• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.5
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• pp.297-304
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• 2000

The motor for torpedo propulsion is needed the compact and short rating high power characteristics. This paper describes the development of the motor through the theory and Finite Element Method(FEM) analysis for Brushless Direct Current Motor(BLDCM) of 7 phase 6 poles. Back EMF, inductance and eddy current loss were analyzed. The proposed methods like magnetic wedge acquired by these FEM analysis were introduced. Phase-leading angle using encoder was used. Test results on the motor of 7 phase 6 poles were showed the validity of proposed methods and phase-leading angle.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.3_4
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• pp.298-309
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• 2003

This paper was done to identify the types and the characteristics of street fashion of men living in world fashion-leading cities. 608 male photos taken on the main streets of 4 world fashion-leading cities such as London, New York, Paris, Tokyo were used as data. Photos were viewed by students and classified according to overall images and the common aspects of characteristic style. Fashion images of male were classified into 11 groups, which were suits, casual, hip-hop, rockers/punks, hippies, ethnic, western, military, new romantic, skirt, androgynous. Frequency distribution showed that casual image was mostly preferred and 1311owe4 by suit, rocker/punks. Military and hippies were least favored. In each category, almost every style looked unique and creative as a result of mixing and cross-coordination of different clothing items.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.268-270
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• 1995

This paper proposes a novel PWM technique for a three phase current fad type converters. A minor loop compensation method is introduced to compensate leading current and to minimize input line current (Iu) distortion resulting from the resonance between AC filter capacitor and source inductance of power system. This PWM converter has excellent characterics as next. The control system is simply designed, and the operation with unity power factor can be easily obtained by automatic compensating the leading current of the filter circuit. Also. the three phase sinusoidal input current can be obtained.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.3
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• pp.83-90
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• 2004

This paper proposes a tool path generation method for machining impellers with 5-axis machining center. The shape of impeller is complex, being composed of pressure surface, suction surface and leading edge, and so on. The compound surface which is made of ruled surface such as pressure surface and suction surface and leading edge such as fillet surface, makes the tool path generation much complicated. To achieve efficient roughing, cutting area is divided into two region and then tool radius of maximum size that do not cause tool intereference is selected for shortening machining time. In finishing, accuracy is improved using side cutting for blade surface and point milling for leading edge.

• Wind and Structures
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• v.29 no.4
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• pp.271-277
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• 2019

This work deals with designing the aircraft wing and simulating the flow behavior on it to determine the aerodynamically efficient wing design. A NACA 4412 airfoil is used to design the base wing model. A wing with a rectangular planform and the one with curved leading edge planform was designed such that their surface areas are the same. Then, a comprehensive flow analysis is carried out at various velocities and angle of attacks using computational fluid dynamics (CFD) and the results were interpreted and compared with the experimental values. This study shows that there is a significant improvement in the aerodynamic performance of the curved leading edge wing over the wing with rectangular planform.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.3037-3047
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• 2000

This paper describes a method of tracking a close leading vehicle by color image processing using the pairs of tail and brake lights. which emit red light and are housed on the rear of the vehicle in stop-and-go traffic condition. In the color image converted as an HSV color model. candidate regions of rear lights are identified using the color features of a pair of lights. Then. the pair of tailor brake lights are detected by means of the geometrical features and location features for the pattern of the tail and brake lights. The location of the leading vehicle can be estimated by the location of the detected lights and the vehicle can be tracked continuously. It is also possible to detect the braking status of the leading vehicle by measuring the change in HSV color components of the pair of lights detected. In the experiment. this method tracked a leading vehicle successfully from urban road images and was more useful at night than in the daylight. The KAV-Ill (Korea Autonomous Vehicle- Ill) equipped with a color vision system implementing this algorithm was able to follow a leading vehicle autonomously at speeds of up to 15km!h on a paved road at night. This method might be useful for developing an LSA (Low Speed Automation) system that can relieve driver's stress in the stop-and-go traffic conditions encountered on urban roads.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.1
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• pp.38-49
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• 2015

Past study of tsunami heavily relied on the numerical modelling using 2D Boussinesq Eq. and Solitary wave. Lately, based on the fact that numerically simulated run up heights based on solitary wave are somewhat smaller than the measured one, Leading Depression N (LDN) Wave has been elaborated, which can account the advancement of a shore line before tsunami strikes a shore. Thereafter it is reported that more accurate simulation can be possible once LDN is deployed. On the other hand, there were numerous reports indicating that stable LDN wave can't be sustained in the hydraulic model test. These conflicts between the hydraulic model tests and numerical results have their roots on the assumption made in the derivation of Boussinesq type wave model such as that wave nonlinearity is equally balanced with wave dispersiveness. Hence, in the numerical simulation based on the Boussinesq type wave model, wave dispersiveness is inevitably underestimated, especially in deep water. Based on this rationale, we developed the modified methodology for the generation of stable LDN wave in the 3D numerical wave flume, and proceeded to numerically analyze the depression effect of Hybrid Breaker on the run up height due to tsunami using the Navier Stoke Equation. The verification of newly proposed wave model in this study was carried out using the run up height from the hydraulic model test. It was shown that Hybrid Breaker consisting of three water chamber and slope at its front can reduce 13% of run up height for H = 5m, and 10% of run up height for H = 6m.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.2
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• pp.9-21
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• 1988

This study was to obtain effect of stem leading time and angles on the growing and flowering in climbing rose. The results were as follows : In the rambler type, climber type and pillar type, differences of bud size were decreased between upper ports and lower parts as leading angles were close to the horizon. And bud type was like a long-egg shape. regardless of growing type, differences of stets diameter between upper parts and lower parts were decreased when the angles were leaded horizon. In order to increase rate of shooting and flowering, regardless of leading time, rambler type was shooted in a short period and flowered evenly, from upper to lower parts of stem as leading angles were horizon. But in the case of 45$^{\circ}$, the rate of lower parts was nearly zero. In climber type, shooting and flowering was only happened to the lower parts of stem when leaded during growth stage according to leaded horizon. These phenomena are supposed that shooting and flowering rate are influenced by not only apical dominance but degree of bud growth. Meanwhile, pillar type was shooted and flowered evenly to lower parts when the stem was leaded during growth stage or not leaded completely. But in creeper type, there was no connection with the leading. Therefore, this type had better not leaded. Length of flowering stem, regardless of growing type, was equaled when leaded during growth stage according to leaded horizon.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.7-16
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• 2011

This is a study on operation system's application method for leading-in public bike operation system through researching on case study at home and abroad, and situation research in Naju city. In the 1st research, studied about the main problems showed at application cases of public bike system at domestic and overseas, such as using time, danger for be stolen and damaged. 2nd research focuses on necessarily of leading-in operation system to be used easily by city residents and travelers of Naju City which is the scheduled city for leading-in public bike system. 3rd research is on the basis of the result showed in 1st and 2nd research, supplied some problems' solving method for France Veblib System, such as lending and rental process using mobile, system operation process, communication process. Also, supplied the application method for problems showed at 1st and 2nd research and civil service proposal. The leading-in method study on public bike operation system was done through above research, also case study at home and abroad, situation study, and rental program module development, and this operation system is worked as an model operation system in Naju City. The future study of leading-in operation system will be more effective by means of summing up test running result.

• 대한공업교육학회지
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• v.33 no.1
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• pp.44-66
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• 2008

As the way to intensify vocational education, the places to learn and work merge into one educational system and teaching-learning methods that were pointed at lecturer level are adjusted to learners level. However, the current education environment of vocational highschool doesn't keep up with a new teaching and learning paradigm due to the lack of government-level support and the lecturer level education as well. In this paper, we present a novel learner-leading e-Learning teaching & learning contents framework that intensifying self leading education. In this framework, we concern the ability of self leading, space perception and lesson preparation, preferences of multimedia, scholastic aptitude level and achievement level of students in vocational highschool. Moreover, with following the protocol of the suggested model, we generate a new e-learning contents applying to the subject "Introduction to industry". Especially, to perform better quality of contents, we have survey the whole content of the subject and assorted part of it that would work best with learner-leading e-Learning teaching and learning contents. As we tentatively apply e-learning contents to students in vocational highschool, 79% of them replied that contents brought advantages to get school accomplishment, whereas 19% of students answered in negative that contents wasn't helpful than we've expected. Therefore, the statistical results probe that the e-learning contents we proposed show positive effect, and we analyzed the reasons that deteriorate the effects of contents as shortage of budget and copyright limitation.