Table of Content

15 March 2011 Volume 24 Issue 3
    Chaotic Digital Image Encryption and its Hardware Implementation Based on DSP Technology
    XU Xiao-Yun, YU Si-Min, XU Li-Guo
    . 2011, 24(3):  1. 
    Abstract ( 1653 )   PDF (1161KB) ( 1184 )  
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    A novel method for realizing chaotic digital image encryption and its hardware implementation based on DSP is presented.By the discrete and digital process technology,the three-dimensional Lorenz chaotic system is made discrete and Lorenz chaotic iteration sequence is generated by using Hardware Description Language C and DSP technology.Red,green,and blue tricolor signals of the image are encrypted and decrypted,respectively.On the basis of the DSP exploitation platform with TMS320VC5509A chip,a gray image with an   BMP format is taken as an example.The digital image encryption and decryption algorithm using Lorenz chaotic sequence is designed,and DSP hardware implementation result is given.

    Research on and Development of the Arcgis-Based Management System for Electronic Meteorological Display
    LIU Xiao-Dong, YANG Cheng-Rui
    . 2011, 24(3):  6. 
    Abstract ( 1777 )   PDF (648KB) ( 1037 )  
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    The Shaanxi meteorological electronic display management system integrates a variety of meteorological information service products and the electronic display screen.Based on the ArcGIS technology and the graphical operation mode,the system is developed and the objective to manage the meteorological electronic display of Shaanxi Province systematically is achieved.

    Image Reconstruction Technique Based on the Compressed Sensing Theory
    CHEN Meng-Xin, LIU Wen-Bo
    . 2011, 24(3):  9. 
    Abstract ( 1544 )   PDF (1066KB) ( 1260 )  
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    Through the study of the CS theory,this paper realizes the accurate reconstruction of the one-dimensional signal and two-dimensional image by applying the OMP algorithm,which is the classical method in the CS engineering application.As to the problems that large storage of sampling matrix is needed when sampling and calculating the whole image and that a huge amount of time is consumed when reconstructing it,this paper proposes an improvement scheme based on the OMP algorithm,that is,dividing the image into small macro-blocks.The simulation results show that the quality of reconstructed images has been improved without increasing the complexity and the problems above are solved.

    Design of the Intelligent Data Acquisition System for the Pointer Instrument
    WANG Yi, ZHAO Jing, WEN Shi-Xiang
    . 2011, 24(3):  13. 
    Abstract ( 2220 )   PDF (753KB) ( 1369 )  
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    The system designed with the ADSP-BF533+FPGA EP1C6T144C8 architecture achieves such functions as image acquisition,target identification and meter reading,and USB transmission.DSP processes the collected image gray-scale transformation,edge detection and Hough transform to achieve recognize the pointer instrument dial,position the pointer,calculate the reading,and store and transmit the pointer reading.The system can achieve network measurement and data transmission using the RS485 bus.FPGA receives DSPs instructions to acquire and control the COMS camera,scan the keyboard and generate other device chip-select signals.Using the SQLSERVER database technology programs for the host computer,the measured data can be managed and backed up.

    Data Handling and Information Mining of Personnel Statistics
    LIU Ying
    . 2011, 24(3):  18. 
    Abstract ( 1260 )   PDF (513KB) ( 913 )  
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    Statistics of personnel is one of the vital components of personnel administration.It is also an important information source of human resources management as well as the basis of leaders' decisions.The quality of personnel statistics will directly affect the adjustment of personnel policy and even have an impact on the effect of the personnel system reform.This paper focuses mainly on how to collect and deal with the data of personnel issues,how to acquire effective information and make full use of the information so as to help decision-making and realize the value of personnel statistics.

    Study of Data Disaster Recovery Technology
    HAO Le
    . 2011, 24(3):  20. 
    Abstract ( 1310 )   PDF (463KB) ( 958 )  
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    Data disaster recovery is to establish and maintain an off-site backup data center to protect data against catastrophic events by making use of geographic discreteness.In case of data loss,hardware failure or misuse,the backup data center is immediately connected,so that the application services will not be affected.When earthquakes and other natural disasters occur,the backup data center ensures that historical data is not lost,providing secure and reliable backup protection,and has the ability to quickly recover the data and applications after disaster to ensure business to continue.

    The Extraction Algorithm for the Fire Cannons Jet Trajectory in Colorful Pictures
    SUN Wei-Lu, ZHAO Min
    . 2011, 24(3):  27. 
    Abstract ( 1610 )   PDF (1881KB) ( 1049 )  
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    An extraction algorithm for the fire cannon's jet trajectory in colorful pictures based on the difference of RGB is presented.First,24 directions are scanned under the condition that the start of jet is known to make sure that the jet is in one of the 8 directions of the 米 shape,and then the direction is detected by the two-trace method until a certain threshold condition or the edge of the picture is reached.The result shows that this algorithm can extract fire cannon's jet trajectory accurately and completely even under complex conditions.The algorithm is strongly adaptive.

    Medical Image Fusion Based on Cloud Computing and Content Analysis
    LI Wen-Juan, NA Yan
    . 2011, 24(3):  28. 
    Abstract ( 1587 )   PDF (832KB) ( 1119 )  
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    A content analysis based medical image fusion method with cloud computing is presented.First,to design better cloud inference rules,the contents of two source images are analyzed with histograms.Then rules are designed based on the histograms of CT and MRI images and the target of fusion.Finally,as the two inputs of the inference system,CT and MRI images are fused into a resulting image.Experiment results comparison between cloud computing and fuzzy inference shows that the result of cloud computing can provide more information and less distortion than fuzzy inference.Further more,the 9 gray-level method based on cloud computing performs better than the 3 gray-level method based on cloud computing.

    Research on a Filter System Based on the Netfilter L7-filter
    QI Xing-Cheng, LIU Wen-Bo
    . 2011, 24(3):  31. 
    Abstract ( 1218 )   PDF (767KB) ( 786 )  
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    QQ software filter of the existing router is based on traditional port methods.It cannot forbid QQ to login effectively when QQ login uses the proxy.In order to keep QQ software off-line,this paper analyzes the QQ protocol and propose a new QQ protocol regular expression.Taking the advantage of l7-filter and Netfilter,it solves the problem of the QQ software filter effectively.

    Design of an HLA Based Agent Simulation System
    LI Kai, WAN Xiao-Dong, JING Yan, RAO Ming-Bo
    . 2011, 24(3):  34. 
    Abstract ( 1239 )   PDF (705KB) ( 900 )  
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    HLA has been widely used in the field of military modeling and simulation.With the development of simulation technology,requirements for complexity and intelligence are rising,and problems in HLA-based simulation systems and a new simulation algorithm for agent modeling and simulation are an combination of the agent technology and distributed computation technology.On the basis of the advantage of the two in the use of simulation,this paper combines them,establishes an agent-based object model,and designs a new federate,improving the reusability,interoperability and intelligent of the simulation object model.

    A Steady Image Segmentation Arithmetic Base on the Markov Random Field+
    CHEN Hang
    . 2011, 24(3):  38. 
    Abstract ( 1416 )   PDF (331KB) ( 863 )  
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    Given the low speed calculation of image segmentation of the SA (simulated annealing) algorithm and the problem of double-counting stable pixels,this paper introduces the Iterative (ICM) Model to reduce the computational complexity and improve the calculation speed.

    The Analysis of and Research on the Improvement of Crosstalk in the High Speed Circuit by Termination
    DING Li-Tao, CHU Xiu-Qin, FAN Xin
    . 2011, 24(3):  40. 
    Abstract ( 1455 )   PDF (1020KB) ( 1227 )  
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    This paper adopts several different types of circuit termination for the aggressive line in the two coupled lines,the corresponding signal transmission waveform is simulated by the software Hyperlynx.While suppressing the reflection of the aggressive line,the termination circuit also reduces the signal crosstalk of the victim line,so that the signal quality of transmission in the two coupled lines is improved.Finally,by comparing and studying several groups of data about crosstalk,it analyzes the reason for crosstalk diminution.

    X-band Four-Order Harmonic Mixer and the Improvement of Phase Design
    GUO Hong-Cui, LV Guo-Qiang, CAI Fei
    . 2011, 24(3):  44. 
    Abstract ( 1638 )   PDF (537KB) ( 977 )  
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    This paper introduces the circuit simulation and design of an X-band fourth-harmonic mixer based on the anti-paralleled Schottky diodes pair.It has been found that a gentle variance in the LO power or RF power can lead to a sharp change of the IF signal phase.According to the discovery,the whole system is improved.The test results demonstrate the feasibility and good performance of the improved circuit.

    The Realization of the Demodulation of the Frequency-shift Track Based on DSP
    MIAO Cheng-Wei, CHEN Guang-Wu, GAO Jian-Guo, WANG Li-Ping
    . 2011, 24(3):  47. 
    Abstract ( 1746 )   PDF (469KB) ( 931 )  
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    This paper proposes the FSK signal which receives and demodulates the ZPW-2000A with the dual TMS320F2812 as the core.The forepart samples the FSK signal with the internal A/D of DSP by signal conditioning.The calculation of FFT demodulates the carrier frequency and then Z-FFT calculates the low frequency,and finally through the port of DSP's SPI the two outputs are compared.If they are the same,the signal is output.This design uses a hot standby to improve the reliability of the system.The results show that the system has high frequency resolution and good real-timeness.

    Realization of Dynamical Reconfiguration Control Based on the FPGA Data Stream
    GONG Bei-Bei, REN Ai-Feng, HU Fang-Ming
    . 2011, 24(3):  49. 
    Abstract ( 2128 )   PDF (620KB) ( 953 )  
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    This paper is based on the data stream which is downloaded to FPGA to control the digital circuit.The microcomputer controls the data flow by the genetic algorithm to achieve programming allocation for FPGA and thus self-reconfiguration is achieved and the system is accorded the adaptive,self-organization and self-repairing properties.

    Application of Asynchronous FIFO in Communication Between FPGA and DSP
    HU Bo, LI Peng
    . 2011, 24(3):  53. 
    Abstract ( 1852 )   PDF (696KB) ( 999 )  
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    This article introduces the method of using asynchronous FIFO in communication between FPGA and DSP.The FPGA writes the data into FIFO under the control of the writing clock.After hand shaking with the FPGA,the DSP reads the data through the EMIFA interface.The article gives the detailed codes for asynchronous FIFO and the electric circuits for DSP.It is shown that the application of the asynchronous FIFO method in the communication between FPGA and DSP has the advantages of high transmission speed,stability,reliability and easy realization.

    The Influence of Relativity on the Effects of Sidelobe Canceller
    RAN Xiao-Feng, WEI Qing
    . 2011, 24(3):  56. 
    Abstract ( 1512 )   PDF (601KB) ( 1030 )  
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    The theory of adaptive sidelobe canceller is presented in this paper.Effects of coherent coefficient on the sidelobe canceller are studied,and simulation is conducted on a computer by Matlab.The performance results between sidelobe cancellation and the correlation are verified explicitly.It is proved that the increase of relativity can degenerate the cancellation performance and weaken the effect.

    An Extractive Algorithm of Radar True Target Tracking Data Used for the Training Simulator
    MA Hui-Ping, XIANG Hai-Fei
    . 2011, 24(3):  59. 
    Abstract ( 1249 )   PDF (551KB) ( 811 )  
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    Given the limitation of radar searching and tracking training with a simulative target,an extractive algorithm of radar true target tracking data is designed,which has been used in a training simulator of a radar equipment.It can make full use of the test flying data from the radar equipment and process the radar searching and tracking training afterwards.

    Analysis and Simulation on the Noise Jamming of TRAD
    HAN Jin-Ping, RAN Xiao-Feng
    . 2011, 24(3):  62. 
    Abstract ( 1418 )   PDF (605KB) ( 963 )  
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    TRAD(Towed Radar Active Decoy) becomes a most efficient way against radar-guided missile,and it plays an important role in ECM field.Two kinds of jamming style belonging to TRAD are simply recited;secondly four kinds of noise jamming model are mainly analyzed.Then,the error changing curves of the decoy is analyzed between forward jamming and noise jamming style;the paper detailed simulates and analyzes that the decoy brings in effects to the single-pulse radar seeker in four kinds of noise jamming model,and assesses the jamming effect.

    The Study of Power Distribution Network Based on Multiple Input Impedance
    ZHOU Yong, DUAN Guang-Yi
    . 2011, 24(3):  66. 
    Abstract ( 1265 )   PDF (642KB) ( 980 )  
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    This paper depicts accurately the contemporary high-speed plane power distribution network (PDN) through multiple input impedance.This impedance can simultaneously detect inputs of multiple excitation source,which can accurately measure the impact of other port on PDN.Multiple input impedance is a novel input impedance,which have two forms: multiple input self-impedance and multiple input superposed impedance.The former is used to describe each power port within the same IC,and the latter is used to describe the influence between different IC.Time-domain and frequency-domain simulation shows that multiple input impedance can accurately measure the local and global properties of plane power distribution network.

    Comparison of Calibration Methods in the Measurement of Target Characteristics
    YANG Pei, ZOU Yong-Jie, KANG Peng
    . 2011, 24(3):  69. 
    Abstract ( 1243 )   PDF (660KB) ( 1033 )  
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    This paper describes the calibration sphere method and signal calibration method.It analyzes and compares the differences between the two methods based on the calibration accuracy,the complexity of test facilities,weather conditions and other aspects of impact and provides a reference for the choice of RCS tests.

    Evaluation of the Efficiency of the Phased Array Radar System Based on the Theory of Center of Gravity of Cloud
    GU Jia-Chen, ZHANG Hong-Wei, QI Li, SHENG Si-Jia
    . 2011, 24(3):  73. 
    Abstract ( 1110 )   PDF (525KB) ( 878 )  
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    The principle of setting a radar system's efficiency evaluating index is given based on the characteristics of the radar system.A system of index on radar system's comprehensive evaluating is built.Using the theory of center of gravity of cloud,this paper builds a cloud model on the character index and index of both character and quantity.Then,the center of gravity of multidimensional weighted cloud is calculated.A comprehensive evaluation of the efficiency of the phased array radar system is given,using the method of evaluating the center of gravity of cloud.

    Design of a Tri-Band Antenna Array for the MIMO System
    HU Guo-Qing, LIU Ying, GONG Shu-Xi, ZHANG Wei-Dong, ZHANG Ning
    . 2011, 24(3):  76. 
    Abstract ( 1928 )   PDF (547KB) ( 881 )  
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    A low-profile antenna array for multiple-input-multiple-output (MIMO)-enabled wireless communication terminals is introduced.The chosen planar inverted-F antennas (PIFAs) which are etched on a compact board with dimensions of 100×60 mm2 are intended to operate at the following frequency bands: 885-915 MHz,1 760-1 870 MHz and 2 450-2 510 MHz.In order to obtain a very compact system,the distance between the PIFAs is severely reduced to less than a half wavelength (12 mm=0.036λwhen the antenna work at 0.9 G).This leads to another problem: the mutual coupling between PIFA antenna array elements is too high.To improve the isolation between the two closely packed antennas,two methods are proposed.One is to use a suspended neutralization strip which is inserted and physically connected to the antenna elements to improve isolation.The other is to use FR4 and simple round plane modification to reduce coupling.The simulation results show that a 15 dB mutual coupling is obtained over the operating bandwidth without affecting the radiation patterns obviously.

    Application of the Support Vector Machine in the Terminal Guidance Radar of Anti-jamming
    ZHANG Zhao-Hui
    . 2011, 24(3):  79. 
    Abstract ( 1688 )   PDF (627KB) ( 928 )  
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    In order to eliminate the decoy targets caused by various jamming,the support vector machine adopted in the target fusion recognition is presented to solve the multi-dimension feature data fusion problem in active-passive composite terminal guidance radar.Through a quantitative analysis of the feature of jamming aimed at the terminal guidance radar,the parameters including the RCS,the scale of range dimension,Doppler width of the active radar,and the output of the passive radar detection with feature signal are selected,and then fused adopting the support vector machine.The simulation result shows that only using the active radar feature,the recognition ratio of the true-false targets testing sample is 74%.The recognition ratio is increased to 83% by using the active and passive radar feature simultaneously.

    The Design of a Temperature Testing System Based on GSM
    CAI Xu, PEI Zhi-Lei, LU Chao
    . 2011, 24(3):  83. 
    Abstract ( 1739 )   PDF (691KB) ( 896 )  
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    In order to meet the actual needs of remote temperature monitoring,a temperature measuring system based on the GSM module TC35i is presented.The system has STC89C52 as the main chip and  DS18B20 as the temperature acquisition part.Together with the features of TC35i,the temperature data can be sent  to mobile phone users in the form of text messages.The system can replace the manual method and detect temperature at any time.

    The Research on the Design of the Asynchronous Motor Control System Platform
    SHEN Jun-Yi, LUO Wen-Guang, YANG Cheng-Wu, HU Hai-Xu, XIE Rong-Xian
    . 2011, 24(3):  87. 
    Abstract ( 1611 )   PDF (678KB) ( 952 )  
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    The general motion control system chip has few resources and a slow processing speed,and it is therefore difficult for bigger signals to be processed in real time.Such chips can not meet the requirement on the application of the high performance AC speed control strategy and the advanced control algorithm in asynchronous motors.This research and development is based on the asynchronous motor control system development platform with DSP TMS320F2812 and CPLD as the core of control.Using this platform,the development and application of the motor control system product can be completed rapidly.This article introduces the design of hardware and software development method.The system has strong extendibility,flexibility and practicality.

    Adaptive MLSE Algorithm in Rayleigh Fading Channels
    WANG Yin
    . 2011, 24(3):  91. 
    Abstract ( 1199 )   PDF (468KB) ( 877 )  
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    Considering the effects of multipath and Doppler frequency shift in the digital mobile communication,the paper establishes a time-varying Rayleigh fading channel model and uses the maximum likelihood sequence detection algorithm to achieve equalization.Its basic idea is to insert the channel estimation algorithm into the MLSE algorithm,and then track and update the changes of the channel continuously.To lower complexity,this paper studies the conventional adaptive MLSE and per-survivor processing MLSE algorithm.Simulation shows that when the Doppler frequency shift is small,the two algorithm has similar performance with the former less complex.

    Solution for Multi-sensor Optimize Assignment Based on Ant Colony Algorithm
    CHEN Peng-Bo, NA Yan
    . 2011, 24(3):  94. 
    Abstract ( 1562 )   PDF (606KB) ( 856 )  
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    Considering both the effect of priority of target in such transducer management problems as classification,target testing and tracing and the information gain produced by object identification and threat assessment,a new objective function is constructed.By analyzing the problems existing in the allocation of multi-sensor target optimization,an ant colony algorithm model is advanced.Simulation shows the validity of the model.

    Study of Spectrum Sensing Algorithms in the Cognitive Radio Network
    QIAN Feng
    . 2011, 24(3):  97. 
    Abstract ( 1588 )   PDF (642KB) ( 1369 )  
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    The spectrum sensing algorithms,a key technology of cognitive radio,are studied based on domestic and international researches.Several common classical algorithms and the recent series of improved new algorithms are summarized.The advantages and disadvantages of each algorithm are compared.New prospects of future researches are presented.

    The Comparison of the LCS Algorithm with the GST Algorithm in Strings Similarity Metrics[
    YU Hai-Ying
    . 2011, 24(3):  101. 
    Abstract ( 1513 )   PDF (587KB) ( 892 )  
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    The concept,implementation and efficiency of the LCS algorithm and GST algorithm in strings similarity metrics is introduced.The applications of the two algorithms are briefly discussed.

    Research on the Three-level SVPWM Inverter Based on TMS320LF2407
    LI Zheng-Xua
    . 2011, 24(3):  104. 
    Abstract ( 1219 )   PDF (831KB) ( 869 )  
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    This paper focuses mainly on the control method of neutral-point voltage balancing in the three-level inverter.A comprehensive mathematic model of three-level inverter is set up.A novel space vector modulation algorithm is proposed by using the nearest three vectors as the reference voltage vector.The judging rules of the small sectors and the out voltage vector sequence are presented.The duty time of each vector is also computed.The main factors for the neutral-point imbalance are discussed.A simple neutral-point voltage balancing control method,which only requires the direction information detection of each phase leg's current and neutral point voltage ripple,is proposed.The validity of the proposed method is demonstrated by the experimental results.

    An EAP-TTLS Based 3G-WLAN Integrated Network Authentication Method
    SHEN Lei
    . 2011, 24(3):  108. 
    Abstract ( 1955 )   PDF (695KB) ( 916 )  
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    Based on the 3GPP's 3G and WLAN integration program and the false AP attack in the EAP-AKA as well as the user security issues such as disclosure of private information,an EAP-TTLS-AKA authentication method is presented.This method implements the establishment of the UE authentication of the WLAN access network.The AKA authentication of 3GPP and UE is achieved in the drying tunnels.The results show that this method is an effective solution to the false AP attack,IMSI information disclosure,middle attacks and other security issues.It has high security and maintains low communication and computation overhead.

    Blind Recognition Method for the Cyclic code
    YAN Yu-Han
    . 2011, 24(3):  112. 
    Abstract ( 1207 )   PDF (455KB) ( 976 )  
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    A further study is made of the blind recognition method for cyclic codes on the basis of the current research on the blind recognition method in the communication confrontation field.A method for blind recognition of the cyclic code using the calibration relationship is proposed.This method is of great significance to the blind recognition of the tunnel code.

    The Research on and Implementation of Digital Seal Based on Digital Watermark Technology
    ZHIAO Yan-Feng, QUAN Yi-Ning
    . 2011, 24(3):  115. 
    Abstract ( 1583 )   PDF (480KB) ( 1021 )  
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    In view of the security issues of electronic documents in the OA system,the integrity and authenticity of documents are analyzed,which uses the Hash function and digital signature.A new scheme is presented that the signature of documents is embedded as watermark into the image of seal.On the basis of the encrypted interface of the COM technology and Microsoft CryptoAPI,a new plan of digital seal based on digital watermark technology is presented.Research shows that this plan can be applied to traditional and electronic documents and ensure their integrity and authenticity.

    The Study of the Wireless Network Attack Classification Technology
    CHEN Juan, MA Tao
    . 2011, 24(3):  118. 
    Abstract ( 1529 )   PDF (637KB) ( 953 )  
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    This paper summarizes the classification technology of wireless network attack in existence,on the basis of which it points out its deficiencies,and discusses the gist and standard of the classification technology of wireless network attack.It finally puts forward the classification method of wireless network attack and gives its expression.

    Study of a Method for Energy Saving of Lighting
    ZHAO Lei, LI Yuan-Da
    . 2011, 24(3):  122. 
    Abstract ( 1350 )   PDF (547KB) ( 824 )  
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    Energy saving measures of lighting are studied.The traditional energy-saving measures are summed up and new energy saving means and control strategies of lighting are introduced.A new type of energy saving lighting light pipe technology is presented.

    Research on the  Internet Experiment  Teaching Method
    SUN Cui-Juan
    . 2011, 24(3):  125. 
    Abstract ( 1262 )   PDF (401KB) ( 905 )  
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    Several theoretical and experimental teaching method are put forward for internet experiment teaching.A feasible teaching method is studied on the basis of the objective and reasonable testing system to cultivate more technical engineers in the fields of network planning,engineering,maintenance and management.


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