• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.6
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• pp.536-543
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• 2004

Slotless Permanent Magnet Brushless DC Motor(PM BLDC) with the characteristics of high speed and power density has been more widely used In Industrial and factory machine. Generally, PM BLDC meter is necessary that the three Hall-lCs evenly be distributed around the stator circumference in case of the 3 phase motor. The Hall-ICs are set up in PM BLDC Motor to detect the main flux from the rotor. therefore the output signal from Hall-ICs is used to drive a power transistor to control the stator winding current. However, instead of using three Hall-ICs, if it used only one Hall-IC, we can estimate information of the others phase in sequence through a rotor This paper identified the characteristics and performance by using one Hall-IC with the 3-phase, 2-pole, 6-slot PM BLDC motor.

• Journal of architectural history
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• v.3 no.1
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• pp.9-22
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• 1994

In Pyonjon, Kings received high-ranked officials, heard preachings of classical literatures. State affairs were also discussed here. In palaces of the Chosun Dynasty, Pyonjon used to be regarded as the most important building second to the main hall. In Changduk palace, Sonjongjon was the original Pyonjon. But, before the end of the 17th century, Huijongdang began to be called Pyonjon, and after the 19th century, Huijongdang became Pyonjon officially. Sonjongjon was located beside the main hall, while Huijongdang before the King's bedroom. The floor of the former building was covered with brick but Huijongdang covered with ondol and wooden floorings. In Sonjongjon, every man sit on the chair, but in Huijongdang King and officials used to sit down on the floor. The fact that Huijongdang became Pyonjon replacing to Sonjongjon meant change of building arrangement in the palace and usage of inner space.

• Journal of architectural history
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• v.28 no.3
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• pp.7-18
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• 2019

This study analyzed "Bukgwol Dohyeong (Drawing Plans for the Northern Section of Gyeongbokgung Palace)", which is an important source material for the restoration of the palace, by applying Paltaekron, the geomantic principle of bearings, in order to clarify the building layout principle of Gyeongbokgung Palace. Gyeongbokgung Palace shows the typical geographical conditions that meet the principle of Baesan Imsu (mountain in the back and water in the front) which takes Baegaksan Mountain as the main mountain and the overall layout of the buildings that meet the principle of 'Jeonchak Hugwan (narrow in the front and broad toward inside)' by using the natural topography that meets the principle of 'Jeonjeo Hugo (low in the front and higher toward back).' It is estimated that this layout and arrangement must have been led by geomantic principle of bearings. The analysis of the building layout plan of Gyeongbokgung Palace in the late Joseon Dynasty Period suggests the application of two methods: one is to divide central area from Gwanghwamun Gate to Geoncheongung Hall into eight layers and the other is to apply the bearings of the Eight Trigrams based on the building that becomes the center. As a result, the gate, main hall, and kitchen of all major buildings where the royal family lived are located in the auspicious bearings according to the geomantic principle of bearings while the spaces where people other than the royal family such as those who served the royal family and the officials operated in the palace or the hall that enshrines the ancestors such as Taewonjeong Hall are located in the ominous bearings. Therefore, the buildings of Gyeongbokgung Palace are arranged based on the geomantic principle of bearings.

• Journal of architectural history
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• v.23 no.3
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• pp.35-42
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• 2014

Luoyang Qielanji(洛陽伽藍記) is a document that describes Buddhist Temples in Luoyang, the capital of Northern Wei Dynasty. The purpose of this paper is to analyze the construction backgrounds, architectural elements and layout characteristics of Luoyang Temples in Northern Wei Dynasty. The results are as follows: The construction backgrounds of Luoyang Temples can be categorized into two types: the established-temple (創建型) and the converted-temple(捨宅爲寺型). The layout systems of Luoyang Temples can also be categorized into two main types: The front Pagoda-rear Buddhist Hall layout(前塔後殿), The front Buddhist Hall-rear Lecture Hall layout(前殿後堂). In Luoyang Temples, the pagoda was still an important element of the layout.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1981-1983
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• 1998

The principle of the MHD generation is based on Faraday's law of induction that a eletromotive force(u ${\times}$ B) is generated when the working gas of velocity u flows a channel in which magnetic field of strength(B) exists. In MHD power generation system, enthalpy of the working gas is converted to electric power directly through expansion in generator channel. It means that electric power can be generated without moving mechanical linkage such as turbine blades. There are two types in the MHD generator; linear type Faraday and disk type hall generator. Disk type hall generator is the main target of this paper. Isentropic efficiency and enthalpy extraction rate of disk type shock tube driven hall generator is discussed here.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.602-605
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• 2008

The anode sheath structure in the hollow anode of an anode-layer type Hall thruster was numerically computed using a fully kinetic 2D3V Particle-in-Cell and Direct Simulation Monte Carlo(PIC-DSMC) code. By treating both ions and electrons as particles, anode surface region, which is electrically non-neutral, was analyzed. In order to analyze in detail, the calculation code was parallelized using Message Passing Interface (MPI). The code successfully simulated the discharge current oscillation. In the low magnetic induction case, ion sheath appears in the anode surface because ionization is enough to maintain the plasma occurs in the anode hollow. As the magnetic induction increases, main ionization region move to outside of the anode. At the same time, anode sheath voltage decreases. In the high magnetic induction case, electron sheath appears on the anode surface periodically because the ionization occurs mainly in the discharge channel. This anode sheath condition shift can be explained using the simple sheath model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.2
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• pp.447-453
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• 1999

In MHD power generation system, enthalpy of the working gas is convened to electric power directly through expansion in generator channel. It means that electric power can be generated without a moving mechanical linkage such as turbine blades. The principle of MHD generation is based on Faraday'law of induction that eletromotive force(u$\times$B) is generated when the working gas of velocity u flows a channel in which magnetic field of strength(B) exists. In this paper, helium gas seeded with cesium is used as working gas. There are two types of generator in MHD generation; linear type faraday and disk type hall generator. Rogowski coils having the bandwidth of the 100(Hz) ~ 20(kHz) were used for measuring current flowing MHD disk channel. Optimum load resistor value of the MHD generator studied was 2.5[$\Omega$]. Disk type hall generator's generation performance is the main target of this paper, which superiors to linear type Faraday generator in many points. Isentropic efficiency and enthalpy extraction rate of disk type shock tube driven hall generator is discussed here.

• Journal of The Korean Digital Architecture Interior Association
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• v.9 no.3
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• pp.25-35
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• 2009

This study is planning improvement of welfare facilities about the hall for the aged in apartment housing. An apartment house, famous residential type in Korea, put an important value on its convenience and economical efficiency of furniture arrangement by maximizing floor space index. In this regard, leisure usage of house was not carefully considered for the aged people. To redefine the efficiency of welfare facilities, research mainly deals with analysis of realistic needs for the aged through the spot survey and interview. The main purpose of this study is to enhance the quality of welfare facilities and propose the improved welfare facilities for the aged people. Through the research, conclusions are as followed First, Facility standard and provisions of the law should be revised for considering population growth of the aged people. Second, there are 4 plan types in the hall for the aged. Contrary to our expectation, diversity of program was not found however various program planning is needed for considering its different types of plan. Third, according to regulation, space restriction is based on the number of households. Therefore, room and space standard does not depend on the number of people. From now on, in order to improve quality of welfare facilities of the aged, revision of laws and overall facility standard should be implemented in advance.

• Korean Journal of Heritage: History & Science
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• v.35
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• pp.160-184
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• 2002

The composition analysis of mural pigments at Daeungjeon Hall of Bongjeongsa Temple(Treasure No. 55) and ancient tomb with mural pigments in Goadong(Historic site No. 165) were carried out by XRF and MXRD. The analytical result showed that red pigments were Red Lead($Pb_3O_4$), Cinnabar(HgS) at Daeungjeon Hall of Bongjeongsa Temple and Cinnabar(HgS) in Goadong. The main composition identified in white pigments were Lead Carbonate Hydroxide[$PbCO_3{\cdot}Pb(OH)_2$]. Green pigments were basic copper chloride[Paratacamite $CuCl{\cdot}Cu(OH)_3$], celadonite[$K(Mg,Fe,Al)_2(Si, Al)_4O_{10}(OH)_2$] at Daeungjeon Hall of Bongjeongsa Temple and were basic copper chloride or basic copper carbonate in Goadong. Therefore it proved that mural pigments painted in use the mineral materials.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.1
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• pp.116-121
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• 2019

The LVDT (Linear Variable Displacement Transducer) type sensor used for the existing ship's steering gear is simple on / off that does not perform proportional control operation to the control & unloading device. When the main spool is located at both extremes, It is reflected in the price by using an expensive sensor for import. In this paper, the Hall Effect Sensor is applied to Hydraulic Locking Alarm to analyze classification rules, structure, characteristics and operation principle of valves, and research on localization development in terms of cost reduction. The comparative analysis of the existing prototypes and the cause analysis of the problems were carried out, and the structural analysis showed satisfactory results within the allowable stress range. In addition, it was verified through experiments that the actual operation is realized by applying the actual developed product, and it was confirmed that the load on the maximum value exceeds the allowable maximum load even in the case of the universal tensile test in preparation for the departure of the rod casing.