• Korean System Dynamics Review
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• v.9 no.1
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• pp.171-197
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• 2008

By applying Systems Simulation technique, this paper aims to investigates the dynamics underlying the coevolution of IT(information technology) and the society. Particularly, a series of basic questions are explored to answer by developing a simulation model for the mechanisms underlying the 'hype curve' ever occurring in the course of technology diffusion into society: First, why hype curve appears in the process of technology and society coevolution. Second, how to enhance the tapering level at the final stage of coevolution. Third, what are the key policy leverages and when is the right time for the policy intervention. As now, inflated expectations regarding ubiquitous information technology (u-IT) are growing very fast and higher than those for the previous technologies, which would result in overshoot followed by collapse of visibility and thus incur tremendous amount of social costs. In this regard implications drawn from this study perhaps give some insights not necessarily to the academics but also to the practitioners and policy makers facing the advent of u-IT as a new emerging horizon of information society.

• Environmental and Resource Economics Review
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• v.16 no.2
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• pp.275-311
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• 2007

Hydrogen energy is emphasized as a substitutable energy of carbon-based energy system in the future, since it is non-depletable and clean energy. Long term vision of Korean government on the national energy system is to promote hydrogen energy by 15% of final energy demand until 2040. This study analyzes economic impacts of hydrogen energy development employing a dynamic CGE model for Korea. Frontier technology such as hydrogen energy is featured as slow diffusion at the initial stage due to the learning effect and energy complementarity. Without government intervention, hydrogen energy would be produced upto 6.5% of final energy demand until 2040. However, if government subsidizes sales price of hydrogen energy by 10%, 20%, and 30%, share of hydrogen energy would increase 9.2%, 15.2%, and 37.7% of final energy demand. This result shows that the slow diffusion problem of hydrogen energy as frontier technology could be figured out by market incentive policy. On the other hand, production levels of transportation sector would increase while growth rate of oil and electricity sectors would decline. Household consumption would be affected negatively since increase of consumption due to the price decrease would be overwhelmed by income reduction owing to the increase of tax. Overall, GDP would not decrease or increase significantly since total production, investment, and export would increase even if household consumption declines.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.123-131
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• 2005

This study was focused on adsorption, leaching, photolysis, and hydrolysis of the fungicide procymidone in soils. Adsorption type of procymidone on three different soil were well fitted to Linear and Freundlich isotherm. Distribution coefficients (Kd) were ranged from 2.75 to 12.18 and Freundlich isotherm Kf value $1.99{\sim}9.98$, 1/n value $0.74{\sim}0.89$. Desorption rates were $20.1{\sim}34.0%$ (Namgye), $26.3{\sim}44.6%$ (Jigog) and $31.6{\sim}50.9%$ (Baegsan series) and desorption hysteresis were $0.65{\sim}0.79,\;0.55{\sim}0.73\;and\;0.49{\sim}0.68$. Procymidone seemed to be stable to photolysis in acidic and neutral solutions but hydrolyzed rapidly in alkaline solution. Considering leaching properties procymidone mobility low in soils.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.28-39
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• 2016

Since 2002, Korea Government has introduced Green Standard for Energy and Environmental Design Certification for reducing GHG emission in building area. However, total number of G-SEED Certification is only around 1% of total number of approved apartment buildings despite the various boosting policies. In this situation, most boosting policies and policy improvement researches are leaning toward the supplier's aspect. However, comprehensive relation and dynamics between consumer and supplier has to be considered because housing market is operated by market participants' mutual interaction. Therefore, this research presents system dynamics models based on decision making analysis of consumer and supplier in G-SEED Certification apartment building market. Then, this research evaluate the validity of boosting policies using the model. The proposed analysis can assist government to make next G-SEED Certification boosting policy.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.259-273
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• 2022

Interactions between species in a community are very complex, and they are visualized and analyzed through a food web in simple way. Food web is a network of species connected by trophic links showing energy flow from prey to predator. Various models were developed to characterize the food web in ecosystems. In this study, we classified food web models to static models such as Ecopath and dynamic models such as AQUATOX. We presented characteristics of several different types of food web models in each category, and reviewed their applications used in aquatic ecosystems. Finally, we presented issues to be considered to develop food web models.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.105-111
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• 1997

Root dynamics of a pine stand at Hongcheon, Korea was assayed with two kinds of soil samplers which had been tentatively manufactured to renovate the routine soil sampler, Oakfield soil sampler. Root-mixed soil samples were collected on December of 1995, March, May, August and December of 1996 within each randomly selected 8 plots. The amount of roots collected by the two kinds of soil samplers were not significantly different at the 5% level, which indicated that the renovated sampler was more desirable to be used since the sampler showed efficiencies in time for collection and quantification than the routine sampler. The quantities of total root in 100g soils were 469mg on December of 1995, and 352mg, 473mg, 461mg, 522mg on the following March, May, August and December, respectively. That is, total amount of roots showed the smallest in Spring and reached maximum in early Winter, although the differences were not significant among each season. By the way, the alive roots and dead roots showed significant differences among season, the alive roots took about 90% from May to early December while they decreased down to some 65% from late December to March. The roots of Pinus densiflora S. et Z. took about 46% of total roots although the species comprised 70% of crown layer, and the ratio of fine-roots of the species were higher than that of other species. By the way, the dynamics of total roots and that of alive roots were quite different. Thus, the study for root dynamics such as fine roots which take a major role for mycorrhizae formation or nutrient uptake should not be inferred from the data of total root dynamics but be investigated in detail by dividing them into each class.

• Korean Journal of Ecology and Environment
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• v.56 no.2
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• pp.172-186
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• 2023

Small ponds, which exhibit unstable succession pattern of plankton community, are less well studied than large lakes. Recently, the importance of small ponds for local biodiversity conservation has highlighted the necessity of understanding the dynamics of biological community. In the present study, we collected zooplankton from three small reservoirs with monthly basis and analyzed their seasonal dynamics. To understand the complicated zooplankton community dynamics of small reservoirs, we categorized zooplankton species into four groups (LALF Group, Low Abundance Low Frequency; LAHF Group, Low Abundance High Frequency; HALF Group, High Abundance Low Frequency; HAHF Group, High Abundance High Frequency) based on their occurrence pattern (abundance and frequency). We compared the seasonal pattern of each group, and estimated community diversity based on temporal beta diversity contribution of each group. The result revealed that there is a relationship between groups with the same abundance but different occurrence frequencies, and copepod nauplii are common important component for both abundance and frequency. On the other hand, species included with LALF Group throughout the study period are key in terms of monthly succession and diversity. LALF Group includes Anuraeopsis fissa, Hexarthra mira and Lecane luna. However, groups containing species that only occur at certain times of the year and dominate the waterbody, HALF Group, hindered to temporal diversity. The results of this study suggest that the species-specific occurrence pattern is one key trait of species determining its contribution to total annual biodiversity of given community.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.334-334
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• 1994

Omeprazole의 약동학적 Parameter는 tmax를 제외하고 두 군간에 유의한 (p<0.001) 차이론 보였다 : AUC의 평균치는 5-mephenytoin hydroxylation poor metabol izer에서 extensive metabol izer에 비해 약 6-7배 컸다. Omeprazole sulfone의 parameter는 omeprazole에서 관찰된 두 군간의 차이와 유사하였다. 그러나 5-hydroxyomeprazole의 경우에는 Cmax, AUC 등이 extensive metabolizer에서 더컸다. Omeprazole의 청소율은 S-mephenytoin hydroxylation 대사능(MR)과 유의한 상잔관계(rs=0.79, p<0.01)를 보였으며, omeprazole과 그 대사물(5-hydroxyomeprazole 및 omeprazole sulfone)의 반감기 또한 S-mephenytoin hydroxylation 대사능과 유의한 상관성을 보였다.

• KOREAN POULTRY JOURNAL
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• v.41 no.7
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• pp.98-101
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• 2009

경영분석이란 기업이나 농장의 대차대조표와 손익계산서를 바탕으로 재무상태와 경영성적의 정도를 판단하는 기술(기법)이다. 최초의 경영분석은 은행가들이 돈을 빌려간 사람의 신용상태 또는 상환능력을 파악하기 위하여 시작하였지만 오늘날에는 재무분석 뿐만 아니라 제품, 영업, 판매, 조직, 업무, 지원 모든 분야에서 경영분석이 이루어지고 있다. 대차대조표 등 재무제표를 자료로 하여 자산구성, 자본구성, 자산과 자본의 상호관계를 분석하여 경영에 투하된 자본이 어떻게 운용되는가, 그 자본의 원천은 어디에서 얻게 되었는가를 규명하는 분석이 있다. 경영분석은 다시 두 가지로 구분되는 바, 시간을 정해두고 대차대조표를 자료로 하여 일정한 시점에서의 각종 지표를 비교하는 정태(靜態)분석과 손익계산서 등을 자료로 하여 일정 기간 동안의 수익성을 파악하는 것을 동태(動態)분석이 그것이다.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.106-110
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• 1998

최근 용융방사섬유의 제조에 이용되고 있는 고속방사법은 높은 신장속도하에서 일어나는 배향결정화에 의한 섬유구조형성을 목적으로 하는 방사법으로, 방사선에서의 동력학은 폴리머의 열특성, 냉각거동 및 방사선상에서 작용하는 응력 등의 많은 인자에 의해 영향을 받는다. 복합섬유란 특수한 복합방사장치를 이용하여 두 개의 폴리머가 동시에 압출되어 하나의 필라멘트를 형성하도록 방사한 섬유로써 권축섬유, 열융착형섬유, 이형단면섬유, 전도성섬유, 초극세섬유 등 특수한 섬유의 제조에 이용되기 때문에 그 상업적 관심도가 크다[1].(중략)