• Environmental and Resource Economics Review
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• v.28 no.2
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• pp.177-200
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• 2019

Energy demand forecast which serves as an essential input in energy policy is exposed to multiple factors of uncertainty such as GDP and weather forecast uncertainty. The Master Plan of Electricity Market in Korea which is biennially prepared is critically based on fluctuating energy demand forecast whereas its resulting proposal on electricity generation mix is substantially irreversible. The paper provides a real options model to evaluate energy transition policy by considering Knightian uncertainty as a measure to study multiple uncertainties with multiple set of probability distributions. Our finding is that the current energy transition policy under the master plan is not robust in terms of securing stable management of electricity demand and supply system.

• Journal of the Korean GEO-environmental Society
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• v.12 no.1
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• pp.27-33
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• 2011

In general, the shear strength of a clay specimen under the direct shear test and the triaxial compression test increases with an increase in the shear rate. This study investigates the effects of shear rate and silt content on the stress-strain behavior of remolded Gwangyang clay, by changing the shear rate and the silt content. Based on the results of the triaxial compression tests, the equi-strain line of remolded Gwangyang clay shows initially positive slope and then becomes flat at certain strain level. As the strain level where the equistrain becomes flat is different depending on the soil with different silt contents, this can be considered as the inherent property of soil.

• Resources Recycling
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• v.30 no.4
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• pp.64-74
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• 2021

The importance of uranium metal is growing day by day in light of its increasing global demand for fulfilling societal needs through atomic power programs. Considering the high demand for uranium, it is necessary to find innovative hydrometallurgical techniques to separate uranium from other associated elements, especially vanadium. This study deals with the separation of uranium(VI) and vanadium(V) from sulfuric acid solutions using commercial amine-based extractants diluted in kerosene. The concentrations of the sulfuric acid solutions ranged from 0.005 to 5.0 mol/L. The effect of extractant concentration ranging from 0.005 to 0.2 mol/L was studied. The temperature was maintained at 25℃ and the experiment was performed for 30 min at an aqueous: organic phase ratio of 1 (A:O = 1:1). The calculated separation factors (SFs) are presented and comparisons are made among all the experiments.

• Journal of Internet Computing and Services
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• v.23 no.3
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• pp.1-12
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• 2022

As the performance of Unmanned Aerial Vehicles (UAVs) are improving and the prices are lowering, it is expected that the use of UAVs will continuously grow in the future. It is important to always maintain control signal and video communication to operate remote UAVs stably, especially in military UAV operations, as unexpected jamming attacks can result in fatal UAV crashes. In this paper, to improve the network reliability and low latency when supporting UAV operations, the anti-jamming performance of Second generation Anti-jam Tactical UHF Radio for NATO (SATURN) networks is analyzed and enhanced by applying Forward Error Correction (FEC) and Minimum Shift Keying (MSK) modulation as well as Hamming code based multiple transmission techniques.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.17 no.1
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• pp.8-17
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• 2021

The seat leakage test is required after the maintenance work on the valve seat. Either the test has been performed outside of the plant after cutting the valve from the pipe system or the simplified test has been performed so far. It was unable to perform the test at the plant site because it is hard to make a steady pressure on the valve inlet when it is installed in the pipe. This research aims to perform the leakage test in the nuclear power plant while it is installed in the pipe system. The mock-up test is performed by pressurizing the leak-off pipe on the valve body. The result is compared with traditional test result by pressurizing the valve inlet. Furthermore the chamber mock-up tests are performed under various conditions. The leak rate by the developed test using the leak-off pipe is found to be similar but greater than the leak rate by the existing test method. It implies that the test using the leak-off pipe is more conservative than the existing test. The methodology and the equipment which this paper suggests that on-site seat test is possible and the application of the technology could reduce the time and cost for the valve maintenance work significantly.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.459-464
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• 2023

Due to the development of advanced technology, a lot of digital radiographic equipment has been developed, which is very helpful for accurate diagnosis and treatment, and it is very important to train personnel who have acquired professional knowledge in order to use it safely and effectively. Students are exposed to the risk of radiation exposure in radiography training using diagnostic X-ray equipment, and some educational institutions do not use X-ray equipment due to management difficulties in accordance with the Nuclear Safety Act. As a solution to this, this study developed a medical radiation simulator for education that does not generate radiation by using a vision sensor and self-developed software. Through this, educational institutions can reduce the burden of administrative implementation according to the law, and students can obtain a high level of educational effects in a healthy practice environment without radiation exposure.

• Journal of Advanced Technology Convergence
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• v.3 no.2
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• pp.9-15
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• 2024

Due to the high inflation rate of dining out, along with changes in group meals or cafeteria services, office workers are increasingly using workplace cafeterias to reduce their meal expenses even slightly. With the recent development of ICT technology, various fields are realizing that not only are smartphones becoming more popular, but they are also becoming an integration of the latest technologies. In this paper, we analyze the current status of cafeterias with a large number of customers and propose ways to improve problems or difficulties. Since most people always carry their smartphones for urgent communication or work tasks, we aim to develop a cafeteria management system that utilizes the NFC function of smartphones. By presenting the process from customer entry to menu selection, it will enable more efficient use of the cafeteria.

• The Korean Journal of Air & Space Law and Policy
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• v.22 no.1
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• pp.29-54
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• 2007

Nuclear Power Sources(NPS) have been used since 1961 for the purpose of generating energy for space objects and have since then been recognized as particularly suited essential to some space operations. In January 1978 a malfuctioning Soviet nuclear powered satellite, Cosmos 954, re-entered the earth's atmosphere and disintegrated, scattering radioactive debris over a wide area of the Canadian Northwest Territory. This incident provided some reasons to international legal scholars to make some principles to regulate using NPS in outer space. In 1992 General Assembly adopted "Principles Relevant to the Use of Nuclear Power Sources in Outer Space". These NPS Principles set out certain legal and regulatory requirements on the use of nuclear and radioactive power sources for non-propulsive purposes. Although these principles, called 'soft laws', are not legal norms, they have much enfluences on state practices such as 1983 DBS Principles(Principles Governing the Use by States of Artificial Earth Satellites for International Direct Television Broadcasting), 1986 RS Principles(Principles Relating to Remote Sensing of the Earth from Space) and 1996 Declaration on International Cooperation in the Exploration and Use of Outer Space for the Benefit and in the Interests of all States, Taking into Particular Account the Needs of Developing Countries. As far as 1963 Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space is concerned the main points such as free use of outer space, non-appropriation of celestial bodies, application of international law to outer space etc. have become customary international law binding all states. NPS Principles might have similar characters according to states' willingness to respect them.

• The Korean Journal of Air & Space Law and Policy
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• no.spc
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• pp.35-58
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• 2007

Nuclear Power Sources(NPS) have been used since 1961 for the purpose of generating energy for space objects and have since then been recognized as particularly suited essential to some space operations. In January 1978 a malfuctioning Soviet nuclear powered satellite, Cosmos 954, re-entered the earth's atmosphere and disintegrated, scattering radioactive debris over a wide area of the Canadian Northwest Territory. This incident provided some reasons to international legal scholars to make some principles to regulate using NPS in outer space. In 1992 General Assembly adopted "Principles Relevant to the Use of Nuclear Power Sources in Outer Space". These NPS Principles set out certain legal and regulatory requirements on the use of nuclear and radioactive power sources for non-propulsive purposes. Although these principles, called 'soft laws', are not legal norms, they have much enfluences on state practices such as 1983 DBS Principles(Principles Governing the Use by States of Artificial Earth Satellites for International Direct Television Broadcasting), 1986 RS Principles(Principles Relating to Remote Sensing of the Earth from Space) and 1996 Declaration on International Cooperation in the Exploration and Use of Outer Space for the Benefit and in the Interests of all States, Taking into Particular Account the Needs of Developing Countries. As far as 1963 Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space is concerned the main points such as free use of outer space, non-appropriation of celestial bodies, application of international law to outer space etc. have become customary international law binding all states. NPS Principles might have similar characters according to states' willingness to respect them.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.3
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• pp.169-179
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• 2011

There are two types of nuclear reactors in Korea and they are PWR type and CANDU type. The safe management of the spent fuels from these reactors is very important factor to maintain the sustainable energy supply with nuclear power plant. In Korea, a reference disposal system for the spent fuels has been developed through a study on the direct disposal of the PWR and CANDU spent fuel. Recently, the research on the demonstration and the efficiency analyses of the disposal system has been performed to make the disposal system safer and more economic. PWR spent fuels which include a lot of reusable material can be considered being recycled and a study on the disposal of HLW from this recycling process is being performed. CANDU spent fuels are considered being disposed of directly in deep geological formation, since they have little reusable material. In this study, based on the Korean Reference spent fuel disposal System (KRS) which was to dispose of both PWR type and CANDU type, the more effective CANDU spent fuel disposal systems were developed. To do this, the disposal canister for CANDU spent fuels was modified to hold the storage basket for 60 bundles which is used in nuclear power plant. With these modified disposal canister concepts, the disposal concepts to meet the thermal requirement that the temperature of the buffer materials should not be over $100^{\circ}C$ were developed. These disposal concepts were reviewed and analyzed in terms of disposal effective factors which were thermal effectiveness, U-density, disposal area, excavation volume, material volume etc. and the most effective concept was proposed. The results of this study will be used in the development of various wastes disposal system together with the HLW wastes from the PWR spent fuel recycling process.