Advanced Materials Research Vols. 846-847

Abstract: Using feature selection and neural networks to experiment the data, then we bring a warning model of user complaints. It is the core that using the known information of network index sample to analyze and discriminate. First, the training samples need to be extract, because there are too many features in training data will have an adverse impact on machine learning classification algorithm. Using extraction method to explore the feature subset with feature, feature subset is a set of feature vectors, then the feature vectors are input into the probability neural network prediction, find out the best features quantum set. This model can be achieved using the MATLAB software, and it is operational, and it can be extended to the network quality assessment and monitoring practice.

Abstract: A improved genetic algorithm is proposed based on a new fitness function in allusion to the problem that the traditional genetic algorithm is not fully consider the knowledge of the problem itself.The improved genetic algorithm is used to analyze the fault feature , to extract the fault and remove redundant characteristic parameters for the fault classification and calculation.The diagnosis example shows that the method has faster convergence speed and can be effective for fault identification.

Abstract: Distribution automation is an effective method to realize fault detection and localization. It is not suitable for use in the comprehensive promotion in the distribution network because of the high investment and maintenance requirements. It proposes the monitoring system design principle firstly. The distribution line monitoring system based on internet of things technology is practical and of high scalability. It solves the problems in detection of single phase grounding fault, the terminal power supply and communication network. This system records peak current when zero sequence voltage a communication terminal monitors is greater than a certain value. A variety of power supply by solar energy, lithium battery backup and terminal itself can provide the power supply and wireless communication power supply. The system is suitable and practical for application in the distribution line.

Abstract: LXI, which is generally recognized as the new generation of instrument bus technology, not only has developed rapidly in the field of test and measurement, but also has a vast potential for future development. At present, the LXI trigger requires the clock synchronization precision to reach a sub microsecond level or even higher one. Therefore, in order to meet this accuracy requirement, a scheme based on the embedded Linux and IEEE 1588 protocol is proposed in this paper on the basis of studying LXI so as to realize high accurate clock synchronization. This scheme acquires hardware timestamp by utilizing PHY chip DP83640 and realizes PTP hardware clock driving based on Linux. A synchronization test with Agilent B LXI trigger box under the current condition is conducted and about 100ns of synchronization precision can be reached when connected with cable directly. The result demonstrates the feasibility of the scheme and that the clock synchronization precision can reach a nanosecond level.

Abstract: A cascading failure model for multi-layered networks is established using the Coupled Map Lattices (CML) method, the invulnerability of multi-layered network under random attacks and intentional attacks is investigated. The simulation results show that compared with isolated networks, multi-layered networks are more fragile and dont exhibit the invulnerability to suppress cascading failures under random attacks. Furthermore, we find that decreasing the inter-layer coupling strength or enhancing the inner-layer coupling strength can significantly improve the invulnerability of the multi-layered networks to resist cascading failures.

Abstract: Compared with traditional GPCR, there are three differences in the new GPCR-D: 1) GPCR-D is a topology and position based routing protocol. 2) It can detect dynamically the network density and establish the local areas with high node density, where vehicles speed is limited and topology changes slowly. Therefore, we adopt shortest path algorithm aimed at delivering packets speedily. While outside the local areas, topology changes rapidly, so greedy forwarding is used to avoid restoring and maintaining links frequently. Thus GPCR-D makes full use of their respective advantages. 3) The repair strategy of GPCR-D selects the neighbor whose direction is closest to destination in the neighbor table as the next forwarding hop. The simulation shows that GPCR-D works more effectively than GPCR in terms of average delivery success rate and end-to-end time delay.

Abstract: WSN comprise of large number of sensor nodes with different hardware abilities and functions. Due to the limited memory resources and energy constraints, complex security algorithms cannot be used in sensor networks. Therefore, it is necessary to well balance between the security level and the associated energy consumption overhead to mitigate the security risks. In this paper, we present A Novel Key Management Scheme for Cluster Based Wireless Sensors Networks (NKMS). The security analysis demonstrates that NKMS is an effective solution to the key management of cluster based wireless sensor networks.

Abstract: One of the key issues in wireless sensor networks is to design efficient and secure group key agreement scheme. The Merkle identity tree is firstly introduced, then an efficient scheme based on Merkle identity tree is proposed. With this scheme, the direct and secure communications between any subgroups without retransmission could be implemented. The security of the scheme can be assured under the complexity assumptions. The detailed analysis of the initialization procedure, subgroup key agreement procedure, group communication procedure and rekeying procedure when membership changes, including joining and leaving, shows that the scheme is efficient in computation and communication cost.

Abstract: Designing efficient and reliable group key agreement scheme is one of the key issues in wireless sensor networks. An authenticated group key agreement scheme is proposed, which based on ternary tree and short signature using bilinear pairings on elliptic curve. In the proposed scheme, five authenticated two-party and three-party key agreement algorithms are adopted. The security of the group key agreement scheme can be assured under the complexity assumptions. The analysis of the initial agreement procedure, rekeying procedure when membership changes, includes joining and leaving, shows that the scheme is efficient in computation and communication cost.

Abstract: In order to solve the problem, which is "the traditional fire alarm system is only used to detect a particular physical or chemical signal of the fire, moreover, false alarm and failure alarm can occur easily. We apply multi-sensor composite detection technology and wireless communication technology in the fire detection and alarm system,and design an intelligence distributed wireless fire detection alarm system, which is mainly based on STM32 control chip.