• 제목/요약/키워드: alternative school

검색결과 3,341건 처리시간 0.042초

Sulfur Tolerance Effects on Sr0.92Y0.08Ti0.5Fe0.5O3-δ as an Alternative Anode in Solid Oxide Fuel Cells

  • Kim, Jun Ho;Yun, Jeong Woo
    • Journal of Electrochemical Science and Technology
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    • 제9권2호
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    • pp.133-140
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    • 2018
  • $Sr_{0.92}Y_{0.08}Ti_{0.5}Fe_{0.5}O_{3-{\delta}}$ (SYTF0.5) is investigated as an alternative anode in $H_2$ fuels containing $H_2S$ (0-200 ppm). Although additional ionic conductivity is introduced by aliovalent substitution of $Ti^{4+}$ by $Fe^{3+}$ in the B-site, the SYTF0.5 has lower electrical conductivity than that of the $Sr_{0.92}Y_{0.08}TiO_{3-{\delta}}$. Due to the mixed ionic and electronic conductive (MIEC) property exhibited in the SYTF0.5 anode, the electrochemical performance of the SYTF0.5 anode is improved, as well as the sulfur tolerance. The maximum power densities in $H_2$ at $900^{\circ}C$ for the SYT anode and the SYTF0.5 anode were 56.9 and $98.6mW/cm^2$, respectively. The maximum power density in the SYTF0.5 anode at 200 ppm of $H_2S$ concentration decreased by only 12.9% (86.3 to $75.2mW/cm^2$).

로스팅 시간에 따른 녹두의 생리활성 변화 (Bioactivitiy Changes in Mung Beans according to the Roasting Time)

  • 송유빈;이경석;이명숙;김애정
    • 한국식품영양학회지
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    • 제26권3호
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    • pp.502-507
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    • 2013
  • This study was investigated the optimal time that enhanced the functional activities of mung beans for use of functional food resources. Mung beans were roasted according three levels of roasting time levels (10, 20 and 30 minutes) at $110^{\circ}C$ and then the physicochemical compositions were determined. The reducing sugar content was decreased with the increased roasting time. Moisture was decreased with increased roasting time, whereas, crude fat, crude ash, crude protein and carbohydrate were increased with prolonged roasting time. The highest contents of total phenol and flavonoid were shown at a roasting condition $110^{\circ}C$ for 30 minutes. The highest inhibitory activities of DPPH radical, ABTS radical and xanthine oxidase was the best at the condition of $110^{\circ}C$ for 30 min. From these results optimal roasting time of mung beans were 30 minutes for use of functional food resources.

판 구조론 학습에 사용되는 시각적 표상이 판구조론 개념에 대한 고등학생들의 응답에 미치는 영향 (The Effect of Visual Representation in Plate Tectonics Topics on High School Students' Conceptions on Plate Tectonics)

  • 이미숙;정진우;김형범
    • 대한지구과학교육학회지
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    • 제7권2호
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    • pp.214-225
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    • 2014
  • This study aimed to investigate the high school students' conceptions about the plate tectonics through visual representation. For this purpose, the subjects were 67 students in 11th-grade high schools in Chungbuk. In order to in-depth understand the students' conceptions about plate tectonics, so the investigator conducted a semi-structured interview. The conclusions were as in the following. After learning the plate tectonics, the students had the alternative conceptions associated with terminology, colors' meanings, plate-related melting, plate's movement, plates' boundaries, mantle's physical conditions, driving forces for plate movement, and they had the organic relations about colors' meanings, mantle's physical conditions, and driving forces of plate movement. Also, the visual representation used to teach plate tectonics influenced on the students' responses about terminology, plates' boundaries, plate-related melting and the mantle's physical features, also this study found the factors of visual representation causing the learners to create alternative conceptions. These results implicated the importance of teacher's role in identifying the students' interpretation process on visual representation, and it needed to improve the factors creating students' alternative conceptions about visual representation and to study the factors further.

Multivariate Analysis of Variance for Fuzzy Data

  • Kang, Man-Ki;Han, Sung-Il
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제4권1호
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    • pp.97-100
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    • 2004
  • We propose some properties of fuzzy multivariate analysis of variance by fuzzy vector operation with agreement index. We deals fuzzy null hypotheses and fuzzy alternative hypothesis and define the agreement index for the grades of the judgements that the hypothesis is rejection or acceptance. Finally, we provide an example to evaluate the judgements.

An Alternative Approach to the Robust Inventory Control Problem

  • Park, Kyungchul
    • Management Science and Financial Engineering
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    • 제20권2호
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    • pp.1-5
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    • 2014
  • The robust inventory control problem was proposed and solved by Bertsimas and Thiele (2006). Their results are very interesting in that the problem can be solved easily and also the solution possesses nice properties of those found in the traditional stochastic inventory control problem. However, their formulation is shown to be incorrect, which invalidates all of the results given there. In this paper, we propose an alternative formulation of the problem which uses a different but practically applicable uncertainty set. Under the newly proposed model, all of the useful properties given in Bertsimas and Thiele (2006) will be shown to be valid.

Existence and Stability Results on Nonlinear Delay Integro-Differential Equations with Random Impulses

  • Vinodkumar, Arumugam;Gowrisankar, Muthusamy;Mohankumar, Prathiban
    • Kyungpook Mathematical Journal
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    • 제56권2호
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    • pp.431-450
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    • 2016
  • In this paper, the existence, uniqueness, stability via continuous dependence and Ulam stabilities of nonlinear integro-differential equations with random impulses are studied under sufficient condition. The results are obtained by using Leray-Schauder alternative fixed point theorem and Banach contraction principle.

ON THE HYERS-ULAM SOLUTION AND STABILITY PROBLEM FOR GENERAL SET-VALUED EULER-LAGRANGE QUADRATIC FUNCTIONAL EQUATIONS

  • Dongwen, Zhang;John Michael, Rassias;Yongjin, Li
    • Korean Journal of Mathematics
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    • 제30권4호
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    • pp.571-592
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    • 2022
  • By established a Banach space with the Hausdorff distance, we introduce the alternative fixed-point theorem to explore the existence and uniqueness of a fixed subset of Y and investigate the stability of set-valued Euler-Lagrange functional equations in this space. Some properties of the Hausdorff distance are furthermore explored by a short and simple way.

대안학교의 생태중심주의 환경교육 실태 조사 (Survey on the Current Status of Ecocentric Environmental Education in Korean Alternative Schools)

  • 김영주;차정호;정철;이정호
    • 과학교육연구지
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    • 제34권2호
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    • pp.320-326
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    • 2010
  • 이 연구에서는 대안학교의 생태중심주의적인 환경 교육의 실태를 조사하였다. 전국 42개 대안학교의 홈페이지와 학교 안내책자를 통해 각 학교의 교육목표와 교육과정, 그리고 환경 활동을 조사하였다. 또한 추가적인 정보를 조사하기 위하여 대안학교 교사를 대상으로 면담도 실시하였다. 연구 결과 생태주의를 지향하는 학교의 비율은 상대적으로 낮았지만 42개 대안학교 중 36개교(85.7%)의 교육 목표에 생태주의를 직 간접적으로 포함하고 있었다. 39개교에서 환경 관련 교과를 편성하고 있었는데, 이 과목들은 평균적으로 주당 3시간씩 운영되었다. 대안학교에서 가장 빈번하게 사용되는 환경 활동은 분리수거였고, 다음으로는 일회용품 사용 줄이기와 친환경 및 재활용 용품 사용하기였다. 자체 정화조 사용하기와 대체 에너지 사용하기도 환경 활동으로 실천되고 있었다. 이에 대한 교육적 함의를 논의하였다.

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대구 지역 고등학생의 아침식사 이용실태 및 아침식사 대용식 인식조사 (Study on Breakfast Status and Perception of Substitution Foods for Breakfast in High School Students in Daegu Area)

  • 최재혁;박금순
    • 동아시아식생활학회지
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    • 제26권6호
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    • pp.565-574
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    • 2016
  • This study investigated eating behaviors of high school students (209 males and 230 females) in Daegu region by gender. As a result of analyzing breakfast intake frequency, 'Not rarely eat' showed the highest (25.1%), followed by '5 times a week' (24.4%), '2 times a week' (17.3%), '3 times a week' (15.0%), '1 time a week' (11.6%), and '4 times a week' (6.6%). Regarding reasons for skipping breakfast, 'lack of time' showed the highest percentages. For their breakfast, 53.5% of students ate boiled rice with side dishes. Regarding reasons for skipping breakfast, 'buy and eat snack' showed the highest percentages. Regarding favorite breakfast menu, 'rice roll, rice ball, rice burger' showed the highest percentage (55.4%), followed by 'bread & cereal' (28.7%) and 'fruits & vegetable' (7.7%). Regarding purchase of breakfast alternatives, 'Yes' was highest. Considering actors for choosing a breakfast alternative, there is a need for 'convenience of food consumption', 'spending less time', 'easy cooking', 'favorite menu' and 'taste' of the breakfast alternative. When asked how much they like breakfast alternative menus, they responded that they liked 'rice roll, rice ball, rice burger' (3.91), 'bread & cereal' (3.67), 'fruit & vegetable' (3.66), 'noodle' (3.39), 'porridge' (3.18) and 'rice cake' (3.07). This result shows that breakfast menus should be developed according to high school students preferences.