Applied Mechanics and Materials Vols. 385-386

Abstract: The overall design was explained from three aspects about object monitoring and management system for satellite location. The functions of information comprehensive process, situation integrated display, information terminal were proposed. Then the system which interconnected center control node and terminal nodes was developed by integrating communication technology, GIS technology, GPS technology, and Beidou navigation technology, thus it realized the bidirectional information interaction between all the nodes. Based on MapGIS, the objects dynamical monitoring and management were implemented on the tactical situation map, as well the key technologies for the system were described.

Abstract: With the comparison of wireless positioning technology such as Wi-Fi, ZigBee, GPS, this paper presents an outdoor personnel positioning system based on GPS. It is composed of electronic wristbands (used for detainees), handsets (used for supervisors) and monitoring software of the host computer. In order to improve the positioning accuracy and reduce power consumption of the system, high-precision GPS chips and low power microcontroller chips are applied. Handsets can exchange data with electronic wristbands through self-prepared communication protocol. It also can work out the distance through a precise latitude and longitude distance algorithm. Finally, the monitoring software will reproduce personnel routes in Google Earth. The system can achieve the positioning of fixed groups and moving groups, which is suitable for the detention center to supervise, escort or chase detainees.

Abstract: This paper presents the background of PON (Passive Optical Network), introduces the powerful communication design and simulating software which named Optisystem, show the PON(Passive Optical Network) theory and structure, designs the PON fiber link which has 1310nm uplink wavelength and 1490nm downlink wavelength and then analyses the models performance. In the software, we set up a rate of 1Gbps model of PON by using the component in the Optisystem. Through calculating the model, the document gets the spectrum figure of the simulate fiber link, and analyses the parameter, such as spectrum character, Q factor, eye diagram and BER, the result verified the validity and practicable of the models design, makes the result that the initial character fiber link cant meet the demand of optical communication, so changing the transmission distance to 10 km , transmitter power to-1dBm, meeting and obtaining the basic requirements of the system performance, after that the paper comparing the coding between none return to zero (NRZ) and return to zero (RZ) encoded mode, the eye diagram analyzer component show that NRZ code is better than RZ code, in the end of the paper there is the conclusion.

Abstract: Based on the problems of traditional broadcast system such as complexity wiring and low efficiency, this paper presents a design scheme of intelligent addressable broadcast system which takes the advantages of Zigbee and frequency modulation (FM) technologies. This system adopts a cluster topology structure with a master and numerous of broadcast nodes. The network management and system control is realized by Zigbee. The audio signal is transmitted via FM broadcast. Besides, we realized the upper computer software design based on Visual C. The practical test shows that audio quality and system efficiency are both greatly enhanced, and the broadcast system is low-cost, low-power and low-complexity.

Abstract: PTV is a kind of digital television service developed by telecommunication operation business, which provides multicast, VOD and time-shifted, as well as a variety of value-added applications. The broadcasting quality of the IPTV program will determine the popularization of this service. This article mainly analyzes the broadcasting mode, monitors the key parameters and standards of IPTV program. It layouts the IPTV program broadcasting monitoring system, and defines the monitoring function to specific equipment to guide the development implementation of the system.

Abstract: Digital TV refers to a system which transforms the traditional analog signal into digital for processing, transmitting and receiving. In order to protect the interests of the operators and ensure the development of digital television, CAS (Conditional Access System) of digital TV uses various kinds of digital technology through the scrambling process of the program, so that only the authorized users can watch the scrambled programs. This paper mainly introduces the principle of CAS in current DTV, as well as elaborates the realization example of the CA running on the STi5105 chip platform and the detailed process from transplant to descrambling successfully.

Abstract: Firstly, through deeply analyzing the security threats that exist in the PON, this paper proposes a technical idea which integrates high-efficiency subcarrier multiplexed quantum key distribution into PON-SDG communication system. Secondly, we conduct theoretical calculation for the configuration parameters of PON and verify the feasibility of the technology. Finally, the concrete implementation flow-diagram and the generation process of the session key are given .The research results can provide the theoretical reference for building the secure and efficient SDG.

Abstract: In this paper, a new family of binary sequences of period is proposed, where and . The presented family takes 7-valued correlation values , , , , , and . For and , it is proved that the proposed sequence family has linear spans , where l = 2, 3, 4, 5, 6, 7, and the distribution of linear span of sequences in is determined.

Abstract: It's one of the effective channels for short-distance wireless communications through stratum in underground mines on emergency communications. The geologic structure is complex in mines, in practical environments. It means there is a considerable difference in conductance property and channel characteristics. In order to realize effective communication through stratum, its necessary to explore and study underground signal transmission by establishing mathematical model of underground signal propagation characteristics based on the theory of constant current field and simulating the mathematical model with MATLAB. We established a simulation model of underground communication channel physics experiments and obtained the amplitude frequency characteristic of the channel, with which we can get the error comparison between theory and test.

Abstract: There are some problems in the traditional face recognition: too sensitive to light, its classification is too simple, hard to apply to distributed system. For these problems, this paper does three work: used HOG feature in the face recognition, that improved it get more steady feature in different type of light; putting forward NSMD (Nearest Sample Max Distance), it try to find some partly best classifications to unite one strong classification, so the classification hyperplane can be more far from the sample boundary; finally the algorithms of this paper specially the one-to-one design mode are adapt to MapReduce, so its feasible to own the advantages of distributed system (expansively safety...). With the experiment analysis, the work gets their goals: HOG feature can be adapt to different lights, NSMD can get better rate of identification, the MapReduce algorithms can get fine speed-up ratio.