• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.50-51
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• 2000

가속된 전자빔을 금속회절격자의 위로 통과시킬 때 결맞은 복사광(coherent radiation)이 발생하는데 이를 Smith- Purcell 효과라고 한다. 이때 발생하는 전자기파의 파장은 회절격자의 주기, 전자빔의 속도 및 복사광의 방출각도에 관계된다$^{(1)}$ . 그리고 방출된 복사광의 출력세기는 전자빔의 군집을 고려하지 않는 경우, 회절이론(diffraction theory)에 의해 얻을 수 있는데, 그 세기는 입사시킨 전자빔의 전류세기에 선형적으로 비례한다$^{(2)}$ . (중략)

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.135.1-135.1
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• 2012

위성 및 발사체 등 지상 및 우주에서 운용되는 시스템은 발사 및 궤도 내 운용환경에서의 다양한 전자파환경에 노출되며 이를 모사하는 전자파환경시험을 전자파챔버에서 수행하게 된다. 전자파챔버에서의 전자파환경시험은 크게 방출시험과 내성시험으로 구분된다. 그 중 복사성 내성시험은 안테나를 통해 방출되는 전기장 에너지를 시험 대상 유니트 또는 시스템에 복사함으로서 발생되는 시험품의 정상동작 여부를 판단하는 시험이다. 이 때, 안테나로부터 복사되는 전기장의 세기는 주파수 및 안테나 타입에 따라 상이한 형상을 가지므로 시험품에 복사되는 전기장 에너지 또한 그에 따른 형상을 가지게 된다. 이에 따라 전자파챔버에서 복사성 내성 시험을 수행할 때 주파수 및 안테나 타입에 따른 필드 균일성 패턴을 측정하고 안테나 빔 중심과 그 주변에서 발생되는 전기장 세기를 정량적으로 평가함으로써 시험품에 대한 복사성 내성시험을 수행함에 있어 시험품 영역에 따른 내성특성을 확인할 수 있을 것이다. 본 논문에서는 한국항공우주연구원 전자파챔버에서 사용하는 복사성 내성 시험용 안테나에 대해 시스템 및 유니트 시험영역에서 필드 균일성 시험을 수행함으로서 위성 또는 발사체 시스템 및 유닛에 복사되는 전기장의 분포 특성을 분석하였다.

• The Optical Journal
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• v.3 no.11 s.11
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• pp.68-77
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• 1991

• Journal of the Korea Society of Computer and Information
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• v.20 no.4
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• pp.57-67
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• 2015

The concept of detection and classification of objects based on infrared camera is widely applied to military applications. While the object detection technology using infrared images has long been researched and the latest one can detect the object in sub-pixel, the object classification technology still needs more research. In this paper, we present object classification method based on measured radiant intensity of objects such as target, artillery, and missile using infrared camera. The suggested classification method was verified by radiant intensity measuring experiment using black body. Also, possible measuring errors were compensated by modelling-based correction for accurate radiant intensity measure. After measuring radiation of object, the model of radiant intensity is standardized based on theoretical background. Based on this research, the standardized model can be applied to the object classification by comparing with the actual measured radiant intensity of target, artillery, and missile.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.7
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• pp.1121-1127
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• 2000

Among many EMI suppression techniques for radiated emissions from PCB traces, image technique is adapted in this paper. A model for the analysis of the effect of image plane on the radiation of a microstrip trace is presented. After a simulation was carried out by using the FEM(Finite Element Method), field strength was measured with electric probe. The radiated emission levels were measured for various image plane width, separation distances, and their results show that the measured data are very close to those of simulation result. It proves that a proper use of image planes on the PCBs is very effective means of reducing EMI emissions on the PCBs.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.1
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• pp.9-14
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• 2005

The angular dependence(profile) of backward radiated ultrasound was measured for glass specimens with random surface roughness using ultrasonic goniometer that ran changes the incident angle continuously. It was concluded that the roughened region had greater acoustic impedance than the unperturbed region. The comparison of backward radiations showed that the amplitude of peak and the area of radiation profile were increased with surface roughness. It was suggested from the sensitive dependence of the profile area that the profile of backward radiation could be applied to in the nondestructive evaluation of sulfate region. Inclined C-scan technique with the transducer inclined at Rayleigh angle showed the reverse of luminosity and the high signal to noise ratio so that it provided high resolution.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.2
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• pp.234-241
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• 2000

During the EFT immunity test, the fast transient voltage is injected to the power or signal line. The radiated noise from these lines influences the near-by EUT, and consequently, the reliability of the test result can be jeopardized. The measured data of the field strength and wave shape of the noise were compared with the result of the mathematical analysis using transmission line model. When the tests were performed by the conditions the same as stated in IEC 61000-4-4, the results showed that the magnitude of the radiated electric field strength was about 2.4KV/m, and it can cause severe interference to the intended operation of EUT.

• The Korean Publising Journal, Monthly
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• s.334
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• pp.22-23
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• 2003

• The Optical Journal
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• s.128
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• pp.28-30
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• 2010

1960년 국내 시장에 처음으로 복사기를 선보여 사무기기 업체라는 새로운 분야를 개척한 신도리코(대표 우석형, www.sindoh.com)가 올해 7월 7일 창립 50주년을 맞이한다. 지난 반세기 동안 사무용 복합기 시장에서 한 번도 빠짐없이 점유율 1위를 고수해온 저력을 바탕으로 글로벌 브랜드 'SINDOH'와 함께 세계 속에 새로운 50 년의 역사를 세우기 위해 힘찬 도약을 준비 중인 신도리코의 최종하 전무를 만나 신도리코의 그간 행보와 새로운 반세기 도전을 향한 비전을 들어보았다.

• Korean Journal of Optics and Photonics
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• v.21 no.4
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• pp.133-138
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• 2010

All radiation thermometers have a size-of-source effect (SSE) and a self-radiation effect (SRE). The SSE,defined as dependence of the detector signal of a radiation thermometer on the diameter of a source, is critically dependent on the wavelength since diffraction is the main cause. In this paper, we have measured the SSE and the SRE of TRT2 (Transfer Radiation Thermometer 2, HEITRONICS) widely used as a transfer standard in low and middle temperature range. At $300^{\circ}C$, The radiation temperature difference between the 60 mm diameter blackbody and 10 mm diameter blackbody due to the SSE was estimated to be $3.5^{\circ}C$ in low temperature mode ($8-14\;{\mu}m$) and $0.5^{\circ}C$ in middle temperature mode ($3.9\;{\mu}m$). In addition, the measured radiation temperature difference of the blackbody due to the SRE was found to be 110 mK when the body temperature change of TRT2 was set at $2.6^{\circ}C$.