22766407
Watermarking Abstract Tree-Structured Data
Digital watermarking techniques have been successfully applied in multimedia data such as image, audio, video, etc. With the rapid development of Internet, the requirement of copyright and integrity protection over semi-structured data, such as XML documents and complex hypertext content, is becoming more and more urgent. However, it is more challenging to apply the effective watermarking schemes into semi-structured data, because watermark for semi-structured data must have the dual protection feature toward both structure and content. In general, most semi-structured data can be represented as tree. Therefore, in this paper, we propose a novel watermark scheme for tree-structured data based on the value lying both in the tree structure and in the node content, which gives a comprehensive protection for both node content and structure of tree. The experiments on the robustness of the solution against various forms of attacks are conducted. The results highlight correctness and efficiency of our solution.
5747087
Efficient Processing of Warping Time Series Join of Motion Capture Data
Discovering non-trivial matching subsequences from two time series is very useful in synthesizing novel time series. This can be applied to applications such as motion synthesis where smooth and natural motion sequences are often required to be generated from existing motion sequences. We first address this problem by defining it as a problem of l-e-join over two time series. Given two time series, the goal of l-e-join is to find those non-trivial matching subsequences by detecting maximal l-connections from the e-matching matrix of the two time series. Given a querying motion sequence, the l-e-join can be applied to retrieve all connectable motion sequences from a database of motion sequences. To support efficient l-e-join of time series, we propose a two-step filter-and-refine algorithm, called Warping Time Series Join (WTSJ) algorithm. The filtering step serves to prune those sparse regions of the e-matching matrix where there are no maximal l-connections without incurring costly computation. The refinement step serves to detect closed l-connections within regions that cannot be pruned by the filtering step. To speed up the computation of e-matching matrix, we propose a block-based time series summarization method, based on which the block-wise e-matching matrix is first computed. Lots of pairwise distance computation of elements can then be avoided by applying the filtering algorithm on the block-wise e-matching matrix.Extensive experiments on l-e-join of motion capture sequences are conducted. The results confirm the efficiency and effectiveness of our proposed algorithm in processing l-e-join of motion capture time series.
15447660
A logical replication-based intrusion detection approach for CSCW system
With the rapid development of CSCW techniques, CSCW system security has been of much attention. Its major challenge comes from malicious attacks, which cannot be handled by traditional security mechanisms, such as authorization, access control, encryption, etc. Although there existed some intrusion detection systems, current researches on intrusion detection are still insufficient in accuracy and efficiency for two reasons: firstly, most of them implement malicious transaction detection only by matching samples with predefined patterns; secondly, most current researches mainly resort to semantic analyzing or even only manual interventions to judge the malicious attacks. Inspired by the replication technique, we propose and implement a novel logical replication-based intrusion detection solution for CSCW system in this paper. It provides an additional layer of defense against application attacks, especially program attacks. The approach entitles the system to detect malicious intrusions efficiently at low false positive rate.
15163337
A Database Encryption Scheme for Enhanced Security and Easy Sharing
Database encryption is a crucial technique in the security mechanisms of database. It is widely recognized as one of the key issues of data security. Current techniques of sharing the keys and the encrypted data for databases are neither convenient nor flexible in the real applications. Inspired by the PGP technique, we propose a novel database encryption scheme for enhanced data sharing inside a database, while preserving data privacy. It is characterized by both the fast speed of the conventional encryption and the convenience of key distribution of public key encryption. It also provides secured storage for security related data and effective key management, which enables the encrypted data to be shared conveniently. The scheme has been implemented and successfully applied on Oscar, a commercial DBMS developed by us
17533153
OTJFast: Processing Ordered XML Twig Join Fast
Thanks to standard specifications for Web services, more and more data is represented and exchanged in XML. Efficiently finding all occurrences of a twig pattern is a core operation of XML query processing. Recently, a large number of holistic twig join algorithms have been proposed, however ordered XML twig join has been ignored in most of them. In this paper we design a novel algorithm called OTJFast to process ordered XML twig joins efficiently which only need to access the elements of the leaf query nodes. Experimental results show the benefits of our algorithm in term of the size of intermediate results, the number of element reads and the execution time.
18102767
Resilient Rights Protection for Product Data
With the development of advance manufacture applications, enterprise must interact with their suppliers and customers to share more product data information. Consequently, copyright and integrity protection over product data is becoming an urgent requirement. Product data information consists of two parts: product structure and part content, besides protecting the three-dimensional (3D) model of part by watermarking, we also need to protect product structure information, which describes the relations among product parts and can be represented as a tree. In this paper, based on the 3D polygonal meshes watermark technology, the structure/semi-structure data watermark technologies and the idea of Fractal, we propose a novel watermark scheme for tree-structure product data with the value lying both in product structure and in part node content, which gives a more comprehensive and resilient right protection for both part node content and product structure. Moreover it is particularly effective when resisting invertibility attacks
1757195
Combining linear discriminant functions with neural networks for supervised learning
A novel supervised learning method is proposed by combining linear discriminant functions with neural networks. The proposed method results in a tree-structured hybrid architecture. Due to constructive learning, the binary tree hierarchical architecture is automatically generated by a controlled growing process for a specific supervised learning task. Unlike the classic decision tree, the linear discriminant functions are merely employed in the intermediate level of the tree for heuristically partitioning a large and complicated task into several smaller and simpler subtasks in the proposed method. These subtasks are dealt with by component neural networks at the leaves of the tree accordingly. For constructive learning, growing and credit-assignment algorithms are developed to serve for the hybrid architecture. The proposed architecture provides an efficient way to apply existing neural networks (e.g. multi-layered perceptron) for solving a large scale problem. We have already applied the proposed method to a universal approximation problem and several benchmark classification problems in order to evaluate its performance. Simulation results have shown that the proposed method yields better results and faster training in comparison with the multilayered perceptron.
6566254
On k-Median clustering in high dimensions
We study approximation algorithms for <i>k</i>-median clustering. We obtain small coresets for <i>k</i>-median clustering in metric spaces as well as in Euclidean spaces. Specifically, in R<sup>d</sup>, those coresets are of size with only <i>polynomial</i> dependency on <i>d</i>. This leads to a (1 + ε)-approximation algorithm for <i>k</i>-median clustering in R<sup>d</sup>, with running time <i>O</i>(<i>ndk</i> +2<sup>(k/ε)<sup><i>o</i>(1)</sup></sup><i>d</i><sup>2</sup><i>n</i>σ), for any σ > 0. This is an improvement over previous results [5, 20, 21]. We also provide fast constant factor approximation algorithms for <i>k</i>-median clustering in finite metric spaces.We use those coresets to compute (1 + ε)-approximation <i>k</i>-median clustering in the streaming model of computation, using only <i>O</i>(<i>k</i><sup>2</sup><i>de</i><sup>-2</sup>log<sup>8</sup> <i>n</i>) space, where the points are taken from R<sup>d</sup>. This is the first streaming algorithm, for this problem, that has space complexity with only <i>polynomial</i> dependency on the dimension.
5841267
The Data Mining Technology Based on CIMS and its Application on Automotive Remanufacturing
Nowadays, with the development of computer technology, data mining has been widely used in various fields. This paper describes a CIMSMINER that combines the data mining with CIMS (computer integrated manufacturing system) and instructs its objectives, model, physical architecture and methods. Considering the characteristics of remanufacturing of automotive products in China, the CIMSMINER is used to get the information concourse together and obtain the data mining results to help the improvement of products. The application in automotive remanufacturing is a reform to make the automotive product information chain be not only an information carrier, but also an information miner. Currently, the government strongly emphasizes energy saving and emission reducing, which is closely related to the sustainable development of China. Obviously, CIMSMINER is an effective tool to support the implementation of this policy.
15908834
Ensemble Learning with Active Data Selection for Semi-Supervised Pattern Classification
Unlike traditional pattern classification, semi-supervised learning provides a novel technique to make use of both labeled and unlabeled data for improving the performance of classification. In general, there are two critical issues for semi-supervised learning of discriminative classifiers; i.e., how to create an initial classifier of a good generalization capability with the limited labeled data and the how to make an effective use of unlabeled data without degradation of the established classifier. To tackle two aforementioned problems, we propose an ensemble learning approach based on a recent active data selection strategy, where ensemble learning would yield good generalization and active data selection tends to choose the unlabeled data more likely resulting in an improvement during semi-supervised learning. By using an ensemble of K-NN classifiers, we demonstrate the effectiveness of our approach on a synthetic data classification and a facial expression recognition tasks.
15411856
Prediction of the Number of Helices for the Twilight Zone Proteins
Protein structure prediction is one of the core research areas in bioinformatics. This paper addresses the protein secondary structure prediction problem for the twilight zone proteins, which are characterized by low, about 25% homology to the sets of known sequences. The commonly used sequence alignment based algorithms fail to provide accurate prediction for sequences of such low homology, and thus alternative solutions should be sought. We propose a novel method that aims at the prediction of the number of helical structures based on the twilight zone protein sequences. The method is based on a custom designed and compact feature based sequences representation and applies a decision tree prediction algorithm. The performed experimental study shows superiority of the proposed method over three other prediction algorithms and the results provided by YASPIN algorithm, which is a state-of-the-art alignment based secondary structure prediction method designed using low homology sequences