• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.10 no.3
• /
• pp.143-149
• /
• 2012

Groundwater flow simulations were performed to obtain data of groundwater flow used in a safety assessment for a hypothetical geological disposal facility assumed to be located in the KURT (KAERI Underground Research Tunnel) site. A regional scale modeling of the groundwater flow system was carried out to make boundary conditions for a local scale modeling. And, fracture zones identified at the study site were involved in the local scale groundwater flow model. From the results of the local scale modeling, a hydraulic head distribution was indicated and it was used in a particle tracking simulation for searching pathway of groundwater from the location of the hypothetical disposal facility to the surface where the groundwater reached. The flow distance and discharge rate of the groundwater in the KURT site were calculated. It was thought that the modeling methods used in this study was available to prepare the data of groundwater flow in a safety assessment for a geological disposal facility of radioactive wastes.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.16 no.3
• /
• pp.339-346
• /
• 2018

A geological repository system consists of a disposal canister with packed spent fuel, buffer material, backfill material, and intact rock. The buffer is indispensable to assure the disposal safety of high-level radioactive waste. Since the heat generated from spent nuclear fuel in a disposal canister is released to the surrounding buffer materials, the thermal properties of the buffer material are very important in determining the entire disposal safety. Especially, since thermal expansion can cause thermal stress to the intact rock mass in the near-field, it is very important to evaluate thermal expansion characteristics of bentonite buffer materials. Therefore, this paper presents a thermal expansion coefficient prediction model of the Gyeongju bentonite buffer materials which is a Ca-bentonite produced in South Korea. The linear thermal expansion coefficient was measured considering heating rate, dry density and temperature variation using dilatometer equipment. Thermal expansion coefficient values of the Gyeongju bentonite buffer materials were $4.0{\sim}6.0{\times}10^{-6}/^{\circ}C$. Based on the experimental results, a non-linear regression model to predict the thermal expansion coefficient was suggested and fitted according to the dry density.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.16 no.3
• /
• pp.29-37
• /
• 2008

The objective of this research is to evaluate the optimum treatment methods for disposal sludge cake at different temperatures and periods of time. The disposal dehydrated sewage cake used in this study was obtained from N wastewater treatment plant in the P City. This system consists of continuous conveyer thermal dryer and pyrolysis. The continual conveyer thermal dryer was operated to evaluate the optimum conditions with temperature settings, ranges from 130 to $180^{\circ}C$, loading rates of 650~750 kg/hr and operating times of 110~120 minutes. The continual pyrolysis was also operated to evaluate the optimum conditions with temperature settings, ranges from 650 to $750^{\circ}C$, loading rates of 100~158 kg/hr and operating times of 20~40 minutes. The sewage sludge cake has a moisture content of 78~80% (wt) which decreased up to 1~3%(wt) resulted in breaking of cell wall after operating the continuous conveyer thermal dryer and pyrolysis. Important parameters which were operating times, moisture contents, loading rates, conveyer velocities and rotary velocities effects on the thermal kinetics and dynamics were investigated to evaluate the optimum conditions for the continual thermal dryer and pyrolysis.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.10
• /
• pp.493-502
• /
• 2019

Recently, the installation of renewable energy including PV systems in distribution systems has increased energetically to cope with climate change and energy shortages according to the government's policy of renewable energy 3020. On the other hand, the electrical performance and lifespan of PV modules installed outdoors can be decreased considerably due to a range of deterioration phenomena depending on the ambient environmental factors. To overcome these problems, replacement of degraded PV modules with new ones is increased before the lifespan guaranteed by the makers of PV modules. Therefore, this paper proposes a disposal diagnosis algorithm to evaluate the time interval of the optimal replacement for PV modules according to performance degradation rate of PV modules. In addition, this study modeled an economic evaluation, which is composed of the cost and benefit of PV systems. From the simulation results based on the proposed modeling and algorithm to consider the performance degradation rate specifically, the replacement approach was found to have the best B/C ratio in 10th year with a 3[%] degradation rate and the disposal diagnosis algorithm of PV modules are useful and practical tools for economic evaluations of the replacement of PV modules.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.28 no.3
• /
• pp.201-210
• /
• 2022

Expanded polystyrene (EPS) is the most commonly used fresh food refrigeration insulation in Korea and Europe. Moreover, as the use of disposable packaging materials has increased significantly along with non-face-to-face delivery services since the COVID-19 crisis, social issues related to waste disposal are also being raised. Therefore, in this study, the life cycle of EPS boxes for fresh food is focused on the factors that have a large difference between incineration and landfill including recycling in Europe and Korea in the disposal process after use, and raw materials and energy in the manufacturing process, which account for a large portion of the environmental impact value. We tried to compare the environmental impact of evaluation. Overall, the raw material production stage, box manufacturing stage, and packaging stage have similar processes in Europe and Korea, but unlike Europe, Korea, which lacks landfills and incineration facilities, has focused on expanding the recycling rate. It was necessary to do an environmental impact assessment. Data affecting the environment were derived based on 2019 and 2020 data for Korea and 2017 and 2020 data for Europe. In order to predict the future environmental impact assessment, assumptions about the disposal rate in 2025 and 2030 were introduced and evaluated. As a result of this study, it was found that the raw material production stage of EPS boxes, which have similar processes in both Korea and Europe, has the greatest effect on the global warming effect of Korean EPS boxes. However, Korea, which has a relatively high recycling rate in the disposal process compared to incineration and landfill, showed better environmental performance than Europe in most impact indicators except freshwater eutrophication. In particular, Korea has increased the overall recycling rate compared to Europe by replacing various recyclable materials such as building materials and sundries with XPS (extruded polystyrene) recycled materials. In conclusion, it was found that increasing the recycling rate rather than incinerating and landfilling EPS boxes for fresh food in the domestic EPS industry has relatively less environmental load compared to Europe.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2000.03b
• /
• pp.325-330
• /
• 2000

In general steel sheet pile use the containment system, vertical barrier systems for waste disposal and landfill purposes, roads in excavation which have a more permanent character or temporary structure. The sheet pile joints between section of the wall are sealed with a filter material arid the resistance to seepage is a function of the type of material employed. The aim of this paper is to review a characteristic of permeability for Z type sheet pile by field test in various condition.

• Proceedings of the Safety Management and Science Conference
• /
• 2002.05a
• /
• pp.275-283
• /
• 2002

This study is focused on the calculation for optimum period for environmental logistics system to replace old truck. Companies throughout the world have recognized the importance of environmentalism and the role of logistics in structuring a corporate response to environmental issues like recycling, waste disposal, pollution, and many others. Reverse logistics, the term often used to represent the role of logistics in environmentalism, is gaining acceptance by firms.

• Journal of the Korean Data and Information Science Society
• /
• v.15 no.2
• /
• pp.317-329
• /
• 2004

The Web log has caught much attraction for tracing of customer activity. So many researches have been carried on it. As a result, Web log analysis solutions has been developed and launched lately. It has been in the spotlight to the website administrators and people in practical marketing business. In this paper, we made an analysis on the various behavior patterns of customers in cooperation with SAS/AF and SCL modules, based on development of GUI from SAS package for disposal of statistical data.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.15 no.25
• /
• pp.33-40
• /
• 1992

The analytic hierarchy process(AHP) is a multi-criteria decision methodology developed by T. L. Saaty(1980). The AHP presents flexible, easily understood wily to assist the decision-maker in formulating his problem in a logical and rational manner. This paper addresses the concept of AHP and its application in the selection of radioactive waste disposal concept in Korea.

• Magazine of RCR
• /
• v.18 no.1
• /
• pp.45-53
• /
• 2023