• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.547-552
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• 2003

In this thesis, interference phenomena of bluetooth networks requiring Security were minimized; strengthened security of piconet by assigning an identical PIN code to bluetooth devices, which was establishing a specific piconet during authentication stage. To establish a bluetooth piconet system. an unique ID was assigned to each bluetooth device, communication algorithms having different data formats between devices was designed, and an embedded hardware module using ARM processor and uCOS-II RTOS was implemented. About 30% of CPU efficiency in the module was increased by modifying functions including block parameters to work as nonblocking; by the increased efficiency of total piconet, the module could be used as an access point. The module could transmit maximum 10 frames of image and also audio signal by switching the packet effectively according to channel condition. By above-mentioned process, video, audio, and data could be well transmitted by the bluetooth managing program and the possibility of a commercial remote control system using bluetooth technology was suggested.

• The Journal of Information Technology
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• v.5 no.1
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• pp.69-77
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• 2002

The Bluetooth is expected to be one of the most popular wireless telecommunication technology in the near future, and the protocol stack is essential to providing the various services with the Bluetooth-embedding systems or devices. The Bluetooth specification is an open, global specification defining the complete system, however, the protocol stack is usually implemented partly in hardware and partly as software running on its system, with different implementations partitioning the functionality between hardware and software in different ways. I investigate how to design and implement the Bluetooth protocol stack according to its specification. I focus on the HCI and the lower layer of the software protocol stack as a basic step for the development of our own protocol stack. As a result, paper provides how to partitioning the role of HCI layer, and how to implement the relationship between HCI packets, it's functionality and the flow control. Experiments show the discovering other Bluetooth devices and their connection. Furthermore experiments demonstrate the proper operation of data communication between the Bluetooth modules.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.7
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• pp.923-928
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• 2014

Communication underwater is severely limited when compared to communications in air because water is essentially opaque to electromagnetic radiation except in visible range. Acoustic systems are capable of long range communication, but offer limited data rates and significant latency due to the speed of sound in water. On the other hand, optical wireless communication has been proposed as one of the best alternatives to meet the requirements of the underwater observation and subsea monitoring systems. It will help In this study, we are developing an underwater optical communication system that integrates with a depot ship floating on the water. An interface between LED lighting communication system and Bluetooth module is presented to support the underwater-to-air communications. Error free image and text transmission at 3 m of water were achieved at bit rates of 230.4 kbps. This development effort will enhance infrastructure to efficiently interconnect between underwater wireless systems and command ship networks for underwater monitoring.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.103-111
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• 2023

Recently, many universities have used various electronic attendance systems such as NFC, QR code, Sound-QR, Bluetooth BLE authentication, and face recognition to process attendance. However, existing methods have various problems such as attendance errors due to deformation of authentication signals, mis-recognition attendance from outside the classroom, and difficulty to process seat absence during class. Therefore, this study proposes a high-frequency signal-based electronic attendance system to solve these problems and manage more accurate electronic attendance. As the high-frequency signal replaces the BLE signal, and the transmission range of the signal is limited to the classroom, and the signal value can be immediately changed if a change of the signal is needed. To verify the performance of the proposed system, we conducted a comparative experiment with the Bluetooth based electronic attendance system, and as a result, the proposed method showed high accuracy. Thus, the proposed method will be a useful service that can be immediately used in smart device-based electronic attendance system.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.2
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• pp.33-42
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• 2004

Controlling household devices using an infra-ray (IR) has a limitation since the IR signal cannot only be extended, but also cannot be transmitted over the physical barrier. Using a radio frequency (RF) may overcome these shortcomings. Bluetooth is one of the emerging RF_based standard protocols for short-range wireless communications among various control devices. In this paper, we describe a control system for household appliances using Bluetooth under embedded Linux environment. The control system consists of a centralized main controller and geographically scattered wallplates. Some of the challenges and lessons learned will be outlined in the presentation. As a result of this research, we found that the Bluetooth is a promising technology for realizing wireless control systems for household appliances.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.11a
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• pp.30-34
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• 2001

본 논문에서는 근거리에 놓여있는 노트북, 휴대폰, PDA, 혜드셋 등 각종 이동 가능한 장치들을 하나의 무선네트워크로 연결할 수 있는 블루투스의 베이스밴드 시스템 프로토콜 기능을 분석하고 설계하였다. 즉, 전체적인 논리 기능구조를 설계한 후 하드웨어로 구현될 패킷생성 블록, HEC와 CRC 기능블륵, Whitening/Dewhitening 기능블록, FEC 기능블록, 입출력 블록(TX, RX 루틴), 클럭 생성 기능블록, 주파수 선별 기능블록, 오디오 기능블록 그리고, 패킷 제어 블록들의 처리절차를 Verilog HDL 코드로 설계 및 검증하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.467-468
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• 2015

본 논문에서는 주차장의 주차 공간 정보와 블루투스 비콘 정보를 활용하여 IoT 기반 스마트 주차정보 시스템을 구현하였다. 주차장의 주차 센서는 주차 정보를 실시간으로 서버에게 전달하며 차량 운전자는 스마트폰 앱을 실행하고 주차장에 진입한다. 스마트폰은 그 주차장의 블루투스 비콘 신호를 이용하여 주차 위치를 자동으로 인식하며 주차하려는 층의 주차 정보를 한눈에 확인할 수 있다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.752-755
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• 2004

선박용 엔진의 제작에 있어 크랭크 샤프트 조립 시 1 회전의 상태에서 크랭크 스루 간의 디플렉션의 상대값이 정상오차 범위를 넘어서는지 확인한 후 조립상태를 보정하게 된다. 기존의 방법은 다이얼 게이지를 사용하여 측정 담당자가 베드 플레이트 내에 들어가 크랭크 샤프트 회전 시 따라 돌면서 직접 육안 확인을 통해 측정이 이루어졌다. 이 때, 측정의 불편함과 열악한 작업환경 하의 안전 문제가 야기된다. 이러한 문제점을 해결하기 위해 본 연구에서는 블루투스 통신을 이용하여 디지털 게이지를 사용한 측정장치 기구부의 신호를 무선으로 받아서 작업자는 베드 플레이트 외부에서 측정이 가능하도록 하는 시스템의 개발하였다. 이를 통해 작업의 편리성 및 안정성을 확보했으며, 디지털 측정을 통한 측정의 정확도를 향상시켰다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.651-652
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• 2012

Wireless monitoring and hybrid mobile web have become an emerging area of research in recent year. This paper deals with the design and implementation of mobile web page for sensing data monitoring. The mobile web monitoring system for sensing data transmission is implemented by 8-bit AVR microcontroller and bluetooth communication module.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.653-654
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• 2012

Wireless sensor monitoring network has become an emerging area of research in recent year. This paper deals with the design and development of remote monitoring system using Android bluetooth protocol. The remote monitoring and measurement H/W system are implemented by ATmega128 MCU and bluetooth communication module.