• 한국산업융합학회 논문집
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• 제26권5호
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• pp.813-823
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• 2023

In this study, microstructure, hardening layer hardness, and case depth were evaluated after induction hardening(IH) of base metal specimen(BM) treated with annealing and quenching-tempering specimen(QT) treated with quenching and tempering. The microstructure after IH was significantly influenced by the microstructure before IH and the induction coil heating movement speed, but the effect of the induction frequency was very small. The hardness of the hardened layer at an induction coil heating movement speed of 15 mm/s or less was more influenced by the microstructure before IH than the induction coil travel speed and induction frequency. The induction coil travel speed has the significantly effect on the case depth, the induction frequency has effect and the microstructure before IH has a small effect.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.117-119
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• 1994

While the projectile in the induction type coil guns is in motion, there exists an induced current in the sleeve coils of the projectile. The motion includes not only the z-axial movement but transversal movement. The projectile in coil guns, which is not supported physically, gets a force in the transversal axis to have a motion in this axis. As a result of this motion, sleeve effects are exhibited to the projectile. This paper presents the analysis of the secondary effect especially due to the propelling velocity of the projectile.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.1007-1012
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• 2002

In this paper, a regeneration inverter is proposed using 3-level inverter. Electric regeneration means regeneration brake in electric railway vehicles. Induction motors, generally used with railway vehicles, convert the electric energy to the movement energy when vehicle is running. When the vehicle stop, the induction motor convert the movement energy to the electric energy. Usually, this energy is used with another running vehicle in the same section. If there is no vehicle around when the regeneration is occurred, regeneration energy is consumed by heat energy with resistors. The proposed inverter is capable of reuse this regeneration energy in another place.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1060-1062
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• 1993

This paper presents the dynamic analysis method of a linear induction motor by finite element method. For simulation of dynamic performance, a step by step process with respect to time is used with external voltage source and motional equation. Movement is taken into account by a combination of mesh distortion and remeshing technique.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제3B권3호
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• pp.122-127
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• 2003

This paper presents a new time-stepping 3-D analysis method coupled with an external circuit with motion equation for dynamic transient analysis of induction machines. In this method, the magneto-motive force (MMF) generated by induced current is modeled as a passive source in the magnetic equivalent network. So, by using only scalar potential at each node, the method is able to analyze induction machines with faster computation time and less memory requirement than conventional numerical methods. Also, this method is capable of modeling the movement of the mover without the need for re-meshing and analyzing the time harmonics for dynamic characteristics. From comparisons between the results of the analysis and the experiments, it is verified that the proposed method is capable of estimating the torque, harmonic field, etc. as a function of time with superior accuracy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.53-55
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• 1995

This paper presents the characteristics of linear induction motors fed by a voltage source PWM inverter. In the calculation, 2D finite element method is used considering the movement by moving mesh. Integro-differential approach is adopted for the copper loss calculation considering the skin effect.

• 한국산학기술학회논문지
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• 제10권4호
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• pp.740-746
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• 2009

본 논문에서는 공진형 유도가열기를 이용한 2단 직렬 부하형 유도가열 과열증기 발생장치를 제안하였다. 발열방식은 외부의 가열코일로부터 특수 합금 발열체에 비접촉 상태로 전자유도 와전류를 구조체에 흐르게 하였다. 인버터는 풀-브리지 고주파 직렬 부하 공진형 이며, LC 공진 설계에서 부하자체를 인덕터로 선정하여 효율을 최대화 하였다. 개발된 장치는 전자유도가열 발열체와 유체이동에 의한 새로운 열교환 방식으로 일체의 연소과정 없이 기체, 액체 및 증발체 등을 상온에서 고온에 이르기까지 고정도의 가열이 가능하다.

• 대한치과교정학회지
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• 제47권3호
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• pp.158-166
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• 2017

Objective: To investigate how bracket slot size affects the direction of maxillary anterior tooth movement when en-masse retraction is performed in sliding mechanics using an induction-heating typodont simulation system. Methods: An induction-heating typodont simulation system was designed based on the Calorific Machine system. The typodont included metal anterior and resin posterior teeth embedded in a sticky wax arch. Three bracket slot groups (0.018, 0.020, and 0.022 inch [in]) were tested. A retraction force of 250 g was applied in the posterior-superior direction. Results: In the anteroposterior direction, the cusp tip of the canine in the 0.020-in slot group moved more distally than in the 0.018-in slot group. In the vertical direction, all six anterior teeth were intruded in the 0.018-in slot group and extruded in the 0.020- and 0.022-in slot groups. The lateral incisor was significantly extruded in the 0.020- and 0.022-in slot groups. Significant differences in the crown linguoversion were found between the 0.018- and 0.020-in slot groups and 0.018- and 0.022-in slot groups for the central incisor and between the 0.018- and 0.022-in slot groups and 0.020- and 0.022-in slot groups for the canine. In the 0.018-in slot group, all anterior teeth showed crown mesial angulation. Significant differences were found between the 0.018- and 0.022-in slot groups for the lateral incisor and between the 0.018- and 0.020-in slot groups and 0.018- and 0.022-in slot groups for the canine. Conclusions: Use of 0.018-in slot brackets was effective for preventing extrusion and crown linguoversion of anterior teeth in sliding mechanics.

• The Plant Pathology Journal
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• 제33권1호
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• pp.53-65
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• 2017

Barley yellow dwarf virus (BYDV) belongs to Luteovirus and is limited only at phloem related tissues. An open reading frame (ORF) 4 of BYDV codes for the movement protein (MP) of BYDV gating plasmodesmata (PD) to facilitate virus movement. Like other Luteoviruses, ORF 4 of BYDV is embedded in the ORF3 but expressed from the different reading frame in leaky scanning manner. Although MP is a very important protein for systemic infection of BYDV, there was a little information. In this study, MP was characterized in terms of subcellular localization and programmed cell death (PCD). Gene of MP or its mutant (ΔMP) was expressed by Agroinfiltration method. MP was clearly localized at the nucleus and the PD, but ΔMP which was deleted distal N-terminus of MP showed no localization to PD exhibited the different target with original MP. In addition to PD localization, MP appeared associated with small granules in cytoplasm whereas ΔMP did not. MP associated with PD and small granules induced PCD, but ΔMP showed no association with PD and small granules did not exhibit PCD. Based on this study, the distal N-terminal region within MP is seemingly responsible for the localization of PD and the induction small granules and PCD induction. These results suggest that subcellular localization of BYDV MP may modulate the PCD in Nicotiana benthamiana.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.65-67
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• 1995

The squirrel cage rotors for induction motors may have several faults such as broken bars, bad spots in end ring, abnormal skew caused by improper processing. These faults have bad effect on the performance of the induction motor. This paper proposes the detecting technique of these faults by analyzing the current of the detecting electric magnet, using 2-D finite element method taking account of the rotor movement.