• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
• /
• pp.11-16
• /
• 2001

Recent publications showed that a pair of neighboring printed circuit board (PCB) windings can be used as a contactless energy transfer device. As a continued study on this area, the current paper presents the modeling, analysis, and application of the neighboring PCB windings with an emphasis on their circuit properties and device characteristics as a contactless energy transfer device. Theoretical results of the paper are confirmed with experiments on a prototype contactless energy transfer circuit that delivers 24W output power at $68\%$ efficiency through two 35mm-diameter PCB windings separated each other by 2.4mm.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2004년도 추계학술대회 논문집
• /
• pp.1021-1024
• /
• 2004

During demonstrations of a process conditioning spent nuclear fuels, it may be necessary to transport modularized parts of process equipment out of a hot cell because of modules' failure or completion of demonstrations. It may be not easy to transport modules because modules will be contaminated. For this purpose, we have developed a prototype of a device transporting radioactive contaminated materials. We have analyzed conditions of a hot cell and requirements of the device, designed and manufactured a scaled-down prototype of the device, and done some performance tests such as running on the rail, running on the flat floor, and carrying capability of a sliding upper part. From the tests, it has been shown that running on the rail and floor was smooth but the sliding part was deflected if the sliding distance was long. These result will be reflected to a design of the improved transporting device which will be used during demonstrations.

• 동력기계공학회지
• /
• 제20권3호
• /
• pp.64-73
• /
• 2016

In this research work, an algorithm development on tracking end-point of aerial work platform with jib profile and bend-linked boom was carried out to find the X, Y and Z direction value using coordinate transformation matrix. This matrix consists of device status value(length and angle) based on camera position axis, which are sent from device controller PLUS+1 by CAN protocol. These values are used to measure the distance and angle from the camera to the end-point. Using these distance and angle value, monitoring system controls FAN/TILT/ZOOM status of camera to get an adequate scene of workplace. This program was written in Java, C# and C for mobile device. These results provide the information to the aerial work device for secure operation.

• 전기학회논문지P
• /
• 제54권2호
• /
• pp.101-107
• /
• 2005

The reduced power quality due to some of disturbances on power system has great influence on the efficient and life of load for bad with serious economic loss. The response of load about disturbance needs to analysis quantitatively in detail to improve load characteristics. In this research, a power supply device is developed to supply disturbed power similar to that of power system. The developed device can output a voltage and frequency from 180[V] to 240[V], 55[Hz] to 65[Hz] respectively. The most outstanding feature of this device is a function to be performed steady and dynamic state characteristic experiment on load or appliances. Also, this device is designed to include high accuracy ouput and simple measurement.

• Journal of Power Electronics
• /
• 제9권1호
• /
• pp.36-42
• /
• 2009

This paper presents a review of an improved high power-high frequency III-V wide bandgap (WBG) semiconductor device, Gallium Nitride (GaN). The device offers better efficiency and thermal management with higher switching frequency. By having higher blocking voltage, GaN can be used for high voltage applications. In addition, the weight and size of passive components on the printed circuit board can be reduced substantially when operating at high frequency. With proper management of thermal and gate drive design, the GaN power converter is expected to generate higher power density with lower stress compared to its counterparts, Silicon (Si) devices. The main contribution of this work is to provide additional information to young researchers in exploring new approaches based on the device's capability and characteristics in applications using the GaN power converter design.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.120-122
• /
• 2004

Wearable input device that can make free-space typewriting possible is introduced. We named this device as $SCURRY^{TM}$. To measure the angular velocity of hand and the acceleration rates at the ends of fingers, we buried MEMS inertial sensors in this keyboard. We processed sensor signals to get the information on hand movement and finger-click motion. With this signal processing, apparent finger movements were depicted over the virtual keyboard shown on output device of a target computing system. In this paper, a finger-click recognition method is proposed to improve the recognition performance for finger clicking of $SCURRY^{TM}$. The proposed method is composed of three parts including feature extraction part, valid click part, and cross-talk avoidance part. The experiments were conducted to verify the effectiveness and efficiency of the proposed algorithms.

• 한국정밀공학회지
• /
• 제15권11호
• /
• pp.199-207
• /
• 1998

This paper presents the design and the control of three degree-of-freedom(DOF) fine positioning device based on an electro-magnetic force. The device is designed by use of a magnetic circuit theory and it is capable of fine motion due to the electro-magnetic force. The device consists of permanent magnets, yokes and coils. The magnetic fluxes generated from the permanent magnets constitute magnetic paths through steel, whereas the coils are arranged into the gap between two surfaces of the yokes. Therefore, by supplying current to the coils, the coils are capable of some motions due to Lorentz forces. For the optimal design of the actuating system, the system parameters are defined and investigated under the given constraints. From the system modeling in small displacement, three decoupled equations of motion are obtained. To get better performance of the system, a PID controller is implemented. Experimental results are presented in terms of time response and accuracy.

• 한국염색가공학회지
• /
• 제25권1호
• /
• pp.65-69
• /
• 2013

PET fabrics of various luster, fiber thickness(denier), and weaving structure were dyed at the same conditions and determined their grey scale by using naked eyes, computer color matching (CCM) system, and real industry color (RIC) device to evaluate the effectiveness of RIC device developed in this study. As for the luster of fabrics, bright PET showed more differences when compared with semi-dull and full-dull. PET in both naked eyes and RIC device since the RIC device provide the real image of fabrics to observers. As for the fiber thickness, the results of naked eyes and RIC device were very similar while the result of CCM showed lower color grade. Finally, as for the weaving structures of PET fabrics, all the test results by naked eyes, CCM, and RIC device showed almost same grey scales. In these regards, the RIC device developed in this study was comparable to naked eyes by providing the real image of fabrics, however it was difficult to compare the very bright colors such as yellow and fiber thickness(denier) and weaving structure of fabrics.

• 대한전자공학회논문지TC
• /
• 제47권7호
• /
• pp.72-79
• /
• 2010

셀룰러 네트워크 내에서 cellular 링크와 무선 자원을 공유하는 device-to-device(D2D) 링크는 자신이 속한 셀룰러 네트워크에 심각한 간섭을 줄 가능성이 높기 때문에 그것을 방지하기 위해서는 무선 자원 할당의 최적화가 중요하다. 본 논문에서는 D2D 링크가 자신의 간섭을 최소화하면서 효율적으로 cellular 링크와 공존하기 위해서 subset reuse 방법을 기반으로 하는 자원 할당 기법에 대해 제안한다. Cellular 링크와 D2D 링크 주파수 자원 할당의 효율성을 높이기 위하여 셀 상황에 따라 가변적인 subset 크기를 가지는 group-wise subset reuse 방법을 제안한다. 또한, cellular 링크가 같은 주파수 대역을 사용하는 D2D 전송에 의해 간섭을 받는 경우, D2D 링크의 power를 최적화하여 cellular 링크로의 간섭을 최소화하게 된다. 컴퓨터 시뮬레이션 결과를 통하여 link SINR에서 성능 이득을 가지며, local traffic이 증가할수록 전체 cell throughput이 높아짐을 보였다.

• 한국운동역학회지
• /
• 제25권3호
• /
• pp.353-361
• /
• 2015

Objective : The aim of this study was to develop the non-powered horse riding device and was to evaluate the elaborate its applicability throughout static structural and transient structural analysis of the outdoor core strength exercise equipment. Method : Fifteen college students (mass: $69.55{\pm}13.38kg$, height: $1.69{\pm}5.61m$, age: $21.42{\pm}1.83yrs$) rode the powered horse riding device and 14 college students (mass: $71.12{\pm}9.74kg$, height: $1.73{\pm}3.31m$, age: $22.50{\pm}1.47yrs$) rode the non-powered horse riding device for the comparison. All motion capture data was collected at 100 Hz using six infrared cameras and the muscular activities were collected using a Delsys Trigno wireless system. The peak forward/backward lean angle, range of motion anter/posterior and vertical COM(Center of mass) movement of trunk and pelvis segment, and muscle activities of six muscles were compared between the two devices by using independent t-test (p<.05). Results : Several kinematic variables (peak forward-backward lean angle and vertical COM movement of trunk and pelvis segment, range of motion of trunk) significantly different between non-powered and powered horse riding device. The muscle activities of Rectus abdominis and External oblique of abdomen on the non-powered horse riding device were significantly greater than those of the powered device. Conclusion : It was concluded that non-power horse riding device could give the effect of core strength exercise as well as the body motion which can simulate the powered horse riding device.