• 제목/요약/키워드: Physics-based

검색결과 2,764건 처리시간 0.044초

Threshold voltage control in dual gate ZnO-based thin film transistors

  • Park, Chan-Ho;Lee, Ki-Moon;Lee, Kwang-H.;Lee, Byoung-H.;Sung, Myung-M.;Im, Seong-Il
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
    • /
    • pp.527-530
    • /
    • 2009
  • We report on the fabrication of ZnO-based dual gate (DG) thin-film transistors (TFTs) with 20 nm-thick $Al_2O_3$ for both top and bottom dielectrics, which were deposited by atomic layer deposition on glass substrates at $200^{\circ}C$. Whether top or bottom gate is biased for sweep, our TFT almost symmetrically operates under a low voltage of 5 V showing a field mobility of ~0.4 $cm^2/V{\cdot}s$ along with the on/off ratio of $5{\times}10^4$. The threshold voltage of our DG TFT was systematically controlled from 0.5 to 2.0 V by varying counter gate input from +5 to -2 V.

  • PDF

Practical Suggestions for the Effective Use of Everyday Context in Teaching Physics -based on the analysis of students' learning processes-

  • Jeong, Hyun-Suk;Park, Jong-Won
    • 한국과학교육학회지
    • /
    • 제31권7호
    • /
    • pp.1025-1039
    • /
    • 2011
  • Even though many researchers have reported that everyday contexts can arouse students' interests and improve their science learning, the connection between everyday context and physics learning is not yet clearly discussed. In our study, at first, we assumed five guidelines for helping the development of teaching materials for physics learning in everyday context. Based on these guidelines, we developed teaching materials for understanding basic optics and applied these materials to ninth grade students. From the positive responses of students and science teachers about the developed materials, we could confirm that the guidelines were reflected well in the materials. And also, it was found that students and teachers wanted to learn or teach context-based physics in future classroom learning. However, all students do not receive benefits from learning physics in everyday context. By analyzing students' actual learning processes and interviews with them, we found five potential impeding factors which could hinder students' successful learning of physics in everyday context. As a result, we suggested five recommendations for overcoming these impeding factors.

High gain pentacene inverter using different pentacene-thickness in several dielectrics

  • Mun, Sung-Jin;Lee, Ki-Moon;Lee, Kwang-H.;Oh, Min-Suk;Im, Seong-Il
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
    • /
    • pp.826-829
    • /
    • 2009
  • The authors report on the fabrication of p-type depletion mode inverter that composed of two pentacene based thin-film transistors (TFTs) on several dielectric surfaces. We use shift of threshold voltage depends on pentacene-thickness.

  • PDF

Developing a Web-Based System for Testing Students' Physics Misconceptions (WEBSYSTEM) and its Implementation

  • Kim, Min-Kee;Choi, Jae-Hyeok;Song, Jin-Woong
    • 한국과학교육학회지
    • /
    • 제27권2호
    • /
    • pp.105-119
    • /
    • 2007
  • Several studies have attempted to test students' misconceptions of physics and to provide teaching strategies in order to repair them. The results from these studies have revealed that the diagnosis of students' misconception is crucial, although they often failed to grasp the practice of its implementation. In terms of being a type of methodology for science education, the Internet allows large-scale surveys and investigations to be carried out in a relatively short period of time. This paper reports the results of the development, implementation, and evaluation of a WEb-based SYStem for TEsting students' Misconceptions in physics (WEBSYSTEM) aimed at three groups (science educational researchers who study students' physics conceptions using the system as a detector, school science teachers who practice it as an instructional material, and students who benefit from it for their self-directed learning). The web-based testing system is based on a review of the instructional development strategies of ADDIE (Gustafson, Branch, 2002; Rha, Chung, 2001). Results showed that WEBSYSTEM could work effectively as a multi-purposed tool for the three target groups with a further partial revision, providing educational researchers with resourceful data to study students' misconceptions in physics. Issues of administrative strategies, reexamination of questionnaires, and international collaboration via WEBSYSTEM are discussed.

Synthesis of POSS Derived Organic-Inorganic Hybrid Esters for Insulating Oil Applications

  • Choi, Kyeong-Min;Harshavardhan, S.J.;Sridhar, Ch.;Vijaykumar, B.V.D.;Kumar, Deepak;Jang, Kiwan;Lee, Man-Sig;Shin, Dong-Soo
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권9호
    • /
    • pp.2769-2773
    • /
    • 2014
  • In this work, a new family of polyhedral oligomeric silsesquioxanes (POSS) based esters have been synthesized that consists eight ester functional groups. These are classified into Type-I and Type-II esters based on the starting materials, octakis(3-chloropropyl)silsesquioxane (Cl-POSS) and octakis(3-hydroxypropyldimethylsiloxy) octasilsesquioxane (OHPS) respectively. These new POSS type ester moieties can be used as insulating oils and oil additives in the transformers and also considered to be alternatives to mineral and vegetable oils that are presently used in the insulation system.