Table of Content

20 December 2005 Volume 32 Issue 6

  

Original Articles

Dynamic characteristics of the analysis of stochastic chain mechanical system


CHEN Jian-jun;ZHAO Ying-ying;HUANG Ju-feng;TUO Yao-fei

J4. 2005, 32(6):  829-832. 

Abstract ( 1376 )   PDF (161KB) ( 786 )   Save

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The extended transfer matrix of the structural vibration analysis is derived by using the expansion to the transfer matrix to solve structural dynamic characteristic analysis. The algebra equation for calculating the natural frequency is estabilished by using the extended matrix and the structural boundary condition. The natural frequency can be calculated using the numerical value method for the equation and a facility method to solve the natural frequency of chain structures is obtained. Considering the randomness of the structural parameters, the model of the structural dynamic characteristic analysis is founded and the digit characteristics of the natural frequency is obtained using the Monte Carlo random simulation methods. The correctness and facility of the theory and method presented in this paper are checked by two examples. The mean value and the mean square value of the structural natural frequency are calculated, and the effect of the stochastic parameters on structural dynamic characteristic is analyzed.


A deadlock prevention policy for FMS using Petri nets in case of failures


LI Zhi-wu;DING Wei;ZHU Rong-ming

J4. 2005, 32(6):  833-838. 

Abstract ( 1697 )   PDF (302KB) ( 832 )   Save

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Abrupt failure of equipments in FMS is modeled by Petri nets, which can describe the behavior of malfunctioning equipment such as failure, recovery and rework with a failure place, a failure transition and a recovery transistion. Based on such modeling techniques, a new deadlock prevention method is presented, which controls elementary siphons only and makes dependent siphons P-invariant controlled by adjusting the control depth variables of elementary siphons. The structure of the resultant supervisors can be greatly simplified due to the fact that only the elementary siphons need to be explicitly controlled.


A novel method for fitting the distorted reflector of a large antenna


WANG Cong-si;DUAN Bao-yan;QIU Yuan-ying

J4. 2005, 32(6):  839-843. 

Abstract ( 2240 )   PDF (225KB) ( 3690 )   Save

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Based on the actual shape of a distorted reflector, a novel divided-fit method (DFM) for fitting the distorted surface of a large reflector antenna is presented by combining hoop trigonometric function fitting and quadratic radial function fitting methods, and by using the Coons surface unit to fit each zone. The results of a 7. 3-m paraboloid antenna agree well with numerical simulations and radiation patterns, and show the accurate analysis of the distorted surface can be obtained by the DFM insteadof the best-fit paraboloid method.


Low-complexity decoding of unitary space-time constellation with the circulant correlation structure


SU Xin;SUN Yong-jun;TIAN Bin;FANG Yun;YI Ke-chu

J4. 2005, 32(6):  844-847. 

Abstract ( 1684 )   PDF (177KB) ( 868 )   Save

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A modified decoding algorithm for unitary space-time codes is presented, in which the decoding search is based on the groups classified by the circulant correlation of the signal points in the constellation. The decoder estimates the group to which the received signal belongs first. The decision is made after searching in the selected group. Only the central signals of each group and the signals within the selected group are considered, and lower decoding complexity is obtained compared to maximum likelihood decoding. Simulation results show that the proposed algorithm can result in an acceptable performance with much lower decoding complexity.


The differential space-time block coding system with multiple co-channel users


LIU Qin;YANG Jia-wei;LI Jian-dong

J4. 2005, 32(6):  848-851. 

Abstract ( 1515 )   PDF (150KB) ( 838 )   Save

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After discussing the multi-user differential space-time block coding system, and analyzing the realizability of differential decoding method, we can draw the conclusion that the receiver can not decode the information of various users while the channel is unknown if multiple co-channel users in the system are synchronous. To solve this problem, a new kind of offset system structure is presented. The multiple co-channel users transmit signals nonsynchronously with different offset delays, and the receiver can iteratively subtract to get the equivalent nil-interference result, which can be disposed of with the differential method. While the multi-user system is constructed accordint to the new offset structure, the receiver can easily cancel the interference and decode the signal even if the channel state information is unknown.


Impact of convergence mechanism on self-similarity of traffic in edge nodes of optical burst switching


LIU Jian-ping;LIU Zeng-ji;WEN Ai-jun

J4. 2005, 32(6):  852-855. 

Abstract ( 1679 )   PDF (158KB) ( 844 )   Save

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Optical burst switching (OBS) is a promising paradigm of the next-generation internet infrastructure. In this paper a variance-time-based analysis method is proposed, based on the analysis of the convergence mechanism in the OBS edge node. By sampling from the traffic flow and averaging non-overlapping blocks of size m from the original series, the variance asymptotic characteristic of the averaged series is obtained, from which this method shows that the splitting, assembling and merging process of the convergence mechanism will not change the Hurst parmeter of the traffic if the queue length of assemble buffer has a finite second-order moment. A simulation model of the OBS edge node is established, on which the correctness of analysis is testified. From both theoretical and simulation results, it is demonstrated that the self-similarity of the traffic after convergence is the same as that of the input traffic and has nothing to do with the assemble algorithm.


A Web search results clustering algorithm based on fuzzy concept lattices


HUANG Jian-bin1;2;JI Hong-bing1

J4. 2005, 32(6):  856-860. 

Abstract ( 1504 )   PDF (193KB) ( 883 )   Save

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Fuzzy logic is incorporated into the Formal Concept Analysis to tackle the vague data in the formal context. A fuzzy concept lattice can be generated in the fuzzy formal context. Next, a fast fuzzy conceptual clustering algorithm is proposed to cluster the fuzzy concept lattice into conceptual clusters. Then, partial order relations are defined between the clusters for construction of the concept hierarchy. This method is applied in the Web search results clustering. Experimental results show the algorithm’s effectiveness and suitability for solving the multi-inheritance problems between conceptual clusters.


A hybrid MoM-UTD method for analyzing isolation between antennas on an electrically large conductive surface


LIU Zi-liang;ZHANG Yu;LIANG Chang-hong

J4. 2005, 32(6):  861-864. 

Abstract ( 1990 )   PDF (192KB) ( 890 )   Save

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A hybrid MoM-UTD technique is employed to accurately calculate the isolation between wire antennas mounted on a complex electrically large conductive surface combined with the reciprocity theorem. It is difficult to analyze the isolation of antennas influenced by the electrically large system only by using the method of moment (MoM). The uniform geometrical theory of diffraction(UTD) is a kind of high frequency method, and however, it has poor accuracy. The combination of MoM and UTD takes the advantages of both the methods and efficiently solves the problem of an electrically large object. The isolation between wire antennas is computed with the influence of the electrically large cylindrical surface being considered and sweep-frequency results are obtained, which can not be computed only by MoM.


Effects of random surface errors on radiation characteristics of the side-fed offset cassegrain antenna


LIU Shao-dong;JIAO Yong-chang;ZHANG Fu-shun

J4. 2005, 32(6):  865-868. 

Abstract ( 1721 )   PDF (201KB) ( 1015 )   Save

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The average power pattern of the Side-Fed Offset Cassegrain (SFOC) dual reflector antenna is analyzed, and the effect of the random surface error on radiation characteristics of the antenna is addressed. Here, the random surface error is defined as the error of the standard reflector in its normal direction and the error in a small zone of the reflector is considered as the same. We also assume that the phase error on the aperture led by the random surface error obeys the Gaussian distribution with a zero mean, under which the expression for the average power pattern is deduced. Finally, the data related to the radiation characteristics of the antenna are calculated and the corresponding curves are presented. The obtained results can be used to determine the manufacturing accuracy of the antenna’s reflectors.


Full-reference video quality assessment method based on the distortion of image content


YANG Fu-zheng1;CHANG Yi-lin1;WAN Shuai1;LUO Zhong2

J4. 2005, 32(6):  869-872. 

Abstract ( 1541 )   PDF (155KB) ( 1176 )   Save

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A new full-reference video quality assessment method is presented. The image gradient reflects the spatial structure of the image and the correlation coefficient of the image reflects the activity masking characteristic of the human visual system. Therefore, the correlation coefficient of the gradient between the reference image and the distortion image is used to assess the distortion of image content, which is combined with the luminance distortion to obtain the image quality. Experimental results illustrating the performance of the proposed method are presented and evaluated.


Fault monitoring policy for a hierarchical network with a multi-manager


ZHANG Xin1;2;CHANG Yi-lin1;SHEN Zhong1;LIU Fu-jie1;CUI Can1

J4. 2005, 32(6):  873-876. 

Abstract ( 1338 )   PDF (188KB) ( 791 )   Save

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In order to reduce the overhead caused by real-time network monitoring, a policy for fault monitoring of a hierarchical network with a multi-manager is proposed. This fault monitoring policy is based on the model of multi-agent Markov Decision Processes and makes use of the reinforcement learning mechanism. Simulation results show that the proposed scheme based on MMDP makes the network management more efficient by accurately detecting the faulty node and significantly reducing the management overhead.


The preparation and analysis of the carbon nanotube film cathode


LI De-chang1;LI Yu-kui2;3;LI Xin2;ZHU Chang-chun2

J4. 2005, 32(6):  877-880. 

Abstract ( 1415 )   PDF (141KB) ( 936 )   Save

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By using the catalyst pyrolysis method, the carbon nanotube film was prepared on the different substrate materials. Seen from the SEM and TEM photo, the prepared carbon nanotube film possesses a better directing property, uniformity and a localization growth property. The effect of the process parameter on the preparation of the carbon nanotube film is discussed. With the carbon nanotube film as cathode materials, the field emission characteristics of the carbon nanotube film cathode are presented and analyzed.


Effect of mobility on the critical transmitting range for connectivity in wireless Ad Hoc networks


ZHANG Guang-hui;LI Jian-dong;ZHOU Lei;LIU Jing

J4. 2005, 32(6):  881-884. 

Abstract ( 1847 )   PDF (171KB) ( 1018 )   Save

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The effect of mobility on the critical transmitting range in wireless Ad Hoc networks is discussed. A new parameter—the pause probability of the random waypoint mobility model (RWP) which is the deterministic parameter of the effect of mobility on the critical transmitting and reflects the stationary trend of the network is defined. And the function of the relationship of the pause probability to the minimum velocity, the maximum velocity and the pause time of RWP is derived. Simulation results show that mobility affects the critical transmitting range by pause probability. If pause probability is smaller than 0. 5, the critical transmitting range of mobile networks is 10% larger than that of stationary networks, or it equals that of a stationary one approximately.


A novel network resource allocation algorithm with load balance guarantees


SHI Yan;LIU Zeng-ji;SHENG Min

J4. 2005, 32(6):  885-889. 

Abstract ( 1711 )   PDF (226KB) ( 982 )   Save

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An efficiently used network can avoid the early emergence of network bottleneck and serve more users with QoS guarantees. In this paper, a path level resource allocation algorithm, P-ERA, is proposed first on the basis of balanced resource allocation. Based on P-ERA and with several network factors, such as link topology position and traffic injected at different source nodes, in mind, a network level resource allocation algorithm, N-ERA, is also developed, which features quantitative path selection and appropriate bandwidth allocation on constituent links along a path, the simulation results indicate that it can make full use of network resources while guaranteeing admitted services.


An adaptive ridgelet neural network model


YANG Shu-yuan;JIAO Li-cheng;WANG Min

J4. 2005, 32(6):  890-894. 

Abstract ( 1484 )   PDF (282KB) ( 820 )   Save

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By combining the ridgelet theory with the neual network, an adaptive rideglet neural network is presented by adopting a directional ridgelet function as the activation function of the hidden layer. For the stability of ridgelet in representing high dimensional data and the sparsity in approximating linear singularity (curvilinear singularity when using a multiscale ridgelet), the proposed network can learn quit a large group of multivariate functions with a reduced scale. On the other hand, it has more flexible structure, rapider processing speed, greater tolerance and robustness than the fixed ridgelet transform. Simulation results are also included to prove its efficiency.


Radar HRRP recognition based on the wavlet transform


MA Jian-hua;LIU Hong-wei;BAO Zheng

J4. 2005, 32(6):  895-900. 

Abstract ( 1882 )   PDF (252KB) ( 934 )   Save

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The Mallat tower decomposing algorithm is used to extract the feature from the High Range Resolution Profile. Two feature evaluation criteria, namely, maximum correlation coefficients criterion and Kullback-Leibler distance criterion, are used to evaluate the classification performance of coarse components and detail components of wavelet decomposing results. Simulation results based on the measured data show that the coarse components are better than the detail component in classification performance.


Algorithm and VLSI architecture for computational complexity scalable block marching motion estimation


LIU Feng;ZHUANG Yi-qi;DAI Guo-ding

J4. 2005, 32(6):  901-906. 

Abstract ( 1933 )   PDF (249KB) ( 1055 )   Save

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A computational complexity scalable algorithm(CSS) is presented for block matching motion estimation in video encoding. The CSS shares the feature of fast convergence in TSS and the advantage of center bias searching in FSS and DS, and with the uniform shape of searching pattern in algorithm, the VLSI implementation of the CSS becomes easier than that of other fast motion estimation algorithms like DS. The scalability of computation payloads has been achieved based on searching steps adjusted and block pixel sub-sampled. The proposed algorithm and architecture are suitable for the low power implementation of video encoding that needs flexible scalable capability.


An improved pre-layout wire length estimation


GAO Hai-xia;YANG Yin-tang;DONG Gang

J4. 2005, 32(6):  907-910. 

Abstract ( 1273 )   PDF (149KB) ( 754 )   Save

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Interconnection length is an important layout property of electronic designs. A reliable interconnection length estimation is essential for improving placement and routing techniques. By considerring external interconnection, an improved prior wire length estimation method is proposed. Interconnection length distribution and average interconnection length expression for external interconnection are obtained by taking into account the inherent features of the optimal placement process. By considerring both internal and external interconnections at the same time, an analytical form for the average wire length is obtained. Experimental results for several benchmark circuits show that the new method is more accurate than the Donath and Improved Donath technique by 29% and 5% respectively.


Characterizing the microcircuit process equipment based on the generalized regression neural network


YOU Hai-long;JIA Xin-zhang;ZHANG Chun-fu

J4. 2005, 32(6):  911-914. 

Abstract ( 1449 )   PDF (160KB) ( 907 )   Save

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Because of the complexity and non-linearity of microcircuit processes, the neural network method combined with the design of experiment(DOE) instead of the traditional statistical methods, is applied to the characterization of thermal oxide layer process equipments. Through only 15 experiments, the model of oxide layer thickness and uniformity is set up based on the generalized regression neural network(GRNN). The fitness and the predicting capability of the model are discussed using the function of the Signal Noise Ratio(SNR). Based on the result, the model can be used to characterize and control the process. The method could also be used for other microcircuit processes.


A high precise method for symbol timing synchronization


YI Hong-feng;GU Chun-yan;YI Ke-chu;JIN Li-jun

J4. 2005, 32(6):  915-919. 

Abstract ( 1714 )   PDF (205KB) ( 1117 )   Save

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This paper presents a high precise method for symbol timing synchronization, which is realized by using a synchronization searching/tracking loop combined with the re-sampling of the input digital signal based on a multi-phase filter-bank whose filters are deduced from a low-pass filter prototype with different group delays. The method is a fully-digitized process at the sampling clock rate, so that it can be conveniently implemented by FPGA or DSP, whose synchronization precision can reach 1% of the sampling interval.


Security analysis of Chang et al.'s signature scheme with message recovery


FU Xiao-tong;ZHANG Ning;XIAO Guo-zhen

J4. 2005, 32(6):  920-921. 

Abstract ( 2210 )   PDF (79KB) ( 964 )   Save

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Recently, C.C.Chang and Y.F.Chang have proposed a new digital signature scheme with message recovery. Neither one-way hash functions nor message redundancy schemes are used in their scheme in order to reduce the computational cost. However, it is found that their signature scheme is not as secure as they clamied, in fact. In this paper, two kinds of forgery attacks are proposed to show that an attacker can forge valid signatures on any uncontrolled messages. To overcome these attacks, the one-way hash functions and the message redundancy schemes may still be used.


An optimized algorithm for Jacobians of hyperelliptic curves


CHEN Zhi-xiong1;2;HUANG Zhen-jie1;XIAO Guo-zhen1

J4. 2005, 32(6):  922-926. 

Abstract ( 1486 )   PDF (204KB) ( 895 )   Save

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In hyperelliptic curve cryptosystems, it is one of the main steps in computing scalar multiplication to evaluate 2D+E from the given elements D and E in the Jacobian of a hyperelliptic curve. In this paper, an optimized method for computing 2D+E is proposed, which will raise the computing efficiency by about 6%~8%.


A (t,n) secret sharing scheme based on the LUC cryptosystem


PANG Liao-jun;WANG Yu-min

J4. 2005, 32(6):  927-930. 

Abstract ( 1410 )   PDF (161KB) ( 814 )   Save

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A (t,n) threshold secret sharing scheme based on the LUC cryptosystem was proposed. In the new scheme, each participant’s private-key is used as his secret share and the secret dealer does not have to distribute each participant’s secret share. All these shares are shorter than or as short as the shared secret. In the recovery phase, each cooperative participant only needs to submit a pseudo-share instead of his secret share and anyone is allowed to check whether a cooperative participant provides the true information or not immediately. The secret shares do not need to be changed when sharing multiple secrets. The security of this scheme is the same as that of the LUC cryptosystem and Shamir’s (t,n) threshold secret sharing scheme.


A new algorithm for the character segmentation of the license plate


WANG Tao;LU Zhao-yang

J4. 2005, 32(6):  931-934. 

Abstract ( 1539 )   PDF (161KB) ( 1436 )   Save

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The local and global characteristic of characters of the license plate is fully used and the concept of the similarity between a character string and the license plate is introduced, on the basis of which a new algorithm for the character segmentation of the license plate is proposed. Using connected-component searching and projection, this algorithm enumerates all the possible segmentations. And then it analyses the segmented characters using clustering. Finally, it selects a character string that has the maximal similarity to the license plate to segment the character. Experimental results show that the algorithm has good feasibility and effectiveness.


Capacity analysis of the MIMO-OFDM system over frequency- and time-selectivity fading channels


Lü Zhuo;LI Jian-dong;LI Wei-ying

J4. 2005, 32(6):  935-939. 

Abstract ( 2016 )   PDF (221KB) ( 973 )   Save

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This paper first constructs the MIMO-OFDM system model over frequency- and time-selectivity fading channels. Then the connection between selective-fading diversity and capacity is analyzed, which shows that the product of the time-selectivity order and the frequency-selectivity order is the key parameter for characterizing the outage probability and outage capacity. An equivalent analysis method is proposed to give a tight low bound of ergodic capacity. It is also shown that this low bound becomes tighter with the increasing number of transmitter antennas. Finally numerical results of outage probability and outage capacity are shown by Monte Carlo simulation.


BER performance of the precoded OFDM system over rayleigh raying channels


HE Xiu-fu1;2;LIAO Gui-sheng2

J4. 2005, 32(6):  940-943. 

Abstract ( 1867 )   PDF (182KB) ( 1097 )   Save

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There are many subchannels in the Orthegonal Frequency Division Multiplexing(OFDM). Based on the central limit theorem, the noise components of every subchannels receiver output can be shown to be the complex Gaussian with the zero mena. The error bit ratio (BER) performance formula for the block precoded OFDM system with zero forcing and squared error (MMSE) receivers in Rayleigh Raying channels is deduced in this paper. It is convenient to compare the BER performance of the different OFDM systems by the formula calculation. What is more, the actual BER obtained by the Monte Carlo simulation is identical with the BER by use of the formula.


Returned ant algorithm


XU Dian;SHI Xiao-wei;CHENG Rui

J4. 2005, 32(6):  944-947. 

Abstract ( 1519 )   PDF (158KB) ( 928 )   Save

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To overcome the drawbacks of the conventional ant colony algorithm such as slow convergence and low precision, a returned ant algorithm is proposed. To improve global convergence, an outside force makes ants move according to the whole city’s distribution. Moreover, by comparing the distances between the current position and the others, computational complexity of regional optimization is reduced. The simulation results of several traveling salesman problems show that the proposed algorithm is feasible and highly efficient.


A study of some problems in ATLAS translator design


LI Ai-ping1;2;WANG Jia-li1;DUAN Li-guo2

J4. 2005, 32(6):  948-952. 

Abstract ( 1432 )   PDF (191KB) ( 834 )   Save

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Some key problems appearing in the process of ATLAS translator design such as too great a number of ATLAS keywords, the extending problems of ATLAS in a new field, translation and interpretation of ATLAS signal related statements, and the correspondence between virtual resources and factual resources are studied. Symbol table technology is introduced to solve the capacity limitation problem of lexical analyzing tool (LEX); Both file technology and symbol table technology are used to implement the extended ATLAS problems; Database technology and Component Object Model(COM) technology are put forward to resolve the problems of signal statement translation and resources locating & calling problems in the process of signal statement translation in ATLAS. The above-mentioned methods have been applied in the project of ATLAS translator construction suceeded in the translation of related test programs in analog test field. And the ATLAS translator works well.


The upper semiconvergence of the optimal solution set of approximations for stochastic programming


HUO Yong-liang1;2;LIU San-yang1

J4. 2005, 32(6):  953-957. 

Abstract ( 1311 )   PDF (213KB) ( 827 )   Save

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The continuous convergence of the objective function sequence of approximations for stochastic programming is discussed. The convergence condition for the fesible set sequence of approximations for stochastic programming is studied. Finally, a sufficient condition for upper semiconvergence of the optimal solution set of approximations for stochastic programming is given.


A tight semidefinite relaxation for the vertex conver problem


WANG Xin-hui;LIU San-yang;LIU Hong-wei

J4. 2005, 32(6):  958-960. 

Abstract ( 1321 )   PDF (130KB) ( 864 )   Save

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A semidefinite relaxation is attained from the equivalence form for the Vertex Cover Problem in a normal way. A tight semidifinite relaxation is achieved by defining the operator hsvec. It is shown that the tight semidefinite relaxation provides a sharp lower bound. A numerical example is given.


On globally exponential convergence of a matrix differential equation


ZHANG Hai-qin;YU Li;MA Hua;REN Chun-li

J4. 2005, 32(6):  961-964. 

Abstract ( 1334 )   PDF (168KB) ( 875 )   Save

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Since a matrix differential equation is frequently a high-dimensional dynamical system, it is usually interesting and difficult to analyze its globally exponential convergence. By using the analytical method, this paper carefully investigates the globally exponential convergence of a matrix differential equation. The given exponential convergence rate is very tight.


Reliability analysis of consecutive n-1-out-of-n: G repairable systems with the multi-state component


SONG Yue;LIU San-yang;FENG Hai-lin

J4. 2005, 32(6):  965-967. 

Abstract ( 1245 )   PDF (121KB) ( 740 )   Save

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A consecutive n-1-out-of-n: G repairable system is studied. It is assumed that the working time of the components in the system is exponentially distributed, that the repair time of the component in the system is continuously distributed, and that the components in the system are subject to two kinds of failure. The system is analyzed using the vector Markov process and Laplace transformantion. The exact formulas for the Laplace transformation of the system reliability and the systems mean time to the first failure are obtained.


A boundary integral formulation for solar nonlinear force-free magnetic fields


LI Zhu-heng1;2;YAN Yi-hua2;SONG Guo-xiang1

J4. 2005, 32(6):  968-972. 

Abstract ( 1397 )   PDF (186KB) ( 798 )   Save

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A boundary integral equation for describing a nonlinear force-free magnetic field with the finite energy content in the open space above the solar surface was proposed (Yan & Sakurai, 2000), which contains the boundary magnetic field and its normal gradient under the right integral sign. We present a new direct boundary integral equation in terms of the boundary magnetic field only. While calculating magnetic field values at space points by Yan’s equation, we must first calculate the normal gradient of the magnetic field at the boundary, and it must take much time to calculate the magnetic normal gradient; but while calculating magnetic field by the new direct equation, we need not calculate the magnetic normal gradient. Compared with Yan’s equation, to calculate the field using this new equation has the advantages of speediness and nicety.


Best-fit node-state search algorithm in QoS-based networks


HAN Lin-na1;2;MA Zheng-xin2;HU Han-ying1

J4. 2005, 32(6):  973-976. 

Abstract ( 1395 )   PDF (143KB) ( 828 )   Save

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A Best-Fit Node-State Search(BFNS) algorithm is presented. The algorithm is proved to find the state of a single node from the node-state searching map that can satisfy the special QoS request at the lowest cost. The found state of the node is regarded as the most appropriate in the network in the given traffic transmission. Then an appropriate cost function can be chosen from the algorithm in order to satisfy specific QoS requriements for a given traffic.


Study of the chaotic behavior in discrete TCP-RED based on feedback control


LIU Fang

J4. 2005, 32(6):  977-981. 

Abstract ( 1463 )   PDF (219KB) ( 900 )   Save

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A discrete TCP-RED model based on feedback control is presented and the stability of the fixed points in different parameters is investigated. From the bifurcution diagram, the effects of different RED parameters disturbance on network system performance are discussed and a sufficient condition is drawn for border collision bifurcations of the system. Numerical results show that the system exhibits bifurcating and chaotic behavior. It is also shown that the system is quite sensitive to parameter variation, which is applied to adjust the parameters in TCP-RED.


Research on SoC prototype verification technology


MA Feng-xiang;SUN Yi-he

J4. 2005, 32(6):  982-986. 

Abstract ( 1547 )   PDF (219KB) ( 788 )   Save

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With Software-Compiled System Design(SCSD) Methodology as the foundation, an SoC prototype verification flow is presented,which describes the SoC prototype in Handel-C and implements it directly into prototype hardware. By using SCSD’s software tools, hardware platforms RC1000 and RC200, a prototype of the SoC prototype verification System is created. And one example that is, is also examined on it, that is, prototype verification for Lena video processing SoC, based on many experiments, the flow is improved and a new prototype board is designed.