Table of Content

15 July 2015 Volume 28 Issue 7

  

Articles

Clutter Reduction in Ground Penetrating Radar Signal Based on Wavelet Transform and Ridgelet Transform[BT)]

YU Haiyan

. 2015, 28(7):  1. 

Abstract ( 528 )   PDF (819KB) ( 445 )  

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A clutter reduction method based on wavelet transform and ridgelet transform for ground penetrating radar signal is proposed.Wavelet transform can express images of point singularities with the best approximation.Ridgelet can express images of straight edges with sparse coefficients perfectly.Firstly the random noise is suppressed by an adaptive threshold denoising method,combined with the characteristics of wavelet transform and ridgelet transform.Then the direct wave is removed from the ridgelet domain by employing the directional sensitivity of the ridgelet transform.The efficiency of the algorithm has been demonstrated by processing practical GPR data.

Signal Processing System of PD Radar and Its Implementation

LIAN Zhiling

. 2015, 28(7):  5. 

Abstract ( 597 )   PDF (644KB) ( 473 )  

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As a classic radar signal processing method,pulse-doppler (PD) processing is widely used in all kinds of radar.A real-time radar signal processing system is designed,which uses the range segmenting method and parallel processing of multiple DSPs technique based on eight pieces of ADSP-TS201.Real data are processed with this method,indicating that the proposed method,which has been put into practical use,makes better use of the board resources and improves the system efficiency.

An Avian Target Detection Radar Based on Coherent-on-Receive

WANG Shengguo,KONG Fan,WU Xiafei,ZHANG Lin

. 2015, 28(7):  8. 

Abstract ( 528 )   PDF (913KB) ( 563 )  

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For the urgent demand of the avian target detection technology,effective prevention of the hazards of aircraft take-off and landing caused by birds,a technical solution for the avian target detection radar based on coherent-on-receive is proposed.Firstly,through the analysis of avian target detection radar history and birds actual flight attitude,the system architecture and technical approaches are studied.Then the key technologies are analyzed,and the coherent-on-receive technology is studied by engineering practice in the application of avian target detection radar.Experimental data prove the feasibility of the scheme,which provides reference for the next step engineering applications.

Design and Implementation of Stable System for the Signal Source of Calibration Tower

WU Xin,DAI Guangming,WEI Zhongliang,WANG Leilei

. 2015, 28(7):  12. 

Abstract ( 444 )   PDF (894KB) ( 450 )  

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In the process of the outfield calibration of radar,the position of the signal on the tower is changed by the wind disturbance within dozens of millimeters.Calibration accuracy of the Rader is influenced by the change of the signal position.A stable system with the laser tracker and two-dimension stable platform as the core is designed to resist the disturbance of the wind.The laser tracker is used to measure the position of the signal in time.Then the two-dimension stable platform is used to stabilize the signal position with the calculated compensation position.Experimental results show that the system has advantages such as high position stabilization accuracy,fast response speed.Great position stabilization accuracy is achieved better than 0.5 mm in 0.2 s.Favorable safeguard for the outfield precision calibration is provided by the stable system.

Application of Visualization Technology in Radar Reconnaissance Signal Processing

DONG Chuangang,LIU Weirong

. 2015, 28(7):  15. 

Abstract ( 566 )   PDF (659KB) ( 552 )  

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The acquisition of accurate radar parameters in electronic reconnaissance data processing is an important subject.The development of visualization technology is introduced in this paper,and the application of visualization technology in radar reconnaissance signal analysis is discussed.Finally,a human-computer interactive analysis of radar signal processing on the Visual Studio 2010 platform is simulated.The result proves the feasibility of visualization technology applied in radar reconnaissance signal processing.

Pulse Generation and Radiation Based on On-off LC Oscillators and Electrically Small Antennas

GUO Lisheng,WANG Xin,HE Jinmei

. 2015, 28(7):  18. 

Abstract ( 533 )   PDF (758KB) ( 424 )  

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A novel pulse transmission circuit has been proposed based on electrically small antennas and on-off LC oscillator.The electrically small antenna serves no only as the radiating element,but also as part of the LC oscillator.The on-off state of the transistor within the oscillator determines the stability of the system.As the transistor is turned on by an external control voltage,a short-pulse signal is generated.Simulation and measurement results show that a 6 Vpp signal across the electrically small antenna can be obtained under the 1.4 V bias voltage,and a power efficiency of as high as 24.3% can be achieved.

Design of an FDTD Parallel Program with Dispersive Medium Based on OpenMP

LIU Jun,ZHAO Zhiqin

. 2015, 28(7):  21. 

Abstract ( 488 )   PDF (547KB) ( 456 )  

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This paper presents the model of dispersive medium in FDTD and the PLRC method for unmagnetized plasma.The basic models of OpenMP paradigm is introduced and applied to unmagnetized plasma computation.The accuracy of the OpenMP parallel program when applied to dispersive medium is proved by testing the transmission wave through the unmagnetized plasm,and the high performance of the program is proved by three cases with different sizes of computational regions.

Design of a Bandgap Circuit with Sectional Curvature Compensation

LI Jilei,GUAN Jinzhou,YANG Hua

. 2015, 28(7):  24. 

Abstract ( 474 )   PDF (592KB) ( 456 )  

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This paper presents a novel design approach for sectional curvature compensated reference circuit.The one-time curvature compensated reference circuit can only make the temperature coefficient of the reference voltage generated at a temperature 0,and in the entire temperature range the temperature coefficient is large.We propose herein a sectional curvature compensated reference circuit design method,so that the reference voltages generated at a plurality of temperature points have a zero temperature coefficient and the stability of the reference voltage can be improved.The circuit design is based on the 0.35 μm CMOS process.Cadence simulation shows that the design goals are attained.

A Novel Reconfigurable Coupling Feed Dipole Antenna

XIE Qianqian,ZHOU Yonggang,OUYANG Weizhong,LI Bonan

. 2015, 28(7):  28. 

Abstract ( 475 )   PDF (801KB) ( 424 )  

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A novel reconfigurable proxy-coupled printed dipole antenna array is presented.The radiation pattern can be switched by controlling the distance of each dipole and distance between every dipole and the main feed line.The antenna array can form dipole antenna array nesting arrangement of different radiation patterns,and can transfer to different dipole radiation elements via pin switch,leading to the reconfiguration of the radiation pattern and diversity of maximum radiation direction.The simulation results show that the antenna can obtain the maximum radiation direction at 0°and 40° at the center frequency of 9.8 GHz,and the maximum gain is 12 dBi at 0° and 8.7 dBi at 40°;the input reflection coefficient under either working state is lower than -30 dB,showing a perfect impedance matching.

Modular Design and Automatic Code Generation of PLL

WU Shuai,YANG Wenhuan,CHEN Bin,XIA Minghao

. 2015, 28(7):  31. 

Abstract ( 554 )   PDF (674KB) ( 481 )  

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A new method of three-phase-locked loop controller base on Xilinx System Generator (SG) is presented,which facilitates simulation debugging in Simulink while saving the need for complex code writing.According to the principle of three-phase power phase-locked loop (PLL),the SG Model of PLL is built.The HDL code of this model is generated by SG automatically and imported into an ISE project.The Feasibility of this method of PLL is proved by downloading the bit file generated by ISE into FPGA.

Design of Power Module Based on Address Mapping

ZHANG Qin,XUE Ji,XIE Ming,YING Cheng

. 2015, 28(7):  34. 

Abstract ( 1081 )   PDF (800KB) ( 491 )  

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This article presents a power module which has the function of Modbus address mapping in view of the inefficiency of power module communication currently with emphasis on the address mapping methods by which the customers can read continuous Modbus address mapping area for the discontinuous data register of power module.The practical operation of power module indicates that it can improve the communication efficiency and cut the costs of system construction.

Design of X Band Frequency Source with Low Phase Noise Based on Frequency Multiplier

XIAO Heng

. 2015, 28(7):  38. 

Abstract ( 478 )   PDF (658KB) ( 823 )  

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A design of frequency source is given using the working principle of microwave frequency multiplier in order to obtain a low phase noise X band microwave signal.The circuits of frequency multiplier using BJT and FET are analyzed concretely and debugged respectively.The frequency source achieves a low phase noise with measurement results of -87 dBc@100 Hz,-102 dBc@1 kHz and -110 dBc@10 kHz,showing that the frequency multiplier can hardly add noise other than the theoretic phase noise loss.

Design of a DDR3 Controller Based on FPGA

JIAO Shuhong,CHENG Rentao

. 2015, 28(7):  41. 

Abstract ( 1141 )   PDF (637KB) ( 566 )  

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This paper briefly introduces the characteristics and operating principles of DDR3 and the structure of the controller.A design of the controller is implemented on the Virtex-6 series of FPGA chip using the MIG software of Xilinx.The ISim simulation results verify the feasibility of the design.

Recognition and Graphical Display of Reversible Logic Expressions

ZHANG Le,ZHAO Shuguang,XIAO Huajun

. 2015, 28(7):  44. 

Abstract ( 1037 )   PDF (732KB) ( 698 )  

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The reversible logic circuit is a circuit that contains only reversible operation,and is free from information loss and heat energy.It is also the foundation of and key to the ultra-low power integrated circuits,quantum computers and information security.This paper studies the effective methods and feasible algorithm of extracting the reversible logic circuits structure information and its graphical display by recognizing reversible logic expressions to express the result of synthesis and optimization of the reversible logic circuits,which offers convenient analysis,understanding and optimization of reversible logic circuits.

Design of an Intelligent Electromagnetic Navigation Car Based on Cubic Functions

CAI Yisong,LIU Haigang,XIANG Huazhen,DAI Jinsheng,HUANG Qinglei

. 2015, 28(7):  48. 

Abstract ( 446 )   PDF (791KB) ( 479 )  

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In order to achieve stable and rapid automatic smart car hunt,a "two line and five rows plus a splay" electromagnetic coil arrangement is used to identify a variety of complex tracks.The deviation is obtained by the algorithm of cubic functions and corners are processed using the differential motor algorithm to realize the electromagnetic navigation.Practical applications show that this system achieves precise control of the smart car with fast and stable operation.

Key Technology of Cycle Data Transmission Based on MPC5554

LIU Ming

. 2015, 28(7):  51. 

Abstract ( 497 )   PDF (590KB) ( 424 )  

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The data transfer by a combination of EDMA and SPI methods with scheduling using clock interrupt and query tasks are discussed for cycle data transmission.The data transmission method and scheduling methods used can achieve real-time transmission of large amounts of data while avoiding CPU consumption.Finally,the process of data transmission is illustrated by an example,and the technical advantages and disadvantages are analyzed and discussed.

Design and Implementation of Wide-band Low Phase Noise Frequency Synthesizers

LI Ang,YU Meng,ZHU Kangsheng

. 2015, 28(7):  54. 

Abstract ( 531 )   PDF (778KB) ( 563 )  

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In order to meet the design requirement of the radar signal,this article describe a frequency synthesizer based on the decimal phase locked loop chip GM4704 made in China.The conventional PLL technique is adopted to generate low phase noise signal from 7.12 to 9.12 GHz.The design process and the related design parameters are given.Also we use the PLL simulation to design the loop band filter.Circuit tests show that the phase noise can reach to -97 dBc/Hz@1 kHz,which is close to the theoretical value;the spurious can reach -71 dB.

An Underwater Target Recognition Method Based on Frequency Zoom Technology

QIU Zheng,WANG Feng,PAN Yuanzhang

. 2015, 28(7):  56. 

Abstract ( 1001 )   PDF (815KB) ( 458 )  

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Passive sonar target recognition is realized according to different target radiation noises.The extraction of effective features from the underwater target radiated noise is the key to underwater target recognition.Based on the analysis of the characteristics of the target radiation noise,an improved high frequency noise demodulation (DEMON) method for target extraction of line spectrum is proposed.A distinct DEMON line spectrum is extracted by spectrum DEMON spectrum fusion using wavelet transform,and then purified by the frequency cycle diagram method for reliable line spectrum extraction.Simulation and experimental results verify the validity and feasibility of the proposed method.

Design of Equiripple Array Based on Grating Lobe

MO Zijun,JIAO Longfei

. 2015, 28(7):  60. 

Abstract ( 429 )   PDF (781KB) ( 301 )  

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An outstanding problem of broadband reconnaissance DBF is the serious grating lobe at high frequency band of signal.This paper presents a digital array design based on grating lobe equiripple,that is,the selection of array elements spacing based on the change of the frequency of broadband signal,which proves effective by simulation.

Whole-Speed Range Rotor Position Measuring Method for Permanent Magnet Synchronous Motor Based on DSP

ZHU Jun,TIAN Miao,LIU Huijun

. 2015, 28(7):  63. 

Abstract ( 561 )   PDF (684KB) ( 427 )  

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A method for position detection and initial positioning permanent magnet synchronous motor rotor is developed based on DSP for the precise transformation of coordinate system of motor positions.The improved magnetic localization method is used when motor is stationary,where the rotor is tracked out of the positioning blind spots by outputting DC torque twice,and then fixed to the predetermined position to get the rotor initial position.The improved M/T method is used when motor is running,which uses variable sampling time to measure speed and rotor position information.The experimental based on DSP results show that the method can accurately locate the initial position of the rotor and that the motor can accurately detect the rotor position at low speed and high speed,verifying the reliability and validity of the method.

An Equipment Checking Device Based on the Temporal Logic of Power Supply Interface

LI Leyi,FAN Yu

. 2015, 28(7):  67. 

Abstract ( 488 )   PDF (716KB) ( 493 )  

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At present,the self-test unit of the traditional test equipment covers only channel checks,and can not detect the work temporal logic,which may affect the product's safety testing if the test device timing is abnormal.This paper presents the design and implementation of a checking device for the temporal logic of power supply interface including the design,hardware/software development,and the entire work process and functions.Results show that the checking device greatly improves detection depth,early malfunction elimination and product safety testing.

Suppression of Brushless DC Motor Torque Ripple Inhibition Based on Cuk Converter

SHI Jun,YANG Wenhuan,XIA Tianyu,XIA Minghao

. 2015, 28(7):  70. 

Abstract ( 1151 )   PDF (744KB) ( 453 )  

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In order to solve the large torque ripple of brushless DC motor (BLDCM) transfer in the phase change,we propose the addition of a pre-Cuk converter and a switch selection circuit in front of the three-phase inverter bridge to suppress the torque ripple by controlling the single inverter input voltage.This method maintains equilibrium of the current slopes of the instantaneous commutation current rise and fall phases,thereby effectively reducing the commutation torque ripple.Simulation verifies the feasibility of this method.

Laser Fuze Anti-interference Based on Dual-wavelength Detection

SHI Runlong,MEI Hao,YU Haishan

. 2015, 28(7):  74. 

Abstract ( 504 )   PDF (853KB) ( 489 )  

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In view of the fact that the laser fuze is easy to be interfered by fog and smoke,a method of anti-interference based on dual-wavelength detection is proposed in this paper.The scattering characteristic of single aerosol particle to dual-wavelength laser is researched.The scattering echo both by analysis and measurement are given.Reflectivity of some metal and nonmetal targets to dual-wavelength laser is practically measured.The analytic and experimental results show that the scattering characteristic of fog and smoke particles to dual-wavelength laser are different,while the ratio of backscattering power is usually more than 2.The reflectivity of targets to dual-wavelength laser is nearly the same,while the ratio of reflected power is about 1.Using information of backscattering power ratio in signal processing is a new approach to anti-interference for laser fuze.

Design of a SIP-based Message Waiting Indications Model

SONG Xiuping,GONG Youlong

. 2015, 28(7):  78. 

Abstract ( 487 )   PDF (597KB) ( 390 )  

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For the various requirements of MWI functions of terminals,this article provides a SIP-based MWI model,and implements message simulation on intelligent network platform.The construction of the event notification system is discussed with practical instances.Simulation results prove that SIP MWI is easy in implementation and high in efficiency.

Adaptive Three Dimension Weighted Centroid Localization Algorithm Based on RSSI

DONG Jun,LI Jibiao

. 2015, 28(7):  81. 

Abstract ( 537 )   PDF (595KB) ( 462 )  

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A three dimension weighted centroid localization algorithm with RSSI as the weighted factors is introduced for the poor accuracy of wireless sensor network RSSI weighted centroid localization algorithm.Adaptive narrowing of location areas is performed through RSSI,and a three-dimensional sphere positioning model is constructed according to the selected optimal reference nodes.It is shown by simulation experiments that the improved algorithm achieves better precision and stability than the traditional weighted centroid algorithm.

Performance Comparison Between MMSE and LS Equalization Algorithms for Satellite Channels

LI Xuan,ZHANG Yu,GUAN Qingyang

. 2015, 28(7):  84. 

Abstract ( 609 )   PDF (682KB) ( 484 )  

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OFDM system model is applied to the satellite channel.Considered the actual situation,multipath interference and Doppler shift are added to the channel.In order to eliminate the inter-carrier interference (ICI) and the inter-symbol interference (ISI) better,the equalization algorithm is used after demodulation.The MMSE and LS equalization algorithm are studied in detail.The difference in performance of the two algorithms is concluded and the direction of the equalization algorithm is pointed out.

Two-degree-of-freedom Smith Control for Time-Delay Systems

XIN Fang,HE Jianzhong

. 2015, 28(7):  87. 

Abstract ( 478 )   PDF (679KB) ( 441 )  

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In terms of internal model control (IMC) a two-degree-of-freedom Smith control method is proposed for typical industrial process,and the designed controller has only two adjustable parameters.This method offers the process control system good command tracking and disturbance rejection characteristics.The matlab simulation results demonstrate the effectiveness of the designed controller.

Collaborative Filtering Recommendation Algorithm Based on Social Tags

WANG Baolin,HAN Shuaishuai,ZHANG Dehai

. 2015, 28(7):  90. 

Abstract ( 536 )   PDF (735KB) ( 432 )  

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In order to reduce the noise of the tag-based collaborative filtering algorithm caused by the semantic ambiguity and redundancy of social tags,the popular tags are selected by the wisdom of crowds to profile users and resources.Then a collaborative filtering algorithm is designed based on the popular tags.The experiment shows that the proposed algorithm has reduced the noise of tags and improved the precision of the traditional tag-based collaborative filtering algorithm.

Pattern Recognition of Partial Discharge Based on Wavelet Transform and Probabilistic Neural Network

MA Lixin,SHAN Yu

. 2015, 28(7):  94. 

Abstract ( 1035 )   PDF (716KB) ( 509 )  

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For the small number of samples in the classification of partial discharge pattern in high voltage electrical appliances and the poor recognition rate of conventional classification methods,a mixed algorithm is proposed based on probabilistic neural network hybrid algorithm and wavelet transform.Wavelet decomposition is performed on partial discharge signals in a laboratory simulation with the extracted wavelet energy coefficient as the feature parameter,and as the input of a probabilistic neural network for classification.The obtained results are better than that by the multilayer feedforward neural network (MLP) algorithm and the support vector machine method using sequential learning optimization.

Threat Ordering Method Based on Overall Combat Effectiveness

CHEN Hui,GONG Qi

. 2015, 28(7):  97. 

Abstract ( 508 )   PDF (748KB) ( 425 )  

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Aiming at the deficiency of air target threat ordering method for combat aircraft support,the paper puts forward a threat ordering method based on overall combat effectiveness,establishes the index system of threat ordering,analyses the least bias fuzzy complementary judgment matrix method for calculating the index weights,introduces the improving rate matrix [CX2]Q[CX] of combat capability,and gives the threat degree of support combat targets.The simulation result show that the threat ordering method offer more accurate evaluation of the threat degree of support combat targets and more suitable for the air defense combat practice.

Implementation and Performance Analysis of CLCG4 Parallelization Based on MIC

LI Zhijie,ZHOU Jinyu,HUA Cheng,LIU Xiao,ZHOU Xiaohui

. 2015, 28(7):  101. 

Abstract ( 455 )   PDF (680KB) ( 469 )  

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The CLCG4 generator is a kind of feedback shift random number generator that has wide application for its long period and good randomness,but with low speed in generating random numbers.A parallel algorithm is designed and implemented based on the CLCG4 serial algorithm.Experimental results show that the parallelized CLCG4 generator has a significant increase in speed over the single-thread with the CPU on the MIC platform with a speedup rate of up to 6.82.

K-means Initial Clustering Center Selection Algorithm Based on Density

HAN Lingbo

. 2015, 28(7):  105. 

Abstract ( 541 )   PDF (543KB) ( 431 )  

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The initial clustering center of the traditional K-means algorithm is generated randomly from the data set,and the clustering results fluctuate with the initial cluster centering of different.A new improved K-means algorithm based on density is proposed,by which the density parameter and neighborhood distance of every data object is computed,then k point in high density parameter are chosen as the initial clustering centers.A comparison is made using UCI database as testing datasets with given number of clusters.The clustering results demonstrate that the improved algorithm can enhance the clustering stability and accuracy relatively.

Ranging Compensation Indoor Positioning Based on RSSI

DENG Chang,GUAN Hongyun,ZHANG Hui,HUANG Huidi,XUE Jie

. 2015, 28(7):  108. 

Abstract ( 621 )   PDF (741KB) ( 472 )  

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In view of the environmental factors that affect the traditional RSSI (Received Signal Strength Indication) ranging precision,a ranging compensation algorithm is proposed to compensate the ranging error caused by environmental factors and to handle multiple RSSI values that the same point receives by the mean value smoothing method to reduce the fluctuation of RSSI values.Simulation and field tests verify that the ranging compensation algorithm improves the ranging accuracy.

A Study of Fuzzy Weighted Similarity Measure for Collaborative Filtering Recommender Systems

ZHANG Yake

. 2015, 28(7):  111. 

Abstract ( 486 )   PDF (689KB) ( 477 )  

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In the traditional collaborative filtering algorithm,the calculation of similarity is based directly on user ratings,which are subject to uncertain factors,and thus the user preferences information is inaccurate by Numerical rating.This paper defines several membership functions of fuzzy sets and puts forward the similarity calculation method based on fuzzy logic.The experimental results show that the similarity based on fuzzy weight effectively improves the accuracy of the recommendation system.

Load Balancing Algorithm Based on QoS for Call Admission Control

LIU Junwei,WU Zi'an

. 2015, 28(7):  115. 

Abstract ( 552 )   PDF (719KB) ( 303 )  

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A new admission control algorithm is introduced,which can satisfy the user's preferred service quality,reduce network congestion,and optimize the common interests of users and the network.The simulation results show that this algorithm can balance network load and reduce dropping rates with better user satisfaction.

Virtual Surround Algorithm and IP Core Implementation

LONG Fen,DING Lin

. 2015, 28(7):  118. 

Abstract ( 685 )   PDF (878KB) ( 589 )  

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This paper uses the Prony method based on the head-related transfer functions (HRTF) theory to design a virtual multi-channel playback filter,and employs Verilog description and simulation to develop a better performance of the IP core,which is validated on the Nexys 3 Spartan-6 FPGA platform.Experimental results show that the IP core has high efficiency and good characteristics of spatial effects during playback.

The Realization of DQ BER Eye Diagram Based on Statistical Method

WANG Huailiang,XU Zhihua,YAN Jinrong,LI Yating,JIANG Feng,ZHOU Zixiang

. 2015, 28(7):  124. 

Abstract ( 565 )   PDF (889KB) ( 447 )  

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Following closely from PDA analysis,this project is intended to develop an algorithm that employs single-bit response to forecast eye diagram and BER for a high speed system.With Linear time-invariant (LTI) theorems used regularly,coupling with the statistical signaling,statistical methods are introduced to calculate the BER eye diagram of DQ signal under the influence of inter symbol interference and crosstalk.The results show that fast and effective prediction is achieved,which prepares the ground for further study of the impact on BER of jitter and the uncertainty of the time of receiver judgment.

Crowd Density Estimation Based on Pixel and Texture

WANG Qiang,SUN Hong

. 2015, 28(7):  129. 

Abstract ( 577 )   PDF (1023KB) ( 543 )  

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A crowd density estimation algorithm based on the pixel and texture is proposed.The Vibe algorithm is adopted for foreground extraction with the interested area (ROI) set to reduce the computational complexity.To solve the errors caused by the distance of the crowd,the morphology processing and perspective correction is involved.A standard is introduced to divide the crowd density to overcome the errors induced by changes in the crowd density.The experimental results show that the arithmetic speed and the accuracy are considerable,which verifies the reliability of the algorithm.

Design of a Wireless PM2.5 Concentration Detection System

WANG Hao,KONG Lingrong

. 2015, 28(7):  133. 

Abstract ( 505 )   PDF (725KB) ( 606 )  

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A wireless detection system is designed according to the actual requirements of PM2.5 concentration detection in daily life.An nRF24L01 wireless communication module was used for data transmitting and receiving for the wireless detection of PM2.5 concentration collected by the GP2Y10 sensor.The system is composed mainly of the AT89S52 single-chip microcomputer,the nRF24L01 wireless communication module,the GP2Y10 sensor,and the LCD display module.Test shows that the system works well and meets the requirements of PM2.5 concentration wireless detection.

Research on Image Fusion Based on Multi-scale Transform and Particle Swarm Optimization

NA Yan,WANG Yunpeng

. 2015, 28(7):  137. 

Abstract ( 552 )   PDF (958KB) ( 478 )  

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The image fusion based on multi-scale transform is a hot spot in multi-sensor image fusion.A method of image fusion based on multi-scale transform and particle swarm optimization is proposed in this paper and the impact of the quality of initial images on fusion result is further studied.Experimental results show that the algorithm has better fusion result and using images of large deviation can get better result.

Applications of Extrusion Tread Size Control Based on Image Processing

TANG Xunjun

. 2015, 28(7):  140. 

Abstract ( 516 )   PDF (944KB) ( 248 )  

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The tire tread extrusion machine control system is mostly based on extrusion pressure,and the controlling effect cannot directly reflect the extrusion tread size and make it disqualification sometime.In view of this,this paper presents a fuzzy neural network control method based on image processing,using the edge strengthening threshold algorithm to strengthen extrusion tread image and extract the tread data by feedback control based on the fuzzy neural network analysis.The simulation results show that the method has good control over the screw rotation speed,and effectively extracts extrusion tread size data.

Palmprint Recognition Based on Gabor Wavelets and LLE

XIA Dequn,CHEN Wei

. 2015, 28(7):  145. 

Abstract ( 450 )   PDF (877KB) ( 281 )  

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An algorithm based on Gabor wavelet transform and palmprint recognition locally linear embedding (LLE) is proposed for better extraction of non-linear characteristics.Firstly,region of interest is extracted and preprocessed through filtering and suppression light.Then,the multi-scale characteristics of the palmprint image are obtained by wavelet transform of Gabor and the principal component is extracted by the non-linear LLE algorithm.Finally the nearest neighbor classifier is used to classify the palmprint.The experiment is based on the PolyU palmprint database and compares the effects on recognition rate of the preprocessing,different ROI extraction methods,and the parameters of the LLE algorithm.The experimental results show that this method achieves better recognition rate than both the traditional linear dimension reduction algorithm and the separate LLE algorithm.

Method for Real-time Generation of Virtual Human Animation Based on Kinect

YANG Daotan

. 2015, 28(7):  149. 

Abstract ( 435 )   PDF (974KB) ( 513 )  

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Traditional virtual human animation has some drawbacks including low real-time performance,low realism,complex generation process and high cost.This paper proposes a novel generation approach to virtual human animation based on Kinect.Firstly,it uses the forward kinecmatics method to establish the skeleton model with topology structure,and then remap the user's skeleton information captured by Kinect to virtual human.Furthermore,it introduces the principle of translation compensation and distortion processing mechanism.The experiment shows the method can provide real-time and realistic virtual human animation,and is easy to realize.

Level Set and its Application in Image Processing

YANG Siyan

. 2015, 28(7):  153. 

Abstract ( 452 )   PDF (948KB) ( 242 )  

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This paper focuses on the basic theory of level set and its applications in image processing.The level set theory and the curves evolving method are discussed in detail,and the applications of level set method in image segmentation,image noise-reducing,image restoration,image registration,3D animation are illustrated.Experimental results show that a more accurate and robust image processing result can be achieved using the level set method than by the typical algorithm when complex forms and obvious topologic change are involved.

General Data Acquisition and Transmission System Design in Perception Layer

WEI Xuesong,SUN Wanrong,WANG Leilei,YUE Zhijia,WANG Danyu

. 2015, 28(7):  157. 

Abstract ( 496 )   PDF (841KB) ( 278 )  

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A new design is introduced for a general data acquisition and transmission system based on ARM9.The S3C2440A is used as the hardware platform,and embedded Linux operating system as the software platform.Various kinds of interfaces are connected with sensors to acquire data and CAN bus and an Ethernet is used to transmit data.The type and number of sensors that connected with the system are not constant,and are added or deleted by PC dynamically.So,the system can be applied in common occasion.

Application of DC Speed Control System in Belt Conveyor Based on PLC

MA Beibei,CHEN Yunqi

. 2015, 28(7):  161. 

Abstract ( 465 )   PDF (716KB) ( 241 )  

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In view of the unsafe coal production with low transport rate,an improved fuzzy-PID speed control system is proposed combining the S7-200PLC and 590+digital DC speed controllers.The hardware structure model of the system is clear and the software uses the closed-loop fuzzy-PID method combined with fuzzy rules to control DC motor.Experiments show that the system has good disturbance resistance,wide speed range and precise control.

Vehicle Stability Research Based on Fuzzy Sliding Model Control

ZENG Fenglin,CHEN Jiaqi

. 2015, 28(7):  165. 

Abstract ( 537 )   PDF (802KB) ( 295 )  

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In view of the vehicle stability handling caused by cornering or path changing,a 3-DOF nonlinear vehicle dynamic model is built.The yaw rate and sideslip angle are employed as the main state variables.Direct yaw moment is used to control the yaw rate and the sideslip angle by sliding model control based on fuzzy control theory.This paper also presents a new method for estimating the sideslip angle based on the recursive least squares (RLS) algorithm,considering the sideslip angle is hard to measure.The simulation results based on Matlab and ADAMS indicate that the yaw rate and sideslip angle can trace the desired ones,and can keep vehicles in safety.

Research on Excitation of Torsional Mode in Pipes Based on the Piezoelectric Sensor

MAO Yadong,ZHANG Wei,YAN Youqi

. 2015, 28(7):  169. 

Abstract ( 545 )   PDF (923KB) ( 277 )  

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Modal unity and attenuation characteristics are important indicators of the incentive effects of guided wave.A guided-wave excitation system is established in which the PZT-5 wafers are symmetrical distributed at one end of the pipeline.In order to reduce the modal unity and attenuation characteristics,experiments have been conducted to study the effect of PZT wafer and modal characteristics on the T(0,1) mode.The optimal scheme to excitation of T(0,1) mode is obtained.

Design of Flight Control System for Small UAV Based on Xilinx Vivado HLS

ZHANG Zhan,CUI Jinwei,LU Jiong

. 2015, 28(7):  172. 

Abstract ( 465 )   PDF (809KB) ( 934 )  

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Aiming at the great difficulty and trivial processes in FPGA development,a fast development method of flight control system based on FPGA is proposed,which introduces Xilinx Vivado HLS development tool and designs the flight control system on the ARM platform.The code is transplanted to the FPGA platform,achieving a complete quadrotor attitude balance system.Application results show that compared,the proposed method offers superior to the traditional FPGA technologies for its simple processes and easy implementation.

An Aircraft Gyro Information Acquisition System

FENG Bin,HE Jianzhong

. 2015, 28(7):  175. 

Abstract ( 1042 )   PDF (709KB) ( 394 )  

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A gyro information collection system is designed to address the instability and low accuracy of the aircraft data acquisition system.The system uses a Kalman filter to obtain stable attitude data.The features and overall structure of the system are introduced,and the hardware design and software acquisition system implementation are given.Spacecraft attitude data collection and analysis are performed by LabVIEW simulation.Tests show that the acquisition system improves the stability and precision of attitude data,and meet the requirements of the acquisition system.

Quantitative Analysis of Goos-Hanchen Effect on the Seismic Reflection of P Waves

YUAN Longgang,FA Lin

. 2015, 28(7):  179. 

Abstract ( 467 )   PDF (649KB) ( 242 )  

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The influence of the Goos-Hanchen effect on the P wave normal time lag is studied using reflection wave phase derived from the lateral offset of P wave in the reflector and the lateral offset transit time.Results show that for incident wave or when the incident angle in the vicinity of the critical angle,the Goos-Hanchen effect P of wave is obvious.So in the actual seismic data processing,error correction of the lateral offset effect should be made.

Research on the Line Laser Hand-eye Calibration Method

WANG Yingnan,DAI Shuguang

. 2015, 28(7):  183. 

Abstract ( 604 )   PDF (558KB) ( 490 )  

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When the line laser is mounted on the multi-joints robot,the relative position between the two is uncertain.To solve this problem,a hand-eye calibration method is adopted to measure a fixed point with different poses and calculate the rotation and translation matrices.A standard ball is used to find the precise fixed point with the centre of the ball as the point.The experiments show the method is feasible and efficient.

Grid Enterprise Information Security System

GE Yuanpeng,CAI Xiaoming,ZHOU Sheng,HUANG Taining

. 2015, 28(7):  186. 

Abstract ( 563 )   PDF (731KB) ( 527 )  

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This article focuses on the enterprise information security system construction based on the current situation of power grid corporations.An information security system framework covering whole process management and all-round protection is built.The whole process management involves the following six parts:planning and design,development and testing,implementation and go-live,support and maintenance,system operation,and system retirement.The all-round protection covers physical protection,boundary protection,server protection,terminal protection,application protection,and data protection.This system can effectively cope with the security maintenance of ever larger information systems.