. In this paper, we firstly find it can basically keep the recognition rate if the detail coefficients from wavelet decomposition are used to construct samples instead of characteristic coefficients extracted from the detail ones. Nevertheless, the detail coefficients can represent the properties of acoustic gas spectrums, which can’t be represented by characteristic coefficients. Then, we find points of detail coefficients with relatively high recognition rate are mainly distributed in the first three layers. Therefore, it can reduce the computational complexity when three-level decomposition is directly utilized in the method of gas composition sensing.