• Title/Summary/Keyword: Technology-oriented

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Interactive Teaching and Self-Study Tools for Power Electronics

  • Ertugrul, Nesimi
    • Journal of Power Electronics
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    • v.2 no.4
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    • pp.258-267
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    • 2002
  • This paper presents the principal features of the software modules developed to provide an interactive teaching/learning environment in Power Electronics that can be used by educators and students. The software modules utilize an object oriented programming LabVIEW that provides a highly flexible graphical user interface. The paper highlights the principal features the software components and illustrates a number of highly interactive graphical user interfaces of selected Power Electronics circuits and systems.

Highly Thermal Conductive Alumina Plate/Epoxy Composite for Electronic Packaging

  • Jeong, Un Seong;Lee, Yoon Joo;Shin, Dong Geun;Lim, Hyung Mi;Mun, So Youn;Kwon, Woo Teck;Kim, Soo Ryong;Kim, Young Hee;Shim, Kwang Bo
    • Transactions on Electrical and Electronic Materials
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    • v.16 no.6
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    • pp.351-354
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    • 2015
  • In this study, alumina plates 9~25 μm in size were used as thermal fillers, and epoxy resin was used as a polymer matrix. Oriented alumina plate/epoxy composites were prepared using a rolling method. The effect of ordering alumina plates increased with alumina plate size. The thermal conductivity and flexural strength of the composites were investigated. The horizontal thermal conductivity of the oriented composite was significantly higher than the vertical thermal conductivity. The horizontal thermal conductivity of the 75 wt% alumina content was 8.78 W/mk, although the vertical thermal conductivity was 1.04 W/mk. Ordering of the alumina plate using a rolling method significantly improved the thermal conductivity in the horizontal direction. The flexural strengths of the ordered alumina/epoxy composites prepared at different curing temperatures were measured.

Preparation and Pervaporative Alcohol Dehydration of Crystallographically b/c-axis Oriented Mordenite Zeolite Membranes (결정학적으로 b/c-축 방향으로 배향된 모데나이트 제올라이트 분리막의 제조 및 투과증발 알코올 탈수 거동)

  • Kim, Young-Mu;Lee, Du-Hyoung;Kim, Min-Zy;Cho, Churl-Hee
    • Membrane Journal
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    • v.28 no.5
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    • pp.340-350
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    • 2018
  • In the present study, crystallographically b- and c-axis oriented mordenite zeolite membranes were prepared and their pervaporative ethanol dehydration was investigated. The seed layer with a high coverage grew to be c-axis oriented dense layer, while the seed layer with a low coverage grew to be b-axis oriented layer. This phenomenon could be explained by the evolutionary selection growth mechanism. The b-axis grown membrane with 8-membered rings showed a high separation factor of above 1000 and a considerable total flux of around $0.2kg/m^2h$. The c-axis grown, columnar structured membrane with 8- and 12-membered rings showed a low separation factor of less than 200 and a relatively high total flux of around $0.25kg/m^2h$. The high performance of b-axis grown membrane was due to the relatively small opening of 8-membered rings. Water molecules can freely permeate through the openings, but ethanol molecules, difficultly. Therefore, in the present study, we introduced a new method to control crystallographic orientation of mordenite membrane by changing seeding amount of needle-like crystals, and elucidated that b-axis oriented mordenite membrane showed better performance than c-axis grown mordenite membrane.

Grain orientation distribution of the ZrB $_{2 }$ - ZrCcomposite sintered by the different sintering technique (소결방법에 따른 ZrB $_{2 }$ - ZrC 복합체에서의 결정립 방위 분포의 변화)

  • ;Y. Yasutomi;Y. Takigawa;H. Yanagida
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.2
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    • pp.152-158
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    • 2000
  • The crystallographic grain orientation of {{{{ { ZrB}_{2 } }}}}-ZrC composite sintered by pressureless a sintering(PLS) and spark plasma sintering (SPS) was analysed by the SEM-EBSP technique. In the case of PLS, (160) plane of {{{{ { ZrB}_{2 } }}}} was oriented to ND direction, (101) and (111) plane of ZrC were oriented to ND direction. In the case of SPS, (0001) plane of {{{{ { ZrB}_{2 } }}}} was strongly oriented to ND direction. Only (001) plane of ZrC was oriented to ND direction. The PLS specimen had weakly oriented grain structure and interface between {{{{ { ZrB}_{2 } }}}} and ZrC was found to be more stable than that of SPS but the SPS specimen had a preferentially oriented grain structure.

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Model-Based Quantitative Reengineering for Identifying Components from Object-Oriented Systems (객체지향 시스템으로부터 컴포넌트를 식별하기 위한 모델 기반의 정량적 재공학)

  • Lee, Eun-Joo
    • The KIPS Transactions:PartD
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    • v.14D no.1 s.111
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    • pp.67-82
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    • 2007
  • Due to the classes in object-orientation, which are too detailed and specific, their reusability can be decreased. Components, considered to be more coarse-grained compared to objects, help maintain software complexity effectively and facilitate software reuse. Furthermore, component technology becomes essential by the appearance of the new frameworks, such as MDA, SOA, etc. Consequently, it is necessary to reengineer an existing object-oriented system into a component-based system suitable to those new environments. In this paper, we propose a model-based quantitative reengineering methodology to identify components from object-oriented systems. We expand system model and process, which are defined in our prior work, more formally and precisely. A system model, constructed from object-oriented system, is used to extract and refine components in quantitative ways. We develop a supporting tool and show effectiveness of the methodology through applying it to an existing object-oriented system.

Transition Experiment and Socially-oriented R&D Program (시스템 전환론의 관점에서 본 사회문제 해결형 연구개발사업의 발전 방향)

  • Song, Wichin;Seong, Jieun
    • Journal of Technology Innovation
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    • v.22 no.4
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    • pp.89-116
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    • 2014
  • Socially-oriented R&D programs aimed at solving societal problem rather than scientific and industrial fruits have started recently. Societal problem is recognized as dilemma since this problem related to various stakeholders. And this is not solved with single program and needed long-term process. So the perspective of socio-technical system transition including technological and institutional change is needed. This paper suggests policy implication of Socially-oriented R&D programs from socio-technical system transition perspective. 'Transitioning of Socially-oriented R&D program' is the key concept of restructuring the program for the system transition. The establishment of multi-layer transition governance and the transition vision-making and transition experiment planning are the key process of transitioning the R&D program. This paper suggests the ways and issues of implementing this process in Socially-oriented R&D program.

Contingent Analysis of the Relationship between Evaluation type and MIS Performance (MIS 평가 유형과 MIS 성과 간의 상황적 관계에 관한 연구)

  • Chung, Moon-Sang
    • The Journal of Information Systems
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    • v.13 no.2
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    • pp.225-240
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    • 2004
  • The most critical problem of MIS evaluation is the lack of the systematic framework to cover various factors and viewpoints. To solve this problem, this study takes the multi-level and contingent approach to performance evaluation, composed of three levels: evaluating the contribution of MIS to an organization [strategy level]; evaluating the activities of MIS department or MIS function as an organizational sub-function through the overall MIS lifecycle [function level]; and evaluating the quality or productivity of the application systems as MIS outputs [system level]. Ideal MIS evaluation should include all three levels of the hierarchy with balanced importance. However, MIS evaluationcanbedividedintothreetypes,suchasstrategy-oriented, function-oriented and system-oriented evaluation, depending on the focus and emphasis of evaluation. The usage pattern of each evaluation type is analyzed according to contingent variables of MIS evaluation such as MIS maturity, information intensity and firm size, and top management's intent. It is also found that the firms of higher MIS maturity and top management's intent use the strategy-oriented evaluation type, and the firms with strategy-oriented evaluation type show a higher MIS performance. Further, MIS maturity and top management's intent show contingent effects between evaluation type and MIS performance. Some managerial implications can be drawn based on the results of the study. First, strategy-oriented evaluation of MIS is more important as many firms more often use information technology as a strategic weapon. Second, MIS performance varies with evaluation type. Therefore, the design of MIS evaluation framework should be done carefully in the strategic and managerial contexts. Third, firms are recommend to use a different evaluation type according to organizational characteristics such as MIS maturity and information intensity.

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VOQL : A Visual Object Query Language (Stochastic VOQL : 시각적 객체 질의어)

  • Kim, Jeong-Hee;Cho, Wan-Sup;Lee, Suk-Kyoon;Whang, Kyung-Young
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.5
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    • pp.1-15
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    • 2001
  • Expressing complex query conditions in a concise and intuitive way has been a challenge in the design of visual object-oriented query languages. We propose a visual query language called VOQL (Visual Object oriented Query Language) for object oriented databases. By employing the visual notation of graph and Venn diagram, the database schema and the advanced features of object oriented queries such as multi-valued path expressions and quantifiers can be represented in a simple way. VOQL has such good features as simple and intuitive syntax, well-defined semantics, and excellent expressive power of object-oriented queries compared with previous visual object-oriented query languages.

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