• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.68-68
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• 2004

기계기술의 지속적인 발달과 신기술의 개발로 인해 산업전반의 기반 기술인 기계 장치산업은 점점 복잡해지고 또한 다양화되면서 장치시설을 건전하고 신뢰성 있게 유지하고 관리하는 문제가 중요하게 대두되고 있다. 이중 가스 및 오일을 운송하는 배관은 대부분 지하에 매설되어 있고, 다양한 환경에 위치하여 있는데, 이러한 배관은 설치한지 오래되면 여러 가지 환경적 영향에 의해 부식과 같은 결함이 발생되고(Fig. 1과 Fig 2 참조) 이러한 결함이 성장하여 임계크기에 도달하여 대형 재난으로 발전하는 사고가 종종 보고 되고 있으며 이로 인한 경제적, 사회적 손실이 지대하기 때문에 매우 중요하게 인식되고 있다.(중략)

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.43-54
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• 1992

A method of evaluating the velocity components induced by a Havelock source is presented in this paper. The mathematical manipulation of x, y and z-derivative of the Green function of the Havelock source by the use of contour integration on the complex plane has resulted in the expressions that can be readily incorporated with computer program. The accuracy and efficiency that can be secured by the use of the present mathematical expressions have been convincingly found to be highly satisfactory.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.255-258
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• 2000

초음속 유동장 내에 설치된 끝이 막힌 관에 의해 발생하는 공진 현상에는 스크리치 모드 (jet screech mode)와 토출 모드 (jet regurgitant mode)가 있다 이중 토출 모드는 원리상 음향학적 공진과 밀접한 관련이 있다. 본 연구에서는 경계 조건으로, 주어진 강도와 주파수를 갖는 마하 수의 진동을 통하여 압축성 유동장을 가진하는 개념적 모델을 통하여 공진 현상을 모사한다. 비선형 효과의 탐구를 위해 축대칭 오일러 방정식을 수치적으로 풀이하면서, 4 가지의 주요한 파라메터들 (가진 강도, 가진 주파수, 진 동부와 관 사이의 거리, 관의 깊이)을 추출하고 이에 대한 영향을 연구하였다. 또한 비선형 유동 효과에 의해 발생하는, 고전 이론에 의해 예측된 공진 주파수와의 차이를 정량적으로 나타내고 그 원인을 고찰하였다.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.130-137
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• 2004

The ultrasonic attenuation coefficients were measured by interfacial crack length in the adhesive components of double-cantilever beam(DCB). The energy release rate, G, was obtained by the experimental measurement of compliance. The numerical analysis by the boundary element method(BEM) and Ripling's equation was investigated. The experimental results represent that the relation between interfacial crack length for the ultrasonic attenuation coefficient and energy release rate is increased proportionally. A measurement method of the interfacial crack length by the ultrasonic attenuation coefficient was proposed and discussed.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.282-289
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• 2016

A term that has been used since ancient times, 'trickster' means 'a person who performs general tricks'. In other words, a trickster is a person who exhibits his or her intrinsic characteristics by using tricks, or who has a special ability to make any situation work well only for him or herself. This thesis looks for basic concepts and features of tricksters in research undertaken into tricksters to date. It also aims to uncover the trickster side of Maltugi in Talchum (a traditional mask dance). A trickster is a person who tricks, but the characteristic itself is unclear and abnormal. A trickster also has borderline, duplicitous or multi-value characteristics, so it is impossible to merely define him or her as 'a person who tricks'. When dealing with a trickster's characteristics, the 'Liminality' element is very important, because he or she is a person who exists in all the borderlines of space, time, society, and language, and assaults the social order via deceit, play, and the fulfillment of greed. Maltugi in Talchum is a man of humble birth, but he is a character who attacks the Yangban (aristocrats) without hesitation. He is a kind of representative of the people who speaks for the commoners' feelings. At a time of the Three Policies' Disorder and frequent external aggressions, the commoners felt a sense of helplessness against the Yangban, who they viewed as immoral. Maltugi laughs at and depreciates the Yangban through the use of puns, and shows a faithful attitude to the present without being afraid of the result caused by his activity. This implies that he has the characteristics of a trickster.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.87-104
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• 2015

As the influence of Landscape Urbanism has grown, various criticisms on the discourse also have increased. A study on critical opinions of Landscape Urbanism is necessary to fully comprehend the theoretical structure of the discourse and its limitations. This study introduced the concept of Intension and Extension, which is used in the field of Logics and Semiotic, as an analytical tool to interpret various criticisms based on different views in a more objective and synthetic way. After examining the development of criticisms of Landscape Urbanism, 30 texts with important critiques on the theory were selected and analyzed. Criticisms can be classified as internal criticism and external criticism according to specific topics they are engaged with. The study only covers internal criticism as a research scope. The internal criticisms on Landscape Urbanism are re-categorized into topics of theory, practice and the relation between theory and practice. Vagueness of concepts and error in concepts are two types criticism related to the issue of theory. Lexical Ambiguity and Intensional Vagueness are the main causes of conceptual vagueness in Landscape Urbanism. Conceptual vagueness related with the problem of redefining an existing concept through expanding its meaning reveals a structural dilemma. There are three types of criticism included in the topic of practice: absence of practical results, form-oriented practice, and ambiguous identity in practical results. Ambiguous identity is caused by Extensional Vagueness allowing borderline cases. Because these borderline cases overlap with extensions of landscape architecture, it is hard to differentiate projects of Landscape Urbanism and those of conventional landscape architecture. Most criticisms on the relation between theory and practice raise the question on the practical method. Two types of criticism are engaged with the topic of the practical method: errors in practical methods and absence of practical methods. The absence of practical methods is a fundamental problem of Landscape Urbanism which is hard to solve by the proposed solutions. However, these structural problems are not only the weak point but also the factor that is able to prove the potentials expand the scope of Landscape Urbanism. In addition to the results of the study, internal criticisms on Landscape Urbanism should be examined in the following studies in order to predict the next direction of Landscape Urbanism.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.157-161
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• 2004

The eyes, the saying goes, are the windows of the soul. It's the first thing you notice about a person. Therefore, many people want to possess beautiful eyelids. Surgical formation of a palpebral fold and sulcus divides the lid into two well-defined segments (palpebral and pretarsal), producing the double eyelid desired by many Oriental women as well as an increasing number of man recently. Upper lid blepharoplasty is the Oriental eye is one of the variations of standard upper lid blepharoplasty. In Oriental double eyelid surgery, there have been two approaches to form a superior palpebral fold: the buried suture(nonincision) method and the full external incision method. Conventionally, the nonincision technique has been shown to produce little postoperative edema. However, the probability of the fold disappearing is high, and this technique cannot be performed in patients with fatty eyelids. Conversely, the incision technique has contrary characteristics. Recently, partial incision(or semi-open) technique which is combination of mentioned methods is used, this technique is removal of pretarsal tissue, muscle, and/or orbital fat around 2 or 3 incision site to facilitate tarsus-dermal adhesion. Our method is on the basis of this technique, furthermore, compared with conventional semi-open method, Y(Yang's) needle assisted double eyelid operation is more easy, convenient, saving-time method and provide satisfactory results.

• The Journal of Engineering Geology
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• v.3 no.2
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• pp.149-165
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• 1993

Nowadays, the field hydraulic test is still an only method to evaluate groundwater characteristics in subsurface. The results of hydraulic test are very important for the concept model of fracture hydrogeology as well as the geometric pattern of fractures. The hydraulic tests performed in Korea are generally analysed under such assumption as steady radial flow in homogeneous aquifer or along simple geometry of fractures. Also the transmissivity measured in a fixed interval length is equivalent to a sum of individual fracture transmissivities in test legth. The boundary effects of weH hydraulics and the geometry of flow paths are hardly obtained from the test results analysed by a steady flow method. To circumvent this problem, the flow dimensional analysis was attempted from the results of constant pressure injection test carried out in a fractured granite area. A comparison of the hydraulic conductivity values from the transient and steady analysis shows that the latter is about a factor of 2~3 higher than the former. However, it was possible to analyse a flow dimension of each test interval from flow rate variation with time. The upper part of the bedrock(<10m deep) indicates an open boundary and the flow dimension shows nearly steady states, while the lower part of the bedrock(>25m deep) is characterized as sublinear flow dimension with a dosed boundary. In one of the test sections(15m deep), the flow dimension was changed from linear flow to spherical flow. From the experience of this study, one of the immediate problems to be solved is to enhance the field testing equipments, i.e., an accurate flowmeter with autorecording and a pressure detecting device to be able to install in the test section.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.605-610
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• 2009

The either satisfaction levels or limits of tolerance levels felt by the users in the certain space/region should be examined for measuring social capacity on the total amount of vehicles. The reliability of measuring social carrying capacity depends primarily on decreasing the strategic responding biases. To induce the honest responses to preferences, Dichotomous Choice which is specifically known as the Double-Bounded Dichotomous Choice was adopted in this research to suggest the measurement methodology of social carrying capacity on the total amount of vehicles in U-do island. The empirical test was carried out the U-do island, an administrative district of Jeju Special Self-Governing Province. The number of vehicles satisfied by the 10% of residents was 390 and the satisfactory vehicle number was decreased to 132 extended to 90% of residents. This research, based on the political decision making criteria, set up the social carrying capacity in U-do island. The vehicle number satisfied by 50% of residents was 227, which meant the same number of residents turn to be supporter in case of political actions.

• Journal of the Korean earth science society
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• v.35 no.6
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• pp.484-497
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• 2014

This study aimed to investigate high school students' conceptions of plate tectonics. Seventy students (N=70) in their 2 year of high schools in the province of Chungcheong-do participated in this study, and they took a conception test of visual representation. We conducted a semi-structured interview with 10 volunteering participants out of seventy. After learning about the concept of plate tectonics, this study found that participants ended up having alternative conceptions relating to terminology, meaning of colors, plates' movement, plates' boundaries, position and cause of melting, mantle's physical conditions, and driving forces of plate motion. The conceptions that the participants held after class were organically related, which included the meaning of colors, mantle's physical characteristic, and driving forces of plate movement. In addition, the visual representation used for teaching plate tectonics influenced the students' understanding about terminologies, plates' boundaries, position of melting, and the physical characteristic of mantle. The study found that there were the factors of visual representation that caused the learners to create alternative conceptions in learning about plate tectonics.