• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.716-719
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• 2009

HFC-134a 의 농도별(99.9%, 80%, 50%, $N_2$ balance)로 하이드레이트의 결정생성/해리 특성을 연구하였다. HFC-134a 하이드레이트는 기/액 경계면에서만 수지상 형태의 하이드레이트 결정이 생성되었으며 수용액 내의 하이드레이트 결정관찰을 위해 물리적인 방법을 이용하였다. HFC-134a 농도가 낮을수록 하이드레이트 결정생성 속도가 둔화되었으며 특히 $N_2$의 함량이 50% 이상일 경우 $N_2$가 확연히 inhibitor 역할을 하였다. 하이드레이트 해리 시에는 기/액 경계면과 수용액 내부에서 매우 다른 양상이 관찰되었으며 하이드레이트 결정이 분해되면서 동공 속에 포집되었던 가스가 방출되는 것을 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.395-398
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• 2009

전기도금 방법을 사용해 각기 다른 환원 전압과 전기도금시간에서 Pd 수지상 나노와이어(Pd DNWs) 전극이 합성 되었으며 그 성장 기작을 논의하였다. 전기화학적인 도금 공정 동안 Pd DNWs 이<111>방향으로 성장하는 것을 확인할 수 있었는데, 이것은 전해질 속의 황산음이온들이 Pd 의 (111)면에 흡착하기 유리하기 때문이라고 사료된다. 가해준 환원전압이 증가함에 따라, 단 결정 수지상의 나노와이어의 가지는 길어지고 얇아지는 경향을 보였다. 이것은 전기도금 시간이 아니라 환원전압에 의해서만 나노와이어 가지의 직경이 조절됨을 보여준다

• New & Renewable Energy
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• v.3 no.1 s.9
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• pp.20-26
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• 2007

A low-resolution national wind map, which is a prerequisite for setting up the national dissemination target and strategy of wind energy development, has been established by numerical wind simulation using the synoptic wind map, developed at the first stage, as an upper boundary condition. Based on the wind map, Wind Resource Information System has been composed in order to support scientific and systematic wind resource assessment and analysis.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.827-830
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• 2003

인터넷의 등장과 통신기술의 발달로 인해 여러 분야에서 원격 교육이 이루어지고 있다. 이러한 결과로 인해 다양한 멀티미디어 기술을 활용한 컨덴츠의 저작이 일반화되고 있다. 이러한 컨텐츠는 전통적인 교실 수업과 같은 학습 효과를 얻기 위해 상호작용 적인 멀티미디어 컨텐츠를 도입하는 노력을 기울이고 있지만 아직 기능상에 많은 제약이 있다. 원격 교육을 위한 강의를 작성하기 위해서 강의자는 관련 프로그래밍 기술 등을 익혀야 하므로 상당한 관련 지식이 요구되어 가상강좌를 개설하기가 어려운 실정이다. 본 논문은 이러한 어려움을 해결하기 위하여 강의자와 학생의 학습을 효과적으로 지원하는 가상 강의 저작도구를 설계 및 구현함으로써 프로그래밍 지식이 없는 초보자도 윈도우 기반의 메뉴방식으로 정보 입력을 통해 교수의 강의와 학생의 학습을 효과적으로 지원하는 가상 강의 구축이 이루어 질 수 있도록 JVM(Java Virtual Machine)환경에서의 강의저작 및 재생 시스템 구현에 관한 논문이다. 이 시스템은 교수 강의 저작 도구를 구현하고, 수강생 개개의 학습이 가능하도록 저작된 강의를 재생함을 목적으로 하고있다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.99.1-99.1
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• 2011

Reactant mixing has a critical role in ensuring reformate quality and an important design objective is to achieve sufficiently complete mixture of reactants. For that purpose it is required to understand the coupled transport-kinetics phenomena in the mixing region. Three-dimensional computational fluid dynamics model was developed and validated in previous works. The mixing characteristics in various alternatives of a prototype mixing chamber were compared, and then a reduced reaction kinetics was applied to two extreme designs for investigating the impact of gas-phase reactions. Both designs did not reach threshold ethylene mole fraction of 0.001, but surprisingly more ethylene was generated in the design having better mixing characteristics. The presentation will deliver the development process of coupled transport and kinetics model briefly and the detailed information about the mixing characteristics and gas-phase reactions in two mixer designs.

• Proceedings of the Korea Multimedia Society Conference
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• 2004.05a
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• pp.306-309
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• 2004

MPEG 비디오 스트림의 시간적 차원과 색상적 차원을 고려하여 모두 4 단계의 해상도가 구성되는 엔코딩 기법과 디스크 배열에 대한 스트라이핑 기법이 본 논문에서 제시된다 먼저 MPEG-1 스트림은 I 프레임과 P 프레임으로 구성된 서브스트림과 B 프레임만으로 구성된 서브스트림으로 분할된다. 분할된 서브스트림의 각 프레임은 색상 차원에서 저해상도용 컴포넌트와 고해상도용 컴포넌트로 다시 분리된다 따라서 한 MPEG 비디오 스트림은 4 개의 컴포넌트로 구성되며 각 컴포넌트를 구성하는 블록들이 디스크 배열에 연속적으로 저장되는 스트라이핑 기법이 기술된다. 즉 4 개의 컴포넌트가 모두 재생될 경우 해상도가 가장 높게 나타나며 재생되는 컴포넌트의 수가 1 개씩 감소될수록 1 단계씩 낮은 해상도가 유지된다. 4 단계의 해상도를 구성하는 본 논문의 엔코딩 기법과 디스크 배열을 위한 스트라이핑 기법은 멀티미디어 서버의 성능을 향상시킬 수 있으며 이에 대한 시뮬레이션 결과가 기술된다.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.1
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• pp.167-177
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• 2008

The Urban Regeneration can improve physical, environment, economy, life and culture of retarded urban area to recover vitality and to recreate residing environment having competitiveness. This study constructed buildings database to investigate deterioration of buildings of each dong that was minimum administrative region classified for administrative convenience, and spatial structure analysis for Urban Regeneration in Busan. Legal standards have not been established yet. Therefore, the study conducted quantitative analysis based on the Law of Urban and Dwelling Environment Improvement as well as the Special Law of Promotion of Urban Reorganization to find out problems of existing legal systems and to make use of investigation results as basic material of Urban Regeneration project in the future. And, the study investigated physical deterioration of buildings, and characteristics and types of the variables such as population, welfare, business entities at each dong, that is to say, basic administration unit of the government through Factor-Analysis.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.74-81
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• 2008

Urban Regeneration has an object to restore a function of urban through physical/cicumstance, social lift/culture, industrial/economic regeneration. It has characteristics like existence of a lot of projects, complextity of stakeholders' structure, long period of project life cycle to achieve variety of project's promotion strategy. To accomplish a Urban regeneration that has above characteristics successfully, information about other projects should be managed organically. And it should provie information linked up with each projects by integrated management. We need a decision making method that helps users cope with requirements of change during project, and offers information when each users need to make a decision timely. So I propose a strategy to build the IETM considering urban regeneration characteristics.

• Journal of the Korean Regional Science Association
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• v.37 no.3
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• pp.47-58
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• 2021

In 2010, Busan Metropolitan City established an organization dedicated to urban regeneration. The Sanbok Road Renaissance Project and Hope Village Project are representative urban regeneration projects. Busan Metropolitan City is a leading local government that has expanded community business through urban policies. This study analyzed the operational status and characteristics of community-based community businesses based in Busan Metropolitan City in the early stages of urban regeneration policy. As a result, the direction of community-based community business is 'community empowerment'. However, the project effects such as 'expansion of opportunities for local residents to help each other' and 'residents' understanding of the local community' were low. In order to operate a community business, it is important to secure sufficient business capital and secure necessary human resources. In order to revitalize community-based community businesses through urban regeneration policies, it is necessary to convert support into functional organizations of urban regeneration projects rather than expanding subsidies and expand opportunities for business participation.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1002-1007
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• 2012

The considerable portion of energy demand has been satisfied by the combustion of fossil fuel and the consequent $CO_2$ emission was considered as a main cause of global warming. As a technology option for $CO_2$ emission mitigation, absorption process has been used in $CO_2$ capture from large scale emission sources. To set up optimal operating parameters in $CO_2$ absorption and solvent regeneration units are important for the better performance of the whole $CO_2$ absorption plant. Optimal operating parameters are usually selected through a lot of actual operation data. However theoretical approach are also useful because the arbitrary change of process parameters often limited for the stability of process operation. In this paper, a theoretical approach based on vapor-liquid equilibrium was proposed to estimate optimal operating conditions of $CO_2$ absorption process. Two $CO_2$ absorption processes using 12 wt% aqueous $NH_3$ solution and 20 wt% aqueous MEA solution were investigated in this theoretical estimation of optimal operating conditions. The results showed that $CO_2$ loading of rich absorbent should be kept below 0.4 in case of 12 wt% aqueous $NH_3$ solution for $CO_2$ absorption but there was no limitation of $CO_2$ loading in case of 20 wt% aqueous MEA solution for $CO_2$ absorption. The optimal regeneration temperature was determined by theoretical approach based on $CO_2$ loadings of rich and lean absorbent, which determined to satisfy the amount of absorbed $CO_2$. The amount of heating medium at optimal regeneration temperature is also determined to meet the difference of $CO_2$ loading between rich and lean absorbent. It could be confirmed that the theoretical approach, which accurately estimate the optimal regeneration conditions of lab scale $CO_2$ absorption using 12 wt% aqueous $NH_3$ solution could estimate those of 20 wt% aqueous MEA solution and could be used for the design and operation of $CO_2$ absorption process using chemical absorbent.