• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.133-141
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• 2020

A geological repository comprises a natural barrier and an engineered barrier system. Its design components consist of canisters, buffers, backfill, and near-field rock. Among the engineered barrier system components, bentonite buffers minimize the groundwater flow from near-field rock and prevent the release of nuclide. Investigation of the hydraulic conductivity of the buffer to groundwater flow is an important factor in the performance evaluation of the stability and integrity of the engineered barrier of the repository. In this study, saturated hydraulic conductivity tests were performed using Gyeongju bentonite at various dry densities and temperatures, and a hydraulic conductivity prediction model was developed through multiple regression analysis using the 120 result sets of hydraulic conductivity. The test results showed that the hydraulic conductivity tends to decrease as the dry density increases. In addition, the hydraulic conductivity increased with increasing temperature. The multiple regression analysis results showed that the coefficient of determination (R²) of the hydraulic conductivity prediction equation was as high as 0.93. The hydraulic conductivity prediction equation presented in this study could be used for the design of engineered barrier systems.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.35-43
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• 2016

Recently, the pipeline system for waste transportation has been increasingly constructed as new solution for the waste collection and disposal system by constantly increasing domestic waste which issued as social problem. The pipeline system is constructed through long distance, so proper long-term monitoring system is necessary which available to detect the damage location for the effective maintenance. In this paper, the experimental study is carried out to evaluate the applicability of optical strain gauge sensor based on FBG for the long-term monitoring system. Three test parameters such as pressure leaking, blockage and deformation are considered as typical damages for real-scale pipeline test specimen. In order to measure flexural and volumetric strain and temperature, three FBG sensors are installed at each monitoring sections. From the test results, this study suggested effective methods of sensor installation and arrangement. Also the sensor spacing for the design of monitoring system using FBG sensor is derived by the correlation of distances from deformation between sensor responses.

• Design Convergence Study
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• v.14 no.4
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• pp.119-132
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• 2015

The enforcement of volume-rate disposal system which has been resulted in reducing the household waste and increasing the amount of recycled contents is showing positive effects that are generating social and economic benefits, However due to the lack of user's perception about how to separate and dispose of recycling wastes, some problems are constantly raised, like food waste is disposed in the standard volume-rate garbage bag. By rearranging visual information printed on standard plastic garbage bags (SPGB), this study attempted to find ways to deliver the information regarding how to use them properly. In order to achieve this, from the perspective of visual information design, the study examined the cases of visual information printed on nine SPGB from domestic and overseas. Among these, this study conducted a survey on user's awareness of visual information printed on SPGB in three districts of Seoul, Korea. As a result, user-preferred items were identified. Based on the result, this study selected information to be printed on SPGB, established the hierarchical order of the selected information, and proposed a guideline for using SPGB with informative graphics; therefore, the effectiveness of information delivery was improved. In addition, this study also examined the external validity of the guideline by comparing a survey on user's awareness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.151-159
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• 2020

This study examined the environment and landscape aspects of rural villages, which are based on agriculture, to regenerate a disappearing rural village. The lifestyle and living conditions in this area were examined and the field survey of this area was carried out. The main negative factors at the rural landscape and living environment, such as rural households garbage, compost piles, and farming wastes, were found. An improvement plan of the landscape in this area was then determined. The disposal conditions according to the garbage types were analyzed through a survey with the residents directly. Through this survey, the current negative factors in landscape were checked and various improvement methods were assessed. Based on this, an institutional framework about landscape improvement of a village was developed, and a fundamental resource that can improve the environment of rural communities by this system is suggested.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.261-267
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• 2004

Inventories, projections, and characteristics of spent nuclear fuel(SNF) generated from domestic nuclear power plants were updated to support high-level waste disposal system design. The historical and projected inventory by the end 2055 is expected to be 20,500 and 14,800MTU for PWR and CANDU spent nuclear fuel, respectively The ratio of quantity for TEX>$17{\times}17$ SNF was shown to be 0.6 as of 2003. The amount of TEX>$17{\times}17$ SNF, however, will be less than that of TEX>$16{\times}16$ KSFA after 2012, while the quantity of TEX>$16{\times}16$ KSFA will reach to 70% of the total spent fuels in the 2055. Average turnup of SNF revealed ~36GWD/MTU and ~40GWD/MTU for the period of 1994-1999 and 2000-2003, respectively. It is expected that the average burnup of SNF will exceed 45GWD/MTU at the end of 2000's. Therefore, it seems reasonable to use the TEX>$17{\times}17$ 4.5w/o, 45GWD/MTU as the Reference SNF at present state. The TEX>$16{\times}16$ KSFA 4.5w/o, 55GWD/MTU, however, should be Reference SNF after ~2010.

• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.57-63
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• 2004

In general steel sheet piles are used in the containment system, which are vertical barrier systems for waste disposal and landfill purposes, and roads in excavation for temporary structure. This paper presents case study of the use of an interlocking sheet pile for water and containment. Cut-off Z-type sheet pile joints are investigated to determine their permeability from the field test. Four different joint sealing materials are used in field test. The results showed joint permeability is significant time-dependent and joint-dependent. These are explored and conclusions on permeability characteristics of different sealants are noted. A case study gives a design example as well as suggestion on permeability and water tightness can be implemented in using the sheet pile barrier in civil and environment works. From the test results, the effective sealing programs of sheet pile interlocks are suggested.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.1
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• pp.110-116
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• 2020

As the management plan for domestic spent nuclear fuel is delayed, the storage of the operating nuclear power plant is approaching saturation, and the Kori 1 Unit that has reached its end of operation life is preparing for the dismantling plan. The first stage of dismantling is the transfer of spent nuclear fuel stored in storage at plants. The spent fuel management process leads to temporary storage, interim storage, reprocessing and permanent disposal. In this paper, the technical issues to be considered when transporting spent fuel in this process are summarized. The spent fuels are treated as high-level radioactive waste and strictly managed according to international regulations. A series of integrity tests are performed to demonstrate that spent fuel can be safely stored for decades in a dry environment before being transferred to an intermediate storage facility. The safety of spent fuel transport container must be demonstrated under normal transport conditions and virtual accident conditions. IAEA international standards are commonly applied to the design of transport containers, licensing regulations and transport regulations worldwide. In addition, each country operates a physical protection system to reduce and respond to the threat of radioactive terrorism.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.88-94
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• 2009

Life cycle costing is one of the most effective approaches for the cost analysis of long-life products such as the railroad vehicle. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. Especially, life cycle costing in the railroad industry has been focused on the maintenance cost. In this paper, the standard, guide and maintenance information of railroad vehicle were investigated, and the unique corrective and preventive maintenance templates of railroad vehicle were proposed. Maintenance cost of an auxiliary power supply system of EMU was predicted by using the proposed templates. The results show that the preventive maintenance, PM, cost is much higher compare to corrective maintenance, CM, cost because of daily and monthly maintenance tasks which require lots of labor work. It is expected that these templates can help railroad operators make maintenance strategies with consideration of the cost parameter.

• Tunnel and Underground Space
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• v.21 no.3
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• pp.225-234
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• 2011

In this study, an in situ heater test for investigating the thermo-mechanical behavior related to heat flow was carried out. It was the first in situ heater test in Korea. For the test, an adequate design of heater, observation sensors, and data logging system was developed and installed with a consideration of the site condition and the test purposes. It was possible to observe that steep joints are overwhelmingly developed in the test area from a joint survey. The major rock and rock mass properties at the test site could be determined from the thermal and mechanical laboratory tests using the rock cores from the site. From the measured rock temperature distribution, it was possible to observe the influence of the rock joints and the heat flow through tunnel wall. When the heater temperature was maintained as $90^{\circ}C$, the rock temperature at 0.3 m from the heater hole was increased up to $40^{\circ}C$.

• Magazine of the Korean Society of Agricultural Engineers
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• v.33 no.3
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• pp.73-80
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• 1991

In Korea, small-scale reclaimed areas have been suffering from many problems because of the lack of comprehensive developing strategy although considerable investments have been inputed by the public sector since 1970's. For 3 reclaimed sites in Chonnam Province chosen as case study areas, the analysis, the third attempt of widely-spanned studies on areal conditions, concentrated on their living conditions. Its results were as follows : 1. Although rural residents have increased their concern on health and medical services, the public sector can only serve basic and emergent level of them, and therefore, the private sector, which is mostly placed in urban areas and costed much higher than public one, has the dominant share of those services. So, because those costs are a great expense to rural residents, their supplying system should be planned with special reference to lightening the economic burden of them. 2. By the development of locally fitted programs and innovative systems, the rural education should be qualitatively improved to deal successfully with its small scale. That will result in increasing the schooling rate to schools in rural communities, lightening the economic burden of rural residents on education services and finally activating them to contribute the betterment of rural education. 3. Servicing level of water supply, sewerage and garbage disposal in the reclaimed areas has been remaining at the lower order even in other rural areas. In the design of rural water supply, average daily consumption per capita should be changed according to the composition rate of fishing households and variety of the source of water supply. 4. Most of rural residents in the reclaimed areas want to establish the welfare facilites for the infant, youth, aged and public bath However in the long-term basis, the cooperative production and processing facilities should be considered for modernized efficient farming.