• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.2 s.332
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• pp.15-22
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• 2005

Using the existing analog circuits, required resistor matching and Poly-Si TFT characteristics are investigated for the implementation of analog circuits to be integrated on System-on-Glass. Matching requirements on resistor values, threshold voltage and mobility of poly-Si TFT are derived as a function of the resolution of display system. Also, the effective mobility of poly-Si TFT required for the realization of source driver is analyzed for various panel sizes.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.7
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• pp.673-678
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• 2013

Driving gear units can be affected by various problems, including those associated with external or internal defects in the bearing, problems with the lubricant oil, high-loading of the railway, and frequent impacts generated by rail joints. Temperature monitoring is a basic method in diagnosing abnormal conditions in the reduction gear and other components. This paper describes a new wireless monitoring system for the temperature diagnosis of abnormal conditions of the reduction gear. Integrated circuit (IC)-type temperature sensors were installed in the reduction gear box of a high-speed railway car. The temperature data from the reduction gear were acquired and analyzed in situ during high-speed rail operation. Analysis of these data was used to alert the driver and/or maintenance personnel when problems occurred.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.290-293
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• 2013

Due to vehicle personal injury accident does not, and to analyze the cause and prevention of a variety of devices and technologies are coming out. Among other things, representative of the black box, and rear camera. Despite these advances in technology, and vehicle human injuries continue to occur. The reason for this is that the children, the negligence of the driver or the vehicle is in reverse when a person suddenly passed the back of the vehicle, or the rear of the existing detection system is properly detected was unable to. Therefore, In this paper, we want to design a black box to reveal the cause of the accident, using Kinect to prevent accidents, rear-view camera and rear integrated black box system.

• Journal of Drive and Control
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• v.17 no.3
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• pp.9-14
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• 2020

A special purpose machine with two manipulators and quadruped crawler system is being developed to work at disaster sites where it is intended to quickly respond in the initial stages after the event. In this study, a terrain recognition module is developed so that the above special purpose machine can quickly obtain ground information to help choose its path while recognizing objects in its way, this is intended to enhance the remote driver's limited situational awareness. Terrain recognition modules were developed for two tasks (real-time path guidance, precision terrain measurements). The real-time path guidance analyzes terrain and obstacles while moving, while the precision terrain measurement feature provides more accurate terrain information by precisely measuring the ground in front of the vehicle while stationary. In this study, an air-cooled sensor protection module was developed so that the terrain recognition module can continue its vital tasks in the event of exposure to foreign substances, including scattered dust, mist and rainfall, as well as high temperatures.

• ETRI Journal
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• v.37 no.6
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• pp.1165-1175
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• 2015

This paper presents an advanced sensorless permanent magnet (PM) brushless motor controller integrated circuit (IC) employing an automatic lead-angle compensator. The proposed IC is composed of not only a sensorless sine-wave motor controller but also an isolated gate-driver and current self-sensing circuit. The fabricated IC operates in sensorless mode using a position estimator based on a sliding mode observer and an open-loop start-up. For high efficiency PM brushless motor driving, an automatic lead-angle control algorithm is employed, which improves the efficiency of a PM brushless motor system by tracking the minimum copper loss under various load and speed conditions. The fabricated IC is evaluated experimentally using a commercial 200 W PM brushless motor and power switches. The proposed IC is successfully operated without any additional sensors, and the proposed algorithm maintains the minimum current and maximum system efficiency under $0N{\cdot}m$ to $0.8N{\cdot}m$ load conditions. The proposed IC is a feasible sensorless speed controller for various applications with a wide range of load and speed conditions.

• ETRI Journal
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• v.30 no.4
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• pp.526-534
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• 2008

This paper presents a fully integrated 0.13 ${\mu}m$ CMOS MB-OFDM UWB transmitter chain (mode 1). The proposed transmitter consists of a low-pass filter, a variable gain amplifier, a voltage-to-current converter, an I/Q up-mixer, a differential-to-single-ended converter, a driver amplifier, and a transmit/receive (T/R) switch. The proposed T/R switch shows an insertion loss of less than 1.5 dB and a Tx/Rx port isolation of more than 27 dB over a 3 GHz to 5 GHz frequency range. All RF/analog circuits have been designed to achieve high linearity and wide bandwidth. The proposed transmitter is implemented using IBM 0.13 ${\mu}m$ CMOS technology. The fabricated transmitter shows a -3 dB bandwidth of 550 MHz at each sub-band center frequency with gain flatness less than 1.5 dB. It also shows a power gain of 0.5 dB, a maximum output power level of 0 dBm, and output IP3 of +9.3 dBm. It consumes a total of 54 mA from a 1.5 V supply.

• Journal of Home Health Care Nursing
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• v.25 no.2
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• pp.127-138
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• 2018

Purpose: This study aimed to provide an overview of the present status of start-up literacy. Methods: The study selected literature from KoreaMed, RISS (Research Information Sharing Service), KISS (Korean studies Information Service System), KISTI (Korea Institute of Science and Technology Information), Ovid-MEDLINE (Medical Literature Analysis and Retrieval System Online), Embase, and Cochrane Library DB. Start-up curricula were collected from the homepage of nursing schools in Korea and the USA. Their contents were searched using Massive Open Online Course (MOOC) platforms; KOCW, K-MOOC, and Coursera. Results: Fifteen articles were selected through a systematic literature review. The main themes of nursing start-up were "driver," "barrier," "required competency," and "importance of education." The courses contained business planning, finance, marketing, leadership, and entrepreneurship. The main contents of MOOCs were similar. Conclusion: The results indicate the necessity to develop multi-scope nursing start-up education programs. Nursing start-up models integrated with appropriate business knowledge and skills in health care settings are needed. This study can be used as a guideline to design start-up education programs in nursing.

• Journal of Power Electronics
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• v.11 no.3
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• pp.271-278
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• 2011

This paper presents a LLC resonant controller IC for secondary side control without external active devices to achieve low profile and low cost LED back light units. A gate driving transformer is adopted to isolate the primary side and the secondary side instead of an opto-coupler. A new integrated dimming circuitry is proposed to improve the dynamic current control characteristic and the current density of a LED for the brightness modulation of a large screen LCD. A dual-slope clock generator is proposed to overcome the frequency error due to the under shoot in conventional approaches. This chip is fabricated using 0.35 ${\mu}m$ BCD technology and the die size is $2{\times}2\;mm^2$. The frequency range of the clock generator is from 50 kHz to 500 kHz and the range of the dead time is from 50 ns to 2.2 ${\mu}s$. The efficiency of the LED driving circuit is 97 % and the current consumption is 40 mA for a 100 kHz operation frequency from a 15 V supply voltage.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.64-71
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• 2006

In this paper, a uniform speed controller for an ultrasonic rotary motor is developed using the phase-difference method. The phase difference method uses traveling waves to drive the ultrasonic motor. The traveling waves are obtained by adding two standing waves that have a different phase to each other. A compact phase-difference driver system is designed and integrated by combining VCO(Voltage Controlled Oscillator) and phase shifter. Theoretically the relationship between the phase difference in time and the rotational speed of the ultrasonic motor is sine function, which is verified by experiments. Then a series of experiments under various loading conditions are conducted to characterize the motor's performance that is the relationship between the speed and torque. Proportional-integral control is adopted for the uniform speed control. The proportional control unit calculates the compensating phase-difference using the rotating speed which is measured by an encoder and fed back. Integral control is used to eliminate steady-state errors. Differential control for reducing overshoot is not used since the response of ultrasonic motor is prompt due to its low inertia and friction-driving characteristics. The developed controller demonstrates reasonable performance overcoming disturbing torque and the changes in material properties due to continuous usage.

• Journal of Auto-vehicle Safety Association
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• v.10 no.4
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• pp.40-49
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• 2018

Currently, a lot of researches about high risk test scenarios for autonomous vehicle and advanced driver assistance systems have been carried out to evaluate driving safety. This study proposes new type of test scenario that evaluate the driving safety for autonomous vehicle by reconstructing accident database of national automotive sampling system crashworthiness data system (NASS-CDS). NASS-CDS has a lot of detailed accident data in real fields, but there is no data of accurate velocity in accident moments. So in order to propose scenario generation method from accident database, we try to reconstruct accident moment from accident sketch diagram. At the same step, we propose an accident of occurrence frequency which is based on accident codes and road shapes. The reconstruction paths from accident database are integrated into evaluation of simulation environment. Our proposed methods and processor are applied to MILS (Model In the Loop Simulation) and VILS (Vehicle In the Loop Simulation) test environments. In this paper, a reasonable method of accident reconstruction typology for autonomous vehicle evaluation of feasibility is proposed.