• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.403-406
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• 1999

For a man's approaching limitation in radiation environment, all work must be performed with remoted system to ensure worker's safety and reliability from radiation damage. The remoted system is mostly used in visual observation CCTV system. In high radiation environment of unclear power plant, RI(Radio-isotope) facility, medical radiation treatment facility must be used to radiation tolerant CCTV cameras for radiation damage. We have studied a radiation basic performance of camera components and CCTV cameras to develop radiation tolerant CCTV cameras. As a result, we are able to design a radiation tolerant camera of 108 rad total dose.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.855-857
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• 1999

Lymphangioma(or cystic hygroma) of the chest wall is rare case. We experienced one such case in a 16-year-old girl who complained of a large recurrent mass on her right upper post erolateral chest wall which had developed several years ago. The diagnosis was made following a physical examination, chest magnetic resonance imaging(MRI), and radio isotope (RI) lymphangiogrphy and was confirmed by a histopathological examination. We performed total excision of the lesion followed by a repeated sclerosing therapy with intralesional injection of Vibramycin.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.66-73
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• 2006

Monoclonal antibodies are designed to bind specifically to certain antigen, give therapeutic effect to the target and to be produced in large scale with homogeneity. The monoclonal antibodies conjugated with radionuclide can deliver therapeutic irradiation to the target, and showed successful results in certain malignancies, which is known as radioimmunotherapy. The target-to-background ratio depends on the antigen expression in the target and normal tissues, which is related to the therapeutic efficacy and toxicity in radioimmunotherapy. For the solid tumor beta-ray energy should be high, but lower beta energy is better for the hematological malignancies. I-l31 is widely used in thyroid cancer with low cost and high availability. Labeling monoclonal antibody with I-131 is relatively simple and reproducible. Some preclinical data for the I-131 labeled monoclonal antibodies including acute toxicity and efficacy are available from already published literatures in KIRAMS, physician sponsored clinical trial protocols using Rituximab, KFDA approved anti-CD20 chimeric monoclonal antibody and I-131 were approved by KFDA and currently are ongoing.

• Nuclear Engineering and Technology
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• v.4 no.2
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• pp.83-89
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• 1972

The contents of the individual lanthanide elements are determined by neutron activation using a new comparator technique, which employs the short-lived radio-isotope of 56Mn as a neutron flux monitor. The total rare earths are separated as a group from the monazite sample before irradiation. After irradiation the rare earths are separated from each other by gradient elution with ammonium alpha-hydroxyisobutyrate using a cation-exchange column. The contents of 14 individual rare earths, from lutetium to lanthanum, are deter-mined.

• Journal of the Korean association of regional geographers
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• v.22 no.2
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• pp.439-449
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• 2016

Understanding the variability of the monsoon system requires information about the changes in the past. We revealed the Mid- and Late-Holocene paleo-climate changes and Asian monsoon variations in Korea by the speleothem records from Pyeongchang. To this, we used thicknesses of growth laminae, stable-isotope analysis (carbon, oxygen), and radio-carbon age dating. The speleothem grew between ~4580 yr BP to ~660 yr BP and we identified several weak AM(Asian monsoon) events, such as Middle Bronze Age Cold Epoch, Iron Age Cold Epoch, and Dark Age Cold Period. These events might have occurred relatively early compared to those of other studies.

• Nuclear Engineering and Technology
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• v.27 no.5
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• pp.767-774
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• 1995

Behavior of radionuclides such $^{60}$ Co, $^{54}$ Mn and $^{137}$ Cs in the incineration Process was Studied by trial burns of simulated wastes with radio-isotope tracers. Behavior of nonvolatiles, $^{60}$ Co and $^{54}$ Mn, was similar to that of particulate matters in the process. Decontamination factors(DFs) for $^{60}$ Co and $^{54}$ Mn were 4.7$\times$10$^{5}$ and 6.2$\times$10$^{5}$ , respectively. Behavior of semivolatile radio-isotope, $^{137}$ Cs, was temperature dependent. DFs for $^{l37}$Cs at In different incineration temperature of 85$0^{\circ}C$ and $700^{\circ}C$ were 2.8$\times$10$^3$ and 2.6$\times$10$^4$, respectively. Trial bums of dry active waste(DAW) transported from nuclear power station(NPS) Kori 3,4 were also performed. DF for gross $\beta$/${\gamma}$ radioactivity in DAW was 1.1$\times$10$^{5}$ . This was a little higher than the estimated value, which was calculated from the tracer test results and nuclides distribution in the DAW. Average emission concentration was 0.019 Bq/N $m^3$, which could meet the maximal permissible concentration(MPC) in stack emission.n.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.243-244
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• 2013

Over the past 15 years, several groups have incorporated radio-frequency quadrupole (RFQ) based instruments before the accelerator in accelerator mass spectrometry (AMS) systems for ion-gas interactions at low kinetic energy (＜40 eV). Most AMS systems arebased on a tandem accelerator, which requires negative ions at injection. Typically, AMS sensitivity abundance ratios for radioactive-to-stable isotope are limited to Xr/Xs ＞10^-15, and the range of isotopes that can be analyzed is limited because of theneed to produce rather large negative ion beams and the presence of atomic isobaric interferences after stripping. The potential of using low-kinetic energy ion-gas interactions for isobar suppression before the accelerator has been demonstrated for several negative ion isobar systems with a prototype RFQ system incorporated into the AMS system at IsoTrace Laboratory, Canada (Ontario, Toronto). Requisite for any such RFQ system applied to very rare isotope analysis is large transmission of the analyte ion. This requires proper phase-space matching between the RFQ acceptance and the ion beam phase space (e.g. 35 keV, ${\varphi}3mm$, +-35 mrad), and the ability to control the average ion energy during interactions with the gas. A segmented RFQ instrument is currently being designed at Korea Institute for Science and Technology (한국과학기술연구원, KIST). It will consist of: a) an initial static voltage electrode deceleration region, to lower the ion energy from 35 keV down to ＜40 eV at injection into the first RFQ segment; b) the segmented quadrupole ion-gas interaction region; c) a static voltage electrode re-acceleration region for ion injection into a tandem accelerator. Design considerations and modeling will be discussed. This system should greatly lower the detection limits of the 6 MV AMS system currently being commissioned at KIST. As an example, current detection sensitivity of 41Ca/Ca is limited to the order of 10^-15 while the 41Ca/Ca abundance in modern samples is typically 41Ca/Ca~10^-14 - 10^-15. The major atomic isobaric interference in AMS is 41K. Proof-of-principal work at IsoTrace Lab. has demonstrated that a properly designed system can achieve a relative suppression of KF3-/41CaF3- ＞4 orders of magnitude while maintaining very high transmission of the 41CaF3- ion. This would lower the 41Ca detection limits of the KIST AMS system to at least 41Ca/Ca~10^-19. As Ca is found in bones and shells, this would potentially allow direct dating of valuable anthropological archives and archives relevant to our understanding of the most pronounced climate change events over the past million years that cannot be directly dated with the presently accessible isotopes.

• The Korean Journal of Nuclear Medicine
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• v.3 no.1
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• pp.41-49
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• 1969

742 cases of thyroid diseases treated at Radio-isotope Clinic, Seoul National University Hospital since October 1965 through July 1968 were analyzed. The patients were classified according to eye findings, as to Infiltrative, Non-infiltrative and No ophthalmopathy. Correlations between ophthalmological findings and symptoms, BMR values and $^{131}I$ uptake rate as well as response to medical treatment were carefully reviewed. Results obtained were as follows: 1. Among goitrous patients 44.5% with infiltrative ophthalmopathy, 24.1% with non-infiltrative ophthalmopathy totaling 68.6% of patients with one or more eye findings were found. Exophthalmos (44%) and visual disturbances (44%) comprised the highest incidence among eye signs. Most frequent eye symptoms were lid swelling (17.1%). 2. Female patients were predominant(91%). 3. Of cases with hyperthyroidism, after treatment with antithyroid drugs and radio-iodine therapy, general symptoms were improved in over 74%, whereas ophthalmopathy was not changed and in some cases the eye signs were aggravated. This tendency was more apparent in infiltrative ophthalmopathy. 4. Significant correlations between exophthalmos, BMR values and $^{131}I$ uptake rate were found. Among the patients of same degree of exophthalmos, BMR values and $^{131}I$ uptake rate showed the highest in non-infiltrative ophthalmopathy, moderate in infiltrative ophthalmopathy and the lowest in no ophthalmopathy.

• Biomedical Engineering Letters
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• v.8 no.4
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• pp.383-392
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• 2018

For prompt gamma ray imaging for biomedical applications and environmental radiation monitoring, we propose herein a multiple-scattering Compton camera (MSCC). MSCC consists of three or more semiconductor layers with good energy resolution, and has potential for simultaneous detection and differentiation of multiple radio-isotopes based on the measured energies, as well as three-dimensional (3D) imaging of the radio-isotope distribution. In this study, we developed an analytic simulator and a 3D image generator for a MSCC, including the physical models of the radiation source emission and detection processes that can be utilized for geometry and performance prediction prior to the construction of a real system. The analytic simulator for a MSCC records coincidence detections of successive interactions in multiple detector layers. In the successive interaction processes, the emission direction of the incident gamma ray, the scattering angle, and the changed traveling path after the Compton scattering interaction in each detector, were determined by a conical surface uniform random number generator (RNG), and by a Klein-Nishina RNG. The 3D image generator has two functions: the recovery of the initial source energy spectrum and the 3D spatial distribution of the source. We evaluated the analytic simulator and image generator with two different energetic point radiation sources (Cs-137 and Co-60) and with an MSCC comprising three detector layers. The recovered initial energies of the incident radiations were well differentiated from the generated MSCC events. Correspondingly, we could obtain a multi-tracer image that combined the two differentiated images. The developed analytic simulator in this study emulated the randomness of the detection process of a multiple-scattering Compton camera, including the inherent degradation factors of the detectors, such as the limited spatial and energy resolutions. The Doppler-broadening effect owing to the momentum distribution of electrons in Compton scattering was not considered in the detection process because most interested isotopes for biomedical and environmental applications have high energies that are less sensitive to Doppler broadening. The analytic simulator and image generator for MSCC can be utilized to determine the optimal geometrical parameters, such as the distances between detectors and detector size, thus affecting the imaging performance of the Compton camera prior to the development of a real system.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.262-262
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• 2012

A multi-purpose cyclotron, MC50 has been operated to provide multi-ions of proton, deuteron and alpha at Korea Institute of Radiological and Medical Sciences (KIRAMS). Neutron is also produced through the (p,n) nuclear process with a Be target. However, a wide spectrum of current of ions is requested by beam users for carrying their various application fields. Therefore a simulation study is requested on the design of an axial injection system for high current proton and alpha beam extraction for radio-isotope productions and scientific researches. The purpose of this study is seeking a relatively simple method for the MC50 having higher alpha beam capability and also improving proton and deuteron beams currently used. We are considering two possibilities to improve the internal ion source and to install a new external axial injection system. The external injection system will be consisted of an Einzel lens, a steering magnet, a buncher, and a glazer lens placed in front of an inflector, which is located at the center of the main magnet.