Applied Mechanics and Materials Vols. 380-384

Abstract: Many of the characteristics of P2P technology such as decentralization, scalability, robustness, high performance and load balancing are in line with the cloud storage design requirements. In this article, it proposesd a cloud storage model based on P2P technology. This model uses multivariate data server architecture, which can effectively solve the bottleneck problem of centralized cloud storage system. Thereby increasing the cloud storage system performance and the quality of cloud storage services, enhance service reliability. In this article, through researching data consistency algorithm named Paxos and the model systems metadata consistency problem, we improve and optimize Basic Paxos making it applied in the model system.

Abstract: Multi-dimensional Bayesian network classifiers (MBCs) are probabilistic graphical models proposed to solve classification problems. However, in data analysis and preprocessing tasks, one is often confronted with the problem of selecting features from very high dimensional data. To resolve this problem, the covariance analysis and the FastICA algorithm are applied to decrease the dimension and remove redundant information. And then, we only need to construct class subgraph and bridge subgraph of the MBC model with algorithm and mutual information from the processed data, since the new feature variables satisfy independence assumption. The experiment was tested on three benchmark data sets. The theoretically and experimental results show that our method outperforms other state-of-the-art algorithms for multi-dimensional classification in accuracy.

Abstract: According to the problem that the whole data and information is always necessary, using rough set theory as a guide, making some analyses on reduction in knowledge base and information system, this paper propose a general mode structure of reduction. It shows that there are three terms in process of reduction and the most important term is definition and measure of ability.

Abstract: In view of the changeable characteristic of the stray current in subway system, introduced the artificial neural network BP model, using Matlab prepared a program of the BP neural network prediction mode to predict the current drainage cabinet exhaust flow .The simulation results show that the prediction model is simple and efficient to the automatic drainage cabinet drainage strategy in further promote.

Abstract: Identity-based encryption and signature schemes that allow any pair of users to communicate securely and to verify each other's signatures without verifying certificate. A signcryption is a primitive that provides the properties of both digital signatures and encryption schemes in a way that is more efficient than signing and encrypting separately. Proxy signature schemes are a variation of ordinary digital signature scheme that allow a proxy signer to sign messages on behalf of the original singer which proxy signcryption simultaneously fulfill both the functions of signature and encryption in a single step with a lower computational cost than that required by the traditional signature-then-encryption. In this paper, we present identity-based proxy signcryption schemes with lower efficient..

Abstract: As a hot topic in the field of database research, keyword search on data graph has attracted many attentions. However, most of existing works are mainly studied on CPU. An important problem is how to efficiently generate answers for keyword search. In this paper, a parallel approach of keyword search based on interval coding is investigated. The approach includes two main tasks, which are finding root nodes and getting shortest paths from root to keyword nodes. To find root nodes quickly, we adopt a strategy of reachability judging between any two nodes with interval assigned to every node. Meanwhile, aim to speed up finding root nodes and getting shortest paths from root to keyword nodes, we provide data parallel processing for compute-intensive tasks by using graphical processing unit. Experiment results show the high performance of the proposed solution both on CPU and graphical processing unit.

Abstract: Through a comprehensive analysis of using natural language processing in information retrieval, we compared the effects with the various natural language techniques for information retrieval precision in this paper. This is for the tasks of more suitable as well as accurate results of natural language processing.

Abstract: The software design ideas of smart car tracking with camera are described. The following modules are discussed: the main function structure, the initialization of each module, road information collecting module, road information processing module, servo control module and motor control module. The repeated debugging and the real operation of the smart car show that it can accurately collect the road information, control flexibly, run stably, and its velocity reaches 2.2m/s.

Abstract: Recently, a large number of chaotic cryptosystems have been proposed, many of them fundamentally flawed by lack of robustness and security. In this paper, we point out the weakness of a very recent block cipher algorithm which is based on the chaotic Hopfield neural networks with time varying delay and give the improved scheme of it. We provide the chosen plaintext attack to recover the permuted plaintext string, and point out that the encryption speed is not fast enough. It is shown that the dependence on the key, but not on the plaintext, to generate binary sequences of iterating the chaotic map mechanism facilitates leakage of the information and vulnerable been attacked. Based on such a fact, we give the improved scheme to obtain higher security and faster speed.

Abstract: With the continuous expansion of the amount of data resources, network databases are becoming increasingly critical to the development of enterprises. This paper is a comparative analysis and study on the basic information, characteristics and performance of the currently popular network databases, mainly including Oracle, DB2 of IBM, Informix Dynamic Server products, Adaptive Server of Sybase and SQL Server of Software.