Applied Mechanics and Materials Vols. 401-403

Abstract: Twitter has emerged as an ideal platform both for conversation and substantive real-time events, growing considerable concerns whether tweets are credible or not. In this paper, we concentrate on investigating the credibility perceptions of events which would generate abundant activity and significant interconnection on Twitter. We present several methods for crawling tweets set from Twitter according to certain rules. Furthermore, we conduct various experiments for assessing credibility, in which we list affluent categories of features relevant to determining credibility and prominent algorithms to improve the effectiveness for assessing credibility. And then we bring forward some existing imperfection of previous research on information credibility and further look into the future work benefit for assessing credibility precisely.

Abstract: Aimed to the security and privacy issues which restrict the construction and development of the Internet of Things, a WSN-oriented key agreement protocol in the Internet of Things ( IOT) has been proposed . Trust management was introduced the security mechanism of IOT, the use of bilinear pairing technology, the identity-based key agreement was realized. Using the protocol not only can effectively prevent attacks from outside the network and can recognize the abnormal nodes which were captured or lapsed efficacy. Thus it can reduce communication with abnormal nodes to improve network security, extending the lifetime of the network. The distributed self-organizing key negotiation process without credible third-party management can enhance the survivability of IOT, and the network has a good scalability.

Abstract: This paper designs a data protection scheme for high-capacity mobile storage device which encrypts the data and keeps the data from being stolen and modified. Coupled with the use of SM1 cryptographic algorithm, the identity authentication mechanism has also been used, which secure the safety of the system.

Abstract: There are some common problems, such as low sampling efficiency and large amount of calculation, in mobile localization algorithm based on Monte Carlo localization (MCL) in wireless sensor networks. To improve these issues, an enhanced MCL algorithm is proposed. The algorithm uses the continuity of the nodes movement to predict the area where the unknown node may reach, constructs high posteriori density distribution area, adds the corresponding weights to the sample points which fall in different areas, and filters the sample points again by using the position relations between the unknown node and its one-hop neighbors which include anchor nodes and ordinary nodes. Simulation results show that the localization accuracy of the algorithm is superior to the traditional localization algorithm. Especially when the anchor node density is lower or the unknown nodes speed is higher, the algorithm has higher location accuracy.

Abstract: For the same controlled process, different controller is radically different in control effect. Aimed at the puzzle of being difficult to select the controller for the incompatibility among control performance index, the paper proposed a sort of improved PSO algorithm. Based on the construction of objective function in multi-performance index parameter, the algorithm could quickly search and converge to control parameter in global optimal extremum corresponded to each controller and single out the controller through performance comparison excellently. In the paper, it took the controller selection of wastewater treatment system as an example, designed the algorithm of multi-modal HSIC controller of DO parameter, made the experiment of system simulation, and the simulation demonstrated that the HSIC controller could be stronger in robustness and better in dynamical and steady control quality compared with improved PID controller. The research result shows that it is reasonable and applicable to optimize selection of controller.

Abstract: The library database design needs to accord certain rules, in relational database, this rule is paradigm. Paradigm is in line with a certain level of relational schema collections. Relational database relationship must meet certain requirements, namely to meet the different paradigms. At present, there are six kinds of relationship database paradigm: the first normal form (1NF), the second normal form (2NF), the third normal form (3NF), BC normal form (BCNF), the fourth normal form (4NF), the fifth normal form (5NF) and the sixth Normal Form (6NF). The 1NF is the minimum paradigm for requirement. Basing on the 1NF, further meeting more requirements is the 2NF and a higher level paradigm, in practical design application, you only need to reach the 3NF.

Abstract: As network environment is becoming more and more complex, it is difficult for students to understand and master the complex and abstract network concepts. A virtual learning tool named Cisco Packet Tracer has been introduced into the classroom teaching, which provides the virtual configuration environment as real one. This article presents the features of the virtual simulation tool, and the configuration example for mini practice project, which can inspire students creativity. It makes teaching and learning computer network much easier than traditional teaching method.

Abstract: The core idea of modern logistics is to create value at the lowest cost. To achieve this goal enterprise must integrate logistics resources in society. Previous technologies can not help logistics industry achieve this goal without appropriate business model and cloud computing can give a hand. Cloud computing can effectively reduce IT investment and risk, can get IT service in less investment and shorter cycle to improve enterprises responsiveness to business changes. This article proposed the logical model and function modules of integrated logistics resources service platform. On this base it constructed the architecture of integrated logistics resources service platform based on cloud computing. Cloud computing architecture consisting of infrastructure layer, application layer and service provider layer was set up. This model has expedited new market and new services for logistics

Abstract: Aimed at the puzzle that it is heavy in energy consumption and not better in water quality to water supply engineering resulted in inappropriate control strategy, the paper explored the energy saving strategy and control mechanism of water supply system. In the paper, it discussed the cybernetics characteristic of water supply process, proposed the intelligence-fusion based control strategy and the energy saving executing strategy, and analyzed the control model of water supply purifying process and the control algorithm of constant pressure control system. The comparative research of simulation demonstrated that the proposed strategy would be better than conventional PID control method. The simulation results show that the strategy combined intelligence-fusion based control with speed control by inverter has better application prospect.

Abstract: This paper deals with the decay of hydrogen-air proton exchange membrane fuel cell (PEMFC) stack, which has been used for three years, installing a 5kW fuel cell stack in a sightseeing bus to do the experiment, including road test and bench test. The results indicate that the hydrogen-air fuel cell stack power performance declines a lot, whose power conspicuously drops from 5kW to nearly 2.5kW, compared with that of a new one. There are many reasons of its decline, such as, proton membrane penetration and electrode destruction etc. It proves that the stack needs reasonable care and maintenance; otherwise, it tends to be easily exhaustive and thus greatly increases costs.