• Title/Summary/Keyword: Research Field

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Carbon nanotube / silane hybride film for highly efficient field emitter

  • Jeong, Hae-Deuk;Kim, Ho-Young;Jeong, Hee-Jin;Han, Joong-Tark;Lee, Geon-Woong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.181-181
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    • 2010
  • Few-walled carbon nanotubes (FWNTs)-based field emitters with long term stability are fabricated by using a spray method. Tetraethylorthosilicate (TEOS) sol as a binder was mixed with dispersed solution of FWNTs to enhance the adhesion of FWNTs on the cathode substrate. Due to the strong intermolecular interaction of TEOS to the functional groups attached on CNTs and substrate, CNTs are tightly adhered to the cathode electrode when heat treatment is performed at $150^{\circ}C$ for 1 hour, resulting in a stable electron emission of CNT emitters for long time. Excellent field emission characteristics were exhibited, with a large field enhancement factor and low turn-on voltage, comparable to those of CNT emitters fabricated by a screen printing of CNT paste. Therefore, FWNTs / TEOS hybrid films could be utilized as an alternative for the efficient and reliable field emitters.

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A Critical Review of the Research on Learning during Field-trips

  • Choi, Mee-Young
    • Journal of The Korean Association For Science Education
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    • v.25 no.1
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    • pp.57-77
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    • 2005
  • This review is aimed at the understanding of learning in field-trips relating to education in outdoor activities. The review specifically concerns what studies have been undertaken by seeking evidence from research published between 1950 and 2004. The review indicates three common arguments on learning during field-trips. First, the learning in an informal learning environment based on first-hand experiences is most significant when it has meaning for the learner from field-trips. Second, learning aims and strategies in field-trips have evolved along with world-wide concerns towards the environment. Third, the experiences from field-trips can impact significantly on students' cognitive and affective learning. However, the research of field-trip experiences from outdoor activities has focused on learning outcomes far more than on the learning characteristics which facilitate students' learning. Therefore, further study is required, which can provide clear evidence on how such learning characteristics through field-trips can help studentsto successfully attain educational goals.

A Study on Metadata Development for Establishing International Research Cooperation Information Database (국제연구협력정보 DB 구축을 위한 메타데이터 개발에 관한 연구)

  • Noh, Younghee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.29 no.2
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    • pp.5-34
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    • 2018
  • In this research, we intended to discover all types of information related to international research cooperation, collect information by each type, and build a database. To this end, we initially developed metadata, discussed with metadata experts to develop metadata in the primary phase, and conducted a survey on the experts related to international research cooperation. Furthermore, we collected and entered data in the meta field for each type of information source, and verified the meta field through processes such as the existence of actual data for each meta field, among others. The types of database designed in this research are the international research cooperation information source database, international research cooperation project database, international research cooperation expert database, international research cooperation institution database, international organization database, and other database, and as a result of validating of the field by entering the data by conducting the survey, the survey results and the data entry rate by field demonstrated such a high rate of consistency. However, only the international organization data field was confirmed to have approximately 25% of the field having the data entry rate of less than 10% despite the high rate of significance rated by the users.

A Study on Design Standard for Paddy Field Ramp (수도 포장진입로의 설계기준에 관한 연구)

  • 김병갑;이중용;신승엽;김학주;이용복
    • Journal of Biosystems Engineering
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    • v.26 no.6
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    • pp.517-524
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    • 2001
  • Steep and narrow ramp installed in the paddy field makes it difficult and sometimes dangerous to drive agricultural machines on it. Because agricultural machinery become larger and heavier, it is necessary to revise design standard for ramp to provide safe travel. This study was conducted to revise the design standard fur paddy field ramp, especially for its width and slope. A mathematical model predicting travelling path of a tractor on paddy field ramp and farm road was developed and simulated. To verify this model, field tests were carried out. The model could predict trvelling path with RMS Error of 12.5cm and 8.2cm, which were judged to be adoptable fur determining the width of paddy field ramp. By applying this model to 110ps tractor, which was assumed to be the largest tractor in Korea, width of paddy field ramp was determined as over 3.6m. The slope of paddy field ramp, which provided tractor with 10% of the total weight of the tractor and the mounted implement as reaction force at front wheel against ground was analyzed by considering weight transfer effect on a ramp. The result showed that adequate slope of paddy field ramp was 14°.

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A Study on Oxygen Diffusion Characteristics According to Changes in Flow Field Shape of Polymer Electrolyte Membrane Fuel Cell Metallic Bipolar Plate for Building (건물용 고분자 전해질 연료전지 금속분리판 유동장 형상 변화에 따른 산소 확산 특성에 대한 연구)

  • PARK, DONGHWAN;SOHN, YOUNG-JUN;CHOI, YOON-YOUNG;KIM, MINJIN;HONG, JONGSUP
    • Journal of Hydrogen and New Energy
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    • v.32 no.4
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    • pp.245-255
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    • 2021
  • Various studies about metallic bipolar plates have been conducted to improve fuel cell performance through flow field design optimization. These research works have been mainly focused on fuel cells for vehicle, but not fuel cells for building. In order to reduce the price and volume of fuel cell stacks for building, it is necessary to apply a metallic flow field, In this study, for a metallic flow field applied to a fuel cell for building, the effect of a change in the flow field shape on the performance of a polymer electrolyte membrane fuel cell was confirmed using a model and experiments with a down-sizing single cell. As a result, the flow field using a metal foam outperforms the channel type flow field because it has higher internal differential pressure and higher reactants velocity in gas diffusion layer, resulting in higher water removal and higher oxygen concentration in the catalyst layer than the channel type flow field. This study is expected to contribute to providing basic data for selecting the optimal flow field for the full stack of polymer electrolyte membrane fuel cells for buildings.

Research Ethics in the Aviation Service Industry

  • Soyeon PARK
    • Journal of Research and Publication Ethics
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    • v.5 no.1
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    • pp.7-11
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    • 2024
  • Purpose: This study seeks to discuss research ethics, not only the academic honesty and sincerity that researchers who study aviation services academically should have, but also the direction of the moral aspects that are fundamentally required as researchers. Additionally, this study seeks to examine the realistic problems of research related to the aviation service industry, a field of social science. Lastly, focusing on research ethics in the aviation service field, we will look at the theoretical background and the problems in the actual research field, and draw implications based on this. Research design, data and methodology: This study conducted an exploratory study through a selection process based on research ethics topics and research ethics related to the aviation service industry. Results: Efforts to systematize research ethics in research areas related to the aviation service industry, which is a field of social science, require efforts to expand the scope of systematization of research ethics related to the aviation service industry by referring to systemization efforts in other academic fields. In addition, specific systemization efforts will be needed through cooperation between universities, research institutes, and academic organizations. Also, concrete systematization efforts will be needed through cooperation between universities and academic organizations.

A Study on the Metadata based on the Semantic Structure of the Humanities Research Articles for Research Data (인문학 분야 연구데이터를 위한 연구논문의 의미구조 기반 메타데이터 연구)

  • An, Byoung-Goon;Ko, Young Man
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.33 no.1
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    • pp.345-369
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    • 2022
  • The purpose of this study is to build a metadata set based on the semantic structure of the humanities field research articles for research data that can associate research data and research articles. To understand the interest of Humanities researchers, keywords of research articles were categorized. By proceeding the keywords classification and analyzing based on the semantic structure of general research papers, additional elements to be added were identified for reflecting the characteristics of the humanities field. Based on it, 17 metadata elements based on the semantic structure of research papers in the humanities field was determined. In order to evaluate whether the metadata is appropriate as a metadata for research data in the humanities field, a survey was conducted on researchers in the humanities field. As a result of the survey, 7 elements were judged to be suitable for use as metadata for research data in the field of humanities, and 10 other elements were identified as usable elements. Drawing on the survey results, the metadata based on the semantic structure of the humanities field research articles for research data was constructed.

Measurement of Variability of Chlorophyll Contents in Paddy Fields Using Two Kinds of Chlorophyll Meter (2종의 엽록소 측정기를 이용한 포장내 벼의 엽록소 함량 분포 측정)

  • 성제훈;서상룡;박우풍;정인규;김상철;이충근
    • Journal of Biosystems Engineering
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    • v.28 no.3
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    • pp.245-252
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    • 2003
  • This study was investigated the possibility of measuring chlorophyll in paddy crops using two kinds of chlorophyll meters(SPAD-502, Field Scout). The results of correlation analysis showed the 0.7758(r$^2$) relationship between the chlorophyll contents of paddy leaves measured by SPAD and spectrophotometer. It indicates that chlorophyll content in paddy crops could be measured using the SPAD. Considering the data of the SPAD and Field Scout there was significant difference between their chlorophyll contents measured by the SPAD and Field Scout. Likewise, such results were consistent with the corrected data using light intensity. According to the results, it can be concluded that it is difficult to describe the rice chlorophyll measured by the Field Scout more accurately than the SPAD when using one standard spectrum and another spectrum for reflectance measuring. The chlorophyll variance measured at a research institute and a farmer's field revealed that the output of SPAD was more reliable than that of the Field Scout.

System Requirement Review of Lunar Surface magnetometer on the CLPS program

  • Jin, Ho;Kim, Khan-Hyuk;Lee, Seongwhan;Lee, Hyojeong;Seon, Daerac;Jung, Byungwook;Jang, Yunho;Park, Hyeonhu
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.40.1-40.1
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    • 2020
  • The Korea Astronomy and Space Science Institute is participating as a South Korean partner in the Commercial Lunar Payload Services (CLPS)of NASA. In response, the Korea Astronomy and Space Science Institute is currently conducting basic research for the development of four candidate instrument payloads. The magnetic field instrument is one of them and it's scientific mission objective is the moon's surface magnetic field investigation. Therefore, the development requirement of the lunar surface magnetic field instrument were derived and the initial conceptual design was started. The magnetic field instrument has a 1.2 meter boom which has two three-axis fluxgate magnetometer sensors and one gyro sensor to get a attitude information of the boom. The concept of measuring the lunar surface magnetic field will carry out using multiple sensors by placing semiconductor type magnetic field sensors inside the electric box including boom mounted fluxgate sensors. In order to overcome the very short development period, we will use the KPLO (Korean Lunar Pathfinder Orbiter) magnetometer design and parts to improve reliabilities for this instrument. In this presentation, we introduce the instrument requirements and conceptual design for the Lunar surface magnetic field instruments.

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Antenna Measurement on Cylindrical Surface in Fresnel Region Using Direct Far-Field Measurement System

  • Oh, Soon-Soo;Kim, Joung-Myoun;Yun, Jae-Hoon
    • ETRI Journal
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    • v.29 no.2
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    • pp.135-142
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    • 2007
  • The small anechoic chambers built by many small-/medium-sized companies and universities present difficulties in testing electrically large antennas because the chamber size cannot satisfy the far-field criterion of large antennas. In this paper, a method for Fresnel-region measurement on a cylindrical surface with variation of the measurement height is proposed and verified by both calculations and experiments. We implement the proposed method using a direct far-field measurement system by adding a few supporting structures. The results show good accuracy.

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