• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.991-996
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• 2001

The long-term durability characteristics of high-early-strength concrete were assessed. The effect of long-term durability characteristics of high-early-strength concrete were investigated. In experiment, two different types of fiber were adopted for improvement of durability. High-early-strength fiber reinforced concretes using regulated-set cements are compared with high-early-strength concrete without fiber. The durability performance of the laboratory-cured high-early-strength concrete specimens was determined by conducting an accelerated chloride permeability, abrasion resistance, freeze-thaw, surface deicer salt scaling and wet-dry repetition test. The results indicated that incorporation of fibers enhance durability performance.

• 아태비즈니스연구
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• 제13권1호
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• pp.167-183
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• 2022

Purpose - The purpose of this study is to show the need to use the past long-term returns for investment decisions in U.S. equity funds and to suggest an investment strategy using long-term returns. Design/methodology/approach - This study solves the problem of high return volatility in long-term returns and proposes new investment portfolios based on the behavior of fund investors according to past returns. For the investment portfolio of this study, 60 months are divided into several periods and the average of the performance ranks for each period is used. Findings - First, funds with high average returns over multiple periods have lower future outflows and higher future returns than funds with high 60-month cumulative returns. Second, funds with low average returns over multiple periods have lower future inflows and lower future returns than funds with low 60-month cumulative returns. The findings mean that when making decisions based on past long-term returns, it is a smarter investment choice to buy funds with high average returns over multiple periods and sell funds with low average returns over multiple periods. Research implications or Originality - This study shows that it is necessary to use long-term returns in fund investment by analyzing the characteristics of the portfolio based on past returns. In addition, the study is meaningful in that it suggests a way to use long-term returns more efficiently based on the behavior of fund investors and shows that such investments lead to higher returns in the future.

• 경영과학
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• 제24권1호
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• pp.45-62
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• 2007

We aim to explain the role of corporate's 'long-term orientation' and 'asset specificity' in the process of SCM(Supply Chain Management) practices' effect on SCM performances, with empirical study about 167 manufacturing companies ail over the country. With confirmatory factor analysis and structural equation model using AMOS program, we conclude long-term orientation and asset specificity act as 'infra-structural role', rather than 'Intermediate role', in the process of SCM practice's effect on SCM performances.

• ETRI Journal
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• 제43권2호
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• pp.288-298
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• 2021

Abstractive text summarization is a process of making a summary of a given text by paraphrasing the facts of the text while keeping the meaning intact. The manmade summary generation process is laborious and time-consuming. We present here a summary generation model that is based on multilayered attentional peephole convolutional long short-term memory (MAPCoL; LSTM) in order to extract abstractive summaries of large text in an automated manner. We added the concept of attention in a peephole convolutional LSTM to improve the overall quality of a summary by giving weights to important parts of the source text during training. We evaluated the performance with regard to semantic coherence of our MAPCoL model over a popular dataset named CNN/Daily Mail, and found that MAPCoL outperformed other traditional LSTM-based models. We found improvements in the performance of MAPCoL in different internal settings when compared to state-of-the-art models of abstractive text summarization.

• The Plant Pathology Journal
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• 제38권4호
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• pp.395-402
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• 2022

To predict rice blast, many machine learning methods have been proposed. As the quality and quantity of input data are essential for machine learning techniques, this study develops three artificial neural network (ANN)-based rice blast prediction models by combining two ANN models, the feed-forward neural network (FFNN) and long short-term memory, with diverse input datasets, and compares their performance. The Blast_Weathe long short-term memory r_FFNN model had the highest recall score (66.3%) for rice blast prediction. This model requires two types of input data: blast occurrence data for the last 3 years and weather data (daily maximum temperature, relative humidity, and precipitation) between January and July of the prediction year. This study showed that the performance of an ANN-based disease prediction model was improved by applying suitable machine learning techniques together with the optimization of hyperparameter tuning involving input data. Moreover, we highlight the importance of the systematic collection of long-term disease data.

• 대한토목학회논문집
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• 제35권3호
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• pp.691-698
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• 2015

대도시와 인접한 고속도로와 같이 교통량이 많은 경우 스모그와 산성비의 주요 원인이 되는 많은 양의 질소산화물이 발생하여 대기오염이 심각한 상황이다. 이에 최근 들어 전 세계적으로 질소산화물 제거의 중요성이 부각되고 있다. $TiO_2$는 광촉매 소재의 하나로써 질소산화물 제거에 매우 효과적이므로 대기오염의 주요 원인인 질소산화물을 제거하기 위하여 $TiO_2$ 콘크리트를 도로 구조물에 적용하는 방안이 있다. 이에 본 실험적 연구에서는 $TiO_2$ 콘크리트의 현장 적용을 위하여 공용에 따른 질소산화물 제거 효율변화와 함께 환경 하중 저항성을 평가하였다. 이로 인해 $TiO_2$ 콘크리트의 장기적인 기능성 유지가 확인되었으며, 인접 도로 구조물에 적용이 타당할 것으로 판단된다.

• 디지털융복합연구
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• 제17권9호
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• pp.231-240
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• 2019

본 연구는 요양병원 간호사의 환자안전문화 인식, 표준주의 지식 및 수행도와의 관계를 파악하기 위해 실시된 서술적 조사연구이다. 요양병원 간호사 134명을 대상으로 2018년 1월 2일부터 6월 4일까지 자료수집이 이루어졌으며, 수집된 자료 분석은 SPSS/WIN 21.0프로그램을 이용하여 t-test, ANOVA, Scheffe's test, Pearson's correlation coefficient으로 하였다. 환자안전문화 인식은 표준주의 지식(r=.192, p=.027), 표준주의 수행도(r=.211, p=.014)와 유의한 양의 상관관계가 있는 것으로 나타났다. 요양병원 간호사의 환자안전문화 정착과 표준주의 수행 증진을 위해서는 체계적인 교육을 통해 표준주의 지식을 함양하고 긍정적인 환자안전문화를 조성할 수 있도록 하여 그 속에서 환자안전과 의료관련감염 관리의 중요성을 스스로 인식하고 실천하도록 해야 갈 것이다.

• 중소기업연구
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• 제39권1호
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• pp.59-87
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• 2017

최근 환경에 대한 인식이 높아지면서 그린공급사슬관리(GSCM)에 관한 관심이 증가되고 있다. GSCM에 관한 실무적 관심이 증가함에 따라 학계에서도 환경경영에 관한 학술적 연구들이 다양한 관점에서 제시되고 있다. 그런데 대부분의 연구는 주로 대기업인 모기업 중심으로 1차 협력기업과의 관계를 연구대상으로 제시하고 있다. 1차 협력사는 공급사슬채널의 중간에 위치하고 있어 환경경영에 결정적인 역할을 담당하고 있다. 본 연구는 1차 협력사를 중심으로 기업의 기업 간 장기적 관계 지향성이 그린공급사슬관리와 성과에 미치는 영향을 분석하였다. 대·중소기업 그린 파트너십과 대·중소기업 탄소파트너십 프로그램에 참여하고 있는 1차 협력기업을 대상으로 수집한 설문 조사결과를 구조방정식을 활용하여 연구모형과 가설을 검증하였다. 분석결과 첫째, 기업 간 장기적 관계지향성이 GSCM 실행 요소인 환경정보협력, 그린구매 그리고 그린제품설계를 촉진하는 요인으로 밝혀졌다. 또한 GSCM의 하위변수 간의 상호 관련성을 추가적으로 분석한 결과 환경정보 협력이 그린구매와 그린제품설계에 영향을 주는 것으로 확인되었다. 둘째, GSCM 실행 요소인 그린구매, 그린제품설계는 환경성과에 긍정적으로 영향을 미치나 환경정보협력은 환경성과에 직접적인 영향을 미치지 못하는 것으로 밝혀졌다.

• Nuclear Engineering and Technology
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• 제38권6호
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• pp.459-482
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• 2006

A geochemical approach to the long-term safety of waste disposal is discussed in connection with the significance of actinides, which shall deliver the major radioactivity inventory subsequent to the relatively short-term decay of fission products. Every power reactor generates transuranic (TRU) elements: plutonium and minor actinides (Np, Am, Cm), which consist chiefly of long-lived nuclides emitting alpha radiation. The amount of TRU actinides generated in a fuel life period is found to be relatively small (about 1 wt% or less in spent fuel) but their radioactivity persists many hundred thousands years. Geological confinement of waste containing TRU actinides demands, as a result, fundamental knowledge on the geochemical behavior of actinides in the repository environment for a long period of time. Appraisal of the scientific progress in this subject area is the main objective of the present paper. Following the introductory discussion on natural radioactivities, the nuclear fuel cycle is briefly brought up with reference to actinide generation and waste disposal. As the long-term disposal safety concerns inevitably with actinides, the significance of the aquatic actinide chemistry is summarized in two parts: the fundamental properties relevant to their aquatic behavior and the geochemical reactions in nanoscopic scale. The constrained space of writing allows discussion on some examples only, for which topics of the primary concern are selected, e.g. apparent solubility and colloid generation, colloid-facilitated migration, notable speciation of such processes, etc. Discussion is summed up to end with how to make a geochemical approach available for the long-term disposal safety of nuclear waste or for the performance assessment (PA) as known generally.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.320-320
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• 2010

The dye-sensitized solar cells (DSSCs) have achieved so far the highest validated efficiency over 11%. However, the cells with the best performance utilize volatile solvent as a electrolyte, which can cause some practical limitations for the long-term operation. This is one of the most substantial problems to be resolved for the commercialization of DSSCs. In order to improve the long-term stability, many research groups have reported new electrolyte system, to replace the liquid type electrolyte by non-volatile ones. In this work, we studied long-term stability of the DSSCs with various types of electrolytes such as (PVDF HFP) based polymer, eutectic melts of ionic liquids, and liquid based solvent. The cells with various electrolytes have been exposed to the condition under thermal stress and illumination over 1000 hours. We will report the change of photovoltaic properties with time and investigate the degradation mechanism with the impedance spectroscopic analysis.