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This paper presents a single-switch LED driver based on Class-E converter with digital control. The working frequency of switch can reach the 500kHz, which can decrease the volume of system and improve the difficulty of design of LED driver system. Based on Extended Describing Functions (EDF) model analysis method, utilizing the soft switching character of Class-E, a digital control method is applied to improve the efficiency and decrease the volume of system in high frequency working state. Buck-Boost circuit is selected as the power factor correction (PFC) cell, Class-E is used as the DC-DC converter to realize the energy transmit. By applying the digital control, a 100W prototype of LED driver is presented. The experimental results certify the validity of proposed LED driver with digital control. The power factor (PF) can reach the 0.99 and efficiency of system can reach 92% at the rated state.

Point-of-care testing (POCT) for an infectious diseases is the prerequisite to control of the disease and limitation of its spread. A microfluidic chip for detection and classification of four strains of Ebola virus was developed and evaluated. This assay was based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) and specific primers for Ebola Zaire virus, Ebola Sudan virus, Ebola Tai Forest virus and Ebola Bundibugyo virus were designed. The sensitivity of the microfluidic chip was under 103 copies per milliliter, as determined by ten repeated tests. This assay is unique in its ability to enable diagnosis of the Ebola infections and simultaneous typing of Ebola virus on a single chip. It offers short reaction time, ease of use and high specificity. These features should enable POCT in remote area during outbreaks of Ebola virus.

Artificial bee colony (ABC) algorithm is a promising evolutionary algorithm inspired by the foraging behaviour of honey bee swarm, which has obtained satisfactory solutions in diverse applications. However, the basic ABC often demonstrates insufficient exploitation capability in some cases. To address this concerning issue, a chaotic artificial bee colony with elite opposition-based learning strategy (CEOABC) is proposed in this paper. During the search process, CEOABC employs the chaotic local search to promote the exploitation ability. Moreover, the elite opposition-based learning strategy is utilised to exploit the potential information of the exhausted solution. Experimental results compared with several ABC variants show that CEOABC is a competitive approach for global optimisation.

One of the problems of current fuzzy recognition for power quality (PQ) disturbances is that the conclusion part of fuzzy rules is commonly fuzzy variable needing defuzzification, and the parameters of membership function are always determined by trial-and-error method. To solve this problem, this paper presents a new recognition method of power quality disturbances based on T-S fuzzy logic. On the basis of features extracted from disturbances by generalized S-transform (ST). The T-S fuzzy inference mechanism is proposed in this paper, of which equalized universe method is used to determine the membership function parameters and universe division. The Recognition results of simulation and experimental data show the effectiveness of the proposed method.

Nowadays, disaster occurs more and more frequently, which brings huge losses to the society. Presented a GIS based emergency broadcast system (GIS-EBS), to provide rapid, accurate information to the public, can reduce the people's losses maximum. Different from the traditional radio data system (RDS), by adding broadcasting terminal control instruction on the FM signal, GIS-EBS extended the RDS protocol, which can control each radio terminal's state. And through the extended RDS protocol, GIS-EBS can broadcast and release the emergency information to the right place and the people most in need in the shortest time.

The impulse performances of stator winding insulation system for 10kV ac explosion-proof motor with the type of protection increased safety are studied in this paper. The measurements of impulse voltage waveforms along one stator winding from the phase terminal to neutral had been carried out. The calculation of electric field on the air gap and surface of stator end-winding were calculated. The impulse voltage and its gradient distribution along the stress gradient coating of end-windings were also calculated. The results showed that the impulse voltage may cause a high electric field or gradient localized on the surface of stator end-winding. The characteristic of stress gradient coating suitable for the impulse voltage was optimized and designed also.

With the increasing scale of the power system, the smart substations are becoming widely used. Substation need to complete the function of information collection, status monitoring, controlling and regulation etc. to meet the requirement of automation and intelligence. Therefore the communication of smart substation has some real-time requirements. Fieldbus for the substation can make a network connection between substations. To meet the real-time requirement, the applications of industrial Ethernet are getting widespread. EtherCAT is a kind of real-time industrial Ethernet. It has the features of high transmission rate, flexible topology type, low cost and good security, etc. Hence EtherCAT is a technology which is very suitable to the application of substations. This paper is a research of network construction in the smart substation, and gives an analysis of features of industrial Ethernet EtherCAT, especially its real-time feature.

The traditional test system can no longer meet the rapid development of modern servo system. So a new kind of automatic test system is designed in this paper. The overall network structure of the system is based on C/S and B/S mixed mode and is designed in layers, which consists of advanced test instruments, user-friendly virtual interface, database server, LAN clients and web server. Database technology is applied to help storing and managing the massive test data. The connection between LabVIEW and database is realized by using the Database Connectivity Toolkit. The local clients can monitor the real-time interface with the help of DataSocket technology. The web page interface is published by web server, which can be accessed and browsed easily by the remote experts. After analyzing the test results, the recommendations offered by the experts can help improve the performance of the servo system effectively.

In recent years, with the proposal of strong and smart grid, the reliability requirements of the Electric Power Data Network are getting higher and higher. Based on the background, this paper proposes a novel Electric Power Data Network for the smart grid. After that a comparative analysis on the information congestion degree is provided between the novel Electric Power Data Network based on artificial spider web topology and the traditional Electric Power Data Network based on the star topology. The results show that the Electric Power Data Network using the artificial spider web topology has a higher reliability.

To enhance the reliability of narrowband PLC (Power Line Communication) in low-voltage network, inspired by the structure and invulnerability of spider web, a new PLC network model is proposed in this paper. The characteristics of the model and the transformational process of low-voltage distribution network from physical topology to artificially spider web logical topology are thoroughly discussed. New networking algorithm and route-reconstruction algorithm are put forward. A two-state Markov model is used to simulate a terminal node and the time-delay characteristic of the new algorithm is analyzed by modeling. Based on Opnet 14.5, simulation and comparison are conducted, which prove that the new network model has advantages in improving the communication reliability of PLC network.

For application requirements about Commercial network management, this paper discussed the feasibility for GIS to improve commercial network management, and used GIS technology to improve the traditional application models of business network management, According to these models, developed a GIS-based commercial network management systems, and the practical application of the system show that the system can improve network management efficiency and scientific and has important value in applications.

As an important and essential natural resource to human development, forest has an extremely important significance for the sustainable socio-economic development. This paper primarily carries out the overall design of forest fire prevention information system based on GIS. Posterior, C# and C++ language are used on .NET platform, based on ArcEngine Geography Information Component Library, Janus UI Controls interface component library for the development and implementation of the system. Finally, application has been achieved in the urban forest of Jiangxi Province by this fire prevention system. The application results show that the system has the functions of forest fire prevention video surveillance, fire danger rating prediction, fire auxiliary command, and post-disaster damage assessment, nearest search facility, path analysis, and fire records management and so on. Which can greatly improve the work efficiency, benefit and information level of fire safety.

Modern city is the main bearing body to learn, live, work, entertainment for people. City safety not only directly impacts on people's life quality and work efficiency, but also indirectly restricts to cities themselves harmonious and sustainable development. This paper primarily introduces the significance of GIS-based city safety information system development; posteriorly designs the framework structure, function modules and database composition; and then develops system completely under computer hardware and software environment needed such as operating system is Windows XP, system development platform Visual Studio 2005, database platform SQL Server 2000, development language Visual C# 2005, components ArcObjects of Geographic Information System software ArcGIS; ultimately successfully applies it to an urban safety management work. The result shows it does meet the needs of urban safety daily management, so its development and application have practical significance and application value.

Power line communication (PLC) is the unique effective way to connect digital electronic ballast for HPS lamp into communication network without any new wiring in the new public lighting management system. The PLC network with a large scale of digital electronic ballasts in such industrial environment is always vulnerable and is liable to be destroyed in logical layer. To improve the reliability of the PLC network, the channel properties and the running characteristics of digital electronic ballast that affect the reliability of the PLC network are analyzed, and the possible ways in MAC layer to enhance the reliability of the PLC network are investigated. According to the investigation results, a novel low cost simplified self-organization algorithm in MAC layer suitable for practical engineering is proposed and the logical connectivity of the PLC network is automatically kept. The performance of the algorithm is evaluated analytically and experimentally.

Power line communication (PLC) plays an important role in such no-new-wiring applications as digital HPS ballast remote management in new public lighting system. PLC data link especially with a large scale of ballast nodes is liable to be destroyed because of the dynamic channel properties. The reasons that lead to the failure of data link, the corresponding methods to enhance the reliability of PLC network are investigated, and the hybrid dynamic topology of the PLC network is studied, which is based on self-organizing algorithm in MAC layer with improved fault-tolerance ability. According to the study results, a low cost TDMA-like MAC protocol suitable for the hybrid PLC network initialized by self-organization algorithm is proposed and the performance is analyzed by M/D/1 model compared with polling. The general round robin cycle duration of PLC networks with hybrid structure that interested to remote monitor and control system is also presented.