• 한국해양학회지
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• v.4 no.1
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• pp.9-16
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• 1969

The sand drift movement at Young Il Bay area was tentatively investigated using Co-60 glass sand. Grain size and specific gravity of the glass sand which has originally contained natural cobalt, Co-59, was made similar to those of the real coastal sand, and was irradiated in a beam port of the reactor Triga Mark II to make the glass sand radioactive by the reaction of 59Co(n, r)60Co. The radioactive cobalt glass sand was deposited on the preselected point of sea bed, and, after a couple of weeks, the drift of sand was traced by means of specially designed water-proof G-M detector. Net counts at each point were plotted to figure out equicount lines and consequently such aspects as the direction of sand drift movement, the scope of distribution and the relative drift velocity etc. were indicated.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.470-483
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• 2003

As the amount of radioactive waste and related information to be managed are increasing, some organizations are trying or planning to computerize the management on radioactive waste. When we consider that information on safe management of radioactive waste should be used In association with national radioactive waste management project, standardization of data form and its protocol is required. Korea Institute of Nuclear Safety(KINS) will establish and operate nationwide integrated database in order to effectively manage a large amount of information on national radioactive waste. This database allows not only to trace and manage the trend of radioactive waste occurrence and in storage but also to produce reliable analysis results for the quantity accumulated. Consequently, we can provide necessary information for national radioactive waste management policy and related industry's planing. This study explains the database design which is the essential element for information management.

• The Korean Journal of Nuclear Medicine
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• v.29 no.3
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• pp.343-349
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• 1995

Background : For biological dosimetry of radiation exposure, both observing hematologic change and calculating Ydr by chromosomal analysis as biological indicators are widely used. However, due to the lack of studies on biological dosimetry of radiation dose absorbed in the body such as in the cases of radioactive iodine therapy, the maximal and safe dose is not well known, nor is the extent to which the body can safely endure radiation exposure. Purpose : To investegate the practical applicability of hematologic changes and Ydr as an indicator for estimating radiation exposure, to patients with thyroid diseases after doses of radioactive iodine. Material and Methods : 5 patients with hyperthyroidism and 35 patients who have had thyroid cancer operation were under treatment with radioactive iodine, changes in number of lymphocytes were tracked and Ydr was calculated for more than 2 months by chromosomal analysis in peripheral lymphocytes. Results ; 1) The number of lymphocytes began to decrease 2 weeks after doses of radioactive iodine, and reached the nadir after 6 and 8 weeks, then gradually recovered. 2) The nadir count of lymphocytes was reversely correlated with the administered dosage of radioactive iodine. 3) Ydr was generally stable between 2 and 8 weeks. 4) The maximal value of Ydr was correlated with the administered dosage of radioactive iodine. 5) Ydr value at the 2nd week increased with augmented dosage of radioactive iodine. 6) Ydr value at the 2nd week was correlated with fall of lymphocyte count. Conclusion : Patients must be closely observed, because temporary bone marrow suppression and slight chromosomal aberration can be produced by even generally used dosages of radioactive iodine for diagnosis and therapy. Maximal percent fall of lymphocyte count, Ydr at the 2 week interval and maximal Ydr can be used as the biological predictor of administered dosage of radioactive iodine.

• Defense and Technology
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• no.4 s.230
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• pp.38-47
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• 1998

레이다는 저고도 표적에 대한 탐지능력 ECCM 능력, 대방사유도탄에 대한 대처능력이 우수해야 하며, 동시다발 표적에 대한 탐지와 추적능력을 보유해야 하고 다기능 및 다목적 용도를 위해서 또는 시시각각으로 변하는 상황에 대처하기 위해서는 시스템의 융통성과 잠재능력이 커야 한다.

• 대한핵의학회:학술대회논문집
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• 1995.05a
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• pp.209-209
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• 1995

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.442-444
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• 2005

방사선을 센싱하는 센서들에는 어려 종류가 있으며, 그 센서에 따라서 감도나 센싱방식이 다양하다. 본 연구에서는 해상도가 높은 범용 CCD 센서를 이용하여 방사선을 검출하는데, 감도를 높이기 위해서 신실레이터라는 물질을 CCD CHIP 앞에 부착하였고, 들어오는 영상에서 방사선에 반응하여 생기는 백색량을 처리하여 방사선량을 측정할 수 있다는 것을 보여주고 있다. 또한 Panning을 하며 공간상에서 방사선이 가장 많이 나오는 포인터를 제시할 수 있다. 추후 스테레오 카메라 방식을 구현하여 방사선원까지의 거리 산출과 영상을 합성하여 입체화 시키는 연구도 진행할 예정이다. 논 연구의 결과물로 예기치 않은 방사선 사고의 경우 효과적인 사고처리에 활용될 수 있을 것이다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.43-48
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• 2018

Offset parabolic antenna have been widely used for satellite communication system. To locate feedhorn on antenna system, it requires arbitrary structure which forces to fix on system. However, arbitrary scatterer increases sidelobe level of elevation axis. To solve this problem, we need to predict which angle level is increased by arbitrary scatterer simply. Because conventional simulation method takes a long time to simulate parabolic antenna system and needs exclusive software. In this paper we can calculate sidelobe angle simply by using raytracing method, check coincidence between calculated and simulated result and show how arbitrary scatterer affects sidelobe lavel of elevation axis of offset parabolic antenna depending on angle and location of arbitrary structure.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.1-9
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• 2000

To understand the thermal characteristics around the piston ring gap ring gap positions and piston temperatures are measured simultaneously. The locations of piston ring gap are measured by the radio-tracer method and piston temperature are measured by a K-type thermocouple and scissors type linkage system. From these experiments following facts are clarified. Piston temperatures fluctuate according to the piston ring rotation. And the temperature fluctuation is mainly affected by top ring gap position irrelevant to the second ring fop position. If the top ring gap position increases and the temperature of top ring groove shows maximum value when top rin gap position coincide with temperature measuring point. The maximum amplitude of temperature fluctuation which is proportional to the blow by gas rate is around 12-15$^{\circ}C$.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.97-102
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• 2019

The GNSS(Global Navigation Satellite System) provides important information such as Position and Navigation, Timing(PNT) to various weapon systems in the military. as a result, applications that employ satellite navigation systems are increasing. therefore, a number of studies have been conducted to deceive the weapon systems that employ GNSS. GNSS spoofing denotes the transmission of counterfeit GNSS-like signals with the intention to produce a false position and time within the victim receiver. In order to deceive the victim receiver, spoofing signal should be synchronized with GNSS signal in doppler frequency and code phase, etc. In this paper, Civilian GPS L1 C/A spoofing signals have been evaluated and analyzed by SDR receiver.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.1
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• pp.79-88
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• 2001

The target such as aircraft operates flares to protect itself from the missile. In general, Infra-red(IR) flares that are hot bodies radiating energy considerably greater than it does, so cause the missile to guide the flare instead of the target. For a precise target tracking in spite of a presence of flares, therefore, the seeker should discriminate the target signal from various clutters including the flare and the background. In this paper, we simulated 2-color rosette scan seeker using IR and UV(UltraViolet) bands. In each wave band, we analyzed the radiant distributions of the target, the flare, and background. These results showed that a simultaneous process in two bands can detect precisely the target.