• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.7
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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.

• Radiation Oncology Journal
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• v.36 no.2
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• pp.85-94
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• 2018

Radiation-induced second malignancies (RISM) is one of the important late side effects of radiation therapy and has an impact on optimal treatment decision-making. Many factors contribute to the development of RISM such as age at radiation, dose and volume of irradiated area, type of irradiated organ and tissue, radiation technique and individual and family history of cancer. Exact mechanism of RISM is unknown. But nowadays, it is a growing concern in oncology because of the increased number of cancer survivors and efforts are being made to prevent or decrease the incidence of RISM. The primary search for articles was carried via Google Scholar and PubMed with keywords included 'radiation induced malignancies, second malignancies, and chemotherapy induced malignancies'. Additional papers were found through references from relevant articles. In this review article, we have discussed about the pathogenesis, factors contributing to RISM, screening and prevention strategies of RISM.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2781-2789
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• 2024

We developed lead gloves that minimize radiation dose to the operator's hands during interventional radiological procedures and that do not impede the operator's surgical capabilities. Existing lead gloves can protect the operator's hands by shielding radiation, but use of such gloves may impair preception sensitivity, resulting in a reduction in the operator's surgical ability. Accordingly, in this study, we developed modified lead gloves that can reduce radiation dose while maintaining operator sensitivity during procedures by modifying the operator's main surgical finger area in existing lead gloves. To evaluate the performance of developed modified lead gloves, radiation was applied in surgical conditions without gloves and with surgical gloves, lead gloves, and modified lead gloves. The radiation dose was evaluated for each condition. When the modified lead gloves were worn, the degree of shielding was similar to when conventional lead gloves were worn. Based on these results, if the operator wears modified lead gloves during interventional radiological procedures, they will protect the hands from radiation while maintaining physical sensitivity in the hands.

• Journal of Radiation Protection and Research
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• v.46 no.4
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• pp.213-217
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• 2021

Background: Radiation exposure can occur as a result of occupational activities utilizing sources of radiation. The average level of occupational exposure is generally similar to the global average, but some workers receive more than this. In this study, the occupational exposure data for workers in Korea to check the recent trend of radiation exposure. Materials and Methods: The data collection and analysis are carried out by two separate periods based on the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) survey. One is the year 2003 to 2014 for a recent survey, and the other is 2015 to 2019. All available data were collected by annual reports from radiation dose registry organizations. Results and Discussion: The annual dose over the record level to the total workers did not change much compared with the total increasing number of workers in this period. The dose to the nuclear fuel cycle field has a tendency to decrease. It resulted from the efforts of radiation dose reduction with high technology introduced to this area. Also, it is important result that the radiation dose to the workers in radiography is remarkably reduced. Conclusion: The number of radiation workers and average doses were analyzed for occupational categories in Korea. It still needs cooperative efforts between the dose registry organizations for the efficient dose management of Korean radiation workers.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.346-357
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• 2023

The purpose of this study is to suggest improvement plans for prevention regulations by reflecting the toxicity, fire and explosion effects of hazardous materials factories and surrounding areas using an off-site consequence assessment program. Regarding the effects of the hydrogen cyanide leak accident, which is the 1st petroleum of the 4th class flammable liquid, Areal Locations of Hazardous Atmospheres (ALOHA) program was used to compare and analyze the extent of damage effects for toxicity, overpressure, and radiation. As a result, the toxicity was analyzed to exceed 5km in the area with Acute exposure guideline level (AEGL)-2 concentration or higher, the overpressure was 103m in the range of 1 psi or more, and the radiant heat was analyzed to be 724m in the range of 2kw/m² or more. Toxicity and radiation affected the area outside the hazardous material storage area, but the overpressure was limited to the inside of the hazardous material storage area. Therefore, we propose to improve the safety management of hazardous materials by conducting a risk assessment for hazardous materials and reflecting the results in internal and external emergency response plans to prepare prevention regulations.

• Journal of Radiation Protection and Research
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• v.47 no.4
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• pp.226-236
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• 2022

Background: An effective communication strategy for reducing conflicts in South Korea has been designed through the analysis of public perception and communication variables on nuclear power under the conditions of rapidly changing nuclear power policies. Materials and Methods: This study conducted both qualitative research through group discussions based on social psychology and quantitative research through surveys. Results and Discussion: Nuclear power plant (NPP) area residents in favor of nuclear power indicated higher levels of communication, safety perception, and contribution than those against it. NPP area residents trusted the civilian expert groups (18.3%) and local government (17.3%) the most, while metropolitan city residents trusted the Nuclear Safety and Security Commission and the Korea Institute of Nuclear Safety (20.7%) the most. In determining nuclear power policy, both the NPP area residents (18.1%) and metropolitan city residents (17.1%) prioritized safety, health, and the environment. While metropolitan city residents thought that energy security and economic growth (16.4%) were important, NPP area residents thought the current issue of spent fuel rods (14.1%) to be important. Conclusion: It is necessary for the nuclear power industry to have and actively implement communication and conflict resolution strategies based on the patterns obtained in the study results.

• 전기의세계
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• v.14 no.3
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• pp.28-33
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• 1965

This experiment is based on "the feasible improvement studies for an eliminating device of the static electricity which applies the ionizing effect of beta radiation." In order to accomplish this object, the following problems were necessarily considered to investigate and to determine. The efficiency of the elimination of static electricity was determined by means of measuring the ion current between electrically charged plates with micro-ammeter. The effects of various factors, i.e., the distance between charged plate and radiation source, the activity of radiation source, the electric otential and the area of the charged plate, the shape of the source housing, the lining of backscattering material (Pb) on the source housing surface and blowing of ionized air, on the static electricity eliminating efficiency were studied. The beta radiation sources used in this experiment were S$^{35}$ and Sr$^{90}$ -Y$^{90}$ . It was revealed that ion current increased with source activity, the electric potential and area of the plates, the lead (Pb) lining on the surface of the source housing and the velocity of the ionized air blowing. As one could expect the S$^{35}$ was more effective to increase the ion current since it is known to be a higher specific ionization source than Sr$^{90}$ -Y$^{90}$ . The detailed result and performance of the eliminating device of the static electricity are described here.ibed here.

• Journal of radiological science and technology
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• v.46 no.6
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• pp.493-499
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• 2023

This study developed education contents of measuring spatial dose with virtual reality simulation and applied to students majoring radiological science. The virtual reality(VR) contents with measuring spatial dose rate in the radiation controlled area was developed based on the simulation from pilot study. In this simulation, the tube voltage and tube current can be set from 60 to 120 kVp in 10 kVp steps and 10 to 40 mAs in 10 mAs increments, and the distance from source can be set from 30 to 400 cm continuously. Iron and lead shields can be placed between the source and the detector, and shielding thickness can be set by 1 mm increments ranging from 1 to 20 mm. We surveyed to students for evaluating improvement of understanding spatial dose rate between before and after education by VR simulation. The survey was conducted with 5 questions(X-ray exposure factors, effects by distance from the source, effects from using shield, depending on material and thickness of shield, concept and measuring of spatial dose rate) and all answers showed significant improvement. Therefore, this VR simulation content will be well used in education for spatial dose rate and radiation safety environments.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.213-218
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• 2007

Purpose: To analyze retrospectively the outcome of postoperative radiation therapy with or without concurrent chemotherapy for curatively resected stage II pancreatic cancer with T3 or N1 disease. Materials and Methods: Between January 1996 and December 2005, twenty-eight patients completed adjuvant radiation therapy at Ajou University Hospital. The patients had either pathologic T3 stage or N1 stage. The radiation target volume encompassed the initial tumor bed identified preoperatively, resection margin area and celiac nodal area. In the case of N1 patients, the radiation field extended to the lower margin of the L3 vertebra for covering both para-aortic lymph nodes bearing area. The median total radiation dose was 50 Gy. Ten patients received concurrent chemotherapy. Results: Thirteen patients (46%) showed loco-regional recurrences. The celiac axis nodal area was the most frequent site (4 patients). Five patients showed both loco-regional recurrence and a distant metastasis. Patients with positive lymph nodes had a relatively high probability of a distant metastasis (57.1%). Patients that had a positive resection margin showed a relatively high local failure rate (57.1%). The median disease-free survival period of all patients was 6 months and the 1-and 2-year disease free survival rates were 27.4% and 8.2%, respectively. The median overall survival period was 9 months. The 2-and 3-year overall survival rates were 31.6% and 15.8%, respectively. Conclusion: The pancreatic cancer patients with stage II had a high risk of local failure and a high risk of a distant metastasis. We suggest the concurrent use of an effective radiation-sensitizing chemotherapeutic drug and adjuvant chemotherapy after postoperative radiation therapy for the treatment of patients with stage II pancreatic cancer.

• Journal of Korean society of Dental Hygiene
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• v.16 no.2
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• pp.215-224
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• 2016

Objectives: The purpose of the study was to investigate the related factors of performance of radiation safety management in dental hygienists. Methods: A self-reported questionnaire was completed by 183 dental hygienists using dental radiography in 110 dental clinics in G area by convenience sampling methods. The questionnaire consisted of general characteristics of the subjects, radiation-related characteristics, and performance and management of radiation safety. Results: Performance score of radiation safety management was $35.71{\pm}12.49$ in dental hygienists. The performance score of radiation safety management were associated with sex, numbers of dental hygienists, the average numbers of admitted patients per day, the total clinical experience, existence of manual for radiation safety management and perceived need for education of radiation safety management. Conclusions: The performance score was relatively low. The performance score was associated with radiation safety manual and safety equipment. The preparation of radiation protective environment and equipment will improve the performance of radiation safety management in dental hygienists.