• 방사선산업학회지
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• 제2권1호
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• pp.35-42
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• 2008

The purpose of this study is to observe how the public impression of radiation is changing over the North Korea's nuclear bomb test. We found that the nuclear bomb test brought more negative impressions of radiation, but, in one year, more positive ones prevailed as in the pre-bomb-test. Those positive impressions were found to be composed of useful and positive elements mostly relative to health care. This suggests that we need to apply radiation (fusion) technology to solving everyday life problems in order to bring more positive impressions of radiation.

• Journal of Radiation Protection and Research
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• 제20권2호
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• pp.85-95
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• 1995

GM 계수관을 방사선 검출기로서 사용하고, 검출기의 신호를 디지탈 펄스로 변환하는 펄스처리회로와 디지탈 통신방식의 하나인 FSK(frequency shift keying) 변복조회로를 설계하였으며, 휴대용 무전기로 송수신되는 방사선 검출신호를 방사선량과 방사선량율로 개인용 컴퓨터의 화면에 표시하는 단일채널 무선 방사선측정 시스템을 개발하고 성능을 평가하였다. 성능검증 실험에서 펄스를 입력한 경우와 검출기에 방사선을 조사시킨 경우 펄스처리회로에서 약 5V의 동일한 디지탈 펄스가 출력되었고, 무선통신계통에서도 입력과 출력이 왜곡없이 송수신되고 있음을 확인하였다. 검출기에 표준방사선원(Cs-137)으로 방사선을 조사시켜 선량률을 측정한 결과 측정오차는 조사된 선량률의 10% 이내를 나타내었다. 본 시스템은 국내에선 처음으로 설계되었으며, 향후 다중채널로 구성하여 실시간 개인방사선피폭선량계, 방사선감시기 등 여러 용도의 방사선측정기에 응용함으로써 방사선방어에 기여할 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2151-2161
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• 2020

The study presents a review of research advancements in the field of gamma radiation detection systems for emergency radiation monitoring, particularly two major sub-systems namely (i) the radiation detector and (ii) the detection platform - air-borne and ground-based. The dynamics and functional characteristics of modern radiation detector active materials are summarized and discussed. The capabilities of both ground-based and aerial vehicle platforms employed in gamma radiation monitoring are deliberated in depth.

• Journal of Radiation Protection and Research
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• 제41권2호
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• pp.161-165
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• 2016

Background: Radiation accidents having occurred in recent containing the accident in Fukushima nuclear power plants of Japan were resulted to the increase in some public concern, anxiety and confusion for radiation or nuclear safety. The public anxiety for radiation is not being decreased though the announcements done in radiation research institutes in Korea. Therefore, this study aims at providing an effective system for radiation publicity to the public members by the clipping analysis for the radiation articles reported in the media. And, the relation between those radiation issues and the radiation perception to the public members is analyzed. Materials and Methods: The radiation articles reported by them in 2013 and 2014 have been collected, and they are then classified with the article characteristic, field and tendency. Classified articles have been reviewed by dividing as two year. The 210 articles have been compared for their tendencies, characteristics and fields by year reported, and their characteristic comparison by reported year are then reviewed. Results and Discussion: Though the frequency that the radiological accidents have occurred in worldwide is far low compared to the accidental frequencies occurred in the general industrial fields, the radiation perception is being still deteriorated because of its special problem, which is defined as exposure, contamination or radioactivity, about radiation. The basic principles for radiation communication were suggested for preventing some unnecessary misunderstanding due to the variation of understanding for radiation issues. Conclusion: It is necessary to perform a variety of strategies for the publicity in improving the radiation perception, to build a relationship with the press or the media and then to consistently interact with them. Radiation communication must be performed by radiation experts or complete charge department, and must be consistently performed and be taken predictable patterns.

• Journal of information and communication convergence engineering
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• 제10권2호
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• pp.97-102
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• 2012

The differential global positioning system (DGPS) transmits a GPS enhancement signal using a top-loaded monopole antenna in the medium frequency range. The top-loaded antenna in the medium frequency band can attain a radiation efficiency on the order of 10%. The antenna ground plane characteristics affect the antenna radiation efficiency. To improve the radiation efficiency, it is necessary to install the antenna on a ground plane with large enough physical dimensions and good conductivity. The antenna radiation efficiency is a primary factor in determining the DGPS service area. The service area of the DGPS using a medium frequency band is dominantly affected by the antenna radiation efficiency. To determine antenna radiation efficiencies accurately, the antenna radiation efficiencies of DGPS are deduced from the propagation power in this paper. Based on the deduced antenna radiation efficiencies, the service area for the Korean nationwide-DGPS is analyzed and evaluated.

• 전기학회논문지
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• 제62권7호
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• pp.963-968
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• 2013

Ionizing Radiation effects on MOS devices provide useful information regarding the behavior of MOS based devices and circuits in the electronic instrumentation parts and instructive data for making the high sensitive sensors. The study presents the results of the analysis on the structural characteristics of MOS capacitor for sensing the ionizing radiation effect. We performed numerical modeling of Ionizing-radiation effect on MOS capacitor and simulation using Matlab program. Also we produced MOS capacitors and obtained useful data through radiation experiment to analyse the characteristic of ionizing radiation effect on MOS capacitor. Increasing the thickness of MOS capacitor's oxide layer enhanced the sensitivity of MOS capacitor under irradiation condition, but the sensitivity of irradiated MOS capacitor is uninfluenced by the area of MOS capacitor. The high frequency capacitance of the MOS capacitor is found to be strongly affected by incident ionizing radiation.

• 전기전자학회논문지
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• 제18권4호
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• pp.552-558
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• 2014

본 논문에서는 원격 방사선 측정을 위한 ZigBee 원칩형 통신 모듈 설계방법을 제안한다. 제안된 ZigBee 원칩형 통신모듈 설계는 ZigBee 시스템 구성을 위해 일반적으로 사용되는 2개의 칩 제어 프로세서와 ZigBee RF 디바이스로 구성되는 방식을 한 개의 칩 모듈로 설계한다. 원격 방사선 측정을 위한 ZigBee 원칩형 통신 모듈은 무선통신 통합제어부, 센서 및 고전압 발생부, 충전 및 전원회로부, 유선통신부, RF 회로부 및 안테나부 등으로 구성된다. 무선통신 통합제어부는 ZigBee를 위한 무선통신 제어 기능 및 방사선 측정 및 제어를 위한 기능을 수행한다. 센서 및 고전압 발생부는 2차에 걸쳐 500V의 고전압을 생성하여 GM Tube를 통해 감지된 방사선에 대한 펄스를 증폭 필터링 하는 기능을 수행한다. 충전 및 전원회로부는 리튬이온 배터리의 충전 및 원칩 프로세서에 전원을 공급하는 기능을 수행한다. 유선통신부는 PC와의 인터페이스 및 디버깅을 위한 USB 인터페이스 및 원거리 유선 통신이 가능하도록 RS-485/422 인터페이스 기능을 수행한다. RF 회로부 및 안테나부는 칩안테나를 적용할 수 있도록 RLC 수동소자를 적용하여 BALUN 및 안테나 임피던스 매칭 회로를 구성하여 무선통신이 가능하도록 한다. 제안된 원격 방사선 측정을 위한 ZigBee 원칩형 통신 모듈을 설계 실험한 결과, 10m, 100m 구간에서 모두 데이터가 정상적으로 전송되어서 원격 방사선량 측정이 되었음을 확인할 수가 있었다. 또한 낮은 소비전류와 적은 비용으로 원격 방사선량 측정환경을 구축할 수 있었다. 따라서 방사선 측정장치의 선형성 확보 및 장치의 소형화를 통해 안정적인 방사선 측정 및 실시간 모니터링 환경을 구축할 수가 있었다.

• Current Optics and Photonics
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• 제1권5호
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• pp.440-455
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• 2017

In this paper, we carry out a performance analysis of a two-user free-space optical (FSO) communication system with photodetector multiplexing, in which the two users are defined as the primary user (PU) and secondary user (SU). Unlike common single-user FSO systems, our photodetector multiplexing FSO system deploys a shared detector at the receiver and enables PU and SU to send their own data synchronously. We conduct the performance analysis of this FSO system for two cases: (1) in the absence of background radiation, and (2) in the presence of background radiation. Decision strategies for PU and SU are presented according to the two scenarios above. Exact and approximate conditional symbol-error probability (SEP) expressions for both PU and SU are derived, in an ideal channel with no fading. Average SEP expressions are also presented in the no-background-radiation scenario. Additionally, in some particular cases where the power ratio tends to 0.5 or 1, approximate SEP expressions are also obtained. Finally, numerical simulations are presented under different conditions, to support the performance analysis.

• 한국산학기술학회논문지
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• 제21권9호
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• pp.397-404
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• 2020

현재 운영되고 있는 군 지휘·지원차량은 상용차량의 일부를 개조하여 제작되었으며, 군에서 필요한 통신장비 운용환경을 확보하기 위하여 통신실 내부에 별도의 컨버터를 장착하는 전원공급시스템이 적용되었다. 하지만, 이러한 전원공급시스템은 전자파 방사 노이즈를 발생시켜 차량에서 무전교신 시 잦은 잡음과 통신감도 저하 등의 문제점이 발생되었다. 이를 개선하기 위해, 엔진에 발전기를 추가 장착하여 통신장비에 필요한 전력을 공급받도록 전원공급시스템을 변경하였다. 추가 장착된 발전기는 통신장비가 운용되는 통신실과 완전히 분리된 엔진 룸에 위치하도록 설계되어 전원공급시스템에서 발생되는 전자파 방사 노이즈에 의한 영향을 감소시켜줄 것으로 기대되었다. 개선된 시스템의 효과를 검증하기 위하여 기존 차량과 신규 전원공급시스템이 적용된 차량에 대하여 광대역 방사시험을 각각 수행하였고 측정 결과를 비교하였다. 시험 결과 신규 전원공급시스템이 적용된 차량의 광대역 방사 노이즈는 국내 자동차 안전기준에 모두 만족하였으며, 기존 차량 대비 일부 주파수 구간을 제외한 대부분의 구간에서 감소함을 확인할 수 있었다. 특히, 차량 우측면의 수직편파 170~225 MHz 구간에서 최대 10.751 dB𝜇V/m 감소하였다.

• Journal of information and communication convergence engineering
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• 제10권3호
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• pp.225-230
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• 2012

The Korean nationwide differential global positioning system (NDGPS) reference station transmits a global positioning system (GPS) enhancement signal using minimum shift keying modulation with a 200 bps data rate. The ocean-based DGPS covers the service area of 100 NM with 300 W output power; on the other hand, the land-based DGPS transmits the output power of 500 W, which covers the service area of 100 km. The DGPS reference stations with high output power can radiate spurious signals, which may act as interference sources affecting the other DGPS reference stations or the wireless ground stations that utilize the medium frequency band. In this paper, the radiation spectrums of the DGPS reference stations are measured and analyzed in the spurious domain. The DGPS radiation spectrums are evaluated from the perspective of the interference effect.