• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.686-686
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• 2009

가스하이드레이트는 수소결합을 하는 물분자의 고체상 격자(Lattice)내에 포집되어 들어가는 기체분자로 구성된 결정화합물로서 외형적인 형태는 얼음과 거의 유사하다. 천연가스 하이드레이트 기술의 최대장점으로는 액화천연가스(LNG)는 초저온인 $-162^{\circ}C$의 저장조건이 필요하지만 천연가스하이드레이트(NGH)기술은 비교적 온화한 조건인 $-15^{\circ}C$에서 천연가스를 고체상태로 저장/이용할 수 있다는 것이다. 천연가스를 $-162^{\circ}C$에서 액화시킨 LNG상태로 생산, 수송, 저장하는 경우보다 고체상태인 NGH(Natural Gas Hydrate)로 만들어서 생산, 수송, 저장할 경우 천연가스의 생산, 수송, 저장, 재가스화 등의 일련의 공정과 비교해볼 때 LNG방법보다 약 24%이상의 경비를 절감을 할 수 있다고 보고되어지고 있다. 따라서, 천연가스의 수송 및 저장기술에서의 탁월한 경제성으로 인해 선진국에서는 가스하이드레이트에 대한 활발한 연구가 진행되고 있다. 특히 일본은 5Ton/Day용량의 NGH 생산플랜트를 건설하여 시운전 중에 있다. NGH기술의 주요 활용분야는 대용량의 가스매장량을 요구하여 LNG공정기술을 적용할 수 없는 중소형가스전 또는 한계가스전에 경제적으로 적용하는 해양수송분야와 천연가스 공급망이 갖춰져 있지 못한 지역에 NGH Pellet형태로 수송/재기화하여 활용하는 내륙운송이 분야가 있다. 국내에서는 지식경제부 국책과제인 ETI(Energy Technology Innovation)사업을 시작으로 국가경쟁력 제고 차원에서 이러한 기술의 기반구촉 및 실증화 사업이 진행되고 있다. 주요 내용으로는 NGH Process Flow, Overall NGH Process concept diagram, NGH Carrier outline, NGH Land Transportation chain 등이 포함되어 있다.

• 대한불안의학회지
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• 제10권2호
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• pp.103-107
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• 2014

Objective : The objective of this study was to examine the association between childhood adversity and parenting attitude and neuroticism in adulthood. Methods : Forty nine women were recruited from community and completed Early Trauma Inventory-Short Form (ETI-SF). We compared scores on the Maternal Behavior Research Instrument (MBRI), Neuroticism of NEO Personality Inventory (NEO-PI), and Beck Depression Inventory (BDI) between women with and without childhood adversity. Results : Compared to women without childhood adversity, women with childhood adversity showed more rejecting parenting attitude and higher Depression and Self-Consciousness scores on Neuroticism domain of NEO-PI. Total ETI-SF scores and emotional abuse scores were positively correlated with rejecting attitude scores on the MBRI and BDI scores. Physical abuse scores were positively correlated with rejecting attitude scores. There were positive correlations between rejecting attitude scores on the MBRI, Neuroticism scores on the NEO-PI, and BDI scores. Conclusion : Our results suggest that childhood adversity may have a negative impact on parenting attitude and emotional state in adulthood. For girls who experienced traumatic event, early intervention is needed to prevent the development of neurotic temperament and rejecting parenting in adulthood.

• 한국토양비료학회지
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• 제46권4호
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• pp.231-236
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• 2013

This study was conducted to investigate the yield response of soybean to drought stress in 1984 and 1986 at the experiment field of the National Academy of Agricultural Science using experiment plots with different soil water tension and fertilizer levels. The average yield response factor (YRF) of soybean to evapotranspiration (ET) calculated as [(Ya/Ym)/(ETa/ETm)], where Ya, average yield; Ym, maximum yield; ETa, average ET; and ETm, maximum ET, was 0.91 with the range from 0.74 to 1.16. Relationship between yield index (YI=[Ya/Ym]) and evapotranspiration index (ETI=[ETa/PET]) was $YI=0.87{\cdot}(ETI)+0.09$. Relationship between YI and the maximum soil water tension (Hmax) was $YI=1.23-0.23{\cdot}{\log}$ (Hmax). Relationship between YI and the days of drought stressed (Dr) was $YI=0.877{\cdot}{\exp}$ ($-0.01{\cdot}Dr$). The relation between YI and fertilizer level (F) was $YI=-0.21{\cdot}F2+0.36{\cdot}F+0.33$, under very serious drought condition as the maximum soil water tension was 0.3 MPa.

• Educational Technology International
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• 제18권2호
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• pp.215-247
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• 2017

This study aims to conduct a literature review on visual scaffolding. Visual scaffolding, as a support for learning, employs various forms of visual objects which can be either content-independent or content-dependent and the types of which would be abstract-verbal, concrete-verbal, concrete-visual, or abstract visual. The effectiveness of visual scaffolding can be argued in the following three aspects: 1) explicit representation of information and emphasis of critical features in effective and efficient manner, 2) supplement of additional information, 3) structural understanding with decrease in cognitive load. The limitations of the study and the suggestions for future study are discussed.

• Educational Technology International
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• 제12권2호
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• pp.95-116
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• 2011

This study examines effects of Facebook on language learning in terms of facilitating interaction and collaboration by applying Facebook in a Korean language class. Forty one exchange students from seventeen countries who participated in the study used Facebook to exchange information and complete group projects. Results show that Facebook was effective in sharing class materials, engaging in class community and collaborating to complete assignments. Students also comment that socializing with peers was helpful, yet more activities and discussion to draw active participation is needed. This study also points out the important role of instructors who implement social media and manage the class.

• Educational Technology International
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• 제8권1호
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• pp.41-56
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• 2007

This study used the performance technology model of Robinson and Robinson to diagnose and solve the problems of the "N" organization. The performance relationship map of the "N" organization was constructed based on the results of the benchmarking, surveys, interviews, and participatory observations. According to the results of analysis, the research team suggested several interventions in three areas: textbooks, educational methods, and educational environments. The study concluded that performance technology is a very effective way to see performance problems from a holistic viewpoint and solve the problems scientifically based on this case study.

• Educational Technology International
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• 제6권1호
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• pp.121-137
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• 2005

In today's information-rich society, the need for information literacy has urgency. Three tasks of information processing are filtering, meaning-matching, meaning-construction that could be strengthened through inquiry-based learning. The cycles of reflection and practice develop the habit of mind, or conscious information processing that allow the learners to acquire higher level of information literacy. An on-line inquiry-based learning environment designed for information literacy may help learners to perform their lifelong learning better with the ability to appreciate, locate, evaluate, and use information effectively.

• Educational Technology International
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• 제6권2호
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• pp.1-9
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• 2005

Starting with analyzing the development of cyber-education in China, this article discusses experiences and lessons acquired through making reflections on the following aspects: technology vs. pedagogy, the degree education vs. non-degree education, resource exclusivism vs. resource inclusivism, mono-service system vs. multi-service system, and educational quality vs. economic profit. Finally, the paper puts forward some suggestions on the future development of cyber-education in China.

• Educational Technology International
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• 제6권2호
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• pp.131-151
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• 2005

As student-centered learning grows, formative peer assessment practices have been universally used in various fields. According to the review of traditional peer assessment practices, the formative peer assessment has five common stages: planning, assessing (giving feedback), receiving feedback, reflection, and revising. As the each stage of traditional formative peer assessment has some weaknesses, the study discusses solutions that are recommended for dealing with the problems by introducing the potential benefits of web-based peer assessment. Then, desirable future trends of web-based peer assessment are suggested. The author hopes that understanding the potential benefits of web-based formative peer assessment will promote the proper use of peer assessment and render positive effect on student learning.

• Educational Technology International
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• 제9권1호
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• pp.25-47
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• 2008

The purpose of this study is to investigate online school students' understanding of going to online school and their recognitions of the differences between online schools and brick and mortar schools/homeschool. A qualitative research was conducted with an 8^th grade teacher and sixteen 8^th grade students at an American online school. The findings of this study can be an important first step toward an in-depth understanding of online school learning environments.