Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of qua...Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control.展开更多
A fast encoding algorithm based on the mean square error （MSE） distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform （WT） coefficients of images, can...A fast encoding algorithm based on the mean square error （MSE） distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform （WT） coefficients of images, can simplify the realization of the non-linear interpolated vector quantization （NLIVQ） technique and make the partial distance search （PDS） algorithm more efficient. Utilizing the relationship of vector L2-norm and its Euclidean distance, some conditions of eliminating unnecessary codewords are obtained. Further, using inequality constructed by the subvector L2-norm, more unnecessary codewords are eliminated. During the search process for code, mostly unlikely codewords can be rejected by the proposed algorithm combined with the non-linear interpolated vector quantization technique and the partial distance search technique. The experimental results show that the reduction of computation is outstanding in the encoding time and complexity against the full search method.展开更多
Spurious signals in direct digital frequency synthesizers （DDFSs） are partly caused by amplitude quantization and phase truncation, which affect their application to many wireless telecommunication systems. These si...Spurious signals in direct digital frequency synthesizers （DDFSs） are partly caused by amplitude quantization and phase truncation, which affect their application to many wireless telecommunication systems. These signals are deterministic and periodic in the time domain, so they appear as line spectra in the frequency domain. Two types of spurious signals due to amplitude quantization are exactly formulated and compared in the time and frequency domains respectively. Then the frequency spectra and power levels of the spurious signals due to amplitude quantization in the absence of phase-accumulator truncation are emphatically analyzed, and the effects of the DDFS parameter variations on the spurious signals are thoroughly studied by computer simulation. And several important conclusions are derived which can provide theoretical support for parameter choice and spurious performance evaluation in the application of DDFSs.展开更多
In this paper, a new amplitude quantization synthesis method for ultralow sidelobe phased arrays is proposed, which is based on the constrained nonlinear optimization algorithm. By introducing a set of critical constr...In this paper, a new amplitude quantization synthesis method for ultralow sidelobe phased arrays is proposed, which is based on the constrained nonlinear optimization algorithm. By introducing a set of critical constraint conditions into the optimization model, we can directly quantize the amplitude distribution instead of replacing it with a continuous equivalent aperture antenna. The mutual coupling and the element patterns are also considered in the quantization synthesis. Finally, some array simulation results are given to show the effectiveness of the method.展开更多
In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is signif...In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is significantly removed and coded with fuzzy vector quantization. The experimental result shows that the method can not only achieve high compression ratio but also remove noise dramatically.展开更多
Currently, 1 bit or 2 bit signal quantization is widely used in satellite navigation software receivers. The bit-wise parallel algorithm has been proposed for 1 bit and 2 bit signal quantization, which performs correl...Currently, 1 bit or 2 bit signal quantization is widely used in satellite navigation software receivers. The bit-wise parallel algorithm has been proposed for 1 bit and 2 bit signal quantization, which performs correlation with high efficiency. In order to improve the performance of the correlator, this paper proposes a new 1.5 bit quantization method. Theoretical analyses are made from the aspects of complexity and quantization loss, and performance comparison between 1.5 bit quantization correlator and traditional correlators is discussed. The results show that the 1.5 bit quantization algorithm can save about 30 percent complexity under similar quantization loss, reduce more than 0.5 dB signal noise ratio（SNR） loss under similar complexity. It shows great performance improvement for correlators of satellite navigation software receivers.展开更多
A novel multi level image segmentation methodology is been proposed with the aim of extracting the salient object,keeping in view,only a small part of the visual scene undergoes attention and reaches the level of awar...A novel multi level image segmentation methodology is been proposed with the aim of extracting the salient object,keeping in view,only a small part of the visual scene undergoes attention and reaches the level of awareness while rest of details are futile.Taking advantage of multilevel gray scale quantization,image prominent object is separated from background,keeping in view the fact;salient object is having high contrast as compared to the background.The inutile fragments were removed using morphological operations of opening and closing and making the image smoothened with Gaussian filter.The optimum threshold is selected for the binary conversion and final extrication of the salient object from the image.The experimental data indicates that hybrid approach leads to improved segmentation with the apparent assertion of prime object extraction.展开更多
Quantized control systems design is motivated by the convergence of controls and communications to address modern engineering applications involving the use of information technology. This paper presents an overview o...Quantized control systems design is motivated by the convergence of controls and communications to address modern engineering applications involving the use of information technology. This paper presents an overview of recent developments on the control of linear and nonlinear systems when the control input is subject to quantization or the quantized states or outputs are used as feedback measurements. The co-existence of high-dimeasionality, quantization, nonlinearity and uncertainty poses great challenges to quantized control of nonlinear systems and thus calls for new ideas and techniques. The field of quantized nonlinear control is still at its infancy. Preliminary results in our recent work based on input-to-state stability and cyclic-small-gain theorems are reviewed. The open problems in quantized nonlinear control are also outlined.展开更多
The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a no...The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a novel networked control system model is described. This model includes many networkinduced features, such as multi-rate sampled-data, quantized signal, time-varying delay and packet dropout. By constructing suitable Lyapunov-Krasovskii functional, a less conservative stabilization criterion is established in terms of linear matrix inequalities. The quantized control strategy involves the updating values of the quantizer parameters μi（i = 1, 2）（μi take on countable sets of values which dependent on the information of the system measurement outputs and the control inputs）. Furthermore, a numerical example is given to illustrate the effectiveness of the proposed method.展开更多
A rule of how the ignition probability or invalidation probability of infantry grenade varies with the projectile quantity is presented based on the statistical analysis. The statistical induction, quantizing analysis...A rule of how the ignition probability or invalidation probability of infantry grenade varies with the projectile quantity is presented based on the statistical analysis. The statistical induction, quantizing analysis and data processing in the infantry grenade type approval test are completed, and we obtain how various test factors in the research item affect the test results(invalidation probability), i.e., quantized data. The acquisition of these quantized data provides theory basis and data auspice for further reasonable filtration of all test factors and the optimization of test scheme.展开更多
文摘Formal state space models of quantum control systems are deduced and a scheme to establish formal state space models via quantization could been obtained for quantum control systems is proposed. State evolution of quantum control systems must accord with Schrdinger equations, so it is foremost to obtain Hamiltonian operators of systems. There are corresponding relations between operators of quantum systems and corresponding physical quantities of classical systems, such as momentum, energy and Hamiltonian, so Schrdinger equation models of corresponding quantum control systems via quantization could been obtained from classical control systems, and then establish formal state space models through the suitable transformation from Schrdinger equations for these quantum control systems. This method provides a new kind of path for modeling in quantum control.
基金the National Natural Science Foundation of China (60602057)the NaturalScience Foundation of Chongqing Science and Technology Commission (2006BB2373).
文摘A fast encoding algorithm based on the mean square error （MSE） distortion for vector quantization is introduced. The vector, which is effectively constructed with wavelet transform （WT） coefficients of images, can simplify the realization of the non-linear interpolated vector quantization （NLIVQ） technique and make the partial distance search （PDS） algorithm more efficient. Utilizing the relationship of vector L2-norm and its Euclidean distance, some conditions of eliminating unnecessary codewords are obtained. Further, using inequality constructed by the subvector L2-norm, more unnecessary codewords are eliminated. During the search process for code, mostly unlikely codewords can be rejected by the proposed algorithm combined with the non-linear interpolated vector quantization technique and the partial distance search technique. The experimental results show that the reduction of computation is outstanding in the encoding time and complexity against the full search method.
基金supported by the National Grand Fundamental Research 973 Program of China(2004CB318109)the National High Technology Research and Development Program of China(863 Program)(2006AA01Z452).
文摘Spurious signals in direct digital frequency synthesizers （DDFSs） are partly caused by amplitude quantization and phase truncation, which affect their application to many wireless telecommunication systems. These signals are deterministic and periodic in the time domain, so they appear as line spectra in the frequency domain. Two types of spurious signals due to amplitude quantization are exactly formulated and compared in the time and frequency domains respectively. Then the frequency spectra and power levels of the spurious signals due to amplitude quantization in the absence of phase-accumulator truncation are emphatically analyzed, and the effects of the DDFS parameter variations on the spurious signals are thoroughly studied by computer simulation. And several important conclusions are derived which can provide theoretical support for parameter choice and spurious performance evaluation in the application of DDFSs.
文摘In this paper, a new amplitude quantization synthesis method for ultralow sidelobe phased arrays is proposed, which is based on the constrained nonlinear optimization algorithm. By introducing a set of critical constraint conditions into the optimization model, we can directly quantize the amplitude distribution instead of replacing it with a continuous equivalent aperture antenna. The mutual coupling and the element patterns are also considered in the quantization synthesis. Finally, some array simulation results are given to show the effectiveness of the method.
文摘In this paper a novel coding method based on fuzzy vector quantization for noised image with Gaussian white-noise pollution is presented. By restraining the high frequency subbands of wavelet image the noise is significantly removed and coded with fuzzy vector quantization. The experimental result shows that the method can not only achieve high compression ratio but also remove noise dramatically.
基金supported by the National Natural Science Foundation of China(61101076413741376147017)
文摘Currently, 1 bit or 2 bit signal quantization is widely used in satellite navigation software receivers. The bit-wise parallel algorithm has been proposed for 1 bit and 2 bit signal quantization, which performs correlation with high efficiency. In order to improve the performance of the correlator, this paper proposes a new 1.5 bit quantization method. Theoretical analyses are made from the aspects of complexity and quantization loss, and performance comparison between 1.5 bit quantization correlator and traditional correlators is discussed. The results show that the 1.5 bit quantization algorithm can save about 30 percent complexity under similar quantization loss, reduce more than 0.5 dB signal noise ratio（SNR） loss under similar complexity. It shows great performance improvement for correlators of satellite navigation software receivers.
文摘A novel multi level image segmentation methodology is been proposed with the aim of extracting the salient object,keeping in view,only a small part of the visual scene undergoes attention and reaches the level of awareness while rest of details are futile.Taking advantage of multilevel gray scale quantization,image prominent object is separated from background,keeping in view the fact;salient object is having high contrast as compared to the background.The inutile fragments were removed using morphological operations of opening and closing and making the image smoothened with Gaussian filter.The optimum threshold is selected for the binary conversion and final extrication of the salient object from the image.The experimental data indicates that hybrid approach leads to improved segmentation with the apparent assertion of prime object extraction.
基金Supported by National Science Foundation of USA （DMS-0906659. ECCS-1230040）
文摘Quantized control systems design is motivated by the convergence of controls and communications to address modern engineering applications involving the use of information technology. This paper presents an overview of recent developments on the control of linear and nonlinear systems when the control input is subject to quantization or the quantized states or outputs are used as feedback measurements. The co-existence of high-dimeasionality, quantization, nonlinearity and uncertainty poses great challenges to quantized control of nonlinear systems and thus calls for new ideas and techniques. The field of quantized nonlinear control is still at its infancy. Preliminary results in our recent work based on input-to-state stability and cyclic-small-gain theorems are reviewed. The open problems in quantized nonlinear control are also outlined.
基金supported by the National Natural Science Foundation of China (60574011)College Research Project of Liaoning Province(L2010522)
文摘The problem of the quantized dynamic output feedback controller design for networked control systems is mainly discussed. By using the quantized information of the system measurement output and the control input, a novel networked control system model is described. This model includes many networkinduced features, such as multi-rate sampled-data, quantized signal, time-varying delay and packet dropout. By constructing suitable Lyapunov-Krasovskii functional, a less conservative stabilization criterion is established in terms of linear matrix inequalities. The quantized control strategy involves the updating values of the quantizer parameters μi（i = 1, 2）（μi take on countable sets of values which dependent on the information of the system measurement outputs and the control inputs）. Furthermore, a numerical example is given to illustrate the effectiveness of the proposed method.
基金Supported by National Natural Science Foundation of China （60674021）, Program for New Century Excellent Talents in University （NCET-04-0283）, the Funds for Creative Research Groups of China （60521003）, Program for Changjiang Scholars and Innovative Research Team in University （IRT0421）, the State Key Program of National Natural Science of China （60534010） and the Funds of Ph. D. Program of Ministry of Education, China （20060145019）
文摘使量子化的动态产量反馈 H 控制为的问题分离时间线性时间不变(LTI ) 系统在这份报纸被调查。考虑的 quantizer 动态、镇静一可调节激增参数和静态的 quantizer。静态的 quantizer 范围具有实际意义并且充分被考虑。首先，考虑量子化错误，使量子化的控制策略控制器状态依赖于不仅而且在系统测量产量上，它被建议以便使量子化的靠近环的系统是 asymptotically 稳定的，与规定 H，性能跳。根据这结果，然后，一个反复的基于 LMI 的优化算法被开发优化静态的 quantizer 范围为靠近环的系统满足 H 表演要求。一个例子被举说明建议方法的有效性。
文摘A rule of how the ignition probability or invalidation probability of infantry grenade varies with the projectile quantity is presented based on the statistical analysis. The statistical induction, quantizing analysis and data processing in the infantry grenade type approval test are completed, and we obtain how various test factors in the research item affect the test results(invalidation probability), i.e., quantized data. The acquisition of these quantized data provides theory basis and data auspice for further reasonable filtration of all test factors and the optimization of test scheme.
