• 디지털산업정보학회논문지
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• 제5권4호
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• pp.151-160
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• 2009

While portable and wireless devices are pouring, a new network technology is needed as a breakthrough. The new network technology features large delays, intermittent connectivity, and absence of an end-to-end path from sources to destinations. A network which has one of those characteristics is called DTNs(Delay Tolerant Networks). The main 4 routing methods have been researched so far in extream environment. In this paper, we look into the reliability of DTMNs(Delay Tolerant Mobile Networks) in several different situations, and propose an algorithm that selects a positive routine by sending the only information of its position when making a connection to a detected node. We simulate the proposed algorithm here in DTN using ONE simulator. As a result, it shows that the algorithm reduces the number of message transmission each node.

• 한국경영과학회지
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• 제16권1호
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• pp.135-146
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• 1991

This paper shows the infinite horizon model of Partially Observable Markov Decision Process with lagged information. The lagged information is uncertain delayed observation of the process under control. Even though the optimal policy of the model exists, finding the optimal policy is very time consuming. Thus, the aim of this study is to find an .eplison.-optimal stationary policy minimizing the expected discounted total cost of the model. .EPSILON.- optimal policy is found by using a modified version of the well known policy iteration algorithm. The modification focuses to the value determination routine of the algorithm. Some properties of the approximation functions for the expected discounted cost of a stationary policy are presented. The expected discounted cost of a stationary policy is approximated based on these properties. A numerical example is also shown.

• 한국CDE학회논문집
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• 제4권4호
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• pp.371-380
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• 1999

This study proposes a process information model which can integrate various activities during the product development process, the system which can manage the process. Development process information will allow designers and managers to access previous tasks readily and utilize the information in making decisions at hand. While developing products in heterogeneous and distributed environments, concurrent and collaborative designs can be achieved by STEP. The process model in this study divides the task of product development into two fundamental parts, Specific Process(SP) and Normal Process(NP). SP includes the specific information and refer to those defined by prior STEP. NP is routine process excluded from being defined as SP. Due data information can be added to manage development pace and to show delayed tasks. As two or more different processes can be linked to show the entire development flow, Static STEP information can be dynamically interlaced. Remote location operations can be incorporated on the Internet using STEP, and information can be shared. The system has been built upon a process model schema so that task stage, design history, and different development style can be managed and accessed for each component. The system has been proven efficient in information management and exchange by several scenario testings.

• 한국통신학회논문지
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• 제18권12호
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• pp.1841-1854
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• 1993

Ethernet에 음성신호의 전송을 위한 패킷음성 프로토콜을 PC 구현하였다. 구현한 패킷음성 프로토콜은 CCITT의 G.764 패킷음성 프로토콜을 수정하여 사용하였다. 이를 위하여 ethernet을 통한 음성통신을 하기 위한 하드웨어 시스템을 설계하였는데, 전화기 인터페이스부분, 음성처리부분, PC인터페이스부분 및 제어부분으로 나누어진다. 소프트웨어는 OSI 7 계층에 맞추어 설계하였으며 ethernet device driver, 전화기 인터페이스 하드웨어 driver 그리고 패킷음성 프로토콜 처리부분으로 구성되어 있다. 실제 실험결과 ethernet을 통하여 전화를 연결하고 만족한 음성통화를 할 수 있었다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 추계학술발표회 논문집
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• pp.157-162
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• 2003

The 3D Image which embodies real object to 3D space of computer enables various geometrical analysis as well as visualization of complex 3D shape by giving sense for the real and cubic effect that can not be offered in 2D image. Human gives real object to same physical properties in 3D space imagination world of computer, and it is expected that this enables offering of various information by user strengthening interface between human-computer to observe object in real condition. In this study, formal style routine of 3D image creation applying digital photogrammetry was designed for more practical, highly trusty 3D image creation, and the system was emboded using object-oriented technique which strengthen user interface. Also, the discontinuity information about rock slope using 3D image is acquired that is orientation, persistence, spacing and aperture etc.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(A)
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• pp.279-281
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• 2012

고도화된 네트워크에서 성능 문제는 라우터 설계에 있어서 등가교환 하기 쉽지 않다. 그러나 IPv4 프로토콜의 한계점과 새로운 네트워크 계층의 프로토콜의 필요성이 대두되면서 소프트웨어 라우터가 각광을 받기 시작하였고 이들 성능 향상을 위한 연구가 활발히 진행 중이다. 본 논문에서는 이러한 소프트웨어 라우터 성능 향상 연구의 일환으로 리눅스를 이용한 라우터의 성능 병목 지점 중의 하나가 소프트웨어 인터럽트 처리 루틴임을 제시한다. 그리고 이를 해결하기 위해 소프트웨어 인터럽트 서비스 루틴을 단축시켜 인터럽트 처리 속도를 향상시키는 방법을 제시한다. 또한 실험을 통해 이와 같은 방법이 전통적인 리눅스 라우팅에 비해 2배 가량의 성능 향상이 있었음을 보인다.

• Asia pacific journal of information systems
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• 제11권1호
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• pp.25-43
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• 2001

The evolution of EDI has opened the flexible and efficient way for business to conduct a greater portion of the routine buyer-seller business activities online. This study focuses on the role of factors that change the innovation characteristics for implementation success of EDI. Three factors promotional efforts, proactive implementation strategy, and provision of technical expertise are proposed to affect EDI implementation success, as these factors directly influence three general and most important attributes of innovation relative advantage, compatibility, and complexity respectively. Hypotheses indicate that promotional efforts, proactive implementation strategy, and provision of technical expertise directly affect EDI implementation success that is represented by three variables volume, depth, and diversity. A structural equation modeling approach(LISREL) is used to analyze data from EDI adopters. The results show that proactive implementation strategy and provision of technical expertise positively affect implementation success of EDI. Given the significant impact of the wide spread use of the EDI system, this study offers quite useful insights on the factors facilitating innovation characteristics under which EDI can be successfully diffused in organizations.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.792-797
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• 2002

In the following paper two algorithms, suitable for the analysis of panchromatic data as provided by KOMPSAT-1 will be presented. One is a texture analysis which will be used to create a settlement mask based on the variations of gray values. The other is a fusion algorithm which allows the combination of high resolution panchromatic data with medium resolution multispectral data. The procedure developed for this purpose uses the spatial information present in the high resolution image to spatially enhance the low resolution image, while keeping the distortion of the multispectral information to a minimum. This makes it possible to use the fusion results for standard multispecatral classification routines. The procedures presented here can be automated to large extent, making them suitable for a standard processing routine of satellite data.

• 한국정보전자통신기술학회논문지
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• 제3권2호
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• pp.58-63
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• 2010

암호화 작업은 많은 연산시간을 요한다. 본 논문에서는 암호화에 수반되는 연산시간을 분석하기 위해 평문의 압축과 가변의 블록 크기, 라운드 횟수의 사용자 설정 및 단계별 작업과정의 선택적 적용 등의 네 가지 원리에 기초해서 AES 구조를 확장하였다. 실험은 C++로 수행하였으며 실험을 통해 최적의 입력 블록 크기를 도출하였다.

• 한국정보통신학회논문지
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• 제5권3호
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• pp.483-491
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• 2001

Java RMI는 네트워크를 통해 연결된 분산 환경 시스템에서 원격 컴퓨터에 존재하는 메소드간에 정보를 주고받을 수 있는 어플리케이션을 개발할 수 있도록 개발된 모델이다. 본 논문에서는 Java RMI를 이용하여 원격 컴퓨터에 존재하는 객체의 메소드를 연결하는 시스템을 설계하고 구현하였다. 이를 위해, 클라이언트가 이용할 수 있는 동적 메소드 연결 인터페이스 및 구현 부분을 API 형식으로 완성하였다. 또한 동적 메소드 연결시에 서버에서 사용하는 동적 메모리 할당, 소멸 등을 위한 관리 루틴을 완성하였다.