• 한국정보통신학회논문지
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• 제14권5호
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• pp.1078-1084
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• 2010

본 논문에서는 오차역전파알고리즘에 의한 신경회로망을 사용하여 이산푸리에변환에 의한 진폭성분과 위상 성분을 복원하는 음성강조 시스템을 제안한다. 먼저, 신경회로망이 잡음이 부가된 음성신호의 이산푸리에변환의 진폭성분과 위상성분을 사용하여 학습된 후, 제안한 시스템은 백색잡음에 의하여 열화된 잡음이 부가된 음성 신호를 강조한다. 백색잡음에 의하여 열화된 음성신호는 이산푸리에변환에 의한 진폭성분과 위상성분을 입력으로 하는 신경회로망을 사용하여 제안된 시스템에 의하여 강조되는 것을 실험결과로 증명한다. 제안한 시스템은 스펙트럼 왜곡율의 평가법을 사용하여 백색잡음에 의하여 열화된 음성신호에 대하여 효과적인 것을 실험으로 확인한다.

• 대한안전경영과학회지
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• 제19권4호
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• pp.189-208
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• 2017

This study is for figuring out major components of construction quality infrastructure and suggesting improvement plan by benchmarking global best practice model and analyzing gap between the model and sample practice. Based on improvement plan, researcher could derive major characters and components of construction quality infrastructure, and also about the priority among core competency components of construction quality experts. The result showed that the 'human resource' was ranked the best priority followed by 'method' 'environment', 'equipment' among major characters and components of construction quality infrastructure. Also, for core competency components of construction quality experts, 'number of years in work places' was the best priority, and the 'professional knowledge on engineering' was another priority ranked. Far from general perception on competency components, 'academic education' ranked the last. It may allude that the current education system in this country is not effective in developing competency of quality engineers. In summary, this study shows professionalism of quality engineer is the most important thing in all the components.

• 한국식생활문화학회지
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• 제36권3호
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• pp.317-324
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• 2021

This study was carried out to investigate the flavoral essential oil components in the stems of Agastache rugosa. These components were analyzed using gas chromatography-mass selective detector (GC-MSD). The stems of Agastache rugosa were contained alcohols, aldehydes, ketones, fatty acid esters, and terpenoids. The peak area (%) of estragole was highest among its oil components and the next were pulegone and menthone. The terpenoid alcohols found were 1-octen-3-ol, chavicol, spatulenol, 3-hexen-1-ol, 2-cyclohexen-1-ol, methyl eugenol, and octaethyllene glycol. The stems also contained ketones such as pulegone, menthone, cis-isopulegone, 2-cyclohexene-1-one, 3-octanone, 1-cyclohexanone, isoindole-1-one, t-ionone, inden-2-one, as well as the aldehydes of 4-methoxycinnam and benzaldehyde. The following esters were also detected 1-isopulegone-3-yl acetate, caryophyllene oxide, acetate and benzendicarboxylic acid ester. The terpenoids in the stems were identified as caryophyllene, limonene, cyclohexasiloxane-D, germacrene-D, anethole, cadinene, muurolene, and bourbonene. Overall Agastache rugosa contained several functional oil components including phenylpropanoids and terpenoids as flavoral essential oil components for natural aromatherapy.

• 복식문화연구
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• 제28권6호
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• pp.801-814
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• 2020

The purpose of this study was to explore the importance level, the present level, and the educational need for 21 business ethics components among 2-year and 4-year college students majoring in fashion. Survey data of 364 students (128 students of 2-year colleges and 238 students of 4-year colleges) were analyzed through descriptive statistics, Borich's needs assessment for education, The Locus for Focus model, exploratory factor analysis, and t-test. The results showed five business ethics components ranked highly as educational needs among college students: 'reducing waste', 'using vegan materials', 'using human-friendly materials', 'strengthening sustainable technologies', and 'promoting workers' rights'. Those components should be integrated into curricula of fashion majors in colleges. Students in 4-year colleges considered most of 21 business ethics components as more important than did students at 2-year colleges. More needs for education were observed by 4-year college students in eight business ethics components than by 2-year college students. In addition, a positive attitude toward business ethics education and the suitability of business ethics education were higher among 4-year college students than 2-year college students. Results provide a guideline for business ethics education by indicating a list of business ethics components that urgently needed to be adapted to fashion curricula according to each college type.

• 산업경영시스템학회지
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• 제44권4호
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• pp.98-105
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• 2021

Using the frequency-based decomposition, I decompose the consumption growth to explain well-known patterns of stock returns in the Korean market. To be more specific, the consumption growth is decomposed by its half-life of shocks. The component over four years of half-life is called the business-cycle consumption component, and the components with half-lives under four years are short-run components. I compute the long-run and short-run components of stock excess returns as well and use component-by-component sensitivities to price stock portfolios. As a result, the business-cycle consumption risk with half-life of over four years is useful in explaining the cross-section of size-book-to-market portfolios and size-momentum portfolios in the Korean stock market. The short-run components have their own pricing abilities with mixed direction, so that the restricted one short-term factor model is rejected. The explanatory power with short- and long-run components is comparable to that of the Fama-French three-factor model. The components with one- to four-year half-lives are also helpful in explaining the returns. The results about the long-run components emphasize the importance of long-run component in consumption growth to explain the asset returns.

• 한국산업융합학회 논문집
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• 제25권6_3호
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• pp.1315-1324
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• 2022

The need for remanufacturing ships and various mechanical components continues to increase along with environmental problems. Research on remanufacturing is being carried out in various fields, but research on cleaning is quite insufficient. In particular, there is no research on the cleaning-ability of diverse mechanical components. In order to increase the life cycle of mechanical components, remanufacturing must be considered from the step of design. Particularly, it is also very important to evaluate the degree of easiness in cleaning to remove various pollutants generated by long-term use quickly as well as easily. In this study, the degree of easiness in cleaning is defined as cleaning-ability. In fact, remanufacturing components can be easily done only when cleaning-ability is set high from the step of design. The purpose of this study is to evaluate the cleaning-ability of ships and various mechanical components. The details of easiness in cleaning are cleaning and drying identification, accessibility to cleaning tools, convenience in cleaning, and convenience in drying. This study presents a quantitative procedure to evaluate cleaning-ability, derived various factors influencing each of the details of easiness and their ranges, and gave scores to the factors according to their ranges. The weight was also calculated for the details of easiness in cleaning and the factors. Lastly, this researcher suggests a scoring procedure to evaluate cleaning-ability quantitatively and the total weight of cleaning-ability.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.863-870
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• 2022

Unsatisfactory urban walking environment stresses urban residents, and may cause mental illness and chronic diseases by reducing walking activities. Therefore, establishing a high-quality walking environment that can promote walking activities in urban residents has emerged as an important issue. The walking environment consists of various components, such as trees, stairs, streetlights, benches, signs, fences, and facilities, and it is essential to understand which components and their settings act as satisfiers or dissatisfiers for pedestrians, to create a better quality walking environment. Therefore, this study investigated pedestrian satisfaction and dissatisfaction as a function of various environmental components through a survey using walking environment images. The results revealed that most of the walking environment components except the braille block and treezone exhibited significant correlations with pedestrian satisfaction. Particularly, safety-related component (e.g., adjacent roads, parked cars, traffic cushions, and car separation), and landscape-related components (e.g., trees and green), as well as the material settings of landscape facilities (e.g., wooden fences, benches, stairs, and walkway surfaces) correlated with pedestrian satisfaction. The results of this study can contribute to the extraction of useful features to evaluate pedestrian satisfaction as a function of the walking environment. The research outcome is expected to assist in the effective arrangement of walking environment components and their settings, which will ultimately contribute to significantly satisfactory walking environment and encourage walking activities.

• Wind and Structures
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• 제38권4호
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• pp.277-293
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• 2024

The recorded thunderstorm winds at a point contain tri-directional components. The probabilistic characteristics of such recorded winds in terms of instantaneous mean wind speed and direction, and the probability distribution and the time-frequency dependent crossed and non-crossed power spectral density functions for the high-frequency fluctuating wind components are unclear. In the present study, we analyze the recorded tri-directional thunderstorm wind components by separating the recorded winds in terms of low-frequency time-varying mean wind speed and high-frequency fluctuating wind components in the alongwind direction and two orthogonal crosswind directions. We determine the time-varying mean wind speed and direction defined by azimuth and elevation angles, and analyze the spectra of high-frequency wind components in three orthogonal directions using continuous wavelet transforms. Additionally, we evaluate the coherence between each pair of fluctuating winds. Based on the analysis results, we develop empirical spectral models and lagged coherence models for the tri-directional fluctuating wind components, and we indicate that the fluctuating wind components can be treated as Gaussian. We show how they can be used to generate time histories of the tri-directional thunderstorm winds.

• ETRI Journal
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• 제38권4호
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• pp.675-684
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• 2016

This paper demonstrates the effect of fluoride-based plasma treatment on the performance of $Al_2O_3/AlGaN/GaN$ metal-insulator-semiconductor heterostructure field effect transistors (MISHFETs) with a T-shaped gate length of $0.20{\mu}m$. For the fabrication of the MISHFET, an $Al_2O_3$ layer as a gate dielectric was deposited using atomic layer deposition, which greatly decreases the gate leakage current, followed by the deposition of the silicon nitride layer. The silicon nitride layer on the gate foot region was then selectively removed through a reactive ion etching technique using $CF_4$ plasma. The etching process was continued for a longer period of time even after the complete removal of the silicon nitride layer to expose the $Al_2O_3$ gate dielectric layer to the plasma environment. The thickness of the $Al_2O_3$ gate dielectric layer was slowly reduced during the plasma exposure. Through this plasma treatment, the device exhibited a threshold voltage shift of 3.1 V in the positive direction, an increase of 50 mS/mm in trans conductance, a degraded off-state performance and a larger gate leakage current compared with that of the reference device without a plasma treatment.

• 한국식품과학회지
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• 제41권6호
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• pp.615-621
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• 2009

SFE법을 이용하여 딸기의 휘발성 향기성분을 추출하기 위한 시료의 적정 전처리 및 SFE 작동조건을 검토하였으며, SDE법 및 SE법 등의 추출방법과 휘발성 향기성분 조성을 비교하였다. 딸기 생시료, 동결건조시료, 그리고 생시료에 celite를 30, 70%를 혼합하여 제조한 시료를 이용하여 SFE 처리후 향기성분을 분석한 결과, 생시료에 celite를 70% 첨가하는 방법이 향기성분을 추출하는데 가장 효과적인 것으로 나타났다. 온도(40, $55^{\circ}C$)와 압력(3,000, 6,000 psi)을 달리하여 SFE 처리한 결과, 3000 psi, $55^{\circ}C$ 조건에서 alcohol류와 acid류의 추출효율이 증가하였으며, $\gamma$-dodecalactone의 함량도 3배 정도 높은 수준으로 나타났다. SDE법, SFE법 및 SE법 등의 추출방법별 딸기의 휘발성 향기성분을 분석한 결과, SFE법은 SDE법에 비해 추출한 휘발성 향기성분의 종류는 적지만 추출량이 비슷하면서 열분해 및 열변성이 발생하지 않아 딸기 고유의 향기에 가까운 향기패턴을 나타내었으며, 기호적으로 우수한 acid류가 다량 함유된 향기성분을 추출하기에 적합한 것으로 나타났다.