• 한국통신학회논문지
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• 제36권11B호
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• pp.1329-1338
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• 2011

본 논문에서는 분산 메모리 아키텍처를 사용하는 멀티프로세서에서 가장 병목 현상이 심한 집합통신 중 브로드캐스트를 위한 알고리즘 및 하드웨어 구조를 제안한다. 기존 시스템에서 집합통신은 프로세싱 노드의 통신포트 상태가 busy 혹은 free 인지를 고려하지 않고 MPI libray cell 에 의해서 점대점 통신으로 변환되어 진다. 만약 브로드캐스트 통신을 하는 동안에 간섭하는 점대점 통신이 있다면, 브로드캐스트 통신의 전송 속도는 저하된다. 따라서 본 논문에서는 각각의 프로세싱 노드의 상태를 고려하여 통신 순서를 결정하는 브로드캐스트 통신 알고리즘을 제안하였다. 제안하는 구조의 알고리즘은 각 프로세싱 노드의 상태에 따라, free 상태의 통신 포트를 가진 프로세싱 노드의 통신 포트에게 우선적으로 메시지를 송신하여 전체적인 집합통신 시간을 단축하였다. 본 연구에서 제안하는 브로드캐스트 통신을 위한 MPI 유닛은 SystemC로 모델링하여 평가하였다. 또한 본 구조는 16노드에서 브로드캐스트 통신의 성능을 최대 78% 향상시켰고, 이는 MPSoC(Multi-Processor System-on-Chip)의 전체적인 성능을 높이는데 유용하다.

• Journal of Contemporary Eastern Asia
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• 제12권2호
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• pp.35-47
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• 2013

This study aims to understand haiku phenomena from the viewpoint of communication, which emerges from reciprocal relationships among haiku poets, haiku societies, media on haiku, and other establishments relating to haiku. Such an analytic point of view, which tries to consider both the operation of each autonomous agent and that of the whole system consisted by the agents, is included in the realm of second-order cybernetics. The operation of a system cannot be reduced completely to a system's individual components, which is why such a viewpoint is required. Fundamental informatics, which is employed as a theoretical framework, and two haiku movements, which include shin keiko haiku ("new-trend" haiku) and dento ha haiku (Hototogisu-school haiku), forming an important part of modern haiku history, are the focus of this study. As a result, modern haiku history is considered to be an evolution of a haiku system, whose main incentive is an awareness of the production mechanism of haiku communication occurring through second-order observations in the system. This study also illuminates how haiku poets, haiku societies, and media covereage of haiku play roles in the evolution of the haiku system.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.339-342
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• 2005

In order to support ultrawide-band signal generation for low rate WPAN, several types of signal generation mechanisms are suggested such as Chaos, Impluse, and Chirp signals by the activity of IEEE 802.15.4a. The communication system applied chaos theory may have ultrawide-band characteristics with spread spectrum and immunity from multipath effect. In order to use the advantage of chaotic signal generation, we introduce the system implementation of communication and networking systems with the chaos UWB signal. This system may be composed of mainly three parts in hardware architecture : RF transmission with chaotic signal generation, signal receiver using amplifiers and filters, and 8051 & FPGA unit. The most difficult part is to implement the chaotic signal generator and build transceiver with it. The implementation of the system is devidced into two parts i.e. RF blocks and digital blocks with amplifiers, filters, ADC, 8051 processor, and FPGA. In this paper, we introduce the system block diagram for chaotic communications. Mainly the RF block is important for the system to have good performance based on the chaotic signal generator. And the main control board functions for controlling RF blocks, processing Tx and Rx data, and networking in MAC layer.

• 한국정밀공학회지
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• 제22권6호
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• pp.135-143
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• 2005

The shoes process management monitoring system for supporting SCM is developed in this study. This system consists of a monitoring program, a conveyer system, a pneumatic unit, a controller, an USB camera, and a server and a client computer. To operate the developed system easily, the monitoring program using LabVIEW in the Windows environment is developed. This program consists of 5 modules: production management, inventory control, media management, defective management, and communication management. The developed system has several advantages: reduced time for managing process work, decreased labor costs, effective operation, and continuous work without an operator. Nowadays advanced manufacturing companies are trying to find a way to check the performance of their production equipments and plants from remote sites. Thus, to manage the developed system from remote sites, communication network is constructed. In order to evaluate the performance of the monitoring system, experiments were performed. The experimental results showed that the developed system provided a reliable performance and a stable communication.

• 자동차안전학회지
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• 제15권4호
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• pp.65-70
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• 2023

In the paper, we propose a design method and process of a hybrid V2X communication module that combines WAVE communication, LTE-V2X communication, and legacy LTE communication in evaluating vehicle V2X electromagnetic compatibility. C-ITS is suitable for safety service applications due to its low latency, and legacy LTE is suitable for applications such as traffic information and infotainment due to its high latency and high capacity. In order to evaluate the V2X communication system, the evaluation equipment must have communication performance of the same level or higher. The main design contents presented in this paper will be applied to the implementation of a hybrid V2X communication module for electromagnetic compatibility evaluation.

• 한국전자통신학회논문지
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• 제10권3호
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• pp.341-347
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• 2015

본 논문에서는 중소형 선박에 적합한 저가의 VDR(Voyage Data Recorder)시스템을 설계하고, 해양 항법시스템의 효율성 향상을 위해 해양 항법시스템과 VDR이 시리얼 통신 혹은 이더넷 기반으로 데이터 통신을 하여 VDR에 연계된 항해통신 장비 및 센서 등의 데이터들을 항법시스템에 저장 및 출력할 수 있도록 구현하고자 한다. 또한, 육상에서 VDR의 기능과 동일한 역할을 수행하는 "차량용 블랙박스"(차량 위치, 영상, 음성저장)와 같이 VDR 고유 기능을 통한 정확한 해난 사고 원인 분석이 가능하게 중소형선박에도 확대 적용하고자 소형 경량화로 설계하고자 한다.

• 전기학회논문지
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• 제64권9호
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• pp.1398-1405
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• 2015

Domestic railway communication in Korea has been introduced for mutual communications among control center, operation staffs, and maintenance staffs. It has been mainly used as railway disaster and safety functions from VHF and UHF from 1980’s and TRS-Astro and TRS-Tetra from the 2000’s. Recently for urban railways communications, 18GHz and 2.4GHz ranges have been utilized for image transmissions and control command communications, respectively. This paper analyzes technical development of LTE-R, LTE communication for Railways, that has been designed as a single integrated railway wireless network in order to merge the current various communication systems. In this paper, we present the details of the examination of the LTE-R test-bed using 2.6GHz test frequency in Daebul test line through CW test and optimization test.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.109-110
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• 2006

The performance of a digital baseband signal processing and data transmission rate depends on the modulation technique. In this paper, We implemented DSP communication system for Underwater acoustic communication using by adaptive BPSK modem technique. In order to implement adaptive modem, we suggested SNR detection block. SNR detection block has the reference SNR value that selects between window filter path and matched filter path. In this paper, suggested system is based on software interface and all Hardware(PLL, modem filter, equalizer etc) is implemented by software, exclusive of DSP, A/D, D/A converter, SDRAM and Flash memory.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권12호
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• pp.3003-3017
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• 2013

In this paper, we investigate the outage performance of a cognitive relay network. We consider mutual interference in an independent, non-identically distributed Nakagmai-m fading environment. We first derive the close-form outage probability expression, which provides an efficient means to evaluate the effects of several parameters. This allows us to study the impact of several parameters on the network's performance. We then derive the asymptotic expression and reveal that the diversity order is strictly determined by the fading severity of the cognitive system. It is not affected by the primary network. Moreover, the primary network only affects the coding gain of the cognitive system. Finally, Monte Carlo simulations are provided, which corroborate the analytical results.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권4호
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• pp.117-122
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• 2003

The AC power lines and signal lines of info-communication networks are routed on overhead poles and are highly exposed to lightning strikes. Due to the potential difference between grounding points of AC power lines and signal lines, the electronic equipments connected to the signal lines can easily be damaged by lightning surges. In this work, in order to develop reliable methods of protecting information and communication facilities from lightning surges, the reliability and performance of SPDs (surge protective devices) were experimentally investigated in an actual-sized test circuit. The behaviors of SPDs against lightning surges from AC power lines and signal lines and the coordinated effects of SPD installation methods were evaluated. As a consequence, it was confirmed that the bypass arrester methods and common grounding system are both highly effective.