• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.429-436
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• 2012

In this paper, an RFID system for the automatic preparation system of positron emission tomography (PET) radiopharmaceuticals is developed. Since the preparation system uses radioactive isotope, the preparation system is generally placed in lead-shielded hot-cell. Disposable cassettes including tubes and valves are used in the preparation system, since they are easily contaminated by radioactivity during preparation of radiopharmaceuticals. Currently, a system for preventing re-use of the cassette and managing the information about the preparation precess and result independently from the PC which control the preparation system is highly required for preventing danger from the radiation accident. Since RFID can store and re-write relatively large amount of information, it is suitable for the purpose. However, it is hard to read multiple cassettes' information using antennas installed on the metallic surfaces with current RFID systems. For the problem, we improve RFID system in two directions. First, the interface of the RFID reader is changed then it is possible that multiple readers can be daisy-chained. Also, antenna is tuned while inserting in a metallic coated antenna case, then the effect from the metallic surface of the preparation system is minimized. The test result using the developed system shows that the developed RFID system can read multiple tags using the antennas which are attached on the metallic surface.

• Journal of the Korean Society of Radiology
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• v.1 no.3
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• pp.35-40
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• 2007

The purpose of this study was to investigate in S city of Chung-Nam using direction radiation Cervical spine among patient enforcing AP view, lateral view, total 113 subjects(40-year-old low)by target examine and got following as: 1) Distribution of age 14~40 years old 57 men (50.4%), woman 56subjects(49.6%)be, and age group 30~40year old 80subjects(70.8 %), 20~29year old 27subjects(23.9%). 2) It appeared most by 81subjects(71.7%) that can not know cause though traffic accident, misstep, cause ignorantness were investigated to revealed by the chronic 87subjects(77%) appeared by thing which statistical significance is with occurrence cause. 3) 20 Among whole 113subjects 20~29years old 27 subjects(23.9%), 30~40years old 80 subjects(70.8%) manifestationacute form of a disease, the chronic all high distributionsee. 4) This investigator left shoulder region pain among 39 subjects whole 113 subjects (left to direction that could know that is each main pain in 34.5 %), cervical vertebral portion upside 31 subjects(27.4%), both shoulder region pain 20 subjects(17.7%), and becomes left side scoliosis 62 subjects(54.9%)by the most frequencies appear. 5) Appeared antespondylolisthesis by all curve 48 subjects(42.5 %) in curve direction and at Systolic blood pressure from 160mmHg to all 19 subjects (before total 69 subjects (61.0 %) at 16.8 %), Diastolic blood pressures curve 31 subjects(27.4 %) by 100 mmHg appear.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.3
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• pp.321-328
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• 2019

The detection performances of the NaI(Tl), $LaBr_3$(Ce) and $CeBr_3$ scintillation detectors, which can be used to rapidly evaluate the major artificial radionuclides deposited on the soil surface in a nuclear accident or radiological emergency, were compared. Detection performance was assessed by calculating the minimum detectable activity (MDA). The detection efficiency of each detector for artificial radionuclides was semi-empirically determined using mathematical modelling and point-like sources having certified radioactivity. The background gamma-ray energy spectrum for MDA evaluation was obtained from relatively wide and flat grassland, and the MDA values of each detector for the major artificial radionuclides that could be released in nuclear accidents were calculated. As a result, the relative MDA values of each detector regarding surface deposition distribution at normal environmental radiation level were evaluated as high in the order of the NaI(Tl), $LaBr_3$(Ce), and $CeBr_3$ detectors. These results were compared based on each detector's intrinsic and measurement environment background, detection efficiency, and energy resolution for the gamma-ray energy region of the radionuclide of interest.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.4
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• pp.331-341
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• 2020

Objectives: This study was conducted to evaluate perceptions of safety and risk among Korean industrial hygienists and the change between before and after the Sewol Ferry Disaster in 2014. Two surveys with questionnaires composed of 51 questions were completed by attendees of the Korea Industrial Hygiene Association(KIHA) conference. Methods: One was conducted at the 2013 KIHA Fall Conference(N=181) and the other was from the 2014 KIHA Summer Conference(N=123). Between these two surveys was the Sewol Ferry Disaster on April 14, 2014, which was believed to seriously affect safety and risk perceptions in Korea. Results: It was revealed that industrial hygienists' awareness of safety rules strengthened after the Sewol Ferry Disaster(p<0.05). It was apparent that people over the age of 30 were more sensitive to social safety. There was no significant difference in the evaluation and attitude regarding governmental safety policy between the years of 2013 and 2014. The credibility of public organizations responsible for the disaster management system decreased. The self-evaluation of respondents' safety level also decreased. This trend shows mainly in the younger generation. It was evaluated that the overall social safety level decreased and the anxiety level increased. The score on social safety on a ±5 Likert scale was 0.68 in the 2013 survey and -0.33 in the 2014 survey(p<0.05). It was reported that the most serious threat factors for accident or disaster were 'building collapse > illegalities and corruption > side effects of radiation therapy >accidents in normal activity > occupational disease,' in order. They picked 'safety ignorance > hurry-up habits and culture > focusing on short-term benefit > easy-going attitude > insufficient safety education' for the causes of low social safety levels in 2013. In 2014, they were 'safety ignorance > easy-going attitude > focusing on short-term benefit > insufficient safety education > hurry-up habits and culture'. Conclusions: This study has some limitations because it was originally not designed to survey attitudes prior to the Sewol Ferry disaster in 2013. In addition, the survey targets are industrial hygienists who are familiar with occupational disease and injury.

• Journal of the Korean Institute of Gas
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• v.28 no.1
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• pp.73-84
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• 2024

In this study, a quantitative risk impact assessment is performed using an ALOHA program to identify the risks when applying ammonia as fuel for combined cycle power plants as one of the solutions of climate change. The worst and the alternative accident scenarios are established for the Sejong combined cycle power plant and the effective ranges are calculated in terms of flammability, thermal radiation, overpressure and toxicity. The analysis results show that the toxic risk is the most critical and the effective distance is highly proportional to the mixing ratio of natural gas and ammonia by showing the Pearson's correlation coefficient over 98% as 0.991, 0.987 and 0.989 for the Level Of Concern(LOC)-1, LOC-2 and LOC-3, respectively. In addition, the coefficients of linearity for LOC-1, LOC-2 and LOC-3 are calculated to 133, 70 and 29, respectively so it can be confirmed that the effective distance increases as the criterion decreases.

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.223-230
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• 2015

The objective of this study is to identify the radionuclide distribution in public water by carrying out the analysis of artificial radionuclides($^{134}Cs$, $^{137}Cs$, $^{239+240}Pu$), natural radionuclide($^{210}Pb$) and TOC in the lake Euiam sediment in Chuncheon, South Korea. The $^{134}Cs$ concentration in all lake sediments showed below MDA values, and the $^{137}Cs$ concentration in lake sediment were ranged from MDA to $8.79Bq{\cdot}kg^{-1}-dry$. The $^{137}Cs$ concentrations in surface sediment were reported to be 2.4 to $4.2Bq{\cdot}kg^{-1}-dry$. The lowest concentration of $^{137}Cs$ was reported at St. 4 and the highest concentration was reported at St. 3, respectively. The $^{239+240}Pu$ concentration in lake sediment were ranged from 0.049 to $0.47Bq{\cdot}kg^{-1}-dry$. The lowest concentration was reported at St. 2 and the highest concentration was reported at St. 3. The correlation(r) between the $^{239+240}Pu$ concentration and $^{137}Cs$ concentration in lake sediment presented higher values (0.54 to 0.97) and this suggests the behavior and origin of $^{137}Cs$ is identical to the $^{239+240}Pu$ in the sediment. The $^{134}Cs$ concentration below MDA value and the $^{239+240}Pu/^{137}Cs$ ratio(mean value of 0.041) indicated that the artificial radionuclides in the sediment were originated from global fallout by the atmospheric testing of nuclear weapons conducted by former USSR and U.S.A, but not from the Fukushima Daiichi NPP accident. The sedimentation rate derived from $^{210}Pb$ age-dating method at St. 2 is calculated to be $0.31{\pm}0.06cm{\cdot}y^{-1}$. This value is similar to the value ($0.41{\pm}0.05cm{\cdot}y^{-1}$) estimated from the $^{137}Cs$ maximum peak produced from early 1960's. The content of TOC in lake Euiam sediments varied from 0.20 to 13.01%. While the highest correlation between TOC and $^{137}Cs$ concentration in the sediment were found at St. 1, the others presented the low correlation.

• The Journal of the Korean bone and joint tumor society
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• v.20 no.1
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• pp.14-21
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• 2014

Purpose: To analyze the clinical features and treatment outcome of Langerhans' cell histocytosis. Materials and Methods: From August 1996 to June 2013, 28 patients who histologically proven with LCH were analyzed of medical records, radiography, pathologic character retrospectively. Results: A total of 28 cases of LCH including 22 child has been reported. Onset age was 0.6 to 51 years old, occurred in the average age was 14.8 years. Follow-up period was 6 months to 134 months average was 44.6 months. The M:F ratio was 2.5:1. The initial symptoms was pain in 18 cases, 5 cases of pathologic fracture, 3 case of palpable mass, 1 case of discovered by accident in radiography, 1 case of torticollis. In radiological examination osteolysis was seen all cases, 7 cases showed a periosteal reaction, 1 case showed soft tissue extension. Clinical type of all cases were eosinophilic granuloma. 25 cases were classified as unifocal disease and 3 cases were multifocal single systemic diseases. In all cases, incisional biopsy was performed. After histologic confirmed, 14 cases was treated with curettage or surgical excision of the lesion and the other 14 cases were followed up without treatment. There is no death during follow up period. 11 cases has no radiological improvement after 3-6 months observation, intralesional steroid injection was performed. Conclusion: Patients with LCH who has rapid systemic onset is very rare, so if you meet the young children who suspected LCH, you shoulder avoid the examination which cause excessive radiation exposure to the young patient. In order to confirm the diagnosis of disease, biopsy is needed. Close observation after confirmed by histological method will bring the satisfactory results. But the patients who had pathologic fracture or wide bone destruction already may need curettage and bone grafting to lesion or internal fixation. The lesion which has no radiological improvement after 3-6 months observation or appear with pain interferes daily life may need local steroid injection as a good treatment.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.164-168
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• 1999

For investigating transfer factors of $^{137}Cs$ in the arable land of Korea, mature crop plants and topsoils were collected from paddy and upland fields located at 33 areas of the country and $^{137}Cs$ concentrations were measured by ${\gamma}-spectrometry$. The $^{137}Cs$ concentrations in soil were in the range of $0.7{\sim}17.7$ Bq/kg-dry in the paddy fields and $1.2{\sim}27.8$ Bq/kg-dry in the upland fields. The $^{137}Cs$concentrations in hulled seed, detected for 12 areas only, were in the range of $0.019{\sim}0.111$ Bq/kg-dry and those in Chinese cabbage, detected also for 12 areas only, were in the range of $0.012{\sim}0.066$ Bq/kg-fresh. Soil-to-plant transfer factors of $^{137}Cs$ were in the range of $1.2{\times}10^{-3}{\sim}1.1{\times}10^{-2}$ for hulled seed and $6.8{\times}10^{-4}{\sim}1.7{\times}10^{-2}$ for Chinese cabbage. Inboth plant stuffs, the factor tended to decrease with increasing soil organic matter or cation exchange capacity and, in hulled seed, it tended to increase with increasing soil clay content. No statistical significance was, however, found in all those relationships. Present results can be utilized for estimating radiation risk resulting from the food consumption by Korean people and deciding agronomical counter-measures at the time of an nuclear accident.