• 한국자동차공학회논문집
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• 제14권5호
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• pp.17-24
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• 2006

Anti-lock brake system(ABS) are designed to prevent wheel lock on all wheels of the vehicle by sensing wheel angular speed, processing the speed sensor signals in suitable digital electronic control circuits and comanding electrohydraulic actuators to control brake pressure. This study considers a control of ABS using wheel circumferential acceleration thresholds which avoids dangerous wheel locking due to excessive brake pressure during the vehicle braking and discusses the 3-channels, 3-sensors ABS system that employs "independent control" technique for the front wheels and "select low" technique for the rear wheels. The validities of the ABS such as vehicle stability, steerability and stopping distance during braking are assured through the vehicle tests on uniform asphalt straight roads.

• 한국정밀공학회지
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• 제13권8호
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• pp.120-127
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• 1996

Anti-lock Brake System has been developed to reduce tendency for wheel lock and improve vehicle control during sudden braking on slippery road surfaces. This is achieved by controlling the braking pressure, avoiding wheel lock, while retaining handling and brake performance. This paper is concerned about pressurecharacteristics of hydraulic modulator. Experimental sets which is consists of hydraulic modulator, duty controller, pressure regulator, pressure senset is consuructed. System modelling and computer simulation are performed for comparison with experimental results. Brake wheel pressure are measured under various driving pulse. The result of experiment show fairly agreement with the simulation. As a result, it is known that wheel pressure is affected by duty ratio, orifice diameter through computer simulation.

• 한국비블리아학회지
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• 제6권1호
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• pp.47-80
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• 1984

The aim of this paper is to study the classification and arrangement system, the original texts, and the bibliographic deseription of Dae-Jang-Mock-Lock. The results of this study can be summarized as followings; 1. The first carving of Dae-Jang-Mock-Lock was assumed to be completed at latest by 1087 (King Sun-Jong 4, Koryo) when the first carving of Dae-Jang-Kyong, the complete collection of Buddhist Sutra, mas finished. Henee, Dae-Jang-Mock-Lack is safely said to be the oldest catalog in Korea. 2. The major function of Dae-Jang-Mock-Lock mas to facilitate the job of printing, managing, or arranging the Sutra tablets, rather than to serve as its references. 3. Dae-Jang-Mock-Lock mas classified in accordance with the classification sys tern of Gae-Woon-Suck-Kyo-Lock, a chinese Buddhist catalog. This system classified the complete collection of Buddhist Sutra into the three categories of "Mah$\={a}$y$\={a}$na Tripitaka", "Hinayan$\={a}$ Tripitaha", and "collected Biographies of Samgha", at the first gradation. And then the Mah$\={a}$yan$\={a}$ Tripitaka mas divided into the three categories of "Mah$\={a}$y$\={a}$na Sutra", "Mah$\={a}$y$\={a}$na Uparaksa", and "Mah$\={a}$y$\={a}$na Upadesa", at the second gradation. In the same manner the "Hinayan$\={a}$ Tripitaka was divided into "Hinayan$\={a}$ Sutra", "Hinayan$\={a}$ Uparaksa", and "Hinayan$\={a}$ Upadesa". The "Collected Biographies of Samgha" was divided into Brahman Samgha and Chinese Samgha. For this reason we Can name this main classification system as a Tripitaka Classification. 4. The first carving tablets of the Buddhist Sutra from Choen Shelf (天函) to Young Shelf (英函) were the same Sutra that were included in Gae-Woen-Suck-Kyo-Lock (開元釋敎錄), except those 4 omitted sutras of 22 volumes. But the other 7 sutras of 24 volumes were included as an extra addition in "Dae-Jang-Mock-Lock." 5. The 40 shelves and 376 volumes of Buddhist Sutra from the Doo Shelf (杜函) to the Kyong Shelf (輕函) in Dae-Jang-Mock-Lock were copied from the texts of Guran Edition (契丹本) 6. The 36 shelves of Buddhist Sutras from the Bun shelf (磻函) to the Mil shelf (密函) in Dae-Jang-Mock-Lock were the same as those included in Sock-Jung-Woen-Suck-Kyo-Lock (續貞元釋敎錄), except the 3 omitted sutras.

• 한국컴퓨터정보학회논문지
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• 제4권2호
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• pp.105-112
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• 1999

확산대역통신은 CDMA 시스템에서의 핵심기술이지만 SS통신에서의 문제점은 동기 방법이다. 동기방법에는 DLL(Delay Lock Loop), Tau-dither Loop, SO(Synchronous Osillator) 등이 있다. 그러나 아날로그 동작시에는 회로의 크기가 커지고 조정이 어려운 문제가 있어 본논문에서는 Digital Delay Lock Loop (DDLL)을 제안하고 실험을 통해 그 성능을 평가하였다.

• 산업기술연구
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• 제18권
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• pp.355-362
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• 1998

The deadlock detector is a DBMS sub-component that examines periodically whether system is in a deadlock state based on lock waiting information of transactions. The deadlock detector and transactions execute concurrently in a DBMS and read and/or write the lock waiting information simultaneously. Since the lock waiting information is a shared one, we need an efficient method guaranteeing its physical consistency by using mutual exclusion. In this paper, we propose a new method that effectively guarantees physical consistency of lock waiting information. Two primary goals of our method is to minimize the processing overhead and to maximize system concurrency.

• 한국광학회지
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• 제30권1호
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• pp.1-7
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• 2019

휴대용 대공유도 미사일(Man-Portable Air Defense System)은 플룸의 중적외선 신호를 추적하는 적 항공기의 대응무기체계이다. 안개 조건에서 입자들에 의한 다중 산란현상은 중적외선 파장에서의 투과율과 휴대용 대공유도 미사일 탐지성능에 영향을 준다. 그러므로 본 연구에서 다양한 안개조건과 플룸의 특성에 따른 휴대용 대공유도 미사일의 lock-on range를 분석한다. 안개 조건에서의 광학적 소멸특성과 투과율을 분석하기 위해 미산란(Mie scattering) 이론과 복사전달방정식의 분석적 해를 활용하였다. 뿐만 아니라 중적외선 대체광원으로서 섬광탄 화염 신호를 운용했다. 다양한 시정 및 화염 온도조건에서 분석된 lock-on range는 mist 조건에서 크게 감소하며, 화염 온도가 높아질수록 증가하는 것으로 확인하였다.

• 오토저널
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• 제24권2호
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• pp.108-113
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• 2002

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.560-563
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• 2015

기존에 사용되어지는 도어락 시스템은 키 또는 카드, 패드를 이용하는 방식으로 복제, 분실, 훼손 등의 위험과, 타인에게 노출되는 문제점을 가지고 있다. 본 논문에서는 기존의 도어락 시스템 문제점을 보완하고자 스마트폰에 내장된 Bluetooth통신과 OTP(One-Time-Password), Hide-Key 인증방식 및 Arduino를 활용한 스마트폰 기반의 무선 OTP 도어락 시스템 설계 및 구현함으로써 사용자들은 보안 및 노출의 위험성에서 벗어나 보다 편리하고 안전한 생활을 가능하게 한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1836-1840
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• 2003

This paper, we propose a new phase-locked loop (PLL) system with the controllable output phase, independent from the output frequency, and lock-up time. This PLL system has a dual control loop is described, the inner loop greatly improved VCO characteristic such as faster speed response as well as higher operation bandwidth, to minimize the effect of the VCO noise and the power supply variation and also get better linearity of VCO output. The main loop is the heart of this PLL which greatly improved the output frequency instability due to the external high frequency noise coupling to the input reference frequency also the main loop can control the output phase, independent from the output frequency, and reduce the lock-up time of the step frequency response. The experimental results confirm the validity of the proposed strategy.

• 융합신호처리학회논문지
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• 제15권3호
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• pp.97-103
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• 2014

근래에 와서 출입문의 물리적 보안장치로써 디지털 도어록의 사용이 보편화되었다. 기존의 자물쇠 방식 보다는 훨씬 편리한 기능이지만 도어록에 전기 충격을 가할 경우 열리는 문제점이 노출되었다. 본 연구에서는 도어록 기기를 안으로 숨기고 증강현실을 이용해 도어록을 사용자의 스마트폰 화면에 띄우게 하여 보안성을 높이는 방법을 제안한다. 아울러 메모노트를 띄우는 기능을 추가하여 가족 간의 의사소통을 원활하게 해주는 기능을 부가하였다. 본 연구 결과는 가상으로 만든 출입문과 아두이노와 와이파이 쉴드 그리고 자물쇠를 제어하기 위한 모터를 사용하여 구현하였으며, 만족할 만한 실험결과를 보였다.