• 제목/요약/키워드: C-line

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Developing a Curriculum of Management for Engineers - A Case of the C University (공학도를 위한 경영학 교과목 개발 연구 - C대학교 강좌 개발 사례)

  • Limb, Seong-Joon;Choo, Seung-Youp
    • The Journal of Korean Institute for Practical Engineering Education
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    • v.3 no.1
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    • pp.84-91
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    • 2011
  • It is necessary for the engineering students to have a business mind for the contemporary world of business. We developed a focused management education program for engineering students in C-University. The management education program consists of both on-line and off-line learning. ABEEK requires 720 engineering students of C-University must take basic management course. The on-line lecture was developed to overcome the shortage of qualified lecturers in business school. On-line lecture made by the business school faculty(not lecturers) can evenly provide high-quality content for every engineering students. In addition, the program is designed that off-line classes administered by lecturers complements the limitations of on-line lecture. Having in mind that selected senior engineering students understand technology and basic business, we developed an advanced course focusing on technology-oriented venture businesses. On and off-line blended learning and two-step approach of management education for engineering students of C-University may shed some light on other engineering schools in similar situation.

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Cytotoxic Activities of Red Algae Collected from Jeju Island Against Four Tumor Cell Lines

  • Kim, Kil-Nam;Lee, Ki-Wan;Song, Choon-Bok;Ahn, Chang-Bum;Jeon, You-Jin
    • Preventive Nutrition and Food Science
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    • v.11 no.3
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    • pp.177-183
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    • 2006
  • Methanolic and aqueous extracts of 26 red algae species collected from Jeju Island coast were prepared at a high $(70^{\circ}C)$ and a room temperature $(20^{\circ}C)$ and were examined for their cytotoxic activity against 4 tumor cell lines: U-937 (human monoblastoid leukemia cell line), HL-60 (human promyelocytic leukemia cell line), B-16 (murine melanoma cell line) and HeLa (woman cervical carcinoma cell line). $20^{\circ}C$ methanolic extract of Polysiphonia japonica showed cytotoxic activity of over 50% against U-937, HL-60 and B-16 cells. On the other hand, the $20^{\circ}C$ aqueous extract of Scinaia okamurae and $70^{\circ}C$ aqueous extract of Chondrus crispus showed cell growth inhibition activity of more than 50% against HL-60 and B-16 cells. The highest cytotoxic activity was observed in the $20^{\circ}C$ aqueous extract of Scinaia okamurae against B-16 cells (80.55%).

The Design and Characteristics of the Line Coupler for Power Line Modem (전력선 모델을 위한 Line-Coupler의 설계 및 특성)

  • Park, Chong-Yeun;Cho, Gye-Hyun
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3132-3134
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    • 1999
  • To realize the power line communication system, the line coupler is one of the most important systems, which must be adjustable to the power line characteristics. In this paper, three kinds of line couplers were designed and simulated with the Pspice, which could be useful to the power line communication systems in C-Band(95kHz-148.5kHz) frequency

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A new line to line fault location algorithm in distribution power networks using 3 phase direct analysis (3상회로의 직접해석에 의한 배전계통 선간단락 사고 고장거리 계산 알고리즘)

  • Jin, B.G.;Choi, M.S.;Lee, S.J.;Yoon, N.S.;Jung, B.T.;Lee, D.S.
    • Proceedings of the KIEE Conference
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    • 2002.07a
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    • pp.108-110
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    • 2002
  • In this paper, a fault location algorithm is suggested for line to line faults in distribution networks. Conventional fault location algorithms use the symmetrical component transformation, a very useful tool for transmission network analysis. However, its application is restricted to balanced network only. Distribution networks are, in general, operated in unbalanced manners, therefore, conventional methods cannot be applied directly, which is the reason why there are few research results on fault location in distribution networks. Especially, the line to line fault is considered as a more difficult subject. The proposed algorithm uses direct 3-phase circuit analysis, which means it can be applied not only to balanced networks but also to unbalanced networks like distribution a network. The comparisons of simulation results between one of conventional methods and the suggested method are presented to show its effectiveness and accuracy.

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A Study on the Characteristic of Variable Impedance Line using DGS (DGS를 이용한 가변 임피던스 선로 특성에 관한 연구)

  • Kim Young-Ju;Joung Myoung-Sub;Park Jun-Seok;Cho Hong-Goo
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.54 no.1
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    • pp.35-40
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    • 2005
  • In this paper, we designed and fabricated the variable impedance line by using the DGS(Defected Ground Structure) which is useful in mounting the external lumped elements. Also we used a varactor diode as Control device stuff at the proposed variable impedance line. We are able to change the impedance of transmission line as varied the capacitance of varactor diode by adjusting DC bias. The impedance variation of the proposed DGS line is about maximum 70 Ω. We will study about the application of DAM(Direct antenna modulation) in the future work.

Global Far-UV Emission-line Images of the Vela Supernova Remnant

  • Kim, Il-Joong;Seon, Kwang-Il;Min, Kyoung-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.110.2-110.2
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    • 2011
  • Nishikida et al. (2006) presented the first far-ultraviolet (FUV) em${\lambda}$ission-line images of the Vela supernova remnant (SNR) obtained with FIMS/SPEAR instrument. Those include C III ${\lambda}$977, O VI ${\lambda}{\lambda}$1032, 1038, Si IV+O IV] ${\lambda}{\lambda}$1393, 1403 (un-resolved), C IV ${\lambda}{\lambda}$1548, 1551 emission-line images. As a following work, we re-constructed these emission-line images using the new-version processed FIMS/SPEAR data. Additionally, we made N IV] ${\lambda}$1486, He II ${\lambda}$1640.5, O III] ${\lambda}{\lambda}$1661, 1666 emission-line images. The new-version images cover the whole region of the Vela SNR and show more resolved features than the old-version. We compare these FUV emission-line images with other wavelength (X-ray, optical, etc.) images obtained in previous studies.

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RF Channel Characteristics of the Medium-voltage Power Line for PLC (전력선통신을 위한 중 전압용 전력선의 RF채널 특성)

  • Kim, Seon-Hyo;Kim, Gwan-Ho;Lee, Hyeong-Cheol;Sin, Cheol-Jae
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.51 no.7
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    • pp.316-321
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    • 2002
  • In this Paper, the channel characteristics of the medium voltage(22.9kV) power line to analysis the broadband power line communication in the frequency range up to 30MHz was measured. With the sideband electrical coupler in the operating frequency range from DC to 30MHz, we measured characteristic impedance, noise and attenuation of the medium voltage power line, and then characteristic impedance was measured at the state of unloaded medium voltage power line by Scattering parameter method of Vector Network Analyzer. As a measurement result, Channel impedance shows 100~380$\Omega$ at the less than 15MHz and 70~230$\Omega$ at the more than 15 MHz. Noise characteristics of power line shows -75dBm at 20MHz and Narrowband interference noise was from 3 MHz to 7MHz.

Effects of Cancer Prevention and Immune Stimulation of Fractions from Capsosiphon fulvescens (매생이 추출분획의 암 예방 및 면역증진 효과)

  • Kim, Nam-Young;Jang, Min-Kyung;Lee, Dong-Geun;Lee, Jae-Hwa;Ha, Jong-Myung;Ha, Bae-Jin;Jang, Jeong-Su;Lee, Sang-Hyeon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.5
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    • pp.1249-1253
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    • 2006
  • The fractions of Capsosiphon fulvescens were studied to verify the anticancer and immunostimulating activity. The fractions from the ethanol extract of C. fulvescens were prepared by the systematic extraction procedure with the solvents such as hexane, ethyl ether, methanol, butanol and H$_2$O. The cytotoxic effects of C. fulvescens fractions against human leukemia cell line U937, mouse neuroblastoma cell line (NB41A3), human hepatoma cell line (HepG2)and rat glioma cell line (C6) were investigated. Ethyl ether fraction of C. fulvescens showed the highest cytotoxicity against all four cell lines tested. In addition, H$_2$O fraction also showed relatively high cytotoxicity. Dose dependent patterns were observed on all four cell lines. The immune-stimulating effects of C. fulvescens fractions on rat macrophage cell line (RAW 264.7) were also investigated. All five fractions of C. fulvescens extract stimulated NO production with concentration dependant manner. These results suggest that C. fulvescens may be a useful candidate for a natural antitumor and immune-stimulating agent.

Cervical Transforaminal Axis Measured by MRI and Its Relation to the Internal Jugular Vein, Internal Carotid Artery and Vertebral Artery (자기공명영상장치를 이용해 측정한 경부 경추간공의 축과 내경정맥, 내경동맥, 척추동맥과의 관계 연구)

  • Kang, Sang Soo;Choi, Eun Seon;Park, Jun Hee;Hong, Seong Jun;Kim, Il Seok;Yun, Yeong Jun;Shin, Keun Man
    • The Korean Journal of Pain
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    • v.20 no.2
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    • pp.143-147
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    • 2007
  • Background: The safety of cervical transforaminal epidural block has been the subject of debate, therefore, this study was conducted to measure the angle of the cervical transforaminal axis and to investigate its relationship to the internal jugular vein, internal carotid artery and vertebral artery. Methods: One hundred cases of cervical MRI were reviewed. The angle between a line passing through the center of the vertebral body and spinous process and a line passing through the center of the lamina in C3-4, C4-5 and C5-6 was measured and designated as A-degree. Additionally, we drew a line at the back of the vertebral artery that ran parallel to a line passing through the center of the lamina, which was presented as A-line. We then examined the distribution of the area in which the internal jugular vein and the internal carotid artery were located. Results: The mean values of the A-degree in C3-4, C4-5 and C5-6 were $53.5{\pm}4.3$, $54.2{\pm}4.6$ and $54.3{\pm}4.8$, respectively. There were no statistically significant differences among age groups or vertebral levels (ANOVA test, P > 0.05). The A-line was distributed primarily throughout zone 3, 4, and 5 in C3-4 and zone 5 in C4-5 and C5-6. Conclusions: The results of this study indicate that the mean values of A-degree were not statistically different among each age group and each vertebral level. However, the A-line may be located in the zone in which the internal jugular vein and the internal carotid artery lie and individual differences in the A-degree remain.

An Application of the On Line Partial Discharge Measurement Method in Transformer (온라인 변압기 부분방전 측정기법 적용)

  • Kweon, Dong-Jin
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.8
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    • pp.394-400
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    • 2001
  • This paper describes an application of the on line partial discharge measurement method in operating transformer. In the operating transformer, the partial discharge signal may be superimposed by radio intereference voltage(RIV) and pulse shaped noise signals generated by external corona. The partial discharge quantity showed about 3,800pC due to very high sinusoidal interferences at the measuring impedance terminal of the transformer bushing tap. In order to reject these noises, this paper applied RIV filter, band-pass filters and noise gating method. The resulting measuring sensitivity was improved from 3,800pC to 160pC.

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