• Journal of Power Electronics
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• v.9 no.6
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• pp.960-968
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• 2009

This paper presents a design optimization process for interior permanent magnet synchronous motors (IPMSM) for hybrid electric compressors (HEC) which are applied to hybrid electrical vehicles. A hybrid electric compressor is composed of an electric motor driving section and an engine driving section which is connected to the engine by a pulley belt. A hybrid electric compressor driving motor requires half of the full driving power of a compressor. Even though an engine is not operated at the idling stop mode, the electric motor drives the air-conditioner compressor by itself so that the air conditioning system can produce its minimum cooling capacity. In this paper, the design optimization of an IPMSM for a 42 (V) applied voltage system is studied using the design of experiment (DOE) and response surface method (RSM) of 6sigma. The driving characteristics of this motor drive system are measured and analyzed by experiment.

• Journal of the Korean housing association
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• v.17 no.3
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• pp.89-98
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• 2006

The purpose of this study was to survey curriculum of the department of housing and to develop housing welfare educational program in order to offer the information helpful to the professional of housing education and housing policy makers. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities and public institutions. The major results of this study are as follows. 1) There were 30 universities which has related to the department of housing and the name of major was very various. The half of their curriculum were housing and interior design. 2) The housing welfare educational program should be step by step. The first is basic step to team basic theory of housing and to establish concept of housing welfare. The second is application and practice step of housing design and housing policy and housing economics. The third is specific application step to consider that who were taker from the housing welfare policy and to take practical training in field.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.22 no.3
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• pp.179-199
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• 2018

The paper explores a tri-trophic food chain model with density dependent mortality of intermediate predator. To analyze this aspect, we have worked out the local stability of different equilibrium points. We have also derived the conditions for global stability of interior equilibrium point and conditions for persistence of model system. To observe the global behaviour of the system, we performed extensive numerical simulations. Our simulation results reveal that chaotic dynamics is produced for increasing value of half-saturation constant. We have also observed trajectory motions around different equilibrium points. It is noticed that chaotic dynamics has been controlled by increasing value of density dependent mortality parameter. So, we conclude that the density dependent mortality parameter can be used to control chaotic dynamics. We also applied basic tools of nonlinear dynamics such as Poincare section and Lyapunov exponent to investigate chaotic behaviour of the system.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.2
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• pp.139-146
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• 2018

This work puts forward a theoretical analysis on position estimation performance of interior permanent magnet synchronous motor (IPMSM) according to the injection frequency in carrier-based sensorless operation. The effects of spatial harmonics on inductance and voltage distortion due to the nonideal characteristics of IPMSM and inverter are examined as factors influencing the position estimation performance. Furthermore, the position estimation performance is analyzed by calculating the current at the switching instant in several operating conditions. In summary, the half switching frequency injection is more robust to the nonideal characteristics of IPMSM, especially with light load condition. The validity of the analysis is verified by the simulation and experimental results.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.363-366
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• 2005

The purpose of this study was to survey curriculum of the department of housing and to develop housing welfare educational program in order to offer the information helpful to the professional of housing education and housing policy makers. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities and public institutions. The major results of this study are as follows. 1) There were 30 universities which has related to the department of housing and the name of major was very various. The half of their curriculum were housing and interior design. 2) The housing welfare educational program should be step by step. The first is basic step to learn basic theory of housing and to establish concept of housing welfare. The second is application and practice step of housing design and housing policy and housing economics. The third is specific application step to consider that who were taker from the housing welfare policy and to take practical training in field.

• 한국해양학회지
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• v.29 no.3
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• pp.296-303
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• 1994

Rotating right cylinder of rigid sloping boundaries(top-bottom) is filled with two-layered fluid. External fluid which has the same density as the lower-layer is pumped through the rim boundary at the bottom, and this induces uniform vertical velocity in the interior that produces the Sverdrup type motion such as southward flowing western boundary current with northward interior horizontal motion. The rigid sloping upper boundary meets with lower layer to simulate so called "polar front", and the upper-layer motion influenced by the lower-layer flow has been observed. Barotropic motion in the western part of the basin while baroclinic motion in the eastern half is always present. In particular, both southward flowing eastern boundary flow and western boundary flow meets near the western wall and it induces northward western boundary flow to separate from the boundary With increased ${\beta}$-effect on the upper0layer the width of western boundary decreases and the separated western boundary flow moves into the interior to form an eddy-like motion. Baroclinic Rosebay wave clearly observed in the easter boundary slowly propagates to the west but it seems to be decayed before travelling to the western boundary. A local topograpic effect imposed on the lower-layer causes very sensitive response of upper layer boundary flows. In the east standing0wave0like features are observed in the west whereas the width of the boundary increases without any evidence of the separation of the western boundary flow.This may be due to the gact that even the lower-lauer barotropic motion feels the topography its influence does not propagate into the upper-layer. With large ${\beta}$-effect on the upper-layer,relatively large scale waves whose wavelengths are greater than the internal radius deformation exist in the interior.

• School Mathematics
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• v.17 no.1
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• pp.35-46
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• 2015

In this paper, the teaching contents for angle and measure of an angle in elementary mathematics textbook between Korea and Japan were compared. From this comparison, the following five suggestions were presented as implications to improve the teaching contents for angle and measure of an angle in elementary mathematics textbook in Korea. First, it is necessary to reconsider the way of the definition of angle. There is no use of half line in elementary mathematics, except when to define angle, and the way to define angle and the way to define right angle are not consistent. Second, considering to associate the turning of plane geometrical figures to the $90^{\circ}$, $180^{\circ}$, $270^{\circ}$, $360^{\circ}$ is necessary, and associating them is connected to dealing with point-symmetrical shapes in the fifth grade. Third, there is a need to deal with "the measures of angles are same." in comparing angles. This is possible by superimposing two angles in comparing the measures of them. Fourthly, it is necessary to consider the introduction of the rotational angle. Dealing with the $360^{\circ}$ as the rotational angle is related to explaining that the sum of measures of interior angles in quadrangle is $360^{\circ}$. Fifth, it is necessary to be connected with middle school mathematics curriculum. The term 'straight angle' is used in middle school, and to obtain the sum of the measures of the interior angles of a regular polygon is the contents to be dealt with in middle school.

• Herbal Formula Science
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• v.20 no.2
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• pp.177-186
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• 2012

In this study, we selected some herbal formulation about a series of Chijasi-tang in Dongeuibogam by using web-based open program;Prescription Lineage Graph (http://164.125.206.43/PrescriptionLineageGraph.aspx). And we compared and analyzed the changes of efficacy, major target symptoms of each herbal formulation according to compositional variation of each herbal formulation. Chijasi-tang, first appeared in Sanghanlun, consists of Capejasmine and Fermented soybean, and it is mainly used to treat insomnia due to vexation, heartburn and yellow greasy tongue fur. Capejasmine can clear away irritable feverish sensation in chest by flowing downward the heat, and Fermented soybean can disperse stagnated heat throughout the chest by expelling stagnated heat from the exterior In the case of the heat stagnation caused by relapsing of disease due to overstain, Chisijisil-tang can be used. And if symptom appear more on the upper or exterior than a case of Chisijisil-tang, Seosisi-tang could be more suitable, if half exterior and half interior, Omae-tang could be for it. In addition, if symptom caused by relapsing due to improper diet, Chisijihwang-tang could be proper formulation. In the case of the heat stagnation body inside and jaundice, if it is caused by alcohol, Chijadaehwang-tang could be used for the purpose of urgent purgation, Galchul-tang would be suitable for helping the function of the spleen and the stomach and for treatment of damp-heat of the spleen and the stomach. And if it is caused by pandemic infection, Jangdal-hwan would be good formulation for it. Samhwangseokgo-tang and Yangdokchija-tang could be appropriate formulation for the raging of noxious heat and pathogenic fire caused by febrile disease with toxic yang. Daehwangeum-ja is for severe constipation due to heat-dryness with stagnated fever, Haebaek-tang is appropriate for severe diarrhea due to heat type change of Soeum. According to the result of our investigation, although there are various target causes and symptoms of each herbal formulations, whatever pathogenetic cause is, the stagnated heat in interior side is the basis of symptoms. Therefore, the purpose of including Chijasi-tang in composition of each herbal formulation is treatment of the stagnated heat. For such reason, on the fundamental or ancillary basis of Chijasi-tang plus some herbs for each therapeutic purpose.

• Journal of Fashion Business
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• v.8 no.4
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• pp.68-79
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• 2004

This study aims to understand the history of the Victorian age that attached importance to various designs and aesthetic aspects by art and craft movement, and to present that the Victorian pattern is a factor with unlimited possibility in application and development of the modern textile product designs. Therefore, through documents research home and abroad, I considered the periodical background of the Victorian style, a change course of textile, and the theoretical backing of the Victorian pattern, and I studied and analyzed the cases of being applied in the modern textile product designs by classifying apparel, home interior, and fashion accessories. First of all, in apparel, the Victorian pattern transformed into geometrical form had much relative importance, and secondly, in the home interior, the Victorian pattern was expressed realistically or it was represented more boldly and complexly with new materials or techniques introduced. Thirdly, in fashion accessories, decorative nature was shown in intense design with the real description of the Victorian flower pattern and brilliant colors. With these results, it was found out that when the Victorian pattern was applied in the modern textile product designs, it was the factor that could be expected to make a high value added suitable with the modern sense, and it was the pattern with developmental potential with its unlimited use range. Therefore, based on this study, it is considered that the development of textile product designs utilizing the Victorian pattern and academic research, reorganizing the Victorian pattern in accordance with the modern design should be continued.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.33-41
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• 2013

It is not surprising that senior centers are widely used nationwide as Korea becomes an aging society. This study attempts to figure out senior citizens' needs and evaluations of senior centers in terms of characteristics of their usage and spatial composition. A face to face interview using a questionnaire was conducted on 255 senior citizens who has been using senior centers located in Jangyu new city apartment housing complex. The questionnaire is composed of questions asking characteristics of their usage, evaluations of spatial composition, and respondents' demographic data. Findings are: First, it is found that many respondents visit senior centers everyday and spend 4 to 6 hours a day. Their main activities are meeting friends, taking hobbies, and dining. That is, senior centers play a pivotal role in daily lives of senior citizens. Such characteristics should be taken into account in space design when planning to build a future senior center; Second, it is found that senior centers play a role of auxiliary space for building their sense of belonging and familarity. It is found that furnitures in senior centers are worn out and safety measures are not sufficiently considered; Third, it is found that they highly evaluate flexible spacial composition that could be partitioned or extended depending on occasions even though they prefer independent space; Fourth, it is found that kitchen facilities are not large enough considering the fact that more that half of the respondents have their lunches in senior centers. Even though they do not cook for themselves kitchen space should be large enough for preparing meals simultaneously for a large number people.