• Plant Journal
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• v.14 no.1
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• pp.42-46
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• 2018

The flow and heat transfer characteristics inside a solar chimney power plant system are analyzed in this article. 3-D model with the $k-{\varepsilon}$ turbulence closure was developed. In this model, to solve the radiative transfer equation the discrete ordinates radiation model was implemented, using a two-band radiation model. To simulate radiation effects from the sun's rays, the solar ray tracing algorithm was coupled to the calculation via a source term in the energy equation. Simulations were carried out for a system with the geometry parameters of the Manzanares power plant. Based on the numerical results, the velocity and temperature distributions were illustrated and the results were validated by comparing with experimental data of the Manzanares prototype power plant. Moreover, temperature profile of the ground surface of the system was illustrated.

• Elastomers and Composites
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• v.55 no.3
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• pp.222-228
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• 2020

Rubber materials, used in nuclear power plants, need high heat-oxidation resistance to curing or cracking under a heat aging environment. This is because they are applied to environments with high temperature, high humidity, and radiation exposure. Nuclear radiation causes additional hardening or degradation, therefore, rubber materials need radiation resistance that satisfies the general and any accidental conditions produced in the power plant. Therefore, in this study, we developed a rubber material with excellent heat and radiation resistance for the diaphragm seal of a nuclear steam generator nozzle dam. The rubber material greatly improved the reliability of the steam generator nozzle dam. In addition, 30 inch and 42 inch diaphragm seals were manufactured using the developed rubber material. A nozzle dam was installed in a nuclear power plant and tested under the same conditions as a steam generator to evaluate safety and reliability. In the future, the performance and safety of diaphragm seals developed through field tests of nuclear power plants will be evaluated and applied to currently operating and new nuclear power plants.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.15-29
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• 2016

Research background: Despite the visible growth in radiation usage and nuclear power development, the analysis of their relationship with fundamental rights, a subject of public concern regarding issues including the right to health, environmental rights, safety rights, the right to know, the right to development, and the right to life, is currently non-existent. Methods: By examining various fundamental rights in the context of positive laws regarding radiation and nuclear power in an idealistic perspective that guarantees the maximum degree of rights, this paper aims to propose legislative supplements that will lead to improvements in quality of life. Result and discussion: In the South Korean Constitution, radiation and nuclear power is a subject incorporating several rights, including at least 12 clauses that are directly related to fundamental rights; these constitutional rights are manifested in the various clauses of the 14 positive laws regarding radiation and nuclear power. The question on the relative importance of each fundamental right as reflected in these positive laws- whether the right to life should be prioritized or considered equal in weight to the right to health, environmental rights, the right to know, and safety rights- requires careful deliberation and is difficult to humanly resolve in the short term. Conclusion: Making policy that expands the usage of radiation and nuclear power while simultaneously preventing their associated risks is an important task for the Republic of Korea, and a proper value judgment is necessary to find a balance in its associated rights.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1145-1154
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• 2018

In order to prevent interference and interference of the frequency, it is required to convert the regulatory standard into the center of the radiation power radiated to the actual public. Since the radiation power regulation is related to general radio management such as technical standards, permits, and inspections, it is gradually introduced in consideration of applicability and urgency, and the radiation power related laws of major countries And a method of controlling the output of the radio equipment such as measurement, inspection, and authentication. In Korea, the proportion of antenna power supply is high, and in Europe, radiation power is high. Since the number of radio stations will increase and diversify in the future, institutional improvement should be made so that it can be measured in parallel with the radiocommunication infrastructure of the space manager. In order to convert to the radiative power management system, the system for the related radio system needs(Technical standards, certification, inspection of radio stations, post-management, etc.) to be improved.

• Journal of Radiation Protection and Research
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• v.23 no.3
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• pp.197-210
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• 1998

Regulations for the safe transport of radioactive material published by IAEA Safety Standard Series ST-l is reviewed and summarized. Safety Series No.115(International standard of radiation protection and safety for ionizing radiation and radiation sources), which reflected the new recommendation of ICRP60 published in 1991, has been a important encouragement for IAEA to revise their safety series related to the transportation of radioactive materials. IAEA Safety, Standard Series No. ST-l is summarized by comparing IAEA Safety Series No.6 regarding radiation protection system and its implementation, technical standards of packages, concept of Q system and exemption of regulation. The IAEA regulations of transportation of radioactive materials is summarized from the viewpoint of radiation protection and safety assessment. Research on transportation system of radioactive waste is suggested as a further study.

• The Journal of the Acoustical Society of Korea
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• v.42 no.1
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• pp.1-6
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• 2023

Sound radiated from a structure in vibration is an important physical characteristic to evaluate vibro-acoustic problem. Although sound radiation power can be typically obtained by intensity measurement, long measuring time and strict measuring condition remain difficult. As an alternative method, simulation-based estimation can be taken into account and its accuracy is known to be acceptable. However, difficulty still lies in that specialized softwares may be necessary to obtain sound radiation power and radiation efficiency. In this context, this study suggests two methods using an ordinary FE method to calculate sound radiation power. They are well-known reciprocity technique and p-p method, which are basically test methods. It is shown that either method can practically estimate sound radiation in the frame of conventional Finite Element Method (FEM). The methods and their corresponding limit are discussed with some results.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.6
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• pp.745-752
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• 2018

ICs(Integrated circuits) for nuclear power plant exposed to radiation environment occur malfunctions and data errors by the TID(Total ionizing dose) effects among radiation-damage phenomenons. In order to protect ICs from the TID effects, this paper proposes a radiation-hardening of the logic circuit(D-latch) which used for the data synchronization and the clock division in the ICs design. The radiation-hardening technology in the logic device(NAND) that constitutes the proposed RH(Radiation-hardened) D-latch is structurally more advantageous than the conventional technologies in that it keeps the device characteristics of the commercial process. Because of this, the unit cell based design of the RH logic device is possible, which makes it easier to design RH ICs, including digital logic circuits, and reduce the time and cost required in RH circuit design. In this paper, we design and modeling the structure of RH D-latch based on commercial $0.35{\mu}m$ CMOS process using Silvaco's TCAD 3D tool. As a result of verifying the radiation characteristics by applying the radiation-damage M&S (Modeling&Simulation) technique, we have confirmed the radiation-damage of the standard D-latch and the RH performance of the proposed D-latch by the TID effects.

• Journal of Radiation Protection and Research
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• v.48 no.3
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• pp.153-161
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• 2023

Background: Fukushima Medical University (FMU) is located 57 km northwest of the Fukushima Daiichi Nuclear Power Plant. Our laboratory has been conducting environmental radiation measurements continuously before and after the nuclear accident. We aimed to report the observed behavior of radiation originating from the released radioactive materials due to the accident, predict future trends, and disseminate the results to the local residents. Materials and Methods: Measurements of the counting rate by a diameter of 76 mm and a length of 76 mm thallium-doped sodium iodide (NaI[Tl]) scintillation detector (S-1211-T; Teledyne Brown Engineering Environmental Services) in the central part of the laboratory, and the dose rate outward at the window by NaI(Tl) scintillation detector and digital processor (EMF211; EMF Japan Co. Ltd.) were conducted. Results and Discussion: Measurements by Teledyne S-1211-T showed that in the early stages, radiation from radioactive isotopes with short half-lives was dominant, while radiation from radioactive isotopes with longer half-lives became dominant as the measurement period became longer. Through nonlinear least squares regression, both short and long half-lives were successfully determined. It was also possible to predict how the radiation dose would decrease. The environmental radiation trends around FMU were measured by the EMF211. Both measurements were affected by rainfall and snow accumulation. Decontamination work on the FMU campus impacted measurements by the EMF211 especially. Conclusion: The results of two types of measurements, one at the center and the other at the window side of the laboratory, were presented. By applying a simplified model, radiation from radioactive isotopes with short and long half-lives was identified. Based on these results, future trends were predicted, and the information was used for public communication with the local residents.

• Journal of the Korean Society of Radiology
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• v.11 no.6
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• pp.483-491
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• 2017

This study investigates the perception of the general public through analysis of various potential risk factors reflecting nuclear power generation and nuclear power (radiation) and risks. A total of 293 copies of the data were collected from various strata in Busan. As a result, among the potential factors in everyday life, there was a high awareness of the risk to the fire. Next, the perception of risk for radiation terror and nuclear (nuclear) energy was relatively high compared to other risk factors. In the analysis according to age, educational background, and political ideological tendency, the results were contradictory to the necessity, risk and safety of nuclear power generation. The potential risk factors and the perception of nuclear power according to the tendency of political ideology were analyzed to be positive recognition of conservative ideology and negative recognition of progressive group. In other words, the perception of nuclear power was analyzed differently according to the tendency of political ideology. Therefore, it should be decided to reflect the opinions of experts and various opinions of the general public in the setting of nuclear radiation (radiation), it is believed that ordinary people need to take flexible action without having a vague sense of anxiety about various potential risks and nuclear power (radiation) based on objective and scientific grounds.

• Journal of Nutrition and Health
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• v.46 no.2
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• pp.156-165
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• 2013

This study examined how achievement of session goals contributes to outcomes of subjects after participation in a 12-week lifestyle intervention program in men with metabolic syndrome (MetS). Thirty office workers with MetS, aged $47.2{\pm}6.6$ years, participated in this study, from March to July, 2011. The intervention program included face-to-face counseling five times during the 12-week period. Counselors and subjects designed session goals for each round. The average of the goal achievement rate was calculated based on compliance for each round. The subjects were divided into three groups according to their tertiles of achievement rate: Low-compliance group (LC, < 59%), medium-compliance group (MC, 59-70%), and high-compliance group (HC, > 70%). Anthropometry, biochemical index, and nutrient intake were examined at baseline and at the end of the 12-week intervention program. After the intervention, diastolic blood pressure (DBP) showed a significant decrease in the LC group, and waist circumference (WC) showed a significant decrease in the MC group. Systolic blood pressure (SBP), DBP, and low-density lipoprotein cholesterol (LDL) showed a significant decrease in the HI group. Changes in SBP and DBP were significantly lower in the HC group than in the MC group (p < 0.05, p < 0.01). Changes in LDL were significantly lower in the HC group than in the MC group (p < 0.05). Results for intake of total energy, protein, fat, and sodium, as well as rates of carbohydrate and fat intake, showed a significant decrease in all participants (p < 0.05). The change in fiber was significantly higher in the HC group than in the MC group (p < 0.05). The change of fruit serving size showed a significant increase in the HC group (p < 0.01). The number of risk factors for MetS showed a significant decrease in the LC and HC groups (p < 0.05), however, no significant mean differences were observed among the three groups. In conclusion, participation in this intervention program resulted in positive effects on risk factors for MetS, nutrient intake, and dietary habits, especially in the High-compliance group.