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Han Zheng-zhi

Bio: Han Zheng-zhi is an academic researcher from Shanghai Jiao Tong University. The author has contributed to research in topics: Control-Lyapunov function & Lyapunov redesign. The author has an hindex of 4, co-authored 21 publications receiving 57 citations.

Papers
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Proceedings ArticleDOI
07 Nov 2002
TL;DR: With the introduction of the constrained relative degree, an SILC algorithm combined with a feedback control law is proposed for singular systems and convergence is guaranteed not only at the sampling instants but on the entire operation interval, thus the inter-sample behavior guaranteed, which is more practical for real implementation.
Abstract: Sampled-data iterative learning control (SILC) for singular systems is addressed for the first time. With the introduction of the constrained relative degree, an SILC algorithm combined with a feedback control law is proposed for singular systems. Convergence of the algorithm is proved in sup-norm, while the conventional convergence analysis is in /spl lambda/-norm. The final tracking error uniformly converges to a small residual set whose level of magnitude depends on the system dynamics and the sampling-period. Inequalities to estimate the level the existing results of SILC, convergence is guaranteed not only at the sampling instants but on the entire operation interval, thus the inter-sample behavior guaranteed, which is more practical for real implementation.

9 citations

Journal Article
TL;DR: The chaotic image encryption technique was presented; some advantages with chaotic technique were illustrated and some valuable problems were pointed out for further research.
Abstract: In this paper, the authors summarized the latest development of the image encryption techniques Some techniques such as (1) matrix transform/pixel permutation based, (2) pseudo-random sequences based, (3) SCAN language based, (4) "secret key image" based, (5) SCAN language with quadtree coding based, and (6) commercial cryptography with vector quantization coding based image encryption techniques were illustrated Advantages and disadvantages of these algorithms were compared and the suitability was discussed respectively Particularly, the chaotic image encryption technique was presented; some advantages with chaotic technique were illustrated and some valuable problems were pointed out for further research

6 citations

Journal Article
TL;DR: An improved chaotic optimization algorithm is proposed by combining GA, chaotic optimization and mutative scale method, which can overcome premature convergence of GA and improve search speed.
Abstract: To overcome premature convergence of genetic algorithm(GA) and long search time of chaotic optimization,an improved chaotic optimization algorithm(ICOA) is proposed by combining GA,chaotic optimization and mutative scale method.This algorithm uses chaotic characteristics-randomness,ergodicity and regularity to avoid trapping around local optima.It can overcome premature convergence of GA.At the same time,mutative scale method is introduced into the algorithm to improve search speed.The convergence analysis of algorithm is also given.Finally,the proposed algorithm is applied to solve some complex benchmark functions,and the simulations show the proposed algorithm can provide better performance than mutative scale chaotic algorithm and GA.

6 citations

Journal Article
TL;DR: The history and current research of iterative learning control (ILC) are reviewed, including learning algorithms and analysis techniques, connection between ILC and other control paradigms, and applications as mentioned in this paper.
Abstract: The history and current research of iterative learning control (ILC) are reviewed, including learning algorithms and analysis techniques, connection between ILC and other control paradigms, and applications. Several major advanced problems are presented such as frequency-domain based ILC, 2-D theory based ILC, and Lyapunov direct method based ILC, optimization based ILC, sampled-data ILC. Existing problems and future research directions are also discussed.

6 citations

Journal Article
TL;DR: This paper presents a new definition, called dynamic right factorization, for nonlinear dynamic control systems, that takes the initial conditions as well as the system input into account.
Abstract: −− The output behavior of a nonlinear control system depends not only on its input but also on its initial conditions. These two factors have to be considered simultaneously in nonlinear systems design. This paper presents a new definition, called dynamic right factorization, for nonlinear dynamic control systems. This factorization takes the initial conditions as well as the system input into account. Coprimeness and fundamental properties of dynamic right coprime factorization are investigated. Its relations to the system observability and the observer design problem are discussed. An example is given to illustrate the procedure of obtaining the dynamic right factorization and designing an observer for a given nonlinear dynamic system.

4 citations


Cited by
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Journal ArticleDOI
01 Nov 2007
TL;DR: The iterative learning control (ILC) literature published between 1998 and 2004 is categorized and discussed, extending the earlier reviews presented by two of the authors.
Abstract: In this paper, the iterative learning control (ILC) literature published between 1998 and 2004 is categorized and discussed, extending the earlier reviews presented by two of the authors. The papers includes a general introduction to ILC and a technical description of the methodology. The selected results are reviewed, and the ILC literature is categorized into subcategories within the broader division of application-focused and theory-focused results.

1,417 citations

Journal ArticleDOI
TL;DR: This paper gathers the current mainstream quantum image representations (QIRs) and discusses the advances made in the area and believes this compendium will provide the readership an overview of progress witnessed while also simulating further interest to pursue more advanced research in it.
Abstract: Quantum image processing (QIMP) is devoted to utilizing the quantum computing technologies to capture, manipulate, and recover quantum images in different formats and for different purposes. Logically, percolating this requires that representations to encode images based on the quantum mechanical composition of any potential quantum computing hardware be conjured. This paper gathers the current mainstream quantum image representations (QIRs) and discusses the advances made in the area. Some similarities, differences, and likely applications for some of the available QIRs are reviewed. We believe this compendium will provide the readership an overview of progress witnessed in the area of QIMP while also simulating further interest to pursue more advanced research in it.

246 citations

Journal ArticleDOI
TL;DR: A survey on iterative learning control with incomplete information and associated control system design is conducted, expected to improve understanding of the restrictive relationship and trade-off between incomplete data and tracking performance, quantitatively, and promote further developments of ILC theory.
Abstract: This paper conducts a survey on iterative learning control ( ILC ) with incomplete information and associated control system design, which is a frontier of the ILC field. The incomplete information, including passive and active types, can cause data loss or fragment due to various factors. Passive incomplete information refers to incomplete data and information caused by practical system limitations during data collection, storage, transmission, and processing, such as data dropouts, delays, disordering, and limited transmission bandwidth. Active incomplete information refers to incomplete data and information caused by man-made reduction of data quantity and quality on the premise that the given objective is satisfied, such as sampling and quantization. This survey emphasizes two aspects: the first one is how to guarantee good learning performance and tracking performance with passive incomplete data, and the second is how to balance the control performance index and data demand by active means. The promising research directions along this topic are also addressed, where data robustness is highly emphasized. This survey is expected to improve understanding of the restrictive relationship and trade-off between incomplete data and tracking performance, quantitatively, and promote further developments of ILC theory.

108 citations

Journal ArticleDOI
01 Sep 2007
TL;DR: To prevent this kind of attack, a full inter-block shuffle (FIBS) approach is proposed and can be employed to improve the encryption security in all DCT-based algorithms, such as JPEG, MPEG video and H.26x video.
Abstract: Focusing on the encryption of digital image and video, an intrinsic weakness of all existing discrete-cosine-transform (DCT) based algorithms is reported. This serious weakness of DCT-based encryptions is analysed theoretically and then demonstrated practically. As an instance, a novel attack algorithm is proposed to acquire the sketch information from encrypted data without any prior knowledge of the encryption algorithm. The quality of the extracted sketch is then evaluated by comparing with the original picture edge. Thereafter, to prevent this kind of attack, a full inter-block shuffle (FIBS) approach is proposed. This method can be employed to improve the encryption security in all DCT-based algorithms, such as JPEG, MPEG video and H.26x video.

50 citations

Journal ArticleDOI
TL;DR: A robust nonlinear control technology is presented for an aluminum plate thermal process with the Peltier device by using operator-based robust right coprime factorization approach in this paper.
Abstract: Recently, Peltier device has attracted much attention in cooling process industry. Peltier device is a kind of device with thermoelectric effect which contains three effects such as Peltier effect, Seebeck effect and Thomson effect1, 2. It can be used to cool or heat by Peltier effect and generate electric power by Seebeck effect. Thomson effect relates the rate of generation of reversible heat inside a homogeneous conductor with a temperature gradient23. Due to the Peltier effect, one side of Peltier device is endothermic and another side is radiation when an electric current is applied to it, and the hot side and cold side reverse when opposite current is applied22, 23. Because heating can be achieved more easily and economically by many other methods, Peltier devices are mostly used for cooling. Peltier cooler uses the Peltier effect to create a temperature difference between the two sides of the device. So, it is an interesting consequence that the Peltier effect is used to make a cooler. Due to compact size, not generating vibration noises and freon gas, the Peltier devices are widely used in many applications3, 4, 23. For example in the past years refrigerators used fluorocarbon generally. However, such refrigerators are prohibited gradually because it leads the disruption of ozone layers and affects the climatic change. So the Peltier effect is considered to create the refrigerator. Peltier devices are also commonly used in camping and portable coolers and for cooling electronic components and small instruments22. Peltier coolers can be used to cool computer components to keep temperatures within design limits without the noise of a fan, or to maintain stable functioning when overclocking23. Moreover, there are still some application products including some small wine coolers, some icing devices for medical treatment and so on. In this paper, we focus on the control aspects of a Peltier-based aluminum plate thermal process. Linear PID controllers or switching PID controllers are commonly used in Peltier-based thermal process due to their simplicity in both design and implementation24, 25. However, Peltier cooling performance is a function of ambient temperature, hot and cold side heat exchanger (heat sink) performance, thermal load, Peltier module geometry and Peltier electrical parameters24. Therefore, in general, the Peltier actuated process is a nonlinear control affine system. The output temperature depends not only on the current, but also on square of the current. For the complex nonlinear, it is difficult to achieve high control accuracy (±0.2°C) by using the mentioned PID controller designs, which is required in some applications such as laser frequency elements. Conventional nonlinear controller design techniques cannot also be applied since the dynamics model does not belong to the typical nonlinear control affine form3, 25. To resolve this problem, a robust nonlinear control technology is presented for an aluminum plate thermal process with the Peltier device by using operator-based robust right coprime factorization approach in this paper. Operator theory is an advanced control theory based on an idea that a signal in the input space is mapped to the output space and some researches in regards to the theory have been conducted5, 6, 11, 12. The relationship between the robustness of the right coprime factorization and the robust stability of the perturbed nonlinear system is shown by Chen and Han7, 14. Based on the design scheme a robust tracking control system is proposed by Deng et al. 10, 13, 18 and the perturbed signal does not affect the system output. So, the operatorbased control method can be applied to a broader class of nonlinear systems with perturbations. Furthermore, a method to control unstable systems with input constraints is given in ref 15, 17, 19 where the controlled system with the input constraints satisfies robust right coprime factorization. The advantage of the operatorbased control is that the control design is relatively simple because bounded input and bounded output stability is guaranteed21, 26. Based on the operator theory, nonlinear controller for the aluminum plate thermal process with Peltier device is designed by using robust right coprime factorization concept. That is, to ensure the robust stability, robust controller is considered and operator-based tracking filter is also designed to obtain the desired output tracking performance. As a result the designed control system is to ensure the robust stability and pursue the perfect output tracking performance. The effectiveness of the designed system is shown by the simulation and experiment. The contents of this paper are written as follows. Firstly, system architecture and function for Peltier actuated process is given. Then modelling of the thermal process is shown. Next, an operator-based robust stabilization controller is designed by robust right coprime factorization method. Meanwhile an operator-based tracking control is considered to satisfy tracking performance. Further, simulation and experimental results are given to confirm the proposed method. Finally we draw the conclusion on our current and show future work.

43 citations