• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.12-19
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• 2022

Cathode open-type PEMFC (Proton Exchange Membrane Fuel Cells) stacks, which are widely used in small transport-type PEMFC, have a problem with poor durability. Through the accelerated durability test of the 13-cell PEMFC stack, we tried to find the cause of the degradation of the stack and to contribute to the improvement of the durability of the cathode open stack. A hydrogen/air boundary is formed during start-up/shut-down (SU/SD) due to the structural problem of the cathode open stack in which the cathode is open to the atmosphere and it is difficult to maintain airtightness, thereby deteriorating the cathode. In this study, it was possible to evaluate the durability in a relatively short time by reducing the 54% of the initial performance by repeating SU/SD 1,800 times on the cathode open stack. After dismantling the stack, each cell was divided into two and the performance was analyzed. Overall, the anode outlet MEA, which facilitates air inflow, showed more severe electrode deterioration than the inlet MEA, confirming that the hydrogen/air boundary formation during SU/SD is the main cause of degradation.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.11b
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• pp.636-639
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• 2002

광 인터넷의 개방형 인터페이스는 광 전달망과 제어 평면의 기술을 독립적으로 진화되게 하며 스위치의 구현을 단순화 시킨다. GSMP 프로토콜 기반의 개방형 인터페이스를 적용한 OBS 제어는 신호 프로토콜 및 GSMP 프로토콜의 실행 오버헤드로 인하여 연결설정의 지연을 증가시키는 단점이 있다. 본 논문에서는 GSMP 인터페이스를 이용하여 OBS 스위치를 제어하는 방안과 연결설정의 지연을 개선시키기 위하여 집중형 연결 서버를 이용한 병렬형 연결설정 메커니즘을 제안한다.

• The Korean Journal of Financial Studies
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• v.13 no.1
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• pp.133-160
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• 2007

본 연구는 중국 뮤추얼펀드를 대상으로 폐쇄형(48개), 개방형(17개)으로 구분하여 총 65개 펀드에 대해 성과를 측정해보고, 이를 통해 중국 뮤추얼펀드가 지수대비 어떠한 성과를 보여주고 있는지를 살펴보고자 한 연구이다. 성과 평가 실증기간은 폐쇄형 펀드가 2002년 1월 4일부터 2004년 12월 31일까지 3년으로 하며 개방형 펀드가 2003년 1월 3일부터 2004년 12월 31일까지 2년으로 하였다. 실증연구방법들은 CAPM에 기반한 트레이너 모형, 샤프 모형, 젠센 모형과 장세판단능력 측정 모형인 트레이너-마주이 모형이다.

• Bulletin of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.15-18
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• 1993

1970년대 초반부터 조선공업에 이용되기 시작한 CAD/CAM시스템은 설계단계에서 생산단계까지 그 사용이 보편화되고 있으며, 그 적용범위도 계속 넓어져 가고 있다.그러나 이들 CAD/CAM시스템들은 폐쇄형 구조를 가지고 있기 때문에 각종 설계관련 응용프로그램과의 접속에 어려움을 가지고 있다. 현재 개발되고 있는 CAD/CAM은 개방형 구조를 갖고, 기존환경과 접목이 가능한 통합시스템 개발로 나아가고 있다. 이 글에서는 최근 대두되고 있는객체지향기술을 실제 응용분야에 적용할 수 있고 개방형 구조를 갖는, 객체지향형 모델러인 AICS에 관해서 소개하였다.

• Journal of Technology Innovation
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• v.20 no.3
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• pp.199-228
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• 2012

While there are increasing requests for open innovation, prior studies have focused mainly on the utilizing the external sources. This study suggests to broaden the way of measuring openness to include the innovation management factors and output besides of utilizing the external sources. Additionally, the new measures will compare the status of openness in small and medium enterprises between Korea and Japan. There is greater differences in openness between SMEs and big firms in Japan than ones in Korea. Although SMEs in Japan utilize the external knowledge sources more actively than ones in Korea, they show less openness from the perspective of managerial factors such as metric for open innovation, collaboration system, investment for collaboration, and performance.

• Korean Security Journal
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• no.41
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• pp.213-240
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• 2014

How will South Korea design well-organized, open, and integrated counterterrorism system? Does this system work well in the emergent situation? These are very significant issues. It is likely that this system would give the solution. A legal basis needs to be established to have a well-organized, open, and integrated counterterrorism system. The core part of a well-organized, open, and integrated counterterrorism system is to minimize and eliminate damage caused by terror through preventiveness, preparation, action, and restoration. For having this system, they need to be divided into two section: an open one and an integration one. In this study, there will be a discussion on a new and appropriate counterterrorism system fit in South Korea a subordinate system: legal, organized, civil aspects need to be provided on the basis of an well-organized, open, and integrated counterterrorism system and an analysis on the current system of the States, England and the following implications.

• Journal of Korea Spatial Information System Society
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• v.11 no.1
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• pp.17-24
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• 2009

Recently many of earlier GIS services are changing to the form of user-participated dynamic geoweb service like many new impressive web 2.0 services substitute for earlier old-fashioned web 1.0 services. Many relevant technologies are necessary to be developed so as to integrate a number of geospatial data and functions all around into the useful geoweb services. It is also necessary to make the integration easy and to cope with the rapid changes in geoweb environment. In this study, the trend of relevant geoweb technologies were reviewed before, and the development of open geospatial service platform were carried out. As a result, open 2D/3D map service engine, user-participated mashup engine, Open API search engine and so on were im plemented as the core components of that platform. The platform will be able to be used as the common platform among a number of applications in the fields such as public/private GIS integration, u-city projects and GIS/LBS services etc.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.73-81
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• 2015

This research is designed to analyze the moderating effect of social capital between organizational slack and managerial practices for open innovation. After controlling the firm size, firm age, and environmental uncertainty, we test two hypotheses. First, we test the hypothesis that organizational slack has a positive effect on managerial practices for open innovation. Especially we focus on the managerial innovation and open innovation because recently managerial innovation and open innovation are more and more important. Second, we test the moderating role of social capital between organizational slack and managerial practices for open innovation. Because social capital is a kind of networking activity, we assume that social capital can contribute to managerial practices for open innovation through the networking activity. For this research, we administered the questionnaire surveys, and got the 250 effective data (companies) in Korea. Then we used the validity, reliability, correlation and multiple regression analysis by means of SPSS 18.0. As a result, we can find the two meaningful results. First, organizational slack, especially not absorbed slack but unabsorbed slack, has positive effect on managerial practices for open innovation. It is because absorbed slack such as excessive facilities, machines, or employees is not useful in managerial practices for open innovation. On the other hand, unabsorbed slack is useful in managerial practices for open innovation because unabsorbed slack such as excessive money or securities is very flexible and active. Taken together, the relationship between managerial practices for open innovation and unabsorbed slack is proven in terms of flexibility. Second, social capital has a moderating effect positively between organizational slack, especially not absorbed slack but unabsorbed slack, and managerial practices for open innovation. A prior study related to the relationship between managerial practices for open innovation and social capital doesn't exist yet, so this analysis result is very meaningful in academic respect. But this research has some limitations. First, this research is analyzed by limited region (Korea) and samples (250 companies), so more global regions and samples are recommended in the future. Second, we focus on managerial practices for open innovation in this paper, so the studies about technological practices for open innovation are recommended in the future.

• Journal of Science Education
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• v.36 no.2
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• pp.216-234
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• 2012

This study examined the characteristics of verbal interactions presented in TS activities with different tasks' openness levels by the cognitive levels of students through the implementation of TS program to 14 fifth graders in gifted class. Results of this study revealed that the open-type TS activities showed higher percentages of verbal interactions than the guiding-type TS activities showed and that the higher the open level of tasks was, the more high-level verbal interactions occurred. These results were showed in almost all subcomponents of verbal interactions. The results according to the students' cognitive levels showed that the higher the cognitive level of students was, higher frequency of interactions, high-level verbal interactions and a variety of verbal interactions occurred. The influence of both cognitive level of students and the task's openness on verbal interactions among students seemed to be interactive, however. In guiding-type activities, the percentage of high-level verbal interactions was not high although the cognitive level of students was high. And students in low level of cognition showed far lower frequency of interactions and their percentage of high-level verbal interactions was low even though the openness of the tasks was high. The results of this study meant that although open-type activities drew higher level verbal interactions by stimulating students' thought, the effects would be limited owing to their low cognitive level. Based on these findings, an implication was suggested that it is important to design instructional strategies and adjust openness level of TS activities to students' cognitive level so as to stimulate the thinking of students in lower cognitive level and to highten their engagement in activities.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.3 no.1
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• pp.46-55
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• 2004

방송과 통신이 융합됨에 따라 다양한 멀티미디어 서비스가 출현하고 있으며 가정에서도 다양하고 질 좋은 홈서비스에 대한 요구가 증대하고 있다. 이러한 다양한 홈 서비스 환경을 제공하기 위해 지능형 홈네트워크 플랫폼이 제안되고 구축되고 있으나 댁내부의 홈게이트웨이나 홈서버 등의 가입자 장치를 통한 응용 프로그램만으로는 다양한 서비스 제공에는 한계가 있다. 따라서, 외부에서 제공되는 다양한 디지털 홈서비스를 사용자에게 편리하고 안전하게 전달하고 사용자의 개입 없이 외부의 서비스 제공자가 개발한 홈서비스를 제공 수 있는 개방형 서비스 관리 구조가 요구된다. 본고에서는 다양한 홈서비스가 서비스 제공자로부터 사용자 장치에 분배, 운용, 관리될 수 있는 환경인 개방형 디지털홈 서비스 분배관리 체계를 소개하고, 홈네트워크 상의 서비스 사용자 뿐 아니라, 외부에서 댁내의 서비스를 이용하고자 하는 사용자에게 편리하고 안전하게 서비스를 제공할 수 있는 디지털 홈 서비스 플랫폼인 분배관리시스템 플랫폼을 제안한다.