• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.440-440
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• 2012

Nanomaterials have emerged as new building blocks to construct light energy harvesting assemblies. Size dependent properties provide the basis for developing new and effective systems with semiconductor nanoparticles, quantized charging effects in metal nanoparticle or their combinations in 2 and 3 dimensions for expanding the possibility of developing new strategies for photovoltaic system. As top-down approach, we developed a simple and effective method for the large scale formation of self-assembled Cu(In,Ga)$Se_2$ (CIGS) nanostructures by ion beam irradiation. The compositional changes and morphological evolution were observed as a function of the irradiation time. As the ion irradiation time increased, the nano-dots were transformed into a nano-ridge structure due to the difference in the sputtering yields and diffusion rates of each element and the competition between sputtering and diffusion processes during irradiation. As bottom-up approach, we developed the growth of CIGS nanowires using thermal-chemical vapor deposition (CVD) method. Vapor-phase synthesis is probably the most extensively explored approach to the formation of 1D nanostructures such as whiskers, nanorods, and nanowires. However, unlike binary or ternary chalcogenides, the synthesis of quaternary CIGS nanostructures is challenging because of the difficulty in controlling the stoichiometry and phase structure. We introduced a method for synthesis of the single crystalline CIGS nanowires in the form of chalcopyrite using thermal-CVD without catalyst. It was confirmed that the CIGS nanowires are epitaxially grown on a sapphire substrate, having a length ranged from 3 to 100 micrometers and a diameter from 30 to 500 nm.

• 대한교통학회지
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• 제35권1호
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• pp.37-49
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• 2017

본 연구에서는 도로이동오염원을 대상으로 추진하는 교통환경정책의 대기질 개선효과 분석 방법론을 제시하였으며, 해당 방법론은 정책 추진에 따른 도로이동오염원의 통행량과 대기오염물질 배출량 변화, 대기오염물질의 공간적 확산과 이로 인한 노출인구의 건강영향을 순차적으로 고려한다. 특히 도로이동오염원의 통행량 변화는 정책 효과와 직접적인 연관이 있기 때문에 대기질 개선효과 분석시 반드시 고려되어야 하며, 본 연구에서는 교통수요모형 기반의 상향식 방법을 적용하여 기존 하향식 방법 대비 정책 추진에 따른 통행자의 통행행태 변화를 상세하게 반영하고자 하였다. 정책 시나리오 분석을 통하여 본 연구에서 제시한 분석 방법론의 활용가능성을 검토하였으며, 통행자의 통행행태 변화가 예상되는 정책의 대기질 개선효과 분석은 본 연구의 분석 방법론 적용이 필요한 것으로 판단된다.

• 인터넷정보학회지
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• 제14권3호
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• pp.68-77
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• 2013

This article consists of 3 parts. Part I is multi stakeholder approach on Internet governance system. Part II is analysis of the Korean Internet governance system. In this part, I explain relevant laws in Korea, including Korean Internet Address Resources Act. Part III is my suggestion on Korean Internet governance system using a multi stakeholder approach. First of all, the keyword of the Internet governance system is decision making process: that is, consensus based versus top-down approach. Then who are major players in Internet governance in national level? Government, or Private sectors such as business and civil society. Korean legal system for Internet governance shows a top-down decision making process. Major players are the government (that is, Ministry of Science, ICT and Future Planning) and KISA affiliated with the government. Other players include Internet Address Policy Committee, Korea Internet Governance Alliance, and NGOs. The key statute for Internet governance in Korea is Internet Address Resources Act of 2004. Articles 3 and 5 require the Ministry of Science, ICT and Future Planning to take a proactive role in Internet governance. The government shall consult with the Internet Address Policy Deliberation Committee for Internet governance. Yet this Committee is established under the control of the Ministry of Science, ICT and Future Planning. All members of this Committee are also commissioned or nominated by the Chairman of the Ministry. Meanwhile, there are also non-official organizations, including Sub-committee on Address & Infrastructure of Korea Internet Governance Alliance. I suggest to reform decision making process of Korean Internet governance system based on BOTTOM-UP process for CONSENSUS BASED DECISION. My suggested system includes the following: (1) The government hands over a major role in Internet governance to INDEPENDENT Internet policy organization. And the government participates in such organization as ONE of the players. (2) Nomination of this committee member must be bottom-up process for a genuine multi-stakeholder model including civil society, commercial organization, end-users and experts. (3) The government should establish plan for supporting the private sector's international activity on the long-term basis.

• 디지털융복합연구
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• 제13권1호
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• pp.227-235
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• 2015

빅데이터분석은 조직의 문제해결을 위한 융합적 수단이다. 효과적인 문제해결을 위해서는 문제의 형태, 데이터의 유형 및 존재여부, 데이터 분석역량, 분석을 위한 기반정보기술의 수준 등 다양한 요인을 융합적으로 고려하여 문제해결의 접근법이 결정되어야 한다. 본 연구에서는 기획 접근법으로 논리적인 하향식 접근법, 데이터기반의 상향식 접근법, 그리고 문제해결 환경의 불확실성을 극복하기 위한 프로토타이핑 접근법 등 세 가지 유형을 제안한다. 특히, 이 유형 중에서 창의적 문제해결과 상향식 접근법이 어떤 연관성을 갖는지 살펴본다. 또한 데이터 거버넌스와 데이터 분석역량을 융합적으로 고려하여 조직의 빅데이터분석의 소싱과 관련한 주요 전략적 이슈를 도출한다.

• 한국항공운항학회지
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• 제19권2호
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• pp.52-57
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• 2011

The procedures of Continuous Descent Approach(CDA) is designed to minimize the thrust required during landing, thereby reducing fuel consumption, noise and emissions compared to conventional approach procedures. Widespread implementation of CDA would result in significant reductions in the environmental impact and aircraft operation costs. This paper estimated the possible economic effects from the perspective of airliners through cost-benefit analysis, provided that the CDA is introduced. It is now proposed that a more comprehensive analysis model, which includes the reduced ATC communication burden between controllers and pilots, not to mention the economic aspect, should be established for the improvement.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.48-48
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• 2011

We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.

• 농촌지도와개발
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• 제24권2호
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• pp.143-154
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• 2017

본 연구의 목적은 라오스 정부가 농업 농촌 발전을 목적으로 2012년부터 국가 정책으로 추진하고 있는 삼상(Sam Sang, 정치적 실천공약, 분산-분권, 국가적 목표) 농촌발전 프로그램을 소개하고, 한국의 1970년대 새마을운동의 교훈을 분석하여, 라오스 삼상모델에 적용할 수 있는 가능성을 제시하는 것이다. 본 연구의 결과 라오스 정부가 추진하고 있는 삼상 농촌개발정책에 적용할 수 있는 교훈을 다음과 같이 제시하고 있다. 상-하향식의 통합적 개발 접근은 한국 농촌발전에 매우 중요한 영향을 미친 것으로 평가하고 있으며, 놀라운 정책결과를 가져온 요인으로 분석하고 있다. 그리고 주민참여의 중요성을 부각하고 있으며 정책을 집행하는 초기단계에는 마을과 마을주민들의 역량강화를 위해서 정부의 적절한 개입과 역할을 강조하며 이를 통한 주민참여를 유도하여 궁극적으로는 자립적 의지를 통한 지속가능한 농촌개발접근이 되어야 한다고 주장하고 있다.

• 공학교육연구
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• 제6권2호
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• pp.22-29
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• 2003

하드웨어 설계 교육의 궁극적인 목표는 학생들로 하여금 시스템 설계능력을 갖추도록 배양하는 데에 있다. 그러나 상당수의 기존 교과과정은 설계 자체보다는 개별적인 빌딩 블록의 내부동작 원리의 이해를 중심으로 운영되는 것이 현실이다. 따라서, 학생들의 학습동기 유발에 실패할 뿐만 아니라 정작 현장에서 필요로 하는 시스템적 관점에서의 설계를 충분히 경험하지 못하는 것이 문제점으로 지적된다. 이러한 문제점들을 극복하기 위한 대안으로, 과목의 초기 도입부에 추상화의 수준을 높여서 시스템의 전체 설계를 조망할 수 있도록 하고, 점차로 추상화의 단계를 낮추어서 결국 소자의 동작 원리를 탐구하는데 이르도록 강의의 순서를 역전시킬 필요성이 있다. 본 논문에서는 하드웨어 설계의 입문 과목인 논리설계 교과목을 대상으로 하여, 시스템 수준의 설계표현 및 검증방식을 먼저 소개하고 소자에 대한 세부지식은 후반부에 소개하는 새로운 교육방식을 제안하고 이의 타당성을 검증하기 위해 교내의 동아리를 활용한 비정규 교육과정에 이를 도입한 사례를 소개한다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제21권1호
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• pp.1-11
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• 2018

The emergence of mucosal healing as a treatment goal that could modify the natural course of Crohn's disease and the accumulating evidence showing that biologics are most effective in achieving mucosal healing, along with the success of early treatment regimens for rheumatoid arthritis, have led to the identification of early Crohn's disease and development of the concept of catching the therapeutic window during the early disease course. Thus, an increasing number of pediatric gastroenterologists are adopting an early biologic treatment strategy with or without an immunomodulator. Although early biologic treatment is effective, cost and overtreatment are issues that limit its early use. Currently, there are insufficient data on who will benefit most from early biologics, as well as on who will not need early or even any biologics. For now, top-down biologics should be considered for patients with currently known high-risk factors of poor outcomes. For other patients, close, objective monitoring and accelerating the step-up process by means of a treat-to-target approach seems the best way to catch the therapeutic window in early pediatric Crohn's disease. The individual benefits of immunomodulator addition during early biologic treatment should be weighed against its risks and decision on early combination treatment should be made after comprehensive discussion with each patient and guardian.

• 한국해양공학회지
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• 제12권3호통권29호
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• pp.86-95
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• 1998

CAD/CAM program developers have made substantial progress in enabling engineers to design, analyze, visualize, visualize, and simulate the performance of structures and systems. Many researchers, however, agree that there is still a way to go before the existing commercial computer software can be used in ship structural analysis to their full potential as solvers which can identify opportunities to reduce man-hours and cut costs. CAD systems used for these works in ship yards are general-purposed and not custom-tailored for ship structures, which force end-users to do tiresome and routine works. The new preprocessor "MeshGen" announced in this study can load several ship types and user-friendly generate their FE meshes employing the object-oriented approach based on the parametric and top-down design. Also "MeshGen" reduces dramatically the time required to prepare CAD models under window-based environments on desktop personal computers and makes it much easier and faster for end-users to change topology and material properties.