• Bulletin of the Korean Mathematical Society
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• v.52 no.2
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• pp.395-408
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• 2015

In present article, we determine the distinguishing number of the merged Johnson graphs which are generalization of both the Kneser graphs and the Johnson graphs.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.6
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• pp.869-879
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• 2023

Sparkle is one of the finalists in the Lightweight Cryptography Standardization Process conducted by NIST. It is a nonlinear permutation and serves as a core component for the authenticated encryption algorithm Schwaemm and the hash function Esch. In this paper, we provide specific forms of input and output differences for 6 rounds of Sparkle384 and 7 rounds of Sparkle512, and make formulas for the complexity of finding input pairs that satisfy these differentials. Due to the significantly lower complexity compared to similar tasks for random permutations with the same input and output sizes, they can be valid distinguishing attacks. The numbers(6 and 7) of attacked rounds are very close to the minimum numbers(7 and 8) of really used rounds.

• Journal of the Korean Society for Library and Information Science
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• v.28
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• pp.23-70
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• 1995

This study is to survey the present book numbers used in Korean libraries. to analyze their problems. and to suggest improvement in the book numbers. As the results of the survey several suggestions are derived as follows. 1. The education to the librarians about the kinds and the application methods of the book numbers used in Korean libraries should be sufficiently offered. 2. The present book numbers used should be expanded in detail for avoiding the duplication of the call numbers. Also when book numbers are assigned. shelf list cards should be examined one by one not to give the same number. If the book numbers are overlapped in the state not to expand further. libraries should establish a detailed expansion rules according to their respective situation and maintain it consistently. However, it is impossible for libraries operating open stack systems to arrange books on the shelves in call number sequence, therefore libraries can solve the problems as they accept duplication cases. 3. Since the object word of main mark IS a heading In main entry, we must apply cataloging rules to it closely. 4. For expanding book numbers widely it is desirable that the subsidiary mark of the book numbers which is the most prevalent in general and will be the most preferable In the future through the survey should be added and be provided. 5. The book numbers used being changed, we are to assign new book number leaving former materials as they are at the point of adopting a new book number. So aged materials are stored in a repository or on a compact shelf in the stack, will be discarded or weeded according to subjects after a certain period of time. 6. With library automation bringing together all the books of an author in a particular subject or in a particular form and avoiding completely duplication in open stack systems are meaningless. Rather than chronological book numbers, distinguishing clearly new materials from aged materials and controlling the stack spaces mechanically and effectively, can be regarded as the most modern and future-oriented of all the book numbers.

• Korean Journal of Acupuncture
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• v.26 no.4
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• pp.145-156
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• 2009

Objective : To increase the safety of moxibustion by understanding moxibustion-prohibited points' distinguishing features through literary inquiry. Method : We searched for moxibustion-prohibited points in Traditional Oriental Medical literature. Results : 1. Upon the advancement of moxibustion technique, the numbers of moxibustion-prohibited points increased. 2. Both Foot Meridians and Hand Meridians have similar percentage of moxibustion-prohibited points. Both Yin Meridians and Yang Meridians have similar percentage of moxibustion-prohibited points. 3. The face has the highest moxibustion-prohibited points ratio. The Back has the lowest moxibustion-prohibited points ratio. 4. We research 80 moxibustion-prohibited points and find 31 moxibustion-prohibitive reasons. A key reasons is that heating effect of moxibustion damages tissues, organs and meridian functions. There are also cases where the moxibustion-prohibited points can be designated upon the patients condition Conclusions : We could learn the distinguishing characteristics of moxibustion-prohibited points from this study. These results suggest that the treatment of moxibustion is more useful and safe.

• School Mathematics
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• v.12 no.3
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• pp.371-388
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• 2010

The goals of this study are to inquire middle school students' understanding about prime number and to propose pedagogical implications for school mathematics. Written questionnaire were given to 198 Korean seventh graders who had just finished learning about prime number and prime factorization and then 20 students participated in individual interviews for member checks. In defining prime and composite numbers, the students focused on distinguishing one from another by numbering of factors of agiven natural number. However, they hardly recognize the mathematical connection between prime and composite numbers related on the multiplicative structure of natural number. This study suggests that it is needed to emphasize the conceptual relationship between divisibility and prime decomposition and the prime numbers as the multiplicative building blocks of natural numbers based on the Fundamental Theorem of Arithmetic.

• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.399-415
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• 2017

Given a topological space X and a non-negative integer k, we study the self-homotopy equivalences of X that do not change maps from X to n-sphere $S^n$ homotopically by the composition for all $n{\geq}k$. We denote by ${\varepsilon}^{\sharp}_k(X)$ the set of all homotopy classes of such self-homotopy equivalences. This set is a dual concept of ${\varepsilon}^{\sharp}_k(X)$, which has been studied by several authors. We prove that if X is a finite CW complex, there are at most a finite number of distinguishing homotopy classes ${\varepsilon}^{\sharp}_k(X)$, whereas ${\varepsilon}^{\sharp}_k(X)$ may not be finite. Moreover, we obtain concrete computations of ${\varepsilon}^{\sharp}_k(X)$ to show that the cardinal of ${\varepsilon}^{\sharp}_k(X)$ is finite when X is either a Moore space or co-Moore space by using the self-closeness numbers.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.329-332
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• 2002

A theoretical study is made of the steady flow of a compressible fluid in a rapidly rotating finite cylinder. Flow is generated by imposing mechanical and/or thermal disturbances at the rotating endwall disks. Both the Ekman and Rossby numbers are small. A detailed consideration is given to the energy budget for a control volume in the Ekman boundary layer. A combination of physical variables, which is termed the energy contents, consisting of temperature and modified angular momentum, emerges to be relevant. The distinguishing features of a compressible fluid, in contrast to those of an incompressible fluid, are noted. For the Taylor-Proudman column to be sustained, in the interior, it is shown that the net energy transport between the solid disk wall and the interior fluid should vanish. Physical rationalizations are facilitated by resorting to the concept of the afore-stated energy content.

• Architectural research
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• v.22 no.4
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• pp.145-154
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• 2020

Zoning has long been criticized for its negative effects and has been taken for granted that zoning works as a hurdle to urban diversity. Responses in the US have emphasized more fine-grained zoning approaches that plan mixed use. This paper introduces and evaluates Seoul's zoning system as a possible alternative. While US zoning regulations have relied on distinguishing ever larger numbers of land use zoning categories, Seoul has opted to integrate new land uses into existing classifications, allowing for greater flexibility of use in each zone. Using municipal building records to evaluate land use in three mid-density residential districts, this paper demonstrates that Seoul's flexible zoning is capable of producing diverse mixed use neighborhoods. It then highlights the potential downside of this approach, showing that flexibility allows for the commercialization and sectoral gentrification of residential districts. It concludes by suggesting that a combination of flexible zones and more fine-grained plans would capture the advantages of both US and Korean planning.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.6-15
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• 2021

Various biometric and geometric measures were used to discriminate between the morphologically similar river puffer, Takifugu obscurus, tiger puffer, T. rubripes, their hybrids, and their triploid hybrids. The hybrids and triploid hybrids had greater anal fin width, nostril width, and snout length than the parental species (p<0.05). However, they had less caudal peduncle depth, inter-orbital width, head length, and head width(p<0.05). The morphometric and meristic characteristics of the hybrids and triploid hybrids were either intermediate between the parental species or more similar to those of one parental species. However, the external morphology of the hybrids and triploid hybrids was predominantly maternal. The triploid hybrids had asymmetry in the fin rays and gill raker numbers. This study identified phenotypic characteristics by distinguishing the morphological variables of river puffer, tiger puffer, their hybrids, and their triploid hybrids.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12A
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• pp.2019-2026
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• 2001

In this paper, we proposed the car license plate extraction and recognition algorithm using both the dynamical thresholding method and the kohonen algorithm. In general, the areas of car license plate in the car images have distinguishing characteristics, such as the differences in intensity between the areas of characters and the background of the plates, the fixed ratio of width to height of the plates, and the higher dynamical thresholded density rate 7han the other areas, etc. Taking advantage of the characteristics, the thresholded images were created from the original images, and also the density rates were computed. A candidate area was selected, whose density rate was corresponding to the properties of the car license plate obtained from the car license plate. The contour tracking method by utilizing the Kohonen algorithm was applied to extract the specific area which included characters and numbers from an extracted plate area. The characters and numbers of the license place were recognized by using Kohonen algorithm. Kohonen algorithm was very effective o? suppressing noises scattered around the contour. In this study, 80 car images were tested. The result indicate that we proposed is superior in performance.