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Active Shape Models Using Scale Invariant Feature Transform

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Journal of Shanghai Jiaotong university(science) 2007年第6期12卷 713-718页

作者：史勇红戚飞虎栾红霞吴国荣 dept. of computer science and eng. Shanghai Jiaotong Univ.

A new active shape models (ASMs) was presented, which is driven by scale invariant feature transform (SIFT) local descriptor instead of normalizing first order derivative profiles in the original formulation, to segment lung fields from chest radiographs. The modified SIFT local descriptor, more distinctive than the general intensity and gradient features, is used to characterize the image features in the vicinity of each pixel at each resolution level during the segmentation optimization procedure. Experimental results show that the proposed method is more robust and accurate than the original ASMs in terms of an average overlap percentage and average contour distance in segmenting the lung fields from an available public database.

关键词： active shape model (ASM) deformable segmentation chest radiograph scale invariant feature transform (SIFT) local descriptor

A Novel Method for Character Segmentation in Natural Scenes

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Journal of Shanghai Jiaotong university(science) 2006年第4期11卷 484-489,497页

作者：徐立戚飞虎蒋人杰朱凯华吴国荣 dept. of computer science and eng. Shanghai Jiaotong Univ.

A new approach to extract and segment characters in natural scenes was proposed in this paper. First, a set of intrinsic features were calculated based on connected components (CCs) extracted by a non-linear Nilblack algorithm. Then, feature propagation was conducted for feature enhancement, under the constraint of the layout relations. Next, candidate CCs were fed into classifiers with the enhanced feature vector. At last, a model-based hierarchical merging (MHM) procedure was presented to obtain understandable characters. The proposed merging algorithm utilized the constraint of text lines for specific languages and dynamically merges CCs into characters. The whole algorithm was evaluated at both pixel level and character level, experimental results showed that the proposed method is effective in detecting scene characters with significant geometric variations, uneven illumination, extremely low contrast and cluttered background.

关键词： character segmentation feature extraction model-based hierarchical merging (MHM)

Content-Based Human Motion Retrieval with Scene Description Language

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Journal of Shanghai Jiaotong university(science) 2006年第4期11卷 452-459,464页

作者：高岩马利庄吴小毛陈志华 dept. of computer science & eng. Shanghai Jiaotong Univ.

As commercial motion capture systems are widely used, more and more 3D motion libraries become available, reinforcing the demand for efficient indexing and retrieving methods. Usually, the user will only have a sketchy idea of which kind of motion to look for in the motion database. As a result, how to clearly describe the user’s demands is a bottleneck for motion retrieval system. This paper presented a framework that can handle this problem effectively for motion retrieval. This content-based retrieval system supports two kinds of query modes: textual query mode and query-by-example mode. In both query modes, user’s input is translated into scene description language first, which can be processed by the system efficiently. By using various kinds of qualitative features and adaptive segments of motion capture data stream, indexing and retrieval methods are carried out at the segment level rather than at the frame level, making them quite efficient. Some experimental examples are given to demonstrate the effectiveness and efficiency of the proposed algorithms.

关键词： computer animation motion retrieval motion indexing

Research on Web Page Automatic Classification Based on Internet News Corpus

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Journal of Shanghai Jiaotong university(science) 2007年第6期12卷 731-735页

作者：蔡巍王永成尹中航 dept. of computer science & eng. Shanghai Jiaotong Univ.

Web pages contain more abundant contents than pure text ,such as hyperlinks,html tags and metadata et *** that Web page categorization is different from pure text. According to Internet Chinese news pages, a practical algorithm for extracting subject concepts from web page without thesaurus was proposed, when incorporated these category-subject concepts into knowledge base, Web pages was classified by hybrid algorithm, with experiment corpus extracting from Xinhua net. Experimental result shows that the categorization performance is improved using Web page feature.

关键词： automatic classification Web pages subject extraction

Buffer Overflow Detection on Binary Code

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Journal of Shanghai Jiaotong university(science) 2006年第2期11卷 224-229页

作者：郑燕飞李晖陈克非 School of Information Security eng. dept. of computer science and eng. Shanghai Jiaotong Univ. Shanghai 200030 China

Most solutions for detecting buffer overflow are based on source code. But the requirement tor source code is not always practical especially for business software. A new approach was presented to detect statically the potential buffer overflow vulnerabilities in the binary code of software. The binary code was translated into assembly code without the lose of the information of string operation functions. The feature code abstract graph was constructed to generate more accurate constraint statements, and analyze the assembly code using the method of integer range constraint. After getting the elementary report on suspicious code where buffer overflows possibly happen, the control flow sensitive analysis using program dependence graph was done to decrease the rate of false positive. A prototype was implemented which demonstrates the feasibility and efficiency of the new approach.

关键词： binary code buffer overflow integer range constraint feature abstract graph

RANDOM COPOLYMER OF PROPYLENE OXIDE AND ETHYLENE OXIDE PREPARED BY DOUBLE METAL CYANIDE COMPLEX CATALYST

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Chinese Journal of Polymer science 2002年第5期20卷 453-459页

作者： Yi-jun Huang Guo-rong Qi Guan-xi Chen Department of Polymer science and eng.neering, Zhejiang University Hangzhou 310027,China dept. of Polymer science and eng. Zhejiang University Hangzhou 310027 China

Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition.

关键词： propylene oxide ethylene oxide double metal cyanide complex

Hierarchical Non-linear Image Registration Integrating Deformable Segmentation

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Journal of Shanghai Jiaotong university(science) 2005年第4期10卷 327-332页

作者： RAN Xin（冉鑫） QI Fei-hu（戚飞虎） dept. of computer science ＆ eng. Shanghai Jiaotong Univ. Shanghai 200030 China

A hierarchical non-linear method for image registration was presented, which integrates image segmentation and registration under a variational framework. An improved deformable model is used to simultaneously segment and register feature from multiple images. The objects in the image pair are segmented by evolving a single contour and meanwhile the parameters of affine registration transformation are found out. After that, a contour-constrained elastic registration is applied to register the images correctly. The experimental results indicate that the proposed approach is effective to segment and register medical images.

关键词： image segmentation image registration deformable model

Deformable Registration of MR Brains with Best Features

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Journal of Shanghai Jiaotong university(science) 2006年第3期11卷 290-295页

作者：吴国荣戚飞虎史勇红栾红霞 dept. of computer science and eng. Shanghai Jiaotong Univ.Shanghai 200030 China

A learning-based deformable registration method was presented for MR brain images. First, best geometric features are selected for each location and each resolution, in order to reduce ambiguity in matching during image registration. The best features are obtained by solving an energy minimization problem, which requires the features to be distinctive around the neighboring points and consistency across training samples. Secondly, the set of active points is hierarchically selected based on their saliency and consistency measurements during registration, which helps to produce accurate registration results. Finally, by incorporating those learned results into the framework of HAMMER, great improvement in both real data and simulated data is achieved.

关键词： deformable registration machine learning best scale selection

A New Software Reliability Framework —— A Extended Cleanroom Model

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High Technology Letters 2001年第2期7卷 42-46页

作者：姚文斌 dept. of computer science and eng. Harbin Institute of Technology Harbin 150001 China

Cleanroom software eng.neering has been proven effective in improving software development quality while at the same time increasing reliability. To adapt to large software system development, the paper presents an extended the Cleanroom model, which integrates object-oriented method based on stimulus history, reversed eng.neering idea, automatic testing and reliability assessment into software development. The paper discusses the architecture and realizing technology of ECM.

关键词： Cleanroom model Stimulus history Object-oriented method Reversed eng.neering Automatic testing Reliability assessment