• 대한전기학회논문지:전력기술부문A
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• 제52권6호
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• pp.333-339
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• 2003

Competition among electric generation companies is a major goal of restructuring in the electricity industry. In electricity market, a huge volume of commodities will be traded through competitive bidding. The choice between uniform and pay-as-bid pricing for electricity auction has been one of most important issues in deregulated electricity market. This paper proposes a constrained Bertrand model for analyzing the electricity auction market of price competition model. The issue of the two pricing rules of uniform and pay-as-bid is studied from the viewpoint of consumer's benefit. This paper also shows that transmission congestion depends on the pricing mechanism. Pay-as-bid pricing gives less possibility of transmission congestion by price competition, and less burden to consumers in the simulation results.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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• pp.663-668
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• 1996

A two-dimensional continuum model for the prediction of the hydrogen mixing phenomena in the containment compartment under the severe accident conditions is developed. The model could predict well the distribution of time-dependent hydrogen concentration for selected HEDL Experiment. For a simulation of these experiments, the hydrogen is mixed uniform over the test compartment. To predict the extent of non-uniform distribution, the dominant factors such as the geometrical shape of obstacle and velocity of source injection in mixing phenomena are investigated. If the obstacle disturbing the flow of gas mixture exists in the compartment, the uniform distribution of hydrogen may be not guaranteed. The convective circulation of gas flow is separately formed up and down of the obstacle position, which makes a difference of hydrogen concentration between the upper and lower region of the compartment. The recirculation flow must have a considerable mass flow rate relative to velocity of the source injection to sustain the well-mixed conditions of hydrogen.

• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.100-105
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• 2012

In previous study, to investigate the impression of the compound lighting based on the AC-Model at the full-size room, the impressions of various compound lighting were completed as compared with that of the uniform lightings through the comparison method (a paired comparison) by Semantic Differential scaling. Also, we examined the effect of the supplementary lighting type increasing the lights at the side of the window and the blind-control lighting type, and they were compared with the existing compound lighting type. In results, pared comparison of the compound lighting and the uniform lighting, indicates that the impression of the compound lighting is generally similar to that of the uniform lighting when there are same ratios of the light from the window. Based on these results, we suggest that the AC-Model might be applied to various conditions. And we also introduce the method for daylighting that it is possible to reduce discomfort glare and to improve visual impressions as the supplementary type and blind-control type on the compound lighting. And it was found that electric power consumption of the compound lighting room was lower than that of the uniform lighting room when as same lighting ratio of the compound lighting and the uniform lighting from the window was provided or there was the lighting distribution simulated to same light ratio from the window. Since the method of the ACModel was described in the experimental condition, additional studies should be performed to determine if this model could be applied to different window configurations, lighting layout and types of a room.

• Nuclear Engineering and Technology
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• 제29권2호
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• pp.110-126
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• 1997

A two-dimensional continuum model for the hydrogen mining phenomena in the containment subcompartment under severe accident conditions has been developed to predict the spatial distribution of the hydrogen concentration. The model can predict the distribution of time-dependent hydrogen concentration for HEDL experiments well. For the simulation of these experiments, the hydrogen is mixed uniform within the test compartment. To predict the extent of non-uniform distribution, the dominant factors such as the geometrical shape of obstacle and velocity of source injection in mixing phenomena are investigated. If the obstacle disturbing the flow of gas mixture exists in the compartment, the uniform distribution of hydrogen might be not guaranteed. The convective circulation of gas flow is separately formed up and down of the obstacle position, which makes a difference of hydrogen concentration between the upper and lower region of the compartment. The recirculation flow must have a considerable mass flow rate relative to velocity of the source injection to sustain the well-mixed conditions of hydrogen. Finally, in order to account for non-uniform distribution of the hydrogen due to the geometrical configuration the maximum-to-average ratio is functionalized.

• 디지털산업정보학회논문지
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• 제15권3호
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• pp.89-100
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• 2019

Uniform and integrated college desks and chairs have low efficiency of loading for transportation and delivery and low efficiency of storage for warehousing due to their simple uniform physical properties, thus increasing logistics costs for companies and decreasing their competitiveness. In an effort to overcome the limitations of previous studies, this study analyzed the stages of logistics for desks and chairs in college lecture rooms via the transportation route including the factory warehouses and local warehouses and via the delivery route from local warehouses by the region to the orderers including college lecture rooms. The study developed a model for the rationalization of corporate logistics by making a variable folding desk and chair capable of distance adjustment according to height to replace the uniform and integrated college desks and chairs in lecture rooms. A model was developed between the old uniform and integrated college desks and chairs and the new variable folding desks and chairs for three scenarios of cost development including product storage costs, transportation costs from the specialized factory warehouses to the local warehouses by the region, and delivery costs from the local warehouses to college lecture rooms as the orderer. For the generalization of the model, it was applied to each of the 90%, 95%, and 99% service levels.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.68-73
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• 2021

The 'Good School Uniform' development project was conducted in consultation with Gyeonggi-do and the Gyeonggi Provincial Office of Education. The aim is to find various ways to supply school uniforms reflecting the latest trends at low prices using high-quality textile materials produced in Gyeonggi-do. From 2015, when the 'Good School Uniform' development project started, to the present, various events and fairs are making great progress. However, there are several problems in actually wearing each middle and high school student. In order to satisfy the characteristics of each school and the satisfaction of parents and students together, it is necessary to not only conduct practical research such as closer customer satisfaction surveys, industry-academia-research networks, expert interviews, and surveys, but also several supplements such as consultations between practitioners. There are many domestic studies on the development of school uniform design, but the research on the revitalization plan according to the free school uniform support is very insufficient. Moreover, it is not easy to find recent studies on the development of 'Good School Uniforms'. This study intends to study how to build a system so that the Gyeonggi-do 'Good School Uniform' development project can be used as a role model. In addition, it is expected that this study will be used as basic data for building a nationwide system such as public brand development and collaboration with small domestic companies.

• Structural Engineering and Mechanics
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• 제84권4호
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• pp.517-530
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• 2022

In re-assessing the Jacket-type fixed steel structures, the current standards often allow the simplicity of corrosion sections using local buckling or equivalent section approach to applying empirical formulae of frame stress and resistance analyses. However, those approaches can lead to significant errors for non-uniform corroded frames in a specific area, including force distribution, stress, and allowable strength of the tubular section, compared to the actual cases. This paper investigates a suitable approach to determine the actual stress on non-uniform corroded tubular frames under compression through the non-linear ABAQUS model by considering the effect of large deformation on the frame axis and the frame section. There are 3 scenarios of interest. In the 1st and 2nd scenarios with simple corrosion cases, the stress ratios using the numerical model and theoretical formulae correspond to the calculation of allowable strength reduction ratios in standards. However, scenario 3, which describes non-uniform corroded sections based on survey data, provides considerable differences in results. Therefore, it proves the reliable and effective results when using this method to analyze the resistance of the actual corroded section in the Jacket platforms.

• 복식
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• 제50권8호
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• pp.43-55
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• 2000

The objectives of this study were to investigate the differences of image evaluation of baseball uniform by uniform design and perceiver's gender. and to examine how baseball uniform preferences vary according to perceiver's gender. Stimuli consisted of 12 color photographs of a male model wearing a baseball uniforms which were manipulated according to the color of shorts and pants. A semantic differential scale of 23 items were used to evaluate the image of the stimuli. Subjects were 288 males and females. Five dimensions derived to account for the image of baseball uniform. These were manly, ability, activity, preference, and visibility. Wearing of red shirts had a positive effect on the evaluation of ability, activity, and visibility. Dark blue shirts had a positive effect on the evaluation of preference. Grey uniforms had negative effects on the evaluation of ability, activity, and visibility. Men liked white uniforms and vertical stripes uniforms of black and white more than dud women. Women talked dark blue shirts more than did men.

• 한국정밀공학회지
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• 제25권3호
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• pp.157-164
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• 2008

While developing physical prototype from CAD model, rapid prototyping mainly focuses on two key points reducing time and material consumption. So, we have to change from a traditional solid model to building a hollowed prototype. In this paper, a new method is presented to hollow out solid objects with uniform wall thickness to increase RP efficiency. To achieve uniform wall thickness, it is necessary to generate internal contour by slicing the offset model of an STL model. Due to many difficulties in this method, this paper proposes a new algorithm that computes internal contours computing offset model which is generated from external contour using wall thickness. Proposed method can easily compute the internal contour by slicing the offset surface defined by the sum of circle swept volumes of external contours without actual offset and the circle wept volumes. Internal contour existences are confirmed by using the external point. Presented algorithm uses the 2D geometric algorithm allowing RP implementation more efficient. Various examples have been tested with implementation of the algorithm, and some examples are presented for illustration.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.667-670
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• 2002

Uniform metal-droplet deposition using laser is analyzed. Using the variation principle and modeling the semi-solid phase as a non-Netwonian slurry, this model can greatly save the computational expenses that conventional numerical procedures have suffered from. The simulation results revealed that the developed model could reasonably describe the collision behavior of molten metal with solid surface. Simulations were made with variation of the falling distance and time.