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Woo, Chun-Hee;Park, Gun-Sik
- The Transactions of the Korean Institute of Electrical Engineers P
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- v.55 no.2
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- pp.62-66
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- 2006
This thesis focuses on the design of control schemes for highly efficient BLDC motor drive applications using drives with output capacity of 1Hp. The control system was designed and implemented on a PIC micro-controller and applied to an electric vehicle as a viable replacement to the existing a high phase induction motor that is currently being used for these low cost, small traction drive applications. This paper for the brushless drive research has shown the optimization of the drive system for improved drive design and switching techniques that can improve the entire drive system efficiency for electric vehicle both large and small traction applications using sinusoidal PWM techniques for synthesizing the AC waveforms needed to control these traction drives. In addition, Numerical simulation was conducted to evaluate the performance of designed BLDC Motor using MotorPro simulator.
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Lee, Yong-Wook
- Journal of Sensor Science and Technology
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- v.20 no.4
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- pp.230-233
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- 2011
In this paper, highly-efficient optical gating in a junction device based on vanadium dioxide($VO_2$) thin film grown by a sol-gel method was investigated as a gate terminal of a three-terminal device using infrared light with a wavelength of ~1554.6 nm. Due to the photoinduced phase transition, the threshold voltage of the $VO_2$ junction device, at which the device current abruptly jumps, could be tuned with a sensitivity of ~96.5 V/W by adjusting the optical power of the infrared light directly illuminating the device. Compared with the tuning efficiency of the previous device fabricated using $VO_2$ thin film deposited by a pulsed laser deposition method, the threshold voltage of this device could be tuned by ~76.8 % at an illumination power of ~39.8 mW resulting in a tuning efficiency of ~1.930 %/mW, which is ~4.9 times larger than the previous device.
https://doi.org/10.5369/JSST.2011.20.4.230 인용 PDF KSCI

Sin, Bong-Kee
- Journal of Korea Multimedia Society
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- v.11 no.6
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- pp.807-815
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- 2008
A simple efficient method of spotting and recognizing hand gestures in video is presented using a network of hidden Markov models and dynamic programming search algorithm. The description starts from designing a set of isolated trajectory models which are stochastic and robust enough to characterize highly variable patterns like human motion, handwriting, and speech. Those models are interconnected to form a single big network termed a spotting network or a spotter that models a continuous stream of gestures and non-gestures as well. The inference over the model is based on dynamic programming. The proposed model is highly efficient and can readily be extended to a variety of recurrent pattern recognition tasks. The test result without any engineering has shown the potential for practical application. At the end of the paper we add some related experimental result that has been obtained using a different model - dynamic Bayesian network - which is also a type of stochastic model.
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Hwang Kwang-Il;Eom Doo-Seop;Hur Kyeong
- The Journal of Korean Institute of Communications and Information Sciences
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- v.31 no.9B
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- pp.792-802
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- 2006
In this paper, we propose an energy-efficient proactive data dissemination protocol with relatively low delay to cope well with highly mobile sink environments in sensor networks. In order for a dissemination tree to continuously pursue a dynamic sink, we exploit two novel algorithms: forward sink advertisement and distributed fast recovery. In our protocol, the tree is shared with the other slave sinks so that we call it Dynamic Shared Tree (DST) protocol. DST can conserve considerable amount of energy despite maintaining robust connection from all sources to sinks, since tree maintenance of DST is accomplished by just distributed local exchanges. In addition, since the DST is a kindof sink-oriented tree, each source on the DST disseminates data with lower delay along the tree and it also facilitates in-network processing. Through simulations, it is shown that the presented DST is considerably energy-efficient, robust protocol with low delay compared to Directed Diffusion, TTDD, and SEAD, in highly mobile sink environment.
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