Applied Mechanics and Materials Vol. 610

Abstract: With the development of Internet technology and the increasing popularity of the Internet, the amount of information data of enterprises increased sharply. How to avoid unexpected data corruption and to improve the system of data security and data recovery capabilities has been the focus of attention of users and enterprises. Regular backups of the database is to restore the data the easiest and most effective guarantee method and is an effective measure database administrators to manage data. This paper proposes a plan of database scheduled tasks based on Linux environment. This plan can be timed to export the database, be sent automatically to a secure backup mailbox and complete the regular backup of the database finally.

Abstract: The dimensioning is a time-consuming job in engineering drawing. So, it introduced an automatic dimensioning method to improve the efficiency of drawing dimensioning. Firstly, it used the functions which provided by Pro/Engineer to extract the parts dimension information from part’s feature. Then, in order to avoid the overlap in dimensioning, it stratified the dimensioning zones. Finally, it constructed a hash function to determine the location of each layer. The method has been implemented in an engineering drawing dimensioning system based on Pro/E, and successfully applied to the dimensioning in engineering drawing of CNC gantry milling machine parts.

Abstract: By using mapping knowledge domain, this paper analyzes the literature from 2005 to 2013 of user behavior in network community, the results show that with the development of the Internet and the maturity of the social media, the research in this field is increasing. Now, the papers mainly focus on the study of the user behavior, virtual community and online community, and the chief methods are structural equation model and social network analysis, also, they have a deep analyze on trust as an influence factor. First, to have an overall understanding of the research situation, this paper analyzes three aspects as follow: the information of the papers, the author of the papers and the research institutions, second, it focuses on the research frontier and the cited references.

Abstract: Wireless communication technology has been widely applied in People's Daily life. However, limited spectrum resources and low spectrum utilization of spectrum resources shortage is proposed. In this paper, a cognitive function of backoff algorithm (CR-BOA) is raised. This algorithm depending on the degree of congestion channel adaptive adjustment the size of the backoff value .This algorithm greatly improves the performance of the network, and reduces the problems of delay caused by the spectrum resource scarcity. Finally, use the OPNET simulation software, the results show that the end-to-end delay and the packet loss rate are reduced.

Abstract: Though Grid Delivery Services (GDSs) can promote Quality of Service (QoS) in Content Delivery Networks (CDNs), some of them may degrade the performance of the client computers by consuming the network resources. The worst part of GDSs is that some of them are registered as system services and executed automatically when the operating system boots up. Since GDSs are not classified as malware, it is extremely hard to detect them automatically even when the user wants to remove them. This paper proposes an automatic method to detect GDSs by monitoring the network usage of all the processes. We include empirical evidence to indicate this approach is effective even though it adopts an extremely simple approach.

Abstract: Learning the multiplication tables is extremely important to the elementary and middle school students, it is one of the pillars to understand mathematics, but sometimes learning this content becomes something mechanical and exhausting, making it difficult for the students to understand, especially those with Attention Deficit Hyperactivity Disorder (ADHD). Therefore a virtual environment was developed to teach the multiplication tables to the elementary and middle school students with ADHD. All good programming practices were followed. The validation was performed by educators and computer specialists with excellent results. For the next stage of the research a validation with the students will be performed.

Abstract: This paper demonstrates methods to recognize 3D designed features for virtual environments and apply them to Virtual assembly. STEP is a standard of Product data Exchange for interfacing different design systems, but it cannot be used as input for virtual environments. In order to use feature data in virtual assembly environments, main data source from a STEP file should be recognized and features should be re-built. First, Attributed Adjacency Graph (AAG) is used to analyze and express the boundary representation; second, a feature-tree of a part is constructed; third, using the AAG and feature-tree as inputs, we analyze and extract of features with a feature recognition algorithm; finally, various levels of detail of object geometric shapes is built and expressed in XML for virtual assembly applications.

Abstract: In this paper, a novel pentacle-based visualization strategy is used to generate numerical feature for network visiting data. A 20-dimensional feature set is built for the 5-class classifier so as to establish an accurate intrusion detection system. By integrating the proposed 20 new features with the built-in feature sets, which consists of 41 features, the new intrusion detection system achieves an accuracy of 99.588%.

Abstract: STK is the important tool of satellite simulation and analysis, it can be intuitive and vivid reflects the state of satellite orbit. The STKX component allows user code to respond by writing incident response and control the user to the operation of the GUI interface STK components, in order to enhance the application of interactive ability. In this paper, through the application of the STKX component, and the design of Qt Chinese interface, realize the function of orbit dynamics simulation, 2D and 3D images and satellite images show function; To realize the Two-way exchange of information. Convenient man-machine interface and Chinese interface implements the intuitive and mutual assistance, and operating process of the simulation.

Abstract: the security of database system as the core component of data storage has been increasingly important. Effective audit of the database system can reduce the potential security risk. Practical database audit system should not affect the operation of the existing system which uses audited database. This paper presents and implements a multi-protocol database audit system based on bypass mode, and has a detailed description of the function of each module and the interface between them. This paper designs a detailed database audit policy to achieve effective audit. In the second half of this paper, we focus on the implementation of the key technologies which contain Zero-copy and flow table. Keywords- database; zero-copy; flow-table;policy; audit