Volume 26,Issue 5,2003 Table of Contents

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  • 1  Adjustive Mechanism Design Based on Planar Constraint Uncertainty
    LI Tai fu HUANG Mao lin ZHAO Jie
    2003, 26(5):1. DOI: 10.11835/j.issn.1000-582X.2003.05.001
    [Abstract](770) [HTML](0) [PDF 493.65 K](120)
    Abstract:
    For normal planar closed chain mechanism, it is based on ideal planar constraint condition. The authors took crank leader mechanism as an example, and analyzed influences resulted from uncertain factors, such as manufacturing error. The result shows it belongs to statically indetermination mechanism. After analyzing its over-constraint and eliminating it, in this way, it become statically determination mechanism and can be assembled without obstacle. However, in the process of practical running, the mechanism can give birth to new kinematic constraint, frictional constraint and dynamic constraint etc., so over constraint emerges again. Therefore, it is necessary to analyse its adaptability in total running process. The conclusion shows that design of adaptability mechanism normally eliminate geometry over constraint at first, then it is analyzed that whether there is new over constraints from all kind of external constraints in the process of running.
    2  Experiment Modal Analysis System Based On GraphicCell Object
    YANG Chang qi ZHANG Yue jun QIN Shu ren
    2003, 26(5):6-9. DOI: 10.11835/j.issn.1000-582X.2003.05.002
    [Abstract](690) [HTML](0) [PDF 376.52 K](127)
    Abstract:
    A structure input and output method of graphic cells object oriented is proposed, and input and output model based on OpenGL graphic industry standard is founded. Using the technologies of MFC and OpenGL, the input, display and dynamic output of 3D graphics are realized, which are based on graphic cells such as node, beam, triangle, quadrangle element. Graphic cells keep consistency well with the elements of finite element in the aspects of geometry, reading and writing of structure files and so on. Using the model, the functions of structure input, data gathering and analyzing, and modal vibrating shapes output etc are finished. A visual experiment modal analysis system is daeloped.
    3  Uncertainty Analysisof Financial Evaluation of Investment Project and Its Application
    YI Shu ping REN Qiang ZENG Li ping
    2003, 26(5):10-13. DOI: 10.11835/j.issn.1000-582X.2003.05.003
    [Abstract](776) [HTML](0) [PDF 295.06 K](243)
    Abstract:
    The economy index used in investment project is usually influenced by many uncertain factors because the basic data of which comes from forecast and budget. This paper studies such common uncertain analysis method as balance analysis of profit and loss, sensitivity analysis. The problems in these methods are pointed out and a new method of uncertainty analysis based on the Analytic Hierarchy Process and Monte Carlo method is advanced, along with its compute method in economy analysis of investment project. To an investment project, the authors set the NPV as the goal, set investment amount, prosecution cost and product price as the simulant values, which have relatively great effect on NPV. By using the new method in uncertain analysis, the conclusion can be drawn that the project is greatly influenced by the uncertain factors of future and it has high risk. A case study demonstrates that the new method can synthetically analyze the financial variety caused by uncertain factors.
    4  EDM Lettering Technology of Large-scale Workpiece'''' s Surface
    XIE Zhi jiang XIAO Yi HAN Zhi hua
    2003, 26(5):14-17. DOI: 10.11835/j.issn.1000-582X.2003.05.004
    [Abstract](923) [HTML](0) [PDF 373.44 K](177)
    Abstract:
    The actuality of lettering technology on workpiece's surface is introduced from domestic and abroad ,and the principle of using EDM to carve characters on large-scale workpiece's surface are analysed at economical and technologic point of view. The technologic scheme is put forward according to the principle of EDM and the character of EDM lettering on large scale workpiece's surface,which is based on headstock and electrical source control tank of minitype EDM tool. The key technologies, the whole makeup,the motion between electrode and workpiece at three coordinates, precise orientation of electrode and cycle system of work liquid are emphatically studied. Finally,an special EDM lettering tool of lager scale roller for a large scale iron & steel enterprise is briefly described. The application indicates that the technologic scheme is economical and useful,and the EDM lettering tool is stable and reliable.
    5  Experimental Research on Noise Reduction of Mini-car
    DENG Zhao xiang ZHANG Zheng liang YANG Cheng
    2003, 26(5):18-21. DOI: 10.11835/j.issn.1000-582X.2003.05.005
    [Abstract](805) [HTML](0) [PDF 376.63 K](140)
    Abstract:
    By means of noise sources separation experiment of mini car and the surface acoustic intensity measurement of the engine, this paper finds that the main noise source of the mini car is the intake noise. According to the frequency spectrum analysis of the intake noise, the design frequency of the three cavity Helmholz intake silencer is determined. The results of the experiments show that the silencer, which is patented, has a remarkable effect, about 8 dB(A) decrement, on the noise reduction of the mini car.
    6  Brake 3D Models Parameterized Design
    ZHANG Jing shuang DENG Zhao xiang YANG Shan chen
    2003, 26(5):22-25. DOI: 10.11835/j.issn.1000-582X.2003.05.006
    [Abstract](691) [HTML](0) [PDF 392.16 K](202)
    Abstract:
    Aiming toovercome thelimitation of the traditional design methods of automobile parts, this paper presents a design and analysis method based on "Soft Prototype". By developing a professional CAD system Drum Brake Design and Analysis System, the authors researched the design method of "Virtual Products" and the technologies of parameterized modeling. During the development of software, some new methods are presented. In this CAD system, the database, graphical browser and designing module are united perfectly, and parameters are utilized to create models. Such a system can greatly improve design efficiency and reduce the time of new products development
    7  Development of Automobile Noise and Vibration Analysing System with Object Otiented Technology
    MIN Zhao yuan DENG Zhao xiang YANG Cheng LIN Wei WANG Xiao hu
    2003, 26(5):26-29. DOI: 10.11835/j.issn.1000-582X.2003.05.007
    [Abstract](679) [HTML](0) [PDF 340.51 K](100)
    Abstract:
    With the developing of the automobile industry, how to control the noise and vibration level of the products come to urgently for the auto factories during their developing and producing period. Finding out the main noise source and vibration source quickly, analyzing the noise and vibration signal effectively, contriving a noise descending algorithm reasonable and economical become the first and most important job for auto corporations. At the mean time it complicate the developing guide line of the noise and vibration testing system. With object oriented technology, we can develop the noise and vibration testing system in a short time and with a low cost. The object oriented technology emphasizes the circulation, exoteric and expandable of the codes. It enables us developing the system follow a flexible, integrable and economical procedure..
    8  Three Phase Harmonic Power Flow Using PhaseComponent for Asymmetric Network
    TANG Yun long LUO Jian YAN Wei LIU Fang WANG Guan jie
    2003, 26(5):30. DOI: 10.11835/j.issn.1000-582X.2003.05.008
    [Abstract](653) [HTML](0) [PDF 284.56 K](1164)
    Abstract:
    With the increasement of the harmonic quantity in power system ,single phase harmonic power flow calculation can't meet the needs. This paper discusses the components model in detail under harmonic condition in three phase distribution power system, include generator,transformer,line and load. Particularly, the transformer model considers the winding connection, the phase shifting among primary and secondary windings, and the off-normal tapping.The three-phase model of transformer, used in traditional harmonic power flow, may the preuent the model from converging, so the paper proposes a three phase back forward sweep harmonic load flow algorithm based on phase-components. At last, a test example was used to prove the algorithm. The results indicate that the proposed method is efficient.
    9  Effect of Mischmetal Additions on the Ignition Temperature ofMolten ZM5 Magnesium Alloy
    ZOU Yong liang LI Hua ji XUE Han song RAO Jing song
    2003, 26(5):33-36. DOI: 10.11835/j.issn.1000-582X.2003.05.009
    [Abstract](813) [HTML](0) [PDF 364.03 K](990)
    Abstract:
    Magnesium alloy is prone to burning during its melting and casting in air, which is a major factor in obstructing its application. Fluxes and cover gases are currently used for the melting and production processes, and semi solid thixocasting is also used to lower the operation temperature, but there still remain many problems. Alloying is a promising method of preventing Mg from burning. The effect of mischmetal additions on the ignition temperature of ZM5 Mg alloy was investigated and compared with that of pure rare earths. It is shown that an addition of 0.12 % mischmetal can greatly heighten the ignition point and such an alloy can be widely applied.
    10  Experiment Analysis on Medical-Solid-Waste Layer Resistance in CFBC
    HUANG Tao ZHANG Li RAN Jing yu PU Ge PENG Xiao dong
    2003, 26(5):37-39. DOI: 10.11835/j.issn.1000-582X.2003.05.010
    [Abstract](630) [HTML](0) [PDF 313.09 K](1188)
    Abstract:
    The relationship between layer resistance and primary air was analyzed from the experiment of CFBC Medical Solid Waste layer resistance,and the influence of layer ply & diameter of Medical Solid Waste on layer resistance and minimum fluidize air flow flux were analyzed too. Compared with normal coal layer,it has less primary air flow flux. and the Layer resistance is less too .
    11  Cold Model Experimental Study Using Reburning Tecnology to Reduce the emissions of NOx
    LU Xiao feng ZHENG Xian Guo LIU Han zhou ZHAN Yue hang
    2003, 26(5):40-45. DOI: 10.11835/j.issn.1000-582X.2003.05.011
    [Abstract](634) [HTML](0) [PDF 569.86 K](936)
    Abstract:
    A cold model (its ratio is 1:12.5) of a 50 MW tangentially pulverized coal-fired boiler was built and the mixture characteristic between a simulating gas (hot air) and a main airflow (cold air) were gotten at different ejecting methods and quantities of the simulating gas through measuring the temperature pattern distributing in the furnace of the model. The simulating gas spouted from front and rear walls resulted a more even mixture characteristic, and the tangentially ejected simulating gas is more suitable for the tangentially pulverized coal-fired boiler, and the tangentially ejected OFA is also of advantage to it. The effect of quantities and locations of the simulating gas on the mixture characteristic was also discussed.
    12  Experimental Investigation of Passive Emergency Core Cooling System
    PENG Yun kang LI Kui ning TONG Ming wei ZHENG Hua XIAO Ze jun
    2003, 26(5):46-51. DOI: 10.11835/j.issn.1000-582X.2003.05.012
    [Abstract](686) [HTML](0) [PDF 376.32 K](1071)
    Abstract:
    The effect of different break size at cold leg , different pressure balance line and automatic depressurize system on transient behavior of passive emergency core cooling system was investigated on the AC600CMT test facility. The experiment process and experiment results were described.
    13  Phase Behavior of W/O Microemulsion
    HE Cong lin WANG Bo chu
    2003, 26(5):52. DOI: 10.11835/j.issn.1000-582X.2003.05.013
    [Abstract](1002) [HTML](0) [PDF 302.29 K](1569)
    Abstract:
    The phase behavior of W/O microemulsion employed blend NPE4.2 and NPE10 as surfactants was studied. The influence of blend surfactant proportion, surfactant dose co-surfactant dose, various cations and temperature on W/O microemulsion phase behavior was examined by way of electric conductivity with the maximum dissolve water (solution) being the target. Experiments indicated that as the NPE 4.2 :NPE 10 is about 1.2:1 and (S+A):O is about 3:7, the maximum dissolve water was acquired. When the water was substituted by other cations solution or the temperature was increased, the effect to the microemulsion was resemble to the water. But the domain of W/O microemulsion is decreased.
    14  AuthorizedAdministration of Electronic Documents in Enterprises
    WANG Cheng liang ZENG De
    2003, 26(5):55-58. DOI: 10.11835/j.issn.1000-582X.2003.05.014
    [Abstract](344) [HTML](0) [PDF 328.66 K](945)
    Abstract:
    When prominence of security problems increasing,it is of importance to savethe sensitive electronic documents into database. The user-role mechanism is employed in the process of managing documents. However, it can't provide the flexibility of authorized access because of the dynamic generating particularity of the electronic documents which need maintaining continually. A tree model of entity authorization is introduced based on discretionary access control mechanism. The approach can grealty simplify the authorization, increase the flexibility and is more accordant with the practical requirement of enterprises.
    15  Status Quo and Expectation of Human-machine Interaction in HCR
    LI Gang HUANG Xi yue YUAN Rong di HUANG Tong yuan
    2003, 26(5):59-63. DOI: 10.11835/j.issn.1000-582X.2003.05.015
    [Abstract](947) [HTML](0) [PDF 461.90 K](1597)
    Abstract:
    Human-centered idea and human-machine collaboration are emphasized in the Human Centered Robotics, which is mainly used for human-machine cooperation required mission in dynamic and non-structural environment. This paper presents a WearComp based interface that gets over the space and time limitation on human-robot interaction. By adapting AR(augment reality) in outputting channel, the information of robotics status and warning was accentuated in the transmission. That method effectively saves the resources of transmission band and reappearance, lightens the burden of operators and contributes to a good operator consciousness to local condition and remote environment. By parallel and mutual compensation of MultiModality interaction, and by integrating and fusing the redundant information, the ambiguity and noise of inputting information can be eliminated. All of above get rid of input bottleneck; a more efficient and humanistic human machine interaction is provided.
    16  Embedded Image Coding on Wavelet Coefficients
    LIU Guo jin YANG Xiao fan DONG Shi du HUANG Xiang sheng
    2003, 26(5):64. DOI: 10.11835/j.issn.1000-582X.2003.05.016
    [Abstract](577) [HTML](0) [PDF 431.31 K](1109)
    Abstract:
    The modeling of wavelet coefficient for still image compression is studied.Firstly,through simulation experiments on three classical wavelet coefficient models(i.e.,EZW model,SPIHT model/and EBCOT model),it is shown that SPIHT is superior to EZW in terms of compression performance(0.6 dB higher)and the compression performance of EBCOT is significantly better than that of SPIHT on average. Then the cause for such performance differences is explained through the analysis of models.Finally a new wavelet coefficients model is proposed which combines the advantages of the three classical models.Experimental results show that our model is better than the above mentioned three models with respect to compression ratio.
    17  Roheogical Effect for Magneteroheological Fluids
    SI Hu PENG Xiang he
    2003, 26(5):72-75. DOI: 10.11835/j.issn.1000-582X.2003.05.018
    [Abstract](1339) [HTML](0) [PDF 280.02 K](293)
    Abstract:
    Magneteroheogical Fluids have very wide application due to the particular magneteroheogical effect. It is the key to develop ment of magneteroheological fluids and application to research on the magneteroheological effect. This paper discusses the magnetorheological effect for Magnetorheological (MR) fluids from the view of theory and experiment. It describes the influence of the applied magnetic field, volume fraction of the particles and the size of the magnetic particles on the rheological effect of MR fluids. It is shown that the experiment result agrees with the theoretic one. That provide the basis for the engineering development and the engineering applications.
    18  Effective Electromechanical Coupling Property of Multiphase Dielectrics
    JIANG Ye jian ZHANG Pei yuan
    2003, 26(5):76. DOI: 10.11835/j.issn.1000-582X.2003.05.019
    [Abstract](588) [HTML](0) [PDF 344.45 K](114)
    Abstract:
    A new way of defining the effective physical quantities by other apparent physical quantities is proposed. Accordingly, a new framework is induced to construct the effective electromechanical coupling constitutive equation of multiphase dielectric materials .In this framework, a special mode is studied. The effective constitutive equation of transversely isotropic multi-layer multiphase dielectrics is set up, and the expression of effective electromechanical coupling constitutive equation of transversely isotropic multi-layer multiphase in plane-stress is given.
    19  Architecture of Networked Manufacturing Based on Supply Chain
    ZHANG Cai fang DAN Bin ZHANG Xu mei
    2003, 26(5):80-85. DOI: 10.11835/j.issn.1000-582X.2003.05.020
    [Abstract](629) [HTML](0) [PDF 544.21 K](118)
    Abstract:
    The combinationof networked manufacturing and supply chain can integrate the design resource, intelligenceresource and manufacturing resource more efficaciously. Based on the compareand analysisof characteristics of the networked manufacturing and supply chain, the mode of networked manufacturing based on supply chain is brought forward, it combines and integrates supply chain and networked manufacturing to attain the effects of the complementarityof the dominanceof each other, and makes the reality of networked manufacturing more convenience, shortcutand efficiency. Based on the solution, the architecture and an operation mode of networked manufacturing based on supply chain are put forward. Finally, the applicationof networked manufacturing based on supply chain to ceramics industry is studied. Through the implementof the networked manufacturing which is based on the Supply chain dynamic allianceof ceramics industry, the process of from gaining demand information to putting products in the market is finished.
    20  Option-pricing of Completeness Market and the Choice of Hedging-trade Strategies
    FU Qiang PU Xing cheng
    2003, 26(5):86-89. DOI: 10.11835/j.issn.1000-582X.2003.05.021
    [Abstract](917) [HTML](0) [PDF 234.45 K](128)
    Abstract:
    This article is based on the existence of an arbitrage about a portfolio in an disequilbrium market under the supposition of the stochastic market. The authors defined the T option priee equilibrium price, and illuminated these definitions at first. With the knowledge of stochastic analysis, it is demonstrated that the price of European put option equals its callo ption. They both equal equilibrium price. In addition, under the same supposition, it is discussed that the choice of hedging trade planning, got the formula of hedging trading.A example to show how to use the formula.
    21  Dynamic Stabilization of Non-equity Strategic Alliance
    ZHANG Wei guo CHEN Yu
    2003, 26(5):90-93. DOI: 10.11835/j.issn.1000-582X.2003.05.022
    [Abstract](417) [HTML](0) [PDF 389.41 K](167)
    Abstract:
    Non equity Strategic Alliance is one of the middle organization forms between enterprises and the market. It is loosely coupled and agile based on the restriction and coordination by contract. Relative to Equity Strategic Alliance, it shows the agile character. But, this character causes the instability and complexity. The authors did a research of dynamic stabilization in Non-equity Strategic Alliance supported by the theories of institution equilibrium from New Institutional Economics. Presuming a control management institute M, the dynamic stabilization model of Non-equity Strategic Alliance under conditions of complete information and incomplete information is established. The author hopes to help Chinese enterprises establish Non equity Strategic Alliance was established under the changing environment.
    22  Analysis on the Disposal of the Industrial Solid Waste in the Three Gorges Region
    CUI Zhi qiang WANG Li ao HUANG Ben sheng YUAN Hui
    2003, 26(5):94-98. DOI: 10.11835/j.issn.1000-582X.2003.05.023
    [Abstract](615) [HTML](0) [PDF 416.30 K](147)
    Abstract:
    The second step of water storage for Three Gorges Reservoir will be executed in Jue,2003. Because there is still a large quantity of industrial solid waste(ISW) dumped on the reservoir bottom where should be cleaned before water storage and wastes should be disposed. After a full investigation and analyze, the total amount of ISW in the Chongqing reservoir area is about 1.66 million tons. According the principles of safe, economical and reliable, this paper describes the ISW's treatment. The ordinary ISW which is harmless and non toxic after identification should be treated on-site, the ISW that exceeds the national standards should be removed and be disposed in the landfill, and the hazardous waste should be removed for disposition or storage.
    23  Theoretically Investigation of Dynamic Characteristics of Spherical Bubble Collapse in Pulsed Abrasive Water Jet
    LU Yi yu LI Xiao hong YANG Lin
    2003, 26(5):99-102117. DOI: 10.11835/j.issn.1000-582X.2003.05.024
    [Abstract](654) [HTML](0) [PDF 334.60 K](163)
    Abstract:
    This paper theoretically investigates the characteristics of cavitating bubbles in the pulsed abrasive water jet(PAWJ) and establishes the dynamic equations of cavitating bubbles. The effects of abrasive diameter and density on the spherical bubble collapse are also analyzed. It is found that the change of abrasive diameter rarely affects the bubble collapse when the abrasive diameter and density are small whereas the smaller abrasive greatly blocks the bubble collapse when the abrasive diameter and density are comparably big. It is also shown that when the abrasive density is increased, the fluid viscosity rises, and the kinetic energy of the abrasives near the collapsed bubble is enhanced and meanwhile the intensity of cavitating erosion is weakened.
    24  A Direct Limiting Deformation Equilibrium Method for Wedge Sliding
    ZHU Fan ZHANG Yong xin ZHANG Bo JIANG Guang rong
    2003, 26(5):103-105. DOI: 10.11835/j.issn.1000-582X.2003.05.025
    [Abstract](691) [HTML](0) [PDF 214.06 K](137)
    Abstract:
    A simple and direct limiting deformation equilibrium method for wedge sliding considering all the three deformation components of the discontinuity planes is presented. The traditional limiting equilibrium method is based on a statistic system assuming that sliding is resisted only by the sliding resistance parallel to the sliding direction along the line of intersection of the two discontinuity planes. Therefore, we work out the psudo-elastic system to take care of the deformation of the discontinuities and to solve the indeterminate system. Through analysis and experiment, it is illustrated that the result based on traditional method is unsafe. The calculated results are fairly consistent with the experimental ones, while those based on the traditional method are unsafe. The stiffness of the discontinuities should be emphasized.
    25  Creep Damage Failure of Rock Salt
    QIU Xian de JIANG Yong dong YAN Zong ling ZHUANG Qian cheng
    2003, 26(5):106-109. DOI: 10.11835/j.issn.1000-582X.2003.05.026
    [Abstract](627) [HTML](0) [PDF 350.58 K](147)
    Abstract:
    Creep damage is one of the main failure types of rocksalt, so the creep experiment of Changshan and Qiaohou rocksalt is carried out. The relation between strain and time is built up combined with rheology model through observation of the generation, expand of crack in rocksalt sample. And the failure essence of rocksalt called dislocation failure, is analyzed in microscope.
    26  Option of the Firewall Location in Virtual Private Network(VPN)
    YANG Jin SUN Xiao nan
    2003, 26(5):110-114. DOI: 10.11835/j.issn.1000-582X.2003.05.027
    [Abstract](975) [HTML](0) [PDF 414.93 K](135)
    Abstract:
    Firewall is a kind of basic safe facility in Virtual Private Network. In any VPN scheme, the location of firewall must be considered conscientious.According to firewall's location, different network has different safe characteristic. Firewall should be put in front of or behind safe gateway ( VNP server), which is the focus of the argument. To share the enterprise's partial resources for outside world, firewall is different in department network. To let non-VPN user visit intranet, firewall is put behind VPN server.This paper discuss the firewall's location in fictitious special net.
    27  Method of Sun Automatic Tracking for Acceletated Outdoor Weathering Experiment Equipment
    LIN Xiao gang GAO Chao GUO Yong cai SHENTU Nan ying
    2003, 26(5):115-117. DOI: 10.11835/j.issn.1000-582X.2003.05.028
    [Abstract](482) [HTML](0) [PDF 256.08 K](873)
    Abstract:
    Outdoor Acceletated Weathering Equipment is the most widely used outdoor acceletated weathering test method in the world today. The success in development of this equipment will have a far-reaching and promoted effect on R&D of new material and new dope. Automatic and all-weather tracing solar is the tackle key problem. A new method of tracking the sun is presented, and the sun track is corrected with this method. The operation principle of a solar-tracking sensor is introduced.
    28  Evaluation of Academic Degrees and Graduate Education Based on Neural Network
    HE De zhong LIU Jing nan ZHANG Su he
    2003, 26(5):118-120. DOI: 10.11835/j.issn.1000-582X.2003.05.029
    [Abstract](695) [HTML](0) [PDF 113.39 K](786)
    Abstract:
    With the development of the academic degrees and graduate education, evaluation is the important measure for guaranteeing the quality in the area. With increasing complication of the target of the evaluation of academic degrees and graduate education , it is necessary to introduce nonlinear method of the evaluation, which has great significance for the validity of the result of the evaluation. Neural networks have been developed greatly in recent years,they have the advantages of nonlinear mapping,parallelity ,adaption, etc. Therefore , they are good tools of nonlinear modeling. On the basis of setting up the model of the evaluation based on neural network ,this paper presets the practical value of the method.based them.
    29  Content-aware Load Balancing Strategy in Web Cluster System
    LI Shuang-qing YOU Lian CHENG Dai jie
    2003, 26(5):121-124132. DOI: 10.11835/j.issn.1000-582X.2003.05.030
    [Abstract](599) [HTML](0) [PDF 378.04 K](977)
    Abstract:
    The capacity problem of web server can be solved by web cluster technology. The key point is load balancing strategy and algorithm. Traditional slrategies are effective to some kinds of web sites, but not suitable for all. The paper analyses the load characters of different kind of web sites. A content-aware web cluster load balancing strategy and algorithm is proposed. The efficiency will be evaluated through emulation experiments.
    30  CPLD/FPGA Programmable Logic Devices'''' In System Reconfiguration Method
    HE Wei TANG Ren sheng ZHANG Ling
    2003, 26(5):125-128. DOI: 10.11835/j.issn.1000-582X.2003.05.031
    [Abstract](631) [HTML](0) [PDF 315.37 K](1294)
    Abstract:
    This article has discussed the methods of configuring the CPLD/FPGA devices based on SRAM, and choose the microprocessor to configure the FLEX10k devices of ALTERA. From the article ,we can see that this low cost and easy done method can enable the system to configure the CPLD/FPGA devices automatically as soon as the system is re set or power is re added to it. It has solved the problem that CPLD/FPGA devices based SRAM may lose it's logic function when dropped out of power, and it enables the single chip to have several functions.
    31  A Numerical Algorithms of Fractional Fourier Transform
    CHEN Ming jie
    2003, 26(5):129-132. DOI: 10.11835/j.issn.1000-582X.2003.05.032
    [Abstract](875) [HTML](0) [PDF 287.14 K](1110)
    Abstract:
    Signal and it's Fourier transform can reflect the info of time domain and frequence domain independently. As a usually math tool, Fourier transform is using in math, physical and engineering field widely. A new tool for signal analysis,which is named Fractional Fourier transform(FRFT), is introduced. It is interpreted in view of the classic Fourier transform. It is important to study the numerical algorithms of FRFT, because usually the FRFT can not be given to a analytical expression. A numerical algorithms of FRFT is given. It is possible to separate the distortion from the simple Gaussian signal on which a chirp distortion has been superimposed by using fractional transform.
    32  Zero Current Switching Multi-resonant Converters based on ConstantFrequency PWM and Mutual Inductance Technique
    GAO Chao
    2003, 26(5):133-136. DOI: 10.11835/j.issn.1000-582X.2003.05.033
    [Abstract](506) [HTML](0) [PDF 320.65 K](717)
    Abstract:
    This paper introduces a novel constant frequency switching PWM converter,as well as some improvements on the conventional bridge parallel resonant converters. By introducing mutual inductance and auxiliary into the original circuit topology ,a class of novel zero current switching multi-resonant converters regulated by PWM mode at a fixed switching frequency are presented,which overcomes some drawback of the original circuits.One illustrative example is analyzed and the experimental results are given, which confirms the advantages of this approach.
    33  Analyze the Present Status in the Calculation Methods of Lightning Protection Performance for Transmission Line
    CHEN Guo qing ZHANG Zhi jin SUN Cai xin SIMA Wen xia
    2003, 26(5):137-142. DOI: 10.11835/j.issn.1000-582X.2003.05.034
    [Abstract](1051) [HTML](0) [PDF 529.65 K](1423)
    Abstract:
    Lightning is the main reason that endangers transmission line working safety and reliabilty today. The theory and characteristic of methods that not only estimate the lightning performance for back strike such as standard method, traveling wave method, Monte Carlo technique, treeing fault method, EMTP and so on but also for the shielding failure such as standard method, EGM, leader progression model and so on are summarized. The criterion of flashover for insulators is referred simply, furthermore, it gives the opinion that the development of research for the future.
    34  Development and Application of Hydrogen Storage Alloys
    LIU Shou ping ZHAO Gang LI Rong KANG Ren mu ZHOU Shang qi REN Qin
    2003, 26(5):143-146150. DOI: 10.11835/j.issn.1000-582X.2003.05.035
    [Abstract](912) [HTML](0) [PDF 430.57 K](1664)
    Abstract:
    介绍了金属氢化反应及贮氢合金设计的基本原理,对贮氢合金的基本类型、应用状况及发展趋势进行了较全面的评述。目前已开发研究的贮氢合金品种类型虽然众多,但成熟的主要还是AB5型稀土合金。钒基固溶体合金因贮氢容量大,镁基合金固重量轻、价格低等优点在贮氢合金的开发中具有很大的潜力。贮氢合金应用领域广阔,但在很多领域的应用仍然处于试验开发阶段,只是在镍—氢化物二次电池中获得了产业化,因此贮氢合金的应用及其相关技术还有待进一步开发研究。
    35  On Electroaffinity of Atoms and Orbitals: Novel Energy Scale and Related Correlation Analysrs with Other Scales
    LIAO Chun yang LIU Zhen de HUANG Ying LI Zhi liang
    2003, 26(5):147-150. DOI: 10.11835/j.issn.1000-582X.2003.05.036
    [Abstract](860) [HTML](0) [PDF 343.83 K](1278)
    Abstract:
    Electroaffinity or electronegativity X LL is approximately proportional to the average ionization energy B , the total ionization energy U divided by the number of atomic valence shell electrons N , due to its vecy small electron affinity E . Furthermore, electroaffinity of the atomic valence and/or hybridization orbital can be also obtained from their individual capability of attracting valence electrons of an atomic valence and/or hybridization orbital by the ionization energies of valence electron in ground stated free atom and its various orbitals.
    36  The Trend of Visibility and Its Affecting Factors in Chongqing
    HONG Quan
    2003, 26(5):151-154. DOI: 10.11835/j.issn.1000-582X.2003.05.037
    [Abstract](899) [HTML](0) [PDF 339.52 K](1257)
    Abstract:
    In order to valuate the effect of air pollution countermeasures on visibility , based on the 15 year monitor data in chongqing,this paper analyses the variation trend of visibility. And the inter relationship among visibility , meteorological factors and air quality factors was also discussed by means of bivariate correlation and partial correlation. The results showed that the seasonal and annual variation of visibility is very obvious. The variation trend of visibility was first down and then up since 1980's.Wind speed can increase visibility by accelerating the transportation and dilution of pollutants and vapour; however, the increase of relative humidity, precipitation , TSP,NO X and SO 2 decrease the visibility.
    37  On Simple Groups of Orders 2a13bpcqd and 2a17bpcqd
    JIANG You yi LIU Xue fei
    2003, 26(5):155-157. DOI: 10.11835/j.issn.1000-582X.2003.05.038
    [Abstract](533) [HTML](0) [PDF 191.65 K](167)
    Abstract:
    Sinmple Groups of ordefs 2 a13 bp cq d and 2 a17 bp cq d are obtained with the theorem of classification of the simple group and the exponent Diophantine equation. With the same method, all K 4 Simple Groups of order 2 ap bq cr d(p is any definite prime except 3, q and r are any different primes unequal to p can be obtained.

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