• 전기의세계
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• v.37 no.2
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• pp.28-42
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• 1988

본고에서는 실험변수(T,$o_{2}$/; over dot T)가 초전도 전이에 어떻게 영향을 끼치는가에 대하여 구조와 물성을 관련지우는 재료과학적 측면에서 살펴보고자 한다. 이를 위하여 우선 Y, Ba-Cu-O계에서 초전도체가 되기 위한 화학 조성 및 결정 구조상의 필요조건을 살펴보고, 주어진 양이온 조성 $Y_{1}$B $a_{2}$C $u_{3}$ $O_{x}$에 있어서 초전도 전이에 결정적인 역할을 하는 산소 음이온의 함량(x)조절에 대하여 열역학 및 동력학(kinetics)적 측면에서 논의한다. 본고의 내용은 1987년 11월말 현재까지 글쓴이가 얻을 수 있었던 지극히 제한된 수의 preprint, 또는 잡지에 발표된 논문과 10월 하순 하와이에서 개최된 제 172차 미국전기화학회에서 보고된 고온 초전도체에 관한 연구결과를 바탕으로 하였음을 밝혀둔다.

• Honam Mathematical Journal
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• v.36 no.3
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• pp.519-530
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• 2014

To study a deformation of a digital space from the viewpoint of digital homotopy theory, we have often used the notions of a weak k-deformation retract [20] and a strong k-deformation retract [10, 12, 13]. Thus the papers [10, 12, 13, 16] firstly developed the notion of a strong k-deformation retract which can play an important role in studying a homotopic thinning of a digital space. Besides, the paper [3] deals with a k-deformation retract and its homotopic property related to a digital fundamental group. Thus, as a survey article, comparing among a k-deformation retract in [3], a strong k-deformation retract in [10, 12, 13], a weak deformation k-retract in [20] and a digital k-homotopy equivalence [5, 24], we observe some relationships among them from the viewpoint of digital homotopy theory. Furthermore, the present paper deals with some parts of the preprint [10] which were not published in a journal (see Proposition 3.1). Finally, the present paper corrects Boxer's paper [3] as follows: even though the paper [3] referred to the notion of a digital homotopy equivalence (or a same k-homotopy type) which is a special kind of a k-deformation retract, we need to point out that the notion was already developed in [5] instead of [3] and further corrects the proof of Theorem 4.5 of Boxer's paper [3] (see the proof of Theorem 4.1 in the present paper). While the paper [4] refers some properties of a deck transformation group (or an automorphism group) of digital covering space without any citation, the study was early done by Han in his paper (see the paper [14]).

• Honam Mathematical Journal
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• v.36 no.3
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• pp.695-706
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• 2014

Various properties of digital covering spaces have been substantially used in studying digital homotopic properties of digital images. In particular, these are so related to the study of a digital fundamental group, a classification of digital images, an automorphism group of a digital covering space and so forth. The goal of the present paper, as a survey article, to speak out utility of digital covering theory. Besides, the present paper recalls that the papers [1, 4, 30] took their own approaches into the study of a digital fundamental group. For instance, they consider the digital fundamental group of the special digital image (X, 4), where X := $SC^{2,8}_4$ which is a simple closed 4-curve with eight elements in $Z^2$, as a group which is isomorphic to an infinite cyclic group such as (Z, +). In spite of this approach, they could not propose any digital topological tools to get the result. Namely, the papers [4, 30] consider a simple closed 4 or 8-curve to be a kind of simple closed curve from the viewpoint of a Hausdorff topological structure, i.e. a continuous analogue induced by an algebraic topological approach. However, in digital topology we need to develop a digital topological tool to calculate a digital fundamental group of a given digital space. Finally, the paper [9] firstly developed the notion of a digital covering space and further, the advanced and simplified version was proposed in [21]. Thus the present paper refers the history and the process of calculating a digital fundamental group by using various tools and some utilities of digital covering spaces. Furthermore, we deal with some parts of the preprint [11] which were not published in a journal (see Theorems 4.3 and 4.4). Finally, the paper suggests an efficient process of the calculation of digital fundamental groups of digital images.

• Journal of Korean Library and Information Science Society
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• v.6
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• pp.159-185
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• 1979

The dissemination of scientific information in Society involves interactions among a number of publics and many kinds of information channels. There is a need for examining the the entire process of information dissemination for the solving many problems which scientific many problems which scientific communication is now confronted with, This paper is an attempt to identify the functions of a scientific journal as one of major inf. transfer media, to clarify the problems in performing the functions, and to synthesize various on-going efforts toward the improvement and solution of such problems. Some conclusions derived from this study are as follows; (1) a scientific journal was, is and will be the valuable primary source for the recording and controlling scientific in formation which plays a role as a main energy source in the scientific activities. (2) Traditional built-in delays involved in the communication by a scientific journal should be improved by way of some new methods and techniques such as, of establishing a publishing center, controlling vocabularies in the scientific papers, distributing pre-publication materials, etc. (3) There should be a organized special committe for scientific communication for the assuming the responsibilities of educating, planning and carrying out activities relating to scientific information. (4) To improve the function of a scientific journal as information transfer media, other informal primary media such as report, preprint, etc, and secondary media such as abstracts and indexes should be studied which will result in the clarification of unigue functions, and advantages and disadvantages of each media. as an information dissemination media. (5) Each government should pay attention to the national information system as a changing social system and should recognize the gap in speed between technological development and the change of a social system Technological development should be made a contribution to the improvement of social system.

• Journal of Information Science Theory and Practice
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• v.6 no.4
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• pp.6-16
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• 2018

This article shows an approach to the study of two fundamental aspects of the prepublication of scientific manuscripts in specialized repositories (arXiv). The first refers to the size of the interaction of "standard papers" in journals appearing in the Web of Science (WoS)-now Clarivate Analytics-and "non-standard papers" (manuscripts appearing in arXiv). Specifically, we analyze the citations found in the WoS to articles in arXiv. The second aspect is how publication in arXiv affects the citation count of authors. The question is whether or not prepublishing in arXiv benefits authors from the point of view of increasing their citations, or rather produces a dispersion, which would diminish the relevance of their publications in evaluation processes. Data have been collected from arXiv, the websites of the journals, Google Scholar, and WoS following a specific ad hoc procedure. The number of citations in journal articles published in WoS to preprints in arXiv is not large. We show that citation counts from regular papers and preprints using different sources (arXiv, the journal's website, WoS) give completely different results. This suggests a rather scattered picture of citations that could distort the citation count of a given article against the author's interest. However, the number of WoS references to arXiv preprints is small, minimizing this potential negative effect.

• Journal of The Korean Astronomical Society
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• v.28 no.1
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• pp.31-43
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• 1995

We present UBVRI CCD photometry of the Type Ie supernova SN 19941 in M51 which was discovered on April 2, 1994 (UT). UBVRI CCD photometry of SN 1994 I were obtained for the period of the first two months from April 4, 1994, using the Seoul National University Observatory 60 cm telescope. The light curves of SN 19941 show several interesting features: (a) SN 19941 reaches the maximum brightness at B-band on April 8.23 (B = 13.68 mag), at V-band on April 9.10 (V = 12.89 mag), and at I-band on April 10.32 (I = 12.48 mag); (b) The light curves around the maximum brightness are much narrower than those of other types of supernovae; (c) The light curves after the peak decline more steeply than those of other types of supernovae; and (d) The colors get redder from $(V-R){\approx}0.2 mag ((V - I){\approx} 0.3 mag, (B - V){\approx}0.7 mag)$ on April 4 to $(V-R){\approx}0.6 mag ((V-1){\approx}0.9 mag, (B-V){\approx}1.3 mag)$ on April 18. Afterwards (V - R) colors get bluer slightly $(by\~0.005 mag/day)$, while (V-I) colors stay almost constant around $(V-1){\approx}1.0 mag$. The color at the maximum brightness is (B-V)=0.9 mag, which is $\~1$mag redder than the mean color of typical Type la supernovae at the maximum brightness. The light curves of SN 1994I are similar to those of the Type Ie supernova SN 1962L in NGC 1073. Adopting the distance modulus of $(m-M)_0 = 29.2 mag$ and the reddening of E(B - V) = 0.45 mag [Iwamoto et al. 1994, preprint for ApJ], we derive absolute magnitudes at the maximum brightness of SN 1994I, Mv(max) = -17.7 mag and MB(max) = -17.4 mag. This result shows that SN 1994I was $\~2$mag fainter at the maximum brightness compared with typical Type Ia supernovae. A narrower peak and faster decline after the maximum in the light curve of SN 1994I compared with other types of supernovae indicate that the progenitor of SN 1994I might be a lower mass star compared with those of other types of supernovae.