Xingfa Shen

Fuzzy control of LED tunnel lighting and energy conservation

Abstract Current highway tunnel lighting control systems are often manually controlled, resulting in significant energy waste. This article designs a fuzzy control algorithm for tunnel lighting energy control systems. The system uses LED (Light Emitting Diode) lighting, so the fuzzy control algorithm is designed for LED lights. The traffic and the natural illumination level are used as parameters in the intelligent lighting control algorithm. This system has been deployed in the Lengshui tunnel on the 49th provincial highway of Zhejiang province and operated for more than six months. The performance results show that the energy conservation system provides sufficient lighting levels for traffic safety with significant energy conservation.

Energy-efficient and localized lossy data aggregation in asynchronous sensor networks†

SUMMARY n nIn wireless sensor networks, most data aggregation scheduling methods let all nodes aggregate data in every time instance. It is not energy efficient and practical because of link unreliability and data redundancy. This paper proposes a lossy data aggregation (LDA) scheme to reduce traffic and save energy. LDA selects partial child nodes to sample data at partial time slots and allows estimated aggregation at parent nodes or a root in a network. We firstly consider that all nodes sample data synchronously and find that the error between the real value of a physical parameter and that measured by LDA is bounded respectively with and without link unreliability. Detailed analysis is given on error bound when a confidence level is previously assigned to the root by a newly designed algorithm. Thus, each parent can determine the minimum number of child nodes needed to achieve its assigned confidence level. We then analyze a probability to bound the error with a confidence level previously assigned to the root when all nodes sample data asynchronously. An algorithm then is designed to implement our data aggregation under asynchronization. Finally, we implement our experiment on the basis of real test-beds to prove that the scheme can save more energy than an existing algorithm for node selection, Distributive Online Greedy (DOG). Copyright

Research on Experimental Platform and Methods for the Course Interface and Communication

Along with the rapid development of computer technologies, teaching contents and experimental environment of the traditional course ldquoInterface and Communicationrdquo have being enormously changing. How to establish the experimental teaching system under Windowspsila protected mode is always the emphasis and difficulty for teaching reform of the course ldquoInterface and Communicationrdquo. The paper analyses the three methods of accessing computer hardware in Windowspsila protected mode. While these methods are applied to experimental teaching of the course ldquoInterface and Communicationrdquo in modern PCs, the advantages, disadvantages and feasibility are pointed out. Then the experiment design and implementing scheme are put forward.