• 호남수학학술지
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• 제25권1호
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• pp.153-162
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• 2003

Recently, the generalized digital $(k_{0},\;k_{1})$-continuity and its properties are investigated. Furthermore, the k-type digital fundamental group for digital image has been studies with the generalized k-adjacencies. The main goal of this paper is to find some properties of the k-type digital fundamental group of Boxer and to investigate some properties of minimal simple closed k-curves with relation to their embedding into some spaces in ${\mathbb{Z}}^n(2{\leq}n{\leq}3)$.

• 호남수학학술지
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• 제30권4호
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• pp.589-602
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• 2008

As a survey-type article, the paper reviews various digital topological utilities from digital covering theory. Digital covering theory has strongly contributed to the calculation of the digital k-fundamental group of both a digital space(a set with k-adjacency or digital k-graph) and a digital product. Furthermore, it has been used in classifying digital spaces, establishing almost Van Kampen theory which is the digital version of van Kampen theorem in algebrate topology, developing the generalized universal covering property, and so forth. Finally, we remark on the digital k-surface structure of a Cartesian product of two simple closed $k_i$-curves in ${\mathbf{Z}}^n$, $i{\in}{1,2}$.

• 호남수학학술지
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• 제36권3호
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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]).

• Journal of Animal Science and Technology
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• 제46권3호
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• pp.415-426
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• 2004

소비자의 인구, 사회, 경제적 특성을 고려한 돈육 선호도 성향의 차이를 분석한 결과를 요약하면 다음과 같다. 먼저, 연령층에 따라 마블링을 제외한 육색, 지방두께 및 드립에 대한 선호도가 유의적으로 다르게 나타났다. 연령층이 18${\sim}$24세이면서 학생인 소비자들이 돈육 선호도 성향이 다른 연령층 및 직종의 소비자들과 비교하여 육색이 짙고 지방두께가 얇으면서 드립이 약간 있는 것을 선호하였고 연령이 증가할수록 육색이 연하면서 지방이 약간 있고 드립이 없는 돈육을 선호하였다(P < 0.05). 남성이 여성보다 육색이 약간 더 진하고 드립이 있는 돈육을 선호하는 것으로 나타났다(P < 0.05). 또한, 결혼유무에 따라 육색 및 드립에 대한 선호도 차이가 있었고, 직업의 종류에 따라 마블링을 제외한 육색, 지방두께 및 드립에 대한 선호도가 유의적으로 차이가 있는것으로 나타났다(P < 0.05). 한편, 소득수준에 따라서는 선호도에 차이가 없는 것으로 나타났다. 결론적으로 돈육 선택 시 소비자들은 연령, 성별, 결혼 상태 및 직업 종류에 따라 선호도 성향이 다르게 나타났으며, 이러한 결과를 활용하여 앞으로 한국 소비자들의 기호를 만족시킬 수 있는 돈육생산에 필요한 기초 자료로써 본 연구 결과가 이용될 수 있을 것으로 생각된다.