ISSN 
2005 Vol. 34, No. 6
2005, 34(6): 729-731,746.
Abstract:
In this paper, an algorithm is proposed to estimate the Linear Frequency-Modulated (LFM) signal's parameters under non-gauss noise condition. By analyzing the characteristics of impulse noise, a modified lower-order-moments ambiguity function is presented, which can analyze the time-frequency trait even under the impulse noise condition. Moreover, the proposed method combines the Radon transform to estimate the LFM signal's parameters, which can suppress noise further. This approach can be applied in the impulse noise case or in the gauss noise case, hence it possesses the better robust property than the conventional methods. At last, the performance of the proposed scheme is compared with the conventional method, and the computer simulation results show the effectiveness of the new method.
In this paper, an algorithm is proposed to estimate the Linear Frequency-Modulated (LFM) signal's parameters under non-gauss noise condition. By analyzing the characteristics of impulse noise, a modified lower-order-moments ambiguity function is presented, which can analyze the time-frequency trait even under the impulse noise condition. Moreover, the proposed method combines the Radon transform to estimate the LFM signal's parameters, which can suppress noise further. This approach can be applied in the impulse noise case or in the gauss noise case, hence it possesses the better robust property than the conventional methods. At last, the performance of the proposed scheme is compared with the conventional method, and the computer simulation results show the effectiveness of the new method.
2005, 34(6): 732-735.
Abstract:
In this paper, the distributing rules of spurs in the DDS output spectrum is analyzed. A effective method to design reasonable external circuits and choose appropriate instruction words is presented to improve the spectrum purity of the LFM signal. DDS chip (AD9854) is used to generate a broad band LFM signal. The experiments result shows that the LFM signal can achieve 62 dB SFDR with using this method in 30 MHz bandwidth. It increases the SFDR in about 10 dB than that without using this method.
In this paper, the distributing rules of spurs in the DDS output spectrum is analyzed. A effective method to design reasonable external circuits and choose appropriate instruction words is presented to improve the spectrum purity of the LFM signal. DDS chip (AD9854) is used to generate a broad band LFM signal. The experiments result shows that the LFM signal can achieve 62 dB SFDR with using this method in 30 MHz bandwidth. It increases the SFDR in about 10 dB than that without using this method.
2005, 34(6): 736-738,758.
Abstract:
The parallel time-interleaved ADC is an effective method to improve sample-rate. However, channel mismatches lead to nonuniform sampling and degrades the performance of the whole ADC system. After analyzing the signal spectrums, this paper proposed a method to measure and verify the time-skew errors. The experiment results show that the method can calibrate the spectrums effectively.
The parallel time-interleaved ADC is an effective method to improve sample-rate. However, channel mismatches lead to nonuniform sampling and degrades the performance of the whole ADC system. After analyzing the signal spectrums, this paper proposed a method to measure and verify the time-skew errors. The experiment results show that the method can calibrate the spectrums effectively.
2005, 34(6): 739-742.
Abstract:
The paper considers the anti-jamming of SAR,based on the analyzing jiamming methods in existence, puts forward a new jamming which is a time, frequency and dopple fields multidimensional-overcast similar clutter's jamming. Through the Zero Memory NonLinearity (ZMNL) method, generates of the correlated log normal, Weibull and K-distributed clutter vectors, and deeply researchs the method of similar clutter jamming based on the digital frequency memorizer. Finally, this method is proved to be effectual to SAR jamming through the matlab emulators. By using the similar jamming signal to the SAR, the method can receive the SAR's process gains and reduce the jamming energy. Compared with cheat jamming, it may reduce the need for the parameters's precision, so it is realizable.
The paper considers the anti-jamming of SAR,based on the analyzing jiamming methods in existence, puts forward a new jamming which is a time, frequency and dopple fields multidimensional-overcast similar clutter's jamming. Through the Zero Memory NonLinearity (ZMNL) method, generates of the correlated log normal, Weibull and K-distributed clutter vectors, and deeply researchs the method of similar clutter jamming based on the digital frequency memorizer. Finally, this method is proved to be effectual to SAR jamming through the matlab emulators. By using the similar jamming signal to the SAR, the method can receive the SAR's process gains and reduce the jamming energy. Compared with cheat jamming, it may reduce the need for the parameters's precision, so it is realizable.
2005, 34(6): 743-746.
Abstract:
It is important that the high speed sampling data must be downconverted fast in the study of the wideband digital receiver. Based on DFT filter banks, an efficient structure of wideband digital downconverter,which can realize the Digital Down Conversion(DDC) and sampling rate change (SRC) of wideband signal, and multiple signals can also be processed easily in parallel form,is presented in this paper. Using the single level multiplication and parallel form in this structure, the computational time and hardware source exhaustion can be reduced. Algorithm and its FPGA implement computer simulation confirm the effectiveness of this structure.
It is important that the high speed sampling data must be downconverted fast in the study of the wideband digital receiver. Based on DFT filter banks, an efficient structure of wideband digital downconverter,which can realize the Digital Down Conversion(DDC) and sampling rate change (SRC) of wideband signal, and multiple signals can also be processed easily in parallel form,is presented in this paper. Using the single level multiplication and parallel form in this structure, the computational time and hardware source exhaustion can be reduced. Algorithm and its FPGA implement computer simulation confirm the effectiveness of this structure.
2005, 34(6): 747-750.
Abstract:
Aiming at that the π/4-DQPSK digital modulation need large amount of operation and fast modulation is achieved difficultly. A fast arithmetic based on digital modulation is present in this paper. The arithmetic bases on TMS320C54x DSP processor. Difference coding and signal mapping is completed by look-up tables, Shaping FIR filtering for channel I and Q is completed by wave storage and Carrier modulation is completed by strobe and reading directly. There are no multiplications in whole modulation. The speed of modulation is faster. Simulating result proves the effectivity of the arithmetic.
Aiming at that the π/4-DQPSK digital modulation need large amount of operation and fast modulation is achieved difficultly. A fast arithmetic based on digital modulation is present in this paper. The arithmetic bases on TMS320C54x DSP processor. Difference coding and signal mapping is completed by look-up tables, Shaping FIR filtering for channel I and Q is completed by wave storage and Carrier modulation is completed by strobe and reading directly. There are no multiplications in whole modulation. The speed of modulation is faster. Simulating result proves the effectivity of the arithmetic.
2005, 34(6): 751-754.
Abstract:
In this letter, we propose a soft/cancellation turbo equalization scheme to suppress cochannel interference(CCI) in space code systems. It is shown that the proposed method can effectively suppress CCI while preserving the space-time structure, without increasing receiver antenna, thereby significantly improving the system's interference suppression ability. The results of simulation express that the scheme can depress error bits rate when there is one or two CCI in the system.
In this letter, we propose a soft/cancellation turbo equalization scheme to suppress cochannel interference(CCI) in space code systems. It is shown that the proposed method can effectively suppress CCI while preserving the space-time structure, without increasing receiver antenna, thereby significantly improving the system's interference suppression ability. The results of simulation express that the scheme can depress error bits rate when there is one or two CCI in the system.
2005, 34(6): 755-758.
Abstract:
This paper briefly talks about the principle of distributed arithmetic algorithm and its application to the multiply-accumulate before puts forward a improved distributed arithmetic algorithm which suits the look up table structure of filed programmable gate array well. Simulated and tested results on real device shows that high efficient and real-time decimation filter with some invariable pipeline delay can be achieved through this improved algorithm. The fabricated decimation filters are used in real digital receiver.
This paper briefly talks about the principle of distributed arithmetic algorithm and its application to the multiply-accumulate before puts forward a improved distributed arithmetic algorithm which suits the look up table structure of filed programmable gate array well. Simulated and tested results on real device shows that high efficient and real-time decimation filter with some invariable pipeline delay can be achieved through this improved algorithm. The fabricated decimation filters are used in real digital receiver.
2005, 34(6): 759-762.
Abstract:
A new scheme of the parallel realization of MUSIC algorithm on high speed signal processor is focused in this paper. Some results from effective pre-processing methods given in this paper benefit reducing computational complexity and improving process speed. At last, some new parallel analysis methods are provided for the realization of MUSIC algorithm in FPGA in this paper. It is proved that the method is good at speed and can be applied to real-time practice.
A new scheme of the parallel realization of MUSIC algorithm on high speed signal processor is focused in this paper. Some results from effective pre-processing methods given in this paper benefit reducing computational complexity and improving process speed. At last, some new parallel analysis methods are provided for the realization of MUSIC algorithm in FPGA in this paper. It is proved that the method is good at speed and can be applied to real-time practice.
2005, 34(6): 763-766.
Abstract:
The method of multi-chaos time division synchronization is proposed and the theory bases of many single chaotic synchronized systems making up of one multi-chaos synchronized system are attested by which it is achieved that the drivers and responses of many chaotic systems form one multi-chaos synchronized system with one synchronized channel between them used by their discrete synchronized signals in time divisional method. Then, based on the unifying chaotic systems, three chaotic time division usage systems are simulated. Finally, this paper summarizes the condition of multi-chaos time division synchronization and its application in secure communication.
The method of multi-chaos time division synchronization is proposed and the theory bases of many single chaotic synchronized systems making up of one multi-chaos synchronized system are attested by which it is achieved that the drivers and responses of many chaotic systems form one multi-chaos synchronized system with one synchronized channel between them used by their discrete synchronized signals in time divisional method. Then, based on the unifying chaotic systems, three chaotic time division usage systems are simulated. Finally, this paper summarizes the condition of multi-chaos time division synchronization and its application in secure communication.
2005, 34(6): 767-770.
Abstract:
High Range Resolution (HRR) Moving Target Indicator (MTI) is becoming important for many military civil, such as the detection and classification of moving targets in strong clutter background. We consider the problem of extracting the HRR features of moving targets with very closely spaced scatters in the presence of strong stationary clutter. After setting up and analysing mathematics model of strong clutter background, we analyse this kind of concretppler frequee course of MOVER algorithm on the basis of relaxing algorithm. In this algorithm, we detaile range migration and doncy of moving targets. Numerical results have shown that the proposed algorithm exhibits super-resolution and estimation performance.
High Range Resolution (HRR) Moving Target Indicator (MTI) is becoming important for many military civil, such as the detection and classification of moving targets in strong clutter background. We consider the problem of extracting the HRR features of moving targets with very closely spaced scatters in the presence of strong stationary clutter. After setting up and analysing mathematics model of strong clutter background, we analyse this kind of concretppler frequee course of MOVER algorithm on the basis of relaxing algorithm. In this algorithm, we detaile range migration and doncy of moving targets. Numerical results have shown that the proposed algorithm exhibits super-resolution and estimation performance.
2005, 34(6): 771-773,849.
Abstract:
A method based on least-squares curve fitting is introduce to acquired the information of velocity of the pulsed laser radar's object. The exponential function and the orthogonal function are taken as fundus to fit curve respectively, and their fitting performance have been compared by the analysis of the measuring deviation of them, and then choose the exponential function is chose as fundus to fit curve to acquire the information of velocity of object.
A method based on least-squares curve fitting is introduce to acquired the information of velocity of the pulsed laser radar's object. The exponential function and the orthogonal function are taken as fundus to fit curve respectively, and their fitting performance have been compared by the analysis of the measuring deviation of them, and then choose the exponential function is chose as fundus to fit curve to acquire the information of velocity of object.
2005, 34(6): 774-777.
Abstract:
A simple analysis is made of the superluminal group velocity. The anomalous propagation of an electromagnetic Gaussian pulse through a waveguide with piecewise different dielectric constants is simulated. At the same time, the group velocity and energy velocity of Gaussian wave packet through cutoff region are calculated. And, the "superluminal" problem is analyzed involved in it. From the result of simulating, it is gained that when the length of cutoff region and the work frequency are in one range, group velocity is greater than the light speed in vacuum. But energy velocity is smaller than the light speed in vacuum all long.
A simple analysis is made of the superluminal group velocity. The anomalous propagation of an electromagnetic Gaussian pulse through a waveguide with piecewise different dielectric constants is simulated. At the same time, the group velocity and energy velocity of Gaussian wave packet through cutoff region are calculated. And, the "superluminal" problem is analyzed involved in it. From the result of simulating, it is gained that when the length of cutoff region and the work frequency are in one range, group velocity is greater than the light speed in vacuum. But energy velocity is smaller than the light speed in vacuum all long.
2005, 34(6): 778-781.
Abstract:
This paper defines the adjacent cost matrix and the path matrix based on the directed weighted-graph, and defines a new operator that "summarization then minimum" replace "multiplication then summarization" between two adjacent cost matrixs, named "minimum of summarization sequence between two multiplication position elements of the two matrixs". Based on this new matrix operator, this paper proposes a new algorithm to the shortest path problem within a directed graph. This algorithm can get the global shortest path out for any types of graph. Dijkstra algorithm is a well-known good solution to the shortest path problem, but it will result out a fake path to some kinds of graph. The algorithm presented by this paper completely overcome this phenomena out of Dijikstra algorithm.
This paper defines the adjacent cost matrix and the path matrix based on the directed weighted-graph, and defines a new operator that "summarization then minimum" replace "multiplication then summarization" between two adjacent cost matrixs, named "minimum of summarization sequence between two multiplication position elements of the two matrixs". Based on this new matrix operator, this paper proposes a new algorithm to the shortest path problem within a directed graph. This algorithm can get the global shortest path out for any types of graph. Dijkstra algorithm is a well-known good solution to the shortest path problem, but it will result out a fake path to some kinds of graph. The algorithm presented by this paper completely overcome this phenomena out of Dijikstra algorithm.
2005, 34(6): 782-785.
Abstract:
This paper discuss the key techniques used in Stroke to Raster Scan Conversion(SRC). The fundamentals of video scan conversion. A practical scan conversion system based on CPLD is proposed, in which CPLD is used to control SRC system flexibly and it realizes stroke to taster scan display system conversion. The results are useful to the video conversion field.
This paper discuss the key techniques used in Stroke to Raster Scan Conversion(SRC). The fundamentals of video scan conversion. A practical scan conversion system based on CPLD is proposed, in which CPLD is used to control SRC system flexibly and it realizes stroke to taster scan display system conversion. The results are useful to the video conversion field.
2005, 34(6): 786-789.
Abstract:
With the terminal on satellite in the orbital motion thermal condition, optical antenna mirror surface thermal distortion will badly affect the performance of laser communications links. Applying finite element method to analyze shows that normal angle deviation of mirror body before and after thermal tension being released can be nearly 3 order magnitude which is 10-7 radian when reasonable application of pressing-plate method. Pressing-plate method is, in certain condition, a more optimum solution of fixing method to the working way of terminal on satellite in space-to-ground laser communication links.
With the terminal on satellite in the orbital motion thermal condition, optical antenna mirror surface thermal distortion will badly affect the performance of laser communications links. Applying finite element method to analyze shows that normal angle deviation of mirror body before and after thermal tension being released can be nearly 3 order magnitude which is 10-7 radian when reasonable application of pressing-plate method. Pressing-plate method is, in certain condition, a more optimum solution of fixing method to the working way of terminal on satellite in space-to-ground laser communication links.
2005, 34(6): 790-793.
Abstract:
Considering the shortage of application-specific pseudo-random sequence generator, the characteristics of pseudo-random sequence and its generation principle based on high-speed data generator are discussed in details in this paper. High-speed data generator based pseudo-random sequence generation is one of the development directions of data domain test. A few kinds of patterns of pseudo-random sequences and the methods of their generation are described first. Then the basic principle of the generation is introduced. And the implementation of typical pseudo-random sequence is presented. The experiment result is given.
Considering the shortage of application-specific pseudo-random sequence generator, the characteristics of pseudo-random sequence and its generation principle based on high-speed data generator are discussed in details in this paper. High-speed data generator based pseudo-random sequence generation is one of the development directions of data domain test. A few kinds of patterns of pseudo-random sequences and the methods of their generation are described first. Then the basic principle of the generation is introduced. And the implementation of typical pseudo-random sequence is presented. The experiment result is given.
2005, 34(6): 794-797.
Abstract:
The basic feature and design method of MMW TWTs electronic optics system are analyzed in this paper. A method of investigation the beam static characteristics is described using Particle-In-Cell (PIC) simulation and electronic optics model integrated electron gun with periodic permanent magnetic focusing system. It is valuable for achieving the goal of "first-pass design success" and the electronic optics system engineering design and optimization.
The basic feature and design method of MMW TWTs electronic optics system are analyzed in this paper. A method of investigation the beam static characteristics is described using Particle-In-Cell (PIC) simulation and electronic optics model integrated electron gun with periodic permanent magnetic focusing system. It is valuable for achieving the goal of "first-pass design success" and the electronic optics system engineering design and optimization.
2005, 34(6): 798-801.
Abstract:
In this paper, the automaton that is to base on the combination of fuzzy processing and neural network is constructed successfully. At the same time, fuzzy geometrical features are processed by using fuzzy technology from images of unprocessed electromagnetic wave (simplifying wave of signal), and the wave of signal is classified and recognized. The fuzzy geometrical features are found to be the best for recognizing distorted overlapping waves of signal when Fuzzy Automata (FA) are used. The overall performance is best of FA.
In this paper, the automaton that is to base on the combination of fuzzy processing and neural network is constructed successfully. At the same time, fuzzy geometrical features are processed by using fuzzy technology from images of unprocessed electromagnetic wave (simplifying wave of signal), and the wave of signal is classified and recognized. The fuzzy geometrical features are found to be the best for recognizing distorted overlapping waves of signal when Fuzzy Automata (FA) are used. The overall performance is best of FA.
2005, 34(6): 802-805.
Abstract:
A very fast algorithm to perform pattern matching in strings was described. The proposed match algorithm combines the advantages of Karp-Rabin's algorithm and Boyer-Moore's algorithm. Instead of checking at each position of the text if the pattern occurs, it is only to check the resemblance between the contents of the string and the pattern by using a hashing function and can skips as many characters as possible. In the cases of short patterns its time complexity can theoretically reach O(n) even in the worst cases. In actual experiments, the time it takes to search a string is about 1/10 of the time KR algorithm takes.
A very fast algorithm to perform pattern matching in strings was described. The proposed match algorithm combines the advantages of Karp-Rabin's algorithm and Boyer-Moore's algorithm. Instead of checking at each position of the text if the pattern occurs, it is only to check the resemblance between the contents of the string and the pattern by using a hashing function and can skips as many characters as possible. In the cases of short patterns its time complexity can theoretically reach O(n) even in the worst cases. In actual experiments, the time it takes to search a string is about 1/10 of the time KR algorithm takes.
2005, 34(6): 806-808.
Abstract:
This paper presents a novel global trust model based on confirmation theory. The reputation is calculated by C-F model according to the bartering history, and then the peer decides to download the sharing file from which the peer has good reputation. Analyses and simulations show that the model can discard the malicious peer from peer-to-peer system effectively and improve the rate of successful barter greatly.
This paper presents a novel global trust model based on confirmation theory. The reputation is calculated by C-F model according to the bartering history, and then the peer decides to download the sharing file from which the peer has good reputation. Analyses and simulations show that the model can discard the malicious peer from peer-to-peer system effectively and improve the rate of successful barter greatly.
2005, 34(6): 809-812.
Abstract:
Object-Oriented Risk Assessment Methodology and Simulation Model (ORASM) combined the object-oriented analysis method with event tree analysis and discrete event simulation. By introduced the two response modes to event and probabilistic branch, the risk of the systems, in which events and their response are time dependent and are undetermined, can be assessed and simulated effectively by ORASM. It is applied to an aviation safety problem that considers mechanisms by which an aircraft might become involved in a runway incursion incident.
Object-Oriented Risk Assessment Methodology and Simulation Model (ORASM) combined the object-oriented analysis method with event tree analysis and discrete event simulation. By introduced the two response modes to event and probabilistic branch, the risk of the systems, in which events and their response are time dependent and are undetermined, can be assessed and simulated effectively by ORASM. It is applied to an aviation safety problem that considers mechanisms by which an aircraft might become involved in a runway incursion incident.
2005, 34(6): 813-816.
Abstract:
An ad hoc network is a collection of wireless mobile hosts, which can form a temporary network without the aid of any infrastructure or centralized administration. After the MAC protocol of ad hoc network is studied and the protocol of WTRP is improved and modified, a new uncontested Distributed Parallel Wireless Token Ring Protocol (DPWTRP), which can ensure MAC(Media Access Control) layer QoS for ad hoc network, is presented. The simulation results show that the average delay and queue length in DPWTRP system are much lower than in WTRP system, and the stability is more enhanced. As a result, it could be more fit for the services which require the lower delay.
An ad hoc network is a collection of wireless mobile hosts, which can form a temporary network without the aid of any infrastructure or centralized administration. After the MAC protocol of ad hoc network is studied and the protocol of WTRP is improved and modified, a new uncontested Distributed Parallel Wireless Token Ring Protocol (DPWTRP), which can ensure MAC(Media Access Control) layer QoS for ad hoc network, is presented. The simulation results show that the average delay and queue length in DPWTRP system are much lower than in WTRP system, and the stability is more enhanced. As a result, it could be more fit for the services which require the lower delay.
2005, 34(6): 817-820.
Abstract:
Competitive advantage of Artificial Neural Network (ANN) compensation control is that it can overcome the time delay, which is of vital importance in process control. ANN identify time lag in the system, and is modified through error compensation method. Feedback of control system comes from the output of nonlinear ANN without time lag. Predictive control strategy is used to improve the performance of overall system. Simulation test shows the algorithm has little response time and strong adaptability and robustness; it can overcome the degradation introduced by time delay and disturbance in system; fine performance of control is acquired.
Competitive advantage of Artificial Neural Network (ANN) compensation control is that it can overcome the time delay, which is of vital importance in process control. ANN identify time lag in the system, and is modified through error compensation method. Feedback of control system comes from the output of nonlinear ANN without time lag. Predictive control strategy is used to improve the performance of overall system. Simulation test shows the algorithm has little response time and strong adaptability and robustness; it can overcome the degradation introduced by time delay and disturbance in system; fine performance of control is acquired.
2005, 34(6): 821-824.
Abstract:
Based on the research of black box testing of the embedded software, a new test case generation algorithm is proposed. This algorithm, based on the principles of pairwise testing, considers all possible values and their combinations on extern interfaces of a system. Experiments results show that this algorithm improves the efficiency of test case generation without any influence on the precision of software test.
Based on the research of black box testing of the embedded software, a new test case generation algorithm is proposed. This algorithm, based on the principles of pairwise testing, considers all possible values and their combinations on extern interfaces of a system. Experiments results show that this algorithm improves the efficiency of test case generation without any influence on the precision of software test.
2005, 34(6): 825-827.
Abstract:
The foundation of Steady-State models for optimizing control of steady-state industrial processes which are described by bilinear models uses the step signals of steady-state as input identification signals in the course of optimizing control and obtain the strong consistency estimations of steady-state models. But only under the hypothesis of the Fi is reversible matrix, the identification technique is used. In the paper, the reversibility of Fi is studied and the sufficient conditions for system identifiability are given.
The foundation of Steady-State models for optimizing control of steady-state industrial processes which are described by bilinear models uses the step signals of steady-state as input identification signals in the course of optimizing control and obtain the strong consistency estimations of steady-state models. But only under the hypothesis of the Fi is reversible matrix, the identification technique is used. In the paper, the reversibility of Fi is studied and the sufficient conditions for system identifiability are given.
2005, 34(6): 828-831,864.
Abstract:
Based on collision detection algorithm, a motion planning method for globally solving for the point-to-point inverse kinematics of robotic manipulators with high redundancy is developed. It can capture the connectivity of the connected components of the free configuration space from initial configuration to the objective configuration for the manipulators with constrains due to the joint limits, self-collision and obstacles in the environment. The efficiency and the practical value of the method is illustrated.
Based on collision detection algorithm, a motion planning method for globally solving for the point-to-point inverse kinematics of robotic manipulators with high redundancy is developed. It can capture the connectivity of the connected components of the free configuration space from initial configuration to the objective configuration for the manipulators with constrains due to the joint limits, self-collision and obstacles in the environment. The efficiency and the practical value of the method is illustrated.
2005, 34(6): 832-835.
Abstract:
The circular interpolation is widely used in NC manufacturing of curve contours. Because the Min-error interpolation method for the circular interpolation is complicate and low efficiency, the problem of precision and efficiency about circular interpolation algorithm are discussed in this paper. A revised interpolation algorithm based on Min-error interpolation method is proposed, and the problem of unified programming in four quadrants is discussed. The revised interpolation algorithm has the advantages of simplicity, good path precision and short running time.
The circular interpolation is widely used in NC manufacturing of curve contours. Because the Min-error interpolation method for the circular interpolation is complicate and low efficiency, the problem of precision and efficiency about circular interpolation algorithm are discussed in this paper. A revised interpolation algorithm based on Min-error interpolation method is proposed, and the problem of unified programming in four quadrants is discussed. The revised interpolation algorithm has the advantages of simplicity, good path precision and short running time.
2005, 34(6): 836-838.
Abstract:
High initial permeability MnZn soft magnetic materials were fabricated by Oxide ceramic technology, and get microstructure of high initial permeability MnZn by Scanning Electron Microscope(SEM). Examined the effect of anneal temperature on the microstructure and magnetic properties of MnZn ferrite, And get that the anneal temperature of 960℃ is the best one for high initial permeability MnZn soft magnetic material, and get the initial permeability is about 9 500.
High initial permeability MnZn soft magnetic materials were fabricated by Oxide ceramic technology, and get microstructure of high initial permeability MnZn by Scanning Electron Microscope(SEM). Examined the effect of anneal temperature on the microstructure and magnetic properties of MnZn ferrite, And get that the anneal temperature of 960℃ is the best one for high initial permeability MnZn soft magnetic material, and get the initial permeability is about 9 500.
2005, 34(6): 839-842.
Abstract:
Clinical diagnosis is often supported by different imaging modalities with different information. Image fusion from multiple modalities can utilize the complementary information to make more accurate diagnosis. We present a multi-resolution method based on wavelet translation to fuse images of human brain.Experiment results show that this method is a good and effective method.
Clinical diagnosis is often supported by different imaging modalities with different information. Image fusion from multiple modalities can utilize the complementary information to make more accurate diagnosis. We present a multi-resolution method based on wavelet translation to fuse images of human brain.Experiment results show that this method is a good and effective method.
2005, 34(6): 843-845.
Abstract:
Starting from benzoylhydrazine and isophthaloyl chloride,synthetic method and technology of (1,3-bis (5-phenyl)-1,3,4-oxadiazol-2-yl)benzene are studied in details. The yield of product is 56.1% and the purity is 99.9% by the analysis of HPLC. The affection laws of factors such as solvent and method for purification are discussed. The structure and properties of the material are also tested and its PL peaks are between 400~472 nm with its melting point in the range of 247~248℃.
Starting from benzoylhydrazine and isophthaloyl chloride,synthetic method and technology of (1,3-bis (5-phenyl)-1,3,4-oxadiazol-2-yl)benzene are studied in details. The yield of product is 56.1% and the purity is 99.9% by the analysis of HPLC. The affection laws of factors such as solvent and method for purification are discussed. The structure and properties of the material are also tested and its PL peaks are between 400~472 nm with its melting point in the range of 247~248℃.
2005, 34(6): 846-849.
Abstract:
How to improve quickly the reliability of system and prove to be the minimal instruments in the parallel connection have been a long hotter topics in the research of reliability of system. The same problems from the starting of any state (k1,k2,…,kn) are discussed in this paper. It is has proved that the reliability of system get the most quick improvement from the system state (k1,k2,…,kn) if the same instruments is parallel to the subsystem made up of the parts of the reliability. Meanwhile, the algorithm and example are given.
How to improve quickly the reliability of system and prove to be the minimal instruments in the parallel connection have been a long hotter topics in the research of reliability of system. The same problems from the starting of any state (k1,k2,…,kn) are discussed in this paper. It is has proved that the reliability of system get the most quick improvement from the system state (k1,k2,…,kn) if the same instruments is parallel to the subsystem made up of the parts of the reliability. Meanwhile, the algorithm and example are given.
2005, 34(6): 850-853.
Abstract:
The algorithm and explicit formulae for the elements of the inverse of five-diagonal matrices are presented.The results are obtained by relationships between the elements of the inverse and the elements of special twisted decompositions of it.Operation count of the algorithm have an advantage over that of the standard LU decomposition based on the Gaussian elimination,and some results can also be extended to block five-diagonal matrices.Result obtained improves result in the known corresponding references.
The algorithm and explicit formulae for the elements of the inverse of five-diagonal matrices are presented.The results are obtained by relationships between the elements of the inverse and the elements of special twisted decompositions of it.Operation count of the algorithm have an advantage over that of the standard LU decomposition based on the Gaussian elimination,and some results can also be extended to block five-diagonal matrices.Result obtained improves result in the known corresponding references.
2005, 34(6): 854-856.
Abstract:
Let a (p,q)-additive selfmap f on near-algebra or Banach algebra X satisfy f (e)=e and f (u)=ϕ(u) f (u-1)φ(u) whereϕ:X → X andφ:X → DES(X) be an automorphism and antiautomorphism respectively such that ϕ(u)=uφ(u-1)u for each invertible u of X. Then all of the normal invertibles of X have the common eigenvalue λ=2q/(1+q) if p=q≠-1.
Let a (p,q)-additive selfmap f on near-algebra or Banach algebra X satisfy f (e)=e and f (u)=ϕ(u) f (u-1)φ(u) whereϕ:X → X andφ:X → DES(X) be an automorphism and antiautomorphism respectively such that ϕ(u)=uφ(u-1)u for each invertible u of X. Then all of the normal invertibles of X have the common eigenvalue λ=2q/(1+q) if p=q≠-1.
2005, 34(6): 857-860.
Abstract:
This paper sets up a model to examine how the irrational trading behavior such as overreaction and underreaction, optimism and pessimism significantly affects the short price behavior of financial asset. The comparative analysis of the simulated results indicates that even if the information in financial market is symmetric, the financial asset short-term price behavior is significantly different when a greater proportion of irrational traders exist in the market. The financial asset short-term price is more volatile when the irrational trading behavior is more serious.
This paper sets up a model to examine how the irrational trading behavior such as overreaction and underreaction, optimism and pessimism significantly affects the short price behavior of financial asset. The comparative analysis of the simulated results indicates that even if the information in financial market is symmetric, the financial asset short-term price behavior is significantly different when a greater proportion of irrational traders exist in the market. The financial asset short-term price is more volatile when the irrational trading behavior is more serious.
2005, 34(6): 861-864.
Abstract:
Based on the hypothesis of heterogeneous traders, this paper analyzes the strategic behaviors of informed traders and uninformed traders during the process of call auction, and discusses the impact of indicator price information disclosure and public limit order book on the call auction process. At last we discuss the practical implication and policy suggestion.
Based on the hypothesis of heterogeneous traders, this paper analyzes the strategic behaviors of informed traders and uninformed traders during the process of call auction, and discusses the impact of indicator price information disclosure and public limit order book on the call auction process. At last we discuss the practical implication and policy suggestion.
2005, 34(6): 865-868.
Abstract:
Chinese security funds implement the positive feedback trading strategy to some extent. The higher the herding in the formation period is, the higher the abnormal returns one quarter, half year and one year before the formation period and during the formation period are, vice versa. In the 2000 annual statement, herding is beneficial to stabilizing the stock market. At the same time there is no significant mean-reversion for the abnormal returns before and after the formation period in both 2000 semiannual statement and 2001 semiannual statement. Finally, the herding direction (buy-side herding or sell-side herding) is unrelated to the portfolio abnormal return.
Chinese security funds implement the positive feedback trading strategy to some extent. The higher the herding in the formation period is, the higher the abnormal returns one quarter, half year and one year before the formation period and during the formation period are, vice versa. In the 2000 annual statement, herding is beneficial to stabilizing the stock market. At the same time there is no significant mean-reversion for the abnormal returns before and after the formation period in both 2000 semiannual statement and 2001 semiannual statement. Finally, the herding direction (buy-side herding or sell-side herding) is unrelated to the portfolio abnormal return.
2005, 34(6): 869-872.
Abstract:
The quoted passage of Modern Radar Periodical from 2000 to 2004 is accounted by the analytical method. Eight important indexes for evaluating the publication quality, i.e. total citation rate, impact factor, citation rate by other periodicals, number of reference, average number of quoted passage, the number of coauthor papers, the distribution of authors and the rate of fund-sponsored papers are statistically analyzed, and the statistical results are hereby given:total citation rate of 97.8, avarage impact factor of 0.103, average citation rate by other periodicals of 0.705, average reference numbers of 627.6, average number of quoted passage 4.52, number of coauthor papers 122.2, and the rate of fund-sponsored papers 0.096. The study is aimed to find out the problems occurred in Modern Radar periodical, which is significantly valuable for improving the quality of Modern Radar.
The quoted passage of Modern Radar Periodical from 2000 to 2004 is accounted by the analytical method. Eight important indexes for evaluating the publication quality, i.e. total citation rate, impact factor, citation rate by other periodicals, number of reference, average number of quoted passage, the number of coauthor papers, the distribution of authors and the rate of fund-sponsored papers are statistically analyzed, and the statistical results are hereby given:total citation rate of 97.8, avarage impact factor of 0.103, average citation rate by other periodicals of 0.705, average reference numbers of 627.6, average number of quoted passage 4.52, number of coauthor papers 122.2, and the rate of fund-sponsored papers 0.096. The study is aimed to find out the problems occurred in Modern Radar periodical, which is significantly valuable for improving the quality of Modern Radar.
