Applied Mechanics and Materials Vols. 543-547

Abstract: Based on the theory of cloud computing, this paper uses Hadoop distributed computing framework and the MapReduce programming model, designs and implements a campus cloud computing system for processing huge amounts of data. The system uses a three-layer architecture, has the flexibility to expand the scale, low development cost and ease of operation, reduces the difficulty of parallel programming and has the ability to efficiently handle massive data analysis and processing.

Abstract: Rate control has significant impact on the video coding. However, the conventional rate control algorithm in the latest video coding standard H.264 without take into account the human visual system and result in video quality fluctuation. To address this problem, we propose a novel rate control algorithm for H.264/AVC considering frame activity. First, a method is proposed to detect the scene change in frames of video sequences. Second, bit allocation to frame is related to the frame activity which is calculated on the local motion activity and scene change in frames. And in the MB level, the number of bits allocated to each MB is determined by its local motion activity. Experimental results show that the proposed rate control algorithm can increase average PSNR by 0.9137 comparisons with the JVT-G012, and reduces the bit-rate error by up to 0.06%.

Abstract: The massive data in Data centers network will be frequently accessed massive datasets for cloud services, which will lead to some new requirements and becomes an important issue for interconnection topology and data management in cloud computing. According to the cost-effective, the paper proposes a new interconnection network MyHeawood for cloud computing. MyHeawood is constructed by small switches and servers with dual-port NIC according to recursive method. The data placement strategy in MyHeawood is a hashing algorithm based on the family of hash functions. MyHeawood uses three replicas strategy base on master copy, which is allocated in different sub layer to improve the reliability of data.

Abstract: Based on the algorithms of negative selection and clone selection, this paper sets out to propose a new design of internet worm detector, inspired by the biological immune system. It describes the working and algorithms of immune systems against Internet worms and comes up with diagrams.

Abstract: This paper mainly discusses the integration of the enterprises application system based on the Web Services technology. The Web Services technology can realize the system application integration in the enterprise internal system and the different enterprise application systems,it is universal, platform independent, and language independent. set. This makes Web Services to become a new generation integration technology of the enterprise application integration in the Internet environment .

Abstract: In this paper, Information System is introduced firstly, and then combining practical examples during our development of IS, on the basis of the establishment of the decision-making oriented query subsystem in large Information System, the query subsystem in the Information System based on decision-making is designed, moreover, the query subsystem is implemented following the query processing principle.

Abstract: With the development of computer technology, the performance of hardware is no longer the primary problem that influences the performance of the web server. Just improving the hardware processing speed of the web server is invalid in practical applications, so the performance of the web server should be improved in the software layer. The improving methods focus on the followings: In the aspect of the network IO, the EPOLL structure is used. The EPOLL structure can not only deal with mass network connections, but also have a better performance for processing network data. Those improvements all enhance the throughput of the system effectively. In the aspect of the hard disk IO, the asynchronous IO is used to replace the synchronous blocking IO, so the hard disk IO and other requisitions can be processed simultaneously. Besides, the hard disk IO requisitions are processed by kernel instead of application layer, so the number of concurrent request and the usage effectiveness of CPU can be improved at the same time. This means the processing capacity of the web server can be improved consequently. At last, aiming at moving data effectively from file to the network interface, the zero-copy technology is used to optimize especially. This helps the improvement of the web servers business processing capacity a lot. Above methods are used to put forward a high performance web server model which is based on the asynchronous IO and the zero-copy technology. The web server model is realized at the foundation of the analysis of several traditional web server models. Those lay the groundwork for the further study of a high performance web server model which is more practical and has more abundant functions.

Abstract: Testing is of great significance for the safe and reliable running of a large-scale software system. Starting from analysis on the weakness of Combinatorial Testing techniques when they are applied to large-scale software testing, a test model is given which is more in line with the actual characteristics, and some theorems about software input-output space reduction are also proven based on the model. It is proved that the input-output space of a large-scale software can be significantly reduced by proper decomposition according to the relationships between different software modules and the correlations between input factors and output factors. The results of this paper lay a theoretical foundation to simplify the testing of large-scale software systems.

Abstract: Cloud computing is one of the most significant shifts in recent years. Cloud computing development brings the revolution to todays business models. The topic of cloud computing has become a hot topic in the ICT industry. Virtualization techniques as a symbol of cloud computing evolve fast. For example, KVM is a typical virtualization solution. However, its security issues aroused by the characteristic of open source may hinder subscriber to employ it. In order to address current security issues in KVM virtualization environment, this paper deeply analyzes KVM hypervisor and VM security problems, proposes KVM-based virtualization security framework, and discusses its related security mechanisms. Also, Linux OS built-in security mechanisms including SELinux and cgroups are discussed. By investigate Hypervisor, VM, and external management tools connection security issues, this open source-based virtualization ecosystem can be protected better than ever.

Abstract: In accordance with the object-oriented design principles, the flight simulation platform of each function is modular and hierarchical. The 1 Pool 2 Pieces 4 Layers software framework is proposed, using VC++ features to abstract all the replaceable modules to the same class, realizing rapid conversion of a variety of aircraft and different tests, to achieve reconfigurable. The realistic flight dynamics model considering wind disturbance is established, and with F-16 model as an example has conducted digital simulation and visual simulation. The results show that the platform has good maneuverability and fidelity, and provides reliable basis for aircraft design.