ISSN 
2000 Vol. 29, No. 6
2000, 29(6): 569-572.
Abstract:
In this paper, an idea of distributed data management and the application architecture in mobile telecommunication management system are introduced and applied to the mobile telecommunication network management area. Some data structures and arithmetic are suggested in this paper. The performance properties of the architecture are discussed from user's level and a parallel computing hierarchy.
In this paper, an idea of distributed data management and the application architecture in mobile telecommunication management system are introduced and applied to the mobile telecommunication network management area. Some data structures and arithmetic are suggested in this paper. The performance properties of the architecture are discussed from user's level and a parallel computing hierarchy.
2000, 29(6): 578-582.
Abstract:
This paper analyzes the statistics of speckle. Based on Wavelet transform, this paper gives a method for speckle suppression based on multiscale decomposition. The method uses the low frequency part HH in speckle filtering. The results show the effectiveness of the method. This paper also analyzes the performance of different wavelets. According to ENL, the results obtained by using different wavelets are compared. Some beneficial conclusions are given.
This paper analyzes the statistics of speckle. Based on Wavelet transform, this paper gives a method for speckle suppression based on multiscale decomposition. The method uses the low frequency part HH in speckle filtering. The results show the effectiveness of the method. This paper also analyzes the performance of different wavelets. According to ENL, the results obtained by using different wavelets are compared. Some beneficial conclusions are given.
2000, 29(6): 583-586.
Abstract:
This paper proposes a recursive approach to direction of arrival estimation of spatially distributed signals. By using 1-dimensional DOA searching rather than resort to multidimensional parametric searching, DOA estimation of distributed sources are obtained. The algorithm needs little prior knowledge about the distribution function of the sources and can be applied in non-uniform array condition. The simulation shows that the new method outperforms the MUSIC algorithm by reducing the sensitivity for scenarios with distributed sources.
This paper proposes a recursive approach to direction of arrival estimation of spatially distributed signals. By using 1-dimensional DOA searching rather than resort to multidimensional parametric searching, DOA estimation of distributed sources are obtained. The algorithm needs little prior knowledge about the distribution function of the sources and can be applied in non-uniform array condition. The simulation shows that the new method outperforms the MUSIC algorithm by reducing the sensitivity for scenarios with distributed sources.
2000, 29(6): 587-590.
Abstract:
The Montgomery algorithm used in modular exponentiation with very large operand is briefly introduced. A new Montgomery algorithm is presented for modular exponentiation computation with very large operand based on binary redundant representations. Computation of modular exponentiation with very large operand is furthermore speeded up by decreasing recursive steps and carry propagation in modular multiplication.It is shown by theoretical analysis that recursive stops are also decreased by 17.2% on average.
The Montgomery algorithm used in modular exponentiation with very large operand is briefly introduced. A new Montgomery algorithm is presented for modular exponentiation computation with very large operand based on binary redundant representations. Computation of modular exponentiation with very large operand is furthermore speeded up by decreasing recursive steps and carry propagation in modular multiplication.It is shown by theoretical analysis that recursive stops are also decreased by 17.2% on average.
2000, 29(6): 591-594.
Abstract:
In this paper, the recently proposed Turbo-codes are applied to multilevel modulation, then to multistage decoding. Base on the information theory, the method of designing rates and interleaving lengths of Turbo-codes is proposed. Let the lower levels codes have higher correct error capacities, and the higher levels codes have higher transmission capacities, the transmission rate of the system is improved. The performance of Turbo multilevel codes is analyzed, and its formula of error rate is obtained. Simulation results show the validity of the design scheme and the formula.
In this paper, the recently proposed Turbo-codes are applied to multilevel modulation, then to multistage decoding. Base on the information theory, the method of designing rates and interleaving lengths of Turbo-codes is proposed. Let the lower levels codes have higher correct error capacities, and the higher levels codes have higher transmission capacities, the transmission rate of the system is improved. The performance of Turbo multilevel codes is analyzed, and its formula of error rate is obtained. Simulation results show the validity of the design scheme and the formula.
2000, 29(6): 595-599.
Abstract:
Based on visual studio, this paper introduces a solution of PC-to-singlechip serial communication. It provides the modules of communication system in both PC and single chip, which are derived from the OSI network hierarchy module. This paper also provides the analysis of construction, data structure and scheduling of the modules. The hierarchy structure of this solution reflects the logical modularity of the whole system, whereby the system eliminates the reliability on hardware as much as possible. It provides the portability and flexibility to the system. The independence of each I/O driver on different hardware proves the coherence of subsystems.
Based on visual studio, this paper introduces a solution of PC-to-singlechip serial communication. It provides the modules of communication system in both PC and single chip, which are derived from the OSI network hierarchy module. This paper also provides the analysis of construction, data structure and scheduling of the modules. The hierarchy structure of this solution reflects the logical modularity of the whole system, whereby the system eliminates the reliability on hardware as much as possible. It provides the portability and flexibility to the system. The independence of each I/O driver on different hardware proves the coherence of subsystems.
2000, 29(6): 600-603.
Abstract:
In this paper, discrete wavelet multi-tone modulation techniques for Hybrid Fiber/Coax up-stream are studied. The DWMT modulation techniques with discrete multi-tone are compared. It is proved that DWMT is better than DMT through computer simulation expriments.DWMT has a better spectral performance by carefuly desiging of subchannel and thus has a stronger anti-ICI ability than DMT.
In this paper, discrete wavelet multi-tone modulation techniques for Hybrid Fiber/Coax up-stream are studied. The DWMT modulation techniques with discrete multi-tone are compared. It is proved that DWMT is better than DMT through computer simulation expriments.DWMT has a better spectral performance by carefuly desiging of subchannel and thus has a stronger anti-ICI ability than DMT.
2000, 29(6): 604-608.
Abstract:
In this paper, RCS 2D-imaging of rotating targets is analyzed using Kirchhoff integral theorem. It is shown that the imaging section includes the axle from radar stage to rotating stage and the imaging section is vertical to the line connecting two antennas. That is, when the line and the imaging section are coplanar, only a RCS 1D-imaging of rotating targets can be obtained, and when the line is vertical to the imaging section, a RCS 2D-imaging of rotating targets can be gotten. The results obtained in this paper give a theory base for the system design of RCS 2D-imaging of rotating targets.
In this paper, RCS 2D-imaging of rotating targets is analyzed using Kirchhoff integral theorem. It is shown that the imaging section includes the axle from radar stage to rotating stage and the imaging section is vertical to the line connecting two antennas. That is, when the line and the imaging section are coplanar, only a RCS 1D-imaging of rotating targets can be obtained, and when the line is vertical to the imaging section, a RCS 2D-imaging of rotating targets can be gotten. The results obtained in this paper give a theory base for the system design of RCS 2D-imaging of rotating targets.
2000, 29(6): 609-612.
Abstract:
In this paper, etching characteristics of TMAH solutions is introduced. Application of TMAH solutions which is used as etchant in boron etch-stop and anisotropic etching process in the manufacturing of single-crystal and polysilicon pressure sensors is mainly discussed. Satisying process condition and experimental results are obtained through experiments.
In this paper, etching characteristics of TMAH solutions is introduced. Application of TMAH solutions which is used as etchant in boron etch-stop and anisotropic etching process in the manufacturing of single-crystal and polysilicon pressure sensors is mainly discussed. Satisying process condition and experimental results are obtained through experiments.
2000, 29(6): 613-616.
Abstract:
A novel technique is described for the preparation of Al2O3-doped CeO2-coated ZrO2 nanopowders from a solution of aluminium nitrate and cerium nitrate in a mixed alcohol/water suspension with monoclinic zirconia powder. Drying of the suspension and subsequent calcination of the powder at 800℃ results in Al2O3-doped CeO2-coated monoclinic ZrO2 nanopowder with a grain size below 100 nm. That fabricated powder can be pressureless sintered in air at 1 450℃ into dense Ce-TZP materials with an excellent fracture toughness of 11 MPa m1/2 and a Vickers hardness of 750 kg/mm2 (HV30). The microstructure and mechanical properties of the Al2O3-doped CeO2-coated powder based TZP are compared with those of a Ce-TZP obtained from commercially available co-precipitated powder.
A novel technique is described for the preparation of Al2O3-doped CeO2-coated ZrO2 nanopowders from a solution of aluminium nitrate and cerium nitrate in a mixed alcohol/water suspension with monoclinic zirconia powder. Drying of the suspension and subsequent calcination of the powder at 800℃ results in Al2O3-doped CeO2-coated monoclinic ZrO2 nanopowder with a grain size below 100 nm. That fabricated powder can be pressureless sintered in air at 1 450℃ into dense Ce-TZP materials with an excellent fracture toughness of 11 MPa m1/2 and a Vickers hardness of 750 kg/mm2 (HV30). The microstructure and mechanical properties of the Al2O3-doped CeO2-coated powder based TZP are compared with those of a Ce-TZP obtained from commercially available co-precipitated powder.
2000, 29(6): 617-620.
Abstract:
In this paper, a dynamic error measuring system, which is a newly integrated setup based on PSD is analyzed and built. Its measuring principle and linear model are deduced. It can be used to measure and control spatial error for one or many beam robot. Corresponding dynamic error model is analyzed and deduced, then the reduced and linear model used for plane robot is obtained.
In this paper, a dynamic error measuring system, which is a newly integrated setup based on PSD is analyzed and built. Its measuring principle and linear model are deduced. It can be used to measure and control spatial error for one or many beam robot. Corresponding dynamic error model is analyzed and deduced, then the reduced and linear model used for plane robot is obtained.
2000, 29(6): 621-624.
Abstract:
Based on the satisfactory solution principle(SSP), this paper analyzes the contradictory relation and studies the approximate relation of PID control system. Through the approximate relation, the eclectic principle applied in the optimization of PID control scheme is decided. An example is proposed to testify the correctness and rationality of the optimization of PID control scheme based on eclectic principle. Some characters and applicable range of this optimize means are also discussed.
Based on the satisfactory solution principle(SSP), this paper analyzes the contradictory relation and studies the approximate relation of PID control system. Through the approximate relation, the eclectic principle applied in the optimization of PID control scheme is decided. An example is proposed to testify the correctness and rationality of the optimization of PID control scheme based on eclectic principle. Some characters and applicable range of this optimize means are also discussed.
2000, 29(6): 625-628.
Abstract:
In this paper, a QoS scheme is given to support applications with QoS requirements under resource constraint in open system. Specifically, a series of abstract structure, describing characteristics of end-to-end applications and system resources, as well as algorithms supporting the realization of QoS, are designed in this paper. The scheme addresses common problems found in open systems supporting QoS guarantees, such as lack of harmony QoS expressiveness, ect. In order to let as many as possible applications get system service at the same time, the scheme also supports QoS dynamic degradation.
In this paper, a QoS scheme is given to support applications with QoS requirements under resource constraint in open system. Specifically, a series of abstract structure, describing characteristics of end-to-end applications and system resources, as well as algorithms supporting the realization of QoS, are designed in this paper. The scheme addresses common problems found in open systems supporting QoS guarantees, such as lack of harmony QoS expressiveness, ect. In order to let as many as possible applications get system service at the same time, the scheme also supports QoS dynamic degradation.
2000, 29(6): 629-631.
Abstract:
In this paper, the method of designing a virtual device driver to receive RARP requests and send RARP responses is discussed. To manage the configure information, a database in PostgreSQL DBMS is established. Information can be obtained by query procedure and delivered to virtual device driver.
In this paper, the method of designing a virtual device driver to receive RARP requests and send RARP responses is discussed. To manage the configure information, a database in PostgreSQL DBMS is established. Information can be obtained by query procedure and delivered to virtual device driver.
2000, 29(6): 632-635.
Abstract:
This paper proposes the architecture and protocols supporting the Internet integrated services in Windows2000, which provide multimedia application and real-time application such as teleconferencing, remote seminars, and video on demand. A video conference based on Windows2000 QoS technology is presented. The parameters of every kind of medium stream in the video conference are analyzed in detail.
This paper proposes the architecture and protocols supporting the Internet integrated services in Windows2000, which provide multimedia application and real-time application such as teleconferencing, remote seminars, and video on demand. A video conference based on Windows2000 QoS technology is presented. The parameters of every kind of medium stream in the video conference are analyzed in detail.
2000, 29(6): 636-639.
Abstract:
In this paper, the concept and syntax of visual programming language are described, and an icon authoring language of MPAT is introduced. MPAT consists of structural presentation flow editor which is controlled by iconic programming language syntax, presentation context workshop, and interpreter. The design and implement of MPAT are investigated in detail.
In this paper, the concept and syntax of visual programming language are described, and an icon authoring language of MPAT is introduced. MPAT consists of structural presentation flow editor which is controlled by iconic programming language syntax, presentation context workshop, and interpreter. The design and implement of MPAT are investigated in detail.
2000, 29(6): 640-646.
Abstract:
The key to applying price leadership model is that dominant firm can determine its demand function. In this paper, a method for dominant firm to accurately determine its demand function is presented based on the market demand function and cost function of leading firm and following firms. The related calculation formula are given. The conclusion presented in this paper is also tested and verified by two examples. Finally,the relationship between dominant firm's demand curve and market demand curve is analyzed.
The key to applying price leadership model is that dominant firm can determine its demand function. In this paper, a method for dominant firm to accurately determine its demand function is presented based on the market demand function and cost function of leading firm and following firms. The related calculation formula are given. The conclusion presented in this paper is also tested and verified by two examples. Finally,the relationship between dominant firm's demand curve and market demand curve is analyzed.
2000, 29(6): 647-650.
Abstract:
This paper uses the moving average trading rule of the technical analysis method to do predictability research. The empirical evidence shows that the technical rules have predictive power, because adopting the moving average trading strategy can produce higher average return than using buy-holding strategy. The results prove theoretically that China's stock market is weak form efficient.
This paper uses the moving average trading rule of the technical analysis method to do predictability research. The empirical evidence shows that the technical rules have predictive power, because adopting the moving average trading strategy can produce higher average return than using buy-holding strategy. The results prove theoretically that China's stock market is weak form efficient.
2000, 29(6): 651-654.
Abstract:
On the basis of the research of real options, the shortcoming of the net present value(NPV) approach-one of the traditional approaches of investment decision-is pointed out in this paper. It is also found that NPV may undervalue the research and development(R&D) project. The discrete-time model, the continuous-time model and the two-period model of an R&D project investment decision are gotten. An example of investment decision of R&D is given.
On the basis of the research of real options, the shortcoming of the net present value(NPV) approach-one of the traditional approaches of investment decision-is pointed out in this paper. It is also found that NPV may undervalue the research and development(R&D) project. The discrete-time model, the continuous-time model and the two-period model of an R&D project investment decision are gotten. An example of investment decision of R&D is given.
2000, 29(6): 655-657.
Abstract:
In this paper, the problem of BIBO stabilization for nonlinear systems of uncertain parameters with time-delay is discussed. Based on the variation of parameters, Liapunov function and the inequality analysis, the sufficient conditions of BIBO stabilization for nonlinear systems of uncertain parameters with time-delay are obtained. The exponential stability and the asymptotic stability for such systems are also given. The conditions are obtained by extending the results of some related references.
In this paper, the problem of BIBO stabilization for nonlinear systems of uncertain parameters with time-delay is discussed. Based on the variation of parameters, Liapunov function and the inequality analysis, the sufficient conditions of BIBO stabilization for nonlinear systems of uncertain parameters with time-delay are obtained. The exponential stability and the asymptotic stability for such systems are also given. The conditions are obtained by extending the results of some related references.
2000, 29(6): 658-661.
Abstract:
In this paper, the moment complete convergence for martingale random variables is discussed. Under certain moment condition, the moment complete convergence for B-valued martinagale random variables is obtained, and the result of Chow about the moment complete convergence for B-valued martingale random variables is generalized. The moment complete convergence for Martingale random variables is studied. Satisfactory results are obtained.
In this paper, the moment complete convergence for martingale random variables is discussed. Under certain moment condition, the moment complete convergence for B-valued martinagale random variables is obtained, and the result of Chow about the moment complete convergence for B-valued martingale random variables is generalized. The moment complete convergence for Martingale random variables is studied. Satisfactory results are obtained.
2000, 29(6): 662-665.
Abstract:
In this paper, a max-min problem with inequality and equality constraints is studied and made into nonlinear optimization problem with inequality and equality. Gradient projcet method is also given. The algorithms get optimization point in infinite steps or get a series of points, whose limit points are optimization points. The algorithms save lots of calculating time and overcome some difficulties in computation, whose convergence are also proved.
In this paper, a max-min problem with inequality and equality constraints is studied and made into nonlinear optimization problem with inequality and equality. Gradient projcet method is also given. The algorithms get optimization point in infinite steps or get a series of points, whose limit points are optimization points. The algorithms save lots of calculating time and overcome some difficulties in computation, whose convergence are also proved.
2000, 29(6): 666-668.
Abstract:
The idea of Fuzzy mathematics is applied to discrete mathematics. According to the relationship between reachability matrix and adjacency matrix, a new formula is testified, which is used for calculating reachability matrix. At the same time, the algorithm of successive square is proposed.
The idea of Fuzzy mathematics is applied to discrete mathematics. According to the relationship between reachability matrix and adjacency matrix, a new formula is testified, which is used for calculating reachability matrix. At the same time, the algorithm of successive square is proposed.
2000, 29(6): 669-672.
Abstract:
Highly conducting polyaniline film is obtained by controlled-potential electrolyze at 0.5~0.6 V (vs.SCE) with Ni electrode (2.0 cm×3.0 cm). Doping agent, aniline concentrations, PH, electrolytic voltage are studied in detail. The best doping agent is HClO4, and the electrolytic system is CH3CN, HClO4, H2O system. Mechanism of electrochromic reaction is investigated by cyclic voltammetry at -0.2~0.8 V. The electrochromic region is yellow-green-blue and the conductivity of the film is 10-1s·cm-1.
Highly conducting polyaniline film is obtained by controlled-potential electrolyze at 0.5~0.6 V (vs.SCE) with Ni electrode (2.0 cm×3.0 cm). Doping agent, aniline concentrations, PH, electrolytic voltage are studied in detail. The best doping agent is HClO4, and the electrolytic system is CH3CN, HClO4, H2O system. Mechanism of electrochromic reaction is investigated by cyclic voltammetry at -0.2~0.8 V. The electrochromic region is yellow-green-blue and the conductivity of the film is 10-1s·cm-1.
