How to use LMOs for industrial purpose in Korea

Kyungmoon PARK 한국생물공학회 2018 한국생물공학회 학술대회 Vol.2018 No.10

Photochromic Mechanism in a-WO3 Thin Films Based on Raman Spectroscopic Studies

Kyungmoon Kim,Chungwon Seo,정현식,Se-Hee Lee 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

The photochromic mechanism in a-WO3 thin films prepared by thermal evaporation has been investigated using Raman scattering measurements. The Raman spectra of uv-irradiated thin films show a weak peak at 450 cm.1. This peak is known to be related to the gasochromic and electochromic coloration and is attributed to the formation of W5+ = O bonds. The I-V characteristic of uv-irradiated a-WO3 thin films was measured to study the change in the electrical properties due to photochromic coloration. The uv-irradiated films show enhanced conductivity due to excited carriers.

IEEE 802.11 WLAN 에서 비트 에러를 고려한 성능 향상 방안에 관한 연구

우경문 ( Kyungmoon Woo ),김종권 ( Chong-kwon Kim ) 한국정보처리학회 2006 한국정보처리학회 학술대회논문집 Vol.13 No.2

IEEE 802.11 WLAN 환경에서는 기존 유선 환경에서 발생하는 동시 전송에 의한 충돌 외에 무선 채널 상태에 따른 비트 에러로 자료 손실이 발생할 수 있다. 이런 비트 에러를 구분하여 성능 감소를 줄이기 위해 현재까지 많은 연구가 되었지만 이런 연구들은 주로 전송 속도 조절에 집중 되어 있었다. 본 논문에서는 에러 유형에 따라 발생하는 성능 감소 현상을 전송 속도 뿐만 아니라 충돌율을 조정하는 CW(Contention Window) 에도 영향을 미침을 살펴보고, 이 결과를 바탕으로 정확한 에러 원인 구분을 위한 크로스 레이어를 고려한 에러 원인 식별 방법 및 에러 유형에 따라 전송 속도와 CW 를 조절하여 에러로 인한 성능 감소를 최소화 할 수 있는 방안을 제시한다.

Behavior analysis of air bubbles in the oil lubricant of FDBs at low speed operating conditions

Jung, Kyungmoon,Lee, Jihoon,Jung, Yeonha,Jang, Hokyung,Jang, Gunhee Springer-Verlag 2013 Microsystem Technologies Vol.19 No.9

Preservice Elementary Teachers’ Images of Scientific Inquiry Regarding Practices of Next Generation Science Standards

Jeon Kyungmoon,Biggers,Mandy S 이화여자대학교 교과교육연구소 2017 교과교육학연구 Vol.21 No.3

We investigated Korean preservice elementary teachers’ mental images of science inquiry and inquiry teaching with respect to 8 specific Science and Engineering Practices (SEP). The preservice teachers had learned about science inquiry, but were not taught these SEP in their Korean curriculum. We asked them to draw and explain an imagined situation where they would be teaching science inquiry in an elementary science classroom. Some were also asked to describe an imagined situation of scientists conducting research. We applied the 8 SEPs as an analysis framework to review their images of science inquiry and inquiry teaching. The majority of students (93.2%) for elementary science teaching and all (100%) for science research represented images related to at least one SEP. However, students’ pictorial and/or written descriptions were restricted to some SEPs such as planning and carrying out investigations or analyzing and interpreting data. Although they tended to respond that asking questions and defining problems would be the most related to science inquiry among the 8 SEPs, they rarely applied those kinds of scenes to their drawings. Furthermore, using mathematics and computational thinking was hardly found in their ideas of elementary science inquiry teaching, and developing and using models was not represented as being part of scientists’ research. The findings indicate possible approaches to teachers’ professional development and suggest directions for further research.

Behavior of fluid lubricant and air–oil interface of operating FDBs due to operating condition and seal design

Jung, Kyungmoon,Jang, Gunhee,Kim, Juho Springer-Verlag 2012 Microsystem Technologies Vol.18 No.9

RFID 태그 개수 추정 방법 및 질의 시간 최소화 방안

우경문(Kyungmoon Woo),김종권(Chongkwon Kim) 한국정보과학회 2006 정보과학회논문지 : 정보통신 Vol.33 No.6

무선인식(RFID) 시스템은 기존의 바코드 시스템을 대체할 뿐만 아니라 제조, 물류, 서비스 산업 등을 변화시킬 차세대 핵심 기술 중의 하나이다. RFID 시스템은 무선으로 초당 수 백개까지의 태그정보를 인식할 수 있다. 태그 인식은 리더(reader)가 각 라운드 별로 정한 프레임 동안 태그들이 자신의 ID를 임의 전송함으로써 이루어진다. 태그 인식 시간을 감소시키려면 태그 수를 감안한 적절한 크기의 프레임을 할당해야 한다. 본 논문에서는 RFID 시스템에서 질의 시간을 최소화 할 수 있는 방법을 제안하였다. 먼저 태그 개수를 단순하면서도 효율적으로 추정하는 방법을 제안하고, 이를 이용하여 각 라운드 별로 최적 프레임 길이를 구하여 전체 질의 시간을 최소화하는 방법을 개발하였다. 기존에 제안된 방법과 성능비교를 수행하여 본 논문에서 제안하는 태그 수 추정 방법이 기존 방법보다 더 정확하고 효율적임을 관찰하였고 최적 프레임 길이 결정 문제에 또한 간단한 Greedy방법이 복잡한 최적 프레임 계산기법과 비슷한 성능을 가진다는 것을 확인하였다. An RFID system is an important technology that could replace the traditional bar code system changing the paradigm of manufacturing, distribution, and service industry. An RFID reader can recognize several hundred tags in one second. Tag identification is done by tags’ random transmission of their IDs in a frame which is assigned by the reader at each round. To minimize tag identification time, optimal frame size should be selected according to the number of tags. This paper presents new query optimization methods in RFID systems. Query optimization consists of tag number estimation problem and frame length determination problem. We propose a simple yet efficient tag estimation method and calculate optimal frame lengths that minimize overall query time. We conducted rigorous performance studies. Performance results show that the new tag number estimation technique is more accurate than previous methods. We also observe that a simple greedy method is as efficient as the optimal method in minimizing the query time.

지지구조의 유연성을 고려한 고속 유연 폴리곤 미러 스캐너 모터의 유한 요소 불평형 응답 해석

정경문(Kyungmoon Jung),서찬희(Chanhee Seo),김명규(Myunggyu Kim),장건희(Gunhee Jang) 한국소음진동공학회 2007 한국소음진동공학회 학술대회논문집 Vol.2007 No.3

과학 탐구 지도에 대한 초등학교 교사들의 인식 조사

전경문 ( Kyungmoon Jeon ) 경북대학교 과학교육연구소 2015 科學敎育硏究誌 Vol.39 No.2

본 연구에서는 초등학교 교사들의 과학 탐구 지도에 대한 인식을 조사하였다. 먼저 교사들의 탐구지도 경험에 대해 자유롭게 서술하도록 하여, 교사들이 인식하고 있는 탐구 지도 유형을 세 가지로 분류할 수 있었다. 관찰, 분류, 측정, 예상, 공정한비교 등을 강조하는 ‘과학 과정기능 중심’ 범주, 학생들이 스스로 문제를 생성하도록 하는 ‘과학 문제발견’ 범주, 그리고 제시된 절차에 따라 실험을 수행하며 과학적 개념이나 내용을 증명하는 ‘개념이나 내용 예증’ 범주이다. 다음으로 18개의 활동이 각각 적힌 카드를 ‘탐구를 통한 과학 수업’ 카드를 중심으로 한 이차원적 평면에 자유롭게 배치하도록한 후, 중심 카드와 각 카드 사이의 상대적인 거리를 측정하였다. ‘학생들이 적절한 절차를 설계하고 수행’하는 것이 탐구와 가장 밀접하게 관련 있는 활동으로 인식되고 있었다. 이러한 결과는 (예비)교사의 탐구 이해도를 증진시키기 위해 적극 활용되어야 하고, 나아가 초등학교 현장에서 탐구를 통한 과학교육이 보다 활성화되어야 할 것이다. This study explored elementary school teachers’ perspectives on science inquiry teaching. First, an open-ended questionnaire was administered to elicit teachers’ experiences of their approach to inquiry teaching. These self-reported approaches revealed three conceptions of teaching for inquiry learning in science: ‘science process skills-centered’ category focused on observing, classifying, measuring, and fair testing; ‘generating scientific questions’ category focused on students’ question-generating; and ‘illustrate concept and/or content’ category focused on science content demonstration by making use of experimental procedures to obtain expected results. Second, teachers were asked to place 18 activity cards either close to or further from an ‘inquiry-based science classroom’ card. The relative distances from the activity card to the central classroom card were measured. The teachers perceived that students’ activity of ‘designing and implementing appropriate procedures’ was the most important in supporting an inquiry-based science classroom. Understanding teachers’ views has implications for both the enactment of inquiry teaching in the classroom as well as the uptake of new teaching behaviors during professional development.

Preservice Elementary Teachers’ Images of Scientific Inquiry Regarding Practices of Next Generation Science Standards

Jeon, Kyungmoon,Biggers, Mandy S. 이화여자대학교 교과교육연구소 2017 교과교육학연구 Vol.21 No.4

We investigated Korean preservice elementary teachers’ mental images of science inquiry and inquiry teaching with respect to 8 specific Science and Engineering Practices (SEP). The preservice teachers had learned about science inquiry, but were not taught these SEP in their Korean curriculum. We asked them to draw and explain an imagined situation where they would be teaching science inquiry in an elementary science classroom. Some were also asked to describe an imagined situation of scientists conducting research. We applied the 8 SEPs as an analysis framework to review their images of science inquiry and inquiry teaching. The majority of students (93.2%) for elementary science teaching and all (100%) for science research represented images related to at least one SEP. However, students’ pictorial and/or written descriptions were restricted to some SEPs such as planning and carrying out investigations or analyzing and interpreting data. Although they tended to respond that asking questions and defining problems would be the most related to science inquiry among the 8 SEPs, they rarely applied those kinds of scenes to their drawings. Furthermore, using mathematics and computational thinking was hardly found in their ideas of elementary science inquiry teaching, and developing and using models was not represented as being part of scientists’ research. The findings indicate possible approaches to teachers’ professional development and suggest directions for further research.