• 대한화학회지
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• 제65권2호
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• pp.145-150
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• 2021

The present study describes a hands-on experiment to help students understand the concept of phase change or phase transition and its application in a phase change material (PCM). PCMs are substances that have the capability of storing and releasing large amounts of thermal energy. They act as energy storage materials that provide an effective way to save energy by reducing the electricity required for heating and cooling. Lauric acid (LA) was selected as an example of the PCM. Students investigated the temperature change of LA and the temperature (of air) inside the test tube. The differences in the temperatures of the systems helped students understand how PCMs work. A one-group pretest and posttest design was implemented with 34 grade-11 students in science and mathematics. Students' understanding was assessed using a multiple-choice test and a questionnaire. The findings revealed that the designed activity helped students understand the concept of phase change and its application to materials for thermal energy storage.

• 대한공업교육학회지
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• 제45권2호
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• pp.1-20
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• 2020

이 연구의 목적은 화학공업을 공부하는 학생들이 액위제어를 쉽게 이해할 수 있도록 하기 위해, 조립형 액위제어 실험장치를 제작하고 이를 수업에 적용할 수 있는 체험활동과제를 개발하는 것이다. 이를 위해 2015 개정 교육과정 화학공업 실무과목에서 액위제어와 관련된 내용요소를 분석하여, 조립형 액위제어 실험장치를 활용하는 체험 활동과제를 개발하여 전문가 검증을 마친 후, 16차시의 체험활동과제를 S 마이스터고등학교 학생 19명에게 적용하였다. 이 연구에서 얻은 결과는 다음과 같다. 첫째, 기존 완성형 액위제어 실험장치를 분석하고, 이를 토대로 학생 수준에서 조립 가능하며 실습에 활용할 수 있는 새로운 조립형 액위제어 실험장치를 설계·제작하였다. 둘째. 2015 개정 교육과정의 NCS기반 '화학공정유지운영' 실무과목의 내용을 분석하여 액위제어와 관련된 학습 내용들을 추출하였다. 이 액위제어 관련 내용 중에서 공정 흐름도의 이해, 액위제어 실험장치 제작, 유량 측정, 액위제어 현상 확인 등의 실습을 위 조립형 액위제어 실험장치로 진행하여 액위제어 관련 내용을 체계적으로 학습할 수 있도록 하였다.

• 대한공업교육학회지
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• 제39권1호
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• pp.227-246
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• 2014

이 연구의 목적은 창의적 체험활동의 하위 영역인 동아리활동에 대한 공업계 고등학교 교사들의 인식을 조사하여, 향후 공업계 고등학교의 특성에 맞는 창의적 체험활동을 할 수 있도록 바람직한 방향을 제시하는데 필요한 기초 자료를 제공하는 것이다. 이 연구의 응답자는 전국의 공업계 고등학교에 재직 중인 교사 393명이고, 동아리활동에 대한 5개 영역 32개 분야의 문항(중요도, 반영도)으로 구성된 설문지를 활용하였다. 연구의 결과는 다음과 같다. 첫째, 동아리활동 영역에서 중요도 분석 결과, '학술 활동'은 '발명', '문화 예술 활 동'은 '영상예술', '스포츠 활동'은 '도전활동', '실습 노작 활동'은 '학교 특성화 전공', '청소년 단체 활동'은 '스카우트연맹'과 '청소년적십자'가 가장 높게 나타났다. 둘째, 동아리활동의 영역에서 반영도 분석 결과 '학술 활동', '문화 예술 활동' 및 '스포츠 활동' 영역은 대체적으로 공업계 고등학교 교사들이 생각하는 중요도에 비슷하게 반영되고 있었다. 하지만 '학교 특성화 전공'을 제외한 '실습 노작 활동'과 '청소년 단체 활동'의 경우는 중요도와는 별개로 모든 분야가 잘 반영되지 않고 있는 것으로 나타났다. '실습 노작 활동'은 중요도 분석과 반영도 분석이 비슷하게 나타났지만 '청소년 단체 활동'은 중요도에 비해 반영도 값이 현저히 낮게 나타나 중요도와 반영도에 큰 차이가 있었다.

• 한국초등과학교육학회지:초등과학교육
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• 제33권1호
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• pp.21-29
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• 2014

This study analyzed the inquiry activities in the 'matter' units from each science textbook for the fifth and the sixth graders developed by the 2007 revised national curriculum, using Practical Activity Analysis Inventory proposed by Millar(2009) to examine types of learning objectives, hands-on contents(what students have to do with objects and materials), minds-on contents(what students have to 'do' with ideas), and logical structure each activity had. The results of this study are as follows: First, most learning objectives of the inquiry activities seems to be suitable for the standards of 2007 revised national curriculum. Second, the standards of 2007 revised national curriculum are properly reflected in hands-on contents of inquiry activities. Third, minds-on contents of inquiry activities are well developed to meet the standards of 2007 revised national curriculum as a whole. Fourth, the logical structures of inquiry activities are mostly adequate for achieving the goals of the 2007 revised national curriculum. In the textbook for the fifth graders, however, all the activities are focusing too much on using students' current ideas to generate a prediction and collecting data to explore or test it. Based on these findings, this research has concluded that learning objectives, minds-on contents and logical structures of inquiry activities need to be designed carefully for students to be exposed to various activities when developing following textbooks.

• 여성건강간호학회지
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• 제20권3호
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• pp.215-224
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• 2014

Purpose: The study was to survey personal hygiene practice related to genito-urinary tract and menstrual hygiene management in female adolescents in order to obtain basic information for health education. Methods: With a descriptive survey design, 389 adolescents were recruited via convenience sampling in Korea. Survey instrument was the feminine and menstrual hygiene practice and perception of vaginal douching. Data were collected from a self-administered structured questionnaire. Results: Mean age of adolescents was 16.09 and menarche was at 13.21. While washing hands after urination/defecation was highly performed, wipe front to back and wash with soap and water were reported as being not well done. Twenty-eight percent reported douching habit. More positive beliefs about douching were reported by adolescents who practiced douching. Menstrual hygiene management was very appropriate with changing sanitary pads regularly with hand washing; but less performed for limiting bathing activity during menstrual periods and washing hands after activity of genito-urinary area. Conclusion: Some adolescents practiced inadequate hygiene practices especially for body cleansing during menstrual period and vaginal douching. It is important to develop and implement school health education programs on feminine and personal hygiene for adolescents to help them perform adequate health behaviors.

• 대한인간공학회지
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• 제3권1호
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• pp.19-24
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• 1984

As in dynamic muscular activity, to support one's body may be regarded as the static workload. An examination is made of the relationship between heart rate and oxygen uptake of three male graduate students in static working postures (sitting, squatting and standing). Though it has been believed that there exists a linear relationship between heart rate and oxygen uptake, this thesis shows that both have no relationship in the case of static postures, and that they may depend upon the characteristics of postures rather than the static workload. These results are discussed analytically. The additivity between static body postures and holding up one's hands at his maximum height is tested. Compared with the sum of energy expenditure in balancing one's body and holding up hands, the net rate of energy expenditure in performing them simultaneously is equivalent. In the case of static postures, the importance of the awareness of the characteristics and relevance of the measures is discussed.

• 전기학회논문지
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• 제57권12호
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• pp.2336-2344
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• 2008

In this paper, muscular activity and muscle fatigue of FDI(first dorsal interosseous muscle) and thenar muscle of hand was analyzed with surface EMG signal based on four kinds of attitudes(grip, tip, key and palmar) to measure grip strength and pinch strength after hand operation and rehabilitation treatment. The normative data are needed to interpret evaluation data to assess a patient's ability to return to labor environment. The preceding researchers proposed the standard data only by studying on maximum grip strength and the maximum pinch strength followed by each attitude of subjects' hands. But in this study, the muscle activity and muscle fatigue were considered under the various attitude to propose normative data. As a results, the muscle fatigue may be used only for presentation of normative data in labor environment.

• 한국식품조리과학회지
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• 제23권3호통권99호
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• pp.321-326
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• 2007

The microbial contamination levels of school classrooms were assessed as foodservice environments for elementary students. Two elementary schools located in Kyunggi-do were selected, and the total plate counts (TPC) and coliforms were measured from the classroom facilities, including the tables, chairs, floors, shelves, doors, as well as the hands of students, and the air of classrooms. The TPC of the classroom facilities were relatively low ranging from 2.30 to 3.79 log CFU/100 cm$^2$. The TPC counts from the hands of serving students and served students, were 6.39 and 5.33 log CFU, respectively, and the TPC counts of the foodservice utensils were <3.00 log CFU/ea before use and 4.77 CFU/ea after use. The air samples of 'empty classrooms during physical education', 'after physical education class', and 'during lunch' showed the contamination levels of 26 CFU/m$^3$,392 CFU/m$^3$, 364 CFU/m$^3$, respectively, suggesting that the microbial levels in the air varies greatly depending on the class activity before foodservice. When the TPCs of the air during lunch were measured from 18 classrooms, the levels ranged from 76 to >2228 CFU/m$^3$. Coliforms were not detected in the classroom facilities; however, air samples of the classrooms showed 1${\sim}$2 CFU/m$^3$. The above results show that classroom air and the hands of students, can have high levels of microbial contamination, which must to be controlled for safer school foodservice.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제2권1호
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• pp.49-54
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• 2013

스마트폰 가속도 센서를 이용한 사용자 행위 인식은 동일한 행위를 수행하더라도 사용자마다 가속도 데이터 패턴이 서로 달라지는 사용자 의존성 문제를 가지고 있다. 그뿐만 아니라 스마트폰은 사용자의 어느 주머니나 손에도 놓일 수 있기 때문에 위치 의존성 문제도 지니고 있다. 본 논문에서는 특정 사용자나 특정 폰 위치에 대한 의존성이 적은 효과적인 행위 인식 방법을 제안한다. 제안한 방법을 기초로 안드로이드 스마트폰에서 동작하는 실시간 행위 인식 시스템을 구현하였다. 서로 다른 사용자와 서로 다른 폰 위치로부터 수집한 총 6642개의 샘플들을 이용한 실험을 통해, 본 논문에서 제안한 행위 인식 시스템의 성능을 분석하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.861-864
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• 2011

Since national GHG reduction target by 2020 has been presented in Korea, the role of railroad has been reinforced within transport system due to the allocation of reduction target into sector. So, it is necessary to manage activity data systematically for the calculation of GHG emission in railroad. Now, the activity data of diesel consumption for NIR(National Inventory Report) are provided from oil supply and demand statistics. On the other hands, the activity data collected directly from railroad operating companies are used for GHG & Energy Target Management Act. This study aimed to assess the GHG emissions using two kinds of activity data related to the diesel consumption of railroad in 2009 and 2010. As a result, GHG emissions based on oil supply and demand statistics was 636 thousands ton $CO_{2e}$, but the activity data collected from railroad operating companies showed 649 thousands ton $CO_{2e}$ in 2009. Also, the gap of $CO_{2e}$ emission was increased in 2010. These trends were caused because oil supply and demand statistics included total diesel sales volume during 1 year and the activity data collected from railroad operating companies were the amount of diesel consumption only at railcar operation and maintenance step. In conclusion, it is important to develop the management and verification system of activity data with high reliability to substitute oil supply and demand statistics in railroad sector.