• 한국화재소방학회논문지
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• 제16권2호
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• pp.33-37
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• 2002

본 연구에서는 소화용수 제어에 사용되고 있는 버터플라이 밸브의 디스크에 대한 유체역학 토크특성을 연구하였다. 자유-유선 이론이 유체역학 토크특성을 예측하는데 응용되었다. 디스크의 토크특성은 토크 이론식에 밸브 디스크의 개도각과 주변속도가 보정되었고, 보정식이 추가되었다. 디스크의 토크특성은 허브의 두께와 직경 비에 대해 조사하였다. 예측결과는 버터플라이 밸브의 전형적인 특성을 보여줌으로서 성공적인 것으로 보여진다. 디스크 주변의 속도분포를 가시적으로 확인함으로서, 자유-유선이론이 디스크의 토크특성를 예측하는데 사용될 수 있음을 확인하였다.

• 지식경영연구
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• 제15권4호
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• pp.15-34
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• 2014

Creative problem solving has become an important issue in many fields. Among problems, dilemma need creative solutions. New creative and innovative problem solving strategies are required to handle the contradiction relations of the dilemma problems because most creative and innovative cases solved contradictions inherent in the dilemmas. Among various kinds of problem solving theories, TRIZ provides the concept of physical contradiction as a common problem solving principle in inventions and patents. In TRIZ, 4 separation principles solve the physical contradictions of given problems. The 4 separation principles are separation in time, separation in space, separation within a whole and its parts, and separation upon conditions. Despite this attention, an accurate definitions of the separation principles of TRIZ is missing from the literature. Thus, there have been several different interpretations about the separation principles of TRIZ. The different interpretations make problems more ambiguous to solve when the problem solvers apply the 4 separation principles. This research aims to fill the gap in several ways. First, this paper classify the types of contradiction relations and the contradiction solving dimensions based on the Butterfly model for contradiction solving. Second, this paper compares and analyzes each contradiction relation type with the Butterfly diagram. The contributions of this paper lies in reducing the problem space by recognizing the structures and the types of contradiction problems exactly.

• 한국전산유체공학회지
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• 제19권1호
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• pp.21-26
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• 2014

Butterfly valve is a valve that controls fluid flow depending on the size of the opening angle. In general, the size of the opening angle of the valve increases, the fluid flow has also increased sharply. However, sometimes, in a specific piping system, a particular operating condition is needed that the fluctuation of the fluid flow should not have large amount although the size of opening angle of the valve become larger. In butterfly value, the shape of a typical thin plate, it is impossible to control a minute fluid, but in thick plate type, it is possible. In this study, we got the fluid flow control characteristics and pressure drop through both a numerical method and an experimental method about thick plate type. The numerical result and experimental result of flow coefficient show a similar pattern. In addition, we could find that minute fluid flow control was possible in the area of small size of the opening angle.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.142-143
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• 2008

In the present work, high-speed video images of the ground take-off flight of a live butterfly were captured and their dynamic motions during the first full-stroke were analyzed. To capture the dynamic images of the take-off motion, the experimental setup consisted of a high-speed camera, a Xenon lamp as a light source and a transparent chamber of $15^W{\times}15^L{\times}17^H$ $cm^3$ in physical size. The ambient temperature and supplementary lighting devices were precisely controlled. The weight and wing span of the butterfly tested in this study was 104 mg and 63.14 mm, respectively. The ground take-off images were captured with 4000 fps with a spatial resolution of (1024${\times}$512) pixels. The period of the first full-stroke was 80.5ms and the flapping speed of downstroke was 2 times faster than that of upstroke. As a result, butterflies used the fling and near-clap motion to generate lifting force and an interesting take-off behavior of early pronation and downstroke was observed.

• 환경영향평가
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• 제21권1호
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• pp.53-61
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• 2012

This study makes an attempt to appraise how much successful both (Ham-Pyung) Butterfly Festival and (Mu-Ju) Firefly Festival are in the view point of ecology-friendly effects, and based on this appraisal, searches for desirable and developmental directions of other eco-festivals. The empirical analysis of the study shows that even if the Butterfly Festival turns out to be more famous than the Firefly Festival, the latter is confirmed to be more eco-friendly than the former. The fact that the latter is more eco-friendly seems to be due to the fact that the subject matter, that is the theme, of the festival is the fireflies which are not only natural monuments but also peculiar in-site-resources specific to Mu-Ju. This fact suggests that the other eco-festivals, newly emerging ones in particular, need to find and designate in-site-resources inherent in their regions as the theme, as far as possible.

• 영어영문학
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• 제54권4호
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• pp.579-597
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• 2008

This article discusses David Henry Hwang's M. Butterfly as a suggestive text for examining Western masculinity in crisis in the post-imperialist age, in which territorial imperialism is no longer valid. Previous scholarship on M. Butterfly has centered around the interlocking dynamics of imperialism, racism and sexism. Such critical attentions focus on how Hwang deconstructs racialized significations of the East and the West. In these discussions, the issue of gender is often addressed merely as a trope to represent the power relations between the East and the West. As such, gender as well as sexuality is highlighted as the very source of subversion of the power relations. My discussion departs from a critique of the gendered trope of the East and the West, highlighting a postmodern agent, the allegedly feminized character Song Lining: a Chinese actor who passes for a woman for political purposes in postcolonial China. Remaining an "inappropriate/d other" in the gendered imperialist discourse, Song becomes an emergent subject, who is capable of playing gender ambiguity for reclaiming a devalued identity, that of homosexual Asian man. Discussing how the central character Rene Gallimard's masculine identity is constructed in a cross-cultural space and how it evolves, I also argue that Gallimard's melancholic death signifies a historical unsustainability of imperialist masculinity in the postmodern/postcolonial age since World War II.

• 한국산업융합학회 논문집
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• 제25권1호
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• pp.131-139
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• 2022

The exchange of goods over the sea is a situation in which the amount of trade between countries is gradually increasing. In order to maintain the optimal operating condition, the ship maintains stability and optimal operating conditions by inserting or withdrawing ballast water from the ballast tank according to the loading condition of cargo capacity is also increasing. Control valves play an important role in controlling fluid flow in these pipes. When the flow rate is controlled using a control valve, problems such as cavitation, flashing, and suffocating flow may occur due to high differential pressure, and in particular, damage to valves and pipes due to cavitation is a major problem. Therefore, in this study, the cavitation phenomenon is reduced by installing orifices at the front and rear ends of the high differential pressure control butterfly valve to reduce the sudden pressure drop at the limiting part of the butterfly valve step by step. The flow coefficient according to the shape of the orifice, the degree of cavitation occurrence, and the correlation were analyzed using a CFD(Cumputational Fluid Dynamics), and an optimal orifice design for reducing cavitation is derived.

• 한국경제지리학회지
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• 제9권2호
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• pp.197-210
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• 2006

본 연구는 우리나라에서 성공한 문화관광축제로 인정을 받고 있는 함평군의 나비축제를 사례로, 축제의 발굴과 뿌리내림, 그리고 전개과정에 나타난 특징을 고찰하였다. 함평나비축제는 제1회를 시작으로 지금까지 제7회의 축제가 개최되었고, 축제 개최를 통해 생태적으로 건강한 농촌이라는 함평군의 친환경적 이미지를 만들어 농촌의 쾌적성을 상품화 하는 데 성공하였다. 그리고 축제의 성공은 지역농산물의 판매 증가, 지역경제의 활성화, 지역주민의 일체감 조성 등에 커다란 기여를 하였다. 특히 제1회 축제를 개회한 이후 축제를 방문하는 관광객은 꾸준히 증가하였고, 관광객의 재방문율도 지속적으로 증가하였다. 관광객들은 축제가 매년 향상되고 있다고 인식하였고, 이런 변화는 프로그램에 대한 인지도, 참여 프로그램에 대한 선호도, 프로그램 구성 등에서 구체적으로 나타났다. 축제의 경제적 효과도 증가하고 있으며, 축제의 개최비용은 매년 증가하여 제7회에는 제1회보다 약 2.7배가 늘어났다. 축제개최의 수입도 제1회의 약 63억원에서 제7회의 105억원으로 크게 증가하였고, 지역내 고용과 소득증대에 기여하였다.

• 한국응용곤충학회지
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• 제50권2호
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• pp.115-123
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• 2011

굴업도는 면적 $1.71\;km^2$의 작은 섬이지만 멸종위기종인 왕은점표범나비가 많이 서식하고 있다. 이 연구는 굴업도에서 왕은점표범나비의 서식실태 파악을 위해 2010년에 방형구법, 표시-포획법과 선조사법으로 조사하였다. 조사가 충분하지 않았지만, 왕은점표범나비의 유충은 4,467마리 또는 6,700마리, 성충은 약 1,000마리가 서식하는 것으로 추정되었다. 왕은점표범나비는 최우점종으로 전체 나비 개체수의 32%를 차지하였다. 또한 총 28종의 나비가 발견되었고, 이 중 3종은 미접이었다. 1938년부터 2010년까지 전국의 왕은점표범나비 분포지를 시대별로 비교한 결과 2000년대 이후 급감하였으며, 현재 중북부 지역과 서해 도서지역에 제한적으로 서식하는 것으로 나타났다. 굴업도에서 왕은점표범나비가 많이 서식하는 것은 자연상태의 초지가 많으며, 가축의 방목이 적당한 서식처를 제공하기 때문이다.

• 한국초등과학교육학회지:초등과학교육
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• 제33권2호
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• pp.306-321
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• 2014

This study aims to analyze difficulties that pre-service elementary teachers experience in investigating the life cycle of a common cabbage butterfly in person. As difficulties they face during the process of this research, they pointed out collecting eggs, observing molting, creating environments for a breeding cage, feeding, building a breeding cage, and making butterfly specimens. Out of all the environmental difficulties related to their school fields, they pointed out a difficulty of time management most of all, followed by placing a breeding cage in the classroom and the lack of microscopes for observation. In regard to difficulties related to their evaluations on students' activities, they found it difficult to evaluate students' activity with the life cycle of an insect in the aspect of knowledge and even to set evaluation criteria. Besides, many of them responded that it would be appropriate to evaluate a research on the life cycle of an insect through a portfolio or an observation journal. In regard to difficulties in terms of teachers' knowledge, they found it difficult to understand insect molting, metamorphoses, complete metamorphoses, incomplete metamorphoses, the structure of an insect body, and how to distinguish a female insect from a male one. In regard to the application of class models, they knew it is important for students to have various experiences through direct observation, so the experience-based learning model was proper for the process of observing the life cycle of a common cabbage butterfly. However, they found it difficult for students to observe each stage of the life cycle in person.