National Key Laboratory for Electronic Measurement Technology

Taiyuan, China

National Key Laboratory for Electronic Measurement Technology

Taiyuan, China

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An K.,National Key Laboratory for Electronic Measurement Technology | Li P.,North University of China | Chen D.,North University of China | Chou X.,National Key Laboratory for Electronic Measurement Technology | And 4 more authors.
Solid State Communications | Year: 2014

Antiferroelectric (Pb, La)(Zr, Ti)O3 multilayer thick films with thickness of 3817 nm were fabricated by sol-gel processing on Pt(111)/Ti/SiO2/Si(100) substrates. The characteristics of the phase transition current induced by temperature and transient pulse electric field were further investigated in detail. It showed that the phase transition current density was about 1.25×10-6 A/cm2 in the thermo-electric coupled field, which was 10 times smaller than that in a single temperature or electric field. In addition, the transient phase transition current density induced by pulse-voltage was up to 2.48×10-5 A/cm2, which could be used as the trigger signals in sensor and micro-switch in the complicated circumstance. At the same time, the results showed that the films had good reproducibility and stability by many repeated experiments. These results were very important for the antiferroelectric materials applied on micro electromechanical systems (MEMS) devices. © 2013 Elsevier Ltd. All rights reserved.


Zhen C.F.,North University of China | Liu W.,North University of China | Liu W.,National Key Laboratory for Electronic Measurement Technology | Hou Y.,National Key Laboratory for Electronic Measurement Technology
Sensors and Transducers | Year: 2013

Recent advances in technology have made low cost and low power wireless sensors a reality. Time synchronization may play a key role in wireless sensor networks. In this paper, The AORBS (accurate Ondemand Reference Broadcast Synchronization Protocol) mainly made two improvements on the basis of typical RBS algorithm. Firstly, the node clock is not synchronized with the natural frequency at all time, and the synchronization algorithm will take effect only after an event of interest has happened. Waste is reduced since the system avoids performing synchronization at times when it is not necessary. Furthermore the algorithm achieves the drift compensation by using Taylor expansion but not the linear regression method, greatly reducing the computation cost and improving the synchronization accuracy. As shown in our experimental results: the improved algorithm is more efficient and can be applied to a variety of scopes and types of wireless sensor networks. © International Frequency Sensor Association (IFSA). All rights reserved.


Zhang X.-F.,North University of China | Gao Y.-B.,National Key Laboratory for Electronic Measurement Technology
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

Target recognition is measured by treating target existing knowledge to judge, analyze, and thus the process of target identification. Using anti-vibration lateral shearing interferometer to get the interference fringe for the spectrum information of measurement target, and the system can get the target by spectrum identification algorithm. By the condition that interferometer's length isn't changed, the system was optimized by momentum BP Neural Network algorithm in the separating mixed spectrum process, therefore it could improve the probability of camouflage target recognition. The spectrum information was calculated by the fringes, to getting the mixed spectrum data. The absorption spectrum was in the hidden layer, and the system obtained every kinds of characteristic spectrum from mixed spectrum by the momentum BP Neural Network. Experiments showed that it collected mixed spectrum of background form different distances and different surface, and made them to the initial spectrum information. The test target was a board that it's surface was made to four kinds, and there was no paint (A), brushing camouflage paint of military green (B), brushing camouflage paint of irregular shape (C) and brushing camouflage paint of irregular box (D). The mixed spectrum was obtained from the anti-vibration lateral shearing interferometer, while the recognition probability for non-camouflage target were above 90.0% by the traditional algorithm and the momentum BP neural network algorithm, but the recognition probability for camouflage target was 85.6% by momentum BP neural network algorithm, better than 41.5% by the traditional algorithm, so it proved that the algorithm could improve the recognition probability for camouflage target effectively. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).


Sun G.-Q.,National Key Laboratory for Electronic Measurement Technology | Sun G.-Q.,North University of China | Jin Z.,North University of China | Tan Q.,National Key Laboratory for Electronic Measurement Technology
Journal of Biological Systems | Year: 2010

In semi-arid environments, vegetation is not homogeneous, but rather self-organized into spatial patterns. And spatial patterns of vegetation are a central feature of these semi-arid areas. Thus, in this paper, we give detailed analysis of a vegetation model in arid ecosystems. According to the dispersion relation formula, we discuss the changes of the wavelength, with respect to the rainfall and plant mortality rate. The obtained results show that, as rainfall being decreased, spotted, striped and "black-eye" patterns emerge successively. © 2010 World Scientific Publishing Company.


Li X.,National Key Laboratory for Electronic Measurement Technology | Zu J.,National Key Laboratory for Electronic Measurement Technology | Ma T.,National Key Laboratory for Electronic Measurement Technology | Xu P.,North University of China
IEEE Sensors Journal | Year: 2011

The research and development on a novel capacitive pressure sensor with an elastic pressure-sensitive element are presented in this paper. As a coaxial cylinder capacitor converter, it uses a circuit cylinder as its stationary anode and the piezo gauge's shell as its moveable cathode with the electrode distance of 0.5 mm. The device's principle and structure are given, and its mechanical characteristics are theoretically simulated by using the finite element software ANSYS. The read-out circuitry was developed. Various physical properties were experimentally tested. Results show that its capacitance is approximately linear to the subjected pressure. Its sensitivity is 0.0099 pF/Mpa, pressure measuring rang is 0-600 Mpa, By using the sensor's shell as its elastic sensitive element, its volume is reduced and its applications are increased, thus it can be used to measure the chamber pressures of various different caliber guns. In addition, its lower cost is helpful to promoting its applications. © 2006 IEEE.


Han Y.P.,National Key Laboratory for Electronic Measurement Technology | Li R.H.,North University of China
Advanced Materials Research | Year: 2014

Spatial sampling criteria and fast recognition theory based on single view imaging system are proposed for automatic testing the assembly structures inside products in industry applications. There must be a maximum rotary step for an object within which the least structural size to be tested is ascertained. Rotating the object by the step and imaging it and so on until a 360°turn is completed, an image sequence is obtained that includes the full structural information for recognition. It is verified that objects could be recognized at a single or some limited orientations by analyzing the correlations among the image sequence. The theory is applied to the online automated X-ray vision system. Experiments show that the average identification takes less than 5s with 4.5% of wrong recognition expense. © (2014) Trans Tech Publications, Switzerland.


Zhang Z.,National Key Laboratory for Electronic Measurement Technology | Zhang Z.,North University of China | Wang W.,North University of China
XXI IMEKO World Congress "Measurement in Research and Industry" | Year: 2015

The paper presents a kind of idea of determining uncertainty of frequency response based on dynamic calibration principles. The paper gives an example of pressure transducer which uncertainty of frequency response is determined by experimental data of multi-time dynamic calibration. It is crucial for widening operational frequency band-width of transducer concerned in the process of inverse filtering or correcting dynamic characteristics in practical applications.


Zhang Z.,National Key Laboratory for Electronic Measurement Technology | Zhang Z.,North University of China | Li Y.,North University of China
XXI IMEKO World Congress "Measurement in Research and Industry" | Year: 2015

The main cause of dynamic errors is due to limitation of sensor's working frequency bandwidth. One way of solving this problem is designing an effective inverse filter. The method based on Particle Swarm Optimization (PSO) integrated with Functional Link Artificial Neural Network (FLANN) for correcting dynamic characteristics of sensor is presented to reduce sensor's dynamic error caused by its systems limitation. The feasibility of dynamic compensation method is tested, Simulation results from simulator of sensor show that the results after being compensated has given a good description to input signal.


Han Y.P.,National Key Laboratory for Electronic Measurement Technology | Li R.H.,North University of China
Applied Mechanics and Materials | Year: 2014

One photoelectrical test method and system were optimal developed for messuring the optical performances of some scintillation crystals. The theoretical Critical Focal Length of the measurement system is firstly deduced and used in order to make the most of both X-ray photons and the effective area of the scintillation crystal panel. Furthermore, coaxial cable ordered is used to replace the carried wire to weaken power noise. Finally, a low-pass filter with 35Hz upper limit cut-off frequency is designed to reduce spike interference of high-frequency noise. Experiments are successfully done to comprehensive test the spectral response, conversion efficiency and spatial resolution of some scintillators, and the results show that the presented system in this paper is helpful to test the scintillator properties. © (2014) Trans Tech Publications, Switzerland.


Zhen C.,North University of China | Liu W.,National Key Laboratory for Electronic Measurement Technology | Liu Y.,North University of China | Yan A.,North University of China
International Journal of Distributed Sensor Networks | Year: 2014

Both energy-saving and synchronization issues are the paramount concern in wireless sensor networks (WSNs). In this paper we propose a simple and efficient WSN node design based on acoustic positioning applications and present an on-demand sleep/wake scheduling synchronization protocol. Three aspects are already considered in the design: (a) power controllable; (b) energy efficient; (c) high synchronization accuracy. Our primary goal is to maximize energy saving and to control power supplying according to environments and demands. We establish a model of energy consumption and improve it by the ways of power control and on-demand synchronization. The on-demand synchronization protocols are implemented in sensor nodes and evaluated in a testbed. Analysis and simulation were performed that the proposed protocol has significantly reduced the energy consumption. It is also demonstrated by experiments that the platform is accurate and effective. © 2014 ChengFang Zhen et al.

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