• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.1631-1632
• /
• 2015

기술의 발전과 사회/환경변화, WTO/TBT 및 FTA 협정 이행을 위한 국제표준 도입 등 대내 외적 환경에 능동적/선제적으로 대처하기 위하여 국제표준 수준의 규정인 한국전기규정(KEC) 제정(안)을 개발하고 있다. 한국전기규정(KEC)은 국제표준인 IEC를 근간으로 하고, 상세사항은 DIN, BS, NEC 등의 선진표준을 참조, 국내외 표준들의 비교/조사를 통한 개발을 목적으로 제정 중에 있다. 한국전기규정(KEC)은 제1편 공통분야와 제2편 저압전기설비분야, 제3편 고압전기설비분야, 제4편 지능형전력망분야 등 총 4편으로 구성되며 이 중 피뢰시스템은 IEC 62305를 기초로 하여 제정되었다. 본 논문에서 한국전기규정(KEC) 제1편 제5부 피뢰시스템분야에 대한 중요사항에 대해 제시하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.411-415
• /
• 2003

In this paper, a reflector type frequency doubler for local oscillator at 24GHz is designed and fabricated with ne71300-N MESFET. Optimum source and load impedances are decided through a multiharmonic load pull simulation technique. A conversion gain ran be improved using the reflector and fundamental and third harmonics are well suppressed with open stub of λ/4 length. Measured results show output power at 0dBm of input power is -3.776dBm, conversion gain 0.736dB, harmonic suppression 41.064dBc, respectively.

• Journal of Navigation and Port Research
• /
• v.28 no.1
• /
• pp.37-41
• /
• 2004

In this paper, a reflector type frequency doubler for local oscillator at 24GHz is designed and fabricated with ne71300-N MESFET. Optimum source and load impedances are decided through a multiharmonic load pull simulation technique. A conversion gain can be improved using the reflector and fundamental and third harmonics are well suppressed with open stub of $\lambda$/4 length Measured results show output power at 0dBm of input power is -3.776dBm, conversion gain 0.736dB, harmonic suppression 41.064dBc, respectively.

• Food Science and Biotechnology
• /
• v.16 no.6
• /
• pp.894-901
• /
• 2007

This study investigated the effects of cell cultured Acanthopanax senticosus extract (ASE) supplementation and swimming exercise on lipid profiles and carnitine concentrations in C57BL/6J mice fed high fat diets. Male C57BL/6J mice (n=50), aged 4 weeks, were divided into 5 groups based on exercise and/or ASE supplementation (0.5 g/kg of body weight): normal diet (N-C), high fat diet (H-C), high fat diet non-supplement & exercise (H-NSE), high fat diet supplement & no exercise (H-SNE), high fat diet supplement & exercis (H-SE). Liver nonesterified carnitine (NEC) was significantly higher in the H-SNE group than in the H-C group, and liver total carnitine (TCNE) levels were significantly higher in the H-SNE group than in the H-NSE and H-SE groups. Liver and muscle carnitine palmitoyltransferase-I (CPT-I) mRNA levels tended to be higher with ASE supplementation and/or exercise. These results suggest that supplementation with ASE and/or exercise might have a role in improving lipid oxidation.

• Proceedings of the KIEE Conference
• /
• 2002.07d
• /
• pp.2280-2284
• /
• 2002

This study is to develop a time measure system for acceleration of gravity verification. The system can measure time interval between two points when an object passes through the points. The system has 1${\mu}$sec time resolution. The AT90S8515 microprocessor, product of ATMEL. can make 1${\mu}$sec time resolution possible connected with the 8 MHz fine crystal oscillator. The two external signals called 'start' and 'stop' have AT90S8515 that counted time intervals of the two signals. Sensors are composed of the IR beam emitting diode. TNL108 and the IR beam receiving photo diode, TNL601, produced by NEC company. In order to acquire the measurement of exactitude of the system, measure the pendulum period. Experimental result, the average period =3.0406sec with pendulum length of 2.314m. The acceleration of gravity g=$908821{\pm}6.416{\times}1^{-4}m/s^2$.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.28A no.9
• /
• pp.721-728
• /
• 1991

In this paper, a magneto-optic modulator has been designed by using single crystal BSO and polycrystal ZnSe as Faraday cells. And practical core-type optical current sensors using pure iron and permalloy have been prepared and experimented. In order to obtain efficient magnetic field detection, LED(NEC OD08358, 0.87 $\mu$m) was used as optical source, PIN-PD(OD-8454)as optical receiver and multi-mode optical fiber (100/140$\mu$m) as transmission line. The characteristics matrix of the optical element was calculated by Stokes parameter, and optic modulation characteristics equations were derived by Muller matrix. Electromagnetic analysis program (FLUX 2D, micro VAX 3600) by finite element method was used to find the magnetic flux density around the core. The measuring error of the output voltage to input current has been masured below 5% in the range of 50A to 1000A. As the temperature was changed from -20$^{\circ}C$ to 60$^{\circ}C$, the maximum measurement error of the optical output has been found to be 0.5% at 60$^{\circ}C$. These experimental results show good temperature and linearity characteristics. The SNR of the overall system was 47dB in case of 600A (250.2 Oe) conductor current and the system has good noise immunity.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.25 no.2
• /
• pp.375-387
• /
• 1995

The purpose of this study was to quantitatively evaluated experimental tooth root resorption for digital radiography. For this study, experimentally three root sites were used, and radiograms were taken with standardized apparatus. Digital imaging system were consisted of NEC PC-980l(computer), TRINITRON(monitor), SONY XC-711 CCD camera. The display monitor had a resolution of 512X512 pixels. The obtained results were as follows: 1. In the difference of the four X-ray film of the contrast correction, the contrast difference was one gray scale variation at mean value. 2. Viewing of the view box of the periapical radiographs, experimental tooth root resorption of the periapical area of the first premolar, middle of mesial surface of the first molar mesial root, middle of lingual surface of the first molar distal root were recognized by increased diameter. 3. On the analysis by histogram, the periapical area of the first premolar, the middle of mesial surface of the first molar mesial root were each recognized tooth root resorption of the 5,6,7 pixel, 2,4,5 pixel by increased diameter. 4. On the analysis by histogram, the middle of lingual surface of the first molar distal root was each recognized tooth root resorption of the none, 3,6 pixel by increased diameter.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.7
• /
• pp.1558-1564
• /
• 2004

This paper shows the design of Active antenna which appled to 5.5GHz RF module for local wireless communication system. The LNA, which was designed Super low noise HJ FET of NE3210S01, is used to obtain a good noise figure characteristics. And the microstrip patch antenna was designed to obtain omnidirectional antenna characteristics. The measured LNA gain is 15 dB, input & output return loss is under -20 dB and VSWR under 1.5. The Single microstrip patch antenna input return loss is under -29 45, VSWR under 1.2.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2002.11b
• /
• pp.1273-1276
• /
• 2002

슈퍼컴퓨팅센터는 현재 Cray T3E, NEC SX-5, Compaq SMP, IBM p690 등의 시스템을 보유하고 있으며, 1년 평균 600구좌 이상의 슈퍼컴퓨팅 서비스를 제공하고 있다. 이에 따라 사용자의 기본 시스템 사용법, 프로그램 컴파일, 디버깅 및 상용 프로그램 사용 관련 질의가 하루 평균 수십 건씩 이루어지고 있다. 이러한 사용자 상담 창구의 일원화 및 효율화를 위해 이미 HelpDesk를 운영하여 사용자 질의를 진화, 웹 게시판, 메일 등을 통하여 접수받아 처리하고 있다. 하지만, 이와 같은 방식은 같은 질의가 빈번할 경우 담당자가 동일한 질의 해결에 많은 시간을 소비하게 한다. 이러한 슈퍼컴퓨터 사용 시 발생하는 문제를 체계적으로 상담하기 위해 각 사용자 질의를 티켓(Ticket)이라는 한 개의 이벤트로 표시하고, 이러한 티켓에 의거 문제를 해결하기 위해 여러 관련 담당자 상호간에 협력할 수 있도록 사이버 HelpDesk 시스템을 구현함으로써 사용자에게 신뢰성 있는 서비스를 제공할 수 있게 하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.1A
• /
• pp.41-46
• /
• 2003

A MF/HF marine whip antenna with side whips, which are connected at an angle with the straight main whip, has reported In this paper, the effects of side whips on the antenna are simulated by using NEC-WIN and a novel MF/HF ship antenna with side whips is designed First of all, the gain, return loss, and radiation pattern of the antenna on infinite perfect conductor plane are simulated as function of the parameters of the side whip, such as the number, the location, the length of the side whip and the angle with the main whip. After that, the size of the antenna is decided and set up on an experimental ship in Korea Maritime University. The antenna on the ship are simulated and the simulated input impedances are good agreement with the measured results.