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Web application server replication scheme for complex transaction patterns

Ruan Jian Xue Bao/Journal of software 2008年第2期19卷 432-445页

作者： Zuo, Lin Liu, Shao-Hua Feng, Yu-Lin Wei, Jun Li, Yang Technology Center of Software Engineering Institute of Software Chinese Academy of Sciences Beijing 100080 China Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100080 China Graduate University Chinese Academy of Sciences Beijing 100049 China

The support of reliability as adopted in conventional replication or transaction processing techniques is not enough due to their distinct objectives: Replication guarantees the liveness of computational operations by using forward error recovery, while transaction processing guarantees the safety of application data by using backward error recovery. Combining the two mechanisms for stronger reliability is a challenging task. Current solutions, however, are typically on the assumption of simple transaction pattern where only a server transaction exists at the middle-tier application server, and seldom think about some complex patterns, such as client transaction or nested transaction. To address this problem, four typical transaction patterns in J2EE application are recognized first. Then a Web application server replication scheme based state synchronization point concept, RSCTP (replication scheme for complex transaction pattern), is presented to uniformly provide exactly-once semantic reliability support for these complex transaction patterns. In this scheme, EJB components are replicated to endow business logics with high availability. In addition, by replicating transaction coordinator, the blocking problem of 2PC protocol during distributed transactions processing is eliminated. Different transaction scenarios are also discussed to illustrate the effectivity of this scheme. This scheme has been implemented, and it has been integrated into J2EE compatible application server, OnceAS, and the performance evaluation shows that its overhead is acceptable.

关键词： Web services

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Information transmission model for covert channel

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Tien Tzu Hsueh Pao/Acta Electronica Sinica 2008年第11期36卷 2216-2219页

作者： Yao, Li-Hong Zi, Xiao-Chao Li, Jian-Hua School of Information Security Engineering Shanghai Jiaotong University Shanghai 200240 China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

Covert channels cause serious security threat to information systems, and the research on the information transmission principle of the channels is crucial to detect and eliminate them. Covert channel is essentially a communication channel to transmit information illegally. In the paper, an information system is firstly regarded as a communication channel, and the information transmission in it is considered as a regular communication process. Then, an information transmission model is introduced, and it can present clearly the information transmission principle and the communication process including encoding, concocting and decoding. Lastly, a method of calculating the communication bandwidth is discussed.

关键词： Information systems

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Scheduling aircraft landing based on clonal selection algorithm and receding horizon control

Scheduling aircraft landing based on clonal selection algori...

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11th International IEEE Conference on Intelligent Transportation Systems, ITSC 2008

作者： Jia, Xiaolan Cao, Xianbin Guo, Yuanping Qiao, Hong Zhang, Jun University of Science and Technology of China Anhui Province Key Laboratory of Software in Computing and Communication Hefei 230026 China Institute of Automation Chinese Academy of Sciences Beijing 100080 China School of Electronic and Information Engineering Beihang University Beijing 100083 China

ISBN: (纸本)9781424421121

The task of Aircraft Landing Scheduling (ALS) is to give a landing sequence and landing times for a given set of aircrafts where many constraints must be satisfied. ALS is an NP-hard problem with large-scale and multi-constraint characteristics, thus it is hard to find optimal solution efficiently. In this paper, a hybrid algorithm of Clonal Selection Algorithm (CSA) and Receding Horizon Control (RHC) was proposed for ALS problem. In details, constrained CSA based on infeasibility degree (IFD) schedules aircrafts in current receding horizon, and then RHC repeats that optimization procedure using excellent gene segment spread (EGSS) until all aircrafts have landed. Comparative experiments show that the CSA-RHC hybrid algorithm is able to obtain an optimal landing sequence and landing times rapidly and effectively. © 2008 IEEE.

关键词： Computational complexity

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Rock magnetism and magnetic anisotropy in folded sills and basaltic flows:A case study of volcanics from the Taimyr Peninsula, Northern Russia

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Chinese Science Bulletin 2008年第5期53卷 759-767页

作者： ZHANG ShuWei J. Harald WALDERHAUG YANG YueJun College of Computer Engineering and Software Taiyuan University of Technology Taiyuan 030024 China Department of Earth Sciences University of Bergen AIl~gaten 415007 Bergen Norway State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Department of Applied Physics Taiyuan University of Technology Taiyuan 030024 China

Magnetic measurements were performed on apparently deformed igneous rocks of 23 sites from the southeastern part of the Taimyr Peninsula. Rock magnetism and reflected light microscopy analyses reveal that fine-grained titanomagnetites up to pure magnetites mainly carry the majority of magnetic fabrics in the sills, and that the slightly coarser Ti-poor or -medium titanomagnetites carry most mag-netic fabrics in the basaltic flows. Magnetic anisotropies were determined by applying anisotropy of low-field magnetic susceptibility (AMS) on 180 unheated samples and 128 samples that had been pre-viously heated to 600°C during a paleomagnetic study to detect heating effects on the anisotropy of magnetic susceptibility (AMS) properties of volcanic rocks. laboratory heating significantly affects anisotropy variations of these igneous rocks corresponding to the mineralogical changes during the heat treatment.

关键词：岩石磁学磁各向异性玄武岩折叠式岩床俄罗斯

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Novel and quick fuzzy rule extraction method

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Kongzhi yu Juece/Control and Decision 2008年第9期23卷 1015-1020页

作者： Chen, Tie-Ming Gong, Rong-Sheng Samuel, H Huang College of Software Engineering Zhejiang University of Technology Hangzhou 310014 China State Key Laboratory of Software Development Environment Beihang University Beijing 100086 China School of Engineering University of Cincinnati Cincinnati 45221 United States

This paper presents a novel method for classification problems. Firstly, entropy is introduced to select the best discretization solution from Chi-merge for each feature to guide grid partition. Afterwards one simple rule is generated from each data point, and the combination of simple rules with the same antecedent yields the consequent of an aggregated rule for each grid. Because grid partition is based on rational discretization, the extracted rules are not only easy to understand but also produce accurate results even without tuning. In addition to quick learning, the method accommodates incremental learning, namely, rules can be updated quickly once new data are obtained. A benchmark case is studied to demonstrate the effectiveness of the proposed method.

关键词： Fuzzy inference

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Dynamic response of submerged floating-tunnel tethers subjected to current

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Gongcheng Lixue/engineering Mechanics 2008年第10期25卷 229-234页

作者： Chen, Jian-Yun Sun, Sheng-Nan Su, Zhi-Bin State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116085 China Civil King Software Technology Co. Ltd. Beijing 100044 China

To study the transversal oscillation response of the tether under vortex-induced vibration and parametric vibration, a nonlinear tether-tube model of submerged floating-tunnels is proposed by the basis of taking the sag of the tether into account. Numerical analysis and solutions are presented by Galerkin method and Runge-Kuta integration method. It may be concluded that the vortex-induced vibration of the tether may excite the parametric vibration of the system;the initial disturbance of the system has a significant effect on the transient amplitude of the tether;the steady-state vibration amplitude of the tether is determined by the vortex-induced vibration;the response under the combined action of vortex-induced vibrations and parametric vibrations is larger than that of any single vibration.

关键词： Galerkin methods

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Wyner-Ziv coding based on signal denoising technique

Wyner-Ziv coding based on signal denoising technique

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2008 5th International Conference on Visual Information engineering (VIE 2008)

作者： Guiguang Ding Xiaodong Shen Key Laboratory for Information System Security Ministry of Education Tsinghua National Laboratory for Information Science and Technology School of Software Tsinghua University Beijing China

In Wyner-Ziv video coding, efficient compression is achieved by exploiting source statistics at the decoder only, which is radically different from conventional video coding. Prior work on this topic has been restricted to a basic framework based on algebraic channel coding principles. In this paper, we propose a novel distributed source coding method based on the signal denoising and channel coding approaches that exploit denoising technique to separate the correlation portion of data which is encoded by channel codec, and then encodes the other portion using entropy codec. Our contributions are mainly as follows: (1) To utilize signal denoising and channel coding techniques to implement distributed source coding, a simple correlation structure between the source and the side information is given. (2) A new distributed source coding framework is proposed. (3) To apply the proposed framework in video coding systems, we propose a novel distributed video coding method. Our experimental results show that, comparing to prior distributed video scheme, the proposed scheme can achieve comparable or even better compression efficiency while coding at the same bit rate.

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On the margin explanation of boosting algorithms

On the margin explanation of boosting algorithms

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21st Annual Conference on Learning Theory, COLT 2008

作者： Wang, Liwei Sugiyama, Masashi Yang, Cheng Zhou, Zhi-Hua Feng, Jufu Key Laboratory of Machine Perception MOE School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Department of Computer Science Tokyo Institute of Technology 2-12-1 O-okayama Meguro-ku Tokyo 152-8552 Japan National Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

Much attention has been paid to the theoretical explanation of the empirical success of AdaBoost. The most influential work is the margin theory, which is essentially an upper bound for the generalization error of any voting classifier in terms of the margin distribution over the training data. However, Breiman raised important questions about the margin explanation by developing a boosting algorithm arc-gv that provably generates a larger minimum margin than AdaBoost. He also gave a sharper bound in terms of the minimum margin, and argued that the minimum margin governs the generalization. In experiments however, arc-gv usually performs worse than Ad-aBoost, putting the margin explanation into serious doubts. In this paper, we try to give a complete answer to Breiman's critique by proving a bound in terms of a new margin measure called Equilibrium margin (Emargin). The Emargin bound is uniformly sharper than Breiman's minimum margin bound. This result suggests that the minimum margin is not crucial for the generalization error. We also show that a large Emargin implies good generalization. Experimental results on benchmark datasets demonstrate that AdaBoost usually has a larger Emargin and a smaller test error than arc-gv, which agrees well with our theory.

关键词： Adaptive boosting

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Group key management method based on tree-shape architecture in Wimax network

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Dongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Southeast University (Natural Science Edition) 2008年第SUPPL. 1期38卷 200-203页

作者： Pan, Shaoming Gu, Yonghao Yang, Yatao Ji, Yichao Department of Electronic Information and Control Engineering Guangxi University of Technology Liuzhou 545006 China Information Security Center State Key Laboratory of Networking and Switching Beijing University of Posts and Telecommunications Beijing 100876 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China

To improve the security and applicable capability of the group key management in 802.16e standard, the traditional group key management mechanism is discussed and the current security solutions for group key management in WiMax is analyzed. By using key tree and one-way function, an improved tree-shape group key management scheme is proposed, and the key updating process during node joining in or leaving Wimax network is also designed. Analysis result shows that, compared with the conventional method of logical key hierarchy (LKH), the proposed scheme has better performance in key storage, key updating and key calculation cost, which provides an effective solution for group key management in Wimax network and has better application value.

关键词： Network security

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A Secure Email Encryption Proxy Based on Identity-Based Cryptography

A Secure Email Encryption Proxy Based on Identity-Based Cryp...

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International Conference on MultiMedia and Information technology, MMIT

作者： Tieming Chen Shilong Ma College of Software Engineering Zhejiang University of Technology Hangzhou China State Key Laboratory of Software Development Environment Beihang University Beijing China

PKI-based security frameworks for Email systems, such as S/MIME, are all good at working for content protects but not efficient because of the high cost for public key certificate management. In others, PGP-based solutions are also popularly studied, but the problem on credential trust management is still in challenging. In this paper, the identity-based encryption mechanism, shortly for IBE, is investigated first. Then, a novel security proxy scheme using IBE is proposed for providing secure Email encryption service. It needs no public key management, and the proxy service can automatically decrypt the encrypted Email contents for the general email users. If only the IDs of the users used for IBE encryption are given, the decryption private key can be requested on-the-demand by the proxy. At last, the security and performance for the proposed system are both discussed.

关键词： Identity-based encryption Cryptography Public key security Electronic mail Programming Protection Costs Content management Postal services

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