Advanced Materials Research Vols. 756-759

Abstract: This paper presents a model based on analysis on interactive users search needs. This model changes from the analysis on user's behavior to the one on search content, which reduces to violate users privacy, and enables users to actively participate in determining the needs of search from the client end in the search engine, in addition to establishment of search demand model based on a large number of user feedback data mining in the search engine subsystem, as a result of higher search precision with less client spending and higher user s participation.

Abstract: This paper draws on the principle of identity-based public key encryption (IBE) system algorithm. A suitable Identity authentication scheme for cloud computing environment is proposed. Security analysis of the scheme is given. The proposed scheme using the bidirectional signature between Client and cloud server has solved the safety verification audit, and realized identity authentication in cloud computing. We provide end-to-end authentication instead of trusted third party, which solve the problem of Key Escrow and improve the efficiency of the management of the identity authentication.

Abstract: In the wireless access technology system, reliable and efficient security algorithm is an important guarantee which realizes the high-speed data transmission of LTE (Long Time evolution). The SNOW 3G was used in LTE for its own advantages for security algorithms. This paper describes the procedure of security. Focus on the principle of confidentiality and integrity algorithms of SNOW 3G , then analyses the performance and gets the test result of this algorithms at last.

Abstract: To make sure a good communication between the terminal and the base station, synchronization is needed between them. The Uplink Time Alignment has been provided in the long term evolution system (TD-LTE), by which uplink synchronization can be maintained in terminals. In this letter, the concrete implementation of the Uplink Time Alignment in MAC sub-layer of terminals and independently adjustment of uplink timing were designed with research of the Uplink Time Alignment and detailed analysis of the specific applications of Timing Advance Command in the terminal. The proposed implementation can be applied for the development of test instrumentation and TD-LTE ratio frequency conformance.

Abstract: Delay Tolerant Networks (DTN) has been widely used in challenge networks as an emerging network architecture. Among all studies , routing mechanism is the key problem in DTN. Because of high latency and low data rate, the traditional network routing algorithm can not apply to DTN. This paper proposed a DTN routing mechanism based on area dipartition. The mechanism divided the space into several regions, and calculated the probability of occurrence of each node in each region to determine data transfer path according to the probability. Finally, the simulation results show that the mechanism can significantly enhance the message delivery probability and reduce the packet loss rate.

Abstract: Ship parallel collaborative database is the important carrier for the ship designer, Its safety has been a more concerned hot issue among the field of ship design. This paper analyzes the ship parallel collaborative database security needs, proposed RBAC role-based control mechanism.

Abstract: A solution based on PLC remote I/O is put forward for the production information collection and management of the automobile assembly line required. SIEMENS S7-200, S7-300PLC and IPC, LED large screen are integrated into an information system which accomplishes various information display of help application on each station, failure alarm for stopping the line, TAKT in the assembly line, periodical production plan and information display of the current completion and production information. Thus the failure can be immediately cleaned and the production status can be dynamically controlled. Through long-term running the system, it has shown that the system can timely acquire data, display them and store complete information.

Abstract: This paper first introduces the MIMO-OFDM (Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) system model, and then studies several classical channel estimation algorithms: LS (Least Square) algorithm, LMMSE (Liner Minimum Mean-Square Error) algorithms and SVD-LMMSE (Singular value decomposition) algorithm. Finally, based on the DCT transform domain channel estimation, the original SVD-LMMSE algorithm has been improved. Theoretical analysis and simulation results show that: The improved SVD-LMMSE algorithm not only can reduce the complexity of the implementation, but also has more superior performance.

Abstract: The cloud computing can greatly reduce the cost of computing, but is unable to ensure either the integrality or the confidentiality of data and calculation. Therefore, this paper considers of the safety of cloud computing, combining the thought of abstract algebra group theory in modern algebra, puts forward TCCPoGT (trusted cloud computing platform based on group theory) that designs in many different respects,such as general structure, public key cryptosystems and node management,etc. The analysis results show that the platform TCCPoGT can insure service security.

Abstract: The Rapid development of cloud computing impels the new situation of information technology services in foreign language teaching in universities, and brings more quality requirements to subject librarians in universities. The teaching database of English reading in universities combines image, audio, video, text, animation and interactive contents for teaching to create a fresh, vivid, interesting English learning environment. The paper proposes the implementation strategies of university English reading teaching datebase construction and the cloud service model according to the concept of cloud computing; It thinks that the subject librarians should supply personalized services for the readers, at the same time, they should also strive to be cloud librarians.