• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.175.1-175.1
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• 2008

• Journal of electromagnetic engineering and science
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• v.3 no.1
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• pp.12-16
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• 2003

In this paper, low noise amplifiers with coplanar waveguide structure are presented for Wireless LAN data communication application. For comparison of microwave performance, LNAs of cascode type and balanced type using cascode cell with the same substrate and same bias conditions are designed and implemented. A cascode type of LNA shows the gain of 12.45 ㏈, input return loss of 11.63 ㏈, and noise figure of 1.52㏈. A balanced type of LNA using cascode cell shows the gain of 6.58 ㏈, input return loss of 16.6 ㏈, and noise figure of 1.18 ㏈.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.697-706
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• 2000

In this paper, new bandpass filters that are composed of microstrip ring resonators with the center frequency of 5.775 GHz and the bandwidth of 100 MHz are presented. For the suppression of the unnecessary harmonics, lowpass filters are inserted into the feedlines and ring resonator itself, respectively These bandpass filters show good microwave characteristics with the harmonic suppression ratio of about 39 dB and 35 dB, respectively. Also, the varactor-tuned microstip ring bandpass filter with harmonic suppression is suggested and the tuning bandwidth of more than 450 MHz is obtained.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.6
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• pp.969-975
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• 2000

New class of three dimensional (3-D) micromachined microwave planar filters at K and Ka-band are presented using LIGA micro-machined process. The K-and Ka-band filters show wide bandpass characteristics of~36% and ~39% with the insertion loss 1.26dB at 19.11GHz and 1.7dB at GHz, respectively. These filters can be applicable in high power MMIC of MIMIC.

• The Journal of Korean Academic Society of Nursing Education
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• v.19 no.2
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• pp.137-150
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• 2013

Purpose: The purpose of this study was to identify the degree of safety education requirement in child daycare center teachers. Method: The data using questionnaire were collected from eight child daycare centers located in Seoul, Gyounggi-Do, and Kwangwon-Do. Final participants were 133 child daycare center teachers. Results: The degree of safety education requirement were as follows: education need of safety knowledge ($4.26{\pm}.50$), safety education need of daycare center ($3.29{\pm}.60$), recognition about safety education training ($3.94{\pm}.58$), and confidence of safety care practice ($2.75{\pm}.43$). There is significant correlation between education need of safety knowledge and safety education need of daycare center (r=.495, p<.001), education need of safety knowledge and recognition about safety education training (r=.555, p<.001), education need of safety knowledge and confidence of safety care practice (r=.201, p=.020), safety education need of daycare center and recognition about safety education training (r=.464, p<.001), and recognition about safety education training and confidence of safety care practice (r=.187, p=.032). Conclusion: On this study, child daycare center teachers' safety education requirement was relatively high. It is recommended that safety education for them should be done for children's healthy life.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.321.2-322
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• 2001

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.100.2-100.2
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• 2007

• Journal of Korean Elementary Science Education
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• v.31 no.2
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• pp.177-187
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• 2012

The purpose of this study was to acquire a better of how creativity center is perceived among students, teachers and parents by administering a questionnaire. A total of 320 people participated in this survey. We developed the questionnaire which as categorized by four specific areas: 1) people's overall perceptions of creativity education; 2) the way of using the creativity center 3) programing of creativity center 4) space composition of the creativity center. The summary of survey results included; firstly, people had paid attention to creativity education and creativity education; secondly, they want to make use of creativity center with informal learning and extra-curriculum; thirdly, they prefer to participate in many experience activities such as camp or experiments; lastly, they more need creativity experience program and utilization of DIY education. In conclusion, students, teachers and parents recognized creativity center is needed. Therefore, more intensive research and follow-up study on building creativity center should be highly considered.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.25-28
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• 2002

In this paper, a micromachined millimeter-wave end-gap band-pass filter (BPF) is presented. The millimeter-wave BPF is designed using 3D design software, Zeland IE3D with the center frequency of 60 GHz, band width of 3 GHz, ripple of 1㏈ and insertion loss of 2.5dB. This type of micromachined BPF can be used in millimeter-wave circuit.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2006.07a
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• pp.720-720
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• 2006