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An Analysis and Criticism on Subject Matter Related to Solid Figures in Korean Elementary School Mathematics Textbook (우리나라 초등학교 수학 교과서에서의 입체도형 관련 지도 내용에 대한 분석과 비판)

  • Kwon, Seok-Il;Park, Kyo-Sik
    • Journal of Educational Research in Mathematics
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    • v.21 no.3
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    • pp.221-237
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    • 2011
  • This paper focused on three drawbacks exposed in subject matter related to solid figures in elementary school math textbook. First, general solid figure are introduced before rectangular parallelepiped and cube in fifth grade math textbook, and prism and pyramid in sixth grade math textbook are introduced. Second, the process of abstraction from concrete objects to solid figures is insufficient in sixth grade math textbook. Third, some definitions in subject matter related to solid figures are inconsistent and ambiguous. The following four suggestions can be put forward as a conclusion based on these results. First, subject matter in textbooks must be correspond with that in curriculum. Second, it is necessary to inform teachers of range of subject matter through teachers guide book and manual for curriculum definitely. Third, each grade subject matter in math textbooks must be reexamined. Fourth, regular modification of math textbooks must be possible institutionally.

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An intelligent hybrid methodology of on-line system-level fault diagnosis for nuclear power plant

  • Peng, Min-jun;Wang, Hang;Chen, Shan-shan;Xia, Geng-lei;Liu, Yong-kuo;Yang, Xu;Ayodeji, Abiodun
    • Nuclear Engineering and Technology
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    • v.50 no.3
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    • pp.396-410
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    • 2018
  • To assist operators to properly assess the current situation of the plant, accurate fault diagnosis methodology should be available and used. A reliable fault diagnosis method is beneficial for the safety of nuclear power plants. The major idea proposed in this work is integrating the merits of different fault diagnosis methodologies to offset their obvious disadvantages and enhance the accuracy and credibility of on-line fault diagnosis. This methodology uses the principle component analysis-based model and multi-flow model to diagnose fault type. To ensure the accuracy of results from the multi-flow model, a mechanical simulation model is implemented to do the quantitative calculation. More significantly, mechanism simulation is implemented to provide training data with fault signatures. Furthermore, one of the distance formulas in similarity measurement-Mahalanobis distance-is applied for on-line failure degree evaluation. The performance of this methodology was evaluated by applying it to the reactor coolant system of a pressurized water reactor. The results of simulation analysis show the effectiveness and accuracy of this methodology, leading to better confidence of it being integrated as a part of the computerized operator support system to assist operators in decision-making.

Impact of Self-Citations on Impact Factor: A Study Across Disciplines, Countries and Continents

  • Pandita, Ramesh;Singh, Shivendra
    • Journal of Information Science Theory and Practice
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    • v.3 no.2
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    • pp.42-57
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    • 2015
  • Purpose. : The present study is an attempt to find out the impact of self-citations on Impact Factor (IF) across disciplines. The study examines the number of research articles published across 27 major subject fields covered by SCImago, encompassing as many as 310 sub-disciplines. The study evaluates aspects like percentage of self-citations across each discipline, leading self-citing countries and continents, and the impact of self-citation on their IF. Scope. : The study is global in nature, as it evaluates the trend of self-citation and its impact on IF of all the major subject disciplines of the world, along with countries and continents. IF has been calculated for the year 2012 by analyzing the articles published during the years 2010 and 2011. Methodology/Approach. : The study is empirical in nature; as such, statistical and mathematical tools and techniques have been employed to work out the distribution across disciplines. The evaluation has been purely under-taken on the secondary data, retrieved from SCImago Journal and Country Ranking. Findings. : Self-citations play a very significant part in inflating IF. All the subject fields under study are influenced by the practice of self-citation, ranging from 33.14% to 52.38%. Compared to the social sciences and the humanities, subject fields falling under the purview of pure and applied sciences have a higher number of self-citations, but a far lesser percentage than the social sciences and humanities. Upon excluding self-citations, a substantial amount of change was observed in the IF of subject fields under study, as 18 (66.66%) out of 27 subjects fields faced shuffle in their rankings. Variation in rankings based on IF with and without self-citation was observed at subject level, country level, and continental level.

Robust control of Electric Machine System Subject to Variable Load (가변 부하를 받는 전기 기계 시스템의 강인 제어)

  • Song, Jae-Bok
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.697-702
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    • 1997
  • Control system of electric machine systems is often required to provide the good control performance even in the presence of various variable loads. In this study, time delay control technique is adopted to overcome such variable loads. Also, in this research a new approach of avoiding saturation by varying the reference model for the time delay control based systems subject to the step changes in reference inputs. These schemes are verified by applications to the position controls of the AC servo motor system and the engine throttle actuator.

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Large-sample comparisons of calibration procedures when both measurements are subject to error

  • Lee, Seung-Hoon;Yum, Bong-Jin
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1990.04a
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    • pp.254-262
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    • 1990
  • A predictive functional relationship model is presented for the calibration problem in which the standard as well as the nonstandard measurements are subject to error. For the estimation of the relationship between the two measurements, the ordinary least squares and maximum likelihood estimation methods are considered, while for the prediction of unknown standard measurementswe consider direct and inverse approaches. Relative performances of those calibration procedures are compared in terms of the asymptotic mean square error of prediction.

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Free Vibration Analysis of Curved Beams in Cartesian Coordinates (직교좌표계에서 곡선보의 자유진동 해석)

  • BYOUNG KOO LEE
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.47-55
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    • 2003
  • Curved beams are one of the most important basic structural units as well as the beams, columns and plates. Most complicated structures consist of only these basic units and therefore it is very attractive research subject to analysis both the static and dynamic behavior of such units including the arches. The problems of free vibrations of curved beams have been the subject of much work due to their many practical applications.(an ellipsis)

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한국문헌정보학의 지식체계에 관한 연구- 문헌정보학관련 학회논문집 게재논문을 중심으로 -

  • 이수상
    • Journal of Korean Library and Information Science Society
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    • v.20
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    • pp.413-453
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    • 1993
  • This study aims at reviewing and analyzing the characteristics of library and information science in Korea by examming the research papers in two representative journals. In Korea, related scholarly associations have began about twenty years ago and produced a lot of research papers. For this work, I have established two aspects of knowledge system - cognitive object and subject. In this regards, the cognitive object menas the contents of research papers and the cognitive subject means the research methodology. In my opinion, this study obtains some characteristics of library and information science in Korea as follows: 1. There have been many research fields, but most of them have finished with just one or two results and not researched. 2. The adaption of information science to library science was hasty and had not the good effects in scholastic development. 3. Most research papers have been influenced by methodological prejudices. 4. In settling the native principles for the Korean phenomenon, there have been many problems. To solve these problems, I suggest that the existing research attitudes be converted to new one. I call this new research attitude 'everyday life centered research method'. Using this method, we can find the true basics and principles of library and information science in Korea.

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A Content Analysis of Articles in Journal of the Korean Society of Costume: 1977~2001 (한국복식학회지 [복식]에 게재된 논문의 내용분석 -창간호(1977)부터 51권 8호(2001)까지-)

  • 이미숙
    • Journal of the Korean Society of Costume
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    • v.52 no.4
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    • pp.97-109
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    • 2002
  • The purpose of this study was to examine volumes 1 through 51-8 of the Journal of the Korean Society of Costume in relation to past trends In content area of research reported, authorship, and funding source. Six subject matter areas were indentified: history of costume, apparel design and aesthetics, fashion marketing, social psychological aspects of clothing, clothing construction, textile science and etc. Of the 892 articles studies, history of costume research represented 40.1%(358). Studies which focused on apparel design and aesthetics increased in number as the journal matured. 51.8%(462) were authored by a sole individual. 48.2%(430) were authored by above two persons. Funding sources were indentified in 15.7%(140) of the 892 articles. College and university grants 72.9%(102) were acknowledged most frequently as a funding source.

Effect of Local Cosmetic Brand's Global Images on Domestic Consumers' Purchasing Decision

  • Han, Myung-Suk;Nam, Kyung-Hee
    • The International Journal of Costume Culture
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    • v.13 no.2
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    • pp.130-140
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    • 2010
  • This research was carried out by setting hypotheses on recognition of the global image of the research subject, a domestic cosmetic brand and consequent quality of the brand, reputation of the brand, purchasing decision, influence of images of expanded countries and their correlations to investigate what effect the global images of local brands practically have on domestic consumers' purchasing decision. The analysis results show that overseas expansion of the research subject brand has positive influence on the brand possessing global images. However, it can be seen that the quality of the brand has much larger influence on the reputation of the brand than the images of global brand. In addition, the images of the expanded countries have influence on purchasing decisions but the global images based on the expanded countries did not have much influence on purchasing decisions. Therefore, it can be seen that global images based on high levels of brand reputation and quality are requirements of a most competitive brand than images of the expanded countries in forecasting likelihood of purchase.

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Determinants of Growth of Public Technology Based Start-up: Focused on Subsequent Support of Technology Subject (공공기술 기반 창업기업 성장 결정요인: 기술주체의 후속지원을 중심으로)

  • Bong, Kang Ho
    • Knowledge Management Research
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    • v.21 no.2
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    • pp.41-58
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    • 2020
  • A plan to promote public technology-based start-ups as a way to enhance the use of public technology has been emphasized. However, the problem of creating commercial value has persisted due to the lack of reproducibility and readiness of public technology. Although gap exists in the linking process between the public and private sector, it is difficult to find objective empirical evidence as most of them are only qualitative research. Our empirical works examine the impact of subsequent support of the public research institute on the commercialization of public technologies. Then, we analyze how commercialization of public technologies affects the growth of technology-based startups using 2-stage least square (2SLS) model. We find that the linkage with the technology subject contribute to the successful commercialization of public technology, and further to the survival and growth of technology-based start-ups. Our finding suggests that knowledge management system, to facilitate interaction between technology developer and consumers, is needed for the success of public technology-based start-ups.