• 상하수도학회지
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• 제23권5호
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• pp.655-667
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• 2009

An experimental study is performed on reducing the pollutants supplied by storm water through enhancing efficiency of SS from the detention storage tank where CSOs are kept temporarily before discharge to the receiving water system. SS removal efficiency is investigated in accordance with various conditions of the detention pond-such as its length, the existence of training wall, and the use of gravel filling. The removal efficiency is strongly affected by the detention pond's length until the critical falling distance of the suspended solids is reached. For cases where the tank has a length longer than this critical condition, the removal rate shows less sensitivity. To enhance the SS removal efficiency of tanks of shorter than the critical length, we studied alternative types of tank in which inside training walls are installed. The results showed improvement of 14 to 37% in removal efficiency in 2hours detention(2 training walls). The important factor in achieving a high SS removal rate is ensuring the critical length of the detention pond, but for the cases where the basin length cannot be guaranteed, baffles or a gravel filling scheme may be introduced to attain considerable efficiency. The results of studying and comparing different storage tank conditions show that, in terms of elimination efficiency, a storage tank with gravel filling and training walls > a storage tank with gravel filling > a storage tank with training walls > an empty tank. The experimental results should contribute to development of related further research, by empirically verifying the already assumed importance of critical falling distance, training walls, and gravel filling schemes.

• 한국화재소방학회논문지
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• 제22권2호
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• pp.30-37
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• 2008

건축용 바닥재의 화재예방을 위하여 국제규격으로 정해져 있는 바닥재 시험평가 방법인 KSISO 9239-1을 이용하여 각종 바닥재에 대한 연소성 시험을 복사열 판넬 시험기를 사용하여 실시하였다. 복사열 판넬 시험기를 이용하여 각종 바닥재에 대한 화염 전파거리, 임계 열류량 그리고 연기 발생농도 측정하였다. 측정결과 바닥재의 구성 물질 별로 서로 다른 연소특성을 나타내었으며, 바닥재의 표면 재질 및 구성성분이 열 방출과 연기 발생량에 있어 중요한 영향을 미치게 된다는 것을 확인할 수 있었다. 위의 평가방법은 화재위험성을 연구하는데 중요한 인자인 임계 열류량, 연기 발생량 및 화염 전파거리를 정량적으로 평가하는 중요한 시험방법임을 알 수 있었고 국내 건축용 바닥재 화재평가 방법을 국내실정에 맞게 제정 및 적용하는 것이 적합할 것으로 판단되었다.

• 디지털융복합연구
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• 제18권10호
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• pp.315-323
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• 2020

본 연구의 목적은 코로나19 원격 교육에서 간호대학 신입생의 대학생활 적응에 영향을 미치는 요인을 확인하기 위해 시도되었다. 자료는 2020년 8월 31일부터 9월 4일까지 S시 소재의 간호대학 신입생 165명을 대상으로 하였다. 자료분석은 t-test, one-way ANOVA, Pearson 상관분석, 다중회귀 분석을 이용하여 분석하였다. 일반적 특성 중 대학생활 적응과 관련된 요인은 연령, 입학 당시 학력, 입학 동기, 성적이었다. 대학생활 적응은 학업적 자기효능감, 비판적 사고 성향, 문제해결능력과 유의한 양의 상관관계에 있었으며, 이들 변수는 대학생활 적응을 37.7% 설명하였다. 따라서 코로나19로 원격 교육을 받는 간호대학 신입생의 대학생활 적응을 위해 학업적 자기효능감, 비판적 사고 성향, 문제해결능력을 고려한 수업방식과 학생지도가 필요하다.

• 한국경영과학회지
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• 제19권1호
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• pp.41-52
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• 1994

Imprecision of evaluation or lack of prior information about preference can be an obstacle for decision maker in representing his strict preference. Therefore, fuzziness of preference can take place, and in addition, intransitivity or incomparability of preference becomes the critical difficulty in making complete preorder of alternatives. In order to get better solution and to improve practical usufulness, MCDM should be established as a pseudo-criterion model that include fuzzy preference. In this paper, we suggest a pseudo-criterion model that can make complete preorder of alternatives by metric distance measure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.121-124
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• 1990

Distance relaying is one of the most commonly used protection schemes in the high voltage transmission systems. In this scheme, coordination between the primary and backup relays is very critical for the power system security. This paper reports an rule-based methodology for checking and correction of miscoordination problems in the distance relaying. Diagnosis rules achieving an accurate but simple checking have been developed through the geometric analysis of the impedance characteristics of the distance relays. Heuristic rules having the pratical power for miscoordination correction are suggested. The proposed method has proved very effective through the several case studies on the actual systems.

• 공학교육연구
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• 제17권3호
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• pp.34-41
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• 2014

In distance education, use of proper software tools can greatly enhance student's attention and learning efficiency. In such software tools, offering diverse multimedia information is one of the most critical factors. However, integration and synchronization of the various media types has been relatively difficult parts of implementation. This paper proposes a prototype system that uses a metafile and event handling mechanism for the uniform treatment of various media types. This event-level integration and synchronization of multimedia makes the implementation relatively simple. With this approach, instructor's behaviors are automatically recorded, and the instructors can freely choose and show any type of multimedia contents while lecturing. Current commercial or non-commercial lecture management systems could incorporate this approach, so that the distance education market could be expanded with richer multimedia contents.

• 한국태양에너지학회 논문집
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• 제23권4호
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• pp.97-107
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• 2003

Recently, the apartment building has been constructed in large quantities to provide housings due to the gravitation of population towards large cities. However, we're faced with a critical problem of deterioration of our dwelling environment caused by the trend toward high-rise apartment which could be an obstruction in obtaining sufficient sunlight. Therefore, there have been several legislative actions against infringement on the right of sunshine. In the building law, sunshine hours and the minimal separated distance between apartments are regulated as the criteria for the site planning, However, the minimal separated distance was defined without consideration of the parameters like building orientation and thermal effect of the sunshine hours in the site planning for the apartment building. In this study, the sunshine hours and heating energy during the underheated season for various arrangements in site planning are carefully considered and analyzed.

• 에너지공학
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• 제28권1호
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• pp.30-36
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• 2019

군에서는 다양한 전술차량들을 개발하여 운용하고 있다. 그 중 중형전술차량은 기존 군용트럭을 대체하면서 병력수송에 적합한 차량으로 개발되어 보병부대의 전투력에 중요한 영향을 끼친다. 이런 중요한 무기체계인 중형전술차량에 연료 효율을 높이는 기술을 적용한다면 항속거리가 증가되어 효과적인 작전수행과 유류비를 감소시킬 수 있다. 본 연구에서는 연료 효율을 높이기 위해 오일 온도 제어 전략을 적용하여 중형전술차량의 항속거리를 향상시키기 위한 방안에 대해 연구하였다.

• Current Applied Physics
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• 제18권11호
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• pp.1393-1398
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• 2018

We have investigated Bernal-stacked tetralayer graphene as a function of interlayer distance and perpendicular electric field by using density functional theory calculations. The low-energy band structure was found to be very sensitive to the interlayer distance, undergoing a metal-insulator transition. It can be attributed to the nearest-layer coupling that is more sensitive to the interlayer distance than are the next-nearest-layer couplings. Under a perpendicular electric field above a critical field, six electric-field-induced Dirac cones with mass gaps predicted in tight-binding models were confirmed, however, our density functional theory calculations demonstrate a phase transition to a quantum valley Hall insulator, contrasting to the tight-binding model prediction of an ordinary insulator.

• 한국의상디자인학회지
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• 제23권1호
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• pp.1-18
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• 2021

The purpose of this study is to analyze and understand the approach of critical fashion by comprehending the appropriation of art as a sociocultural phenomenon that influences contemporary fashion. This study inquired into the relevant literature to explain the theoretical background behind critical fashion, and conducted a case study using exhibition catalogues, exhibition works, articles, fashion magazines, and fashion-related websites in order to examine cases of appropriation strategies. As a subversion of meaning by using an existing transposable object image to deliver an experience unlike the actual image, subversive appropriation in critical fashion takes existing things as they are and rearranges them with the purpose of subverting social values while having its subversive style of appropriation. Referring to a style that focuses on labelling the distance between the subject, that refers and that which is referred to, referential appropriation has been reprogramming existing things with an internal and introspective attitudes. In other words, from an exploitative style of appropriation aimed at expanding the meaning with found in objects by avant-garde fashion designers, to a subversive style of appropriation aimed at subverting meanings with transposable objects by conceptual fashion designers, there has been a change toward the referential style of appropriation aimed at expanding artistic forms with created objects critical fashion designers.