• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.2
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• pp.103-111
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• 2014

In this study, the probabilistic internal pressure fragility analysis was performed by using the non-linear finite element analysis method. The target structure is one of the containment buildings of typical domestic pressurized water reactors(PWRs). The 3-dimensional finite element model of the containment building was developed with considering the large equipment hatches. To consider uncertainties in the material properties and structural capacities, we performed the sensitivity analysis of the ultimate pressure capacity with respect to the variation of four important uncertain parameters. The results of the sensitivity analysis were used to the selection of the probabilistic variables and the determination of their probabilistic parameters. To reflect the present condition of the tendon pre-stressing force, the data of the pre-stressing force acquired from the in-service inspections of tendon forces were used for the determination of the median value. Two failure modes(leak, rupture) were considered and their limit states were defined to assess the internal pressure fragility of target containment building. The internal pressure fragilities for each failure mode were evaluated in terms of median internal pressure capacity, high confidence low probability of failure(HCLPF) capacity, and fragility curves with respect to the confidence levels. The HCLPF capacity was 115.9 psig for leak failure mode, and 125.0 psig for rupture failure mode.

• Archives of design research
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• v.17 no.4
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• pp.233-240
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• 2004

Living in the modern age with well-developed scientific technologies, all of us are enjoying convenient lives because of 'energy'. Korea, poor in resources, is importing a large portion of its energy sources from abroad but energy consumption shows an upward tendency due to the continuing economic growth and the improvement of living conditions. The atomic energy is considered a self-reliant, alternative energy source like our country. However, it is necessary to educate the people on and publicize atomic power generation in the face of the widespread negative recognition that the atomic power plant is a hazardous facility. The study approaches to these matters with a human-friendly and environment-friendly coloring plan in the perspective of environment coloring plan. The study aims to minimize negative images of the atomic power, while highlighting its friendly and positive images so as to enhance the confidence of the people on the atomic power and to create a clean image for the atomic power. For this goal, the study examined and analyzed cases of Japanese nuclear power plants and domestic nuclear power plants, and also carried out an on-site survey in the sites in which nuclear power plants would be constructed to extract concrete colors through the analyses of their natural environment and actual conditions. The study also carried out a survey of residents in the regions to induce their participation, and reflected the survey results to the coloring plan. The study is expected to create a stable and friendly image of the nuclear power plant through materializing its environment-friendly image and remove negative recognition that the people have on the nuclear power plant. It also attempted an external environment-coloring plan a s a strategic means for positive publicity and through this, is expected to ultimately contribute to the creation of the new images of nuclear ower plants.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.235-243
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• 2016

In the near future, many countries, including the Republic of Korea, will face a significant increase in low level radioactive waste (LLW) from nuclear power plant decommissioning. The purpose of this paper is to look at blending as a method for enhancing disposal options for low-level radioactive waste from the decommissioning of nuclear reactors. The 2007 U.S. Nuclear Regulatory Commission strategic assessment of the status of the U.S. LLW program identified the need to move to a risk-informed and performance-based regulatory approach for managing LLW. The strategic assessment identified blending waste of varying radionuclide concentrations as a potential means of enhancing options for LLW disposal. The NRC's position is that concentration averaging or blending can be performed in a way that does not diminish the overall safety of LLW disposal. The revised regulatory requirements for blending LLW are presented in the revised NRC Branch Technical Position for Concentration Averaging and Encapsulation (CA BTP 2015). The changes to the CA BTP that are the most significant for NPP operation, maintenance and decommissioning are reviewed in this paper and a potential application is identified for decommissioning waste in Korea. By far the largest volume of LLW from NPPs will come from decommissioning rather than operation. The large volumes in decommissioning present an opportunity for significant gains in disposal efficiency from blending and concentration averaging. The application of concentration averaging waste from a reactor bio-shield is also presented.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.2
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• pp.295-310
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• 2014

DCS (Distributed Control System), the main control system of power plants, is an automated system for enhancing operational efficiency by monitoring, tuning and real-time operation. DCS is becoming more intelligent and open systems as Information technology are evolving. In addition, there are a large amount of investment to enable proactive facility management, maintenance and risk management through the predictive diagnostics. However, new upcoming weaponized malware, such as Stuxnet designed for disrupting industrial control system(ICS), become new threat to the main control system of the power plant. Even though these systems are not connected with any other outside network. The main control systems used in the power plant usually have been used for more than 10 years. Also, this system requires the extremely high availability (rapid recovery and low failure frequency). Therefore, installing updates including security patches is not easy. Even more, in some cases, installing security updates can break the warranty by the vendor's policy. If DCS is exposed a potential vulnerability, serious concerns are to be expected. In this paper, we conduct the penetration test by using NESSUS, a general-purpose vulnerability scanner under the simulated environment configured with the Ovation version 1.5. From this result, we suggest a log analysis method to detect the security infringement and react the incident effectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.276-284
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• 2019

Seismic research on bridges, dams and nuclear power plants, which are infrastructure in Korea, has been carried out since early on, but in the case of structures in thermal power plants, research is insufficient. In this study, a total of 192 dynamic analyzes were performed for 16 actual seismic waves and 12 PGAs. As a result, the probability of failure increased as the PGA value increased for each applied seismic wave, but it was different for each seismic wave. As a result, at 0.22G, the ratio of the compressive limit reached to the limit state was 25% and the ratio of the relative displacement reached the limit state was 13%. So, the probability of collapse due to compressive failure Is higher. Therefore, the fragility curve of the chimney which is the subject of this study can be used as a quantitative basis to determine the limit state of the target structure when an earthquake occurs and to be used for the safety design of the thermal power plants.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.127-136
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• 2022

This thesis is a study of "Ethics Seminar VII of Psychoanalysis" that Jacques Lacan (1901~1981) has the most attachment to.A translated version has not yet been released in Korea. The original French and English translations of Lacan Seminar VII were used for the study version. Lacan introduces an important concept in a seminar on the ethics of psychoanalysis. In German, it is 'das Ding'. It is translated as 'big thing' in Korean. Lacan introduces the term in French as 'La Chose'. In English, it is The Thing. "Big things" are also things that my mother gave me when I was young. It can also be interpreted as a loss of childhood that is not completely resolved. Therefore, Lacan' subject refers to develops a lifelong journey to recover the lost object. Lacan presents this point as the starting point of the psychoanalytic ethics. We try to re-examine the issue of ethics by tracing 'das Ding' as a lost place in the main article. First, We will look at the origins of das Ding. Second, through the relationship between love and das Ding, We will discuss who tries to fill Ding's void. Third, We will try to interpret the relationship between American ego psychology and das Ding in Lacan's scheme. Lastly, a posthumous subject will be dealt with through the play 'Mugunghwa has bloomed.'

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.4
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• pp.97-105
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• 2020

The genus Navicula, with its notably high species diversity, is one of the most important genera of the diatom assemblages of the tidal flats. In the present study, Navicula spartinetensis was firstly observed from Yellow Sea including both of Korean and Chinese tidal flats. Morphological description was also made based on the LM and SEM observation. Samples were collected from four locations in Korea, two in October 2006, one in July 2007, and one in July 2018, and seven location in China from June to July 2018. N. spartinetensis was firstly described by Sullvian & Reimer in 1975; Cells are lanceolate with narrow valve faces, 20-30 ㎛ long, 5-6 ㎛ wide, and the density of striae is 12-13 in 10 ㎛, and the terminal raphe ending curved in the same direction. N. spartinetensis has been previously reported from Europe and South America, and the present study has expanded its distribution to the Northeast Asia. In conclusion, the diversity of Korean marine benthic diatoms is still underestimated thus extensive further study of diatom taxonomy is needed.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.163-170
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• 2015

The interest of the people in the radioactive contamination of the water has increased significantly and the study about analysis and management of radioactive materials are being actively conducted. And monitoring spots have been expanded to the range of public water as well as drinking water by publishing the rule of drinking water quality standards and examination in the Environmental Enforcement Ordinance No. 553 of Korea. In this study, US EPA was investigated as the foreign advanced cases and the way that is appropriate for the Korea was sought by analyzing investigate radionuclide, interval and management. As a result, in the selection part of investigate radionuclide, geological survey, status of nuclear power plants and the presence of the use of artificial radionuclides of the Korea should be investigated and additionally after the selection of a few radionuclides, the systems should be extended to cover all possible radionuclides by considering radioactive pollution levels in humans may be exposed due to the annual drinking water. In the part of the investigate interval, the concept(MCL, DL) should be set up for preventing concentration detection of above MCL and it needs to the maintenance and management. For example, when the concentration is more than MCL, it should be investigated on a quarterly and when the concentration is lower than MCL, it should be investigated to each different interval and management. And the US EPA divided the management area and make the roadmap for managing drinking water. The each classified area has been organized to match the state budget and labor force and the individual data have been managed effectively by HPGe, the NaI, TLD and so on.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.343-356
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• 2016

The Korea Radioactive Waste Agency (KORAD) has developed a dual-purpose metal cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. The metal cask was designed in compliance with international and domestic technology standards, and safety was the most important consideration in developing the design. It was designed to maintain its integrity for 50 years in terms of major safety factors. The metal cask ensures the minimization of waste generated by maintenance activities during the storage period as well as the safe management of the waste. An activation evaluation of the main body, which includes internal and external components of metal casks whose design lifetime has expired, provides quantitative data on their radioactive inventory. The radioactive inventory of the main body and the components of the metal cask were calculated by applying the MCNP5 ORIGEN-2 evaluation system and by considering each component's chemical composition, neutron flux distribution, and reaction rate, as well as the duration of neutron irradiation during the storage period. The evaluation results revealed that 10 years after the end of the cask's design life, $^{60}Co$ had greater radioactivity than other nuclides among the metal materials. In the case of the neutron shield, nuclides that emit high-energy gamma rays such as $^{28}Al$ and $^{24}Na$ had greater radioactivity immediately after the design lifetime. However, their radioactivity level became negligible after six months due to their short half-life. The surface exposure dose rates of the canister and the main body of the metal cask from which the spent nuclear fuel had been removed with expiration of the design lifetime were determined to be at very low levels, and the radiation exposure doses to which radiation workers were subjected during the decommissioning process appeared to be at insignificant levels. The evaluations of this study strongly suggest that the nuclide inventory of a spent nuclear fuel metal cask can be utilized as basic data when decommissioning of a metal cask is planned, for example, for the development of a decommissioning plan, the determination of a decommissioning method, the estimation of radiation exposure to workers engaged in decommissioning operations, the management/reuse of radioactive wastes, etc.

• Korean Security Journal
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• no.41
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• pp.37-66
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• 2014

In recent years, with the development of computers and electronics, electronics and communication technology in a growing and each part is dependent on the cross-referencing makes all electronic equipment is obsolete due to direct or indirect damage EMP. Korea and the impending standoff North Korea has a considerable level of technologies related to the EMP, EMP weapons you already have or in a few years, the development of EMP weapons will complete. North Korea launched a long-range missile and conducted a nuclear test on several occasions immediately after, when I saw the high-altitude nuclear blackmail has been strengthening the outright offensive nuclear EMP attacks at any time and practical significance for the EMP will need offensive skills would improve. At this point you can predict the damage situation of Korea's security reality that satisfy the need, more than anything else to build a protective system of the EMP. The scale of the damage that unforeseen but significant military damage and socio-economic damage and fatalities when I looked into the situation which started out as a satellite communications systems and equipment to attack military and security systems and transportation, finance, national emergency system, such as the damage elsewhere. In General, there is no direct casualties reported, but EMP medical devices that rely on lethal damage to people who can show up. In addition, the State power system failure due to a power supply interruption would not have thought the damage would bring State highly dependent on domestic power generation of nuclear plants is a serious nuclear power plant accident in the event of a blackout phenomenon can lead to the plant's internal problems should see a forecast. First of all, a special expert Committee of the EMP, the demand for protective facilities and equipment and conduct an investigation, he takes fits into your budget is under strict criteria by configuring the contractors should be sifting through. He then created the Agency for verification of performance EMP protection after you have verified the performance of maintenance, maintenance, safety and security management, design and construction company organized and systematic process Guard facilities or secret communications equipment and perfect for the EMP, such as protective equipment maneuver system should take.