• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.804-807
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• 2005

In this paper, a double scotch yoke mechanism for moving simultaneously the fixed contact and moving contact of a gas circuit brake, is proposed and designed to improve the breaking characteristics of the circuit breaker. Firstly, the design parameters of the scotch yoke are kinematically determined from the desired design condition of the circuit breaker. Next, the stroke curve of the moving contact is designed by considering the design parameter and the specified opening characteristics of electric contacts. Based on the scotch yoke and stroke curve, the dynamics of the electric contacts is analyzed using ADAMS model of switch mechanism.

• 소성∙가공
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• 제21권8호
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• pp.473-478
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• 2012

The yoke, a component of conventional motor-driven power steering system, often contains welding defects from its manufacturing process. To eliminate these defects, the precision cold forging process has been tried. In this study, the double-action complex forging has been used to manufacture a torsion joint yoke. The backward extrusion proved faster than the forward extrusion in forging of the product. The double-action complex forging process utilized an upper die composed of a punch, a punch guide, a disc spring and a coil spring. The forged material pushes up the punch guide, and then the disc spring and the coil spring balances the backward extrusion force. Consequently, the flow of material was essentially in the forward direction, resulting in a successful forging operation. The forging load of Al 6061-T6 was higher than that of the automotive structural hot rolled plate.

• Journal of Magnetics
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• 제13권4호
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• pp.173-176
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• 2008

In this study, a new kind of instrument for measuring the magnetic shielding effectiveness (MSE) was developed using a double yoke; one a magnetizing yoke and the other a sensing yoke. Using the developed instrument, the MSE could be measured for a steel sheet specimen in the ELF range, where the magnetic permeability contributes to the MSE at low frequencies and eddy currents contributes to the MSE high frequencies with < 0.1 dB reproducibility. The developed measuring method can be applied to quality control in a steel sheet company producing EMI/EMC shielding materials.

• 한국자기학회지
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• 제26권6호
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• pp.206-212
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• 2016

대형 전동기에서 영구자석을 받치는 철제 받침대의 형상은 요크와의 결합력을 결정하는 매우 중요한 요소이다. 대형 전동기에서 받침대의 형상에 따라 요크와의 결합력 차이가 있다. 이 논문에서는 이중 받침대(Double bed)와 단일 받침대(Single bed)의 결합력을 가상공극 법을 통해 계산하여 차이점과 문제점을 제시하고 단일 받침대가 결합력 향상 측면에서 우위에 있음을 보여준다. 또한 받침대의 아래에 홈(Groove) 형상을 새김으로해서 받침대와 요크 간의 결합력이 향상됨을 보인다

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.60-63
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• 2004

BLDC Motor has many advantages but the motor has slots in Stator like as other conventional Motors therefore cannot be eliminated torque ripple which is not acceptable for a special purpose. For high speed and high efficiency and no torque ripple is a Double Cylinder Motor suggested which has a air-gap-winding and rotating yoke with magnet. Because Airgap winding needs no slot and no ironloss is made in rotating yoke. In this paper describes design and construction and theoretical and experimental investigation of a Double Cylinder Motor.

• Structural Engineering and Mechanics
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• 제17권3_4호
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• pp.291-302
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• 2004

In this paper, load monitoring technologies using U-shape Magnetoelastic (EM or ME) sensors have been exploited systemically for the first time. The steel rod to be tested is the Japan 7 mm piano steel rod. The load dependence of the magnetic properties of the piano steel rod was manifested. Two experimental designs of U-shape magnetoelastic sensors were introduced, one with double pick-up concentric coils wound on the rod to be tested, the other with pick-up coil on one yoke foot. The former design is used to derive the correlation of the relative permeability with elastic tension, while the latter is aimed to reflect the stress induced magnetic flux variation along the magnetic circuit. Magnetostatic simulations provide interpretations for the yoke foot sensing technology. Tests with double pick-up coils indicate that under proper working points (primary voltages), the relative permeability varies linearly with the axial load for the Japan 7 mm piano steel rod. Tests with pick-up coil on the yoke foot show that the integrated sensing voltage changes quadratically with the load, and error is more acceptable when the working point is high enough.

• 대한전기학회논문지:전력기술부문A
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• 제54권3호
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• pp.133-138
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• 2005

This paper presents a characteristics of horizontal swing angle in V type suspension string sets for 765kV T/L. The design of V type suspension string set does not differ from that of general string set for general towers, but it prevents instabilities from swing motion by the horizontal angle and by the wind pressure. We were designed specially 6 conductor yoke, arcing horn and earth horn. And we were decided to 550mm for a distance of strings. We were carried out characteristics of horizontal swing test and movement of mass center test for V-string sets of 400kN single, 300kN double and 400kN double. This products will be used for 765kV T/L of 1 circuit in suspension towers.

• 한국자기학회지
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• 제5권4호
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• pp.294-298
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• 1995

A shielded magnetoresistive (SMR) head which has double MR films and linearizes each other has been designed and studied by applying the transmission-line model. We have analyzed the yoke efficiency, bias efficiency and read efficiency of the SMR head. The read efficiency strongly depends on the height of the sensor and slightly on the other geometric parameters. The yoke and bias efficiencies vary with gap length, insulated layer thickness and relative permeability. A quasi-index reduction in the signal flux is observed when the displacement moves away from the medium.

• 조명전기설비학회논문지
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• 제28권2호
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• pp.48-53
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• 2014

The shield effect of 4 layered shield case was investigated in this paper. The material of the case was non-oriented SiFe sheet with a thickness of 0.5mm. The size of the case was 100mm wide, 100mm high and 300mm long. Relative permeability of SiFe sheet was needed to calculate shield effect. It was obtained from the measurement by a ferrite yoke and from the calculation by eddy current FEM analysis. Three configurations were used to connect both ends of SiFe sheet. First one is a connection by double-welded butt. Second one is to put the sheet the same material above the confronted both ends of the sheet to avoid a leakage magnetic flux. The last one is ideally without any connection. The shield effect of the second one agreed well with the last one and showed the shield effect of -40dB.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.709-715
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• 1992

In this study attempts were made to identify the areas of single animal ploughing (SAP) in Bangladesh, causes of its localization and the socio-economic constraints hindering the expansion of the system. To determine the areas of single animal ploughing, 123 upazilas of 15 districts were surveyed. Of them, 16 upazilas were found heavily engaged with this system. A detailed investigation of 469 SAP and 439 double animal ploughing (DAP) farmers revealed that there was significant difference between the two systems in respect of cost of production and yield per unit of land. The benefit/cost (B/C) ratio was higher in SAP system. However, no significant difference was observed in respect of time required for ploughing, intensity of cropping, cost of implements, and cost of repairing implements (except yoke). The study recommends for expansion of SAP system in areas where buffaloes are concentrated. Fro this purpose, logistic and institutional supports need to be made available.