• 대한수학회보
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• 제59권3호
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• pp.617-642
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• 2022

For positive integers n and d with d < n, an n × n array A based on 𝒳 = {0, 1, …, nd} is called a sparse anti-magic square of order n with density d, denoted by SAMS(n, d), if each non-zero element of X occurs exactly once in A, and its row-sums, column-sums and two main diagonal-sums constitute a set of 2n + 2 consecutive integers. An SAMS(n, d) is called regular if there are exactly d non-zero elements in each row, each column and each main diagonal. In this paper, we investigate the existence of regular sparse anti-magic squares of order n ≡ 1, 5 (mod 6), and prove that there exists a regular SAMS(n, d) for any n ≥ 5, n ≡ 1, 5 (mod 6) and d with 2 ≤ d ≤ n - 1.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권1호
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• pp.21-29
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• 2011

Introduction: To compare the change in frontal ramal inclination (FRI) in laterognathism after orthognathic surgery. Materials and Methods: Twenty four patients (10 men, 14 women; mean age, $22.8{\pm}5.2$ years) with minimal facial canting (${\leq}$ 2 mm) and apparent menton deviation ($5.9{\pm}2.4\;mm$) who had been operated on to correct facial asymmetry and skeletal CIII malocclusion, were selected. On a preoperative posteroanterior (PA) cephalogram, the FRI of the deviated side and non deviated side, L1 deviation amounts and menton deviation amounts were measured. The FRI differences between both sides were compared, and the correlations between the measured deviated elements and the FRI differences were analyzed. On a postoperative PA cephalogram, the shifting amount of L1, shifting amount of L7 and FRI of both sides were measured, and the correlations between the shifting elements and the change in FRI were analyzed. Results: On the preoperative PA cephalogram, the FRI of the non deviated side was significantly greater than those of the deviated side. The differences in FRI, with a menton deviation amount showed a significant correlation. On the postoperative PA cephalogram, the FRI differences between the deviated and non deviated side were decreased significantly and mandibular transverse movement toward central position was noted. The mean shifting amounts of L7 were associated with the amount of change in the deviated side of FRI. Conclusion: Transverse shifting of the mandible through orthognathic surgery decreases the FRI difference, which showed laterognathism, and improves the facial contour.

• 대한치과교정학회지
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• 제24권2호
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• pp.479-508
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• 1994

This study was designed to investigate the reciprocal movement which was derived form application of active torque in ideal archwire by computer-aided three-dimensional finite element analysis of maxillary teeth and surrounding periodontal ligament composed of 2617 elements and 3725 nodes. Ideal archwire model was also made using the beam elements and the contact between the wire and the bracket slot was made using the gap element. In this study non-linear elastic behaviors of contact between the wire and the bracket slot were considered on. We put the active torque between the lateral and cenral incisor and between the second premolar and the first molar with/without cinch-back. The results were expressed by quantitative and visible ways. The findings of this study were as follows: 1. Reciprocal actions to active torque were complex system consisting of a combination of counter-torque, bucco-lingual linear displacement and tipping, rotation of the teeth, occluso-gingival linear displacement. 2. When active anterior crown labial torque was applied, crown labial tippings of the lateral were the greatest, and those of the central incisor was the next, Crown lingual tippings of the canine and the first premolar, mesial rotations and extrusion of the lateral and distal rotations and intrusion of the canine occurred. When anterior torque with the cinch-back was applied, amount of crown labial tippings of the lateral and central incisor were reduced. Amount of crown lingual tipping of the canine and the first premolar were increased. Mesial tippings and mesial rotations of the second molar occurred. 3. When active posterior crown lingual torque was applied, crown lingual tippings of the first moalr were the greatest, and crown labial tippings of the second premolar and the first premolar were the next, the crown lingual tipping of the second molar were a little. Mesial rotations of the second premolar occurred but those of the first premolar didn't occurred.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4803-4812
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• 2015

Chronic alcohol and tobacco abuse plays a crucial role in the development of different liver associated disorders. Intake promotes the generation of reactive oxygen species within hepatic cells exposing their DNA to continuous oxidative stress which finally leads to DNA damage. However in response to such damage an entangled protective repair machinery comprising different repair proteins like ATM, ATR, H2AX, MRN complex becomes activated. Under abnormal conditions the excessive reactive oxygen species generation results in genetic predisposition of various genes (as ADH, ALDH, CYP2E1, GSTT1, GSTP1 and GSTM1) involved in xenobiotic metabolic pathways, associated with susceptibility to different liver related diseases such as fibrosis, cirrhosis and hepatocellular carcinoma. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including hepatocellular carcinomas. The generated reactive oxygen species can also activate or repress epigenetic elements such as chromatin remodeling, non-coding RNAs (micro-RNAs), DNA (de) methylation and histone modification that affect gene expression, hence leading to various disorders. The present review provides comprehensive knowledge of different molecular mechanisms involved in gene polymorphism and their possible association with alcohol and tobacco consumption. The article also showcases the necessity of identifying novel diagnostic biomarkers for early cancer risk assessment among alcohol and tobacco users.

• 한국환경교육학회지:환경교육
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• 제18권2호
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• pp.90-100
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• 2005

This study was intended to investigate effects of building school forests on elementary school students, including changes in mental image of school, attitude toward nature and forest, and awareness of their relationship with school forest. The total number of 770 drawings and 1,124 writings were collected to be analyzed from three elementary schools. The results showed that there were significant differences between two student groups, respectively forest school group versus non-forest school group, in their mental image of school. For instance, more often observed in the drawings of forest school group students than their counterparts were natural and human elements, activities associated with nature, and natural or human elements located at central area. Also, more frequently found in the writings of forest school group students than their counterparts were letter-style sentences, stories about school forests, inherent values on nature and forest, and curiosity regarding the nature. These results seem to indicate that in order to materialize educational value of school forests, practical workshops for teachers need to be held as soon as possible and new activity models for students should be developed. In addition to that, long-term research on effectiveness of school forest have to be conducted to a number of schools.

• 대한수학회지
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• 제46권2호
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• pp.249-256
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• 2009

Let $G{\otimes}G$ be the tensor square of a group G. The set of all elements a in G such that $a{\otimes}g\;=\;1_{\otimes}$, for all g in G, is called the tensor centre of G and denoted by $Z^{\otimes}^$(G). In this paper some properties of the tensor centre of G are obtained and the capability of the pair of groups (G, G') is determined. Finally, the structure of $J_2$(G) will be described, where $J_2$(G) is the kernel of the map $\kappa$ : $G{\otimes}\;{\rightarrow}\;G'$.

• 복식
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• 제58권10호
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• pp.78-94
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• 2008

Contemporary fashion is experiencing a rise in design that combines heterogeneous things, or goes beyond the roles, boundaries, and meanings of existing things. This can be described as a 'heterogeneous fusion' that is different in character from the mixed use of heterogeneous materials, borrowed designs, and exaggeration of the silhouette that have been practices in fashion design, or the non-structure, deconstruction, and recombination that have existed since the age when post-structuralism was a central philosophy. This 'fusion' causes a 'confusion' of the generally accepted mental principle of 'one sense reacting to one stimulus', and breaks the boundary between the various senses, causing confusion in the senses of the individual, and leading him or her to experience unfamiliar feelings. In this process, all information received from external sources is not perceived as it is seen, but rather is perceived through a fusion of the individual's motivations, the environment in which it is perceived, the resulting change in emotion, and the individual's past memories. The combination of these heterogeneous elements visually accepted, or such a non-territorial combination acts as a 'fusion of senses' in the individual's perception, which causes confusion in the homeostasis of perception, and a change in emotion, and serves as a factor that causes the information to be stored in the memory for a long time. In parallel with deconstruction or non-structure, the 'heterogeneous fusion' found in modern fashion is taking root as a representative creative trend, and is represented in various forms such as the mixed use of subjects and materials, non-territorial borrowing, fusion with animal forms, fusion with non-physical geometry, and fusion with heterogeneous hair decoration.

• Structural Engineering and Mechanics
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• 제44권1호
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• pp.51-60
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• 2012

Concrete sleepers are essential components of the conventional railway. As support elements, sleepers are always subjective to a variety of time-dependent loads attributable to the train operations, either wheel or rail abnormalities. It has been observed that the sleepers may deteriorate due to these loads, inducing the formation of hairline cracks. There are two areas along the sleepers that are more prone to crack: the central and the rail seat sections. Several non-destructive methods have been developed to identify failures in structures. Health monitoring techniques are based on vibration responses measurements, which help engineers to identify the vibration-based damage or remotely monitor the sleeper health. In the present paper, the dynamic effects of the cracks in the vibration signatures of the railway pre-stressed concrete sleepers are investigated. The experimental modal analysis has been used to evaluate the modal bending changes in the vibration characteristics of the sleepers, differentiating between the central and the rail seat locations of the cracks. Modal parameters changes of the 'healthy' and cracked sleepers have been highlighted in terms of natural frequencies and modal damping. The paper concludes with a discussion of the most suitable failure indicator and it defines the vibration signatures of intact, central cracked and rail seat cracked sleepers.

• Structural Engineering and Mechanics
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• 제57권3호
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• pp.507-528
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• 2016

Reduced beam section (RBS) moment resisting connections are among the most economical and practical rigid steel connections developed in the aftermath of the 1994 Northridge and the 1995 Kobe earthquakes. Although the performance of RBS connection has been widely studied, this connection has not been subject to in the skewed conditions. In this study, the seismic performance of dogbone connection was investigated at different angles. The Commercial ABAQUS software was used to simulate the samples. The numerical results are first compared with experimental results to verify the accuracy. Nonlinear static analysis with von Mises yield criterion materials and the finite elements method were used to analyze the behavior of the samples The selected Hardening Strain of materials at cyclic loading and monotonic loading were kinematics and isotropic respectively The results show that in addition to reverse twisting of columns, change in beam angle relative to the central axis of the column has little impact on hysteresis response of samples. Any increase in the angle, leads to increased non-elastic resistance. As for Weak panel zone, with increase of the angle between the beam and the column, the initial submission will take place at a later time and at a larger rotation angle in the panel zone and this represents reduced amount of perpendicular force exerted on the column flange. In balanced and strong panel zones, with increase in the angle between the beam and the central axis of the column, the reduced beam section (RBS), reaches the failure limit faster and at a lower rotation angle. In connection of skewed beam, balanced panel zone, due to its good performance in disposition of plasticity process away from connection points and high energy absorption, is the best choice for panel zone. The ratio of maximum moment developed on the column was found to be within 0.84 to 1 plastic anchor point, which shows prevention of brittle fracture in connections.

• 한국콘텐츠학회논문지
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• 제11권2호
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• pp.79-87
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• 2011

현재 지문인식시스템 제품은 양적으로 빠른 성장세를 보이고 있으나 그 동안 질적인 품질을 고려하는 노력이 미흡한 것이 사실이었다. 따라서, 본 논문에서는 지식정보보안 제품의 질적인 면을 평가하여 품질 수준을 파악하여 개선방향을 도출함으로써 품질향상을 지원할 수 있는 평가모델을 개발하기 위해 지문인식시스템 제품의 국내외 시장현황과 기술적인 요소들을 분석하였다. 제품의 특성을 고려하여 보안성, 성능, 신뢰성 요구사항을 분석하여 기존 보안기능 중심의 평가에서는 다루지 못했던 비 기능 요소를 포괄적으로 적용할 수 있는 신뢰성 품질평가 모델을 구축하였다. 본 논문을 통해 지문인식 제품 특성과 동향을 반영하고 제품별 평가를 수행할 수 있는 신뢰성 평가모델을 구축함으로써 지식정보보안 제품의 전반적인 품질향상에 기여할 수 있을 것이다.