• ETRI Journal
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• v.28 no.1
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• pp.119-122
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• 2006

We present an intelligent optical switching structure based on our lambda-group model along with a working scheme that can provide a distinctive approach for dividing complicated traffic into specific tunnels for better optical performance and grooming efficiency. Both the results and figures from our experiments show that the particular channel partition not only helps in reducing ports significantly, but also improves the average signal-to-noise ratio of the wavelength channel and the blocking performance for dynamic connection requests.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.3
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• pp.119-129
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• 2016

This paper presents an integrated navigation system for accurate navigation solution-based safety and convenience services in the vehicular augmented reality (AR)-head up display (HUD) system. For lane-level guidance service, especially, an accurate navigation system is essential. To achieve this, an inertial navigation system (INS)/global positioning system (GPS)/vision/digital map (IGVM) integrated navigation system has been developing. In this paper, the concept of the integrated navigation system is introduced and is implemented based on a multi-model switching filter and vehicle status decided by using the GPS data and inertial measurement unit (IMU) measurements. The performance of the implemented navigation system is verified experimentally.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.43.2-43.2
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• 2010

Following the success of detecting fringes on KVN (Korean VLBI Network), a phase referencing observation is currently planned in order to achieve a better sensitivity in mm-VLBI. The high frequency observation ($\geq$ 22 GHz), wide bandwidths (~512 MHz) and high speed data recording (~1 Gbps, Mark5B) will result in resolution and sensitivity improvement on KVN. In particular, two powerful techniques of VLBI phase correction by fast-antenna switching and multi-frequency phase referencing are also introduced in KVN, hoping to resolve the problem of atmospheric delay errors which degrade the coherence significantly. In this study, we have compared the expected performance of phase referencing between fast antenna switching and multi-frequency phase referencing and discussed the essential condition and postulates of phase referencing for KVN.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.8 no.1
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• pp.38-42
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• 1983

The characteristic of a Tunnel Diode(TD) is approximated by the summation of two exponential terms, obtained from the haracteristic curves displayed on the curve tracer. Using this result, static characteristic of a TD pair was plotted by a computer programming. From these static characteristic curves, the triggering behavior of TC pair multi-vibrators was described graphically. Two stable characteristics were analyzed by piecewise linear Method. Theoritical switching Theoritical switching times of a TD pair flip-flop(F-F) circuits were compared with experimental results.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.539-540
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• 2002

A self-discharge in multi-EEFLs and CCFLs has been found to provide a high luminance and efficiency. With a fast rising and falling times of $2{mu}s$, and the peak voltage over 1.6KV, the self-discharge occurs in EEFLs and CCFLs driven by a full bridge switching inverter. Particularly in CCFLs connected with a typical value of ballast capacitance, a self-discharge follows by the main discharge when the voltage falls to the ground.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.536-538
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• 2002

Various types of switching inverters such as a full-bridge, a half bridge, a push-pull, and a multi-vibrator, are introduced for multi-lamps backlighting with EEFLs and CCFLs. Synchronizing the phase between voltage and current waves, a high luminance and a high efficiency have been achieved.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.171-173
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• 2002

This paper describes the open frame type high power density switching converter. It is based on active clamp forward converter with synchronous rectifier, and packaged by using the open frame and multi-layer printed circuit board (PCB) techniques to achieve the high power density. Furthermore, windings of transformer and inductor are also realized by multi-layer PCB so that it achieves the higher power density. Through the experiment on the proto-type converter of 50[W], it is confirmed that power density of $50[W/in^3]$ and maximum efficiency of over 91 [%] are obtained.

• Management Science and Financial Engineering
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• v.19 no.2
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• pp.49-53
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• 2013

A Markov-chain Monte Carlo sampling algorithm samples a new point around the latest sample due to the Markov property, which prevents it from sampling from multi-modal distributions since the corresponding chain often fails to search entire support of the target distribution. In this paper, to overcome this problem, mode switching scheme is applied to the conventional MCMC algorithms. The algorithm separates the reducible Markov chain into several mutually exclusive classes and use mode switching scheme to increase mixing rate. Simulation results are given to illustrate the algorithm with promising results.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.5 no.2
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• pp.94-98
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• 1987

Multi-Valued(MV) sequential logic circuits are proposed which are free from HAZARD. In this paper, HAZARD is classified Function and Logic HAZARD, and MV switching function in which they are eliminated is described. Also, the basic MV memory elements which can be realized without HAZARD are presented, so that suggest the realizability in the large-scale MV logic system based on these elements.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2123-2125
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• 2000

A multi-gap pseudospark is high power switching with a wide dynamical voltage range. The pseudospark system has been operated at the voltage of 5$\sim$20 kV and the pressure range of 35$\sim$80 mtorr. The switching current of the pseudospark switch was measured as 106 kA for 3 gaps. 124 kA for 4 gaps, 120 kA for 5 gaps. The current duration is about 0.9${\mu}s$ in each multi-gap switch. To obtain the characteristics of the switch, this paper describes the results of tests.