• Journal of Electrical Engineering and Technology
• /
• v.7 no.3
• /
• pp.342-348
• /
• 2012

This paper presents a moving-magnet type linear actuator designed by using flux concentration type permanent magnet arrangement, which can generate higher magnetic flux density in air-gap. In this construction, detent force which is induced by both slot-effect and end-effect becomes larger due to strong attractive forces. To reduce cogging force we have employed a modular mover structure of two magnetic pole sections connected with a center yoke. The improved motor performance is demonstrated with the prototype machine.

• Design & Manufacturing
• /
• v.13 no.1
• /
• pp.55-60
• /
• 2019

Smart-phone in the recently released high-end applied to the camera module is equipped with the most features auto focusing camera module. Also, auto focusing camera module is divided into voice coil motor, encoder, and piezo according to type of motion mechanism. Auto focusing camera module is composed of voice coil motor (VCM) as an actuator and leaf spring as a guide and suspension. VCM actuator is made of magnet, yoke as a metal, and coil as a copper wire. Recently, the assembly as yoke and magnet is made by human resources. These process has a long process time and it is difficult to secure quality. Also, These process is not economical in cost, and productivity is reduced. Therefore, an automatic assembly as yoke and magnet is needed in the present process. In this paper, we have developed an automatic assembly device that can automatically assemble yoke and magnet, and performed verifying performance. Therefore, by using the developed automatic assembly device, it is possible to increase the productivity and reduce the production cost.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.13 no.6
• /
• pp.104-110
• /
• 2014

This paper presents a non-contact inspection system for automatically measuring the thickness of an aircraft wing rip product. In order to conduct the inspection of the wing rib thickness automatically, a non-contact laser displacement sensor, end-effector, and a robot were selected for use. The non-contact type inspection system was evaluated by measuring the measurement deviation of the rotation direction of a C-type yoke end-effector and the transfer direction of a V-slim end-effector. In addition, the non-contact inspection system for wing rib thickness measurements was validated through thickness measurements of a web, flange, and stiffener.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.22 no.4
• /
• pp.121-129
• /
• 2008

This paper deals with the design of BLDC motor replacing ferrite magnet with rare earth magnet. Electric machinery system using ferrite magnet motor is already widespread in large numbers. Electrical appliance makers have a tendency to adhere to existing system using ferrite magnet motors because of redesigning the whole system. This paper designs the rare earth magnet motor untouching the external system dimension and motor outer size. To do the design simply, finite element package is used iteratively To reduce the cogging torque effect and magnetic saturation, stator yoke shape and the groove of the end face of yoke are redesigned.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.49 no.5
• /
• pp.291-296
• /
• 2000

Recently large size color TV and computer monitor are very popular and a lot techniques are being developed to get a high quality picture on the screen through reducing the convergence error among the red, green and blue beams and achieving a high focusing. One of the techniques is considering the mutual effects of the components of the Brown tube. The magnetic deflection yoke, especially, stands immediately next to the electron gun and generates the leakage magnetic fields at the electron gun which affects the trajectories of the electron beams inside the gun. Hence a shield cup made of thin conducting plate is located at the end of electron gun in order to shield the leakage flux from the deflection yoke. Since the red, green and blue beams are placed unsymmetrically the shielding effects of the shield cup on the beams are not same and eddy current controller, made of thin conducting plate, is auxiliary placed inside the shield cup. In this paper a transient magnetic field analysis algorithm is developed using boundary element method, and applied to the analysis of the shielding effects of the eddy current controller of shield cup in an electron gun.

• Journal of Hospice and Palliative Care
• /
• v.25 no.3
• /
• pp.133-137
• /
• 2022

A 72-year-old woman with metastatic lung cancer to bone and brain and with left external iliac vein thrombosis was under the care of a community palliative care provider. She experienced an acute pain crisis due to acute limb ischemia of the left lower limb. Goals-of-care discussions were held with the patient and her family; she prioritized symptom control and end-of-life care at home. The family and patient were aware of her short prognosis. Her complex pain was managed by the community palliative team, and her family was empowered to give subcutaneous injections. We illustrate a case showing the importance of community health services with palliative care support in providing symptom management and support to patient and family caregivers throughout the course of a life-limiting illness. It also highlights family caregivers' potential psychological distress in delivering subcutaneous injections in terminal care for a patient at home.

• Progress in Superconductivity and Cryogenics
• /
• v.12 no.2
• /
• pp.13-16
• /
• 2010

The superconducting synchronous motor or generator mostly has high permeability iron only around outer yoke portion. Therefore, if excitation voltage (Back E.M.F) is calculated from 2 dimensional magnetic field distributions, it can be largely different from actual value due to additional voltage originated from end coils. In order to calculate the excitation voltage more accurately, 3 dimensional magnetic field calculation is necessary for including the end coil effect from large air-gap structure. The excitation voltage can be calculated by stator (armature) coil linkage flux originated from rotor (field) coil excitation, but it is difficult to calculate the flux linkage exactly because of complicated structure of the stator coil. This paper shows a method to calculate the excitation voltage from 3 dimensional magnetic energy that can be calculated directly from volume integration of magnetic flux density and field intensity scalar product through FEM (Finite Element Method) analysis software.

• Tribology and Lubricants
• /
• v.29 no.6
• /
• pp.397-402
• /
• 2013

This study examined the tribological characteristics of the drive shaft and axle system in vehicles. The first drive shaft example contained end play for a CV joint that transferred part of the transmission power to the wheel. The joint part of the drive shaft was deformed because of reduced durability due to wear. Thus, vibrations caused the body to shake and become unbalanced when the drive shaft transferred the power. The second example was the cross-section of a shaft that connected the slip-connection of the propeller shaft on the input side to the yoke flange of the output side; the durability was reduced because of corrosion. End play caused by wear between the bearing and cross-section shaft appeared to cause shaking. In the third example, a grease leak reduced lubrication and thus caused damage to the hub bearing and inside the knuckle. The failure was produced by sticking. The fourth example had noise produced by the gear and gear transfer. This was due to the backlash of the pinion and few ring gears for the differential gear. Therefore, drive shaft and axle systems must be thoroughly checked and managed to minimize and reduce failure phenomena.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.760-761
• /
• 2008

This paper deals with the core loss as well as torque characteristics according to the change of stator shape in an interior permanent magnet synchronous motor (IPMSM). The finite element method and functional core loss data obtained by the steinmetz equation are used in order to estimate the core loss. To minimize the core loss caused by the shape of tooth tip, slot-area and volume of permanent magnet, those are all the same in each model. In the end, the ratio between tooth width and yoke thickness to minimize the core loss in the IPMSM is presented in this paper.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.17 no.2
• /
• pp.223-237
• /
• 2015

This study is to compare the pattern making methods of men's jeans and to analyze sizes of parts while also evaluating the appearance and fit according to a 3D virtual garment simulation. Five types of patterns are selected for the analysis. For the appearance evaluation, the study conducted a virtual clothing simulation, created a perspective drawing, and applied Clothing pressure to each test outfit. First, according to the pattern comparisons, A and D had the shortest crotch length, while B had the longest; B had the narrowest crotch width, while C had the widest; C had the greatest waist circumference, and B had the smallest; C had the greatest knee and hem circumference, while E had the smallest. Second, according to the appearance evaluation, E pants had the highest rating overall for the waist, crotch, knee, and hem comfort; A pants had the highest rating for the yoke line end and placement; and C pants had the highest rating for the side seam line. According to the correlation analysis, ease of the waist, hips, hem and thighs were important factors (in that order) in determining the overall appearance of the jean pants.