Applied Mechanics and Materials Vols. 336-338

Abstract: Aiming at the problem of traditional windows need manual operation, intelligent windows system based on power line carrier (PLC) and GPRS wireless communication technology was designed. The system used PLC technology realize the establishment of the internal network; Used varieties of sensors as peripheral detection devices and data acquisition equipment, transmitted collected data to central controller through the power line; Used ARM9 embedded processor S3C2440A as center controller; Used GTM900C module as interface between internal network and external network, passed data and forwarded control commands. Terminal PC used LabVIEW graphical programming language, it could receive GPRS signal coming from Internet according to the fixed IP address and port number, and sent monitoring commands to the fixed IP address. This paper listed out hardware block diagram and software implementation process. The design concept can spread to other intelligent households. The experimental results suggest that the intelligent windows have implemented smart windproof, rainproof, anti-theft, fire prevention and prevent gas poisoning. It provided a good solution for the design of smart home.

Abstract: With the rapid development of science and technology, the current spectrum resources can not simply cope with the high-load wireless networks transmission. In addition, because the use of spectrum resources can not be fully maximize the overload load phenomenon, which leads to the waste of resources and loss of the spectrum, the existing overall spectrum resources are not adequate utilization and its utilization can not be improved. Obviously, in order to meet the growing demand for Internet and wireless communications, we must address the low rate of utilization of spectrum resources To this end, it is proposed to use the spectrum resources in cognitive radio drainage techniques, cognitive radio node to perceive the change of radio spectrum resources, and thus connected in the most appropriate timing and spectral integration, the effect of radio data transmission, and adequately addressed the problem of the spectrum resource low utilization. This thesis is based on the in-depth analysis of cognitive radio technology to understand the routing protocol in wireless cross-layer data transmission, and then discuss the relevant characteristics of the AODV routing protocol, and base on the AODV, the routing protocol uses in the analysis of the radio network organization based on the proposed to the possibility of cognitive radio.

Abstract: In this paper, a new four-dimensional hyperchaotic system is studied. The basic dynamic behaviors of the system are analyzed by numerical simulation. The bound of the chaotic system is estimated. In addition, a constructive theorem is proposed for nonlinear generalized synchronization related to the chaotic system. Example is presented for illustrating our methods and an application in secure communication is demonstrated.

Abstract: The mobile grids bring some additional features into the grid, such as mobility, energy-constrained, etc. And the task scheduling becomes a more challenge thing. We propose a mobile grid task scheduling model considering the mobility of both user and resource, and the resource energy consumption. Through analyzing the architecture of mobile grid, a mathematical model is built to calculate the average distance between the resource and Base Station (BS). Then, it can decide which mobile grid the mobile devices are apt to stay in, which can deal with the mobility of mobile devices. On the other hand, the resource energy consumption is also considered, which ensure that the resources have enough energy to finish the task. As a result, the task can be assigned to the best resources in the suitable mobile grids. The failures may happen in the task scheduling because of many unpredictable factors. So the fault-tolerance scheme based on the notion of replication is proposed.

Abstract: To shield heterogeneous and distribution of system and improve the efficiency of development, middleware technology has been successfully applied to the traditional distributed system. But in the wireless sensor network environment, traditional middleware technology is facing enormous challenges such as dynamic environment, network asymmetry, frequent disconnection, limited resources, and wide diversity of context. Therefore, it is important to design the universal middleware for massively heterogeneous wireless sensors. It can improve the system performance and efficiency and provide effective extension and expansion for traditional middleware. In this paper, we introduce the system structure of the universal wireless middleware platform, which is divided into infrastructure middleware and application service middleware. Meanwhile the key technologies of the middleware platform for wireless computing environment are analyzed.

Abstract: This paper proposes a new phase tracking algorithm for the 802.11a system. Since this system illuminates the basic structure of 802.11a system, and introduces the OFDM frame generation principle based the transmitter, phase error estimation and channel estimation. On the basis of this, this paper presents a phase tracking scheme based on adaptive Kalman filter, and then simulates the process based on 802.11a system. The result indicates that the BER has been improved because of this adaptive phase tracking scheme.

Abstract: Naturally, for the mountain mapping, the communication system's power is limited, As a matter of fact, the stations should be built as high as possible in order to eliminate the terrain shielding and radiate to the farther areas, however the number of users or other aspects also counts, In this paper, we introduced new methods to locate the modified location for the base stations in the mountain areas, and with this method, we use less stations to cover the most areas in the given situation. For a random mountain terrain. the coverage rate of this model is as high as 95.1%.

Abstract: Aiming at the rigorous requirements of space optical communication device to laser pointing accuracy, a laser emission system based on the fast steering mirror is designed. The closed-loop control of the laser pointing can be realized by using the fast steering mirror with the characteristics of high-precision and high-bandwidth and combining the target recognition technology. The laser emission experimental system is built in the laboratory. The experimental results show that the laser pointing control accuracy can be greatly improved by the combination of fast steering mirror control and target recognition technology. Laser pointing accuracy is within 20 seconds to reach the sub-micro-radian magnitude.

Abstract: The main purpose of this paper is to study the implementation of load shedding under the condition of IEC61850 (Communication Networks and Systems in Substations) communication exchange in the power system. The strategy of load shedding with IEC61850 GOOSE (Generic Object Oriented Substation Event) message relies on fast transmission of the signal to shed unstable regions for maintaining system safety. The current strategy for load shedding in the substation is to use hardwire and dispatch solutions to implement related applications of load shedding. For integrating protective relays in substations, IEC61850 GOOSE schemes can customize both a ring and a star construct based on TCP/IP Ethernet to have flexible dispatch of smart grid solutions. The functions of relay integrated with the GOOSE message play important roles to implement peer to peer communication to accomplish the load shedding strategy.

Abstract: Wireless multimedia sensor network routing protocols based on ant colony optimization algorithm (ACOQoS) is proposed. Based on the existing routing protocol design concept, and the actual needs of QoS from each network layer of wireless multimedia sensor networks, the protocols use the Agent collection method to select cluster head node, from the perspective of the balance network load. And maximize the network lifetime by balanced use of energy of the whole network.