Applied Mechanics and Materials Vols. 241-244

Abstract: In order to improve the positioning accuracy and reduce the localization cost, a kind of PSO-based RFID indoor localization algorithm is proposed in this paper. The main idea of this algorithm contains the following two aspects. First, due to the influence of none line of sight and multipath transmission in indoor environment, we adopt Gaussian Smoothing Filter to process Received Signal Strength Indicator (RSSI) values, which can reduce the impact of environmental factors on the position estimation effectively. Second, Particle of Swarm Optimization (PSO) algorithm is introduced to obtain a better positioning result. By experimenting in different indoor environment, the results demonstrate that the proposed approach can not only improve the precision of indoor localization, but has a lower cost and better robustness when compared to VIRE approach.

Abstract: The progress of electronic sensor technology has greatly enhanced the performance of vibration tests, and improved the accuracy and velocity of the measurement. This paper studies and designs a new non-contact optical vibration sensor based on the intensity sensor,and implementation the Optical fibre vibration sensor based on FPGA. The totally available measurement range arrived over 300um. This fiber optic vibration sensor has the advantage of good reliability, low cost, high accuracy measurements.

Abstract: The technique of ion mobility spectrometry (IMS) offers a practical and fast detecting method in ambient conditions to estimate whether there may presence contrabands or even chemical warfare agents (CWAs). In this work we have investigated a self-made radioactive 63Ni (β emission) ionization source for ion mobility spectrometry employed with an atmospheric pressure to detect real CWAs, such as GB, GD, HD, VX from aerosol samples. Furthermore, we have experimentally studied the influence of drift tube temperature not only in ion cluster formation in the positive mode, but also the detection limitation of CWAs.

Abstract: In the paper, a Double-notches Touch Mode Capacitive Pressure Sensor (DTMCPS) is presented. The sensor employs a special SiC-AlN-SiC sandwich structure to achieve high-accuracy pressure measurement in high-temperature environment. The simulation analysis to the relation of capacitance and external pressure of the sensor shows that the sensor has higher sensitivity and longer linear range than traditional one. At the same time, the technical process of the sensor has been designed in the paper. The research shows that DTMCPS packaged in a high-temperature ceramic package can withstand higher temperature. Consequently, the sensor can be applied in high-temperature and harsh environment.

Abstract: Amorphous alloy material has good soft magnetic properties, so it can be used for stress measurement. At first, the working principle of the stress measurement was analyzed. Secondly its output characteristic mathematical model was established by adopting multivariate linear regression analysis method, and the simulation of the mathematical model was made based on Matlab. Finally a practice measurement with Fe-base TM—M Amorphous alloy was completed. The results of the test have showed that the stress measurement method has some characteristics of being sensitiveness to measure and simple to make a testing system, and a promising method of measuring stress.

Abstract: Against the shortcomings such as high price and low precision , big error leading with land wheel exist shift phenomenon in traditional tachometry, raised that the idea of using multisensor data fusion handles operating machinery speed in the field, introduced a fusion progress system structure and applied the kalman filter data fusion algorithm.This system which is based on ATS665 and GPS and mcu MSP430F1121 can work in operating machinery speed measurement and in car navigation and positioning system .The above_mentioned determines the high reliability,high cost perfomance and using easily.

Abstract: In order to measure ground surface deformation, a sensor based on cable impedance change is studied in this paper. This sensing cable has elastic double helical structure with much larger measurement range than optical fiber distributed deformation technology. Using the precision impedance analyzer, we obtain the relationship between elongation and impedance of the sensing cable and choose one of the frequent as the measurement frequency. A ground surface deformation measuring circuit is designed for the sensing cable. Deformation experiment shows that the relationship between sensing cable impedance and stretching deformation is approximately linearity, when the deformation is small.

Abstract: Wireless sensor-actuator networks have gained widely applications due to its low energy consumption and increasing energy efficiency and bring flexibility to building control. Firstly, a smart building control prototype system is proposed in this paper. The general purpose is energy saving and emission reduction through the collaboration among a mass of low-cost sensor nodes and actuator nodes. Then, we detail the hardware and software in our building control prototype system. Finally, a set of experiments are presented to evaluate the performance of the proposed scheme key technologies.

Abstract: Array induction logging tools (AILT) detects the stratum conductivity based on the principle of electromagnetic induction, as a result, the signal of the amplitude using the AILT is in microvolt level. The small-signal is always drowned by noise at high-temperature and high-pressure condition. In order to collect the weak signal accurately, we propose a design method of signal modulator circuits based on the principle of differential amplifier and active band-pass filter with second band limitless gain and multi-path negative feedback. First, make the induction signal obtained from the coil two stages amplification. Then Execute two-order band-pass filter to the enlarged signal. At last, process the filtered signal by the backward circuits. Simulating the circuits by Pspice16.3, The result of simulation indicated that the gain relative error of preamplifier is less than 1% and the center frequency relative error of band filter is less than 4%. These data suggest that the relative error of the design circuits is less than routine instrument by 5%. So the Simulation verifies the feasibility of the signal modulator circuit.

Abstract: Aiming at the energy heterogeneous wireless sensor network, this paper proposes This paper proposes the remaining energy prediction model based on energy matrix and a novel clustering algorithm .The Kalman filtering algorithm was introduced into the model, in which a node , according to energy prediction mechanism , independently makes it s decision to compete for becoming a master cluster head in order to improve energy efficiency. Simulation results show that the algorithm can balance the network energy consumption, improve the utilization efficiency of node energy and prolong the network lifetime.