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1998 Vol. 20, No. 6
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1998, 20(6): 721-726.
Abstract:
A new multiscale edge detection method is presented, which is based on vision feature of edge and wavelet transform. The novel features of image edge based on human being vision characters are described. The scales of wavelet transform are adjusted adaptively according to effective edge measure. Finally, experimental results are presented.
A new multiscale edge detection method is presented, which is based on vision feature of edge and wavelet transform. The novel features of image edge based on human being vision characters are described. The scales of wavelet transform are adjusted adaptively according to effective edge measure. Finally, experimental results are presented.
1998, 20(6): 727-732.
Abstract:
Clustering algorithms in feature space are important methods in image segmentation. The choice of the effective feature parameters and the construction of the clustering method are key problems encountered with clustering algorithms. In this paper we chose multifractal dimensions as the segmentation feature parameters which are extracted from original image and wavelet-transformed image. SOM network is applied to cluster the segmentation feature parameters. The experiment shows that the performance of our algorithm is very good.
Clustering algorithms in feature space are important methods in image segmentation. The choice of the effective feature parameters and the construction of the clustering method are key problems encountered with clustering algorithms. In this paper we chose multifractal dimensions as the segmentation feature parameters which are extracted from original image and wavelet-transformed image. SOM network is applied to cluster the segmentation feature parameters. The experiment shows that the performance of our algorithm is very good.
1998, 20(6): 733-738.
Abstract:
The paper describes an Adaptive Interacting Multiple-model(AIMM) algorithm for use in manoeuvring target tracking. The algorithm does not need predefined models. A two-stage Kalman estimator is used to estimate the acceleration of the target. This acceleration value is then fed to the subfilters in an Interacting Multiple Model (IMM) algorithm where the subfilters have different acceleration parameters. The simulation results of the performance of the AIMM algorithm and that of the IMM algorithm are given.
The paper describes an Adaptive Interacting Multiple-model(AIMM) algorithm for use in manoeuvring target tracking. The algorithm does not need predefined models. A two-stage Kalman estimator is used to estimate the acceleration of the target. This acceleration value is then fed to the subfilters in an Interacting Multiple Model (IMM) algorithm where the subfilters have different acceleration parameters. The simulation results of the performance of the AIMM algorithm and that of the IMM algorithm are given.
1998, 20(6): 739-744.
Abstract:
This paper presents a method to improve the estimation accuracy of a tracking Kalman filter (TKF)by using a multilayer neural network(MNN). The estimation accuracy of the TKF is degraded due to the uncertainties that cannot be expressed by the linear state-space model proposed in the literature. This fault is overcome due to the use of MNN. The results of the TKF can be modified by the treated MNN. Simulation results show that the estimation accuracy is much improved by using the MNN.
This paper presents a method to improve the estimation accuracy of a tracking Kalman filter (TKF)by using a multilayer neural network(MNN). The estimation accuracy of the TKF is degraded due to the uncertainties that cannot be expressed by the linear state-space model proposed in the literature. This fault is overcome due to the use of MNN. The results of the TKF can be modified by the treated MNN. Simulation results show that the estimation accuracy is much improved by using the MNN.
1998, 20(6): 745-749.
Abstract:
Based on a parallel uniform linear array and fourth order cumulant, a new approach for estimating multiple spatial narrow-band signal 2-D directions of arrival separately in the arbitrary Gaussian noise environment is presented. With flexible definition of fourth order cumulant of the array output signal, the spectral peak searching is not necessary for the new separable approach. Computer simulation confirms its availability.
Based on a parallel uniform linear array and fourth order cumulant, a new approach for estimating multiple spatial narrow-band signal 2-D directions of arrival separately in the arbitrary Gaussian noise environment is presented. With flexible definition of fourth order cumulant of the array output signal, the spectral peak searching is not necessary for the new separable approach. Computer simulation confirms its availability.
1998, 20(6): 750-755.
Abstract:
In this paper, a fourth-order cumulant-based ESPRIT DOA estimation method is presented for arbitrary array. The method is robust to the channel uncertainty model errors with any two channels characteristics known. The method is verified by the simulation experiments.
In this paper, a fourth-order cumulant-based ESPRIT DOA estimation method is presented for arbitrary array. The method is robust to the channel uncertainty model errors with any two channels characteristics known. The method is verified by the simulation experiments.
1998, 20(6): 756-762.
Abstract:
This paper presents some kinds of non-linear models for time series. The structure and training methods for each model have been analysed and studied. The experimental results for some common time series are given.
This paper presents some kinds of non-linear models for time series. The structure and training methods for each model have been analysed and studied. The experimental results for some common time series are given.
1998, 20(6): 763-770.
Abstract:
The properties of normal orthogonal duality of binary sequences are investigated by means of RCF of binary sequences. In order to prove the theorems given in this paper, the concept of pure code segment is introduced. And then, the relations between run numbers of pairs in duality, between run numbers of the code-bodyies of pairs in duality, and the type constants of pairs in duality are derived respectively.
The properties of normal orthogonal duality of binary sequences are investigated by means of RCF of binary sequences. In order to prove the theorems given in this paper, the concept of pure code segment is introduced. And then, the relations between run numbers of pairs in duality, between run numbers of the code-bodyies of pairs in duality, and the type constants of pairs in duality are derived respectively.
1998, 20(6): 771-774.
Abstract:
A new algorithm with the complexity O(logm) is presented to compute inverses in the finite field GF(2m) based on the normal basis representations and the Massey-Omura s multipliers. The inverse in GF(2m) can be computed with [log2(m-1)]+w(m-1)-1 multiplications and m-1 cyclic shifts, where [x] denotes the maximum integer less than or equal to x, w(m-1) the number of 1 in the binary representation of m-1.
A new algorithm with the complexity O(logm) is presented to compute inverses in the finite field GF(2m) based on the normal basis representations and the Massey-Omura s multipliers. The inverse in GF(2m) can be computed with [log2(m-1)]+w(m-1)-1 multiplications and m-1 cyclic shifts, where [x] denotes the maximum integer less than or equal to x, w(m-1) the number of 1 in the binary representation of m-1.
1998, 20(6): 775-780.
Abstract:
In this paper, the self-correlation functions of primitive M-sequences are discussed, the general solutions of some autocorrelation functions are presented. These general solutions result in that the auto-correlation functions can be obtained by the feedback functions of M-sequences and need not to know the M-sequences. Therefore, the calculation for these functions is greatly reduced. Meanwhile, potential values of autocorrelation function C(#em/em#)(n#em/em# 2n) are proposed as well.
In this paper, the self-correlation functions of primitive M-sequences are discussed, the general solutions of some autocorrelation functions are presented. These general solutions result in that the auto-correlation functions can be obtained by the feedback functions of M-sequences and need not to know the M-sequences. Therefore, the calculation for these functions is greatly reduced. Meanwhile, potential values of autocorrelation function C(#em/em#)(n#em/em# 2n) are proposed as well.
1998, 20(6): 781-786.
Abstract:
In TCP/IP networks, some routing decision and flow control algorithms can guarantee only partitioned optimazation of networks. In this paper, we use Modern Control Theory to develop a new method to judge the entir stability of date communication networks, based on the Lyapnovn Priciple and approxmation of linearized network state control model, which is a nonlinear one in the nature. Forthmore, we confirm the conclusions of TCP/IP network optimazation such as: the shotest path is available as well as the optimal routing will never from routing link loop and so on.
In TCP/IP networks, some routing decision and flow control algorithms can guarantee only partitioned optimazation of networks. In this paper, we use Modern Control Theory to develop a new method to judge the entir stability of date communication networks, based on the Lyapnovn Priciple and approxmation of linearized network state control model, which is a nonlinear one in the nature. Forthmore, we confirm the conclusions of TCP/IP network optimazation such as: the shotest path is available as well as the optimal routing will never from routing link loop and so on.
1998, 20(6): 787-793.
Abstract:
An algorithm analysing multi-output feedforward network system is discussed in this paper, the basic idea of the algorithm is to collect and utilize information leak of input information at multiple output ends. As an application, a class of important multi-output feedforward network-multi-output Bent functions is analysed by using the algorithm, and the algorithm is illustrated with a concrete example.
An algorithm analysing multi-output feedforward network system is discussed in this paper, the basic idea of the algorithm is to collect and utilize information leak of input information at multiple output ends. As an application, a class of important multi-output feedforward network-multi-output Bent functions is analysed by using the algorithm, and the algorithm is illustrated with a concrete example.
1998, 20(6): 794-798.
Abstract:
This paper introduces the concept of stability of 3-valued logical functions and examines probability characterization of stability. Criterion of stability of 3-valued logical functions is given and a typical method of constructing stable 3-valued logical funtions is presented. With the approach in this paper, the stability of P-valued logical functions may be investigated.
This paper introduces the concept of stability of 3-valued logical functions and examines probability characterization of stability. Criterion of stability of 3-valued logical functions is given and a typical method of constructing stable 3-valued logical funtions is presented. With the approach in this paper, the stability of P-valued logical functions may be investigated.
1998, 20(6): 799-805.
Abstract:
This paper presents the scheme and its implementation of a video decoder, which can complete real-time decoding the MPEG-2 based coded bit stream. This scheme adopts the parallel processing technique, the operation in pipe line and a large quantity of FPGA. The approach for the motion compensation crossing the border, which is caused by parallel processing, is studied. The architecture of the decoder, the formation of main circuits and the realization of decoding procedue are described.
This paper presents the scheme and its implementation of a video decoder, which can complete real-time decoding the MPEG-2 based coded bit stream. This scheme adopts the parallel processing technique, the operation in pipe line and a large quantity of FPGA. The approach for the motion compensation crossing the border, which is caused by parallel processing, is studied. The architecture of the decoder, the formation of main circuits and the realization of decoding procedue are described.
1998, 20(6): 806-809.
Abstract:
Three new concepts of the monostatic radar system: co-polarization match factor, cross-polarization match factor, adaptive polarization match factor, are presented. Their easily calculated expressions are given. Then the polarization corresponding to three special scattering matrices is analyzed.
Three new concepts of the monostatic radar system: co-polarization match factor, cross-polarization match factor, adaptive polarization match factor, are presented. Their easily calculated expressions are given. Then the polarization corresponding to three special scattering matrices is analyzed.
1998, 20(6): 810-814.
Abstract:
The concept of tree topology Bragg Optical Fiber Grating(BOFG) distribution sensing array is introduced.Comparing with the serrial topology array,this type of arrays has the following advantages.First,it is not necessary that the central reflecting wavelengths of all the BOFG sensors must be different.In general,they can be identical.Thus,the cost of producing the snesors can be cheaper and they will easily be commercialized;Secondly,for this type of arrays,it is likely that a large number of sensors can be employed and therefore it can be applied to large area real-time monitoring.Finally,because there is more than one optical path at the interface between the electronics and the monitored body the performance of antifailure will greatly be improved.The principle of the system construction is expounded buy a design example.According to the principle analysis and the typical parameters,the numerical results is presented and the performance of this array is analyzed.Meanwhile,some valuable conclusions are obtained.
The concept of tree topology Bragg Optical Fiber Grating(BOFG) distribution sensing array is introduced.Comparing with the serrial topology array,this type of arrays has the following advantages.First,it is not necessary that the central reflecting wavelengths of all the BOFG sensors must be different.In general,they can be identical.Thus,the cost of producing the snesors can be cheaper and they will easily be commercialized;Secondly,for this type of arrays,it is likely that a large number of sensors can be employed and therefore it can be applied to large area real-time monitoring.Finally,because there is more than one optical path at the interface between the electronics and the monitored body the performance of antifailure will greatly be improved.The principle of the system construction is expounded buy a design example.According to the principle analysis and the typical parameters,the numerical results is presented and the performance of this array is analyzed.Meanwhile,some valuable conclusions are obtained.
1998, 20(6): 815-820.
Abstract:
This papet stuides parallel EIS type light addressable semiconductor humor analysis sensor based on light addressable potentiometric sensor.The effects of the basis voltage,light modulation frequencies and light radiation power on photovoltage for the sensor with backside illumination are studied mainly.The optimized result of these parameters is given.Good response characteristics were obtained when it was used in determination of the pH(1-10pH),pO2(0.9-10ppm) and concentration of glucose (10-5～10-2M) in sample liquid.
This papet stuides parallel EIS type light addressable semiconductor humor analysis sensor based on light addressable potentiometric sensor.The effects of the basis voltage,light modulation frequencies and light radiation power on photovoltage for the sensor with backside illumination are studied mainly.The optimized result of these parameters is given.Good response characteristics were obtained when it was used in determination of the pH(1-10pH),pO2(0.9-10ppm) and concentration of glucose (10-5～10-2M) in sample liquid.
1998, 20(6): 821-827.
Abstract:
This paper combines the differential-Thompson transformation involved in hydromechanics with the finite difference time domain (FDTD) technique to form Thompson-FDTD method. This method is applied by the first time to calculate the electromagnetic scattering properties of arbitrarily shaped dielectric objects. This method has at least two obvious advantages: It can transform arbitrary shaped bodies into regular structures and thus the boundary conditions are matched accurately; it can willfully dispose the grid distribution and thus better numerical accuracy is achieved. The numerical simulation further confirms its validity.
This paper combines the differential-Thompson transformation involved in hydromechanics with the finite difference time domain (FDTD) technique to form Thompson-FDTD method. This method is applied by the first time to calculate the electromagnetic scattering properties of arbitrarily shaped dielectric objects. This method has at least two obvious advantages: It can transform arbitrary shaped bodies into regular structures and thus the boundary conditions are matched accurately; it can willfully dispose the grid distribution and thus better numerical accuracy is achieved. The numerical simulation further confirms its validity.
1998, 20(6): 828-834.
Abstract:
In this paper, asymmetrical coplanar lines in free space are analyzed using confor-mal mapping techniques, and the exact solutions are obtained. Analytic closed-form expressions for the effective dielectric constant, the capacitance per unit length, the characteristic impedance and the wavelength of guided wave for asymmetrical coplanar lines with multi-layered finite substrate thickness are obtained. The analyses are useful for the (M)MIC s designs.
In this paper, asymmetrical coplanar lines in free space are analyzed using confor-mal mapping techniques, and the exact solutions are obtained. Analytic closed-form expressions for the effective dielectric constant, the capacitance per unit length, the characteristic impedance and the wavelength of guided wave for asymmetrical coplanar lines with multi-layered finite substrate thickness are obtained. The analyses are useful for the (M)MIC s designs.
1998, 20(6): 835-839.
Abstract:
This paper presents a new numerical method, which is based on boundary element method (BEM), for the computation of resonant frequency, external Q value and field distribution of the waveguide loaded cavity. It is shown that BEM has mamy advantages as little computing time, less storage and high precision, etc. in solving the open system like waveguide loaded cavity.
This paper presents a new numerical method, which is based on boundary element method (BEM), for the computation of resonant frequency, external Q value and field distribution of the waveguide loaded cavity. It is shown that BEM has mamy advantages as little computing time, less storage and high precision, etc. in solving the open system like waveguide loaded cavity.
1998, 20(6): 840-846.
Abstract:
The concept of fault tolerance of feedforward neural networks and its contents for studying are given clearly and specially. Then, systematically and concisely, various methods for analyzing and increasing the fault tolerance of feedforward neural networks are introduced and evaluated. Finally, some main problems for further researches on the fault tolerance of feedforward neural networks are proposed.
The concept of fault tolerance of feedforward neural networks and its contents for studying are given clearly and specially. Then, systematically and concisely, various methods for analyzing and increasing the fault tolerance of feedforward neural networks are introduced and evaluated. Finally, some main problems for further researches on the fault tolerance of feedforward neural networks are proposed.
1998, 20(6): 847-851.
Abstract:
A decoding strategy for nonlinear codes using a neural network is presented. Within the capacity of error correction, it can correct and detect errors of general nonlinear codes which have some specific code distance with zero error probability. This paper describes structure of the neural network, learning algorithm and theory analysis. Finally, one decoding example: nonlinear constant weight code is demonstrated to prove the availability and values of theory and application.
A decoding strategy for nonlinear codes using a neural network is presented. Within the capacity of error correction, it can correct and detect errors of general nonlinear codes which have some specific code distance with zero error probability. This paper describes structure of the neural network, learning algorithm and theory analysis. Finally, one decoding example: nonlinear constant weight code is demonstrated to prove the availability and values of theory and application.
1998, 20(6): 852-855.
Abstract:
Emission, translation, modulation and diagnosis of short pulse intense relativistic hollow electron beams (IREBs) of a L-band relativistic klystron amplifier are described in this paper. The hollow electron beams about 500kV, 4.5kA, diameter 54.5mm, thickness 4.5mm are obtained, and 6% of beam current modulation is gotten after the electron beams get through the input cavity gap, as well as 23% of beam current modulation is gotten after the electron beams get through the idler cavity gap.
Emission, translation, modulation and diagnosis of short pulse intense relativistic hollow electron beams (IREBs) of a L-band relativistic klystron amplifier are described in this paper. The hollow electron beams about 500kV, 4.5kA, diameter 54.5mm, thickness 4.5mm are obtained, and 6% of beam current modulation is gotten after the electron beams get through the input cavity gap, as well as 23% of beam current modulation is gotten after the electron beams get through the idler cavity gap.
