Advanced Materials Research Vols. 712-715

Abstract: The paper puts forward an algorithm base on the strategy of sensor nodes dynamic clustering which also combined the method of particle filter to track the target. The simulation shows that the algorithm efficiently reduces the amount of communication between the redundant nodes and sensor nodes, decreases the energy consumption of the entire network, extends the network life span and improves the tracking accuracy.

Abstract: With the development of internet of things (IoT), various of sensors play important roles in applications, especially in smart grid. The electrical substations usually deploy many sesors to sense the environment or control power facilities etc., such as temperature and humidity sensor, SF₆ sensor etc, to organize as a wireless sensor network (WSN) to cooperate for intelligent operation. In this paper, we deploy some special sensors in the substation and design a hierarchical architecture of WSN for information collection. According to the observation and operation result, the wireless sensor network can effectively acquire the environmental object and monitor the substation assets, which can effectively improve the operation capability of substation.

Abstract: The performance of induction coil magnetic sensors , which usually have large dimensions and heavy weights, is mainly decided by apparent permeability of the core. But flux concentrator is a effective equipment to improve apparent permeability of the core, which will hardly increase dimensions and weights of magnetic sensors. Firstly, mathematical equations of apparent permeability are explained and influencing factors are analysed. Then influencing degrees of different parameters of the flux concentrator are simulated by Maxwell 2D/3D. The results are shown as follows. (a) The larger diameter and thickness of the flux concentrator, the better is the effect of magnetic concentration. (b) The less the gap between core and concentrator, the better is the effect of magnetic concentration. (c) The larger relative permeability of the flux concentrator, the effect of magnetic concentration is unconspicuous for the material whose relative permeability is larger than ten thousands.

Abstract: A class of single-resistance-controlled (SRC) quadrature sinusoidal oscillator using CFOAs for GMI magnetic sensors is presented in this paper. By means of state variable, the proposed circuits are designed and analyzed which has the advantages such as noninteractive control of the oscillation condition (CO) and the oscillation frequency (FO), good sensitivity performance and minimum components including grounded capacitors. Moreover, the workability of the proposed circuit has been verified by PSPICE simulations.

Abstract: For designing GMI sensors, realization of current/voltage-mode (dual-mode) quadrature sinusoidal oscillator with the employment of current follower transconductance amplifier (CFTA) as the active component is presented. The proposed circuit configuration comprising two CFTAs, one grounded resistor and two grounded capacitors can simultaneously provide two explicit quadrature output currents and two quadrature output voltages. Moreover, the proposed circuit topology enjoys the advantage of independent control of the condition of oscillation and frequency of oscillation and good active and passive sensitivity performances. The functionality of the proposed quadrature oscillators has been verified by PSPICE simulations.

Abstract: nertial sensors based on Micro-electro-mechanical systems (MEMS) are leading a great prospect because they are cheap, small and light. However, large errors limit their applications in many Inertial Navigation Systems (INS). To improve accuracy of INS based on MEMS sensors, a systematic error auto-compensation method, Rotation Modulation (RM) is introduced. RM improves navigation performance without involving any other information sources, saving the essential characteristic of self-contain. The RM effects on sensor biases and navigation errors are analyzed. Different RM schemes including elements like number of rotating axis, rotation direction, continuity and speed are discussed. An INS based on MEMS sensors with an appropriate RM scheme is developed. Static and land vehicle tests are conducted, verifying the effectiveness of RM on improving inertial navigation performance. Through introducing RM, attitude accuracy is improved by 5 times, and velocity/position accuracy by nearly 10 times.

Abstract: Concerning intelligence control of sizing machine in textile process, resistance strain gauge sensor is used to detect the winding tension of weavers beam, capacitance level transducer can be used to monitor the level of size glue in sizing box so as to maintain the constant sizing regain , photoelectric encoder is a key device for regulate the elongation for various zone with the help of frequency converter governed by PLC , photoelectric encoder is indispensable for regulation of elongation.4444

Abstract: The methodology of the direct calibration for the electromagnetic flowmeter in partially filled pipes is presented in this paper. Based on the principle of the electromagnetic flowmeter, two main respects, including the flow liquid level and the weight function in partially filled pipes are introduced briefly, and the calibration technologies of the sensor, which consist of the device arrangements, the accurate measurement of the liquid level and the calibration of the flow discharge, are emphasized on, with the methodology based on the piecewise interpolation employed. The experimental results demonstrate that the methodology of the direct calibration is simple and effective for the real flow calibration of the electromagnetic flowmeter in partially filled pipes, with the stable measurement and the accuracy requirement satisfied.

Abstract: In order to optimize the structural design of gas turbine flowmeter sensor, numerical simulation of internal flow for gas turbine flowmeter is conducted with computational fluid dynamics method. The computation have been carried with three dimensional modeling, high quality grid resolution, dynamic grid technique and companying with the practical application of specical boundary condition.The detailed information of velocity distribution and meter factor of gas turbine flowmeter are obtained. Compared simulation results to experimental data, the relative errors are within 2.7%.

Abstract: A new kind of electrode was designed for micro-structural gas sensor based on silicon substrate. The temperature distribution was simulated by means of finite element analysis tool ANSYS, in order to obtain higher temperature and uniform temperature distribution in the micro-gas sensor, the thickness of SiO₂, thickness of Si substrate, electrode width and electrode space is designed to be 50, 250, 10 and 350 µm, respectively. The magnetic field distribution was also analyzed by ANSYS, and the results show that the new electrodes can eliminate the magnetic field from the heater on the measurement signal interference, which is benefit for the improvement of sensor performance.