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Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

Chinese science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3,4,LI ZhengBin2,3 & LEI Yang1 1 department of Physics,peking university,beijing 100871,china 2 department of electrical engineering and computer science,peking university,beijing 100871,china 3 State Key Laboratory of Advanced Optical Communication Systems & Networks,peking university,beijing 100871,china 4 Committee of Yuanpei Honors Program,peking university,beijing 100871,china department of Physics Peking University Beijing China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing China Committee of Yuanpei Honors Program Peking University Beijing China department of electrical engineering and computer science Peking University Beijing China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53 billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

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A malware detection model based on a negative selection algorithm with penalty factor

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science china(Information sciences) 2010年第12期53卷 2461-2471页

作者： ZHANG PengTao 1,2 , WANG Wei 1,2 & TAN Ying 1,2 1 department of Machine Intelligence, School of Electronics engineering and computer science, peking university, beijing 100871, china 2 Key Laboratory of Machine Perception, Ministry of Education, peking university, beijing 100871, china department of Machine Intelligence School of Electronics Engineering and Computer Science Peking University Beijing China Key Laboratory of Machine Perception Ministry of Education Peking University Beijing China

A malware detection model based on a negative selection algorithm with penalty factor (NSAPF) is proposed in this paper. This model extracts a malware instruction library (MIL), containing instructions that tend to appear in malware, through deep instruction analysis with respect to instruction frequency and file frequency. From the MIL, the proposed model creates a malware candidate signature library (MCSL) and a benign program malware-like signature library (BPMSL) by splitting programs orderly into various short bit strings. Depending on whether a signature matches "self", the NSAPF further divides the MCSL into two malware detection signature libraries (MDSL1 and MDSL2), and uses these as a two-dimensional reference for detecting suspicious programs. The model classifies suspicious programs as malware and benign programs by matching values of the suspicious programs with MDSL1 and MDSL2. Introduction of a penalty factor C in the negative selection algorithm enables this model to overcome the drawback of traditional negative selection algorithms in defining the harmfulness of "self" and "nonself", and focus on the harmfulness of the code, thus greatly improving the effectiveness of the model and also enabling the model to satisfy the different requirements of users in terms of true positive and false positive rates. Experimental results confirm that the proposed model achieves a better true positive rate on completely unknown malware and a better generalization ability while keeping a low false positive rate. The model can balance and adjust the true positive and false positive rates by adjusting the penalty factor C to achieve better performance.

关键词： penalty factor negative selection algorithm signature extraction artificial immune system mal- ware detection

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Technical framework for Internetware: An architecture centric approach

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science in china(Series F) 2008年第6期51卷 610-622页

作者： YANG FuQing1,2, Lü Jian3,4 & MEI Hong1,2 1 Key Laboratory of High Confidence Software Technologies (peking university), Ministry of Education, beijing 100871, china 2 School of Electronics engineering and computer science, peking university, beijing 100871, china 3 State Key Laboratory for Novel Software Technology, Nanjing 210093, china 4 department of computer science and Technology, Nanjing university, Nanjing 210093, china Key Laboratory of High Confidence Software Technologies (peking university) Ministry of Education Beijing China School of Electronics engineering and computer science Peking University Beijing China State Key Laboratory for Novel Software Technology Nanjing China department of computer science and Technology Nanjing University Nanjing China

Being a new software paradigm evolved by the Internet, Internetware brings many challenges to the traditional software methods and techniques. Sponsored by the national basic research program （973）, researchers in china have developed an architecture centric technical framework for the definition, incarnation and engineering of Internetware. First of all, a software model for Internetware is defined for what to be, including that Internetware entities should be packaged as components, behaving as agents, interoperating as services, collaborating in a structured and on demand manner, etc. Secondly, a middleware for Internetware is designed and implemented for how to be, including that Internetware entities are incarnated by runtime containers, structured collaborations are enabled by runtime software architecture, Internetware can be managed in a reflective and autonomic manner, etc. Thirdly, an engineering methodology for Internetware is proposed for how to do, including the way to develop Internetware entities and their collaborations by transforming and refining a set of software architectures which cover all the phases of software lifecycle, the way to identify and organize the disordered software assets by domain modeling, etc.

关键词： Internetware component software architecture agent middleware

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Research on dual-stator winding multi-phase high-speed induction generator with rectifier load

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science china(Technological sciences) 2008年第6期51卷 683-692页

作者： WANG XiangHeng1 & WU XinZhen2 1 department of electrical engineering, Tsinghua university, beijing 100084, china 2 department of electrical engineering, Qingdao university, Qingdao 266071, china department of electrical engineering Tsinghua University Beijing China department of electrical engineering Qingdao University Qingdao China

Based on analysis and calculation of the relation between current harmonics and MMF harmonics in the dual-stator winding multi-phase high-speed induction gen-erator with a rectifier load, a new idea, which divides the generator system into two sub-systems to be analyzed individually, is presented. For the sub-system of the 12-phase power winding with a rectifier load, the loop current method is used to establish network equation set in terms of the network graph theory. The numerical stability problem is solved by alternating use of fixed time-step and varied time-step, and the voltage and current with their fundamental components of the power winding are obtained. For the other sub-system of the induction generator with dual-stator winding and solid cage rotor, the electromagnetic field analysis method and the multi-variable optimization approach are combined to get the con-trol winding current and stator frequency. Calculated results well match experiment results, indicating that the new proposed method is of effectiveness and high ac-curacy.

关键词： dual-stator winding induction generator rectifier load MMF analysis loop current method finite element method optimization approach

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Laplacian smoothing transform for face recognition

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science china(Information sciences) 2010年第12期53卷 2415-2428页

作者： GU SuiCheng, TAN Ying & HE XinGui Key Laboratory of Machine Perception (MOE) department of Machine Intelligence, School of Electronics engineering and computer science peking university, beijing 100871, china Key Laboratory of Machine Perception (MOE) department of Machine Intelligence School of Electronics Engineering and Computer Science Peking University Beijing China

In this paper, we investigate how to extract the lowest frequency features from an image. A novel Laplacian smoothing transform (LST) is proposed to transform an image into a sequence, by which low frequency features of an image can be easily extracted for a discriminant learning method for face recognition. Generally, the LST is able to be an efficient dimensionality reduction method for face recognition problems. Extensive experimental results show that the LST method performs better than other pre-processing methods, such as discrete cosine transform (DCT), principal component analysis (PCA) and discrete wavelet transform (DWT), on ORL, Yale and PIE face databases. Under the leave one out strategy, the best performance on the ORL and Yale face databases is 99.75% and 99.4%; however, in this paper, we improve both to 100% with a fast linear feature extraction method for the first time.

关键词： Laplacian smoothing transform (LST) face recognition principal component analysis (PCA) discrete cosine transform (DCT) discrete wavelet transform (DWT) linear discriminant analysis (LDA)

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Predicting Polymerase Ⅱ Core Promoters by Cooperating Transcription Factor Binding Sites in Eukaryotic Genes

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 250-258页

作者： Xiao-Tu MA, Min-Ping QIAN*, and Hai-Xu TANG1 School of Mathematical sciences, peking university and Center for Theoretical Biology, peking university, beijing 100871, china 1department of computer science and engineering, university of California, San Diego, La Jolla CA 92093-0114, USA School of Mathematical sciences Peking University and Center for Theoretical Biology Peking UniversityBeijing 100871 China department of computer science and engineering University of CaliforniaSan Diego La Jolla CA 92093-0114 USA

Several discriminate functions for predicting core promoters that based on the potential cooperation between transcription factor binding sites (TFBSs) are discussed. It is demonstrated that the promoter predicting accuracy is improved when the cooperation among TFBSs is taken into consideration. The core promoter region of a newly discovered gene CKLFSF1 is predicted to locate more than 1.5 kb far away from the 5' end of the transcript and in the last intron of its upstream gene, which is experimentally confirmed later. The core promoters of 3402 human RefSeq sequences, obtained by extending the mRNAs in human genome sequences, are predicted by our algorithm, and there are about 60% of the predicted core promoters locating within the ± 500 bp region relative to the annotated transcription start site.

关键词： promoter transcription factor binding site transcription start site gene finding

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Performance Modeling and Approximate Analysis of Multiserver Multiqueue Systems with Poisson and Self-similar Arrivals

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Journal of university of science and Technology beijing 2001年第2期8卷 145-151页

作者： Zhiguang Shan, Chuang Lin, Yang Yang, Yan Wang (Information engineering School, university of science and Technology beijing, beijing 100083, china) (department of computer science and Technology, Tsinghua university, beijing 100084, china) Information engineering School University of Science and Technology Beijing 100083 China

The problem of state space explosion is still ran outstanding challenge in Markovian performance analysis for multiserver multiqueue (MSMQ) systems. The system behavior of a MSMQ system is described using stochastic high-level Petri net (SHLPN) models, and an approximate performance analysis technique is proposed based on decomposition and refinement methods as well as iteration technique. A real MSMQ system, Web-server cluster, is investigated. The performance of an integrated scheme of request dispatching and scheduling is analyzed with both Poisson and self-similar request arrivals. The study shows that the approximate analysis technique significantly reduces the complexity of the model solution and is also efficient for accuracy of numerical results.

关键词： multiserver multiqueue (MSMQ) system Web-server cluster performance analysis stochastic high-level Petri net (SHLPN) request dispatching request scheduling

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Theory and techniques of data mining in CGF behavior modeling

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science china(Information sciences) 2011年第4期54卷 717-731页

作者： YIN YunFei 1,2,GONG GuangHong 2 & HAN Liang 2 1 College of computer science,Chongqing university,Chongqing 400044,china 2 School of Automation science and electrical engineering,beijing university of Aeronautics and Astronautics,beijing 100083,china College of computer science Chongqing University Chongqing China School of Automation science and electrical engineering Beijing University of Aeronautics and Astronautics Beijing China

For the large quantity of data,rules and models generated in the course of computer generated forces (CGFs) behavior modeling,the common analytical methods are statistical methods based on the tactical rules,tactical doctrine and empirical ***,from the viewpoint of data mining,we can find many of these analytical methods are also each-and-every different data mining *** this paper,we survey the data mining theory and techniques that have appeared in the course of CGF behavior modeling from the viewpoint of data ***,we redefine and reclassify these theories and techniques according to the research requirements of data mining (the knowledge structure of data mining).We aim to help the CGF investigators to learn the key points and the research methods of the data intelligent processing in the CGF behavior modeling,and thus we can provide the references for the colleagues who are engaged in the research and practice of the CGF behavior modeling by this *** also introduce our ongoing work on the CGF behavior modeling based on data mining.

关键词： CGF CGF behavior modeling data mining theory and techniques

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Formation control for networked spacecraft in deep space:with or without communication delays and with switching topology

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science china(Information sciences) 2011年第3期54卷 469-481页

作者： WANG Nan 1,2, ZHANG TianWu 2 & XU JieQiong 1 1 School of Aeronautic science and engineering, beijing university of Aeronautics and Astronautics, beijing 100191, china 2 department of computer science and engineering, Henan Institute of engineering, Zhengzhou 451191, china School of Aeronautic science and engineering Beijing University of Aeronautics and Astronautics Beijing China department of computer science and engineering Henan Institute of Engineering Zhengzhou China

In this paper, several formation controllers are developed with constant and variable connected communication topology for six-degree-of-freedom (6-DOF) networked spacecraft flying in deep space with constant and time-varying communication delays considered. In the control algorithm, any explicit leader does not exist in the formation team and it is required that each spacecraft communicate only with its neighbors and therefore the required communication loads of the whole formation is greatly reduced. The proposed control strategies allow that each spacecraft can track its desired position and attitude and simultaneously the whole group moves to the desired formation and obtain its desired relative attitudes with its neighbors. Simulation results demonstrate the effectiveness of the proposed controllers.

关键词： deep space graph theory formation control communication topology delays

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Salient region detection and segmentation for general object recognition and image understanding

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science china(Information sciences) 2011年第12期54卷 2481-2490页

作者： HUANG TieJun 1 , TIAN YongHong 1 , LI Jia 2 & YU HaoNan 11 National engineering Laboratory for Video Technology, School of electrical engineering and computer science, peking university, beijing 100871, china 2 Key Laboratory of Intelligent Information Processing, Institute of Computing Technology, Chinese Academy of sciences, beijing 100190, china National engineering Laboratory for Video Technology School of Electrical Engineering and Computer Science Peking University Beijing China Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China

General object recognition and image understanding is recognized as a dramatic goal for computer vision and multimedia retrieval. In spite of the great efforts devoted in the last two decades, it still remains an open problem. In this paper, we propose a selective attention-driven model for general image understanding, named GORIUM (general object recognition and image understanding model). The key idea of our model is to discover recurring visual objects by selective attention modeling and pairwise local invariant features matching on a large image set in an unsupervised manner. Towards this end, it can be formulated as a four-layer bottom-up model, i.e., salient region detection, object segmentation, automatic object discovering and visual dictionary construction. By exploiting multi-task learning methods to model visual saliency simultaneously with the bottom-up and top-down factors, the lowest layer can effectively detect salient objects in an image. The second layer exploits a simple yet effective learning approach to generate two complementary maps from several raw saliency maps, which then can be utilized to segment the salient objects precisely from a complex scene. For the third layer, we have also implemented an unsupervised approach to automatically discover general objects from large image set by pairwise matching with local invariant features. Afterwards, visual dictionary construction can be implemented by using many state-of-the-art algorithms and tools available nowadays.

关键词： object recognition image understanding visual saliency salient object segmentation visual dictionary

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