• 패션비즈니스
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• 제27권2호
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• pp.39-51
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• 2023

The purpose of this study was to effectively improve the thigh muscles of adult women working from home due to COVID-19. In this study, ten adult women working from home performed 1) an electromyography test, 2) a static balance test on a balance board, and a 3) dynamic balance test by squatting on a Bosu ball four times: before electric muscle stimulation (EMS), after EMS, after high-intensity circuit training (HICT), and after EMS plus HICT. For this test, EMS was attached to a medical knee support to manufacture an EMS knee band that could be easily worn regardless of the location. For the experiment, EMS(electric muscle stimulation) was attached to the medical knee protector to manufacture an EMS knee band that can be easily worn regardless of location, and was measured based on the right foot. The study results confirmed that in all tests (electromyography test, static balance test on the balance board, and dynamic balance test by squatting on a Bosu ball), thigh strength improved in the order of treatment before EMS, after EMS, after HICT, and after EMS plus HICT. The study showed that people working from home or with activity restrictions due to COVID-19 had better exercise effects when wearing the EMS knee band and performing HICT, even in a small space.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.265-269
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• 1996

In this paper, electric field interference was analyzed in the Printed Circuit Board to restrain the elcctromagnetic wave using Boundary Element Method and Finite Element Method. First, charge density distribution was simulated using Boundary Element Method and the characteristic impedance was caculated to restrain the reflex wave, and mutual capacitance was caculated in the multi-strip line PCB. Finally, electric field was simulated in the variable patterns using Finite Element Method. As a result, the optimal structure and characteristics of strip line was obtained and the imformations about the optimal design pattern could be obtained with the analysing the feild distribution.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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• pp.80-83
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• 2004

Previously, in order to send information from the local controller to the display board, the hardware or software had to be handled and run through 3-phases, which include the PC-card or PC-add Board, I-F card and Sub board. This study will attempt to design a board that handles information by connecting the USB port of the PC directly to the Sub board. In addition, an MPU will be attached to the previously complex hardware circuit to design a software drive engine module, which allows for the development of new products by modifying only the software engine and not the hardware.

• 한국안전학회지
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• 제33권5호
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• pp.21-27
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• 2018

The purpose of this study is to develop a SOP (Standard Operating Procedure) for a distribution board that can monitor the leakage current of a load distribution line in real time. The developed distribution board was fabricated by applying IEC 61439-1. It consists of the distribution board and an alarm device. The work process for making the distribution board was compliant with the KEMC (Korea Electrical Manufacturers Cooperative) regulations. And the AC distribution board range is 1,000 V. In addition, the voltage in DC is less than 1500 V. The distribution board receives a 3-phases and 4-wires power supply system and can supply power to the load of a maximum of 32 single or three phase distribution circuits. Also, leakage current measured on the power distribution board was used by sensors installed. The SOP of the developed distribution board consists of the installation standards for the short circuit alarm device and sensor, the surge protection device, switches and indication lamps, and other devices. The operation procedure was prepared so that each manufacturing step of the distribution board must be confirmed by the persons in charge of preparation, production, quality control and approval before moving forward to the next step.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.321-322
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• 2015

The aim of this paper is to propose a design method for the double-sided LCC compensation circuit for 6.6kW electric vehicle (EVs) wireless charger. The analysis and comparison with several compensation topologies such as SS, SP, PS, PP and the hybrid LCC compensation is presented. It has been found that the hybrid LCC compensation has superior performance in comparison with other topologies. The design procedure for the EV charger is presented and the PSIM simulation results are provided.

• 한국자동차공학회논문집
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• 제16권1호
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• pp.1-7
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• 2008

This paper presents electromagnetic interference(EMI) suppression method applied on the direct current(DC) motor driver for power tail gate control. EMI noise is generated by the fast switching of power devices connected to electric loads. It has become a matter of concern because of the vast increase in the number and sophistication of electronic system in automotive environment. The proposed EMI reduction method is based on the principle of reducing the transient speed of power devices by changing the parameters of the driver circuit related to the power MOSFET. In this paper, power losses were calculated by loss equations and thermal simulation was used to evaluate the effect on printed circuit board. Based on these results, the DC motor driver was fabricated and tested. The proposed method can help to design a DC motor driver which allows it to obtain an acceptable compromise between power losses and EMI.

• 한국전자통신학회논문지
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• 제14권3호
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• pp.529-536
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• 2019

스마트 센서 시스템에 압전 에너지 하베스터를 적용하기 위해서는 AC-DC 정류기를 비롯한 에너지 하베스트 인터페이스 회로가 필수적이다. 본 논문에서는 기본적인 회로인 Full Bridge Rectifier(: FBR) 회로와 동기식 압전 에너지 하베스트 인터페이스 회로의 성능을 보드레벨 시뮬레이션으로 비교하였다. 그 결과, 동기식 압전 에너지 하베스트 인터페이스 회로 중 하나인 Synchronous Electric Charge Extraction(: SECE) 회로가 FBR에 비해 출력 전력이 약 4 배 이상 더 컸고, 부하 변동에도 변화가 거의 없었다. 그리고, 출력 전압이 40V 이상인 압전 에너지 하베스터용 SECE 회로에 필수적인 고전압 비교기를 0.35 um BCD 공정으로 설계하였다. 설계한 고전압 비교기를 적용한 SECE 회로는 출력 전력이 FBR 회로 보다 427 % 향상됨을 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1506-1508
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• 2005

VCO(voltage controlled oscillator) using mobile communication device decides direct characteristics as parts that affect important in stable oscillation and distortion characteristics of system. VCO used 900 MHz band was designed by the transformation of Colpitts circuit form use ADS that consider Q-factor to minimize phase noise. VCO manufactured together evaluation board and voltage control oscillator to FR-4 PCB. VCO experimented chracteristics after control through resonance department tuning. In our research, the designed VCO has 15.5 dBm output level at the bias condition of 6V and 10mA and the operating frequency range of 917 MHz$\sim$937 MHz band. Phase noise is -98.28 dBc/Hz at 1 MHz frequency offset from the carrier.

• 한국정보통신학회논문지
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• 제13권4호
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• pp.737-746
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• 2009

본 연구에서는 정보가전기기에서 과부하를 방지하고 이상신호를 검출하며 화재방지를 제어할 수 있는 원 칩(one chip) 시스템 IC를 개발하였다. 이를 위하여 화재에 직접적으로 영향을 미치는 아크(arc) 검출회로와 감전을 방지하기 위한 누전검출회로를 설계하였다. 시뮬레이션과 표준트랜지스터를 이용한 bread boarding 평가에 의해 블록별로 설계된 회로를 검증하였다. 평가결과로부터 34 V 2 Metal $1.5{\mu}m$바이폴라 트랜지스터 공정을 이용하여 시스템 IC를 제작하였다. 제작된 시스템 IC와 IC응용회로를 PCB보드에 실장하여 화재방지 시스템보드의 전기적 성능을 평가하였으며, 아크와 GF(ground fault) 신호에 잘 동작함을 확인하였다.

• 한국표면공학회지
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• 제55권5호
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• pp.299-307
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• 2022

Gold plating is used as a coating of connector in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. In most cases, internal connection between device and package and external terminals for connecting packaging and printed circuit board are electroless Ni-P plating followed by immersion Au plating (ENIG) to ensure connection reliability. The deposition behavior and film properties of electroless Au plating are affected by P content, grain size and mixed impurity components in the electroless Ni-P alloy film used as the underlayer plating. In this study, the correlation between electroless nickel plating used as a underlayer layer and cyanide-free electroless Au plating using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent was investigated.