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15 February 2011 Volume 24 Issue 2
  
    Articles
    Design and Study of a Dual Band-Notched Ultra-wideband Antenna
    WANG Wei, GONG Shu-Xi, ZHANG Fei-Fei, YAN Ying, XUE Jin-Yuan
    . 2011, 24(2):  1. 
    Abstract ( 2676 )   PDF (736KB) ( 1216 )  
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    This paper presents a simple dual band-notched circular disc monopole (CDM) ultra-wideband antenna with CPW-feed and the ground plane consists of two semiellipses,thus achieving the ultra-wideband antenna and miniaturization.By cutting two U-shaped slots on the feed line and patch,two notched bands of 650 MHz and 590 GHz are achieved.The measurement result of physical antennas show that with the standing wave ratio (VSWR) < 2 the bandwidth is 2.97 GHz to 12.75 GHz and the antenna gain is high within the frequency band with satisfactory radiation properties.A good agreement is achieved between simulated and measured antenna characteristics.

    Design of a Higher-order Audio Equilibrium Filter Based on FPGA
    TIAN Zhi-Jun, WANG Min
    . 2011, 24(2):  4. 
    Abstract ( 1862 )   PDF (656KB) ( 1034 )  
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    A 1 024-order digital equilibrium filter is designed and realized on EP1C3 series FPGA,which makes full use of the FPGA's on-chip resource by sacrificing time for space,and could also realize the equilibrium characteristics of various frequency responses and functions of the simplified digital equilibrium filter by reloading coefficients,and thus the purpose of designing the filter is attained.

    Design and Simulation of a Broadband Amplifier
    WU Li-Na
    . 2011, 24(2):  7. 
    Abstract ( 1889 )   PDF (489KB) ( 1082 )  
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    This design uses TI's highspeed amplifier OPA820ID as the first stage circuit and THS3091D as the last stage circuit.Eventually we can achieve a voltage gain of 40dB from a 50 Ω output load,pass the frequency bandwidth of 10 Hz~10 MHz,and use MSP430 MCU to show the output voltage peak to peak and RMS at 1602LCD.This design uses analog electronics and MCU signal acquisition to complete gain control and output display.The system is reasonable,simple and stable.It can be applied to course design,training and other teaching occasions.

    Linear Single Supply op Amps Analysis of Static Operating Point
    MENG Xiang-Shun
    . 2011, 24(2):  10. 
    Abstract ( 1275 )   PDF (400KB) ( 1955 )  
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    This paper studies the Input-Output transfer curve of linear Operational Amplifier under a Single-Supply condition,with focus on the static operating point of the negative feedback operational amplifier,for linear Single power supply amplifier operating point set to provide a reference.

    Design of a Kind of Sequence Code Detector
    ZHANG Fei-Long, WANG Jian-Bin, LI De-Liang
    . 2011, 24(2):  13. 
    Abstract ( 1342 )   PDF (452KB) ( 916 )  
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    Three circuits for the design of a kind of sequence code detector are introduced.The circuits are widely used in burglary insurance,cipher certification etc.In addition,they can be used in auto-intercept of sensitive words in great data identification.The circuits are designed in the way of digital electronics with high reliability and programmable procedures.

    Design and Analysis of the Microstrip Omnidirectional Antenna with a Short-circuit Matching Structure
    YAN Shu-Bao
    . 2011, 24(2):  15. 
    Abstract ( 1560 )   PDF (774KB) ( 1139 )  
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    Including the microstrip gradient structure and short-circuit matching structure,the microstrip ominidirectional antenna proposed in this paper improves antenna impedance matching,reduces the antenna's voltage standing wave ratio and increases the gain of the antenna.The physical antenna is made of a series of 7 microstrip units.In the frequency range of 2 400~2 483.5 MHz,the measured VSWR is less than 1.35,and the average gain is 9 dBi.Using more cascaded microstrip units can increase the antenna gain.The antenna is suitable for mobile communication base stations.

    A Wireless Transmission Data Modulation Technique with High Band Efficiency
    NI Bing-Wei, ZHANG Yue
    . 2011, 24(2):  19. 
    Abstract ( 1819 )   PDF (487KB) ( 998 )  
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    VWDK,a new data modulation technique with high band efficiency is introduced.Using this technique,the frequency band needed for data transmission can be greatly compacted without loss of SNR.The theory of VWDK is explained and the simulation results are also presented.The band efficiency of VWDK is estimated and the design proposal for the VWDK transmission system is indicated.

    Design and Realization of a Sinusoidal Signal Generator Based on DSP
    LIAO Bo-Lin, WANG Xing-Sheng, LIN Kun, CHEN Xu-Wei, HAN Huai-Mei
    . 2011, 24(2):  21. 
    Abstract ( 2016 )   PDF (635KB) ( 972 )  
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    This paper presents the design principle and method to produce a sinusoidal signal generator based on TMS320C5402 chip,and describes in detail the design of the hardware circuit structure and software process flowchart of the sinusoidal signal generator.On the basis of the DSP hardware features and by using a Taylor series expansion law to get the sine wave output set parameters,the design is fulfilled.Unlike the general signal generator with the fixed mode and unprogrammable waveform,this signal generator generates a real-time,high-precision waveform with good stability,and its frequency and voltage can be easily adjusted.

    Programming of Serial Communication Based on Visual C#
    Zhai Xi-Shu, WANG Bao-Xin, FAN Miao
    . 2011, 24(2):  24. 
    Abstract ( 1706 )   PDF (453KB) ( 1035 )  
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    This paper introduces the realization of serial communication by SerialPort in the Visual C# 2008 environment.It also covers the method for simple data processing.The serial communication program can be written with convenience and flexibility by SerialPort.The software interface produced is friendly and easy to operate.It is shown that good effect can be achieved by using SerialPort.

    MIMO Radar Based on the Frank Complementary Code
    FENG Jun-Jie, ZHANG Tai-Rong, LIU Song-Hong
    . 2011, 24(2):  27. 
    Abstract ( 2070 )   PDF (562KB) ( 981 )  
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    Multiple-Input Multiple-output radar uses multiple antennas to simultaneously transmit orthogonal or non-coherent waveforms and it uses multiple receiving antennas to receive and separate the reflected signals,which is equivalent to forming a huge virtual array.By optimizing the transmission waveforms  the performance of radar can be improved.Pseudo random codes are easy to construct,but it has drawbacks of high cross correlation and auto-correlation sidelobes.The Frank complementary code sequence has better correlation properties and can generate lower range sidelobes,which can be used in target imaging.

    Design of a Programmable Stimulant Radar Signal Source
    LIU Hong-Biao, JIA Lu-Qin, CUI Wei
    . 2011, 24(2):  30. 
    Abstract ( 1589 )   PDF (698KB) ( 915 )  
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    The paper designed a Stimulant Radar Signal Source that can be configured neatly by software,which make use of C8051F340 of Silicon Company control direct digital synthesizer AD9858 to output stimulant radar signals.In the paper,it elaborated on the designed electric circuit structure and the design method of the software,and verified the performance of the signal source.

    Monitoring System for Methane Concentration Based on ARM and the Rational Filter
    LIU Yu-Bin, DING Wan-Shan
    . 2011, 24(2):  33. 
    Abstract ( 1318 )   PDF (609KB) ( 961 )  
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    The system of methane concentration data collection is introduced.This system uses the detection technology based on the theory of molecular absorption of infrared radiation to design a system of CH4 concentration detection infrared sensors,which have fast response and can work under hazardous conditions.The signal conditioning circuit uses the lock-in amplifier for weak signal detection,and by using the rational filtering algorithm to process the data in software design,it can significantly improve the accuracy and stability of detection.Experimental results show that the testing precision is 5 ppm.It can be widely used in dangerous gas monitoring in such sectors as chemistry,electric power and mining.

    Research on and Electric Design of the Ultrahigh-pressure System
    YANG Zu-Chun, CHEN Jian-Bin
    . 2011, 24(2):  37. 
    Abstract ( 1697 )   PDF (667KB) ( 904 )  
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    This paper discusses the working process of the intensifier,and then sets up the mathematical model of the ultrahigh-pressure system.It also analyzes the major contributing factor to the pressure fluctuation of the system through simulations.The electrical circuit and control circuit for the ultrahigh-pressure system are designed.

    Automatic Realization of the Decoupling Network Based on the Capacitor Constants PDS
    Jin Ya-Dong, WANG Lin-Lin, LI Xiao-Xia
    . 2011, 24(2):  40. 
    Abstract ( 1675 )   PDF (681KB) ( 907 )  
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    This article analyzes the decoupling network of the power distribution system from the aspect of energy transfer in the time domain,and describes the distribution scheme for the decoupling network based on the constants of the decoupling capacitor.In addition,it achieves the automatic allocation of the decoupling capacitor network in each part of the power distribution system based on VC.And the time-frequency domain simulation is made by calling the software of Hspice.The result shows that the method can effectively decouple the power distribution system.

    Design of a Cow Activity Data Acquisition System Based on ZigBee Technology
    ZHAO Du-Jun, BAO Hong, LIAO Zhi-Jian, XU Zhi-Kang
    . 2011, 24(2):  44. 
    Abstract ( 1708 )   PDF (639KB) ( 958 )  
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    This paper describes the principle for and implementation of a cow activity data collection system.This system has radio frequency chip CC2430 as the core and uses ZigBee wireless sensor network technology to form a wireless network in the dairy farm.It periodically collects the activity data of the cows through the wireless network,and then analyzes and processes the received data to determine whether the cows are in heat.The system has good application and economic prospects.

    IEEE 1394b Bi-directional Data Transfer System Based on NIOSII
    YANG Li-Xiang, LI Yu-Shan
    . 2011, 24(2):  47. 
    Abstract ( 1093 )   PDF (665KB) ( 892 )  
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    This paper designed a 1394b bi-directional data transfer system by using the embedded processor NIOSII.It simply introduced the hardware structure of the system and described the working process of the software in detail.The emphasis is putted on the implement procedure of asynchronous transfer and isochronous transfer.After testing,we found that the system has advantages of high speed,good reliability and real-time performance,and has upper applied value in practice.

    A UART IP Core For Wishbone Bus Interface
    WANG Zhen-Hua, HE Ming-Hua
    . 2011, 24(2):  50. 
    Abstract ( 1477 )   PDF (657KB) ( 922 )  
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    This paper introduces a UART IP core for Wishbone bus interface.The design uses a top-down modular division and the combination of finite state machine approach,because of its application of the standard Wishbone bus interface,so that computer systems and communications between serial devices more flexible and convenient.Test results show that this new architecture is feasible and effective.

    Application of the CAN Bus to the Communication Between Microcontrollers
    YU Miao
    . 2011, 24(2):  54. 
    Abstract ( 2601 )   PDF (456KB) ( 1245 )  
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    This paper describes the design of more microcontrollers connected with the CAN bus.These microcontrollers,communicated with the CAN bus on a PCI9810-CAN adaptor,consist of an area network.Therefore,the PC can control and communicate with every microcontroller,and each microcontroller can communicate with any other freely.

    Design and Realization of a 64bit High-speed PCI Bus Interface
    LI Guo-Guang, LUO Feng
    . 2011, 24(2):  57. 
    Abstract ( 1590 )   PDF (494KB) ( 875 )  
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    This paper presents a kind of high-speed PCI bus interface based on PCI9656,and the main method of transferring data is DMA transmission.This paper introduces the internal functions and structures,and discusses the process of WDM driver developing,and analysis the configuration sequence in DMA transmission at the local bus.At last,it gives some details needed to notice in design.Application results shows that this kind of bus interface works stably and efficiently,and it can be used in the system of high-speed data transmitting.

    Design of the Blood-oxygen Monitor Core Hardware Circuit and Multisim Simulation
    YANG Dong-Ming, WAN Pin, ZHANG Bo-Wei, LIAO Li-Min
    . 2011, 24(2):  60. 
    Abstract ( 1944 )   PDF (840KB) ( 1643 )  
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    For real-time detection of oxygen saturation for timely treatment of the brain or heart,which are very sensitive to oxygen inadequacy,the near-infrared wavelengths double photoelectric pulse oximeter transmission method is adopted.The illuminant is controlled with the H bridge circuit and the filter circuit is built with general op-amps.Parameters by theoretical calculation is compared with the computer simulation results in Multisim and satisfactory results are obtained.It is shown that the design of the circuit parameters is feasible and can be a help in making the phy
    sical blood-oxygen monitor.

    Digitalized Design of the Control Circuit for the Gasoline Generator Set
    YAN Yong-Ping, WANG Ling
    . 2011, 24(2):  63. 
    Abstract ( 1301 )   PDF (470KB) ( 985 )  
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    This paper analyzes the control and protection circuit of a gasoline generator set and proposes a digital circuit and MCU to improve the design.Experimental results show that this design realizes the control and protection of the generator set,optimizes the design and meets the technological requirement.

    Study of the Electromagnetic Compatibility Trial and Flight Test of Aircraft
    YANG Jian, ZHANG Peng
    . 2011, 24(2):  66. 
    Abstract ( 1438 )   PDF (646KB) ( 927 )  
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    The electromagnetic interference source and common protection of aircraft are analyzed.The classification and goal of the EMC ground-based test of aircraft are introduced.Related knowledge to the EMC flight test of aircraft is discussed.The role of the EMC flight test engineer is described.

    Study of Energy Distribution Using Surface Electromagnetic Waves
    LI Yong-Feng, ZHOU Hang, WU Xiang
    . 2011, 24(2):  70. 
    Abstract ( 1227 )   PDF (600KB) ( 862 )  
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    The surface electromagnetic wave at the 2D interface is studied.The expressions of the electromagnetic field and energy flux density for the TE surface wave are derived.The necessary existence condition for surface waves is derived.The interfaces are divided into left-hand interface and right-hand interface.The propagation of surface electromagnetic waves at the 2D interface is simulated.Finally,the distribution of energy by using surface electromagnetic waves is discussed and simulation results are obtained.

    Jitter Analysis and Separation of Random Data Based on Simplified Measurement
    WANG Lin-Lin, JIN Ya-Dong
    . 2011, 24(2):  73. 
    Abstract ( 1668 )   PDF (613KB) ( 896 )  
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    In the communication system,we often use the eye diagram of a digital oscilloscope to analyze the jitter of random data,which has a relatively high expectation of hardware that it should be able to make real-time measurements.Based on the analysis of the type of jitter and its cause,this article presents a new scheme for separating jitter based on simplified measurement.That is,we can obtain most of the components of jitter merely by measuring the time interval of “rising edge-falling edge-rising edge” randomly,which lowers the requirement on the hardware circuit.

    A New Algorithm of Calibrating 3-CCD Scanners Based on 3D_Lut
    LUO Bin, YUAN Sheng-Chun
    . 2011, 24(2):  76. 
    Abstract ( 1705 )   PDF (481KB) ( 945 )  
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    A new scanner calibration algorithm on the basis of 3D_Lut is presented,by which high-accuracy color calibration of equipments is achieved according to the arbitrary and irregular color sample patches of scanners.To solve the problem of operation complexity due to the large quantity of samples,a new method of adaptive tabulation and interpolation is proposed.This algorithm has the advantages over the traditional algorithm of scanner calibration of high accuracy and good real-timeness and that it can be used for color calibration of various equipments.

    Improvement of ECDSA Algorithm Based on Koblitz Curve
    YIN Can, LU Chen
    . 2011, 24(2):  79. 
    Abstract ( 1465 )   PDF (497KB) ( 909 )  
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    The capability of ECC depends on the efficiency of scalar multiplication.Furthermore,fast scalar multiplication algorithm on Koblitz curve is the top demanding task in the research of scalar multiplication.In Lee et al.algorithm,Frobenius map is utilized to expand integer k and each coefficient of the expansion is represented as a binary string.In this paper,with the application of Joint Sparse Form to the coefficients,the efficiency of algorithm is improved at a lower storage requirement.The improved algorithm was applied to promote ECDSA algorithm could accelerate the process of verifying signature and decrease the time of verifying signature.

    Realization of a Rapid Detection System for Connectivity in Ethernet
    PEI Guang-Chao, YE Bing
    . 2011, 24(2):  83. 
    Abstract ( 1532 )   PDF (774KB) ( 887 )  
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    To accomplish a millisecond transmission and receiving package,the system deals with the Continuity Check Message of “IEEE 802.1ag” protocol based on the auxiliary CPU,which realizes the function of rapid detection for connectivity in Ethernet.With two equipments simulating a small network,the system can check the connectivity in Ethernet.

    Jitter Separation Based on the Tail-Fit Algorithm
    FAN Yuan-Hao
    . 2011, 24(2):  86. 
    Abstract ( 1403 )   PDF (628KB) ( 836 )  
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    This paper introduces the definition and classification of jitter,puts forward a technique of  jitter separation based on the Tail-Fit algorithm,offers the fitting result,and testifies the efficiency of the algorithm.

    Design and Implementation of a Huffman Coding and Decoding System
    ZHANG Xiao-Hong
    . 2011, 24(2):  90. 
    Abstract ( 1395 )   PDF (639KB) ( 871 )  
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    It is important to compress data in the rapid transmission and storage of information.This paper introduces the design and implementation of a Huffman coding and decoding system based on the definition of the Huffman tree and Huffman algorithm,which is beneficial to a good understanding of the data structure and program design.

    Object-oriented Modeling of the Automatic Test System Software Based on UML
    TAO Nai-Li, LIU Wen-Bo
    . 2011, 24(2):  92. 
    Abstract ( 1270 )   PDF (992KB) ( 883 )  
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    This passage analyzes the present situation of the automatic test system,figures out the idea of object-oriented modeling of the automatic test system using UML tool,and exemplifies the process of object-oriented modeling of the avionics simulator system software.The avionics simulator system software has been represented from the aspects of function,static model and dynamic model using use case,class diagram and sequence diagram of the UML language.

    Design of a Computer Room Monitoring System Based on the Modbus Protocol
    LIU Jia-Xiao, XIE Yun
    . 2011, 24(2):  95. 
    Abstract ( 1773 )   PDF (552KB) ( 896 )  
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    Based on the ARM embedded processor,this paper introduces a computer room environment monitoring system using the WinCE6.0 embedded operating system.The data collection module communicates with the ARM embedded processors by the Modbus protocol.After the pretreatment,the collected data are sent to the remote control platform via Ethernet and thus the remote monitoring of the computer room environment is implemented.

    Secondary Development of Cadence Based on VC
    MA Liang
    . 2011, 24(2):  98. 
    Abstract ( 1380 )   PDF (584KB) ( 1003 )  
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    The secondary development of Cadence can accomplish new customized functions and enhance operability.It can also perform time-consuming and repetitive work for engineers and thus save labor and time.This paper discusses the secondary development of Cadence in visual C++,generates a VC operating interface,controls Cadence by using the communication between visual C++ and SKILL language,and completes some specific operations.Finally,all the codes are given.

    A New Method for Reverse Color Judgment for the Binary License Plate
    DU Bing-Xin, CUI Ju
    . 2011, 24(2):  102. 
    Abstract ( 1800 )   PDF (648KB) ( 3791 )  
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    The paper presents a new method for judging whether the color of a binary license plate needs to be reversed.The reverse color judgment is made by calculating the proportion of white pixels between 2 and 6 characters areas of a license plate as well as the white pixel ratio of vertical projection.Experiments show that this method has high accuracy.

    Multi-class Classification Program for the Secret Algorithm of the JPEG Images
    YAN Peng-Chao
    . 2011, 24(2):  105. 
    Abstract ( 1224 )   PDF (687KB) ( 835 )  
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    A multi-class classification program for the secret algorithm of the JPEG images is proposed.First,a quantitative analysis is made of the possibility of multi-class classification,then some compression classification methods are introduced,and a multi-class classification algorithm is designed,and finally experimental results are analyzed in detail.On the basis of re-encryption and by using the classification method of compression proposed by Fridrich J.this design realizes the multi-class classification of a hidden image with high accuracy and efficiency.

    Identification and Synthesis of the Simulation Image with Rotation
    CHEN Zu-Hong, ZHANG Pei-Kun, LIU Jia-Ying, LI Jing
    . 2011, 24(2):  109. 
    Abstract ( 1508 )   PDF (682KB) ( 808 )  
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    Two methods for identifying the revolving image on the computer are put forward: the matched transform correlator and the joint transform correlator.Comparison of the analog data of the two algorithms shows that the joint transform correlator algorithm is better in recognizing the target object.And simulation experiments show that computer simulation recognition is superior to the real optical pattern recognition in succinctness and significance.

    Analysis of Coal Mine Gas Optical Fiber Sensing Gas Based on Spectrum Absorption
    ZHANG Chun-Zhi
    . 2011, 24(2):  113. 
    Abstract ( 1119 )   PDF (547KB) ( 907 )  
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    The basic principles of gas absorption is analyzed.An optical fiber sensing gas system is studied,which has been used in a super test of mine with good results achieved.It is proposed that the coal mine gas optical fiber sensor based on spectrum absorption can be used both for large-scale monitoring of coal mine gas and for continuous online monitoring of underground gas and therefore has broad application prospects.

    Study on Fe-based Electro-Galvanized Layer of Chromium-Free Passivation
    YUN Guang-Ping, GUO Wan-Zhen
    . 2011, 24(2):  115. 
    Abstract ( 950 )   PDF (588KB) ( 1007 )  
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    In this paper,to replace the traditional highly toxic chromate passivation,I researched the chromium-free passivation technology of the galvanized sheet,and choosed molybdate as the main component to study the galvanized steel passivation technology systematically.I discussed the temperature of passivation,the time of passivation,the pH value of passivation to study the impact of the passive film and corrosion resistance.The corrosion resistance of samples with Chromium-free passivation was studied using tests of lead acetate,electrochemical testing.Experimental results show that the chromium-free passive film has a good corrosion resistance,but there is still a certain gap with the chromate.

    Design of Alarm Agent for Network Fault Management
    ZHANG Ying
    . 2011, 24(2):  119. 
    Abstract ( 1186 )   PDF (492KB) ( 890 )  
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    This paper introduces an alarm agent module for TMN fault management.The major function of fault management is realized on the basis of the common and specific features of various network management  devices.The design can also serve as a platform.Its operation shows that the system has great utility and extendibility.

    Teaching Reform for Computer Network
    YANG Bai-Long, GUO Wen-Pu, WUI Su-Yuan, WANG Qun-Ce
    . 2011, 24(2):  122. 
    Abstract ( 1714 )   PDF (365KB) ( 963 )  
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    This paper proposes the guiding ideology and measures on the course construction of Computer Network,offers a comprehensive design and innovative reform of course contents,teaching methods,teaching resource,course experiment and examination.The work has brought good effect on course construction and is valuable for reference and demonstration.

    Application of Multisim in the Teaching of Electrical Technology
    LI Ruo-Qiong
    . 2011, 24(2):  124. 
    Abstract ( 1327 )   PDF (680KB) ( 898 )  
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    In view of the present status and problems in the teaching of Electrical Technology for non-electronic majors,the Multisim simulation experiment is done in class,enabling theoretical class teaching to be integrated with practical simulation technology.And good teaching effect is achieved.

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