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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 1. Department of Machine Intelligence School of Electronics Engineering and Computer Science Peking University Beijing 100871 China2. Key Laboratory of Machine Perception Ministry of Education Peking University Beijing 100871 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

Towards a degradation-based mechanism for adaptive overload control

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science china(Information sciences) 2012年第12期55卷 2708-2722页

作者： WANG ZiYou 1,2,ZHOU MingHui 1,2 & MEI Hong 1,2 1 Software Institute,school of electronics engineering and computer science,peking university,beijing 100871,china 2 Key Laboratory of High Confidence Software Technologies(peking university),Ministry of Education,beijing 100871,china 1. Software Institute School of Electronics Engineering and Computer Science Peking University Beijing 100871 China 2. Ministry of Education Key Laboratory of High Confidence Software Technologies (Peking University) Beijing 100871 China

Uncontrolled overload is one of the major causes of the system's decline in reliability and performance for web *** also harms the construction of trustworthy *** paper presents a degradationbased mechanism to adaptively control overload in complex,dynamic web *** our mechanism,the bottlenecks in the application's performance are determined by internally monitoring the performance and resource utilization state of the application,which is decomposed into a set of *** locating the bottlenecks,two decision algorithms are proposed to dynamically and adaptively generate proper degradation plans without *** degrading the service which consumes critical resources and has a low priority from the perspective of business logic,the application can keep providing key services even when overload *** implement a prototype and conduct a case study on a wiki *** also evaluate our approach and demonstrate its effectiveness in simulated overload *** handling overload,we make a breakthrough in building trustworthy software in an open,dynamic and rapidly changing environment.

关键词： overload service degradation resource monitoring performance management

Singularity detection of the rabbit electrocardiogram:An evolutionary spectral method

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Progress in Natural science:Materials International 2009年第10期19卷 1317-1326页

作者： Xinyuan Liua,Dingwu He a,Liuqing Pei b,Suming Zhanga a school of electronics engineering and computer science,peking university,beijing 100871,china b College of Information science and engineering,beijing Normal university,beijing 100875,china [a]school of electronics engineering and computer science Peking University Beijing 100871 China [b]College of Information science and engineering Beijing Normal University Beijing 100875 China

The time-frequency characteristics of the spectral density of non-stationary signals(NSS) in the neighborhood of an instant time point can be determined using the evolutionary spectral *** experimental rabbit model involving ligation of the left anterior descending coronary artery to simulate the physiology of early phase myocardial ischemia(EPMI) has been previously ***,EPMI derived from left coronary artery stenosis is the main symptom of coronary heart diseases including acute myocardial ***,we propose a new algorithm for estimating the evolutionary spectral density functions,which is an effective approach to determine the instantaneous frequency spectra(IFS) of NSS under the uncertainty principle in the time-frequency *** localization singularity information in the data recorded from a living system could be detected by means of the ***(ECG) data recorded from experimental rabbits were analyzed with the new *** showed that the Q’s value of the evolutionary spectral quality number of the QRS-complex data was the characteristic parameter of ECG,and there was a matched connection between the time-frequency characteristics of QRS-complex data and the myocardial ischemia symptoms of the *** results provide valuable information regarding features of the EPMI for use in clinical diagnoses.

关键词： Non-stationary signals Electrocardiogram(ECG) Evolutionary spectrum Instantaneous frequency spectrum(IFS) Myocardial ischemia

A new algorithm for fast mining frequent itemsets using N-lists

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science china(Information sciences) 2012年第9期55卷 2008-2030页

作者： DENG ZhiHong ,WANG ZhongHui & JIANG JiaJian Key Laboratory of Machine Perception(Ministry of Education),school of electronics engineering and computer science,peking university,beijing 100871,china 1. Key Laboratory of Machine Perception (Ministry of Education) School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

Mining frequent itemsets has emerged as a fundamental problem in data mining and plays an essential role in many important data mining *** this paper,we propose a novel vertical data representation called N-list,which originates from an FP-tree-like coding prefix tree called PPC-tree that stores crucial information about frequent *** on the N-list data structure,we develop an efficient mining algorithm,PrePost,for mining all frequent *** of PrePost is achieved by the following three ***,N-list is compact since transactions with common prefixes share the same nodes of the ***,the counting of itemsets’ supports is transformed into the intersection of N-lists and the complexity of intersecting two N-lists can be reduced to O(m + n) by an efficient strategy,where m and n are the cardinalities of the two N-lists ***,PrePost can directly find frequent itemsets without generating candidate itemsets in some cases by making use of the single path property of *** have experimentally evaluated PrePost against four state-of-the-art algorithms for mining frequent itemsets on a variety of real and synthetic *** experimental results show that the PrePost algorithm is the fastest in most *** though the algorithm consumes more memory when the datasets are sparse,it is still the fastest one.

关键词： data mining frequent itemset mining data structure N-lists algorithm

A community-centric approach to automated service composition

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science china(Information sciences) 2010年第1期53卷 50-63页

作者： LIU XuanZhe1,2, HUANG Gang1,2 & MEI Hong1,2 1school of electronics engineering and computer science, peking university, beijing 100871, china 2Key Laboratory of High Confidence Software Technologies, Ministry of Education, peking university, beijing 100871, china 1. school of electronics engineering and computer science Peking University Beijing 100871 China2. Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing 100871 China

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. Firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

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 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

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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A software architecture centric self-adaptation approach for Internetware

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science in china(Series F) 2008年第6期51卷 722-742页

作者： MEI Hong1,2, HUANG Gang1,2, LAN Ling1,2 & LI JunGuo1,2 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 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

Being one of the basic features of Internetware, self-adaptation means that the software system can monitor its runtime state and behavior and adjust them when necessary according to pre-defined policies. Focusing on the three fundamental issues of self-adaptation, including the scope, operability and trustworthiness, a software architecture （SA） centric approach for Internetware＇s self-adaptation is presented in this paper. All of the self-adaptive actions, i.e. monitoring, analyzing, planning and executing, are performed based on SA. In detail, runtime state and behavior of Internetware are represented and changed in the form of runtime soft- ware architecture. The knowledge for self-adaptation is captured, organized and reasoned in the form of SA so that automatic analysis and decision-making are achieved.

关键词： Internetware self-adaptation software architecture middleware

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Online approach to feature interaction problems in middleware based system

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science in china(Series F) 2008年第3期51卷 225-239页

作者： HUANG Gang1,2 LIU XuanZhe1,2 & MEI Hong1,2 1 Key Laboratory of High Confidence Software Technologies, Ministry of Education, peking university, beijing 1000871, china 2.school of electronics engineering and computer science, peking university, beijing 100871, china Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing 1000871 China school of electronics engineering computer science Peking University Beijing 100871 China

As a popular infrastructure for distributed systems running on the Internet, middleware has to support much more diverse and complex interactions for coping with the drastically increasing demand on information technology and the extremely open and dynamic nature of the Internet. These supporting mechanisms facilitate the development, deployment, and integration of distributed systems, as well as increase the occasions for distributed systems to interact in an undesired way. The undesired interactions may cause serious problems, such as quality violation, function loss, and even system crash. In this paper, the problem is studied from the perspective of the feature interaction problem （FIP） in telecom, and an online approach to the detection and solution on runtime systems is proposed. Based on a classification of middleware enabled interactions, the existence of FIP in middleware based systems is illustrated by four real cases and a conceptual comparison between middleware based systems and telecom systems. After that, runtime software architecture is employed to facilitate the online detection and solution of FIP. The approach is demonstrated on J2EE （Java 2 Platform Enterprise Edition） and applied to detect and resolve all of the four real cases.

关键词： feature interaction middleware reflective software architecture

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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 1. Key Laboratory of Machine Perception (MOE) Department of Machine Intelligence School of Electronics Engineering and Computer Science Peking University Beijing 100871 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)