• 한국환경보건학회지
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• 제44권5호
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• pp.460-467
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• 2018

Objectives: The objectives of this study are to estimate the inhalation exposure level of benzene for workers using Tier 1 exposure models ECETOC TRA (European Center for Ecotoxicology and Toxicology of Chemicals Target Risk Assessment) and Stoffenmanager, and to investigate their reliability for exposure assessment in K-REACH. Methods: Two exposure scenarios, 'manufacture of benzene' and 'use as solvents,' were developed for assessment of workers' exposure to benzene. The Process Category (PROC) for ECETOC TRA was collected from the European Chemical Agency (ECHA) registration dossier, and the Activity for Stoffenmanager was converted from PROC using translation of exposure models (TREXMO). The information related to exposure, such as working duration, Respiratory Protective Equipment (RPE), Local Exhaust Ventilation (LEV), and Risk Management Measure (RMM) were classified into high, medium, and low exposure conditions. The risk was determined by the ratio of the estimated exposure and occupational exposure limits of benzene. Results: Under high exposure conditions, the worker exposure level calculated from all PROCs and Activities exceeded the risk level, with the exception of PROC 1 and Activity 1. In the medium exposure condition, PROC 8a, 8b, and 9 and Activity 3, 7, and 8 all exceeded the risk, whereas in the low condition, all PROCs and Activities were determined to be safe. As a result, action corresponding with the low exposure condition is required to reduce the risk of exposure among workers in workplaces where benzene is manufactured or used as a solvent. In addition, the predicted exposure levels derived from the exposure models were lower than measured levels. The exposure levels estimated from Stoffenmanager were more conservative than those from ECETOC TRA. Conclusions: This study demonstrates the feasibility of exposure models for exposure assessment through the example of occupational inhalation exposure assessment for benzene. For more active utilization of exposure models in K-REACH, the exact application of collected information and accurate interpretation of obtained results are necessary.

• 한국환경보건학회지
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• 제47권5호
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• pp.432-445
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• 2021

Background: The European Centre for Ecotoxicology and Toxicology of Chemicals' Targeted Risk Assessment (ECETOC TRA) tool has been recognized by EU REACH as a preferred approach for calculating worker health risks from chemicals. Objectives: The applicability of the ECETOC TRA to occupational exposure estimation from industrial uses of methanol was studied by inputting surveyed and varied parameters for TRA estimation as well as through comparison with measured data. Methods: Information on uses of methanol was collected from seven working environment monitoring reports along with the measured exposure data. Input parameters for TRA estimation such as operating conditions (OCs), risk management measures (RMMs) and process categories (PROCs) were surveyed. To compare with measured exposures, parameters from the surveyed conditions of ventilation but no use of respiratory protection were applied. Results: PROCs 4, 5, 8a, 10, and 15 were assigned to ten uses of methanol. The uses include as a solvent for manufacturing sun cream, surfactants, dyestuffs, films and adhesives. Methanol was also used as a component in a release agent, hardening media and mold wash for cast products as well as a component of hard-coating solution and a viscosity-controlling agent for manufacturing glass lenses. PROC 8a and PROC 10 of a cast product manufacturer without LEV (local exhaust ventilation) and general ventilation as well as no respiratory protection resulted in the highest exposure to methanol. Assuming the identical worst OCs and RMMs for all uses, exposures from PROC 5, 8a, and 10 were the same and the highest followed by PROC 4 and 15. The estimation resulted in higher exposures in nine uses except one use where measured exposure approximated exposures without RMMs. Conclusions: The role of ECETOC TRA as a conservative exposure assessment tool was confirmed by comparison with measured data. Moreover, it can guide which RMMs should be applied for the safe use of methanol.

• 한국전통조경학회지
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• 제29권4호
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• pp.159-169
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• 2011

본 연구는 신라시대 이래 일반 민중들에게 가장 영향력이 컸던 경전 속의 땅 극락정토가 사찰에 어떠한 모습으로 현현되고 있는지를 밝히기 위한 목적으로 진행되었다. 본 연구에서는 우선 극락정토에 대한 연구동향을 살펴 본 논문의 성격을 분명히 하였으며, 정토사상의 소의경전인 관무량수경에서 설해지고 있는 극락정토의 7가지의 경관상과 그것을 그림으로 표현한 관경변상도의 내용을 현실적으로 해석하였다. 다음으로는 우리나라 사찰 가운데에서 정토사상에 근거하여 지어진 정토계(미타계) 사찰에서 극락정토의 수승한 경관이 어떻게 현현되었는지를 규명하는 단계로 진행되었다. 연구의 결과, 한국의 정토계 사찰에서는 관무량수경에서 관한 극락정토의 수승한 경관을 실제 사찰의 경관으로 현현하고 있음을 발견할 수 있었다. 그러나 연구대상사찰에서 나타나는 이러한 경관요소나 경관성은 한국의 사찰에서 흔히 나타나는 것일 수도 있어서 관무량수경의 내용이 정토계 사찰에서만 나타나는 특징적인 현상으로 보기는 어려웠다. 그렇지만 부석사와 용연사에서 발견되는 서방에 대한 의미 부여, 여러 사찰에서 나타나는 계류에 놓인 다리의 명칭, 석단이나 계단에 적용된 법수, 누각의 명칭 등은 관무량수경의 내용을 현실적으로 보여주는 정토계 사찰이 가지는 독특한 현상으로 파악되었다. 본 연구의 결과에서 특별히 주목하고자 하는 것은 관무량수경이나 관경변상도에서 적극적으로 강조되고 있고, 또한 빠짐없이 표현되고 있는 연지는 그 사례를 연구대상사찰에서 찾아보기 어려워, 지금까지 정토계 사찰에서 연지가 예외 없이 조성되었을 것이라는 생각은 수정되어야 한다는 것으로 이에 대한 연구는 앞으로 지속되어야 할 것으로 본다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.667-670
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• 1998

Novel bipolar transresistance amplifier(TRA) for high-accuracy current-mode signal processing is described. The TRA consists of two current follower for the current inputs, a current summer for curent-differential, and a voltage follower for the voltage output. The simulation results show that the impedence of the current input and the voltage output is 0.5 $\Omega$ and the 3-dB cutoff frequency when used as a current to voltage converter extends beyond 40 MHz.

• 시스템엔지니어링학술지
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• 제5권2호
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• pp.43-48
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• 2009

This paper aims to develop the framework for evaluating the technology maturity by utilizing TRA(Technology Readiness Assessment) approach. In this context, we will provide the directions through analyzing the domestic acquisition process and re lated regulations, and clarify the scenarios to apply the proposed framework to the defense R&D programs. The paper will conclude with the case study for the evolution of the proposed framework.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2000년도 추계학술대회 논문집
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• pp.375-376
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• 2000

산업화나 도시화에 따른 인위적인 토지 이용의 변경은 최근들어 더욱 빈번하고 광범위하게 나타나고 있는 실정이다. 이러한 토지 이용의 변경은 도시계획이나 건축, 공단의 조성, 녹지 변경등의 형태로 나타나고 있으며 이는 국지 기후나 환경을 변화시키는 결과를 가져오기도 한다. 미세 국지 기후의 변화는 지구규모의 기후변화와는 다른 양상을 띠고 발달되며 또한 시ㆍ공간적인 변화가 빠르고 인간에게 미치는 영향은 매우 직접적이다. 이에 따라 미세 국지 기후의 변화와 그 영향은 도시 환경 문제와 관련하여 기상학자들의 관심사로 부각되게 되었다. (중략)

• 한국응용과학기술학회지
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• 제26권1호
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• pp.1-9
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• 2009

Nowadays, Tra catfish fat is given attention as an appropriate material for biodiesel production in Vietnam. The aim of this work is to investigate the optimal conditions of refining biodiesel and recovering glycerin by the transesterification from Tra catfish fat using KOH catalyst. As our results, the yield of transesterification was achieved to 94.17% at $50^{\circ}C$ for 45 min with 6:1 molar ratio of methanol to fat in the presence of 0.8% KOH catalyst, and wherein the biodiesel was refined by washing with distilled water at $70^{\circ}C$ and dried in a microwave oven. The yield of raw glycerin recoveries from the transesterification process was 78.58%. The purity of raw glycerin was 84.14% by the conditions of neutralization state with $H_{3}PO_{4}$ solution (pH = 5), $70^{\circ}C$, and 60 min. Activated carbon (3.0 wt.%) was used for the bleaching process at $80^{\circ}C$ for 20 min. The biodiesel was obtained in accordance with for ASTM D 6751 (biodiesel standard). The ash and water of raw glycerins were 7.32 and 8.01%, respectively, and implied that the raw glycerin is very promising candidate to be used as a raw material for textile and cosmetic industries.

• 복식
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• 제26권
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• pp.289-310
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• 1995

The present study aims at investigating the style change of the Korean women's traditional costume and analyzing its character in accordance with the social changes during the period from the civilization in 1884 to the present. The design of the tranditional costume which might be formed in the era of the Three Kingdoms had been slowly modified, and the Korean jacket and skirt design was settled in the Chosun period. In the end of the Chosun period, the drastic social changes such as civilization and revolution, together with the introduction of western dresses, affected strongly the traditional costume design. This led to a change from the old dress design to the stylish and practical one because civilized women and high school girls wore the modified costume composed of long jacket and short skirt or western style dresses. In recent years after 1960's Korean women usually wore traditional costumes as ceremonial dresses be-cause the western style dresses replaced the tra-ditional costume in everyday life. After 1970's, however, the A-line silhouette, combined with ornaments, adapted to the traditional costume in order to emphasize women's beauty, thereby resulting in remarkable modification in the tra-ditional costume. In those days, the large pro-duction of various textiles such as nylon and tetron and the appearance of the traditional costume designers played an important role in developing beautiful traditional costume designs and bringing closer together with general public women. These recent design changes might be classified generally by the following three stages ; (1) "the period of settlement" (1965 1975), (2) "the period of maturity" (1976 1985), and (3) "the period of stabilization" (1986 1995). The costume design of each period was discussed and compared in detail according to historical events. From this study, inherent beauty of the Korean traditional costume can be recognized again, and clarified its position as our folkdress. It is also suggested that in future its modification should be achieved continuously in accordance with tra-dition and modern sense.h tra-dition and modern sense.

• 컴퓨터교육학회논문지
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• 제8권6호
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• pp.55-63
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• 2005

본 연구에서는 컴퓨터 실습교육 학습자의 관점에서 교육학에서의 Holton이론과 심리학에서의 TRA(Theory of Reasoned Action)을 통합 적용하여 이들의 학습 성과에 영향을 미치는 요인들을 탐색하였다. 서울 소재 총7개의 실업계 고둥학교를 대상으로 604개의 유효설문 자료를 수집하였으며, 분석방법으로는 사회과학에서 원용되고 있는 구조방정식모델을 적용하였다. 구조방정식모델 분석을 통해 나타난 연구결과는 연구모형에서 제안한 바대로 학습자반응, 학습자동기, 학습자능력, 주관적 규범, 학습자태도, 학습내용, 학습의도, 학습행위가 모두 학습 성과에 영향을 미치는 것으로 나타났다. 본 연구는 심리학 및 교육학에서 각각 적용되어 온 TRA 이론과 Holton 이론의 통합을 시도함으로써 학습 성과를 결정할 수 있는 요인들을 규명한 측면에서 학술적 시사점을 찾을 수 있다. 또한 실무적인 측면에서는 본 연구의 분석결과를 토대로 향후 컴퓨터 실습교육의 효과적인 운영과 문제점 개선에 도움이 될 것으로 기대할 수 있다.

• 산업진흥연구
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• 제1권1호
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• pp.41-49
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• 2016

본 합리적 행동이론(TRA)과 기술수용이론 (TAM)을 기반으로, SMEs가 벤처지원정책을 수용하는 요인이 무엇인지를 밝히고, 정부가 효율적 방법으로 정책 지원하고 있는지를 알아보며, 지속성의 관점에서 SMEs를 위한, 효율적인 벤처정책 지원 방향을 제시하고 있다. 주요 결과를 살펴보면, 첫째, Experience가 Ease of Use에 영향이 있었고, 둘째, EASE of Use가 Usefulness는 영향이 있지만, Intention to Use에 대하여 영향이 없었으며, 셋째, Usefulness가 Intention to Use 에 직접적 매우 강한 영향을 미치고 있을 뿐 아니라, 다른 많은 변수를 매개하고 있다는 것을 알 수 있다. 한편, 정책 수용 의지 (Intention to use)에 영향을 미치는 요인을 분석한 결과, Output Quality가 Usefulness에 영향을 미치고 있음을 알 수 있었다. 이는 정책수행의 결과가 선택하고 수행 할 때는 기업 입장에서 이해득실에 대한 많은 것을 고려 하고 있는 지극히 이성적으로 행동하는 기업이라는 것을 알 수 있다.