• Journal of Radiation Protection and Research
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• v.47 no.3
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• pp.143-151
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• 2022

Background: After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, biological alterations in the natural biota, including morphological changes of fir trees in forests surrounding the power plant, have been reported. Focusing on the terminal buds involved in the morphological formation of fir trees, this study developed a method for estimating the absorbed radiation dose rate using radionuclide distribution measurements from tree organs. Materials and Methods: A phantom composed of three-dimensional (3D) tree organs was constructed for the three upper whorls of the fir tree. A terminal bud was evaluated using Monte Carlo simulations for the absorbed dose rate of radionuclides in the tree organs of the whorls. Evaluation of the absorbed dose targeted ¹³¹I, ¹³⁴Cs, and ¹³⁷Cs, the main radionuclides subsequent to the FDNPP accident. The dose contribution from each tree organ was calculated separately using dose coefficients (DC), which express the ratio between the average activity concentration of a radionuclide in each tree organ and the dose rate at the terminal bud. Results and Discussion: The dose estimation indicated that the radionuclides in the terminal bud and bud scale contributed to the absorbed dose rate mainly by beta rays, whereas those in 1-year-old trunk/branches and leaves were contributed by gamma rays. However, the dose contribution from radionuclides in the lower trunk/branches and leaves was negligible. Conclusion: The fir tree model provides organ-specific DC values, which are satisfactory for the practical calculation of the absorbed dose rate of radiation from inside the tree. These calculations are based on the measurement of radionuclide concentrations in tree organs on the 1-year-old leader shoots of fir trees. With the addition of direct gamma ray measurements of the absorbed dose rate from the tree environment, the total absorbed dose rate was estimated in the terminal bud of fir trees in contaminated forests.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.67-70
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• 2009

First of all, this paper investigated scrupulously Occupational Safety and Healthy Agencies which take care of nucleus roles as accident protection organ of industrial circles in our country. Catching hold of elaborately lots of problems that each Agency holds, we tried to action to correct that faulty custom and invalidism. On the other hand, we exhort and encourage more available measures helping practically to protect industrial accident of work place receiving vicarious execution. Furthermore, both in name and reality, we try to be reborn as a mission institution of accidental prevention of medium and small work place. Therefore, the purpose of the present paper is to suggest substantial counterproposal for activation of Occupational Safety and Healthy Agency.

• Journal of the Korea Construction Safety Engineering Association
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• s.54
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• pp.29-35
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• 2011

First of all, this paper investigated scrupulously Occupational Safety and Healthy Agencies which take care of nucleus roles as accident protection organ of industrial circles in our country. Catching hold of elaborately lots of problems that each Agency holds, we tried to action to correct that faulty custom and invalidism. On the other hand, we exhort and encourage more available measures helping practically to protect industrial accident of work place receiving vicarious execution. Furthermore, both in name and reality, we try to be reborn as a mission institution of accidental prevention of medium and small work place. Therefore, the purpose of the present paper is to suggest substantial counterproposal for activation of Occupational Safety and Healthy Agency.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.249-253
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• 2001

Neutron dose assessment in criticality accidents using Whole Body Counter (WBC) was proved to be an effective method as rapid neutron dose estimation at the JCO criticality accident in Tokai-mura. The 1.36MeV gamma-ray of $^{24}Na$ in a body can be detected easily by a germanium detector. The Minimum Detectable Activity (MDA) of $^{24}Na$ is approximately 50Bq for 10miniute measurement by the germanium-type whole body counter at JNC Tokai Works. Neutron energy spectra at the typical shielding conditions in criticality accidents were calculated and the conversion factor, whole body activity-to-organ mass weighted neutron absorbed dose, corresponding to each condition were determined. The conversion factor for uncollied fission spectrum is 7.7 $[(Bq^{24}Na/g^{23}Na)/mGy]$.

• Journal of the Korea Safety Management & Science
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• v.12 no.4
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• pp.23-29
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• 2010

There are two kind of method to perform a safety management in industrial field. One is a management by safety manager employed in company and another one is safety management by acting agency. In case of the company that managed by the acting agency dose not coincide with the state of company and safety management performance because of the safety management is carry out by periodically. Therefore it is considered that the sufficient safety management is difficult. And a company that employ a safety manager also show a low level of safety management compare with the advanced country in view of safety and health. From the statistics of accident rate of the company, it is necessary that an improved safety management through the studying and analysing a coverall matters for the company that managed by acting company.

• Journal of the Korean Institute of Navigation
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• v.20 no.4
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• pp.45-58
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• 1996

$\ulcorner$Ministry Of Maritime Affairs And Fisheries$\lrcorner$was established on 8 August 1996 by emerging ex-$\ulcorner$Maritime and Port Administration$\lrcorner$, $\ulcorner$Fisheries Administration$\lrcorner$and some other marine-related organs such as $\ulcorner$Maritime Police Agency$\lrcorner$, $\ulcorner$Marine Accident Inquiry Agency$\lrcorner$, etc., for the purpose of enhancing development of national marine polices in various aspect and promoting marine safety and environmental protection activities. Therefore, the unification of marine casualty statistics is required for the need of appreciating present condition and problem. This paper shows the Client/Server computing system which could replace the existing Main Frame system set up by Maritime and Port Administration and Marine Accident Inquiry Agency. It also gives the way to connect every casualty related organ for data exchange of casualty information and INTERNET for opening casualty information to the public. So, applicable techniques and basic policy direction is dealt with.

• Journal of the Korean Society of Radiology
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• v.1 no.3
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• pp.23-34
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• 2007

To find how much radiation was exposed the patients who visit emergency room, a measurement study was made for radiation amount toward 200 patients selected randomly among visitors to an emergency room in a university hospital from March 16 to 31st, 2006. The results are as follows ; 1. Among the subjects 50 person(25.0%) were transferred from other hospitals, 24 persons(8.3) come after traffic accident, 50 persons for other accident and 76 persons for general medical care. 2. The average frequency of X-ray taking was calculated as 6.4 time per person among transferred patients, 14.5 times per person among patients with traffic accident and 2.6 times per person among general medical care. 3. The radiation exposure amount by kind of X-ray showed 28.9mGyfor general X-ray diagnosis, 84.2mGy for CT scanning and 1.02mGy for other special radiation study. 4. Average radiation exposure amount was calculated as 24.6mGy by transferred patients, 55.2mGy by patients with traffic accident, 17.1mGy by patients with other accidents and 17.0mGy by general patients. 5. Through the comparison of radiation exposure amount among to subject with maximum allowance threshold by International Commission on X-ray Radium Protection, transferred patients exceeded 6 times than allowance in whole body except extremities and joints, blood forming organ, reproductive system, vitreous body of eye, bone, thyroid gland, skin and etc, Patient suffered from traffic accidents were exposed 10 times more than allowance. In conclusion, the radiation exposure amount during X-rat diagnosis re too much and exceeded allowance standard by International Commission on X-ray Radium Protection. So further study and preventive measure to decrease radiation exposure by patients who visit emergency room.