• The korean journal of orthodontics
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• v.37 no.6
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• pp.391-399
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• 2007

Three-dimensional approaches for the diagnosis and analysis of the dentofacial area are becoming more popular in accordance with the development of cone-beam CT (CBCT). The purposes of this study were to evaluate the reliability of cephalometric measurements of lateral cephalograms generated from a CBCT image by making comparisons with the traditional digital lateral cephalogram, and to evaluate the possibility of the clinical application of CBCT generated cephalogram images. Methods: Twenty patients whose external auditory meatus could be identified in the CBCT image were selected, and both CBCT and digital cephalograms were taken. Differences between the measurements of both cephalograms were tested by paired t-test. Results: Among the 22 measurements used, only U1-FH, Mx6 to PTV, and maxillomandibular difference showed statistically significant differences between the CBCT generated cephalogram and the digital cephalogram. Conclusions: The results suggest that the CBCT generated cephalogram can be used for some cephalometric measurements not requiring porion, PTV, condylion as a landmark (SNA, SNB, U1 to SN, IMPA, interincisal angle, etc.).

• Journal of radiological science and technology
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• v.40 no.1
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• pp.7-12
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• 2017

The study was performed to investigate the bacteriological contamination of portable digital radiography system and their detectors in a university hospital. CNS and VRE were detected in the samples collected from vinyl cover on detectors used for the infection control patients. On the other hand, no bacteria was detected in the samples collected from detectors with vinyl cover removed. In the series of imaging of patients from general wards, no bacteria was detected from the patient 1. However, CNS was detected from the patients 2 and 3, CNS and Enterococcus faecalis detected from the patient 4, CNS and Enterococcus casseliflavus detected from the patient 5, and CNS, Enterococcus casseliflavus, and Klebsiella pneumoniae all detected from the patient 6. CNS and Enterococcus faecium were detected in the controller handle of collimator. Also, CNS was detected from the handle of detector and exposure switch. In the treatment gloves of the radiological technologist after the imaging, CNS, Enterococcus gallinarum, and Klebsiella pneumoniae were detected. Therefore, it is recommended for DR portable to take images after sterilizing the detector after taking each image and to use disposable vinyl covers on detectors to remove after imaging. And treatment gloves must be changed after each imaging. Also, hospital infection via portables must be prevented by complete sterilization of the controller handles of collimator which are in frequent contact during imaging and infection education of employees.

• Journal of Conservation Science
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• v.27 no.2
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• pp.127-134
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• 2011

In this study, there has been investigated the simulation of irradiation dose using Monte Carlo methodology and experimental substantiation for the biological control of wooden cultural property. In the evaluation of fungal contamination on wooden cultural property, Dongyae, from exhibition storage, Aureobasidium pullulans was mainly identified. But these microorganisms were completely inactivated by 20 kGy gamma irradiation. For dosimetry simulation of Dongyae, Monte Carlo methodology with MCNP was used. The real dosimetry was measured using alanin dosimeters (at 7 different points on the front plan and 7 points on the back plan). Simulated and experimental results are compared and good agreement is observed. These result shows that irradiation can offer biologic control of wooden cultural property by optimal irradiation dose through high penetration power and Monte Carlo simulation.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.2
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• pp.91-101
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• 2007

In this study, domestic regulatory requirement was investigated for self-disposal of concrete waste from nuclear fuel processing facility. And after self-disposal as landfill or recycling/reuse, the exposure dose was evaluated by RESRAD Ver. 6.3 and RESRAD BUILD Ver.3.3 computing code for radiological assessments of the general public. Derived clearance level by the result of assessments for the exposure dose of the general public is 0.1071Bq/g (3.5% enriched uranium) for landfill and $0.05515Bq/cm^2$ (5% enriched uranium) for recycling/reuse respectively. Also, residual radioactivity of concrete waste after decontamination was investigated in this study. The result of surface activity is $0.01Bq/cm^2\;for\;{\alpha}-emitter$ and the result of radionuclide analysis for taken concrete samples from surface of concrete waste is 0.0297Bq/g for concentration of $^{238}U$, below 2w/o for enrichment of $^{235}U$ and 0.0089Bq/g for artificial contamination of $^{238}U$ respectively. Therefore, radiological hazard of concrete waste by self-disposal as landfill and recycling/reuse is below clearance level to comply with clearance criterion provided for Notice No.2001-30 of the MOST and Korea Atomic Energy Act.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.267-277
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• 2016

For the decommissioning of a nuclear power plant, a site characterization and final status survey require a site-specific suite of radionuclides that could potentially still be present in the site during or after the decontamination processes. The United States Nuclear Regulatory Commission (U.S. NRC) requires a Decommissioning Technical Base Document (DTBD) along with a Site Characterization and Historical Site Assessment (HSA) from the utility for decommissioning to proceed. Both the DTBD and HSA are preliminary components of the Radiological Site Survey investigation process and should be included in the final License Termination Plan (LTP) for site release and reuse consideration from the U.S. NRC and the utility company. This study reviews the United States Nuclear Power Plants (U.S. NPPs) decommissioning cases and is especially focused on the methodologies used for determining a site-specific suite of radionuclides before and during the site characterization and final status surveys. In 2017, Kori-1 will be ready for decommissioning and related preparations are ongoing, this review will help Korea to prepare regulatory guidelines and give technical background for the safe and successful decommissioning of NPPs.

• Journal of radiological science and technology
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• v.11 no.1
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• pp.71-77
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• 1988

To improve the storage method for kimchi, optimal ripening kimchi was irradiated with doses of 1, 3, 5kGy Co-60gamma radiation, followed by the microbiological, physicochemical and senosory evaluations during storage at $5^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total lactobacilli (anaerobe) increased. The above, total aerobic and lactobacilli were reduced by 1 to 3 log cycles with irradiation and at the 90th day after storage the number of total lactobacilli remained $1.30{\times}10^{8}$ per ml in 3 kGy irradiated group. Irradiation treatment at 3 kGy sterilized coliforms and molds contaminating the sample as the level of $2.0{\times}10^{4}$ per ml and $5.4{\times}10^{2}$ per ml respectively and no apparent growth was observed in both control and 1 kGy irradiated groups after 20 days of storage. The population of yeast, $3.5{\times}10^{3}$ per ml initially, increased steadily during kimchi storage and at 90 days of storage the number was shown to be $5.6{\times}10^{4}$ per ml and $6.5{\times}10^{2}$ per ml in control and 3 kGy irradiated groups, respectively. 2. In the physicochemical changes during kimchi storage, pH, acidity and volatile acid of non-irradiated control at the 45th day after storage were 4.0, 0.7% and 0.066%, while those of 3 kGy irradiated group were 4.2, 0.59 and 0.06% at the 90th day of storage, respectively. The reducing sugar content of all stored samples changed inversely total acidity content, indicating irradiation delayed the changes of them. The amount of ascorbic acid decreased gradually with the storage time and irradiation dose increase. Textural parameters of 3 kGy irradiated group were superior to those of other groups at the latter stage of storage. 3. Sensory evaluations showed that 3 kGy irradiation was the optimum dose level to extend the shelf-life of kimchi more than two months as compared to control.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.21-27
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• 1987

ABS1'RACT-Comparative effects of gamma irradiation and ethylene oxide treatment on the sterilization, and physicochemical and sensory quality of dried marine products(shrimp, anchovy) were investigated. Population of mesophilic total bacteria, aerobic spores and tolerant bacteria of samples were $10^{3}-10^{7}/g,\;10^{7}\;to \;10^{4}/g\;and\;10^{2}\;to\;10^{6}/g$, respectively. Coliforms and molds were found only in dried shrimp as $10^{2}/g$. Mesophilic total bacteria, aerobic spores and acid tolerant bacteria were reduced by over 2 to 4 log cycles with irradiation of 5 to 7 kGy and they were completely sterilized by irradiation dose of 7 to 10 kGy. $D_{10}$ value of mesophilic total bacteria of samples ranged from 1.53 to 2.73 kGy. Coliforms and molds were sterilized at 5 to 7 kGy irradiation but ethylene oxide treatment proved insufficient to eliminate the microorgainsms. An optimum dose of irradiation was less detrimental than ethylene oxide treatment to phpicochemical properties of the samples, such as the pH, TBA value, TMA-N, amino acids, minerals and color difference. Sensory quality after three months of storage showed that the overall acceptability of irradiated sample was higher than that of the non treated control as well as ethylene oxide treated samples.amples.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.237-246
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• 2016

This study is therefore aimed at measuring the surface dose rate and the spatial dose rate in and outside the radionuclide facility in order to ensure safety of the patients, radiation workers and family care-givers in their use of such equipment and to provide a basic framework for further research on radiation protection. The study was conducted at 4 restrooms in and outside the radionuclide facility of a general hospital in Incheon between May 1 and July 31, 2014. During the study period, the spatial contamination dose rate and the surface contamination dose rate before and after radiation use were measured at the 4 places-thyroid therapy room, PET center, gamma camera room, and outpatient department. According to the restroom use survey by hospitals, restrooms in the radionuclide facility were used not only by patients but also by family care-givers and some of radiation workers. The highest cumulative spatial radiation dose rate was 8.86 mSv/hr at camera room restroom, followed by 7.31 mSv/hr at radioactive iodine therapy room restroom, 2.29 mSv/hr at PET center restroom, and 0.26 mSv/hr at outpatient department restroom, respectively. The surface radiation dose rate measured before and after radiation use was the highest at toilets, which are in direct contact with patient's excretion, followed by the center and the entrance of restrooms. Unsealed radioactive sources used in nuclear medicine are relatively safe due to short half lives and low energy. A patient who received those radioactive sources, however, may become a mobile radioactive source and contaminate areas the patient contacts-camera room, sedation room, and restroom-through secretion and excretion. Therefore, patients administered radionuclides should be advised to drink sufficient amounts of water to efficiently minimize radiation exposure to others by reducing the biological half-life, and members of the public-family care-givers, pregnant women, and children-be as far away from the patients until the dose remains below the permitted dose limit.

• Tuberculosis and Respiratory Diseases
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• v.58 no.6
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• pp.619-623
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• 2005

Blastomycosis is a systemic pyogranulomatous disease that is caused by a thermally dimorphic fungus, Blastomyces dermatitidis. it's the disease is endemic in the south-eastern and south central states of the USA, which border the Mississippi and Ohio Rivers, the mid-western states and Canadian provinces bordering the Great Lakes as well as in a small area of New York and Canada adjacent to the St. Lawrence River. We encountered a case of blastomycosis, representing as a pulmonary manifestation after traveling around a nonendemic area and report it with a brief review of the relevant literature.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.4
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• pp.259-267
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• 2021

Peri-implantitis, in which inflammation caused by plaque and biofilm on the implant surface spreads to the hard tissue, can be treated by decontamination of the implant surface and reconstruction of the lost hard tissue through surgical methods. We have described the management of 3 peri-implantitis cases by decontamination of the implant surface using a round titanium brush and regenerative therapy. All cases showed clinical improvements, and no further radiographic bone loss was observed during a 2-year follow-up. This treatment method can be effective for clinical improvement and bone regeneration. However, a longer follow-up period is necessary to support these outcomes.