Applied Mechanics and Materials Vols. 719-720

Abstract: In Peer-to-Peer (P2P) Video-on-Demand (VoD) streaming systems, supporting free VCR operations is challenging. Prefetching is a good way to improve user experience of VCR interactivity. But most existing P2P VoD prefetching schemes are proposed aimed at those popular videos with large amount of log data, without considering the situation that the videos are unpopular or the popular videos are in their initial phase of release. In this situation, these schemes cannot support user VCR interactivity very well. To address this issue, we propose a new optimized prefetching scheme, called Hybrid Anchor Scheme (HAS), in which fixed anchors and dynamic anchors are merged together. The dynamic anchors are generated based on association rule and segments popularity. Through combining the way of sequential prefetching according to weight of segments and the way of several rounds prefetching, we implement HAS effectively. Extensive simulations validate the proposed prefetching scheme provide shorter seeking latency compared to other prefetching schemes.

Abstract: In this paper, we present the end-to-end performance of a dual-hop amplify-and-forward variablegain relaying system over Mixture Gamma distribution. Novel closed-form expressions for the probability density function and the moment-generation function of the end-to-end Signal-to-noise ratio (SNR) are derived. Moreover, the average symbol error rate, the average SNR and the average capacity are found based on the above new expressions, respectively. These expressions are more simple and accuracy than the previous ones obtained by using generalized-K (KG) distribution. Finally, numerical and simulation results are shown to verify the accuracy of the analytical results.

Abstract: The self-organizing nature of its architecture of wireless sensor networks (WSNs) introduce unique challenges for privacy preservation of data. This paper analyzes the cluster-based private data aggregation protocol (CPDA), and proposes a privacy protection protocol based on hierarchical cluster. We firstly reorganize nodes in cluster according to the logic structure of binary-tree in which each node transmits slice data instead of the full one. And then, we establish the hierarchical privacy tree to manage the group of keys, which purpose is privacy protection in case of data aggregation.

Abstract: We study the high clustering model of K. Klemm and V.M. Eguiliuz [1]. The basic idea is the growing networks based on a finite memory of the nodes. Our main contributions are as follows: based on the high clustering model, we investigate analytically that it does generate a power-law degree distribution and give the exact solution from the perspective of Markov chain. And the degree exponent varying is depend on the parameters α and m.

Abstract: Finding a delay constrained least-cost path in a directed graph is a fundamental issue for quality of service provisioning in communication networks. Recently Feng and Turkay proposed a hybrid algorithm which uses a heuristic approach to boost the average performance of a well known approximation algorithm. In this paper we provide extensive simulation results to show that the hybrid algorithm runs significantly faster than the approximation algorithm, often by one or two orders of magnitude.

Abstract: As Intelligent Transportation System (ITS) grows increasingly in size and complexity, the issues on how to improve interoperability and the performance of processing massive data become more critical. This paper proposes a new three-dimensional layered network architecture called Local Dynamic Map/Multimedia/Management (LDM³) to address these issues. In LDM³, the three-dimensional architecture consists of the information fusion layer newly introduced, as well as the application layer and transport layer. The primitive mechanism defined in the architecture improves the efficiency of the communication of network elements in such heterogeneous network system. By using the standardized format of message and data, the application systems can get desired information pushed by information fusion layer, instead of processing data from all kinds of sensors. This mechanism improves the effectiveness of the whole system significantly by avoiding duplicate work on different application systems. Meanwhile, the workload and the hardware requirement for application systems are relieved. We apply LDM³ in the demonstration project for traffic Internet Of Things (IOT) in Jiangsu province. The result shows LDM³ is an effective and efficient solution for ITS.

Abstract: Chaotic encryption algorithm is simple, fast speed, no more memory, and suitable for using in wireless sensor networks (WSNs). This paper points out the defect of the iteration encryption and the fact that it’s vulnerable to chosen-plaintext attack. In this paper, a feedback chaotic encryption algorithm is proposed to improve the program that not only effectively avoid the defects, but maintain all the advantages of chaotic encryption algorithm. The improved algorithm is more suitable for small data encryption used in WSNs.

Abstract: Network technology accelerates the development of educational information, campus portal building is considered as an important part of it in every university, almost all information of teaching and research appeared on the web. Meanwhile, the utilization rate of some websites was lower in university, information was updated slowly, information classifications were complex and not standardized on a platform. They didn’t emphasis on using and sharing but building and developing, and this phenomenon was widespread. So the paper proposed a decision tree model for score sorting information based on C5.0 algorithm, setting up a statistical model for data mining by adding a line weight value for portal information. Finally, the results verify the correctness and science of the model by giving an example.

Abstract: Constructing a hybrid wireless sensor networks comprising a mix of static sensors and mobile sensors can achieve a balance between improving coverage and reducing the cost of the network. In order to achieve high network coverage, mobile sensor move from a small to a big size of coverage hole in the hybrid wireless sensor networks. Due to the energy of the mobile sensor is limited, how to reduce the moving distance of the mobile sensor and reduce the energy consumption in the process of moving is a very important issue. This paper proposes a distributed minimum cost matching algorithm (DMMA) to redeploy mobile sensor, which can make the level of network coverage to meet the requirement of the environment, while effectively reducing the number of sensors. In our method, static sensors detect coverage hole by Voronoi diagrams, coverage holing sensors and mobile sensors by using DMMA to excellently heal the large coverage holes. Simulation results show that our method can effectively improve the coverage rate of the WSNs, while save the energy of mobile sensors.

Abstract: With the development of our society, electronic devices, such as laptops, tablets and mobile phones become increasingly widespread. An accompanying problem of this is the increase of theft aimed at these devices. Even though the proper administration and policy plays an important role to mitigate this crime, they still occur ubiquitously. Therefore, for the sake of eliminating this crime, not only the aspects of administration, policy and legislation should be enhanced, but also the corresponding techniques need to be reinforced. In fact, technology plays a dominant role in preventing crimes. In this paper, a conceptual design of an anti-theft alarm system based on antenna array and wave transmission models will be introduced piece by piece. By implementing a series of electronic components embedded into a protecting wireless network, the location of the protected object can be detected in real time. Once a theft occurs, the computation center will instantaneously obtain the data related to this behavior and assess its authorization and then determine to report or ignore it. This alarm system is specifically suitable for use in public places, for example, libraries, cafes, and holiday villages.