• 센서학회지
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• 제25권5호
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• pp.303-309
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• 2016

In this paper, we introduce a new method for controlling the illumination of LEDs in visible light communication (VLC) by changing the duty cycle of Manchester code. When VLC data were transmitted in Manchester code, the average optical power of the LEDs was proportional to the duty cycle. In experiments, we controlled the illumination of a $3{\times}3$ LED array from 10% to 90% of its peak value by changing the duty cycle of the Manchester code. The synchronizing clocks required for encoding and decoding the Manchester code were supplied by pulse generators that were connected to a 220 V power line. All pulse generators made the same pulses with a repetition frequency of 120 Hz, and they were synchronized with the full-wave rectified voltage of the power line. This scheme is a very simple and useful method for constructing indoor wireless sensor networks using LED light.

• 한국재난정보학회 논문집
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• 제6권2호
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• pp.87-106
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• 2010

This research focused on the effect of the GIS, uIT, and RS based smart disaster systems. Ubiquitous IT strongly involved in intelligent analysis for the natural disasters. Remote sensing technologies, such as hyper-spectral imaging, MODIS, LiDAR, Radar, and optical imaging processes, can contribute many means of investigation for the natural and unnatural problems in the atmosphere, hydrosphere, and lithosphere. Recent IT trends guides abundant smart solutions, such as automatic sensing using USN, RFID, and wireless communication devices. Smart monitoring systems using intelligent LBSs will produce many ways of checking, processes, and controls for the human safeties. In results, u-smart GIS, uIT, and RS based disaster systems must be using ubiquitous IT involved smart systems using intelligent GIS methods.

• 한국전자파학회논문지
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• 제11권2호
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• pp.242-251
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• 2000

Ka 및 mm파 대역에서의 강우감쇠는 무선회선설계에 큰 영향을 미친다. 본 논문에서는 전반적인 기초가 되는 Mie 산란이론을 이용하여 국내환경에 적합한 강우감쇠를 추정하기 위해 중요한 요소인 빗방울 크기분포를 여러 자료를 비교하여 분석하였고. 일반화된 식을 통해 수치해석적 접근을 시도함으로써 각 파라미터별 강우감 쇠에 미치는 정도를 분석하여 이론적으로 국내 강우환경에서의 강우감쇠를 추정하기 위한 근거를 제공하고자 하였다.

• Structural Engineering and Mechanics
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• 제42권5호
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• pp.747-760
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• 2012

In today's online social structure, people with electronic devices or network have been closely related to whether any of the activities, work, school, etc., is related to electronic devices, intelligent robot, and network control. The best mobility and the first rich media of these products as smart phones, smart phones rise rapidly in recent years, high speed processing performance and high free way to install software, deeply loved by many business people. However, not only for smart phone business aspects of the use, but also can engage in education of the teachers or the students are learning a great help. This study construct OCR-assisted learning software written by the JAVA made, and the installation is provided by the Android mobile phone users.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.653-658
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• 2003

This study is represented a method to give connect to optical cable from accident site and reviewed the method to transmission a moving image to control centre by real time, following the study of image transmission method in copper cable section where is a main line of railroad communication. Concept of network is studied to use cable and equipment effectively, and it's also reviewed technology of digital image transmission system and image evaluation methods, in spite of the pixel of camera and monitor resolution determine quality of image when moving image transferring by point to point. In addition, this study is reviewed checks and considerations of image transmission equipment (codec) with various transmission methods in room test, and then examined and analyzed wire/wireless combined transmission methods at wayside.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2002년도 동계연구발표회 논문개요집
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• pp.12-12
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• 2002

We present the new jaw tracking system that utilizes five degrees of freedom of head and lower jaw. The proposed method does not disturb the physiology because the system does not need to fix magnetic field sensors or clutch on the patient's body or mouth. The impact of this result goes beyond the conventional optical and magnetic tracking system of jaw movement [1][2]. Position accuracy within 1mm and reasonable cost is necessary for practical use of the jaw tracking system. (omitted)

• 한국통신학회논문지
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• 제40권2호
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• pp.310-312
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• 2015

본 논문은 SIM/SM에 자승 결합기법을 적용한 시스템을 제안한다. 실외 환경에서 SIM/SM은 대기의 격변에 의한 성능 저하가 발생한다. 자승 결합기법은 수신부에서 다수의 광검출기를 배치하고, 수신 된 각 신호를 제곱하여 합성함으로 격변에 의한 성능 저하를 감소시킬 수 있다. 다양한 주파수 효율에서 광검출기의 수를 증가시킬수록 성능 이득이 커지며, 격변의 세기가 강할수록 더욱 효과적인 성능 개선이 가능함을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.171-176
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• 2004

An electric power efficiency of electrodeless fluorescent lamp has big relative propertye of gas in lamp, gas pressure, lamp formation, ingredients of magnetic substance and shape and action frequency etc. We used magnetic substance that open self-examination material of electrodeless fluorescent lamp antenna. Ferrite that is used in this experiment was Mn-Zn type. Coill turn was changed from 13th to 15th turn to recognize brightness change of lamp by winding number. Optical equipment that used in an experiment was used to measure brightness (LS-100). When an electrodeless fluorescent lamp was made using and T company's PE22, was it showed the highest brightness. As number of winding is increased the brightness increased, and starting characteristic became good.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.560-562
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• 2010

오늘날 LED 조명 시스템은 전력을 적게 소비하고 형광등보다 긴 수명을 가진다. 가시광 통신은 LED 가시광(RGB)을 이용한 무선 통신이다. 본 논문에서는 LED 조명을 이용하여 위치 기반의 실내 내비게이션을 구현하고 지하주차장에서 가시광 통신을 이용하여 주차 가능한 대수와 위치 등의 정보를 안내해 주는 주차안내 시스템을 설계하였다. 우리는 모의실험을 통하여 가시광 무선통신을 이용한 지하주차장에서 주차안내 시스템의 가능성을 알아보았다.

• 한국정밀공학회지
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• 제25권6호
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• pp.92-98
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• 2008

The target of this paper is to study on the usefulness of the SSHI technique as a wireless electrical power supply when it is driven by mechanical vibrations of low frequency. A THUNDER series a piezoelectric material (TH7-R), which has been developed by a NASA engineer is selected for this study. A mechanical motion vibrator supplies piezoelectric material with mechanical energy. An optical fiber sensor and a pulse generating circuit are used to accomplish the parallel-SSHI technique. As a result of this study, energy harvesting using SSHI technique results in a significant increase of the electrical power flow.