• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.27-35
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• 2015

Objectives: To investigate safety and health management, conditions in factories or facilities handling radiation-generating devices and radioactive isotopes were reviewed in terms of regulations of radiation safety control in Korea. Radiation exposure levels generated at those facilities were directly measured and evaluated for establishing an effective safety and health management plan. Methods: Government organizations with laws and systems of radiation safety and health were investigated and compared. There are three laws governing radiation-related employment such as occupational safety and health acts, nuclear safety acts, and medical service acts. We inspected 12 workplaces as research objects:four workplaces that manufacture and assemble semiconductor devices, three non-destructive inspection workplaces that perform inspections on radiation penetration, and five workplaces in textile and tire manufacturing. Monitoring of radiation exposure was performed through two methods. Spatial and surface monitoring using real-time radiation instruments was performed on each site handling radiation generating devices and radioactive isotopes in order to identify radiation leakage. Results: According to the occupational safety and health act, there is no legal obligation to measure ionizing radiation and set dose limits. This can cause confusion in the application of the laws, because the scopes and contents are different from each other. Surface dose rates in radiation generating devices such as implanters, thickness gages and accelerators, which were registered according to nuclear safety acts, using surveymeters, and seven of 36 facilities(19.4%) exceeded the international standards for surface radiation dose of $10{\mu}Sv/hr$. Conclusions: The results showed that occupational health and safety acts require a separate provision for measuring and assessing the radiation exposure of workers performing radiation work. Like noise, ionizing radiation will also periodically be controlled by including it in the object factors of work-environment measurement.

• Progress in Medical Physics
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• v.33 no.3
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• pp.25-35
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• 2022

Purpose: Planning for radiotherapy relies on implicit estimation of the probability of tumor control and the probability of complications in adjacent normal tissues for a given dose distribution. Methods: The aim of this pilot study was to reconstruct dose-volume histograms (DVHs) from text files generated by the Eclipse treatment planning system developed by Varian Medical Systems and to verify the integrity and accuracy of the dose statistics. Results: We further compared dose statistics for intensity-modulated radiotherapy of the head and neck between the Eclipse software and software developed in-house. The dose statistics data obtained from the Python software were consistent, with deviations from the Eclipse treatment planning system found to be within acceptable limits. Conclusions: The in-house software was able to provide indices of hotness and coldness for treatment planning and store statistical data generated by the software in Oracle databases. We believe the findings of this pilot study may lead to more accurate evaluations in planning for radiotherapy.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.717-724
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• 2023

An essential step in evaluating and comparing the performance of two passive radiation dosimeter types, thermosluminescent (TLD) and optically stimulated luminescence (OSL), used by workers in environments with ionizing radiation for individual radiological monitoring and control of external exposure at various times (cumulative dose for 1 month), is to compare the measured dose accuracy, energy response, and coefficient of variation. In fact this performance study consists in determining the accuracy of both R(10) and R(0.07) which are considered as the ratios of the measured dose (Hp(10) or Hp(0.07)) to the delivered dose (Hp(10) or Hp(0.07)) for each photon energy. The validity of the results of this test is based on the acceptance limits of the ICRP and the international standard IEC-62387. The relative energy response used is normalized to the ¹³⁷Cs 662 keV energy to find which energy response is closest to the ideal case, and the coefficient of variation that allows to determine the statistical fluctuation of the Hp(10) and Hp(0.07) doses. The results of the accuracy test for the OSL and TLD dosimeters are acceptable because they fall within the ICRP limits. For the energy response, the OSL performs better than the TLD for Hp(10) and Hp(0.07), and for the coefficient of variation, the OSL satisfies the requirements of ISO 62387 for both Hp(10) and Hp(0.07), while the TLD satisfies these requirements only for the measurement of Hp (0.07).

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.3
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• pp.42-52
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• 2015

Since the tax-free system for overseas laborers was implemented in 1974, the tax-free limits of international air crew, overseas construction workers and crewmen of deep-sea fishing ships and ocean-going ships had been identical by 2005, but there are big differences, currently. The Ministry of Strategy and Finance pointed out the poor working environments and international competitiveness of the industries to explain the reason for the differential tax-free limit. From this perspective, the fairness of the tax-free system for overseas laborers was analyzed. This is an empirical study, based on the objective fact. The study finding showed that international air crew were working in the structural flight work environments to threaten the right of health due to jet lag and excessive exposure to high-altitude cosmic radiation. Therefore, it was analyzed there should be a proper system reform to apply the tax-free limits to international air crew which are identical to those applied to overseas construction workers and crewmen of deep-sea fishing ships and ocean-going ships, for a fair taxation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.8 no.2
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• pp.23-27
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• 2002

Reballasting at sea, as recommended by the IMO guidelines, currently provides the best-available measure to reduce the risk of transfer of harmful aquatic organisms, but is subject to serious ship-safety limits. It is therefore extremely important that alternative, effective ballast water management and treatment methods are developed as soon as possible, to replace reballasting at sea. Filtration-Ultraviolet radiation-Electrolytic process (FUE) was evaluated for disinfection of seawater used In ballast water Optimal current density and UV light intensity were 2.0A/dm$^2$ and, 220㎼/$\textrm{cm}^2$/m with which 100% reduction time was 2sec in a Ultraviolet radiation-Electrolytic process. This study showed that FUE process was effective for the disinfection of commonly isolated bacteria and bacillus from ballast water.

• Advanced Industrial SCIence
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• v.2 no.3
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• pp.1-7
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• 2023

Recently, it is increasing that a issue of concern about radiation exposure. It affects soil, water, air, crops, etc., and in the long term, environmental pollution and food pollution occur, and it is considered to cause social problems and economic damage. Radiation exposure causes diseases and health problems, but as a method for diagnosing diseases, nuclear medicine tests such as X-ray imaging, CT, and PET-CT are conducted, and radiation isotopes are exposed for the purpose of cancer treatment. A Hungarian case study on radiation in water, particularly drinking water, following the release of radioactive waste from Fukushima, and an examination of the Larsemann Hills area in Antarctica, found that it was within the prescribed radioactivity limits of drinking water recommended by the World Health Organization. We looked at radioprotective agents, focusing on DNA damage, cell and organ damage, and cancer, and also investigated various literatures on ACE inhibitors, antioxidants, and natural substances among restoration materials. Although exposed to radiation in everyday life, the reason why it can be safe is probably because there is a radiation protection material and a recovery material for radiation exposure, so we are trying to find possible materials.

• Journal of Radiation Protection and Research
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• v.28 no.3
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• pp.173-182
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• 2003

A prototype liquid scillatillator system for measurement of multiple beta-labeled mixtures was developed and its characteristic was investigated. The signal processing system consists of two photomultiplier tubes and the coincident count circuit. The characteristic of the system was analyzed using 4 beta-labeled samples $(^3H,\;^{14}C,\;^{36}Cl\;and\;^{90}Sr)$. Beta spectra from the samples were obtained without radiation shielding, and the detection limits for each nuclides were estimated based on the spectra. The estimated detection limits were compared to the legal regulation values. It is found that the liquid radioactive nuclides are detectable well below the legal regulation values.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.351-355
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• 1998

Cutaneous angiosarcomas are uncommon malignancies which account about 1$\%$ of sarcomas. They are found most commonly in the head and neck regions, frequently on the scalp. Although preferred treatment has been combined surgery and postoperative radiation therapy, the extensiveness and multiplicity of the lesions set limits to such an approach and the patient is often referred for radiotherapy without surgery. As the entire scalp usually needs to be treated, radiation therapy is a challenging problem to radiation oncology staffs. We report a case of angiosarcoma of the scalp, which was treated successfully by radiation therapy with a simple and repeatable method using mixed Photon and electron beam technique. Using a bolus to increase the surface dose of the scalp and to minimize dose to the normal tissues of the brain desirable but difficult technically to be well conformed to the three dimensional curved surface such as vertex of the head. A helmet made of thermoplastics filled with paraffin was elaborated and used for the treatment, resulting of the relatively uniform surface doses along the several points measured on the scalp, the difference among the points not exceeding 7$\%$ of the prescribed dose by TLD readings.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.12
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• pp.1401-1411
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• 2010

In this paper, we suggested the tolerance limits of FAR(Fully Anechoic Room) using correlation factor between OATS(Open area Test Site) to measure EMI(Electromagnetic Interference) and FAR to measure EMS(Electromagnetic Susceptibility). FAR Project(SMT4-CT96-2133), CISPR/A/665/DTR, and CISPR A/665/DTR documents are analyzed and theoretical correlation factor based on the documents and theoretical equations is drawn. To obtain the experimental correlation factor, EUT(Equipment Under Test) is fabricated as well as measured at the 10 m distance OATS and in the 3 m distance FAR. Also, to suggest the tolerance limits of EUT with multi sources, radiation theory for electric and magnetic dipoles is programmed. We drew the correlation factor for EUT with multi sources through the programs. As the tolerance limits of FAR is newly defined, It can be used alternative test site for OATS to measure EMI, efficiently.

• Biomolecules & Therapeutics
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• v.25 no.2
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• pp.202-212
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• 2017

Doxorubicin (DOX) is a highly effective chemotherapeutic agent; however, the dose-dependent cardiotoxicity associated with DOX significantly limits its clinical application. In the present study, we investigated whether Rb1 could prevent DOX-induced apoptosis in H9C2 cells via aryl hydrocarbon receptor (AhR). H9C2 cells were treated with various concentrations ($-{\mu}M$) of Rb1. AhR, CYP1A protein and mRNA expression were quantified with Western blot and real-time PCR analyses. We also evaluated the expression levels of caspase-3 to assess the anti-apoptotic effects of Rb1. Our results showed that Rb1 attenuated DOX-induced cardiomyocytes injury and apoptosis and reduced caspase-3 and caspase-8, but not caspase-9 activity in DOX-treated H9C2 cells. Meanwhile, pre-treatment with Rb1 decreased the expression of caspase-3 and PARP in the protein levels, with no effects on cytochrome c, Bax, and Bcl-2 in DOX-stimulated cells. Rb1 markedly decreased the CYP1A1 and CYP1A2 expression induced by DOX. Furthermore, transfection with AhR siRNA or pre-treatment with AhR antagonist CH-223191 significantly inhibited the ability of Rb1 to decrease the induction of CYP1A, as well as caspase-3 protein levels following stimulation with DOX. In conclusion, these findings indicate that AhR plays an important role in the protection of Ginsenoside Rb1 against DOX-triggered apoptosis of H9C2 cells.