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CIRCLE ACTIONS ON ORIENTED MANIFOLDS WITH FEW FIXED POINTS

  • Jang, Donghoon
    • East Asian mathematical journal
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    • v.36 no.5
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    • pp.593-604
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    • 2020
  • Let the circle act on a compact oriented manifold with a discrete fixed point set. At each fixed point, there are positive integers called weights, which describe the local action of S1 near the fixed point. In this paper, we provide the author's original proof that only uses the Atiyah-Singer index formula for the classification of the weights at the fixed points if the dimension of the manifold is 4 and there are at most 4 fixed points, which made the author possible to give a classification for any finite number of fixed points.

A CASE REPORT OF OSSIFYING FIBROMA OF THE MANDIBLE. (하악골에 발생한 골화성섬유종의 일례)

  • Lee You Dong
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.3 no.1
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    • pp.39-42
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    • 1973
  • The author has observed a case of ossifying fibroma occured in the left mandibular body area of 19 years old woman. In the serial roentgenograms, the author has drawn following conclusions: 1. The lesion is circumscribed and demarcated from the surrounding bone tissues. 2. The cortical bone of the involved area was expanded and thinned markedly on the site. 3. The radiopacity was increased with more or less mottled appearance on the site.

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Old/Rare Collection Development in University Libraries (대학도서관에서의 고서${\cdot}$귀중서 장서개발)

  • Yun Byeong-tae
    • Journal of the Korean Society for Library and Information Science
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    • v.9
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    • pp.3-35
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    • 1982
  • The author discusses about the collection development of old/rare collections in the university libraries. The method of this study is based upon the author's experiences at the University libraries and literature searching. Following items are discussed: (1) The characteristics and flow of old/rare books (2) Collection policies of old/rare books at the University libraries (3) Practical problems of the acquisition works concerning old/rare books (4) The conservation and weeding of old/rare book collection.

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Children′s Representations of Numbers

  • Park, Man-Goo
    • Research in Mathematical Education
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    • v.6 no.1
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    • pp.29-38
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    • 2002
  • The purpose of this paper was to examine early numerical representations between American and Korean children. Fifty-five first graders (35 Korean and 20 American) participated in the study. According to the findings of the current study, the author concluded that the Korean children had a stronger conception of base ten representations of numbers than that of the American children. The Korean children used various strategic reasoning such as decomposition and recomposition on the basis of base 10 structure to solve addition and subtraction problems effectively. However, the author cannot conclude that language differences would be the largest factor that would make Korean children sapient in the representations of base ten structures.

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A TWO-DIMENSIONAL FINITE VOLUME MODEL IN NONORTHOGONAL COORDINATE SYSTEM

  • Kim, Chang-Wan;Lee, Bong-Hee;Cho, Yong-Sik;Yoon, Tae-Hoon
    • Water Engineering Research
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    • v.2 no.3
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    • pp.151-160
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    • 2001
  • A two-dimensional flow model is newly developed. Two-dimensional shallow-water equations are discretized by the finite volume method. A nonorthogonal coordinate system is then employed. The developed model is applied to simulations of flows in a 180 degree curved bend flow. Numerical prediction are compared to available laboratory measurement. A good agreement is observed.

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Further Approximate Optimum Inspection Intervals

  • Leung, Kit-Nam Francis
    • Industrial Engineering and Management Systems
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    • v.4 no.2
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    • pp.123-128
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    • 2005
  • The author derives a general explicit formula and presents an heuristic algorithm for solving Baker’s model. The examples show that this new approximate solution procedure for determining near optimum inspection intervals is more accurate than the ones suggested by Chung (1993) and Vaurio (1994), and is more efficient computationally than the one suggested by Hariga (1996). The construction and solution of the simplest profit model for an exponential failure distribution were presented in Baker (1990), and approximate analytical results were obtained by Chung (1993) and Vaurio (1994). The author will therefore mainly devote the following discussion to the problem of further approximating optimum inspection intervals.

Proposal for the Promotion of Korean Neurosurgery

  • Choi, Joong-Uhn
    • Journal of Korean Neurosurgical Society
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    • v.43 no.1
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    • pp.1-4
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    • 2008
  • The author conducted a survey on the current status of neurosurgery around the world in preparation for Presidential Address at the International Society for Pediatric Neurosurgery (ISPN). The addresses and findings from the survey were presented at ISPN in 2006 and Child's Nervous System in 2007. After reviewing the current status of neurosurgery of various countries, the author would like to share this information with members of the Korean Neurosurgical Society, as well as offer a proposal to promote Korean neurosurgery around the world.

A STUDY OF DUPLICATING OCCLUSAL CONTOUR USING NEGATIVE INDEX (NEGATIVE INDES를 이용한 교합면 복제에 관한 연구)

  • Chang, Wan-Shik
    • The Journal of the Korean dental association
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    • v.19 no.2 s.141
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    • pp.159-162
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    • 1981
  • The author devised a simple technique for duplicating occlusal contour of natural teeth on the prepared abutments using hard stone index obtained from the study cast of natural teeth. Throughout this author devised method, the following advantages are studied. Firstly the dentist can obtain an ideal occlusal wax patterns which have arrived at the physiologic state through a long period of adjustment to various habits and functional movements. Secondly the construction procedure is simple, and thirdly it is easy to adjust wax pattern of nomal natural teeth which duplication is required.

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Chemical ecology in Insect Pest Mangement

  • Guan, Zhi-He
    • Korean journal of applied entomology
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    • v.31 no.3
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    • pp.276-288
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    • 1992
  • In this paper, the author gave a brief review on the meaning and background involving the growth of chemical ecology. Semichemicals which might be developed as insect control techniques incorporating in IPM program were described. The relevant semichemicals were grouped under separate topics including intraspecific semiochemicals, or pheromones (sex pheromones, alarm pheromones, and epidiectic pheromones), and interspecific semiochemicals, or allelochemics (allomones of Plant origin, and kairomones favoring natural enemies). Here, the author dealt with those of practical aspects only. The prospects of chemical ecology in insect pest management were also proposed.

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A Comparative Study of Mathematics Tests in China and UK

  • Bao Jiansheng
    • Research in Mathematical Education
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    • v.10 no.1 s.25
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    • pp.13-31
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    • 2006
  • This paper uses a composite difficulties model developed by the author (Bao 2002a, 2002b) to compare the characteristics of two sample mathematics tests in China and UK. The initial findings were described through five difficulty factors on several difficulty levels. According the initial findings, the author then tries to analyze the styles of mathematics problem-solving and the curriculum backgrounds in these two countries.

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