• 한국치위생학회지
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• 제14권2호
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• pp.223-230
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• 2014

Objectives : The purpose of the study is to develop a program of oral health education by investigating the use and educational needs on auxiliary oral care products in employees. Methods : A self-administered questionnaire was filled out by 321 employees in the heavy industry in Youngam-gun. Results : Most of the employees used the dental floss. Approximately 72.6% answered that they did not receive the education on auxiliary oral care products and 81.3% of subjects did not participate in the education for the auxiliary oral care products. If free education is provided, 66.5% would receive the auxiliary oral care products use education. The best ways of education were expert lecture and brochure. Conclusions : The employees want the continuing education for the use of auxiliary oral care products. The oral health promotion program must be focused on the active practice of oral health behavior.

• International Journal of Railway
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• 제8권1호
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• pp.10-14
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• 2015

Due to the characteristics of the vehicle structure, the magnetic levitation train has a confined bottom space thus a study on miniaturization and weight reduction of auxiliary power unit is essential. This auxiliary power unit is an essential device used for illumination, air conditioning, heating and air brake equipment excluding the motor. The previous auxiliary power unit for magnetic levitation train has used the hard switching having a high switching frequency with heavy loss in order to reduce the size of filter reactor and transformer but the reduction in volume was not significant. In this paper, by reducing the loss, reducing the size of the cooling unit and by increasing the switching frequency using the soft switching of resonant converter, it has miniaturized and reduced the weight of filter reactor and transformer which occupy significant space in the auxiliary power unit. This study has verified the performance of 50KVA grade prototype through simulated interpretation and analysis, and compared the size and weight of auxiliary power unit of the previous magnetic levitation train.

• 해양환경안전학회지
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• 제21권6호
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• pp.759-769
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• 2015

본 논문에서는 12펄스 정류기의 커패시터 중앙 DC버스에 개선된 보조전원장치를 설치하는 방법을 제안하였다. 11차 및 13차 고조파가 감소하는 이론적인 배경을 다루었으며 부하전류의 크기, 전원전압의 위상 및 크기, 커패시터 전압에 따라 개선된 보조전원의 파형 및 크기가 어떻게 제어되어야 하는지를 제시하였다. 기존의 구형파 보조전원장치를 적용한 경우는 전 영역에서 고조파 왜형률이 6~60[%]로 큰 편차를 보이지만 본 눈문에서 제안하는 개선된 보조전원장치를 적용한 경우 저 부하에서 고 부하에 이르는 전 영역에서 57~71[%] 라는 안정되고 뛰어난 고조파 왜형율 저감 효과를 보인다. 특히 10[%] 부하상태에서 기존방식은 고조파 왜형율 저감 효과가 6[%]로 효과가 거의 없지만 제안된 방식은 71[%]라는 놀라운 저감성능을 보여주고 있다. 소프트웨어 PSIM을 활용하여 컴퓨터 시뮬레이션을 통해 제안된 방식의 유효성을 입증하였다.

• Journal of Magnetics
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• 제21권2호
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• pp.298-302
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• 2016

In bone density examinations, a change in the measured BMD occurs owing to the differences between the measured areas. To address this problem, we aimed to develop a new auxiliary device that could be rotated by $15^{\circ}$ by fixing the ankle to the distal femur neck. Dual energy X-ray absorptiometry (DXA) of BMD examinations were performed once a year, but 10 patients were examined over three sessions to analyze the area for measuring the femur neck BMD. The goal of this test was to determine the device's reliability, and the results were expressed in terms of the standard deviation of measurements. After performing bone density measurements using the new auxiliary device on 10 normal patients, with three measurements for each patient, the obtained standard deviation was 0.03. The standard deviation of the measured BMD was 0.19 when using the currently existing auxiliary device, while the standard deviation of the measured BMD was 0.03 when using the new auxiliary device. By using the new auxiliary device, the standard deviation could be reduced by ~80%. Accurate rotation of the femur neck was possible in all examinations, and the standard deviation of BMD measurements could be reduced by up to 80% compared with the measurements performed using the currently existing auxiliary device. We hope that this advantageous new design can be used as a standard auxiliary device for measuring the femur neck BMD.

• 대한방사선기술학회지:방사선기술과학
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• 제46권6호
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• pp.485-491
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• 2023

As an auxiliary tool for fixing the patient's posture when taking an X-ray, sponges with high radiolucencies are laminated in various thicknesses. This study aimed to evaluate the usefulness of an auxiliary tool for hand oblique projection X-ray by manufacturing it with a uniform thickness by 3D printing and comparing it with existing sponge tools. In the auxiliary tool, radiolucency was measured at the stairs where each finger was located, and pixel information values were compared in the digital imaging and communications in medicine(DICOM) image. Contrast to noise ratio(CNR) and signal to noise ratio(SNR) were compared by shooting the hand phantom and the auxiliary tool together. As the thickness of the sponge tool increased, radiolucency decreased by 15.52% and pixel information value increased by 20.61%. The transmittance of the 3D printing tool increased by 0.82%, and the pixel information value differed by 5.66%. CNR and SNR increased by 20.03% and 22.42% in 3D printing compared to existing sponge tools. while taking hand oblique projection, maintaining the thickness of the auxiliary tool uniformly through 3D printing maintains high radiolucency and minimal impact on medical images, and increases CNR and SNR, making it useful as an auxiliary tool for taking hand oblique projection.

• Journal of Electrical Engineering and Technology
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• 제1권4호
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• pp.455-460
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• 2006

This paper presents the convergency property of the Auxiliary Problem Principle when it is applied to large-scale Optimal Power Flow problems with Distributed or Parallel computation features. The key features and factors affecting the convergence ratio and solution stability of APP are also analyzed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.534-546
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• 2002

The electrical interfaces among the components comprising the auxiliary power systems and their electrical interface with other train-borne systems are described. As such, this standard treats the auxiliary power system compononents as black boxes and addresses only their interface requirements.

• 한국안전학회지
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• 제27권4호
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• pp.33-37
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• 2012

This paper describes the characteristics for ground impedance of counterpoise according to position of auxiliary probe and frequency using the fall-of-potential method and the testing techniques to minimize the measuring errors are proposed. The fall-of-potential method is theoretically based on the potential and current measuring principle and the measuring error is primarily caused by the position of auxiliary probes. In order to analyze the effects of ground impedance due to the distance of the current probe and frequency, ground impedances were measured in case that the distance of current probe was located from 10[m] to 100[m] and the measuring frequency was ranged in 55 [Hz], 128[Hz], 342[Hz], and 513[Hz]. The results could be help to determine the position of auxiliary probe when the ground impedance was measured at grounding system.

• 전력전자학회논문지
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• 제18권6호
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• pp.547-555
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• 2013

This paper proposes the interleaved buck converter using a soft switching auxiliary circuit. In this scheme, an auxiliary circuit is added to the conventional interleaved buck converter and used to achieve soft-switching conditions for both the main switch and freewheeling diode. In addition, the switch in the auxiliary circuit operates under soft-switching conditions. Also, according to the input to output conditions, the main switch achieved zero-current-transition(ZCT) or zero-current & zero-voltage-transition(ZCZVT) at turn on. Thus, the proposed interleaved buck converter provides a higher efficiency. The basic operations, in this paper, are discussed and design guidelines are presented. The usefulness of the proposed converter is verified on a 200kHz, 180W prototype converter.

• 조명전기설비학회논문지
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• 제22권7호
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• pp.22-27
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• 2008

A new excitation strategy for a Switched Reluctance Motor with Auxiliary Winding(SRMAW) is described and tested. The proposed scheme has auxiliary winding with one diode which is wound over all poles in one winding. In this scheme, auxiliary winding is used to reduce magnetic stress during commutations. The abrupt change of a phase excitation produces mechanical stresses resulting in vibration and noise. The acoustic noise is reduced remarkably through the 2-stage commutation. The operational principle and a characteristic comparison of the conventional SRM show that this scheme has some advantages including noise reduction as well as high drive efficiency.