Loading...

Table of Content

15 January 2011 Volume 24 Issue 1
  
    Articles
    Removal of Multiplicative Noise by the Adaptive Fidelity Term
    ZHAO Zhi-Long, LIU Hui, ZHANG Huan
    . 2011, 24(1):  1. 
    Abstract ( 1855 )   PDF (1039KB) ( 1430 )  
    References | Related Articles | Metrics

    Multiplicative noise,unlike the standard Gaussian additive noise,often appears in synthetic aperture radar and sonar and laser imaging.The multiplicative noise agrees with Rayleigh and Gamma functions.This paper converts the multiplicative model into an additive one by taking logarithms,changes the standard TV regularizer into an adaptive fidelity term diffusion model and applies mathematical models into multiplicative imaging denoising.The model can not only remove noise but also enhance edges.

    Fractal Fusion for More Spectral Visible Light Images and High-Resolution Panchromatic Images
    HE Long-Bing, NA Yan
    . 2011, 24(1):  4. 
    Abstract ( 1558 )   PDF (936KB) ( 1042 )  
    References | Related Articles | Metrics

    A more spectral visible light image and High-resolution Panchromatic image fusion algorithm based on the HIS,wavelet transformation and fractal dimension is developed for the domain of remote images.First,the remote panchromatic images and the component I of the remote multi-spectral image are decomposed to the domain of the wavelet transformation which has the advantage of good directions,and the remote image fusion is then implemented in different subbands.The  region energy fusion algorithm is adopted as fusion rules in low-pass subbands.In high-pass the fractal feature of every pixel is calculated by adding a size of 21×21 of window,and then images of high-pass are merged with different fractal dimension of every pixel as weight.Finally,the stretched grayscale fused image replaces the original intensity component,and the final fused image is achieved.The experimental results show that,the use of the fractal feature to determine the scale of the two source image in the fused image can effectively hold the edge and textures of the two original images,and avoid the vague phenomenon in the distributions.The fused image is easier to identify and has more volume.Therefore,the algorithm of IHS and wavelet fractal raised in this paper is effective and can achieve better results.

    Texture Image Analysis Based on Discrete Fourier Transform and Permutation Entropy
    LUO Yuan-Jun, YE Xue-Mei, FAN Qing-Gang
    . 2011, 24(1):  9. 
    Abstract ( 1648 )   PDF (668KB) ( 1082 )  
    References | Related Articles | Metrics

    As the texture feature output has superior performance in image classification,a method based on discrete Fourier transform and permutation entropy is proposed.The method of principal components analysis is adopted to reduce the dimension of the eigenvector.The Support Vector Machine(SVM) is used to classify the texture image.The results show the methods perform well in texture image classification.

    Application of Ray Tracing in Ionospheric Sounding
    GUO Wan-Zhen, YUN Guang-Peng
    . 2011, 24(1):  12. 
    Abstract ( 1400 )   PDF (1078KB) ( 938 )  
    References | Related Articles | Metrics

    By processing the data of ionosphere detection we obtain the model of ionosphere,which is asymmetric in the horizontal direction.The method of ray tracing is used in the model of asymmetric ionosphere.The step-changing technology is used in the ray tracing of the equator two-humped model.The asymmetry of electron concentration and index of refraction in the direction of horizontal is well reflected by the path of the ray tracing,which is valuable in ionosphere oblique sounding.

    Design of Applications Program Online Upgrade Based on ARM7
    ZHAO Wei, YIN Ting-Rui
    . 2011, 24(1):  16. 
    Abstract ( 1755 )   PDF (591KB) ( 1028 )  
    References | Related Articles | Metrics

    This paper introduces the application of ARM7 IAP function based on the NXP's LPC2138 chip.By introducing the communication protocol used for download,this paper presents the application program field download process problems which need to be noticed.Finally,it describes the implementation process of the whole download program.The experimental results show that the design is reasonable,stable and reliable.

    Research on the Construction of the Digital Campus Information Service Platform
    WU Lin, ZHANG Yu-Zhen
    . 2011, 24(1):  19. 
    Abstract ( 1305 )   PDF (487KB) ( 950 )  
    References | Related Articles | Metrics

    A fundamental change in the traditional operation mode of universities and the digital campus information service platform is an inevitable trend for the management and development of modern universities.This paper presents the composition,core function and major advantages of the construction of the digital campus information service platform with a specific university as an example in the hope of enabling the teaching and management to be information oriented,digital and network oriented gradually.

    Study of Docking Between the Rfid-sim Card Mobile Phone and Campus Application Systems
    CHEN Xian-Ting, JIA Xiao-Fei
    . 2011, 24(1):  22. 
    Abstract ( 1660 )   PDF (466KB) ( 1033 )  
    References | Related Articles | Metrics

    Data integration is an important element in the construction of campus information and a necessary condition for making full use of campus resources.On the basis of the authors' experience in the project construction for campus rfid-sim card mobile phone applications and docking between systems,this paper analyzes the relationship between campus data and proposes a method for docking between systems.Campuses under or ready for construction of the rfid-sim card mobile phone can benefit from this paper.

    Data Acquisition for Deep Space VLBI
    WU Jian-Wei, CHEN Wen-Quan
    . 2011, 24(1):  24. 
    Abstract ( 1674 )   PDF (754KB) ( 1103 )  
    References | Related Articles | Metrics

    Deep space exploration relies on the high precision aerospace measurement means.However,the measurement system available in China can not meet the need of deep space exploration.The deep space exploration system in development is provided with VLBI,which has the unique ability of high precision angle measurement.Owing to the long distance between various stations,the VLBI system needs to send the acquired measurement data to related processing centers so as to obtain the measurement results.The data acquisition system,which is a key technology for VLBI measurement,needs to be further studied.

    The Implementation of High Precision Sine and Cosine Functions on FPGA
    WANG Wei
    . 2011, 24(1):  28. 
    Abstract ( 1992 )   PDF (763KB) ( 1029 )  
    References | Related Articles | Metrics

    Based on the study of the CORDIC algorithm,this paper uses pipeline processing to implement the CORDIC in hardware,which meets the requirement of real-time processing and high precision.Software simulation and hardware experiment have been done for this module on Altera FPGA.The wide angle even above 360° can also be supported by the hardware module.The accuracy of most of the data is up to 10-9,and the clock frequency reaches 233.2 MHz.The results show that the module has high accuracy and good stability.

    An Algorithm for 3D Direction-Finding Crossing Location in Multi-Station
    LIU Li-Nan, ZHAO Xiao-Meng
    . 2011, 24(1):  35. 
    Abstract ( 1504 )   PDF (865KB) ( 973 )  
    References | Related Articles | Metrics

    A new data fusion approach is given for the 3-D multi-station measurements.This method first picks two stations in n observation stations to gain a rendezvous result,then introduces one kind of weighting operation to fuse the two station rendezvous results and obtains a new localization method.Finally simulation and performance analysis are carried out.The simulation result indicates that the new algorithm increases the localization precision,avoids the iterative starting value selection,guarantees the localization method's validity and reduces the work load.

    Modeling and Simulation for the Spatial Distribution Characteristics of Chaff Cloud
    XU Jin-Ping, MEI Yong-Hua, YANG Pei, ZHANG Heng
    . 2011, 24(1):  38. 
    Abstract ( 1475 )   PDF (641KB) ( 989 )  
    References | Related Articles | Metrics

    The technique of chaff cloud is an important part of electronic warfare.In the modern aeroamphibious operations,the chaff bombs play an important role in terms of covering airplanes,naval ships,sites and establishments etc.The research of chaff cloud's RCS is an indispensable factor to evaluate the chaff bombs' jamming effects.This paper analyzes the spatial distribution characteristics of chaff cloud and establishes two mathematical models,the globosely symmetrical distribution model and globosely asymmetrical distribution model.Computer simulation verifies the correctness of the models.

    A Tracking Algorithm Based on the Movement of Mobile Objects
    LI Jin-Ming
    . 2011, 24(1):  41. 
    Abstract ( 1635 )   PDF (460KB) ( 948 )  
    References | Related Articles | Metrics

    Based on the tracking of mobile objects by mobile base stations,this paper detects,extracts,identifies and tracks the trajectory of moving objects and obtains the movement parameters of moving objects as well as the trajectory of moving objects.The parameters are further processed and analyzed in order to understand the behavior of moving targets and complete more high-level tasks.

    The Design of a High-Speed Data Transmission System Based on Gigabit Ethernet
    ZHANG Cheng, LUO Feng
    . 2011, 24(1):  44. 
    Abstract ( 2134 )   PDF (549KB) ( 938 )  
    References | Related Articles | Metrics

    This paper introduces the Gigabit Ethernet interface and TCP/IP,proposes several schemes for building a Gigabit Ethernet.A method of using FPGA and Triple Speed Ethernet MegaCore to build a Gigabit Ethernet is presented.Experiments prove that this method is good in stability,high in bandwidth and low in additional cost.It is applicable for most systems which require high-speed data transmission.It is a good solution with low cost,high bandwidth and good stability for high-speed data transmission.

    Reinforcement Learning Model,Algorithms and Its Application
    ZHAN Zhong-Li, WANG Qiang, CHEN Xian-Ting
    . 2011, 24(1):  47. 
    Abstract ( 1702 )   PDF (479KB) ( 5794 )  
    References | Related Articles | Metrics

    Reinforcement Learning does not need prior knowledge,and it gets optional policy through trial and error,its capacity of self-improving and online learning is one of the basic technologies of intelligent agent.In the paper,we firstly introduce the model and foundation of RL,then,we deeply discuss the main algorithms of RL,including Sarsa,temporal difference,Q-learning and function approximation,finally,we briefly introduce some applications of RL and some future research direction.

    A Filling Heuristic Algorithm for the Two-dimensional Rectangle Packing Problem
    YANG Cai-Jun, ZHANG Yu-Ping
    . 2011, 24(1):  50. 
    Abstract ( 1256 )   PDF (570KB) ( 921 )  
    References | Related Articles | Metrics

    The packing problem of cutting the optimal layout of small rectangles on a pallet is considered.Combining the ant algorithm with the simulated annealing algorithm,a mixed new algorithm of layout optimization,which is implemented by the lowest horizontal and filling algorithm,is proposed in this paper.In order to investigate the computation,numerical tests with randomly generated instances are carried out.By comparison,the solutions show the robust effectiveness of this approach.The results show that this approach achieves a better effect.

    Design of a Telemetry Signalsimulate Source Based on FPGA and LabView
    WANG Xiao-Guang, LIU Fang
    . 2011, 24(1):  52. 
    Abstract ( 2213 )   PDF (698KB) ( 1246 )  
    References | Related Articles | Metrics

    Specialized equipment is designed by FPGA and LabView to test telemetry components.LVDS signals with a variable transmission rate are realized by the DDS technology and the interactive interface of the digital signal source is achieved by using the LabView graphical programming tool.The computer controlled LVDS signal with a variable transmission rate and variable data content can,therefore,be produced.

    The Design of Digital Quadrature Coherent Detection for the DBF System
    YANG Ling, YANG Yang, LIU Gui-Yu
    . 2011, 24(1):  55. 
    Abstract ( 1656 )   PDF (590KB) ( 1151 )  
    References | Related Articles | Metrics

    The theorem of band passing signal sampling is discussed with some examples in engineering,on the basis of which the optimized design of the digital quadrature coherent detection is studied.Computer simulations performance analysis shows that this design is useful to other engineerings.

    A Technique of EM Modeling and Analysis of High Frequency Passive Elements
    XUE Chuan, LIANG Cong, ZHANG Xiao-Dong, HU Shan-Wen, GAO Huai
    . 2011, 24(1):  59. 
    Abstract ( 2447 )   PDF (1177KB) ( 1061 )  
    References | Related Articles | Metrics

    This paper presents the electromagnetic full-wave method to simulate and analyze the passive elements on GaAs substrates to derive the equivalent circuit models of the MIM capacitor,square planer inductor and Microstrip,which are used in a π matching network.All important high-frequency effects which influence the electronic characteristic of passive elements such as lossy substrates,nonuniform current distribution due to skin and proximity effects are considered in these models.Three passive elements are fabricated based on the GaAs technology and testing results show that the derived parameters of EM simulation are in excellent agreement with the measured data from 0.1 GHz to 40 GHz.The circuits simulation results using the EM models for passive elements will be closer to the actual results after tape-out than using the empirical element models.This method not only increases MMIC design accuracy,but also shortens the design time and cuts the design cost.

    Analysis of the Insertion Loss of the EMI Filter
    HUA Rui-Xia, ZHANG Lei, LONG Hui
    . 2011, 24(1):  65. 
    Abstract ( 1577 )   PDF (626KB) ( 997 )  
    References | Related Articles | Metrics

    Based on the equivalent circuits of common-mode and differential-mode for the genetic EMI filter,this paper analyzes the effects of the source and load impedances on the insertion loss of filters in detail.A method to calculate the insertion loss of common-mode and differential-mode is presented.This paper derives the relation between insertion loss of the EMI filter and the impedance.The simulation of this relationship is discussed.Results have verified the correctness of the theoretical calculation and analyses.

    An AMTI Method Based on the Estimation and Compensation of the Clutter Doppler Phase
    HAN Dong, TANG Jian-Long
    . 2011, 24(1):  68. 
    Abstract ( 1405 )   PDF (477KB) ( 935 )  
    References | Related Articles | Metrics

    This paper provides an algorithm of automatic adaptive clutter suppression in the absence of a clutter map and clutter cancellation coefficients.First,the algorithm uses double thresholds to determine the clutter positions of a frame of signals.Then the range cells which contain clutter are compensated by Doppler phase compensation coefficients which are picked out by the minimum power rule.Finally,the moving clutters are cancelled by using the optimal Doppler phase compensation coefficient.Simulation shows that the method can effectively suppress moving clutter and detect the target submerged by clutter.

    Anti-Jamming Simulation Platform for Radar Signal Processing
    YANG Shao-Hua, DU Bai-Sheng
    . 2011, 24(1):  71. 
    Abstract ( 1470 )   PDF (565KB) ( 1329 )  
    References | Related Articles | Metrics

    The intermediate frequency complex signal,which includes the linear frequency modulation signal,noise,clutter and jamming,is simulated by related algorithms.Then the complex signal is sent to a receiver which is approximate to a linear one.Finally,using various kinds of radar signal processing,we obtain the effect of signal detection under different jammings.The whole task can be an integrated simulating platform and provides convenience for evaluating the effect of jamming.

    Application and Improvement of Velocity Precision in Monopluse Tracking Radar
    KONG Xiao-Dan, ZHANG Lin-Rang, LUO Feng
    . 2011, 24(1):  74. 
    Abstract ( 2009 )   PDF (598KB) ( 1274 )  
    References | Related Articles | Metrics

    The traditional monopulse radar uses FFT in tracking speed to realize the moving target detection module.This method may lead to a relatively large Doppler error because of the low frequency resolution.This paper proposes a Doppler frequency deviation method using the principle of low and high filter and the method of accurate calculation,which significantly increases frequency resolution and improves speed measuring precision.The computer simulation results and the field test results indicate that this method is effective.This method has been applied in a monopulse tracking radar system.

    Research on Airspace Surveillance of Phased Array Radar Based on Time Division Techniques
    SHENG Si-Jia, LIU Peng, ZHOU Qing-Feng, YANG Pei
    . 2011, 24(1):  78. 
    Abstract ( 1719 )   PDF (962KB) ( 918 )  
    References | Related Articles | Metrics

    Based on airspace surveillance and time division techniques of phased array radar,this paper introduces the basic application methods and special cases on airspace search of phased array radar.The application methods of airspace target tracking are presented in terms of normal tracking,different data rates tracking,multi-channel tracking and angle tracking,which have been tested by experiments.

    A New Multipath Scattering Model of Rough Surface
    Li Yan
    . 2011, 24(1):  81. 
    Abstract ( 1441 )   PDF (940KB) ( 1018 )  
    References | Related Articles | Metrics

    To improve the tracking precision of low-angle radar,it is necessary to consider multi-path effect caused by reflection of the earth.In this paper,a new model of multi-path scattering considering surface roughness,masking effect and multiple scattering respectively is presented based on the facet model whose scattering coefficient is derived based on the Kirchhoff theory.Signals from various rough surfaces based on various wavelength are computed.The pertinence of direct and echo signals is analyzed.

    The Research on the Novel Transmission Line CRLH-TL
    ZHANG Pei, CHENG Guang-Wei
    . 2011, 24(1):  86. 
    Abstract ( 1418 )   PDF (456KB) ( 993 )  
    References | Related Articles | Metrics

    According to the basic theory of the transmission line and the specific nature of the left-handed materials,CRLH-TL is constructed.The propagation characteristics of CRLH-TL is systematically summarized,and a complete design of microstrip is offered from a practical point of view.HFSS simulation results show that the structure presents the characteristics of LH at low frequencies and characteristics of RH at high frequencies,and has the features of width band,low loss,small size and so on.

    The Design and Realization of the Basic Signal Generator Based on SOPC
    NI Liang, WU Li-Min, ZHAO Peng-Fei
    . 2011, 24(1):  89. 
    Abstract ( 1819 )   PDF (1304KB) ( 1005 )  
    References | Related Articles | Metrics

    This paper introduces a basic signal generator based on the SOPC design technology.In order to achieve the basic signal generator,the design of system hardware circuit takes EP1C6Q240C8of Altera Corporation as the hardware core,embeds the soft-core CPU into FPGA-chip,and unifies the memory circuit,high-speed DAC circuit,LCD circuit,the keyboard circuit,JTAG configuration circuit,the power circuit and so on.The paper describes the main module design and gives some pictures for hardware and software test.Through the oscilloscope observation,system design requirements are met and the desired objectives are achieved.

    Characteristics of 555 Timer's Function and Application
    LI Chun-Ling
    . 2011, 24(1):  93. 
    Abstract ( 1145 )   PDF (552KB) ( 893 )  
    References | Related Articles | Metrics

    This paper deals with the 555 timer's function,and introduces a simplified model which is highly memorable.It also probes the characteristics of its applied circuits,such as astable multivibrator,monostable multivibrator and bistable multivibrator.

    IEEE 1394b High-speed Data Transfer System Based on FPGA
    XUN Jian-Hui, LI Yu-Shan, CHANG Xu-Xi
    . 2011, 24(1):  96. 
    Abstract ( 1764 )   PDF (841KB) ( 948 )  
    References | Related Articles | Metrics

    This paper introduces the new features of the IEEE 1394b serial bus,and designs a 1394b high-speed data transfer system by using the embedded processor Nios II as the control core.Emphasis is put on the principle of hardware design and software flow pattern.Experiments show that the system has the advantages of high reliability,good real-time performance and practicability.

    Application of Ultrasound in the Six Degree-of-freedom Measurement Positioning System
    LIU Xin-Feng, LI Zhong-Ke
    . 2011, 24(1):  99. 
    Abstract ( 1661 )   PDF (494KB) ( 1145 )  
    References | Related Articles | Metrics

    In view of the fact that simulation of tooth arrangement needs coordinate information,this article describes a six-degree-of-freedom measurement based on the ultrasonic positioning system principle and design.This system obtains data by measuring 7 times at the 3 points on the three-dimensional coordinate,and processes them in real time with a single-chip microcomputer.Experiment results show that the accuracy of this system meets the actual needs,and is appropriate for manual operation.This system can be easily transferred to other occasions where six-degree-of-freedom parameters are needed.

    Research on the Fault-Tolerant Techniques Based on Dynamic Reconfigurable FPGA
    ZHANG Chao, LIU Zheng, ZHAO Wei
    . 2011, 24(1):  102. 
    Abstract ( 1359 )   PDF (982KB) ( 959 )  
    References | Related Articles | Metrics

    This paper analyzes several methods in the aspects of size of reconfigurations,reconfiguration interval,implement complexity,inter-module communication,routing and proportion of spare resources.To solve some main problems,we have proposed a method based on the multiple division of algorithm and resources and analyzed its performance.This method is flexible and some parameters like granularity are optional.Routing of reconfiguration is reliable and can ensure the operation frequency of the system.

    Design of an I/F Conversion Circuit
    LIU Shu-Kai
    . 2011, 24(1):  106. 
    Abstract ( 1332 )   PDF (423KB) ( 1013 )  
    References | Related Articles | Metrics

    This paper introduces the design of an I/F conversion circuit with a single supply.This circuit comprises two OPA2335AID,a TS5A23166 whit VHB comparator,a CMOS Switch,etc.It can convert a 4-20 mA current signal or 1-5 V voltage signal into a 10~50 kHz square wave.With a 3-5 V single supply used,the linearity of output can reach up to +0.1% FS.This circuit has a simple structure,stable output  and good linearity.

    Study on Timeliness of Crude Oil High-frequency Viscosity Reduction
    WEI Ai-Jun, JIN Xin-Tao, MEN Feng-Yin
    . 2011, 24(1):  109. 
    Abstract ( 1510 )   PDF (517KB) ( 903 )  
    References | Related Articles | Metrics

    Through the processing of treating crude oil with high-frequency to reduce viscosity of crude oil,then study the relationship between the viscosity reduce of crude oil and the time away from high-frequency treatment.Then change the time and current of the treatment.We compare the results when they come out.By this way we proved the high-frequency treatment can reduce the viscosity of crude oil.Meanwhile we study the timeliness of the high-frequency effect and find out the best treatment conditions to provide the follow-up study an important reference for.

    Single-phase Grounding Fault Analysis and Study of Line Selection for the Small Current Grounding System
    YANG Shu-Ying, ZHANG Xiao-Ming
    . 2011, 24(1):  112. 
    Abstract ( 1442 )   PDF (538KB) ( 984 )  
    References | Related Articles | Metrics

    This paper analyzes several common malfunctions in case of singlephase grounding for the low current grounding system,presents the methods for fault identification and countermeasure for grounding malfunctions,on the basis of which it studies single phase wire selection for the low current grounding system.Experiments show that this system can identify fault accurately and giving an alarm.

    The Effects of CBC on the Nonlinearity of the HBT Power Amplifier
    DING Jie, HU Shan-Wen, ZHANG Xiao-Dong, GAO Huai
    . 2011, 24(1):  115. 
    Abstract ( 1904 )   PDF (852KB) ( 990 )  
    References | Related Articles | Metrics

    GaAs HBT is one of the main technologies for designing monolithic microwave power amplifiers (PAs).The capacitor between the base terminal and collector terminal CBC is the dominant nonlinear element in HBT PAs.This paper analyzes the law of variation of HBT CBC with circuit bias using the Gummel-Poon transistor model,and presents the tendency of CBC to vary with input power.Simulation results based on AWR Microwave Office show that the main reason for the PAs′ amplitude and phase distortion is that CBC increases with the rise of the input signal power.Circuit design and testing verify the correctness of the theoretical analysis and simulation.

    A Novel Dual-Layer Microstrip Directional Coupler
    RAN Tao, FU Guang, FAN Yi-Peng
    . 2011, 24(1):  118. 
    Abstract ( 1623 )   PDF (607KB) ( 983 )  
    References | Related Articles | Metrics

    A novel dual-layer microstrip directional coupler is presented.The directional coupler consists of two-layer,back-to-back substrates with a couple aperture.By increasing the coupling proportion and introducing parasitical part to compensate the capacitance and poise the odd mode and even mode,it realizes tight coupling at a wide band.The directivities of the coupler is better than that of the general microstrip ones.The insertion losses,return losses and isolation are better than 0.5 dB,-23 dB and 20 dB over the bandwidth (450~860 MHz),respectively.The measurements agree well with the simulations.

    Research on the Present Situation and Development of Commercial Electromagnetic Simulation Softwares
    FAN Jie-Yi, GAO Cheng
    . 2011, 24(1):  121. 
    Abstract ( 1628 )   PDF (466KB) ( 980 )  
    References | Related Articles | Metrics

    Different electromagnetic simulation softwares have different theories,structures and applications.This article examines more than 30 kinds of commercial electromagnetic simulation softwares,comparatively analyzes their characteristics,advantages and disadvantages in order to seek the development trend for commercial electromagnetic simulation softwares.

    E-book with a Combination of Digital Library
    ZHANG Wan-Li
    . 2011, 24(1):  124. 
    Abstract ( 1306 )   PDF (494KB) ( 941 )  
    References | Related Articles | Metrics

    This paper discusses the information carrier transformation to the human significance,and reveals the ebook and informationization of the development trends and characteristics of library,points out the ebook and digital library combining the inevitability and many advantages.

Download

Monthly,Founded in September 1987
Competent Authorities:
Ministry of Education of the People's Republic of China
Sponsored by:Xidian University
Chief Editor:Liao Guisheng
Executive Editor:Wan Liancheng
Editor:Hei Lei
Editor and Publisher:
The Editorial Department of Electronic Science and Technology
Distribution Abroad:
China Intermational Book Trading Corporation
P.O.BOx 399,Beijing 100044,China
Address:
P.O.Box 375,2 Taibai Road(South),Xi'an 710071,China
Tel/Fax:0086-029-88202440
Website:http://www.dianzikeji.org
E-mail:dzkj@mail.xidian.edu.cn
Unit Price:$20.00