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Tissue P systems with cell separation: attacking the partition problem

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Science China(Information Sciences) 2011年第2期54卷 293-304页

作者： ZHANG XingYi1, WANG Shuo2, NIU YunYun2 & PAN LinQiang2 1key lab of intelligent Computing and Signal Processing of Ministry of Education, School of Computer Science and technology, Anhui University, Hefei 230039, China 2Image Processing and intelligent Control key laboratory of Education Ministry of China, Department of Control Science and Engineering, Huazhong University of Science and technology, Wuhan 430074, China 1. key lab of intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and Technology Anhui University Hefei 230039 China2. Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Tissue P systems are distributed parallel and non-deterministic computing models in the framework of membrane computing, which are inspired by intercellular communication and cooperation between neurons. Recently, cell separation is introduced into tissue P systems, which enables systems to generate an exponential workspace in a polynomial time. In this work, the computational power of tissue P systems with cell separation is investigated. Specifically, a uniform family of tissue P systems with cell separation is constructed for effciently solving a well-known NP-complete problem, the partition problem.

关键词： membrane computing tissue P system cell separation partition problem

SAR image despeckling based on edge detection and nonsubsampled second generation bandelets

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Journal of systems Engineering and Electronics 2009年第3期20卷 519-526页

作者： Zhang Wenge~(1,2),Liu Fang~(1,2),Jiao Licheng~(2,3)& Gao Xinbo~(2,3) 1.School of Computer Science and technology,Xidian Univ.,Xi’an 710071,P.R.China 2.key lab.of intelligent Perception and Image Understanding of Ministry of Education of China,Xi’an 710071,P.R.China 3.Inst,of intelligent Information Processing,Xidian Univ.,Xi’an 710071,P.R.China School of Computer Science and technology Xidian Univ. Xi'an 710071 P. R. China key lab. of intelligent Perception and Image Understanding of Ministry of Education of China Xi'an 710071 P. R. China key lab. of intelligent Perception and Image Understanding of Ministry of Education of China Xi'an 710071 P. R. China Inst. of intelligent Information Processing Xidian Univ. Xi'an 710071 P. R. China

To preserve the sharp features and details of the synthetic aperture radar （SAR） image effectively when despeckling, a despeckling algorithm with edge detection in nonsubsampled second generation bandelet transform （NSBT） domain is proposed. First, the Canny operator is utilized to detect and remove edges from the SAR image. Then the NSBT which has an optimal approximation to the edges of images and a hard thresholding rule are used to approximate the details while despeckling the edge-removed image. Finally, the removed edges are added to the reconstructed image. As the edges axe detected and protected, and the NSBT is used, the proposed algorithm reaches the state-of-the-art effect which realizes both despeckling and preserving edges and details simultaneously. Experimental results show that both the subjective visual effect and the mainly objective performance indexes of the proposed algorithm outperform that of both Bayesian wavelet shrinkage with edge detection and Bayesian least square-Gaussian scale mixture （BLS-GSM）.

关键词： computer image processing synthetic aperture radar speckle edge detection nonsubsampled second generation bandelet transform Canny operator threshold shrinkage.

Impact of the Size of Training Set on Text Categorization

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Impact of the Size of Training Set on Text Categorization

DOPPLERLET BASED TIME-FREQUENCY REPRESENTATION VIA MATCHING PURSUITS

第三届学生计算语言学研讨会

作者： LI Jingyang, SUN Maosong (State key lab of intelligent technology and systems, Tsinghua University, 100084)

Text Categorization approaches were often tested on different document collections but the pure relation between the size of training set and the classifier performance has rarely been systematically discussed. We carried out experiments on three document collections with term filtering by Chi and term weighting by tfidf, and attempt to reveal in this paper some attention-getting phenomena. A Rocchio-style classifier and a k-nearest neighbor classifier showed quite different characteristics when training set scales.

关键词： Text Categorization Training set

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Journal of Electronics(China) 2001年第3期18卷 217-227页

作者： Zou Hongxing Zhou Xiaobo Dai Qionghai Li Yanda(State key lab. of intelligent technology and systems, Tsinghua University, Beijing 100084) State key lab. of intelligent technology and systems Tsinghua University Beijing 100084

A new time-frequency representation called Dopplerlet transform, which uses the dilated, translated and modulated windowed Doppler signals as its basis functions, is proposed, and the Fourier transform, short-time Fourier transform (including Gabor transform), wavelet transform, and chirplet transform are formulated in one framework of Dopplerlet transform *** is proved that the matching pursuits based on Dopplerlet basis functions are convergent, and that the energy of residual signals yielded in the decomposition process decays exponentially. Simulation results show that the matching pursuits with Dopplerlet basis functions can characterize compactly a nonstationary signal.

关键词： Time-frequency analysis Dopplerlet transform Pseudo time-frequency distribution Matching pursuit

Efficient DPCA SAR imaging with fast iterative spectrum reconstruction method

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Science China(Information Sciences) 2012年第8期55卷 1838-1851页

作者： FANG Jian1,ZENG JinShan1,XU ZongBen1&ZHAO Yao2 1M inistry of Education key lab for intelligent Networks and Network Security Xi'an Jiaotong University,Xi'an 710049,China 2N ational key laboratory of Science and technology on Microwave Imaging&Institute of Electronics,Chinese Academy of Sciences,Beijing 100049,China 1. Ministry of Education key lab for intelligent Networks and Network Security Xi’an Jiaotong University Xi’an 710049 China2. National Key Laboratory of Science and Technology on Microwave Imaging & Institute of Electronics Chinese Academy of Sciences Beijing 100049 China

The displaced phase center antenna(DPCA)technique is an effective strategy to achieve wide-swath synthetic aperture radar(SAR)imaging with high azimuth ***,traditionally,it requires strict limitation of the pulse repetition frequency(PRF)to avoid non-uniform ***,any deviation could bring serious ambiguity if the data are directly processed using a matched *** break this limitation,a recently proposed spectrum reconstruction method is capable of recovering the true spectrum from the nonuniform ***,the performance is sensitive to the selection of the *** regularization based imaging may provide a way to overcome this *** existing time-domain method,however,requires a large-scale observation matrix to be built,which brings a high computational *** this paper,we propose a frequency domain method,called the iterative spectrum reconstruction method,through integration of the sparse regularization technique with spectrum analysis of the DPCA *** approximately expressing the observation in the frequency domain,which is realized via a series of decoupled linear operations,the method performs SAR imaging which is then not directly based on the observation matrix,which reduces the computational cost from O(N2)to O(N log N)(where N is the number of range cells),and is therefore more efficient than the time domain *** sparse regularization scheme,realized via a fast thresholding iteration,has been adopted in this method,which brings the robustness of the imaging process to the PRF *** provide a series of simulations and ground based experiments to demonstrate the high efficiency and robustness of the *** simulations show that the new method is almost as fast as the traditional mono-channel algorithm,and works well almost independently of the PRF ***,the suggested method can be accepted as a practical and efficient wide-swath SAR imaging technique.

关键词： displaced phase center antenna sparse regularization iterative thresholding spectrum reconstruction

The Connotation of Digital Manufacturing Science and Its Expectation

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武汉理工大学学报 2006年第S1期28卷 1-8页

作者： ZHOU Zude,LIU Quan (Hubei Digital Manufacturing key lab, Wuhan University of technology, Wuhan 430070,China) Hubei Digital Manufacturing key lab Wuhan University of TechnologyWuhan 430070China

After reviewing the phylogeny of manufacturing activities and manufacturing science and summarizing the application actuality of digital manufacturing (DM) technologies in manufacturing, the theory supporting system of digital manufacturing science (DMS) were deeply researched, including calculation manufacturing science and manufacturing informatics, bionics mechanics, manufacturing intelligent science and technical management science and so on. Then the connation of digital manufacturing technologies were dissertated, includes the digital technology set of product life-cycle, the digital manufacturing resources technology set, the manufacturing information technology set and technology characterizations of digital products. The developing directions of DMS in future were put forward at last.

关键词： digital manufacturing science (DMS) theory support system technical connotation expectation

Investing and Pricing with Supply Uncertainty in Electricity Market:A General View Combining Wholesale and Retail Market

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China Communications 2015年第3期12卷 20-34页

作者： LI Xiaobo GAO Li WANG Gongpu GAO Feifei WU Qingwei Beijing University of Posts and Telecommunications School of Digital Media and Design Arts Beijing University of Posts and Telecommunications School of Computer and Information technology Beijing Jiaotong University Department of Automation Tsinghua UniversityState Key Lab of Intelligent Technologies and SystemsTsinghua National Laboratory for Information Science and Technology(TNList)

Renewable energy,such as wind and solar energy,may vary signifi cantly over time and locations depending on the weather and the climate *** leads to the supply uncertainty in the electricity(power) market with renewable energy integrated to power *** this paper,electricity in the market is classified into two types:stablesupply electricity(SSE) and unstablesupply electricity(USE).We investigate the investment and pricing strategies under the electricity supply uncertainty in wholesale and retail electricity *** particular,our model combines the wholesale and retail market and capture the dominant players,i.e.,consumers,power plant(power operator),and electricity *** derive the market behaviors of these players,we formulate the market decision problems as a multistage Stackelberg *** solving the game model,we obtain the optimal,with closedform,wholesale investment and retail pricing strategy for the *** also obtain the energy supplier's best price mechanism numerically under certain *** fi nd the price of SSE being about 1.4 times higher than that of USE will benefi t energy supplieroptimally,under which power plant's optimal strategy of investing is to purchase USE about 4.5 times much more than SSE.

关键词： electricity supply with uncertainty electricity investment electricity pricing wholesale market retail market Stackelberg game

intelligent Fault Diagnosis Based on Robust Observer

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Intelligent Fault Diagnosis Based on Robust Observer

On degrees of freedom of the cellular network

2003年中国智能自动化会议

作者： HAO Han Yong, SUN ZengQi (State key lab of intelligent technology and systems, Department of Computer Science and technology, Tsinghua University Beijing, 100084, P.R.China)

With an increasing demand for higher performance, more safety and reliability of dynamic systems, fault diagnosis has received more and more research interests in recent years. In this paper, a slight improvement on algorithm of robust observer is proposed first. Using an instance of the 3-tank system, the robust performance of robust observer is discussed. Then, by applying neural network on choosing of threshold, the adaptability of observer is improved.

关键词： fault diagnosis robust observer neural network

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Science China(Information Sciences) 2010年第05期53卷 1034-1043页

作者： SUN Jun 1,2 , LIU YingZhuang 1,2 & ZHU GuangXi 1,2 1 Department of Electronics and Information Engineering, Huazhong University of Science and technology, Wuhan 430074, China 2 Division of Optical Network and intelligent Communication, Wuhan National laboratory for Optoelectronics, Wuhan 430074, China 1. Department of Electronics and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of Optical Network and Intelligent Communication Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (e.g., base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of interference alignment, we are able to exactly characterize the sum degrees of freedom (DoF) of the network when the channel coefficients are timeor frequency-varying, which equals KM K+min(M,K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there also exists the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprising result.

关键词： capacity degrees of freedom cellular network interference alignment interference channel MIMO