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A Naturalness-Preserved Low-Light Enhancement Algorithm for Intelligent Analysis

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Chinese Journal of Electronics 2019年第2期28卷 316-324页

作者： ZHUO Li HU Xiaochen LI Jiafeng ZHANG Jing LI Xiaoguang Signal & information processing laboratory Beijing University of Technology Collaborative Innovation Center of Electric Vehicles

Images/videos captured in low-light conditions often present low luminance and *** the existing low-light enhancement algorithms can improve the subjective perception, color distortion and over-enhancement are extremely obvious, which will disturb the subsequent intelligent analysis. Therefore,a naturalness-preserved low-light enhancement algorithm for intelligent analysis is proposed in this paper. An enhancement model is established in RGB color *** of ColorChecker color chart are captured under a series of light conditions. To preserve the naturalness,the factors of the proposed enhancement model are estimated by the images captured in practical illumination environment. Experimental results demonstrate that the proposed algorithm can produce natural enhanced results and improve the performance of vehicle license plate localization and skin color detection compared to the existing algorithms. Furthermore, the proposed algorithm can process the 720p videos at the speed of 28.3 fps on average.

关键词： Low-light enhancement Intelligent analysis Naturalness-preserved Vehicle license plate localizations Skin color detection

Phase-feld Study for Texture Evolution in Polycrystalline Materials under Applied Stress

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Journal of Materials Science & Technology 2013年第10期29卷 999-1004页

作者： Yanli Lu Liuchao Zhang Yingying Zhou Zheng Chen Jianguo Zhang State Key lab of Solidifcation processing Northwestern Polytechnical University

The formation and evolution of deformation texture in polycrystalline materials are studied by phase-field dynamic model. In addition, the driving force of texture evolution is also discussed. In this model, grains with different orientation are defined by a set of continuous non-conserved order parameter fields. Simulation results show that grains with preferred orientation grow at the expense of those with unfavorable orientations. It is more important that, elastic potentia evolution of texture whether the polycrystalline system rather than elastic energy plays a crucial role in the s subjected to uniaxial stress or shear stress.

关键词： DS: Deformation texture Polycrystalline Applied stress Phase-field model

Predicting compositional time series via autoregressive Dirichlet estimation

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Science China(information Sciences) 2018年第9期61卷 300-305页

作者： Ganbin ZHOU Ping LUO Qing HE Key lab of Intelligent information processing of Chinese Academy of Sciences Institute of Computing TechnologyChinese Academy of Sciences University of Chinese Academy of Sciences

In recent years,compositional time series(CTS)prediction has become a widely applied data analysis method for modeling tactile sequence data[1],hydrological time series data using a four-

关键词： CTS Predicting compositional time series via autoregressive Dirichlet estimation

Adaptive Backstepping Slide Mode Control of Pneumatic Position Servo System

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 1003-1009页

作者： REN Haipeng FAN Juntao Shaanxi Key laboratory Complex System Control and Intelligent information processing Xi'an University of Technology

With the price decreasing of the pneumatic proportional valve and the high performance micro controller, the simple structure and high tracking performance pneumatic servo system demonstrates more application potential in many fields. However, most existing control methods with high tracking performance need to know the model information and to use pressure sensor. This limits the application of the pneumatic servo system. An adaptive backstepping slide mode control method is proposed for pneumatic position servo system. The proposed method designs adaptive slide mode controller using backstepping design technique. The controller parameter adaptive law is derived from Lyapunov analysis to guarantee the stability of the system. A theorem is testified to show that the state of closed-loop system is uniformly bounded, and the closed-loop system is stable. The advantages of the proposed method include that system dynamic model parameters are not required for the controller design, uncertain parameters bounds are not need, and the bulk and expensive pressure sensor is not needed as well. Experimental performance, as compared with some existing methods. results show that the designed controller can achieve better tracking

关键词： pneumatic position servo system adaptive backstepping design slide mode control uncertain parameter tracking accuracy

Immune particle swarm optimization of linear frequency modulation in acoustic communication

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Journal of Systems Engineering and Electronics 2015年第3期26卷 450-456页

作者： Haipeng Ren Yang Zhao Shaanxi Key laboratory of Complex System Control and Intelligent information processing Xi'an University of Technology

With the exploration of the ocean, underwater acoustic communication has attracted more and more attention in recent years. The underwater acoustic channel is considered to be one of the most complicated channels because it suffers from more serious multipath effect, fewer available bandwidths and quite complex noise. Since the signals experience a serious distortion after being transmitted through the underwater acoustic channel, the underwater acoustic communication experiences a high bit error rate （BER）. To solve this problem, carrier waveform inter- displacement （CWlD） modulation is proposed. It has been proved that CWlD modulation is an effective method to decrease BER. The linear frequency modulation （LFM） carrier-waves are used in CWlD modulation. The performance of the communication using CWID modulation is sensitive to the change of the frequency band of LFM carrier-waves. The immune particle swarm optimization （IPSO） is introduced to search for the optimal frequency band of the LFM carrier-waves, due to its excellent performance in solving complicated optimization problems. The multi-objective and multi- peak optimization nature of the IPSO gives a suitable description of the relationship between the upper band and the lower band of the LFM carrier-waves. Simulations verify the improved perfor- mance and effectiveness of the optimization method.

关键词： underwater acoustic communication carrier waveform inter-displacement (CWlD) multi-objective optimization immune particle swarm optimization (IPSO).

Binaurality and azimuth tuning of neurons in the auditory cortex of the big brown bat

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Chinese Science Bulletin 2002年第12期47卷 1024-1027页

作者： SHEN Junxian & CHEN QicaiCenter for Brain and Cognitive Science, laboratory of visual information processing, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China Department of Biology, Central China Normal University, Wuhan 430070, Center for Brain and Cognitive Science Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China Department of Biology Central China Normal University Wuhan China

By using a combined closed and free-field stimulation system, binaurality and azimuth tuning of the neurons in the auditory cortex of the big brown bat, Epte-sicus fuscus, were studied. A variety of azimuth-tuning functions were demonstrated for the binaural neurons. The large majority of EE (contralateral and ipsilateral excitatory) neurons exhibited azimuth selectivity with the best azimuths (BA) at contralateral 30°-40°, some at ipsilateral 20°-40° and preferred azimuth ranges (PAR, response amplitude >75% of maximum) between 8° and 40°. Sound source azimuths strongly modulate spike counts with a mean modulation depth of 83.8% for EE neurons. EI (contralateral excitatory and ipsilateral inhibitory) neurons have simple azimuth tuning with BA located at contralateral 20°-40° and a broad PAR ranged from 30° to 55°. The present results suggest that azimuth-tuning characteristics of binaural neurons in the auditory cortex of the bat are of significance for acoustic behaviour.

关键词： bat auditory cortex binaural neurons azimuth tuning.

Analysis of weak signal detection based on tri-stable system under Levy noise

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Chinese Physics B 2016年第6期25卷 85-94页

作者：贺利芳崔莹莹张天骐张刚宋莹 School of Communication Chongqing University of Posts and Telecommunications Key laboratory of Signal and information processing of Chongqing

Stochastic resonance system is an effective method to extract weak ***,system output is directly influenced by system *** at this,the Levy noise is combined with a tri-stable stochastic resonance *** average signal-to-noise ratio gain is regarded as an index to measure the stochastic resonance *** characteristics of tri-stable stochastic resonance under Levy noise is analyzed in ***,the method of generating Levy noise,the effect of tri-stable system parameters on the potential function and corresponding potential force are presented in ***,the effects of tri-stable system parameters w,a,b,and Levy noise intensity amplification factor D on the resonant output can be explored with different Levy ***,the tri-stable stochastic resonance system is applied to the bearing fault *** results show that the stochastic resonance phenomenon can be induced by tuning the system parameters w,a,and b under different distributions of Levy noise,then the weak signal can be *** parameter intervals which can induce stochastic resonances are approximately ***,by adjusting the intensity amplification factor D of Levy noise,the stochastic resonances can happen *** bearing fault detection,the detection effect of the tri-stable stochastic resonance system is superior to the bistable stochastic resonance system.

关键词： tri-stable system Levy noise stochastic resonance bearing fault detection

Frequency Selective Propagation by Employing Fabry-Perot Nanocavities in a Subwavelength Double-slit Structure

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Chinese Physics Letters 2012年第4期29卷 217-220页

作者： M.Afshari Bavil SUN Xiu-Dong HUANG Feng Optical information processing Group Department of PhysicsHarbin Institute of TechnologyHarbin 150001

By embedding a nanocavity adjacent to one or both of slits in a subwavelength double-slit structure,frequency selective propagation through the slits is *** the incident light wavelength corresponds to the cavity resonance mode,the electromagnetic wave passing through the slit will be trapped within the ***,the double slit operates as a single slit and light propagation is solely allowed through the partner *** wavelengths are determined by applying the Fabry Perot resonance condition for the *** geometrical structures result in different effective refractive ***,the effective refractive index and consequently the attenuation wavelength can be adjusted by choosing the appropriate parameters of the *** theoretical predictions are in good agreement with 2D finite-difference time-domain simulation.

关键词： refractive cavity double

Experimental analysis of sea clutter using airborne circular scanning SAR in medium grazing angle

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Journal of Systems Engineering and Electronics 2019年第1期30卷 68-77页

作者： PAN Xueli LIAO Guisheng YANG Zhiwei DANG Hongxing National laboratory of Radar Signal processing Xidian University Academy of Space Electronic information Technology

The theoretical statistical model of sea clutter is a key issue for maritime surveillance. In recent years, the statistical model of sea clutter has attracted much attention to design the detector well. Meanwhile, the circular scanning synthetic aperture radar(SAR) has been applied to wide surveillance of the sea ***, the paper analyzes the validity of available sea clutter models for range Doppler images from different scan angles for moderate sea state in the medium grazing angle. The parameter estimation method for different distribution models employs the method of logarithmic cumulant(MoLC) based on Mellin transform uniformly. By the analysis of the fitting performance between the histogram of real data and the amplitude probability density function(PDF) of empirical distribution models and the goodness-of-fit(GoF) test for real data from different scan angles, it is indicated the generalized K(GK) distribution with generalized Gamma texture distribution can fit the sea clutter well for different scan angles in the medium grazing angle.

关键词： range Doppler image method of logarithmic cumulant (MoLC) Mellin transform generalized Gamma distribution.