• Asian-Australasian Journal of Animal Sciences
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• 제2권3호
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• pp.329-330
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• 1989

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.449-449
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• 2011

We reported the direct effect of intrinsic surface energy of dry adhesive material to the Van der Waals and capillary forces contributions of the total adhesion force in an artificial gecko-inspired adhesion system. To mimic the gecko foot we fabricated tilted nanohairy structures using both lithography and ion beam treatment. The nanohairy structures were replicated from Si wafer mold using UV curable polymeric materials. The control of nanohairs slanting angles was based on the uniform linear argon ion irradiation to the nanohairy polymeric surface. The surface energy was studied utilizing subsequent conventional oxygen ion treatment on the nanohairy structures which resulted in gradient surface energy. Our shear adhesion test results were found in good agreement with the accepted Van der Waals and capillary forces theory in the gecko adhesion system. Surface energy would give a direct impact to the effective Hamaker constant in Van der Waals force and the filling angle (${\varphi}$) of water meniscus in capillary force contributions of gecko inspired adhesion system. With the increasing surface energy, the effective Hamaker constant also increased but the filling angle decreased, resulting in a competition between the two forces. Using a simple mathematical model, we compared our experimental results to show the quantitative contributions of Van der Waals and capillary forces in a single adhesion system on both hydrophobic and hydrophilic surfaces. We found that the Van der Waals force contributes about 82.75% and 89.97% to the total adhesion force on hydrophilic and hydrophobic test surfaces, respectively, while the remaining contribution was occupied by capillary force. We also showed that it is possible to design ultrahigh dry adhesive with adhesion strength of more than 10 times higher than apparent gecko adhesion force by controlling the surface energy and the slanting angle induced-contact line of dry adhesive the materials.

• 접착 및 계면
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• 제24권1호
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• pp.36-40
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• 2023

반데르발스 물질이란 층간 결합이 약한 반데르발스 결합으로 이루어진 이차원 층상구조를 지닌 물질을 의미하며, 이러한 반데르발스 이차원 소재를 이용한 이종접합 구조 연구는 그래핀이 발견된 이후 꾸준히 연구되고 있다. 본 논문에서는 대기압 화학기상증착법을 통해 성장된 단층 단결정 MoSe₂를 기반으로하는 반데르발스 이종접합 트랜지스터 소자에 대해 보고한다. 최적화된 공정조건에서 성장된 MoSe₂는 원자수준의 결함이 존재하지 않는 것을 밝혔으며, 이를 이용한 트랜지스터 소자 또한 우수한 특성을 보인다는 것을 밝혀내었다.

• Architectural research
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• 제12권1호
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• pp.33-38
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• 2010

Many theorists acknowledge that Modern architecture denied the architect's crafty gesture for the sake of pure formal and compositional status of a building. As well, modern technology in construction has been prevailing as the sole support for modern architecture. But there exists architects who proposed a dialectic development of traditional and modern techniques. This thought was prominent in Germanic circle where technological development was in advance. Throughout $20^{th}$ century, the works of Adolf Loos, Mies Van der Rohe, and Peter Zumthor are representatives in each period. A common point begins from their apprenticeships as craftsmen: Loos and Mies as stonemasons, Zumthor as a cabinetmaker. More than this fact, their craftsmanship is embedded in their works and express creativity of architects. While mass production system raises non-participatory practice that merely require assemblage of products, the adjusted techniques with craftsmanship brings forth a participatory practice that does not limit the creativity of architects.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.603-605
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• 2003

Constructing a geo-spatial database of Graphic Information Systems(GIS) in various applications is suffering from the difficulty of data acquisition, which is labor-intensive and time consuming. In order to provide the spatial data rapidly and accurately, 4S-Van, a prototype mobile mapping system, has been developed. This paper presents a novel approach for an analysis for Mobile Mapping Systems. Furthermore, we discuss the accuracy of measurements using images acquired from the 4S-Van. The first part of this paper introduces accuracies of other mobile mapping systems. Then, we describe main features of the 4S-Van and our proposed method for an analysis accuracies, which can be applicable to other mobile mapping systems. The last part of paper concludes with a summary and our suggestions for implementation of mobile mapping system.

• Archives of Plastic Surgery
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• 제49권1호
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• pp.55-58
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• 2022

In Van der Woude syndrome (VWS), a rare congenital disease, lower lip pits (LLPs) can cause an aesthetically significant deformity. Surgical treatment of LLPs is necessary if they cause recurrent inflammation or aesthetic problems. Intraoperatively, surgeons should keep in mind the possibility of deep extension of the sinus tract and the relative deficiency of the midline in VWS, which increases the risk of lip disfigurement. Herein, we emphasize the importance of using a tissue-preserving technique to improve aesthetic results in VWS patients with a sinus tract.

• 대한수학교육학회지:수학교육학연구
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• 제8권1호
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• pp.291-298
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• 1998

This study deals with the problem of proof education in the middle school geometry bby examining van Hiele#s geometric thought level theory and Freudenthal#s mathematization teaching theory. The implications that have been revealed by examining the theory of van Hie이 and Freudenthal are as follows. First of all, the proof education at present that follows the order of #definition-theorem-proof#should be reconsidered. This order of proof-teaching may have the danger that fix the proof education poorly and formally by imposing the ready-made mathematics as the mere record of proof on students rather than suggesting the proof as the real thought activity. Hence we should encourage students in reinventing #proving#as the means of organization and mathematization. Second, proof-learning can not start by introducing the term of proof only. We should recognize proof-learning as a gradual process which forms with understanding the meaning of proof on the basic of the various activities, such as observation of geometric figures, analysis of the properties of geometric figures and construction of the relationship among those properties. Moreover students should be given this natural ground of proof.

• 복식
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• 제63권5호
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• pp.115-131
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• 2013

Dries Van Noten, one of the Antwerp Six, focused on recreating traditional attire from each region to complex contemporary attire and has shown designs that interpreted ethnic image in contemporary perspective from his very first collection. He has positioned himself as a designer with creative expression of ethnic image through broad use of various patterns. This paper analyze the use of pattern in Dries Van Noten's designs by season and item, and reflects on the characteristics of pattern use and influence on fashion image. Total of 887 clothing items were collected from Noten's collections on the Internet. Through analysis of frequency and percentage and cross tab of expression techniques, types, patterns of each motif, and classifications of print combinations, it was shown that Noten has applied six aesthetic rules in the use of pattern design. Pattern played the most significant role in his design. It was possible to achieve the balance of ethnic image and modern image with the mix of flower and abstract motives. Overall pattern was mostly used for practical purpose: border patterns and spaced patterns played a vital role in rendering uniqueness. Noten exhibited unity and variation in combining prints. He expressed the beauty of Oriental style by inserting solid color blocks in between patterns and decorations along trim lines.

• 센서학회지
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• 제21권2호
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• pp.109-113
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• 2012

We propose an improved interpolating equation to express temperature-resistance characteristics for modern industrial platinum resistance thermometers (PRTs). Callendar-van Dusen equation which has been widely used for platinum resistance thermometer fails to fully describe temperature characteristics of high quality PRTs and leaves systematic residual when the calibration point include temperatures above $300^{\circ}C$. Expanding Callendar-van Dusen to higher-order polynomial drastically improves the uncertainty of the fitting even with reduced degrees of freedom of the fitting. We found that in the fourth-order polynomial fitting, the third-order and fourth-order coefficients have a strong correlation. Using the correlation, we suggest an improved interpolating equation in the form of fourth-order polynomial, but with three fitting parameters. Applying this interpolating equation reduced the uncertainty of the fitting to 32 % of that resulted from the traditional Callendar-van Dusen. This improvement was better than that from a simple third-order polynomial despite that the degrees of the freedom of the fitting was the same.

• Earthquakes and Structures
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• 제9권2호
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• pp.431-453
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• 2015

A destructive earthquake, the magnitude of this earthquake was 7.2, hit Van, Turkey on October 23, 2011. After this devastating earthquake, a moderate earthquake which had 5.7 magnitude on November 9, 2011 occurred in Edremit, Van. These earthquakes caused heavy damages and collapses in many reinforced concrete buildings with loss of lives. In this paper, characteristics of ground motions of these earthquakes were studied and, deficiencies in structural elements and engineering faults such as poor workmanship and quality of construction, soft and weak stories, strong beam-weak column, short column, large overhang, hammering and unconfined gable wall were investigated. According to the observations, it was seen that, low quality of structural materials, lack of engineering services, inappropriate design and construction with insufficient detailing of the structural elements were the main reasons of heavy damages.