• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.505-518
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• 2005

풍력발전기술은 전적으로 바람의 세기에 의존하는 신재생에너지원으로서 바람의 강도가 발전전력의 양과 풍력시스템의 효용성에 절대적인 영향을 미치게 된다. 따라서, 본 연구사업을 통해서 이루어지는 풍력자원의 조사는 풍력발전기술의 적용에 앞서 최우선적으로 수행되어야 함이 본 연구사업의 중요성이라 할 수 있다. 풍력자원에 대한 실측자료로서 풍력자원 특성의 분석이 가능하고 이에 따라 풍력발전기의 용량 및 수량과 적용방안 및 최종적으로 정량적인 의미에서의 경제성 분석도 가능하게 되었다. 본 연구에서는 장차의 본격적인 풍력발전기술의 적용에 앞서 기존 기상청의 풍력자료와 일정한 기준에 의하여 선정된 후보지점을 중심으로 도상검토 및 실사를 통해 1차년도에 9군데, 2차년도에 6군데 총 15개 지점에 대한 실측지점을 선정하여 실측기기의 설치와 풍력자료의 분석으로서 정밀한 풍력자원의 특성을 분석하고 향후 본격적인 풍력발전 단지 건설 사업추진에 대비하고자 수행된 연구사업이며, 아울러 개괄적인 국내 풍력자원 분포를 파악하기 위한 광역 풍력자원 분포도를 개발하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.116-125
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• 1995

우리나라 에너지소비구조는 높은 화석연료 의존성, 에너지 다소비형 산업구조, 열악한 에너지소비효율성 등 구조적 취약성을 지니고 있다. 특히 국내 총 에너지 수요의 60 % 이상을 차지하는 석유는 전량 해외수입에 의존하고 있어 향후 석유위기 상황 재연시 국가 전체 산업활동을 위축시킬 수 있는 가능성을 내포하고 있다. 정부에서는 국내외 사회/경제적 환경변화에 부응하고 국가경제의 지속적 발전을 위해 에너지 및 자원개발전략 내용을 포함한 신경제 5 개년계획을 수립한 바 있으며, 신재생에너지 개발기술의 조기 실용화 및 보급확대를 위하여 연료용알콜 생산 기술개발을 중점추진하고 있다. 특히 최근 지구온난화 문제와 관련하여 국가간 탄소배출규제협약 (Green Round)의 발효가 예견되는 상황에서 청정/재생에너지로서 연료용알콜 이용에 대한 중요성이 새로이 부각되고 있다.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.116-126
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• 2015

The purpose of this study is to analyze the change of programming strategies of chinese broadcasting as competitions intensify in the niche dimension. Specifically, the niche breadth which indicates the diversity of program genre and way of program production, the niche overlap which indicates the degree of competition among the channels, are investigated. The results show, as the competition has intensified, three chinese television pursued different programming strategies; CCTV1 maintained programming strategy without big change, while Hunan and Gangso pursued change of programming strategy. However the change of programming strategies of Hunan and Gangso showed different direction; Hunan has tended narrows niche breadth of program genre and the way of progrm production, while Gangso broadens niche breadth. In overall, Chinese broadcastings have found the way of co-exist pursuing different programming strategy. And the programming strategy of Gangso satellite broadcasting which broadens niche breadth has showed better performance in rating and advertising revenue.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.691-693
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• 2002

슈퍼스칼라 프로세서 구조에서 명령어 실행을 수행하는 데 사용되는 자원은 그 양에 비해 실제로 활용된 자원의 양은 적다. 본 논문에서는 낮은 자원활용도를 보이는 자원을 활용하는 방안으로 슈퍼스칼라 프로세서를 멀티쓰레드 프로세서로 확장하는데 필요한 기본 데이터를 얻기 위해서 실제로 활용되는 자원의 양을 측정하여 어느 정도의 자원을 활용할 수 있는 지와 자원이 충분히 활용되지 못하는 원인을 분석하였다. 실험을 위해 RA(Resource Analyzer)를 구현하여 SimpleScalar 시뮬레이터에서 제공되는 명령어 파이프라인 트레이스 파일을 분석하여 각 파이프라인 단계에서 처리되는 자원의 활용도를 실험하였다. 자원 활용도가 낮은 원인을 분석하기 위해 프로그램 내에 존재하는 데이터 의존성과 여러 가지 미스 요인들의 비율을 실험을 통해 알아본 결과 IPC(Instruction Per Cycle)는 평균 0.6으로 나타났으며, EX단계의 평균 활용 빈도는 22.9%로 낮아 멀티쓰레드 처리의 필요성이 있음을 확인할 수 있었다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.1
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• pp.10-18
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• 2016

RC(Reinfored Concrete) structures exposed to carbonation in urban city have durability degradation with extended service life and cracks in concrete causes a local accelerated carbonation. In the present work, crack effect on carbonation depth is investigated and the service life of RC structure is evaluated considering cracks from early age and time-dependent cracks based on the previous field investigation. DFP(Durability Failure Probability), safety index, and the related service life are calculated considering the time to crack width reaches to maximum crack width(0.3mm). The results with time effect on crack width show lower DFP and longer service life, which seems to be reasonable compared with conservative results from crack effect from initial stage. Furthermore, crack effect is evaluated to be insignificant on DFP and service life. The technique with time-dependent crack effect on carbonation can be effectively used for RC structure containing cracking in use.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.8-15
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• 2019

When RC(Reinforced Concrete) structures are exposed to harsh environment, deterioration phenomenon occurs, and the corrosion in rebar due to chloride intrusion is known as representative deterioration, so called chloride attack. In this paper, chloride resistance performance of 2 years aged concrete is evaluated considering 3 levels of water to binder ratio(0.37, 0.42, and 0.47) and 2 levels of substitution ratio of fly ash(0% and 30%). Accelerated chloride diffusion coefficient tests referred to Tang's method, total passed charge tests referred to ASTM C 1202, and compressive strength tests referred to KS F 2405 are performed. With adaptation of the previous test results and the results from this study, time-dependent chloride diffusion characteristics are analyzed for each concrete. The FA(Fly Ash) concrete has higher chloride resistance performance than OPC(Ordinary Portland Cement) concrete. According to the evaluation standard of ASTM C 1202, the FA concrete has "Moderate" grade after 49 days while OPC concrete does "Moderate" grade after 365 days. As the results of time-parameter for chloride diffusion, OPC concrete and FA concrete show the decreasing behavior of time-parameters with increasing water to binder ratio. Also, FA concrete has 1.57~2.74 times of time-parameter than OPC concrete. That's cause is thought that the time-parameter indicates the gradient of decreasing of diffusion coefficient. FA concrete has higher time-parameters than OPC concrete by pozzolanic reaction of FA.

• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.151-156
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• 2001

(1) 21세기 우리나라가 선진국에 진입하여 초일류 국가로 발돋움하기 위해서 반드시 해결해야 할 과제는 지식기반사회로의 성공적인 이행과 디지털 경제 시대에의 능동적인 대응임. (2) 지식기반사회 그리고 디지털 경제시대는 정보와 지식이 가치 창출과 경쟁력의 핵심 원천인 동시에 경제활동의 중심이 되며, 이러한 지식과 정보를 창출 획득, 활용 할 수 있도록 하기 위한 인적자원개발 관리가 국가 발전의 핵심 전략임. (3) 대다수 OECD 회원국에서는 이미 지난 세기말부터 지식기반사회로 이행하기 위한 국가 발전의 핵심 전략으로 인적자원개발 관리에 관심과 정책을 총집결하여 왔으며, 국가 차원의 교육개혁추진과 관련부처의 통폐합 등 인적자원개발 관리체제를 재구축 하였음. (4) 부존자원이 전무하여 사람에 의존할 수밖에 없는 우리나라도 다각적으로 인적자원개발 관리에 관심을 보이고, 정책을 펼쳐왔지만 아직 국가 차원의 인적자원개발 관리체제가 미흡하여 정책의 일관성이 결여되어 있을 뿐만 아니라 곳곳에 인적자원개발 관리의 비효율 비능률이 초래되고 있음.

• Korean Journal of Social Welfare Studies
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• v.42 no.1
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• pp.433-461
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• 2011

This study investigated changes and determinants of public pension generosity and pension spending in welfare states during the last retrenchment period. Path-dependency thesis, industrialization theory and power resources model were examined with the twelve welfare states from 1980 to 2007. The main results are as follows. First, the developments of benefit generosity and pension spending have been differently presented according to pension structure. Second, the cross-national pooled-time series analysis confirmed that pension structure is the most significant factors to determine the level of benefit generosity and pension spending. Third, the positive effect of population ageing on pension spendings were proved even without any changes of pension generosity. New social risks, however, have restrained the pension spending. Fourth, the power of the left party and labor union did not affect the pension policy, which implies that power resources theory cannot explain the development of pension policy in this retrenchment period.

• Resources Recycling
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• v.31 no.1
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• pp.29-36
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• 2022

The hydrogen reduction behavior of molybdenum oxides was studied using a horizontal-tube reactor. Reduction was carried out in two stages: MoO₃ → MoO₂ and MoO₂ → Mo. In the first stage, a mixed gas composed of 30 vol% H₂ and 70 vol% Ar was selected for the MoO₃ reduction because of its highly exothermic reaction. The temperature ranged from 550 to 600 ℃, and the residence time ranged from 30 to 150 min. In the second step, pure H₂ gas was used for the MoO₂ reduction, and the temperature and residence time ranges were 700-750 ℃ and 30-150 min, respectively. The hydrogen reduction behavior of molybdenum oxides was found to be somewhat different between the two stages. For the first stage, a temperature dependence of the reaction rate was observed, and the best curve fittings were obtained with a surface reaction control mechanism, despite the presence of intermediate oxides under the conditions of this study. Based on this mechanism, the activation energy and pre-exponential were calculated as 85.0 kJ/mol and 9.18 × 10⁷, respectively. In addition, the pore size within a particle increases with the temperature and residence time. In the second stage, a temperature dependence of the reaction rate was also observed; however, the surface reaction control mechanism fit only the early part, which can be ascribed to the degradation of the oxide crystals by a volume change as the MoO₂ → Mo phase transformation proceeded in the later part.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.3
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• pp.85-97
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• 2015

This study examined the effects of outside directors and CEO duality on acquisition strategies and performance of Korean firms in high-technology industry. Based on the resource dependence theory, we focused on the service and resource-dependence roles from board of directors in the process of decision-making of acquisition strategies. In addition, CEO opportunism behavior rises when CEO serves as chairperson of board and induces the negative effects on acquisition performance. Specifically, we investigated the interaction effects between outside directors ratio and CEO duality. For the period of 2004 to 2012, 246 acquisitions of Korean firms in high-technology industry were analyzed to test our intended hypotheses. Our results indicate that there exist positive relationship between outside director ratio and acquisition performance for Korean high-technology firms. Negative associations prevail between CEO duality and performance consequences of acquisitions. While outside director ratio has a positive effect on acquisition performance when there is a presence of CEO duality, negative effect prevail for outside director ratio on acquisition performance in the absence of CEO duality position to hold our interaction hypothesis. The favor of dual structure can be explained with implications referring to unity of command and strong leadership driven from CEO duality that enhances the resource dependence roles of board of directors in the context of high-technology industry acquisition behaviors rendered by Korean firms.