• Journal of the Korean Wood Science and Technology
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• 제44권2호
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• pp.231-240
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• 2016

The change in chemical compositions of leachate and medium density fiberboard (MDF) from a laboratory-scale simulated landfill which constructed in a plastic container containing alternating layers of soil and MDF was investigated to evaluate decomposing of MDF in soil. Four treatments were conducted: 1) MDF in soil, 2) MDF only, 3) cured UF resin in soil, and 4) soil only. Molecular weight (MW) distribution of compounds in leachate from soil only treatment did not change over time. In UF resin in soil treatment, the MW distribution shifted to a lower MW distribution over time, while the peak shifted to the left indicated changing to higher MW distribution in leachate from treatment 1 and 2 contained MDF. Higher percent nitrogen in leachate was observed in MDF containing treatments due to the UF resin in the MDF. The percent carbon slightly increased in MDF only while that greatly decreased in MDF in soil treatment maybe due to bacterial activity. The percent of extractable materials from the MDF decreased greatly on day 35 compare to day 0, and subsequently did not change much on day 77. In contrast, percent holocellulose and lignin did not change much over time. No structural change of the wood fiber in MDF occurs during the study. Water-soluble materials from MDF in soil contributed the change in chemical composition of leachate.

• Communications for Statistical Applications and Methods
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• 제8권2호
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• pp.543-556
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• 2001

This study suggests integrated neural network modes for he stock price index forecasting using change-point detection. The basic concept of this proposed model is to obtain significant intervals occurred by change points, identify them as change-point groups, and reflect them in stock price index forecasting. The model is composed of three phases. The first phase is to detect successive structural changes in stock price index dataset. The second phase is to forecast change-point group with various data mining classifiers. The final phase is to forecast the stock price index with backpropagation neural networks. The proposed model is applied to the stock price index forecasting. This study then examines the predictability of integrated neural network models and compares the performance of data mining classifiers.

• ETRI Journal
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• 제45권2호
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• pp.267-276
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• 2023

R&D strategies of companies with low and high technological levels are discussed based on the concept of technology convergence and divergence. However, empirically detecting enterprise technology convergence in the distribution of enterprise technology (total productivity increase) over time and identifying key change factors are challenging. This study used a novel statistical indicator that captures the internal technology distribution change with a single number to clearly measure the technology distribution peak as a change in critical bandwidth for enterprise technology convergence and presented it as evidence of each technology convergence or divergence. Furthermore, this study applied the quantitative technology convergence identification method. Technology convergence appeared from the separation of total corporate productivity distribution of 69 IT companies in Korea in 2019-2020 rather than in 2015-2016. Results indicated that when the total technological level was separated from the technology leading and technology catch-up, IT companies were found to be pursuing R&D strategies for technology catch-up.

• 한국기후변화학회지
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• 제9권2호
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• pp.181-195
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• 2018

On December 12, 2015, the Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC) adopted the Paris Agreement, in which several developed and developing countries all committed to participating in the reduction of greenhouse-gas (GHG) emissions. South Korea has submitted an intended nationally determined contribution (INDC) proposal with a target to cut down 37% greenhouse gas business as usual (BAU) until 2030 in preparation for the 2030 GHG BAU. Under the post-2020 regime, which will be launched from 2021 as the agreement entered into force early, it is expected that efforts to support GHG reduction and adaptation to climate change in developing countries will be accelerated with the utilization of technologies and financial resources of developed countries. South Korea has established the Basic Plan for Climate Change Response and the Basic National Roadmap for Greenhouse Gas Reductions by 2030 to promote the response to climate change at the government level. The Ministry of Science and ICT, as the National Designated Entity designated by the UNFCCC, has come up with middle and long-term strategies for climate technology cooperation. South-Korea has an abundance of energy-consuming industries to support its export-oriented industrial structure; it is thus expected that achieving the GHG reduction target will incur a considerable cost. Moreover, in order to meet the reduction target (11.3%) of the intended nationally determined contribution proposed by South Korea, it is necessary for South Korea to actively promote projects that can achieve GHG reduction achievements, and financial resources are needed as leverage to reduce risks that can occur in the early stages of projects and attract private sector investment. This paper summarizes the theoretical discussions on climate finance and conducted a comparative analysis on the status of the funds related to climate change response in the UK, Germany, Japan and Denmark. Through this, we proposed the legal and policy tasks that should be carried forward to raise public funds that can be used for creation of new industries related to climate change as well as to reduce GHG emissions in South Korea. The Climate Change Countermeasures Act, which has been proposed by the National Assembly of South-Korea, stipulates the establishment of funds but there is no additional funding except for general account. In this regard, it is also possible to take measures such as the introduction of carbon tax or the collection and use of royalties through technology research and development projects for climate change, such as Industrial Technology Innovation Promotion Act. In addition, since funds are used in various fields such as domestic greenhouse gas reduction, technology development, and overseas projects, it is necessary to establish a system in which various ministries cooperate with the operation of the fund.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.439-444
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• 2005

Shotcrete lining is likely to be deteriorated due to the ground water which the lining is exposed to. Some tunnel collapses seemed to be affected by shotcrete degradation were reported. But there isn't any assessment method of shotcret long-term degradation. So, Experimental technology for shotcrete long-term degradation modeling was developed in this study. The shotcrete long-term degradation modeling, developed in other study in Korea Institute of Construction Technology, require the time-history of volume change. Digital strain observation system was used to acquire the time-history of volume change. To verify the Strain Observation Digital System, the measurement using the system was compared to the one using a micrometer. Through this process, The experiment for shotcrete long-term degradation modeling was set up.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 추계학술발표대회 논문집
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• pp.139-142
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• 2005

The design of the period after 20th century has rapid change. It is due to the improvement and the change of technology which is composed of the parameter that is the science and the machine after the Industrial Revolution. The technology becomes the criteria of the value and appears to the symbol of the period. The purpose of this study is to define the expression characteristics by the development of technology and to examine how specificly it makes the influence on the change of Interior expression characteristics. Interior design can be expressed more creative and 4th dimensional spaces by the development of technology from the space, form and material side

• East Asian mathematical journal
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• 제39권4호
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• pp.437-454
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• 2023

The core of the change in the era of the 4th industrial revolution is the change in the base of 'digital technology'. These changes are incomparably large and are expected to have a more important impact on our lives than ever before. One of the major inflection points in the transition to the digital era is the education field, and IT technology has become an essential element in the educational field. Accordingly, this study examines domestic research trends related to the educational environment based on digital technology. Then, we would like to provide implications for the establishment of a digital-based educational environment that will change in the future. To this end, Semantic network analysis has been conducted to quantitatively structure text data obtained from studies related to digital technology in the field of mathematics education over the past 10 years, and the discussion will continue based on the results.

• 통상정보연구
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• 제16권5호
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• pp.203-221
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• 2014

본 연구는 본사와 해외자회사간 협력에 대해 기술변화 및 경쟁강도와 같은 외부환경요인들의 영향을 검증하였다. 연구프레임워크의 타당성에 관해 한국기업의 샘플을 통하여 실증적으로 테스트하였다. 검증결과는 외부환경요인의 불확실성이 증가할수록 조직적 조정으로서 본사와 자회사간 협력수준이 큰 것으로 나왔다. 즉, 연구결과에서 기술변화와 본사-자회사간 협력 간에 유의적인 상관관계가 있음을 보여주고 있다. 기술변화는 본사와 자회사간 협력에 대해 긍정적인 영향을 미치는 것으로 나타났다. 또한 실증적결과는 경쟁강도가 본사와 자회사간 협력에 대해서도 직접적인 영향을 주고 있음을 보여 주었다.

• 정보저장시스템학회:학술대회논문집
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• 정보저장시스템학회 2005년도 추계학술대회 논문집
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• pp.185-189
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• 2005

We reported here nano-scale electrical phase-change recording in amorphous $Ge_2Sb_2Te_5$ media using an atomic force microscope (AFM) having conducting probes. In recording process, a pulse voltage is applied to the conductive probe that touches the media surface to change locally the electrical resistivity of a film. However, in contact operation, tip/media wear and contamination could major obstacles, which degraded SNR, reproducibility, and lifetime. In order to overcome tip/media wear and contamination in contact mode operation, we adopted the W incorporated diamond-like carbon (W-DLC) films as a protective layer. Optimized mutilayer media were prepared by a hybrid deposition system of PECVD and RF magnetron sputtering. When suitable electrical pulses were applied to media through the conducting probe, it was observed that data bits as small as 25 nm in diameter have been written and read with good reproducibility, which corresponds to a data density of $1 Tbit/inch^2$. We concluded that stable electrical phase-change recording was possible mainly due to W-DLC layer, which played a role not only capping layer but also resistive layer.

• 공학교육연구
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• 제22권3호
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• pp.11-17
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• 2019

With technology rapidly changing our economic, cultural and social realities, the question of how to educate the generation for the fourth industrial revolution has been a pressing issue. The purpose of this study is to review teachers' perception regarding the educational change in the fourth industrial revolution. For this purpose, we surveyed 420 school teachers and administrators. Most teachers highly understand The Fourth Industrial Revolution and they think AI(Artificial Intelligence) is a core technology. They recognize The Fourth Industrial Revolution is very important and great influence in the education field. For this, they need educational innovation in the education field. Elementary school teacher perceive understanding Elementary school teachers think that understand The Fourth Industrial Revolution and change of curriculum is highly important. And, Secondary school teachers perceive that the change of education system and class is very necessary. Lastly, STEAM education is the most appropriate to prepare for a changing society.