• 한국자동차공학회논문집
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• 제7권9호
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• pp.36-47
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• 1999

Three-way catalyst converter, cleaning up the exhaust gas contamination of SI engine, has the best efficiency when A/F ratio is near the stoichiometry . The feedback control using oxygen sensors in the exhaust manifold has limits caused by the system delays. So the accurate measurement of air flow rate to an engine is essential to control the fuel injection rate especially on transient condition like the rapid throttle opening and closing. To measure the rapid change of flow rates. the air flow meter for the engine requires quick response, flow reversal detection, and linearity . Tjhe proposed integration type air flow meter (IFM), composed of an ultrasonic flow meter with an integration circuit, has significantly improved the measurement accuracy of air mass inducted through the throttle body. The proposed control method estimated the air mass at the cylinder port using the measured air mass at the throttle . For the fuel dynamic model, the two constant fuel model is introduced . The control parameters from air and fuel dynamics are tuned to minimize the excursion of the air fuel ratio. As a result A/F ratio excursion can be reduced within 5% when throttle rapidly opens and closes at the various engine conditions.

• Journal of Communications and Networks
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• 제4권4호
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• pp.321-335
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• 2002

Emergence of the fourth generation mobile communication system (4G system) is now in its dawn. This article proposes a perspective framework on the 4G system, and discusses various kinds of system aspects and technological requirements in terms of novel service features, spectrum management, radio access technologies, wired access integration, core network, and mobile terminal. The focus of the article is to define the scope and features of the 4G system in an overall system/network viewpoint. From the foreseeable development trends, it is highly expected that whatever emerges in the 4G system will be some kind of constantly evolving and grand recursive concatenation of all the existing system/network developments.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.17-20
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• 2008

HYOSUNG manufactured and tested 1kW class PEFC systems to generate electrical and thermal energy for each residential usage. In particular, HYOSUNG developed power conditioning system that performs over 91% electrical conversion ratio specified in 1kW class PEFC systems. Prior to system integration, we tested each performances of components to derive control issues from it. In addition, we have been developing the adequate simulator to describe and predict system performance. In this paper, we verified HYOSUNG's 1kW class PEFC systems are valid for residential energy sources by testing the characteristics of systems and performances of main components.

• 한국정보전자통신기술학회논문지
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• 제11권3호
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• pp.215-220
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• 2018

중견/중소 IT기업의 사업 수행 기회 증대, 기회 균등과 역량 강화라는 취지로 소프트웨어(SW)산업진흥법 개정으로 공공정보화시장에 대기업 참여를 제한되었다. 이러한 환경에서의 중견/중소 SW기업들의 사업을 수행하면서 발생한 사업 수행 역량 미흡으로 공공정보화사업의 품질저하, 위험관리 미숙, 일정관리 저하 등 여러 문제점을 발생시키고 있다. 이를 해결하기 위해 본 논문은 시스템통합 사업 수행 시 품질 저하 요인을 도출하였으며, 이를 해결하기 위한 방안으로 VISUALIZATION, 엄격한 시험관리, Agile방법론의 일부 활동을 적용하여 프로젝트를 수행하는 것을 제안했다. 이러한 방안을 중견/중소 IT기업이 개발한 보건의료 IT 프로젝트에 적용한 결과 의사소통의 개선, 수치화된 진척관리 및 프로젝트의 가시성이 개선되었다. 또한, 결함 해결시간 최소화, 요구사항 커리리지 비율 개선, 불필요한 회의시간이 단축이 되어 품질 향상에 기여하였습니다.

• 한국IT서비스학회지
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• 제18권2호
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• pp.75-96
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• 2019

These days, many companies use information systems as a basis for organizational management activities and as an important component of sustainable management. Thus, securing and operating a high-quality information system that can improve the efficiency of business processes is a large part of corporate competitiveness. In order to get such a critical information system, it is only possible to successfully carry out the project. Various attempts and studies have been undertaken to increase the success rate of the project. However, the reality is that the success rate is still not getting much better. In this study, the concept of quality of service, which has long been actively studied in marketing area, was applied as a new factor to enhance the project's success. In this study, project performance activities were defined as the act of providing services. A survey of 164 valid collection data was analyzed. The analysis used SPSS 23. Four process quality factors (customer participation, customer response, knowledge and skills, reliability) and 21 metrics were derived. Through this research, I hope to be the starting point of applying process quality concept as a new breakthrough to increase success rate of project.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1752-1756
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• 2003

Welding automation in shipbuilding process, especially in the assembly line is considered to be a difficult job because welding part is too huge , various and unstructured for a welding robot to weld the whole part automatically. We developed an automatic welding robot to improve those difficult process. This paper show how to systematically operate the integrated automation system which consists of several robots. We introduce our software and system integration method. Specially we focus that network communication and operating process. The developed system visualizes the operation environment using Open Inventor and communicates with the entire system via TCP/IP and FTP.

• 한국IT서비스학회지
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• 제5권1호
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• pp.129-147
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• 2006

This study analyzed an operational concept for the D Information Resource Management Information System (DIRMIS) to manage any IT resources effectively in defense area. We first deduced the concept of the information resource management (IRM) for defense area from the literature review, and we suggested a guideline, which has used in defense area, of the documentation for the operational concept description (OCD). Moreover, we developed the operational concept for the DIRMIS following the guideline. Especially, this study is a practical approach for suggesting of a case, and the share of accumulated cases will contribute to advance in System Integration (SI) industry as well as academic research.

• 융합보안논문지
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• 제5권3호
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• pp.15-22
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• 2005

인터넷의 보급과 다운사이징, SI 기법이 등장하면서 기존의 집중식 컴퓨팅은 급격히 분산 컴퓨팅으로 변하고 있다. 또한 분산 컴퓨팅은 유선으로 연결된 네트워크에서 벗어나 유비쿼터스 컴퓨팅으로 빠르게 변화하고 있다. 점차 복잡해지는 이기종 환경에서 용융 프로그램과 운영체제에 원만한 통신을 이룰 수 있게 하는 미들웨어로 CORBA가 널리 사용되고 있다. 그러나 지능적이고 다양화되는 공격들(해커, 바이러스, 웜 등) 속에서 분산처리 환경은 절대 안전할 수 없는 것이 현실이다. 본 논문에서는 OMG에서 제시한 CSS를 기반으로 유비쿼터스 환경에 적합한 DB보안 모델을 설계하고 기존 모델과 비교 분석하여 효율성을 제시하고자 한다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.188-188
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• 2011

Recently, scaling down of ULSI (Ultra Large Scale Integration) circuit of CMOS (Complementary Meta Oxide Semiconductor) based electronic devices, the electronic devices, become much faster and smaller size that are promising property of semiconductor market. However, very narrow interconnect line width has some disadvantages. Deposition of conformal and thin barrier is not easy. And metallization process needs deposition of diffusion barrier and glue layer for EP/ELP deposition. Thus, there is not enough space for copper filling process. In order to get over these negative effects, simple process of copper metallization is important. In this study, Cu-V alloy layer was deposited using of DC/RF magnetron sputter deposition system. Cu-V alloy film was deposited on the plane SiO2/Si bi-layer substrate with smooth surface. Cu-V film's thickness was about 50 nm. Cu-V alloy film deposited at $150^{\circ}C$. XRD, AFM, Hall measurement system, and AES were used to analyze this work. For the barrier formation, annealing temperature was 300, 400, $500^{\circ}C$ (1 hour). Barrier thermal stability was tested by I-V(leakage current) and XRD analysis after 300, 500, $700^{\circ}C$ (12 hour) annealing. With this research, over $500^{\circ}C$ annealed barrier has large leakage current. However vanadium-based diffusion barrier annealed at $400^{\circ}C$ has good thermal stability. Therefore thermal stability of vanadium-based diffusion barrier is desirable for copper interconnection.

• 한국컴퓨터정보학회논문지
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• 제15권7호
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• pp.109-116
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• 2010

본 연구에서는 계열 IT서비스 기업을 갖는 국내 대형 그룹사의 IT수준과 IT서비스 기업의 성과에 대한 관련성을 실증적으로 분석하였다. 총 24개 IT서비스 기업과 관련 그룹사를 대상으로 한 연구에서, 관련 가설을 수립하여 집단간 차이분석(t-test)을 통해서 통계적으로 검증하였다. 그 결과, IT서비스사의 SM 매출과 대내 매출, 대내 서비스 역량 및 종합 서비스 역량 그리고 그룹사 자체의 매출액 및 IT 서비스 신규투자 규모가 고객 그룹사의 IT수준에 영향을 주는 것으로 나타났다. 또한 고객 그룹사의 매출, IT서비스 기업의 대내 및 SM 매출이 높은 집단에서 IT서비스 기업의 매출액이 높게 나타났으며, 대외 사업 비중 및 SI 사업 비중이 낮은 집단과, 대내 사업 비중 및 SM 사업 비중이 높은 집단에서 IT 서비스 기업의 서비스 역량이 높게 나타났다.