• ALGAE
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• v.31 no.4
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• pp.403-414
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• 2016

The use of ionizing radiation and radioactive elements is becoming increasingly popular with the rapid developments in nuclear technology, radiotherapy, and radio diagnostic methods. However, ionizing radiation can directly or indirectly cause life-threatening complications such as cancer, radiation burns, and impaired immunity. Environmental contamination with radioactive elements and the depletion of ozone layer also contribute to the increased levels of radiation exposure. Radioprotective natural products have particularly received attention for their potential usefulness in counteracting radiation-induced damage because of their reduced toxicity compared with most drugs currently in use. Moreover, radioprotective substances are used as ingredients in cosmetic formulations in order to provide protection against ultraviolet radiation. Over the past few decades, the exploration of marine algae has revealed the presence of radioprotective phytochemicals, such as phlorotannins, polysaccharides, carotenoids and other compounds. With their promising radioprotective effects, marine algae could be a future source for discovering potential radioprotective substances for development as useful in therapeutics.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.29-34
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• 2014

Nanogels are internally cross-linked particles of sub-micrometer size made of hydrophilic polymers and are considered a distinct type of macromolecules, compared with linear and branched polymers or macroscopic gels. In this study, we studied a method of radiation induced synthesis of nanogels, which allows us to obtain tailored intra-molecularly crosslinked macromolecules of independently chosen molecular weight and dimensions. Thus, we report the possibility of applying the prepared nanogels using poly(acrylic acid) through electron beam irradiation for potential application as biomaterials. The nanogels were characterized by scanning electron microscopy (SEM). In addition, the size and zeta-potential of nanogels were measured by a particle size analyzer (PSA). The nanogels were prepared at an approximate size of 180 nm at 100 kGy and were spherical in shapes. The size of the nanogels decreased with increasing irradiation doses, and the absolute value of zeta potential increased with increasing irradiation doses.

• International Journal of Contents
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• v.16 no.2
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• pp.102-108
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• 2020

The purpose of this study was to estimate and analyze the potential radiation dose that the future visitors and the cleaning staff will be exposed to when the KRR-1 reactor is converted into a memorial hall. The radiation doses were estimated using the RESRAD-BUILD software, where case, building, receptor, shielding, and source parameters were applied as the input data. Also, the basic data for the assessment of the radiation doses were determined in an indirect manner using the data on the waste generated during the decommissioning process of the reactor. The assessment results indicate that the potential radiation dose to the visitors and the cleaning staff will be less than 1 mSv, the annual dose limit for the general public. However, if anyone for a significant period of time is close to the reactor, the overall dose will increase. The radiation dose for the future visitors and the cleaning staff was determined to be lower than the annual dose limit for the general public. Given such a risk, systematic measures, such as periodic monitoring or limiting hours, are imperative.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6251-6255
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• 2012

Radiation proctitis and radiation cystitis are major complications for patients with cervical carcinoma following radiotherapy. In the present study, we aimed to determine the potential risk factors for the development of radiation proctitis and radiation cystitis after irradiation. A total of 1,518 patients with cervical carcinoma received external beam radiotherapy (EBRT) followed by high-dose-rate intracavitary brachytherapy (HDRICB) in our hospital. The incidences of radiation proctitis and radiation cystitis were recorded and associations with different factors (age, time period, tumor stage) were analyzed with ${\chi}^2$ (chi-squared) and Fisher exact tests. We found that 161 and 94 patients with cervical carcinoma were diagnosed with radiation proctitis and radiation cystitis, respectively, following radiotherapy. The prevalence of Grade I-II radiation proctitis or radiation cystitis was significantly lower than that of Grade III (radiation proctitis: 3.82% vs. 6.76%, P < 0.05; radiation cystitis: 2.31% vs. 3.87%, P < 0.05) and was significantly enhanced in patients with late stage (IIIb) tumor progression compared to those in early stage (Ib, IIa) (P < 0.05). Moreover, the incidence of radiation proctitis and cystitis was not correlated with age or, time period following radiation, for each patient (P > 0.05). These observations indicate that a late stage of tumor progression is a potential risk factor for the incidence of radiation proctitis and cystitis in cervical carcinoma patients receiving radiotherapy.

• The Journal of the Korean dental association
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• v.52 no.3
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• pp.147-152
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• 2014

Recently the patient exposure by medical and dental x-ray examination has grown rapidly and diagnostic radiology represents the largest source of man-made radiation. For the patient protection, the principle of justification and optimization should be followed. All the radiographic examinations have to show a potential benefit to the patient weighing against the potential risk. After they are justified, the radiographic exposure should be kept as low as reasonably achievable, taking into account economic and social factors. For the safe use of radiation in dentistry, the radiation safety management in accordance with the legislation is important. The present status and the future of radiation safety management in dental radiology in Korea and other country will be discussed.

• Journal of Radiation Protection and Research
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• v.42 no.4
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• pp.205-211
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• 2017

Background: Radiation is used in a variety of areas, but it also poses potential risks. Although radiation is often used with great effectiveness in many applications, people perceive potential risks associated with radiation and feel anxious about the possibility of radiation exposure. Various methods of measuring radiation doses have been developed, but there is no way for the general public to measure their doses with ease. Currently, many people use smartphones, which provide information about the location of an individual phone through network connections. If a smartphone application could be developed for measuring radiation dosage, it would be a very effective way to measure individuals' radiation doses. Thus, we conducted a survey study to assess the social acceptance of such a technology by the general public and their intent to use that technology to measure radiation doses, as well as to investigate whether such an intention is correlated with anxiety and attitudes toward the use of radiation. Materials and Methods: A nationwide online survey was conducted among 355 Koreans who were 20 years old or older. Results and Discussion: Significant differences were found between the genders in attitudes, perceptions of radiation risk, and fears of exposure to radiation. However, a significant difference according to age was observed only in the intent to use a smartphone dose measurement application. Attitudes towards the use of radiation exerted a negative effect on radiation risk perception and exposure anxiety, whereas attitudes towards the use of radiation, risk perception, and anxiety about exposure were found to have a positive impact on the intent to use a smartphone application for dose measurements. Conclusion: A survey-based study was conducted to investigate how the general public perceives radiation and to examine the acceptability of a smartphone application as a personal dose monitoring device. If such an application is developed, it could be used not only to monitor an individual's dose, but also to contribute to radiation safety information infrastructure by mapping radiation in different areas, which could be utilized as a useful basis for radiation research.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.31.1-31.5
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• 2015

Background: Pathologic fractures are caused by diseases that lead to weakness of the bone structure. This process sometimes occurs owing to bony change after radiation therapy. Treatment of pathologic fractures may be difficult because of previous radiation therapy. Methods: In this study, we analyzed clinical and radiographic data and progress of five patients with mandibular pathological fractures who had received postoperative radiation therapy following cancer surgery. Result: Patients received an average radiation dose of 59.2 (SD, 7.2) Gy. Four of five patients exhibited bone union regardless of whether open reduction and internal fixation (OR/IF) was performed. Patients have the potential to heal after postoperative radiation therapy. Treatment of a pathologic fracture following postoperative radiation therapy, such as traditional treatment for other types of fractures, may be performed using OR/IF or CR. OR/IF may be selected in cases of significant bone deviation, small remaining bone volume, or occlusive change. Conclusion: Patients have the potential to heal after postoperative radiation therapy.

• Journal of Astronomy and Space Sciences
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• v.32 no.1
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• pp.39-44
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• 2015

It is well known that the space radiation dose over the polar route should be carefully considered especially when the space weather shows sudden disturbances such as CME and flares. The National Meteorological Satellite Center (NMSC) and Korea Astronomy and Space Science Institute (KASI) recently established a basis for a space radiation service for the public by developing a space radiation prediction model and heliocentric potential (HCP) prediction model. The HCP value is used as a critical input value of the CARI-6 and CARI-6M programs, which estimate the aviation route dose. The CARI-6/6M is the most widely used and confidential program that is officially provided by the U.S. Federal Aviation Administration (FAA). The HCP value is given one month late in the FAA official webpage, making it difficult to obtain real-time information on the aviation route dose. In order to overcome this limitation regarding time delay, we developed a HCP prediction model based on the sunspot number variation. In this paper, we focus on the purpose and process of our HCP prediction model development. Finally, we find the highest correlation coefficient of 0.9 between the monthly sunspot number and the HCP value with an eight month time shift.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2006.11a
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• pp.319-320
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• 2006

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.820-823
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• 2007

In the wavenumber domain, each point on a radiation sphere indicates a plane wave of the frequency corresponding to radius of the sphere and the position on the sphere shows propagating direction of the plane wave. This concept is extended from the research by Choi[1] where he focus acoustic potential energy at a point on a radiation sphere. Here we propose the method to focus the energy at a point on the radiation sphere, as a result, we can easily generate a plane wave which propagates to any direction that we want.