• Informatization Policy
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• v.26 no.2
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• pp.24-45
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• 2019

This paper analyzes the size of direct and indirect impact of the information and communication technology(ICT) producing sector to the Korean economic growth We first divide the entire economy into the ICT producing sector and the ICT using sector, and estimate the contributions to the economic growth by each sector. We also try to answer the question on what the possible causes of the ICT producing sector's contribution are to growth. In oder to find the answer, we focus on the change in the relative prices of ICT products produced in the ICT producing sector and examine the long-term relations among the relative prices of ICT products, the ratio of ICT products used in the ICT using sector as an intermediate input, and the output of the entire economy. We find that the overall economic growth has been weakened but the ICT sector's contribution to the growth has increased. Specifically, the indirect contribution of the ICT producing sector, through the ICT using sector, to economic growth was greater than the direct contribution of the ICT producing sector itself. We also find a stable, long-term negative relation between the relative prices of ICT products produced in the ICT producing sector and the ratio of ICT products as an intermediate input in the ICT using sector. In addition, the decrease in the relative prices of ICT products produced in the ICT producing sector increases the use of ICT products in the ICT using sector and the output of the entire economy. These findings can be interpreted that the price decrease in the ICT products improves the production efficiency in other sectors and helps directly and indirectly, accelerating growth of the entire economy.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.8
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• pp.4-11
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• 2002

유동장을 해석하는 궁극적인 목적 중 하나는 해석 결과를 바탕으로 더 나은 성능을 가지는 형상을 설계하는 것이라 할 수 있다. 해석된 정보들은 대상인 제품의 전체 형상 및 각 부분 부품을 설계하는데 사용되고 설계의 문제점과 개선점 및 성능을 예측하는데 사용된다.

• Journal of the KSME
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• v.28 no.2
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• pp.107-112
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• 1988

1970년대 초부터 기계시스템의 해석을 위한 컴퓨터 프로그램들이 소개되기 시작한 기계시스템의 동력학적 해석은, 해석 자체의 중요성 못지 않게 보다 나은 설계를 위해서도 필요하다고 사료 된다. 각 부품의 설계도 중요하지만, 시스템 전체를 다루는 해석도 중요한바, 앞으로 국내에서도 이 분야의 연구가 활발하여 자동차 산업에 많은 도움을 줄 수 있기를 바란다.

• Journal of Ocean Engineering and Technology
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• v.13 no.4 s.35
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• pp.10-18
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• 1999

본 논문에서는 대형구조물의 해석에 있어서 부분구조합성법과 섭동법을 이용하여 복잡한 비선형시스템의 해석방법을 제안하였다. 해석방법은 전체시스템을 먼저 몇 개의 분계로 분할한다. 각 분계의 운동방정식에 비선형항이 존재하여도 전체시스템의 지배적 진동모드는 선형모드라는 가정하에 이 시스템의 각 분계를 모드좌표로 변환한다. 이때, 비선형항은 근사적으로 변환한다. 그리고 섭동법을 이용하여 각 분계의 모드좌표방정식은 섭동좌수별로 정식화되어 순차적으로 구해진다. 비선형의 감도는 비선형계수로 정의되고, 그에 상응하는 강성에 의해 구해진다. 제안된 해석방법으로 비선형회전체, 비선형 베어링-페데스탈로 구성된 대형시계구조물의 진동을 해석하였다. 해석방법의 유효성을 평가하기 위해 응답의 정도와 계산소요시간을 유한요소법의 결과와 비교 분석하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.4
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• pp.439-446
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• 2014

This study introduces about the analysis, verification and implementation of Digital Communication Satellite transponder. Through the pre-performance analysis of each component by the circuit level simulation, each component's performance was checked whether satisfying the specifications. When each of the components was connected in order, System's performances were evaluated through system harmonic balanced simulation whether satisfying the specifications. Through pre-analysis of the system performance, specification of each component was defined. On the basis of that specification, Components which comprise the Digital Communication Satellite repeater were manufactured, and finally, the overall system performance check was made by integrating the components of Digital Communication Satellite transponder.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8A
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• pp.810-819
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• 2010

This paper proposes an algorithm to improve total network lifetime for Wireless Sensor Network (WSN) application such as environmental condition monitoring systems based on LEACH protocol. Firstly, the algorithm had equal number of nodes allocated to each cluster at cluster set-up phase where it abided by LEACH protocol. Secondly, at cluster set-up phase, each node was determined the order to be cluster header of the cluster which it had joined. After then, the role of a cluster head delivers to the next node according to determined order when the cluster head has received certain number of packets. With above method energy consumption of each node made equal and overall network lifetime was increased. Simulation results shows that overall network lifetime of proposed algorithm was increased two times than that of LEACH and total energy consumption was one forth of that of LEACH protocol.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.9
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• pp.974-978
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• 2003

The down-converter of the WCDMA Digital Optic Repeater is developed. Based on the system specifications, the structure of the down-converter is accomplished and its block diagram is drawn. The down-converter is implemented according to these block diagrams. Subsequently a low pass filter, an automatic level controlled attenuator, a frequency synthesizer and other components for the down-converter are designed and implemented, and a main board to integrate these modules is also manufactured. To reduce the noise floor of system and suppress the RF spurious noise, a PCB layout is performed carefully. For each module consisting of the down-converter and the entire system, the performance tests are accomplished to check the performance about the specifications.

• Information Systems Review
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• v.4 no.2
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• pp.237-255
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• 2002

In this study, we develop a four phase model of ERP implementation, which includes Chartering phase, Project phase, Shakedown phase, and Onward and upward phase. We then examine how the completeness of each phase influences the implementation success as well as the completeness of next phase. The results of this study show that project phase and onward and upward phase both have significant impacts on the implementation success. We also find that all relationships between the completeness of previous phase and next phase are significantly positive.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.65-70
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• 2013

In this paper, we propose a multi-hop cooperative transmission protocol to obtain energy savings in static wireless networks. Each terminal in the network is equipped with a single antenna and each receiver uses equal gain combining technique (EGC) to combine received signals. We also propose a power allocation strategy which optimizes the total transmit power at each stage. Monte-Carlo simulations are presented to evaluate and compare performance of the proposed protocol with the multi-hop direct transmission (MDT) and the cooperative routing protocol proposed by Khadani [8], in terms of the average total transmit power and the average number of required stages.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.599-602
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• 2016

실시간으로 뉴스 기사를 제공하는 온라인 뉴스 시스템이 널리 사용되면서, 사람들은 매 순간 속보와 새로운 뉴스 등 대량의 뉴스 기사에 노출되어 있다. 하지만 방대한 뉴스들로부터 사용자가 원하는 뉴스를 찾는 것은 매우 어려운 일이다. 따라서 개인 관심사에 따라 뉴스를 추천해주는 개인 맞춤형 뉴스 추천 시스템의 필요성이 증가되고 있다. 본 논문에서는 사용자의 관심사를 분석하여, 사용자의 관심사에 따라 관련된 뉴스를 자동으로 추천해주는 뉴스 추천 시스템을 설계 및 개발한다. 제안 시스템은 각 사용자가 북마크한 뉴스 기사와 읽은 뉴스 기사를 클러스터링하여 사용자별 프로파일을 생성한다. 또한 전체 뉴스 기사들을 클러스터링하여 주제 별로 분류한다. 사용자에게 뉴스를 추천하기 위해, 제안 시스템은 해당 사용자 프로파일에 포함된 각 클러스터에 대해 전체 뉴스 기사에 대한 클러스터들 중 가장 가까운 클러스터를 찾아 해당 클러스터 내의 뉴스 기사들을 거리 순으로 추천한다. 실제 구현된 시스템을 통해, 제안한 뉴스 추천 시스템이 각 개인에게 뉴스를 효과적으로 추천함을 보인다.