• Journal of information and communication convergence engineering
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• v.2 no.2
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• pp.76-79
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• 2004

The DS-SS (Direct Sequence Spread Spec1nun) transmitter is part of a low data rate (∼150 kbps - burst rate and 64 bps - average data rate) wireless communication system. It is traditionally implemented using Digital Signal processing chip (DSP). However, with rapid increase in variety of services through cell phones, such as, web access, video transfer, online games etc. demand for higher rate is increasing steadily. Since the chip rate and thereby the sampling rate requirements of the system are fairly high, the transmitter should implemented using Field programmable Gate Arrays FPGAs instead of a DSP. This paper shows the steps taken to get a working prototype of the transmitter unit on a FPGA based platform.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.351-358
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• 1998

This paper deals with the underwater image transmission system which includes in AUV(Autonomous Underwater Vehicle) Project(that is VORAM(Vehicle for Ocean Research And Monitoring)), developed by KIMM for survey and investigation of a sea-bed through transmitting the underwater image to the mother ship. The system presented in this paper consists of a transducer which has a 136KHz center frequency and it's 10KHz bandwidth, pre-amplifier, $\pi$/4 QPSK(Quadreature Phase Shift Keying) modulation/demodulation method, image compressing method using JPEG technique and modified Stop & protocol. The experimental results of the system is verified to a high performance with 9600 bps for transmitting the underwater image through the basin test. The results of test are also verified which allows to desirable transmission performance compared with the existing developed system and the possibility to put the practical use of survey and investigation. And, the viterbi coding and adaptive equalizer for cancelling the multipath effect are developing for more effective image transmission system. Also, these technique will very effectively adapt to realtime image transmission system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.356-357
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• 2007

In this paper, we developed an integrated miniaturized device which acquires and transmits the signal of ECG an interested heartbeat and body's temperature and humidity. Using an amplifier circuit on the electrodes and the radio frequency transmission, the developed system dispenses with the use of cables among the electrodes, amplifier, and the post processing system. The sensor signals are transmitted to the RF-wireless terminal that was developed using the micro controller Aduc812, LCD, RF-module (frequency 424MHz, 9600-bps). In results, the developed system improves not only the signal-to-noise ration in dynamic ECG & and body's temperature and humidity measurement, but also the user convenience.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.519-523
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• 2003

This paper describes the communication system of sequencing sorter. Generally sequencing sorter is a machine that sorts mails by delivery order. And designed sequencing sorter is composed of 5 physical modules. So, it is necessary to communicate with each module and to control this communication. A computer called Machine Management Computer, controls this. This paper is about the communication system with MMC and module controllers. This is PC-based, asynchronous full-duplex 4-wire serial systems. 3 protocol layers are presented and stop-and-wait flow control is adopted. Because designed sequencing sorter has to be operated high speed about 27,000 letters per hour, we analyzed the network traffic in the worst case. So, we could find that the communication system has to use above 115,200bps speed.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2006.06a
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• pp.629-655
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• 2006

A business process specification (BPS) plays the role of a contracted business scenario in the execution of the B2B business process instances. XML-based specification languages, such as BPSS, WS-BPEL, etc., are usually adopted for the specifications. However, composing complex XML-based specifications are not easy for humans. As an alternative, graphical modeling languages such as UML and BPMN can be employed. This paper presents an UML-based modeling method for graphically specifying ebXML BPSS instances (namely, business process specifications). UML diagrams, directly matching with ebXML BPSS, can be reused for understanding and generating ebXML BPSS instances. We discuss the value of tile method by developing a business reference library in the area of supply chain management.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.355-357
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• 2003

ebXML은 단일 세계 전자 시장의 형성을 목표로. UN/CEFACT와 OASIS의 주도로 만들어진 인터넷 상에서 기업간 전자 상거래를 위한 XML 기반의 표준 프레임워크이다. ebXML에서는 비즈니스 트랜잭션으로 구성되는 비즈니스 협업을 ebBPSS (ebXML Business Process Specification Schema) 스펙에 정의하는데, 기업의 비즈니스 시나리오를 기술하기 위해서 이 ebBPSS를 따르는 ebXML 비즈니스 프로세스 영세를 기술한다. 본 논문에서는 ebXML 비즈니스 프로세스 명세를 비즈니스 라이브러리에 저장하고, 서로 다른 시스템 사이에서 교환하기 위해 메타프레임워크인 XMI와 RDF 문서로 변환시키는 알고리즘을 제안한다. 이 알고리즘은 ebXML의 상호 운영성에 기여하여 ebXML 레지스터리에 저장된 비즈니스 프로세스 명세서의 유용성을 증대시킬 것이다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.121-130
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• 2012

In this paper, the structure of the Aladdin system was modeled by Petri nets for performance evaluation of 40G bps class Aladdin system which was developed in ETRI as the high-speed DDoS defensive tool. The efficiency analysis of the system architecture according to the input traffic of the Aladdin system was performed based on the modeling.

• Journal of Information Technology Services
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• v.18 no.1
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• pp.141-151
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• 2019

To protect workers from industrial accidents, IoT hazard detection system using LoRa network was designed and fabricated. LoRa networks can operate with low power consumption, wide coverage, and low usage fees. The hazard detection system consists of a sensor unit, a transceiver module, a LoRa base station, ThingPlug, and a monitoring device. We have designed an optimal risk-determining algorithm that can send information quickly in a working environment. As measured by TTA, the implemented system has been found to be able to deliver the worker's location, ambient temperature, and carbon monoxide density to the administrator through the user interface. The implemented system showed a bit rate of 290bps and a maximum application range of 6 km.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.637-638
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• 2011

최근 수중 통신에 대한 관심이 급증함과 동시에 수중에서 음성, 영상과 같은 멀티미디어 데이터 전송에 대한 요구가 증가하고 있다. 이러한 추세에 발맞춰 수중 통신에 대한 연구가 활발히 진행되고 있으며 본 논문에서도 수중 통신 모뎀에 대한 연구를 수행하였다. 본 논문에서는 70 kHz의 초음파를 이용하는 진폭 편이 변조 방식의 수중 음향 통신 모뎀을 구현하고 구현한 모뎀의 성능을 평가하였다. 실험은 경기도 양평 양수리에 위치한 북한강에서 이루어졌으며, 실험을 통해 전송 거리 50 m, 전송 속도 200 bps, BER 성능 $1{\times}10^{-3}$ 의 결과를 얻었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.639-641
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• 2011

최근 수중 통신에 대한 관심이 높아짐에 따라 수중 통신 기술 개발을 위한 연구가 활발히 이루어지고 있다. 본 논문에서는 수중 음향 통신 모뎀을 위한 연구를 수행하였고, 모뎀의 성능을 한강에서 실험을 통해 검증하였다. 모뎀에 사용된 MCU는 ARM Cortex-M3이며, 모뎀의 최대 데이터 전송 속도 및 최대 전송 거리는 각각 200 bps, 150m 이다.