• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.158-164
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• 2018

The purpose of this study is to statistically analyze the signal intensity pattern according distance from the surface coil center and to maintain optimal signal intensity under clinical circumstances where the surface coil centers are not correctly positioned due to various causes. The cylindrical fluid phantom was placed and moved from the coil center in vertical direction with 1 cm increments. The signal intensities were measured and compared. As a result, the signal intensity showed no significant difference within 4 cm and 1 cm from in T1 weighted images while in T2 weighted images the signal intensity was maintained up to 5 cm and lower 3 cm in the upper and lower direction from the coil center. In conclusion, to maintain the optimal signal intensity the target region should be located within the reference distances proposed in this study.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.603-611
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• 2008

In this paper, we introduce a multi-coil antenna which is useful for reducing the effects of radio frequency noise in an inductively coupled RFID system. A multi-coil antenna is composed of a central coil and four subsidiary coils that are connected in series. A multi-coil antenna is designed so that the total noise disappear when the induced voltages of a central coil and subsidiary coils are added. The noise in a multi-coil antenna was about 30 dB lower than that in a single coil antenna. The multi-coil antenna is very effective in noise reduction even in an environment that the spatial distribution of RF noise is changed abruptly, and the induced noise was about 16 dB lower than that in a dual coil antenna.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.405-410
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• 2017

The purpose of this study is to suggest the guideline by analysing and categorizing the case of sharing economy service especially the co-working and co-living space based on Europe. I did some literature research followed with evaluation of theoretical backgrounds, present conditions. Also, Some case research based on the keyword of 4th industrial revolution and the space categorized by their characteristics. The result indicate that co-working and co-living space's features correlated with their characteristics of the location and birth of digital nomad life. Each space has their flat-form community for the needs of closer cooperation between the user and user in common. I expect this study will become a good resource for upgrading domestic co-working and co-living space and also I hope that this study can guide follow-up next studies.

• Journal of the Institute of Convergence Signal Processing
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• v.20 no.2
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• pp.111-117
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• 2019

We investigated the variations in the magnetic-field distribution and power transmission efficiency, resulting from changes in the relative positions of the transmitting and receiving coils, for electromagnetic-induction-type wireless power transmission using an elliptical receive coil. Results of simulations using a high-frequency structure simulator were compared to actual measurement results. The simulations showed that the transmission efficiency could be maintained relatively stable even if the alignment between the transmitting and receiving coils was changed to some extent. When the centre of the receiving coil was perfectly aligned with the centre of the transmitting coil, the transmission efficiency was the maximum; however, the degree of decrease in the transmission efficiency was small even if the centre of the receiving coil moved by ± 10mm from the centre of the transmitting coil. Therefore, it is expected that the performance of the wireless power transmission system will not be degraded significantly even if perfect alignment is not maintained. The results suggested a standardized application method of wireless transmission in the utilization of wireless power for implantable sensors.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.12
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• pp.907-914
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• 2018

Wireless charging has been actively researched and popularized owing to the potential convenience of being able to charge electronic devices without wires for users. However, the receiver on the wireless charging pad is not charged when the center of the receiver is misaligned; thus, the center of the receiver must be adjusted well. This misalignment may greatly reduce the convenience of wireless charging. To overcome this limitation of wireless charging, a coil is designed to improve the positional freedom of the receiver. The positional freedom of the Rx coil is improved when the outer diameter of Tx coil is larger than when Rx and Tx coils are almost the same size. When the Tx coil has a larger outer diameter than that of the Rx coil, the efficiency at the center is somewhat lowered, but the efficiency is improved compared to when the center is out of order. In this paper, a double coil structure having an outer and an inner coil is proposed. The double coil structure further improves the efficiency, compared with one coil with the same outer size. The simulation and measurement results demonstrated that the tendency was consistent, and it was verified that the degree of freedom of the Rx coil is improved by adding the inner coil, while the size of the outer coil was the same. The measurement shows that the transmission efficiency of the conventional Tx coil is 37 %, the larger outer diameter coil is 45 %, and double coil is 47 % when the distance of the Tx/Rx coil is 3 mm, the misalignment is 15 mm and current flowing in the Rx coil is 1 A at an operating frequency of 105 to 210 kHz.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.83-92
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• 2015

Recently, Co-working that is a new trend of working and Co-working Space that create Co-working are increasing rapidly around the centers to support start-up such as one-person creative companies. However, the business centers located outside Seoul are not enough to recognize knowledge and skill for operating Co-working Space. Therefore, this study selects the big research issue which is "The recognition and case of co-working & application to co-working space" and the small research issue that is "Co-working Space operation activities" for qualitative research by using in-depth interview to managers of one-person creative company business centers. As a result, on the perspective of the big research issues, they understood Co-working concept, but the Co-working case was made by manager's effort without voluntary participation of the users. Co-working Space is important to recognize as a space for interaction and exchange information but was used only as a sharing space. And on the perspective of the small research issues, 'Space & Interior', 'Alliance and Partnership' and 'Community and Communication' show low awareness and activities. So, we suggest improvement plans through the case of best practices. This study is valuable, it could be a help to adapt and improve to Co-working Space in one-person creative company business center for creation of performance by Co-working.

• The Magazine for Energy Service Companies
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• s.59
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• pp.32-35
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• 2009

지난 1998년에 설립된 성림산업개발은 설립년수에 비해 에스코 사업실적과 노하우가 풍부한 기업이다. 열병합발전시설, 지역난방시설 및 자원회수시설 등 각종 플랜트설비의 설치공사와 유지관리 업무에 20여 년간 종사해온 기술인력을 주축으로 ESCO 시장의 중심에 우뚝 선 성림산업개발을 소개한다.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.766-767
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• 2008

임계온도가 높아 시스템응용에서 매우 안정한 장점을 지닌 고온초전도(HTS)도체를 이용한 HTS-SMES(Superconducting Magnetic Energy Storage)장치에 대하여 많은 연구가 진행되고 있다[1]-[2]. 이런 HTS-SMES 장치의 고가성, 복잡성 등 원인에 기인하여 운전에 앞서 장치의 임계전류, 자속유동손실 및 충.방전시 불가피하게 발생되는 교류손실 등과 같은 기본적인 특성들이 선행하여 연구되어야 한다. 따라서 본 연구에서는 600 kJ급 HTS-SMES코일에 대한 자장분석을 기반으로 코일의 임계전류밀도 분포를 계산하였고 최소 임계전류밀도에 근거하여 코일의 임계전류를 결정하였다. 그 주요 결과를 요약하면 코일에서 자장과 임계전류밀도 분포는 코일의 형상에 무관하게 같은 분포 경향을 보여주며 최소 임계전류밀도는 코일의 top과 bottom의 중심에 위치하며, model코일에서 임계전류의 계산값과 측정값이 비교적 잘 일치하였기 때문에 600 kJ급 HTS-SMES코일도 잘 일치할 것으로 사료된다. 또한 SMES코일을 20 K에서 운전한다고 가정하면 코일 임계전류의 ${\sim}60%$, 4.2 K에서는 ${\sim}40%$에서 각각 운전하게 될 것으로 예측된다.

• Proceedings of the Korea Contents Association Conference
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• 2013.05a
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• pp.83-84
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• 2013

이 연구는 코엔 형제 영화의 열린 결말이 작품의 주제와 어떻게 연관되는지, 그리고 그러한 열린 방식으로 내러티브를 종결시킬 수 있게 하는 서사 논리가 무엇인지 논의한다. <바톤 핑크>(1991), <노인을 위한 나라는 없다>(2007), <시리어스 맨>(2009) 등 코엔 형제의 열린 결말 영화들은 모두 '불확실성'에 관한 영화이다. 이 불확실성은 부조리하고 아이러니컬한 세상의 불가해성과 그것에 대한 캐릭터의 이해 불능으로 나타난다. 코엔 형제의 영화들은 바로 이러한 세계의 불가해성에 대한 논증의 내러티브이며, 이들의 열린 결말은 플롯과 논증의 중층 구조에서 스토리 문제의 해결이 아니라 논증의 완결을 추구한 결과이다.

• Journal of the Korean Magnetics Society
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• v.25 no.5
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• pp.162-168
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• 2015

The ${\mu}$-turn coil having a width of ${\mu}m$ on the GMR-SV (giant magnetoresistance-spin valve) device based on the antiferromagnetic IrMn layer was fabricated by using the optical lithography process. In the case of GMR-SV film and GMR-SV device, the magnetoresistance ratios and the magnetic sensitivities are 4.4%, 2.0%/Oe and 1.6 %, 0.1%/Oe, respectively. In the y-z plane the distribution of magnetic field of GMR-SV device and $10{\mu}$-turns coil which put under the several magnetic bead(MB)s with a diameter of $1{\mu}m$ attached to RBC (red blood cell) was analyzed by the computer simulation using the finite element method. When the AC currents of 20 kHz from 0.1 mA to 10.0 mA flow to the 10 turns ${\mu}$-coil, the magnetic field at the position of $z=0{\mu}m$ at the center of coil was calculated from $30.1{\mu}T$ to $3060{\mu}T$ in proportion to the current. The magnetic field at the position of $z=10{\mu}m$ was decreased to one-sixth of that of $z=0{\mu}m$. It was confirmed that the $10{\mu}$-turn coil having enough magnitude of magnetic field for the capture of RBC is possible to use as a biosensor for the detection of magnetic beads attached to RBC.