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    20 February 2003 Volume 30 Issue 1
      
    Original Articles

    Study of the new protocols for data over SDH
    XU Zhan-qi1;MAO Qian2;WEN Ai-jun1
    J4. 2003, 30(1):  1-50. 
    Abstract ( 1717 )   Save
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    Based on the introduction of the transport protocols to transfer data over SDH, the principles and advantages and disadvantages of such protocols are discussed. The technical aspects of the latest protocol, generic framing procedure, including frame structure, laying and applications, are addressed. This paper also studies the framing efficiency of each protocol for the Internet data and IP voice packet, with some conclusions related to data over SDH presented.

    ARIMA analysis method in network traffic
    JIN Qi;PEI Chang-xing;ZHU Chang-hua
    J4. 2003, 30(1):  6-10. 
    Abstract ( 1269 )   Save
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    Traffic modeling and understanding are imperative to network design and simulation, to providing the quality of service(QoS), and to network management and control. In this paper, a practical conclusion has been arrived at that we can transform the nonstationary and growing network traffic to the domain of the stationary signal by the ARIMA modeling. By using this approach, we analyze the real traffic and the results prove the effectiveness and practicability of this approach. It is effective approach to traffic prediction in the middle/long-stage design of networks.

    New timing acquisition method for the MC-CDMA system with frequency offset
    LUAN Ying-zi;LI Jian-dong;YANG Jia-wei
    J4. 2003, 30(1):  11-152. 
    Abstract ( 1755 )   Save
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    A new method to estimate the FFT block timing offset in the MC-CDMA system is proposed. Consecutive training sequences are used to acquire the initial time synchronization. The effect of the frequency offset on this estimator is analyzed. We compared this new method with the Schmidl and Cox's method(the SC method for short) through simulation in terms of estimator mean and variance, both in the AWGN channel and in the time-varying frequency selective channel. Results show that the mean bias and variance of the new method are all less than those of the SC's method.

    Crosstalk analysis of five OXC architectures based on space switches
    HU Liao-lin;LIU Zeng-ji
    J4. 2003, 30(1):  16-19. 
    Abstract ( 1661 )   Save
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    The crosstalk of the five OXC architectures based on space switches is analyzed. Afterwards the output power equations for the five topologies are derived in the worst case. According to the equations, the total crosstalk as a function of the component(demultiplexer/multiplexer and space switches) crosstalk or the number of fibers(and the number of wavelengths) is studied in detail. From the comparison among five OXC architectures we can determine that the crosstalk performance of topology basd on separate components is the best. It is concluded that crosstalk performance of OXC depends not only on the component parameters, but also on its architecture.

    A survey of the studies on secure electronic auction
    WANG Ji-lin;CHEN Xiao-feng;WANG Yu-min
    J4. 2003, 30(1):  20-25. 
    Abstract ( 1606 )   Save
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    Electronic auction is one of the basic businesses in electronic commence. The protection of the bidder privacy and the prevention of bidder default are the key to the designing of the secure electronic auction scheme, and also problems that need to be urgently solved in the existing auction systems. This paper surveys the developments of the study on the secure electronic auction scheme. Techniques widely used in this area are introduced. Objectives of the scheme design are generalized and some typical schemes are reviewed. Finally, some problems that need to be studied further are proposed.

    A verifiable threshold signature scheme based on the elliptic curve
    HAN Jin-rong;Lü Ji-qiang;WANG Xin-mei
    J4. 2003, 30(1):  26-285. 
    Abstract ( 1817 )   Save
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    The paper presents a (t,n) verifiable threshold signature scheme based on the elliptic curve. Its security depends not only on the elliptic curve discrete logarithm but also on the choice of the elliptic curve and its system. By analyzing the scheme, we conclude that its communication complexity is lower than the scheme proposed by Kazuo etc. and its security against chosen message attack is the same as in the case of Nyberg-Rueppel signature scheme.

    The algebraic expression for the AES Sbox
    WEI Bao-dian;MA Wen-ping;WANG Xin-mei
    J4. 2003, 30(1):  29-32. 
    Abstract ( 1720 )   Save
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    The complexity and the degree of the algebraic expression for the Sbox are symbols of resistance of block ciphers against the interpolation attacks. The algebraic expression for the Rijndael Sbox has a high degree of 254 but low complexity that only nine items are there. We have investigated a new property of the finite field that the component of the field element can be expressed by a simple polynomial with the element itself as the variable. Then a new method to determine the algebraic expression for the Rijndael Sbox is proposed. Conclusions are drawn and proved that the low complexity of the algebraic expression for the Rijndael Sbox is mainly caused by the binary matrix in the construction of the Sbox and that any other choice of teh generating polynomial, the affine matrix or the affine constant will not make the expression more complex. Finally, the quideline for improvement is pointed out.

    The matching among serially concatenated space-time coding systems
    LI Ying;WANG Xin-mei
    J4. 2003, 30(1):  33-378. 
    Abstract ( 1423 )   Save
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    The diversity gain is always maximized first before coding gains are optimized in the design of a space-time coding system. The similar method is always adopted in designing the serially concatenate space-time coding system(SCST). A new optimization method for the optimization of SCST via matching the inner and outer encoder is presented. The effect of outer code redundancies on the performance of SCST is analyzed carefully. It is also pointed out that the matches between the inner and outer encoder can be acquired via the permutation of the interleaver on the outputs of the outer encoder. The work in this paper also provides the possibility to decrease the system complexity further. The siumlation results show that the matched SCST system obtains approximately 2dB gains compared with those SCSTs with available STTC in other contributions.

    The two-dimension digital image watermarking algorithm based on visual masking
    LIU Fang1;YAO Xia1;2
    J4. 2003, 30(1):  38-41. 
    Abstract ( 1505 )   Save
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    A new watermark algorithm based on visual masking in wavelet domain is proposed. Based on JEPG2000 standardization, the image and watermark are both transformed into the discrete wavelet domain. Then, the lower frequency coefficients of the watermark are embedded into those of the image with the multiresolution data fusion. Finally, the associated coefficients are restructured to obtain the embedded image. Especially, in this embedding process, the higher frequency coefficients of the watermark multiresolution data are reserved and will be used as the secret key in the detection process. In order to better fit visual masking, the behavior of the HVS to the watermarking problem in the image wavelet decomposition is used. So it can improve the invisibility and robustness. The original image is used in the proposed detection algorithm. The experimental results show that it is robust against compression, adding noise, filtering, and cropping.

    Analysis and design of the structure of micro circle-flake with the piezoelectric actuator
    JIA Jian-yuan;FAN Guo-bin;WANG Wei-dong
    J4. 2003, 30(1):  42-46. 
    Abstract ( 1841 )   Save
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    an electromechanical-coupled mechanics model is established for the circle-flake microactuator, which is based on the working principle of piezoelectricity. By using the elastic thin plate bending theory with small deflection, we derive some differential equations for the elastic curved surface in circular piezoelectric composite laminates and present an analysis and design method in which piezoelectric patch's radial strain induced by the inverse piezoelectric effect is equivalently substituted with transverse stress on piezoelectric composite laminates. It is pointed out that the equivalent transverse load depends on the edge electric field distribution of the parallel plate capacitor. The expression for the neutral plane in the piezoelectric composite laminates is derived. On obtaining the numerical solution of the transcendental equation for the electric field, a finite element structural model for the micro actuator is developed. Finally a static analysis of the model of the micropump is simulated with satisfactory results.

    An approach to suppressing meteor trails interference in the over-the-horizon radar
    QIANG Yong;JIAO Li-cheng;BAO Zheng;XING Meng-dao
    J4. 2003, 30(1):  47-50. 
    Abstract ( 1695 )   Save
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    he meteor trails often interfere with the OTH Radar in the high frequency band, which leads to the receiver of the OTH Radar not working normally. There are some special methods for eliminating underdense meteor trails inerference. However, no effective method is proposed for getting rid of long time interference caused by overdense meteor trails or the combination of several underdense meteor trails. An effective approach based on MTI filtering to eliminating nontransient meteor trails interference is presented using the theory of eigen subspace after analyzing the feature of the meteor trails in detail. Simulation results in real data show that the proposed method is efficient and practical.

    A novel method for estimating DOA in the presence of spatially nonstationary noise fields
    WU Yun-tao;LIAO Gui-sheng;ZHANG Guang-bin
    J4. 2003, 30(1):  51-54. 
    Abstract ( 2233 )   Save
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    A new method for estimating spatial narrow-band signal directions in the presence of the spatially nonstationary noise with unknown covariance is presented. An estimate of the colored noise covariance matrix is given. The received data for parameter estimation is then prewhitened using the estimated noise covariance, thus overcoming the highly biased estimates. Furthermore, its performances are confiremed by computer simulations.

    An efficient method for the design of MTI filters
    GU Hong;ZHAO Yongbo;ZHANG Shouhong
    J4. 2003, 30(1):  55-598. 
    Abstract ( 2037 )   Save
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    clutter rejection is an important problem in radar signal processing. A new method for the design of the time-varying cascaded MTI filters used in radar clutter rejection is presented in this paper. Based on the analysis of the Eigenvector method used for the design of the first filter, the new method first obtains the Doppler frequency of the moving clutter by using the nearly linear phase of the first filter. Then the weight coefficients of the second filter are obtained by the use of the table of the weight coefficients. Compared with the zero design method, the proposed method has a low computation complexity. Therefore, the proposed method is easy to implement for the practical system in real time. The design examples are presented to show that the method is effective.

    The state of arts for GaN-based blue-light-emitting diodes
    DUAN Meng;HAO Yue
    J4. 2003, 30(1):  60-65. 
    Abstract ( 1506 )   Save
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    GaN-based blue-light-emiting diodes, one of the most important applications with the GaNmaterial that we investigate, are the key color display devices. This paper introduces briefly the material characteristics of GaN, the reason GaN is suitable for blue LEDs and the typical devices which have been invented. It discusses the up-to-date GaN-based LEDs and their working mechanism in detail. From the development of blue LEDs, we can realize that luminescent spectrum and quantum efficiency are improved dramatically by changing device structures, improving material qualities or using new type material. Furthermore, some pivotal technology(including P-doping, annealing temperature, ohmic contact, etc.) in fabrications and the up-to-date state of arts for blue LEDs is discussed throughly too. Finally, the application and prospect in future about GaN based LEDs are forecasted.

    OPtimal design and manufacturability analysis of a band-pass filter
    ZENG Zhi-hua;JIA Xin-zhang;LIU Ning;LI Xiao-liang
    J4. 2003, 30(1):  66-69. 
    Abstract ( 1615 )   Save
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    Based on a band-pass filter circuit, features and functions of EDA software OrCAD/PSpice for circuit optimization are introduced. Using Parametric Swppe and Monte Carlo simulation, the circuit design is optimized and the manfacturability is analyzed. The circuit has reached design specifications and is suitable for mass production.

    Research on the noise characteristics during the electromigration process in VLSI metal interconnects
    XUE Li-jun1;DU Lei1;ZHUANG Yi-qi1;XU Zhuo2
    J4. 2003, 30(1):  70-74. 
    Abstract ( 1888 )   Save
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    Based on the accelerated life experiment and the measurement and alysis of the resistance and 1/fγ noise of metal film interconnects in VLSI with different levels of electromigration damages, we get the experimental law that the power density at 3Hz and the frequency parameter γ of 1/fγ noise become larger with the eacerbation of the electromigration damages. With the same level of electromigration damages, the relative change of 1/fγ noise is about 2000 times larger than that of resistance. For the first time, it is reported that γ becomes larger with the electromigration process. Therefore, the power density and γ of 1/fγ noise can be more sensitive parameters to represent the electromigration in metal interconnects than the parameter of resistance employed currently.

    Study of the effect of the dirstribution of pumping light on the diode pumped solid-state laser
    WANG Shi-yu1;2;XUE Hai-zhong1;TANG Ying-de1;GUO Zhen1;WEN Jian-guo1;CAI De-fang1;XIAO Bo1;ZHANG Xi-jun1
    J4. 2003, 30(1):  75-80. 
    Abstract ( 1913 )   Save
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    This paper discusses how the distribution of pumping light affect the diode pumped solid-state laser. It has been found that the dissymmetry and radium of the pumping beam are very important factors related to the determination of the threshold, output power, slope efficiency and the oscillating laser' shape. Calculation also reveals that the factor M2 is not adequate to appraising a pumping system's quality.

    Nonuniformity correction of infrared image sequences based on the scene moving analysis
    JIANG Guang;ZHOU Hui-xin;WANG Bing-jian;LIU Shang-qian
    J4. 2003, 30(1):  81-84. 
    Abstract ( 1936 )   Save
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    A new IRFPA nonuniformity correction algorithm is developed, based on the scene moving analysis. The correction procedure is to find the relationship between every two detectors using block matching of image sequence, and the matching information comes from the character of detectors' output signal along the time axis. The algorithm can not only adapt to the slow change of nonuniformity with time and with external conditions, but also eliminate the ghost that always apears in normal sence-based NUC analysis. The simulation results and the error analysis are also given.

    Intrusion-tolerant based architecture for database system security
    ZHU Jian-ming1;2;MA Jian-feng1
    J4. 2003, 30(1):  85-89. 
    Abstract ( 1455 )   Save
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    This paper proposes an architecture for database system security based on intrusion-tolerant mechanisms. The architecture is built on three layers security model, which is to defense intrusion in the outer lyaer, to detect intrusion in the middle layer, and to tolerate intrusion in the inner layer. We utilize the techniques of both redundancy and diversity and threshold secret share schemes to implement the survivability of databases and to protect confidential data from compromised servers in the presence of intrusions. Compared with the existing schemes, our approach has realized the security and robustness for the key functions of a database system by using the integration security strategy and multiple security measures.

    Research on the intger-to-integer wavelet-coefficient-based texture image retrieval techniques
    TIAN Yu-min1;NAI Xue-shang1;GAO You-xing1;SONG Xiao-xue2
    J4. 2003, 30(1):  90-93. 
    Abstract ( 1865 )   Save
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    A texture image retrieval method using the ingeger-to-integer wavelet coefficient is proposed. As the main features of teh texture image are present in the details and the high pass of the WT coefficients denotes the details of the image, the features deduced from WT Coefficients can be used to retrieve the texture image. Better indexing results can be obtained based on this method, which are not sensitive to luminance. These virtues cannot be found in the traditional literature.

    Multiple factor synthetic decision algorithm for radar/ESM correlation
    LIU Cheng-xia;WANG Bao-shu
    J4. 2003, 30(1):  94-96. 
    Abstract ( 1850 )   Save
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    In the Multi-sensor Information Fusion system the association of ESM data and radar data is a very important part. As the environment becomes more and more complex, the traditional correlation, which use the azimuth as the basis of correlation, can not satisfy the demand of the system. To solve this problem, a new correlation alroithm-Multiple Factor Synthetic Decision Algorithm(MFSDA) is developed in this paper. In the MFSDA, besides the azimuth, the high accurate attribute parameters from the ESM sensor are also considered as the precondition for attribute-track correlation. All the parameters are synthesized into a synthetic function, which is the core of teh MFSDA. If the value of the synthetic function is under the validation gate, the correlation comes into existence. By using the MFSDA the correct association rate is high.

    A study of the implementation of the precompiler for embedding the rule-based paradigm into the object-oriented language
    LIU Xiao-jian;LIU Xi-yang;CHEN Ping
    J4. 2003, 30(1):  97-102. 
    Abstract ( 1370 )   Save
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    Traditional rule-based tools, such as OPS5, CLIPS, etc. are standalone, so it is difficult to intgrate them into an actual system coded with the C++ language. Based on ILOG Rules and CLIPS, a rule language embedded into the C++ is designed and a precomplier which translates this rule language into the C++ source is implemented in this paper. The designed rule language enhances the ability of cooperation between rule and C++ language in two aspects: one is that the rule can be embedded directly into LHS and RHS, and the other is to allow AND and OR pattern grouping in LHS.

    Analysis of the finite element and reliability for stochastic truss structures
    MA Hong-bo;CHEN Jian-jun;CUI Ming-tao;GAO Wei;LIU Wei
    J4. 2003, 30(1):  103-107. 
    Abstract ( 1804 )   Save
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    This paper deals mainly with the analysis method of teh finite element and reliability for truss structures with random parameters under random loads action. The stochastic factors of the structural physical parameters, geometry dimensions and the stochastic loads applied on structures are considered respectively or simultaneously in the analysis. The algebra synthesis method is employed to obtain the computational expressions for the numerical characteristic of the structural responses(displacements and stresses). And then the reliability indexes of the structural responses are obtained. Finally, the rationality and the feasibility of the method are confirmed by an example.

    Overview of the mechanisms and applications of the scanning probe microscope series
    TIAN Wen-chao;JIA Jian-yuan
    J4. 2003, 30(1):  108-112. 
    Abstract ( 1433 )   Save
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    The Scanning Probe Microscope(SPM), which was invented for imaging the topographic at the atomic level, becomes a method for manipulating the single atom and fabricating nanometer-scale structures on the solid surface and for the realization of single-atom and single-electron devices. This capability makes it increasingly attractive and powerful for use in diverse areas, such as gene engineering, life science, material science, biotechnology and surface technology. The histories of the Scanning Probe icroscopy are introduced in this paper, followed by the principles, characteristics, actual conditions and applications. Its applications in single atom mainpulation, life science and information science are emphasized. Finally the research directions are put forward.

    Study of the dual-band internal handset antenna with a new structure
    PENG Hong-li;ZHANG Hou;LIU Qi-zhong
    J4. 2003, 30(1):  113-116. 
    Abstract ( 1497 )   Save
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    A new novel structure of miniaturized dual-band internal handset antenna is presented. Emphasis is placed on the characteristics of its Voltage Standing Ratio(VSWR) and beam pattern which are investigated by both the numerical technique of the moment method(MoM) and the Dyadic Greens function method and experiments. The results show the validity of the method and that the antenna with features of a dual band, a low VSWR and a low Specific Absorb Ratio(SAR) will find wide applications in handset systems.

    Study of the inertia parameter measurement in telemetering for guided bombs with a wavelet de-noise technique
    GUI Yan-ning1;JIAO Li-cheng1;ZHANG Fu-shun2
    J4. 2003, 30(1):  117-119. 
    Abstract ( 1470 )   Save
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    The noise in the inertia parameter measurement in telemetering for bombs is discussed with the theory of wavelet. The principle and the engineering realization method for the de-noise with the theory of wavelet are given. The method is used for a practical system of inertia parameter measurement in some flight test at range. The measurement results are in good agreement with the theoretical design ones.

    A study of the optimal quantity of items for internet-based auctions
    DU Li;HU Qi-ying
    J4. 2003, 30(1):  120-124. 
    Abstract ( 1535 )   Save
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    Based on the auction formalism in Onsale, Inc., an Internet-based auction house, we study the following optimization problem: here a given total number of iterms should be sold in a given time horizon, which is divided into serveral time periods and at each period there is an auction to sold the items offered optimally. The remaining items at each period can be sold at the next period until the time horizon is ended. It is formulated as a Markov decision process and its optimality equuation is solved numerically. It is shown that the expected total profit is superior to the original one.

    American option pricing of a special model
    YAN Hai-feng1;2;LIU San-yang1
    J4. 2003, 30(1):  125-127. 
    Abstract ( 1357 )   Save
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    The problem of an American option pricing is considered in the financial market model of discrete time. Under the conditions of stock price submitting to the exponential hypothesis we obtain an upper bound of the value of the American option on this stock price by using the martingale method of option pricing. The upper bound is irrelative to the time selected by the holder, and hence it can give the option writer an estimation to assets his average loss.

    The fast algorithms for finding the inverses and generalized inverses of resultant matrices
    GAO Shu-ping;LIU San-yang
    J4. 2003, 30(1):  128-132. 
    Abstract ( 1510 )   Save
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    A fast algorithm for calculating the inverse and group inverse and Moore-Penrose inverse of a resultant matrix is presneted by using the fast algorithm for finding polynomials. Only the rounding error exists when the fast algorithm is realized by computers, and only the entries in the first row of the resultant matrix is used in this algorithm, so the computing results are accurate in theory.

    Complete hypersurface in a locally symmetric manifold
    SHU Shi-chang1;2;LIU San-yang1
    J4. 2003, 30(1):  133-135. 
    Abstract ( 1436 )   Save
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    1The complete minimal hypersurfaces in a Locally symmetric manifold Nn+1 are studied, with some characteristics of these hypersurfaces obtained by using the generalized maximal principle. It is shown that if M is a complete minimal hypersurface in Nn+1, then M is totally geodesic or sup S is not less than (2δ-1)n. And it is shown furture that M is totally geodesic or is the product of Riemannian Manifold of m dimensional and n-m dimensional, whose constant sectional curvature is n/m and m/(n-m), respectively; or sup S is larger than (2δ-1)n. These results generalize the result of Shui N.X. and improve the result of Hineva S.

    A hierarchical filtering algorithm for processing distance images
    SHEN Yan;YANG Zhi-qing
    J4. 2003, 30(1):  136-140. 
    Abstract ( 1718 )   Save
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    The distance image means the one formed by distance measuring based on pulse rejection combined with beam scanning, whose statistical property is usually different from that of the conventional optical image. This paper proposes a hierarchical filtering algorithm for processing distance images, which can, compared with the conventional methods, remove noise more effectively and obtain images with clearer objects and background. It segments an image by taking advantage of the static characteristic of a distance image and filtering respectively, and then synthesizes to reconstitute a new image. Experimental results suggest that the algorithm behaves well and is suitable for DSP implementation in real time.
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