• Journal of Computing Science and Engineering
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• 제2권4호
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• pp.394-411
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• 2008

The data in automation and control systems can be achieved not only from different field devices but also from different OPC (OLE for Process Control) servers. However, current OPC clients can only read and decode the simple data from OPC servers. They will have some problems to acquire structured data and exchange the structured data. In addition to the large network control systems, the OPC clients can read, write, and subscribe to thousands of data points from/to OPC servers. Due to that, the most important factor for building a high performance and scalable industrial control system is the ability to transfer the process data between server and client in the most efficient and fastest way. In order to solve these problems, we propose a means to implement the OPC DA (Data Access) server supporting the OPC complex data, so that the OPC DA clients are able to read and decode any type of data from OPC servers. We also propose a method for caching the process data in large industrial control systems to overcome the limitation of performance of the pure OPC DA system. The performance analysis and discussion indicate that the proposed system has an acceptable performance and is feasible in order for applying to real-time industrial systems today.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 춘계종합학술대회
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• pp.133-138
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• 2001

가입자 Loop 대다수를 차지하는 동선케이블을 이용한 고속데이터서비스가 증가 발전하고 있는데 가입자선로에서 전송속도에 영향을 미치는 요소는 여러 종류가 있지만 전송로상에서 낙뢰, 전력유도 등 외부 전자기적 환경에 의해 통신회선에 잡음이 발생하고 이리한 잡음은 고속데이터서비스의 전송속도 및 전송품질에 영향을 미치게 된다. 된 연구에서는 가입자 통신회선에서 나타나는 잡음특성을 분석하고, 이를 기반으로 ADSL서비스의 전송품질에 가장 광범위하게 영향을 미치는 잡음을 가입자선로에 주입하여 케이블 거리별 전송속도를 측정하고 전송속도와의 관계를 분석하였다.

• 복식
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• 제57권6호
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• pp.145-159
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• 2007

Freed from its traditional confinement to the human body, postmodernism in fashion exposes the defectiveness of body and abstracts from the body under. As the 20th century art put premium on self-expression, the body itself became a powerful medium of expression in fashion. Using 'body' to analyze the clothing form, my study develops a framework by which to classify the fragmentation of the body in fashion. In order to inquire the formative style and aesthetic values expressed in fragmentation of the body in fashion, my study examines subjects from the discourse on the body to the fashion collections of the late 20th and 21st century, The results of the study are as follows. Fragmentation of the body in fashion means the break away from the idealized and standardized body for mass productions. It tends to experiment with extreme exaggeration in form, refusing to subscribe to the traditional values that build on the balance and symmetry of the body. The formative aspects of fragmentation are achieved through body casting, displacement, and deconstruction. The absence of physicality in fashion opposes the sartorial convention and symbolism that results in the discord between signifiant and $signifi{\tilde{e}}$ of clothing. Fashion continues to explore forms and images that transcend the traditional representations of the clothed body. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze fragmentation of the body in fashion, focusing on the relationship between the clothes and body.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(B)
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• pp.95-97
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• 2012

OMG(Object Management Group)의 데이터 분배 서비스(DDS: Data Distribution Service)는 발간(publish)/구독(subscribe) 모델에 기반하여 동일한 타입의 데이터를 실시간으로 주고 받는 데이터 중심의 분산 환경에서 많이 사용되는 통신 미들웨어 기술이다. 하지만 DDS는 실시간으로 발생하는 데이터에 대하여 일회성인 특징을 갖기 때문에 추후 데이터에 대한 분석, 검증 등을 위해 영속성을 제공할 필요성이 증대되고 있다. 이러한 추세를 반영하듯 RTI DDS, PrismTech Opensplice 등의 대표적인 DDS 시스템에서는 데이터베이스를 연동하기 위한 연구를 진행하고 있다. 실시간 통신 미들웨어인 DDS와 데이터베이스의 연동은 DBMS 애플리케이션이 일반적으로 데이터베이스를 사용하는 것뿐만 아니라 DDS의 시맨틱을 알지 못하더라도 데이터 중심의 발간/구독 모델을 유기적으로 활용할 수 있는 장점을 지닌다. 본 논문에서는 이를 위해 DDS 시스템인 DB-ReTiCom의 데이터베이스를 사용하기 위한 커넥티비티를 제안하고 사용자 친화적 인터페이스를 위한 변환 방법을 제시한다.

• 경영과학
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• 제32권2호
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• pp.37-50
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• 2015

The number of contracts for bundling services in a domestic telecommunication market records 1.3 miilion as of the first half year in 2007, and steadily increased to 8.97 million in 2010, to 12.76 million in 2013. In 2014, 70.4% of telecommunication service consumers are found to subscribe to bundling service. Bundling services provide consumers with benefits such as price discount, convenience, increase ARPU. However, a market dominant player in a specific market may transfer its market power to another market by selling bundling services. SSNIP has been adopted to provide a market definition. However, SSNIP is not suitable to measure the effect of market power transition through bundling services because SSNIP cannot measure the effect of changeover sales of bundling services. Thus, in this study, we have investigated the effect of market power transition through bundling services reflecting market power effect and quality upgrade using Gross Upward Market Power Pressure Index metho and reviewed UPP and derivative UPP models.

• 한국통신학회논문지
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• 제35권2A호
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• pp.134-141
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• 2010

본 논문에서는 지향성 안테나를 사용하는 IEEE 802.16 기반 무선 메쉬 네트워크(wireless mesh networks)의 성능 향상을 위한 스케줄링 알고리즘을 제안한다. 성능은 사용자 수에 따른 시스템의 수율과 각 노드 간의 지연으로 나타낸다. 분석 결과를 통해 제안된 알고리즘이 메쉬 네트워크 시스템의 지연을 줄여 시스템의 성능을 향상시킬 수 있음을 보인다. 본 논문의 결과는 향후 메쉬 네트워크, 멀티 홉 중계기 등의 다중 홉 시스템에서 각 SS(subscribe station)들의 공정성을 고려한 지향성 안테나 도입 시에 참고할 만한 가이드라인을 제시할 수 있을 것이다.

• 복식문화연구
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• 제19권5호
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• pp.970-980
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• 2011

As a type of intimate architecture, fashion has always mediated the dialogue between clothes and the body, or fashion and figure. This study seeks to inquire the current aesthetic consciousness of the body and dress in Japanese avant-garde fashion and intends to research the features and meanings in the pastiche of Western sartorial convention in Japanese avant-garde fashion in order to examine the changing aesthetic attitude in postmodern fashion. The study investigates subjects of the fashion collections of the turn of the twenty-first century, when pastiche strategies frequently appeared in Japanese avant-garde fashion, through the methodology of literature research and case analysis. The results of the study are as follows: by developing the strategy of pastiche, Japanese avant-garde fashion exposes the defectiveness of the Western idea of the idealized and standardized body for mass productions, thus freeing design from its traditional confinement to the human body. Drawing on the re-conceptualization of the sartorial convention of Western tradition, Japanese avant-garde fashion designers tend to experiment with extreme exaggeration in form, refusing to subscribe to the traditional Western values built on the balance and symmetry of the body. Through the combination of the past and the present as well as the inner-wear as outerwear strategy, the historical pastiche challenges convention and symbolism, which results in the discord between signifiant and signifi$\acute{e}$ of clothing.

• 대한임베디드공학회논문지
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• 제9권3호
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• pp.157-163
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• 2014

This paper demonstrates the benefit of using MOOS-IvP in the development of control system for Unmanned Underwater Vehicles(UUV). The demand for autonomy in UUVs has significantly increased due to the complexity in missions to be performed. Furthermore, the increased number of sensors and actuators that are interconnected through a network has introduced a need for a middleware platform for UUVs. In this context, MOOS-IvP, which is an open source software architecture, has been developed by several researchers from MIT, Oxford University, and NUWC. The MOOS software is a communication middleware based on the publish-subscribe architecture allowing each application to communicate through a MOOS database. The IvP Helm, which is one of the MOOS modules, publishes vehicle commands using multi-objective optimization in order to implement autonomous decision making. This paper explores the benefit of MOOS-IvP in the development of control software for UUVs by using a case study with an auto depth control system based on self-organizing fuzzy logic control. The simulation results show that the design and verification of UUV control software based on MOOS-IvP can be carried out quickly and efficiently thanks to the reuse of source codes, modular-based architecture, and the high level of scalability.

• 정보통신설비학회논문지
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• 제10권1호
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• pp.14-26
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• 2011

광 가입자용 송신 장치는 가입자 접속부의 ATM(Asynchronous Transfer Mode) 계층으로부터 ATM 셀을 비동기적인 방법으로 FIFO(First In, First Out)를 통해 수신하여 Idle/Unasigned 셀의 삽입, 셀에 대한 HEC(Header Error Correction) 계산, 그리고 셀 페이로드에 대한 스크램블링을 통해 VC4 신호 페이로드에 사상한다. 이때 VC4 POH(Path Over Head)상의 H4 바이트에 의해 셀의 시작점을 지시하고 동시에 POH 오버헤드에 대한 생성, 삽입을 통해 VC4 신호를 형성한다. 이 신호는 AU4 포인터 생성부에서 VC4의 시작점 J1을 생성하여 AUG버스를 통해 STM-1 신호 생성 부에서 프레임 형태로 출력된 후 155Mbps 속도로 광 신호로 변환되어 송신된다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.299-300
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• 2018

공공시설에서 청각장애인은 음성 알림을 제공받지 못하기 때문에 정보 획득의 수단으로 시설에 대한 전용 애플리케이션을 사용한다. 하지만, 각 시설마다 전용 애플리케이션을 사용해야하는 불편함이 있다. 본 논문에서는 청각장애인을 위한 알림 서비스 구독 방법을 제안한다. 제안하는 방법은 MQTT 프로토콜을 사용하여 알림 서비스를 설계하고, 애플리케이션을 통해 QR 코드를 스캔하면 알림 서비스를 구독한다. 알림 서비스를 구독한 청각장애인은 해당 알림 정보가 게시되는 경우 메시지를 전달받는다.