• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권6호
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• pp.267-272
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• 2002

This Paper deals with the short circuit tests of the three-Phase DC reactor type fault current limiter (FCL) in changing of turns ratio of transformers. The experiment of this paper is a preliminary step to develop the FCL's faculties for an application to high voltage transmission line. So, superconducting coil was made of Nb-Ti, low temperature superconductor, and the ratings of the power system of experimental circuit are 400V/7A class. A three-phase DC reactor type FCL consists of three transformers, six diodes, one superconducting coil and one cryostat. The important point of experimental analysis is transient period, the operating lagging time of circuit breaker. As the results of the experiment, the values are referred to the limitation rate about 77% and 90% when the turns ratio of transformer was 1:1 and 2:1 respectively.

• 산업공학
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• 제10권1호
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• pp.169-187
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• 1997

Recently, in organizations many decisions are being made by groups. And the organization is changing a lot so are groups. To help decision making of changing groups, we need more flexible and more adaptive GDSS. Therefore one of the critical success factors of GDSS is flexibility and incremental improvement. Prior research on specifying design requirements of GDSS suggests generic design requirements. But they are too general to be incorporated directly into system design, because of the disparity between real group and ideal group that the researchers studied. Many design strategies that start from the generic design requirements thus have contingency variables that changes as the characteristics of group change. From the viewpoint of developers, these variables implicate the desirability of flexibility. To achieve flexibility we need new methodology of design and implementation. Nowadays, object-oriented analysis and design methodologies have been progressed to the point that many systems are being developed through these methodologies. In this paper, a design is proposed using Object-Oriented Modeling Techniques(OMT). Exploiting object-oriented paradigm results in a highly flexible and easily upgradable design.

• 한국실내디자인학회논문집
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• 제41호
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• pp.146-154
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• 2003

The purpose of this study is, According to society changing fast, human life is changing in the direction of complexity and variety, the middle class and multiple structure have been generated in relation between architecture and function. Accordingly, considering the analyzed elements of the main floor space planning and relation of the factors in space planning of Seoul s public libraries. The Public Library is variety of function is abstracted to the plan for Space Composition Form from future public library, analysis of “This point of user, how to composition is the space of different function” and “How to is the connection between the educational function and the other function, complexity of space.” With above distinctive themes and the research, the typology of public library in seoul city, At the first, the research shows that the public library is 8 type, and high in typology of “TYPE 7 (A3-B2-Cl)”. Secondary, There appears public library, such as in the satisfaction of the One-Function-User is high in “TYPE 3 (A1-B2-C3)”, in the satisfaction over the Two-Function-User is high in “TYPE 6 (A3-B1-C1)”

• 상하수도학회지
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• 제22권6호
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• pp.647-655
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• 2008

Sewer Rehabilitation Project (SRP) is planed, designed and constructed to perform its intended performance as sewerage delivery systems. Recently, a subject of performance evaluation methodology development for SRP has become a great deal of concern among researchers in Korea. From the view point of Sewage Treatment Plant (STP), however, the estimation of improvement efficiency for SRP is in lack of reliability due to the fact that affections for the treatment efficiency and operating condition are not reflected on SRP design and construction. In this study, statistical methodology was used in the analysis of data, which are taken during 1,186 days ($1^{st}$ Jan. 2005 - $31^{th}$ Mar. 2008) from the influent, effluent and operating conditions of full-scale STP($25,000m^3/d$). Then the effect of SRP on the influent characteristics and operating conditions changing was compared and evaluated. Results from the statistical evaluation show that SRP causes characteristic changes in influent and exerts a significant effect especially on the performance of STP.

• 한국물환경학회지
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• 제35권2호
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• pp.131-144
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• 2019

Climate Change affects the hydrological cycle in agricultural watersheds through rising air temperature and changing rainfall patterns. Agricultural watersheds in Korea are characterized by extensive paddy fields and intensive water use, a resource that is under stress from the changing climate. This study analyzed the effects of climate change on river flows for Geum Cheon and Eun-San Choen watershed using STREAM, a semi-distributed watershed model. In order to evaluate the performance and improve the reliability of the model, calibration and validation of the model was done for one flow observation point and three reservoir water storage ratio points. Climate change scenarios were based on RCP data provided by the Korea Meteorological Administration (KMA) and bias corrections were done using the Quantile Mapping method to minimize the uncertainties in the results produced by the climate model to the local scale. Because of water mass-balance, evapotranspiration tended to increase steadily with an increase in air temperature, while the increase in RCP 8.5 scenario resulted in higher RCP 4.5 scenario. The increase in evapotranspiration led to a decrease in the river flow, particularly the decrease in the surface runoff. In the paddy agricultural watershed, irrigation water demand is expected to increase despite an increase in rainfall owing to the high evapotranspiration rates occasioned by climate change.

• 한국실내디자인학회논문집
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• 제16호
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• pp.68-74
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• 1998

Modern fashion shop is changed by the changing of fashion style. And as purch asing pattern is charged to consuming pattern which has strong individuality functions as space which reflect characteristics of products and consumers in order to present sensitive and in dividual image are also required besides conventional concept as space which simply focused on sale. Meanwhile in the 1980's the fashion presented retro mood modernly by popularization of post-modernism and introduced minimalism that is one of the anti-cultures in the 1960's. Recently minimalistic trends which are expressed by various attempts and a new point of view are introduced to the fashion shop by interior designer. Therefore in this study minimalistic characteristics which appear in the composition of interior space of the modern fashion shop are researched by theoretical consideration and analysis of examples and analysis of examples and consistent direction of fashion shop is presented.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2005년도 추계학술대회 논문집
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• pp.302-305
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• 2005

Recently, many methods to analyze signal have been proposed and representative methods are the Fourier transform and wavelet transform. In these methods, the Fourier transform represents signal with combination cosine and sine at all locations in the frequency domain. However, it doesn't provide time information that particular frequency occurs in signal and denpends on only the global feature of the signal. So, to improve these points the wavelet transform which is capable of multiresolution analysis has been applied to many fields such as speech processing, image processing and computer vision. And the wavelet transform, which uses changing window according to scale parameter, presents time-frequency localization. In this paper, we proposed a new approach using a wavelet of cosine and sine type and analyzed features of signal in a limited point of frequency-time plane.

• 상하수도학회지
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• 제12권2호
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• pp.76-82
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• 1998

It is necessary to calculate the accurate velocity from the hydraulic model for the reliable prediction of water quality changes in water supply system. To verify the hydraulic analysis of the water supply system, fluoride was used as a tracer to calculate the travel time from the injection point to the sampling points. Results from this field experiment indicate that fluoride can be a good conservative tracer while it showed a little longitudinal dispersion along the pipe lines. And the velocity from the model was verified by these travel times and calibrated by changing the ratio of the unaccountable water. When the ratio of the unaccountable water. When the ratio of the unaccountable water was 20%, the error between the estimation of hydraulic model and the real travel time was minimum.

• Journal of the Korean Data and Information Science Society
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• 제18권1호
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• pp.31-40
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• 2007

Many previous researchers tried to analysis relationship between financial index of hospitals such as revenue, expenses, and profit and hospital outcome such as number of inpatient and outpatient or, between that financial index and hospital size including number of hospital beds. However, these studies did not find exact relationship between financial index and hospital efficiency and productivity. Therefore, purpose of the study explores exact relationship between hospital financial outcome and hospital efficiency and productivity using adjusted inpatient days concept from American Hospital Association. Through the empirical analysis, the researchers find that hospital profit has the U-shape quadratic function to operation ratio. 66.9% of operation ratio is changing point and hospitals with 55.8% through 75.0% of operation ration have experience deficit situation. Considering the hospital circumstance, Korean hospitals would be to maintain general hospital type with various specialty departments.

• 디지털산업정보학회논문지
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• 제11권1호
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• pp.157-169
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• 2015

In digital marketing, means of public relations and marketing of enterprises are changing into marketing techniques of predictive analytics. A significant study can be carried out by an analysis of 'the patterns of customers' uses' using big data on major portal sites and SNSs and their correlation with related keywords. This study analyzes the origins of mythological characters in major brands such as Nike, Hermes, Versace, Canon and Starbucks. Also, it extracts related keywords and relevance using big data on portal sites and SNS and their correlation. Nike marketing that reminds people of 'the goddess of victory, Nike' formed a good combination of the brand with relevance. Most of them are based on Greek mythology and have rich materials for storytelling and artistic values in common. Hopefully, this case analysis of foreign brands would become a starting point of discovering the materials of the domestic mythological characters.