• Title/Summary/Keyword: Main Classes

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Synthesis and Membrane Preparation of Polyimides for Non-aqueous System (비수계용 폴리이미드 합성 및 분리막 제조)

  • 전종영;탁태문
    • Proceedings of the Membrane Society of Korea Conference
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    • 1997.10a
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    • pp.39-45
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    • 1997
  • Introduction : Polyimides are one of the most important classes of the high performance polymers due to their excellent electrical, thermal, and high-temperature mechanical properties. But their uses are limited because of their poor solubility. Most polyimide derivatives are processed in the form of polyamic acids, which are subsequently converted into the imide structures.Recently, it has been found that the soluble polyimides with large molecular weight sufficient to application. For enhancing processability, the majority of approaches have involved the following factors. As much as, the separation of the imide ring along the back-bone, that is to say, reducing the density of imide ring in the repeat structure. The introduction of bulky substituents along the back-bone, in order to enhance the free volume of main-chain. The incorporation of flexible or thermally stable linkages in the main-chain, reducing the packing force. The disruption of symmetry or recurrence regularity through copolymerization in order to reduce crystallnity.The objectives of this investigation are the synthesis and characterization of soluble polyimides as membrane materials by the single-step polymerization and the preparation of the asymmetric polyimide membrane by using phase inversion technique. In the present study, three series of polyimide derivatives are synthesized; H series is homopolyimides, A series is prepared from single dianhydride and two diamines, B series is yielded from two dianhydrides and a diamine. The dope solution was directly prepared from the PI solution via one step polymerization from monomers.

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A Study on the Main Categories and Educational Influence of Chinese Ancient Humanism (중국 고대 인성론의 주요 범주와 교육적 영향)

  • JANG, Jong-Won
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.1
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    • pp.137-149
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    • 2016
  • Human development is the important role of education. There were thinkers of China emphasized the importance of education. These are divided into two general point of view. One theory is that as the representative of Mencius, Xuncius. Environment and education will be acquired this means that there is a crucial human development. $S{\grave{o}}ng$, $M{\acute{i}}ng$ dynasty came to the training began to do research for a decisive action. The other is to represent the viewpoint of Dongzhongshu, $H{\acute{a}}nyu$. According to their education was not to transcend the inherent limitations. Educator of ancient China have had a perspective that humanity can change. Humans show the progress theory emphasizes the potential of toughness as compared to the effect of the training point of view was divided into three classes emphasize the birth. Debate and the search for the humanity of the ancient educator had left us a valuable ideological material. Their perspective on a variety of personality is judged that there are many still take part in educational as well as the value of exploring far today.

On Using Films to Develop Students' Reading Skills in the MALL Classes

  • Sung, Tae-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.11
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    • pp.135-141
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    • 2017
  • Exposed to a great many media and technology resources, EFL students seem to lack the motivations for learning on the basis of the conventional teaching methods. For this reason, in teaching English, finding teaching methods and materials appropriate to make the learning experiences for EFL students more engaging and interesting has become more challenging than ever. This is the main reason why English language teachers always keep searching for more motivating teaching sources. Although most of course books have CD's and DVD enclosed, these turn out to be less authentic and not very engaging for students. In order to bring diversity into the classroom, many teachers use films in EFL teaching. Films are usually seen as a media that attracts students' attention and tend to present language in a more natural (interactive) way as well. What is more important is that films offer a visual context aids which help students understand and improve their reading skills. This paper analyzes the effects of using films in the EFL classroom. Moreover, It shows that films as a teaching resource play a very effective role in developing students reading and communication skill. Last but not least, mobile phones are used as a main supplementary device in that either group is recommended to watch a movie anytime and anywhere.

The "National Park Concept-Waste-Conservation" Model for the Environmental Education ("국립공원의 개념-훼손-보존" 모형의 환경교육적 접근)

  • 이민부;한주엽
    • Hwankyungkyoyuk
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    • v.8 no.1
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    • pp.151-165
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    • 1995
  • 1. This paper suggests one educational model of National Parks. The model includes main themes such as (1) concepts, (2) waste types, and (3) conservation policies of National Parks for the application at the school environmental education classes. 2. The study describes the origin of the national park system and concepts or policies for the conservation of the parks with cases of Japan, Taiwan, Canada, Australia, Swiss, Russia, and International Union for the Conservation of Nature and Natural Resources(IUCN). The main focuses of their concepts or policies are on the (1) public land, (2) conserved, (3) legally protected land, and (4) land for the education of the loving their country. 3. This research classifies wastes of parks as point, linear, areal, and cubic types, and explains wasting actions on each types, focused mainly on the mountainous national parks. 4. The suggested policies for the conserving national parks, in this paper, are (1) core-zoning policy, and (2) management policy within the core zone. 5. Some principles are suggested for the more effective realization of the policies: (1) enforcement, (2) abandonment,(3) restoration, (4) enlargement, (5) limitation, (6) incorporation, (7) monitoring, and (8) education. 6. Finally, the educational values of this model may be derived from concepts of (1) loving national land, (2) conservation of nature, (3) public responsibility for protection, and (4) education materials. Those concepts form the foundation of models for (1) civic education, (2) education of country, and (3) inquiry training.

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An Analysis of College Students' Satisfaction with Online Classes during COVID-19 Pandemic (COVID-19로 인한 전면 온라인 수업 전환과정에서 대학생의 수업만족도 변화 분석)

  • Kim, Min-Kyung;Jang, Yun-Jeong;Lee, Ji-Yeon
    • Journal of Information Technology Services
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    • v.20 no.6
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    • pp.125-139
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    • 2021
  • To explore college students' course satisfaction over the course of the semester during which a full-scale digital transformation was in progress due to COVID-19 pandemic, this study analyzed student survey data from a university located in the metropolitan area. To minimize the respondents' burden to answer long list of detailed questions in repetition, the study utilized a pulse survey method and students were asked to answer a brief and regular set of online questions 5 times throughout the semester. The number of survey respondents ranged from 1,640 to 4,116, with an average of more than 3,700. The main results and implications of this study are summarized as follows. First, the survey data indicated that the overall student satisfaction with online courses was above average (3.46/5). Vast majority of students have chosen pre-recorded, contents-based course over real-time, video-based course as their preferred course delivery method and this tendency remained the same throughout the semester. Second, the results of keyword network analysis of open-ended questions indicated that technical issues, increased workload (e.g., course assignments and course attendance) were main causes of online course dissatisfaction. And students suggested an unified online course platform and more interactive course design to further improve online courses in the future.

Application of IFC Standard in Interoperability and Energy Analysis

  • Hyunjoo Kim;Zhenhua Shen
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.87-93
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    • 2013
  • In this research, a new methodology to perform building energy analysis using Industry Foundation Classes (IFC) standard has been studied. With the help of Archicad 14 modeling software, a 3D test model is generated and then exported to IFCXML format. A ruby code program retrieves the building information from the resulting IFCXML file using Nokogiri library. An INP file is created and gets ready for next energy analysis step. DOE 2.2 program analyzes the INP file and gives a detailed report of the energy cost of the building. Case study shows when using the IFC standard method, the Interoperability of the energy analysis is greatly improved. The main stream 3D building modeling software supports IFC standard. DOE 2.2 is able to read the INP file generated by IFC file. This means almost any 3D model created by main stream modeling software can be analyze in terms of energy cost Thus, IFC based energy analysis method has a promising future. With the development and application of IFC standard, designers can do more complex and easy-to-run energy analysis in a more efficient way.

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Changes in Perceptions of Science Classes Using Artificial Intelligence among Elementary Teachers Participating in Research School (연구학교 참여 초등교사의 인공지능 활용 과학 수업에 관한 인식 변화)

  • Kim, Tae Ha;Yoon, Hye-Gyoung
    • Journal of Korean Elementary Science Education
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    • v.42 no.3
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    • pp.467-479
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    • 2023
  • For the successful implementation of education using artificial intelligence (AI) in schools, the perception of teachers is important. This study focuses on elementary school teachers and their perception of the need and teaching efficacy of science classes using AI before and after participating in a research school program. The analysis explores four key aspects, namely, learning, teaching, assessment, and communication. The study recruited 24 elementary school teachers from a school designated by the Gangwon Provincial Office of Education to participate in a year-long research school program. The study collected data using pre- and post-program surveys to explore changes in the perception of teachers regarding AI-based science classes. Furthermore, the researchers conducted individual in-depth interviews with four elementary school teachers to investigate the experience factors that influenced the changes in their perception of the aforementioned classes. The main findings were as follows. First, elementary school teachers were positively aware of the need for science classes using AI even prior to their research school experience; this perception remained positive after the research school program. Second, the science teaching efficacy of the elementary school teachers using AI was generally moderate. Even after the research school experience, the study found no statistically significant increase in efficacy in teaching science using AI. Third, by analyzing the necessity-efficacy as quadrants, the study observed that approximately half of the teachers who participated in the research school reported positive changes in learning, teaching, and assessment. Fourth, the study extracted four important experience factors that influenced the perception of the teachers of science classes using AI, namely, personal background and characteristics, personal class practice experience, teacher community activities, and administration and work of school. Furthermore, the study discussed the implications of these results in terms of the operation of research schools and science education using AI in elementary schools.

A Study on the Analytico-Synthetic Classification (분석적 합성식 문헌분류법에 관한 연구)

  • Oh Dong-Geun
    • Journal of the Korean Society for Library and Information Science
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    • v.32 no.2
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    • pp.55-76
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    • 1998
  • The first part of this article investigates the general characteristics and the advantages and disadvantages of the analytico-synthetic classification over the enumerative one. The second part analyzes the general steps and related problems in compiling an analytico-synthetic scheme, and investigates the steps further including facet analysis , choosing order in main classes, citation order and order in array : and adding notations, through an illustrative scheme for a matrimonial agency's records.

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Reconsidering of NCTM Standards (미국 스탠다드 수학의 재조명)

  • 김수미
    • Journal of Educational Research in Mathematics
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    • v.8 no.1
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    • pp.279-289
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    • 1998
  • Main stream of ’90s mathematics education in the U.S must be the NCTM Standards. Since it was published in 1989, much focus has put on it and numerous research has been tried to apply it to real mathematics classes. But there hasn't always good fame. Some schools have already mathematics. NCTM(1998), Standards and Principles for School Mathematics: Discussion Draft taken the curriculum based on it and recently the negative results have been exposed. Not a few parents, teachers and experts became to be worry about that. In this situation, I suppose it is worth to review the original purpose of Standards, look into the recent problems related to it's application and think of improvement or alternatives. This article mainly includes first two issues and particularily considers what problems are to have to be reconsidered in Korea. The following four are what I draw as problem: Basic operations; constructivism;texts and work books;trial and error strategy and group activity.

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ON SUMS OF CERTAIN CLASSES OF SERIES

  • Kim, Yong-Sup;Chaudhary, Mahendra Pal;Rathie, Arjun Kumar
    • Communications of the Korean Mathematical Society
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    • v.27 no.4
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    • pp.745-751
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    • 2012
  • The aim of this research note is to provide the sums of the series $$\sum_{k=0}^{\infty}(-1)^k\({{a-i}\atop{k}}\)\frac{1}{2^k(a+k+1)}$$ for $i$ = 0, ${\pm}1$,${\pm}2$,${\pm}3$,${\pm}4$,${\pm}5$. The results are obtained with the help of generalization of Bailey's summation theorem on the sum of a $_2F_1$ obtained earlier by Lavoie et al.. Several interesting results including those obtained earlier by Srivastava, Vowe and Seiffert, follow special cases of our main findings. The results derived in this research note are simple, interesting, easily established and (potentially) useful.