• Journal of Korean Society of Water and Wastewater
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• v.23 no.5
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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.

• Fire Science and Engineering
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• v.22 no.2
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• pp.30-37
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• 2008

We have performed the inflammability test for various flooring materials through a radiant heat panel tester by using the specification KSISO 9239-1 (an examination method of flooring materials) that has been set as an international standard for the fire prevention means of interior flooring materials. We have measured the flame spread distance, critical heat flux and smoke density generated by the fire of various flooring materials while using the radiant heat panel tester. The measurement result has shown the burning characteristics different from each other by the respective flooring materials and we could see that the surface materials and construction elements influence greatly on the heat release and smoke generation. We could see that the evaluation method above is an important test method in evaluating the critical heat flux, smoke generation and flame spread distance that are Important factors in studying for fire risks and it is judged that setting and applying a fire evaluation method of flooring materials suitable for the domestic construction use would be relevant.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.315-323
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• 2020

The purpose of this study was conducted to investigate factors influencing college adjustment on nursing freshmen in the distance education during COVID-19. A final sample 165 nursing freshmen was selected from S city, between 31 August and 4 September 2020. Using SPSS program t-test, one-way ANOVA, Pearson's correlation analysis and multiple regression analysis were performed. Factors that influenced college adjustment age, education at the time of admission, motivation of department choice, scholastic achievement. College adjustment showed a positive correlation with academic self-efficacy, critical thinking disposition, problem solving ability. These factors affecting the college adjustment of the subjects were with an explanatory power of 37.7%. Nursing freshmen need to method of class and student guidance that take these factors into account in the distance education during COVID-19.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.1
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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.

• Proceedings of the KIEE Conference
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• 1990.07a
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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.

• Journal of Engineering Education Research
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• v.17 no.3
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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.

• Journal of the Korean Solar Energy Society
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• v.23 no.4
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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.

• Journal of Energy Engineering
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• v.28 no.1
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• pp.30-36
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• 2019

The military has developed and operated a variety of military vehicles. Among them, medium tactical vehicles are developed as vehicles suitable for transporting troops, replacing existing military trucks, which have a significant impact on infantry forces' combat capability. Applying technology to increase fuel efficiency to these critical weapons systems, medium tactical vehicles, increases the distance range, which can reduce effective operational performance and oil costs. In this study, a measure was taken to improve the distance range of Medium Tactical Vehicles by applying an oil temperature control strategy to increase fuel efficiency.

• Current Applied Physics
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• v.18 no.11
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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.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.1
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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.