• 노동경제논집
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• 제28권3호
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• pp.141-166
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• 2005

본 연구는 청년층의 학력과잉이 경제위기로 어떻게 전개되었으며 또한 이로 인한 교육투자 수익률이 어떻게 변하였는가를 살펴보았다. 이를 위해 본 연구는 경제위기 전인 1996년도 임금자료와 2000년도 임금자료 각각을 직업사전과 비교함으로서 1996년도의 과잉학력률과 2000년도의 과잉학력률을 인적 속성 및 근로자가 종사하는 산업 직종 그리고 사업체 규모 등 다각적으로 살펴보았다. 그리고 경제위기가 과잉학력에 어떻게 영향을 미쳤는지를 희귀분석했다. 그 결과 경제위기 이후 과잉학력이 보다 심화되었음을 알 수 있었다. 그 후 이러한 변화가 교육 투자수익률에 어떤 영향을 미쳤는지를 살피기 위해 각년도 과잉학력자의 시간당 임금과 적정학력자의 임금을 비교하였으며 또한 경제위기가 투자 수익률에 미친 영향을 살피기 위해 회귀분석을 하였다. 그 결과 학력과잉자의 시간당 임금이 적정학력자의 임금보다 여전히 높았으나 경제위기를 겪으면서 그 임금 차의 폭은 상당히 줄어들었음을 알 수 있다. 그러한 추세가 일시적인 것이 아니라 고착화되고 있는지를 살피기 위해 2002년도 자료로도 분석해 본 결과도 마찬가지로 나타났다.

• 한국수자원학회논문집
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• 제42권1호
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• pp.33-50
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• 2009

본 연구에서는 SLURP 장기 수문모형을 이용하여 미래기후와 예측된 토지이용자료 및 식생의 활력도를 고려한 상태에서 하천유역의 수문요소에 미치는 영향을 분석하였다. 경안천 상류유역($260.4\;km^2$)을 대상유역으로 선정하여 4개년(1999-2002) 동안의 일별 유출량 자료를 바탕으로 모형의 보정(1999-2000)과 검증(2001-2002)을 실시하였다. 모형의 보정 및 검정 결과 Nash-Sutcliffe 모형효율은 0.79에서 0.60의 범위로 $R^2$는 0.77에서 0.60의 범위로 나타났다. 미래 기후자료는 IPCC(Intergovernmental Panel on Climate Change)에서 제공하는 A2, A1B, B1 기후변화시나리오 의 MIROC3.2 hires, ECHAM5-OM 모델의 결과 값을 이용하였다. 먼저 과거 30년 기후자료(1977-2006, baseline)를 바탕으로 각 모델별 20C3M(20th Century Climate Coupled Model)의 모의 결과 값을 이용하여 강수와 온도를 보정 한 뒤 Change Factor Method로 downscaling 하였다. 미래 기후자료는 2020s(2010-2039), 2050s(2040-2069), 2080s(2070-2099)의 세 기간으로 나누어 분석하였다. 불확실성을 줄이고자 개선된 CA-Markov기법으로 미래 토지이용을 예측하였으며, 월별 NDVI와 월평균기온간의 선형 회귀식을 도출하여 미래의 식생지수 정보를 추정하였다. 모형의 적용결과, 미래 유출량은 MIROC3.2 hires는 A1B(2080s) 시나리오에서 연 유출량이 21.4% 증가, ECHAM5-OM은 A1B(2050s) 시나리오에서 8.9% 증가하였다. 증발산량은 MIROC3.2 hires가 3%, ECHAM5-OM은 16% 증가하였다. 미래 토양수분량은 현재에 비해 약 1% 정도 증가하였다.

• 한국수자원학회논문집
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• 제46권12호
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• pp.1235-1247
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• 2013

본 연구에서는 충주댐($2750{\times}10^6m^3$) 및 조정지댐($30{\times}10^6m^3$)을 포함한 유역을 대상으로 미래 기후변화가 댐 저수량에 미치는 영향을 분석하기 위해 SWAT(Soil and Water Assessment Tool) 모형을 활용하였다. 3지점의 9개년(2002~2010)동안의 자료를 이용하여 검보정을 실시한 결과 유출량에 대해서는 Nash-Sutcliffe 모델 효율(NSE)이 0.73으로, 두 댐의 저수위에 대해서는 0.86으로 나타났다. 미래 기후변화 시나리오자료는 IPCC(Intergovernmental Panel on Climate Change)에서 제공하는 GCMs (General Circulation Models) 중 HadCM3 모델의 SRES(Special Report on Emission Scenarios)에 의한 B1과 A2 시나리오를 구축하였다. 미래 월별 기온과 강수자료는 과거 30개년(1977~2006, baseline period) 자료는 편의보정(bias-correction) 기법을 이용하여 오차보정 후, Change Factor (CF) method를 이용하여 상세화 하였다. 미래 연평균 기온은 2040s (2031~2050)에 $0.9^{\circ}C$, 2080s (2071~2099)에는 $4.0^{\circ}C$까지 증가할 것으로 예측되었고, 연평균 강수량은 2040s에 9.6%, 2080s에 20.7% 증가하는 것으로 나타났다. 과거 대비 미래 증발산량은 15.3%까지 증가하고, 토양수분은 최대 2.8% 감소하였다. 과거 9개년 평균 댐 방류스케줄에 따른 미래 댐 연평균 유입량은 가을철을 제외한 대부분 기간에 최대 21.1%까지 증가하는 경향을 보였다. 미래 가을철 댐 유입의 감소로 인해 현재 방류 패턴으로는 연말까지 결국 저수량을 회복하지 못하는 것으로 나타났다. 미래 풍수년과 갈수년에는 댐 저수량의 시간적 변동이 더욱 불안정해지므로 각각 저수량의 상향 및 하향 조정에 주의를 기울여야 한다. 따라서 기후변화 적응을 위한 댐 방류 패턴 조절이 필요하다고 판단된다.

• Journal of Mechanical Science and Technology
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• 제16권11호
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• pp.1412-1419
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• 2002

Dynamic shear tests for the tough-pitch copper at high strain and high strain rate was performed. The Split Hopkinson Pressure Bar (SHPB) compression test system was modified to yield a shear deformation in the specimen. Hat-shaped specimens for the tough-pitch copper were adopted to generate high strain of γ=3～4 and high strain-rate of γ= 10$^4$/s. The dynamic analysis by ABAQUS 5.5/EXPLICIT code verified that shear zone can be localized in hat-shaped specimens. A proper impact velocity and the axial length of the shear localization region wert determined through the elastic wave analysis. The displacement in a hat-shaped specimen is limited by a spacer ring which was installed between the specimen and the incident bar. The shear bands were obtained by measuring the direction of shear deformation and the width of deformed grain in the shear zone. The decrease of specimen length has been measured on the optical displacement transducer. Dynamic shear stress-strain relations in the tough-pitch copper were obtained at two strain-rates.

• Management Science and Financial Engineering
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• 제8권1호
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• pp.21-38
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• 2002

Rapid advances in information technology(IT) and telecommunication systems impact the number and quality of decision-making in organizations. Specifically, middle mangers must posses or develop the creativity necessary for survival in a constantly changing and volatile business environment. While tradition and conventional wisdom tell us that a middle managers role centers on control and monitoring, todays competitive arena has spun out a new managerial requirement developing and maintaining an innovative attitude. Problematically, most previous research has focused on the issue of changing decision authority (i. e. centralization/decentralization). Moreover, much previous research has also largely ignored environmental changes exposing new roles that middle managers have assumed. This study explores the means of identifying middle managerial roles, managerial possibilities involving the growing popularity of open systems through electronic brainstorming, and an adaptation and development of Diffusion Theory and attempt to counter criticism leveled at the theory's inability to provide an adequate explanation for diffusion of complex organizational technology. This paper develops three ideas: 1) Introducing the 'Chasing Curve' as a theoretical background. 2) Suggesting a new methodology using electronic brainstorming for analyzing the gap between Knowing (the perceived importance of middle managers' roles) and Doing (the degree of current status of middle managers' roles), which we term the 'Spiral Gap Analysis Model'. 3) Identifying a feedback system for minimizing the Knowing - Doing gap, aimed at development of IT strategic priority decision support, which we call this the 'Star Process'.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.165-166
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• 2002

Hydrogen free diamond like carbon (DLC) films were prepared on steel substrates by using a single ion beam in a configuration that allowed sputtering of a graphite target and at the same time allowed to impact the substrate at a grazing angle. The DLC films so prepared have improved properties with increased disorder and with modest hardness that is slightly higher than previously reported values. We have studied the effects of $N_2^+$ ions implantation on such films. It is found that the implantations of nitrogen ions into DLC films lead to chemical modifications that allowed N atoms to be incorporated into the carbon network to produce a nitrogenated DLC. Nano-indentation experiments indicated that the nitrogenated films have consistently higher hardnesses ranging from 30 to 45GPa, which represents a considerable increase in surface hardness, compared with non-nitrogenated precursor films. The investigations by XPS and Raman spectroscopy suggests that the $N_2^+$ implanted DLCs had undergone both chemical and structural modifications through the incorporation of N atoms and the increased ratio of $sp^3/sp^2$ type bonding. The observed high hardness was therefore attributable to these structural and chemical modifications. This result has implication for the preparation of super hard wear resistant films required for tribological functions in devices.

• KIEAE Journal
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• 제8권5호
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• pp.69-76
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• 2008

Recent industrial development and technological breakthroughs have made our life much more convenient, however, at the cost of environmental degradation resulting from indiscreet focus on development in combination of disregard of impact on eco system. Notably, global warming is one of the most serious environmental issues, triggering attention for environmental protection in Korea and elsewhere. To address such issues, nations around the world are beefing up environmental regulatory framework such as UNFCCC(United Nations Framework Convention on Climate Change) to tackle environmental challenges from global perspective. Against the backdrop, Korea has been engaging actively in global initiatives to reduce climate change, ratifying UNFCCC in 1993 and the Kyoto Protocol in October, 2002. However, unlike the government responding to environmental degradation in earnest, construction industry is far from making efforts to reduce wastes. Construction waste is a source of environmental deterioration world wide and adds to the aggregate cost that construction companies should assume. Korean construction firms also need to develop initiative aggressively to respond to changes in environmental policies and reduce construction costs. Therefore, this study aims at examining sources of wastes in construction sites and suggest solution in order to prod local construction companies to develop countermeasures.

• Asian-Australasian Journal of Animal Sciences
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• 제24권11호
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• pp.1629-1636
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• 2011

Global pork markets are becoming more competitive, riding the wind of the bilateral free trade agreement. China is the world's largest pork producer with nearly 50% of the world's total production. China's fast growing economy has provided its people with higher purchasing power, resulting in a rapid expansion of the Chinese swine industry over the past decades. Worldwide, China consumes the greatest amount of pork and it is believed that this trend will continue. Japan is the world's largest pork importing country, even though it also produces a lot of pork. The Japanese swine industry encounters weighty obstacles in production costs and environmental limitations which result in reduced domestic supply and creates the situation in which Japan has to import a significant amount of pork for their consumption. South Korea is also a large buyer of pork, with a status greatly influenced by the struggle that the country has faced with Foot and Mouth Disease (FMD) which occurred in 2000, 2002 and 2010. High production costs, low production efficiency, and forced culling following the FMD outbreak resulted in the loss of many hog farming households in the country, reducing supply of domestic pork in the face of continued demand. Overall, pork production in these economically important countries can greatly impact the industry globally. The goal of this review paper is to describe pork production in China, Japan, and South Korea and discuss these countries' role in global pork export markets.

• 간호행정학회지
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• 제8권4호
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• pp.575-583
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• 2002

Purpose : The purpose of this study was examine the effects of Self-Development training on the Self-Identity for head nurses. Methods : The sample consisted of 24 head nurses in one university hospital in Seoul. The subjects were divided into two groups for the training. Self-Development training was developed by the researcher for during 4 sessions in two weeks that is, 2 hours a day/ 2 times a weeks / two weeks / each group. Self-Development training program consists of identification of self-development elements, self-identification I, self-identification II, and human relationship. Two-weeks before and 4-weeks after the training, subjects completed the questionnaires. Analysis was done by SPSS PC 10.0 for percentile, mean, standard deviation, paired t-test and correlation. Results : The results of this study showed that the Self-Identity had not significant differences before and after Self-Development Training. When compared 5 subscales, self-assertiveness is significant difference, and goal-directedness has the lowest score before and after training. 11(46%) of head nurses mean scores at the 4 weeks after training were slight higher. Conclusion: On the basis of the finding, the researcher makes the following conclusion. This study is one step towards understanding the impact of Self-Identity for the head nurses. It would be beneficial to replicate this study with larger, more diverse samples.

• 대한간호학회지
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• 제33권5호
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• pp.562-569
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• 2003

Purpose: The purpose of this longitudinal prospective study was to assess changes in fatigue and quality of life for a 6-week course of radiotherapy. Method: A descriptive and longitudinal design was used to this study. Twenty-three subjects receiving radiotherapy from a radiotherapy clinic of a general hospital completed the questionnaires. Fatigue was measured using Lee's scale(1999) and quality of life using Yang's scale(2002) weekly for 6 weeks. Result: Fatigue significantly increased(F=6.043, p=.000), and quality of life significantly decreased (F=3.938, p=.003) and physical symptoms also significantly increased(F=2.432, p=.039) during a 6-week radiotherapy. Multiple regression analysis revealed that fatigue at the first week and physical symptoms at the 6th week were the significant affecting variables(60.1% of the variance) on fatigue. And 63.2% of the variance in quality of life was explained by quality of life and fatigue at the first week and body weight change for 6 weeks radiotherapy. Conclusion: Based on these results, the fatigue and quality of life at the beginning time of radiotherapy have a lasting impact throughout the course of treatment. It suggests that nurses provide patients with information about the occurrence of fatigue during radiotherapy and the practical methods of intervening physical symptoms.