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A new intelligent prediction system model-the compound pyramid model

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science china(Information sciences) 2012年第3期55卷 723-736页

作者： YANG BingRu , QU Wu, WANG LiJun & ZHOU Ying school of Information engineering, university of science and Technology beijing, beijing 100083, china 1. school of Information engineering University of Science and Technology Beijing Beijing 100083 China

A current development trend in research on intelligent systems is to optimize a general intelligent prediction system into an individuation intelligent prediction system that is applied in specialized fields. Protein structure prediction is a challenging international issue. In this paper, we propose a new intelligent prediction system model, designed as a multi-layer compound pyramid model, for predicting secondary protein structure. The model comprises four independent intelligent interfaces and several knowledge discovery methods. The model penetrates throughout the domain knowledge, with the effective attributes chosen by Causal Cellular Automata. Furthermore, a high pure structure database is constructed for training. On the RS126 dataset, the overall state per-residue accuracy, Q3, reached 83.99%, while on the CB513 dataset, Q3 reached 85.58%. Meanwhile, on the CASP8 sequences, the results are superior to those produced by other methods, such as Psipred, Jpred, APSSP2 and BehairPred. These results confirm that our method has a strong generalization ability, and that it provides a model for the construction of other intelligent systems.

关键词： knowledge discovery intelligent prediction system model compound pyramid model

ESTIMATION OF BASIS EXPANSION MODELS FOR DOUBLY SELECTIVE CHANNELS

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Journal of electronics(china) 2008年第1期25卷 115-119页

作者： Liu Yingnan Gao Yonghui Zhang Nu Liang Qinglin school of electronics engineering and computer science Peking University Beijing 100871 China Dfh Satellite Co. Ltd Beijing 100871 China

By analyzing the relationship between Basis Expansion Model (BEM) and Doppler spectrum, this letter proposed a quasi-MMSE-based BEM estimation scheme for doubly selective channels. Based on the assumption that the basis coefficients are approximately independent and have the same variance for the same channel tap, the quasi-MMSE estimation shows approximately optimal performance and is robust to noise. Moreover, it can avoid a high Peak-to-Average Power Ratio (PAPR) by using continuous pilots. Performance of the proposed estimation scheme has been shown with computer simulations.

关键词： Channel estimation Doubly selective channel Basis Expansion Model (BEM) Meansquare error

ON CONTROLLABILITY FOR STOCHASTIC CONTROL SYSTEMS WHEN THE COEFFICIENT IS TIME-VARIANT

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Journal of Systems science & Complexity 2010年第2期23卷 270-278页

作者： Feng LIU Shige PENG school of ElecLronics and Information engineering Beijing Jiaotong University Beijing 100044 China. school of Mathematics and System sciences Shandong University Ji'nan 250100 China

This paper investigates the controllability problem of time-variant linear stochastic controlsystems.A sufficient and necessary condition is established for stochastic exact controllability,whichprovides a useful algebraic criterion for stochastic control ***,when the stochasticsystems degenerate to deterministic systems,the algebraic criterion becomes the counterpart for thecomplete controllability of deterministic control systems.

关键词： Backward stochastic differential equation (BSDE) E-well-posedness Stochastic controlsystem stochastic exact controllability.

Intelligent Control on Hot Strip Coiling Temperature

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 147-150页

作者： Heping Liu Yanlong Zhao(Information engineering school, university of science and Technology Bejing, beijing 100083, china)(Handan Iron & Steel (Group) Co, Handan 056015, china) Information engineering school University of Science and Technology Beijing Beijing 100083 China Handan Iron and Steel (Group) Co. Handan 056015 China

A new intelligent control scheme for hot strip coiling temperature is presented. In this scheme, the prediction mode1 of finishing temperature and the presetting model of main cooling zone are establish based on BP neural network, the feed-forward open-loop control model of main cooling zone is constructed based on T-S fuzzy neural network, a new improved structure of T-S fuzzy neural network is developed, and the feedback close-loop control model of precision cooling zone is obtained based on fuzzy control. The effectiveness of the proposed scheme has been demonstrated by computer simulation with a satisfactory result.

关键词： coiling temperature control laminar cooling fuzzy control neural network, fuzzy neural network

More efficient automatic repair of large-scale programs using weak recompilation

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science china(Information sciences) 2012年第12期55卷 2785-2799页

作者： QI YuHua 1,MAO XiaoGuang 1,WEN YanJun 1,DAI ZiYing 1 & GU Bin 2 1 school of computer,National university of Defense Technology,Changsha 410073,china 2 beijing Institute of Control engineering,beijing 100190,china 1. school of computer National University of Defense Technology Changsha 410073 China2. Beijing Institute of Control Engineering Beijing 100190 China

Automatically repairing a bug can be a time-consuming process especially for large-scale programs owing to the significant amount of time spent recompiling and reinstalling the patched *** reduce this time overhead and speed up the repair process,in this paper we present a recompilation technique called weak *** weak recompilation,we assume that a program consists of a set of components,and for each candidate patch only the altered components are recompiled to a shared *** original program is then dynamically updated by a function indirection *** advantage of weak recompilation is that redundant recompilation cost can be avoided,and while the reinstallation cost is completely eliminated as the original executable program is not modified at *** maximum applicability of weak recompilation we created WAutoRepair,a scalable system for fixing bugs with high efficiency in large-scale C *** experiments on real bugs in widely used programs show that our repair system significantly outperforms Genprog,a wellknown approach to automatic program *** the wireshark program containing over 2 million lines of code,WAutoRepair is over 128 times faster in terms of recompilation cost than Genprog.

关键词： weak recompilation efficiency automated program repair automated debugging experiment

P2P traffic optimization

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science china(Information sciences) 2012年第7期55卷 1475-1492页

作者： ZHANG GuoQiang 1,2 ,TANG MingDong 3 ,CHENG SuQi 2,4 ,ZHANG GuoQing 2 ,SONG HaiBin 5 ,CAO JiGuang 6 & YANG Jing 7 1 school of computer science and Technology,Nanjing Normal university,Nanjing 210046,china 2 Institute of Computing Technology,Chinese Academy of sciences,beijing 100190,china 3 school of computer science and engineering,Hunan university of science and Technology,Xiangtan 411201,china 4 Graduate university of Chinese Academy of sciences,beijing 100190,china 5 Nanjing R&D Center,Huawei Technologies,Nanjing 210012,china 6 china Academy of Telecommunication Research of MIIT,beijing 100191,china 7 china Mobile Research Institute,beijing 100053,china 1. school of computer science and Technology Nanjing Normal University Nanjing 210046 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 China4. Graduate University of Chinese Academy of Sciences Beijing 100190 China5. Nanjing R&D Center Huawei Technologies Nanjing 210012 China6. China Academy of Telecommunication Research of MIIT Beijing 100191 China7. China Mobile Research Institute Beijing 100053 China

Peer-to-peer (P2P) based content distribution systems have emerged as the main form for content distribution on the Internet,which can greatly reduce the distribution cost of content providers and improve the overall system ***,the mismatch between the overlay and underlay networks causes large volume of redundant traffic,which intensifies the tension between P2P content providers and ***,how to efficiently use network resources to reduce the traffic burden on the ISPs is crucial for the sustainable development of P2P *** paper surveys the state-of-art P2P traffic optimization technologies from three perspectives:P2P cache,locality-awareness and data *** details,comparison between these technologies and their applicabilities are presented,followed by a discussion of the issues that remain to be addressed and the direction of future content distribution research.

关键词： P2P traffic localization P2P traffic optimization P2P cache locality-awareness network coding content-centric network

Optimization design study of low-Reynolds-number high-lift airfoils for the high-efficiency propeller of low-dynamic vehicles in stratosphere

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science china(Technological sciences) 2010年第10期53卷 2792-2807页

作者： MA Rong1, ZHONG BoWen2 & LIU PeiQing1 1 Key Laboratory of Fluid Mechanics, Ministry of Education, Institute of Fluid Mechanics, school of Aeronautical science and engineering, beijing university of Aeronautics and Astronautics, beijing 100191, china 2 Department of Aerospace science, school of engineering, Cranfield university, MK43 0AL, United Kingdom 1. Key Laboratory of Fluid Mechanics Ministry of Education Institute of Fluid Mechanics School of Aeronautical Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China2. Department of Aerospace Science School of Engineering Cranfield University MK43 0AL Cranfield UK

Aerodynamic performance of low-Reynolds-number high-lift airfoil makes a great impact on designing a high-efficiency propeller for low-dynamic vehicles in stratosphere. At high altitude,low-Reynolds-number airfoils are supposed to have high lift-drag ratio or high endurance factor at cruising attack angle along with good stall characteristics. To design such a high-performance low-Reynolds-number high-lift airfoil,the paper established a hierarchical multi-objective optimization platform by combing direct search optimization algorithm EXTREM and airfoil flow field solver XFOIL to automatically and quickly calculate aerodynamic performance function of airfoil by computer. It provides an effective solution to multi-point design problem of low-speed low-Reynolds-number airfoil. It can be seen from the results of three typical optimization examples,the new airfoil E387_OPT2,FX63-137_OPT2 and S1223_OPT2 based on hot low-Reynolds-number high-lift airfoils (Eppler 387 airfoil,Wortmann FX63-137 airfoil and S1223 airfoil) can meet the optimization design requirements and have very good aerodynamic characteristics in both design state and non-design state. Thus,the applicability and effectiveness of hierarchical multi-objective optimization platform are verified.

关键词： multi-objective optimization low Reynolds number airfoil EXTREM hierarchical multi-objective optimization

Video motion stitching using trajectory and position similarities

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science china(Information sciences) 2012年第3期55卷 600-614页

作者： CHEN XiaoWu, LI Qing , LI Xin & ZHAO QinPing State Key Laboratory of Virtual Reality Technology and Systems, school of computer science and engineering, Beihang university, beijing 100191, china 1. State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and Engineering Beihang University Beijing 100191 China

Stitching motions in multiple videos into a single video scene is a challenging task in current video fusion and mosaicing research and film production. In this paper, we present a novel method of video motion stitching based on the similarities of trajectory and position of foreground objects. First, multiple video sequences are registered in a common reference frame, whereby we estimate the static and dynamic backgrounds, with the former responsible for distinguishing the foreground from the background and the static region from the dynamic region, and the latter functioning in mosaicing the warped input video sequences into a panoramic video. Accordingly, the motion similarity is calculated by reference to trajectory and position similarity, whereby the corresponding motion parts are extracted from multiple video sequences. Finally, using the corresponding motion parts, the foregrounds of different videos and dynamic backgrounds are fused into a single video scene through Poisson editing, with the motions involved being stitched together. Our major contributions are a framework of multiple video mosaicing based on motion similarity and a method of calculating motion similarity from the trajectory similarity and the position similarity. Experiments on everyday videos show that the agreement of trajectory and position similarities with the real motion similarity plays a decisive role in determining whether two motions can be stitched. We acquire satisfactory results for motion stitching and video mosaicing.

关键词： video fusion video mosaicing video registration background estimation motion stitching

A study of constraints on the constitutive relationships of electromagnetic medium based on generally acknowledged truths

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science china(Physics,Mechanics & Astronomy) 2005年第5期48卷 541-548页

作者： GUO Huiping1, LIU Xueguan1,2, YIN Hongcheng2, CHAO Zengming2 & HUANG Peikang2 1. school of electronics and Information engineering, Soochow university, Suzhou 215021, china 2. National Electromagnetic Scattering Laboratory, beijing 100854, china 1. school of electronics and Information engineering Soochow University 215021 Suzhou China 2. National Electromagnetic Scattering Laboratory 100854 Beijing China

The study of constraints on the constitutive relationships of electromagnetic media is of great importance in the aspects of the medium characteristics analysis, the new article material synthesis and the medium parameters reconstruction, etc. According to the fact that the constitutive relationships should not conflict with the general physical laws, the constraints that the constitutive relationships of electromagnetic medium must satisfy have been summarized in this paper. These constraints include determinacy principle, objectivity principle, causality principle and permission principle. And the parameter constraints of the arbitrary linear homogenous time-invariant medium are obtained following the minimum energy consumption principle. This work provides a new way of ascertaining the constitutive relationships of the electromagnetic medium.

关键词： electromagnetic medium, medium parameter constraint, generally acknowledged truths, energy conservation principle, minimum energy consumption principle.