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Liu J.,Northeastern University China | Liu J.,Shenyang Academy of Instrumentation Science | Wu Z.,Northeastern University China | Li Y.,Northeastern University China | Lu D.,NEUNN Technology Co.
Proceedings of the World Congress on Intelligent Control and Automation (WCICA) | Year: 2015

Pipeline transportation is the main way of crude oil and product oil transportation, pipeline leak detection and positioning in time is very important to safe operation of the pipeline. The currently existing leak detection methods based on negative pressure wave are consider the interference existing in steady oil transportation state as random disturbance, which cause the difficult to detect tiny leak. But the existing studies have proved that when the oil transportation is steady, the pipeline the pressure shows the chaotic characteristics. In this paper, according to the chaotic characteristic in oil pipeline transportation, we design a oil pipeline leak detection methods, in which the algorithm adopts the combination of median and wavelet filter method, anomaly detection based on RBF neural network and fuzzy min-max classification method. At last we give the structure of pipeline leak detection system, in which the proposed leak detection method is the key method. © 2014 IEEE. Source

Tang C.,Northeastern University China | Zhang Y.,Northeastern University China | Zhao G.,Northeastern University China | Ma Y.,Shenyang Academy of Instrumentation Science
Chinese Journal of Mechanical Engineering (English Edition) | Year: 2014

The existing researches of the evaluation method of ride comfort of vehicle mainly focus on the level of human feelings to vibration. The level of human feelings to vibration is influenced by many factors, however, the ride comfort according to the common principle of probability and statistics and simple binary logic is unable to reflect these uncertainties. The random fuzzy evaluation model from people subjective response to vibration is adopted in the paper, these uncertainties are analyzed from the angle of psychological physics. Discussing the traditional evaluation of ride comfort during vehicle vibration, a fuzzily random evaluation model on the basis of annoyance rate is proposed for the human body's subjective response to vibration, with relevant fuzzy membership function and probability distribution given. A half-car four degrees of freedom suspension vibration model is described, subject to irregular excitations from the road surface, with the aid of software Matlab/Simulink. A new kind of evaluation method for ride comfort of vehicles is proposed in the paper, i.e., the annoyance rate evaluation method. The genetic algorithm and neural network control theory are used to control the system. Simulation results are obtained, such as the comparison of comfort reaction to vibration environments between before and after control, relationship of annoyance rate to vibration frequency and weighted acceleration, based on ISO 2631/1 (1982), ISO 2631-1 (1997) and annoyance rate evaluation method, respectively. Simulated assessment results indicate that the proposed active suspension systems prove to be effective in the vibration isolation of the suspension system, and the subjective response of human being can be promoted from very uncomfortable to a little uncomfortable. Furthermore, the novel evaluation method based on annoyance rate can further estimate quantitatively the number of passengers who feel discomfort due to vibration. A new analysis method of vehicle comfort is presented. © Chinese Mechanical Engineering Society and Springer-Verlag Berlin Heidelberg 2014. Source

Jiang Y.,CAS Changchun Institute of Optics and Fine Mechanics and Physics | Jiang Y.,University of Chinese Academy of Sciences | Sun Q.,CAS Changchun Institute of Optics and Fine Mechanics and Physics | Liu Y.,CAS Changchun Institute of Optics and Fine Mechanics and Physics | Zhao L.-X.,Shenyang Academy of Instrumentation Science
Guangzi Xuebao/Acta Photonica Sinica | Year: 2013

In order to stabilize the optical performance influenced by the temperature changes, an optical seeker with conformal dome on the basis of the passive optical athermallization method is discussed. Reasonable materials are chosen correctly according to athermal equations. The hybrid refractive-diffractive configuration is introduced for the design of athermal optical system design.Ellipsoidal conformal dome could optimize the aerodynamic performance and reduce the heating of the missile dome.missile dome heating. Inverted telephoto triplet is helpful to acquire short focal length and wide FOV. It is shown that an optical system with ±90° unvignetted FOR, F/2, 100% cold stop efficiency was present. A back focal length of 22.8 mm is large enough for the cooled detector, and also MTF are higher than 0.4 at the spatial frequency of 15 lp/mm across the entire field with the working wavelength at 3~5 μm. The specifications can satisfy the requirements of precise seeker, which can ensure the compact design of the system. Source

Yan M.,Shenyang Academy of Instrumentation Science
Advanced Materials Research | Year: 2013

Mainly introduce the work principle of Dicing Saw and the different kinds of errors in assembly, analyze all errors which influence LCD glass; draw the picture according to the measuring data, from the picture estimate the errors how to come from and prove that the judgments is true through calculating the rigidity of liner bearing; find the source of the main error, appoint out how to take measures for the errors and what is the key point in the assemble. This errors analysis method of the applied mechanics play an important role in other Dicing Saw assemble and test. © (2013) Trans Tech Publications, Switzerland. Source

Tang C.-Y.,North University of China | Zhao G.-Y.,North University of China | Zhang Y.-M.,North University of China | Ma Y.,Shenyang Academy of Instrumentation Science
Research Journal of Applied Sciences, Engineering and Technology | Year: 2012

In this study, a fuzzy logic control design is represented for the control of an active suspension system. A seven degrees of freedom non linear full vehicle model is established, instead of two degrees of freedom one quarter model and four degrees of freedom half body model and the road roughness intensity is modeled as a white noise stochastic process. Then a fuzzy logic controller is designed for the control of the seven degrees of freedom full vehicle model, the input variables are the suspension displacement and the output variables are the control force. The time responses of the full vehicle model are obtained, not only the vertical body acceleration, but also the roll angular acceleration and pitch angular acceleration. Finally, uncontrolled and controlled cases are compared. With the aid of software Matlab/simulink, simulation process is done. Simulation results indicate that the proposed active suspension system proves to be effective in the vibration isolation of the suspension system both in ride comfort and in stability. © Maxwell Scientific Organization, 2012. Source

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