• Title/Summary/Keyword: High LET

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Web Contents Development of Virtual Geologic Field Survey for High School Students -Focusing on the Songaksan and Jisagae area of Jeju island- (고등학교 학생을 위한 가상지질조사 웹 컨텐츠 개발 -제주도 송악산과 지삿개를 중심으로-)

  • Hong, Seok-Eui;Lee, Chang-Zin
    • Journal of the Korean earth science society
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    • v.24 no.3
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    • pp.172-180
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    • 2003
  • Geologic field survey is very important for the high school students who take the courses of earth science under the 7th earth science curriculum, however actually it is very difficult for the students to survey in the field because of long time and distance, and expenses. To overcome these difficulties, this study focused on developing the web contents and teaching-learning materials for virtual geologic field survey of the Songaksan and Jisagae area, Jeju island. The developed web contents were placed into three parts; main manu, sub manu and contents to help the learners flow-chart of the program easily. To overcome the weakness of existing textual web materials, some movable images and worksheets were provided for the learners, and the web contents were designed for the learners to experience as similar as the geologic field survey may let them do.

Analysis for the Economic efficiency of District Heating and Gas Engine Co-generation System comparing with Central Heating System (중앙난방방식을 지역난방.소형열병합난방방식으로 전환시의 경제성 비교 분석)

  • Kim, Kyu-Saeng;Lee, Sang-Hyeok;Hong, Kyung-Pyo;Won, Young-Jae
    • Proceedings of the SAREK Conference
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    • 2007.11a
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    • pp.459-465
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    • 2007
  • This study was conducted to calculate the LCC of a apartment complex with a type of heating system, district heating and cogeneration system. For the purpose of analyzing LCC according to size of apartment complex, 500, 1,500 and 4,000 houses of model apartment selected. This research performs design of heating system and the life cycle cost analysis including an initial cost, energy cost, maintenance and operation cost, replacement cost and renovation cost during the project period(15years). According to the calculated results, 1) Initial cost of cogeneration system with 500, 1500 and 4000 houses is higher than district heating system each of 20%, 13%, 12%. 2) In case of cogeneration system, the payback period by electric generation is 5.21, 4.92 and 4.47 years and saving cost was calculated 29 billion won, 94 billion won and 262 billion won after payback period. 3) Cogeneration system LCC was 1.12, 1.07 and 1.06 times larger than district system with the size of apartment complex. According to the case of this study district heating system is more efficient than cogeneration system in terms of the reduction of LCC. 4) Gas Engine Co-generation System is more efficient than other systems because it can collect progressive part from electric charge progressive stage system. However, the efficiency is decreasing because of raising of fuel bills(LNG) and lowering of power rate for house use. Especially the engine is foreign-made so the cost of maintenance and repair is high and the technical expert is short. 5) District heating is also affected by fuel bills so we should improve energy efficiency through recovering of waste heat(incineration heat, etc.). Also, we should supply district cooling on the pattern of heat using of let the temperature high in winter and low in summer.

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A comparison study on characteristics of IPTV and digital CATV subscribers (IPTV가입자와 디지털 CATV가입자의 특성비교에 관한 연구)

  • Ryu, Gui-Yeol;Rhee, Eun-Jun;Lee, Hyun-Woo
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.4
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    • pp.665-675
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    • 2012
  • The object of study is to compare the characteristics of IPTV (Internet protocol television) subscribers and digital CATV (Community antenna television) subscribers. We used the adjusted residuals. We did gang survey for 100 subscribers in Seoul, Kyeonggi or Incheon regions. Compared to digital CATV, IPTV seems to have appropriate contents for interactive services and high satisfaction level for cost, but high dissatisfaction level for channels. Digital CATV subscribers would know and subscribe passively, compared to IPTV subscribers. IPTV subscribers are more satisfied than digital CATV subscribers even though IPTV is higher cost. Main content of digital CATV is sports, which is not interactive contents. People think IPTV is an innovative service which let subscribers see wanted contents always, but digital CATV is an extension of CATV. So digital CATV cannot use advantages of interactive services. Even though two services are almost same, they are very different in recognition.

Expanding Plan Study of KRTCS-2(Korean Radio Train Control System for Conventional & High Speed Railway) (일반 및 고속철도용 한국형열차제어시스템 확대적용 방안 연구)

  • Lee, Kang-Gyoo;Choi, Jong-gwoan;Sung, Dong-Il;Yun, Hak-Sun;Park, Jong-Won;Kim, You-Ho;Lee, Nam-Hyoung;Yoo, Jong-Cheon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.3
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    • pp.533-539
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    • 2017
  • ERTMS/ETCS Level 2 is currently planning, making contract, constructing and operating at several lines in European well-developed railway countries different from past ten years ago, and applying extensively for purpose of its intercompatibility and operational efficiency, and economic feasibility. On the other hand, ATP system correspond to ETCS Level 1, which was domestically introduced in early 2000, has introduced, operated, and planned or constructed in national railwaynetwork, but the lines, which its improvement period is come, are being occurred starting Gyeongbu Line. Therefore, we study the consideration and construction plan by stages if LTE-R Korean Radio-based Train Control System for conventional & high-speed railway under domestic development is extensively applied as the third National Railway Network Construction Plan was announced.

A case study on student's thoughts and expressions on various types of geometric series tasks (다양한 형태의 등비급수 과제들에 대한 학생들의 생각과 표현에 관한 사례연구)

  • Lee, Dong Gun
    • The Mathematical Education
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    • v.57 no.4
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    • pp.353-369
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    • 2018
  • This study started with the following questions. Suppose that students do not accept various forms of geometric series tasks as the same task. Also, let's say that the approach was different for each task. Then, when they realize that they are the same task, how will students connect the different approaches? This study is a process of pro-actively confirming whether or not such a question can be made. For this purpose, three students in the second grade of high school participated in the teaching experiment. The results of this study are as follows. It also confirmed how the students think about the various types of tasks in the geometric series. For example, students have stated that the value is 1 in a series type of task. However, in the case of the 0.999... type of task, the value is expressed as less than 1. At this time, we examined only mathematical expressions of students approaching each task. The problem of reachability was not encountered because the task represented by the series symbol approaches the problem solved by procedural calculation. However, in the 0.999... type of task, a variety of expressions were observed that revealed problems with reachability. The analysis of students' expressions related to geometric series can provide important information for infinite concepts and limit conceptual research. The problems of this study may be discussed through related studies. Perhaps more advanced research may be based on the results of this study. Through these discussions, I expect that the contents of infinity in the school field will not be forced unilaterally because there is no mathematical error, but it will be an opportunity for students to think about the learning method in a natural way.

The Nature of a Method Course for Prospective Secondary Mathematics Teachers

  • Kim, Seong-A;Lee, Sun Hee
    • Research in Mathematical Education
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    • v.23 no.4
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    • pp.235-254
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    • 2020
  • Through this study, we aimed to capture the nature of a mathematics method course, called "the Curriculum Development and Teaching Methods in Mathematics Education" which is a pedagogy course for teaching for secondary school mathematics taught at a university located in a south eastern part of South Korea. The research participants include three junior students who took the methods course and a local high school math teacher with two professors. The research has three parts. First, we designed a method course to prepare the junior or senior students for a teaching practicum. The individual students gave a mini lecture about a secondary mathematical topic as a course requirement. Second, the three students watched a classroom video-clip of the high school teacher and analyzed his instruction before the actual classroom visits. Furthermore, by "Let's Learn" program for students, the course was associated with a local community through the students and so that they could visit the teacher's classroom three times to observe his math classroom teaching. The students discussed the difference between their own mini lectures and the actual math classroom teaching to develop an understanding of what it entails to teach an actual math class. Third, the first author supervised the students' activities in the program including their report for it to bring out their findings to the class of the method course. We found out this method course provided the students with the experience of various aspects of actual math lesson as well as learning theories about the pedagogy for teaching for secondary school mathematics. We conclude that this course gives a model for the method course in mathematics education for secondary school mathematics.

The impact on the value perception of brand by experiential marketing to the attitude formation and behavioral intentions on active seniors - Comparing of the level of commitment - (액티브 시니어의 체험 마케팅을 통한 브랜드 가치지각이 태도 형성 및 행동 의도에 미치는 영향 - 몰입 정도에 따른 비교를 중심으로 -)

  • Lee, Sang In;Yu, Jihun
    • Journal of the Korea Fashion and Costume Design Association
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    • v.23 no.4
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    • pp.1-17
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    • 2021
  • This study was examined whether the experiential marketing factors proposed by Bernd Schmitt were applicable to the consumer behavior of active seniors. The study was analyzed the influence of SEMs have on value perception of brand and attitude formation as well as the behavioral intentions of active senior consumers and whether this effect differed between the level of commitment. For empirical analysis, frequency analysis, EFA, reliability, CFA, SEM, and multiple-group comparison analysis were performed. The results showed that sense and feel factor did not have a significant influence on the value perception of brand, while think factor had a positive effect on the value perception of brand. Act factor did not affect the value perception of brand; on the other hand, relate factor had a significant effect on the value perception of brand. The result of structural equation modeling also revealed that the value perception of brand had a positive influence on attitude formation and behavioral intentions. The result of multiple-group comparison analysis confirmed that the influence of act factor on value perception of brand differed according to the level of commitment, but the positive influence of act factor on value perception of brand was limited to the high-level of commitment group. As a result of the influence relate factor had on the value perception of brand, differences existed between the two groups, and the low-level of commitment group had a greater influence than the high-level of commitment group. So it will be effective for active senior consumers to form fashion communities and let them participate in to enhance positive consumer behavior toward fashion brands.

Characterization and Profiling of Liver microRNAs by RNA-sequencing in Cattle Divergently Selected for Residual Feed Intake

  • Al-Husseini, Wijdan;Chen, Yizhou;Gondro, Cedric;Herd, Robert M.;Gibson, John P.;Arthur, Paul F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.10
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    • pp.1371-1382
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    • 2016
  • MicroRNAs (miRNAs) are short non-coding RNAs that post-transcriptionally regulate expression of mRNAs in many biological pathways. Liver plays an important role in the feed efficiency of animals and high and low efficient cattle demonstrated different gene expression profiles by microarray. Here we report comprehensive miRNAs profiles by next-gen deep sequencing in Angus cattle divergently selected for residual feed intake (RFI) and identify miRNAs related to feed efficiency in beef cattle. Two microRNA libraries were constructed from pooled RNA extracted from livers of low and high RFI cattle, and sequenced by Illumina genome analyser. In total, 23,628,103 high quality short sequence reads were obtained and more than half of these reads were matched to the bovine genome (UMD 3.1). We identified 305 known bovine miRNAs. Bta-miR-143, bta-miR-30, bta-miR-122, bta-miR-378, and bta-let-7 were the top five most abundant miRNAs families expressed in liver, representing more than 63% of expressed miRNAs. We also identified 52 homologous miRNAs and 10 novel putative bovine-specific miRNAs, based on precursor sequence and the secondary structure and utilizing the miRBase (v. 21). We compared the miRNAs profile between high and low RFI animals and ranked the most differentially expressed bovine known miRNAs. Bovine miR-143 was the most abundant miRNA in the bovine liver and comprised 20% of total expressed mapped miRNAs. The most highly expressed miRNA in liver of mice and humans, miR-122, was the third most abundant in our cattle liver samples. We also identified 10 putative novel bovine-specific miRNA candidates. Differentially expressed miRNAs between high and low RFI cattle were identified with 18 miRNAs being up-regulated and 7 other miRNAs down-regulated in low RFI cattle. Our study has identified comprehensive miRNAs expressed in bovine liver. Some of the expressed miRNAs are novel in cattle. The differentially expressed miRNAs between high and low RFI give some insights into liver miRNAs regulating physiological pathways underlying variation in this measure of feed efficiency in bovines.

Moral Education & Environmental Ethics in High School (고등학교 도덕 교육과 환경 윤리)

  • Hwang, Kwang-oog
    • The Journal of Korean Philosophical History
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    • no.28
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    • pp.155-182
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    • 2010
  • When we divide Environmental Ethics education into the elements of 'knowledge - emotion - behavior', we need to focus on 'knowledge' at high school level. In general Moral Education, 'knowledge - emotion - behavior' is a circular link, but as Environmental Ethics is a matter of 'consciousness', it is desirable to instruct with the process of 'knowledge>emotion, behavior'. Teaching 'Consciousness on Nature' is not recommended at elementary or middle school level because it demands higher inference. On the contrary, considering the reality in high school it is not recommended to teach the necessity and method of recycling or to go field trip to the polluted area. Rather, it is better to inform the students of Environmental Ethics' viewpoints and let them know the ways of moral judgments. The view of nature in Orientalism is well explained through the Environmental Ethics' viewpoint. To explain the view of nature in Orientalism we should concentrate on the theory, not on the attitude of life. And we should rather compare the viewpoints of nature in Confucianism, Taoism and Buddhism respectively than explain in Orientalism all together. That is, if we compare with the viewpoints of Environmental Ethics and explain similarities & differences in Confucianism, Taoism and Buddhism, we can complement Environmental Ethics or present the third approach.

A Study on Wangtta and the effects of the Gurardian Angle Program among Adolescent Males. (수호천사 프로그램의 왕따 감소 효과에 관한 연구 -중학교 1학년 남학생 중심-)

  • 박경현;백경임
    • Journal of Korean Home Economics Education Association
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    • v.12 no.2
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    • pp.81-93
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    • 2000
  • This study is designed to identify the current condition of male students ostracized as the black ship (Wangtta in Korean) in middle schools and the effects of the Guardian Angle program on the decrease in Wangtta. 428 frist graders of two junior high schools were devided into two groups, a test group (n=195) and a control group (n=233). SPSS/PC+ program was used for analysis of the data, including frequency analysis, ANOVA and x(sup)2-test. The outcome of research can be summed up as the following 74.7% of the subjects thinks that there is Wangtta going on in there classes. Wangtta often comes to pass during the recesses (74.2%) and lunch times (51.6%). Those who are easily exposed to Wangtta are most likely to be both snobbish and pedantic. Those who lead Wangtta turn out to be good at fighting (56.4%) and dominant in the hegemony of the class depending on the way of ignoring or not playing with the victims(69.3%) In the case of bearing witness to Wangtta. 36.9% of the subjects try to overlook the case. Now let me take a look at the effect of the guardian angle program on the decrease in Wangtta. The program has a significant effect on the decrease (p<0.05) in the number and the phenomena of Wangtta perceived by students in both advance and post tests. The program makes a significant difference in the aspects of students’ behavior in relation to Wangtta in a desirable way (p<.01) Though the sociality index of the victims doesn’t show any significant difference statistically, it exerts a generally positive effect.

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