• Hwankyungkyoyuk
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• v.24 no.2
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• pp.54-69
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• 2011

The objectives of this study were to investigate the need for school uniform recycling and to review the school uniform recycling-related education. 231 female high school students were asked to answer regarding the wearing state of school uniform and their satisfaction level. 10 subjects in middle school technology/home economy were evaluated. As the result, the students wore 1~2 pieces of school uniform, which showed that it was hard to keep them clean by washing them often. The satisfaction level of school uniform was not high, The lowest item was the price. Therefore, to increase the satisfaction level of the school uniforms and also to increase the sanitary level of the school uniforms, it was advisable to purchase a recycled school uniform at cheaper prices to have an extra set. For a vitalization of the recycled school uniforms, the middle school technology/home economy subjects were reviewed. In the topic of "clothing acquisition plan and purchase", the themes of planned purchase, overconsumption of clothing and environmental pollution were discussed and included preferable behaviors for disposal. The topic of "clothing manufacturing and recycling" listed recycling the clothes that are not worn or exchanging them with neighbors as well as suggesting methods to illicit environment-friendly behaviors and carrying them out. However, some textbooks only briefly explained the methods of recycling and more detailed and practical methods need to be suggested in the curriculum. In addition, the contents regarding the environment in the clothing topic need to be supplemented more and more changes, such as related education plans or data development, are required. The objectives of this study were to investigate the need for school uniform recycling and to review the school uniform recycling-related education. 231 female high school students were asked to answer regarding the wearing state of school uniform and their satisfaction level. 10 subjects in middle school technology/home economy were evaluated. As the result, the students wore 1~2 pieces of school uniform, which showed that it was hard to keep them clean by washing them often. The satisfaction level of school uniform was not high, The lowest item was the price. Therefore, to increase the satisfaction level of the school uniforms and also to increase the sanitary level of the school uniforms, it was advisable to purchase a recycled school uniform at cheaper prices to have an extra set. For a vitalization of the recycled school uniforms, the middle school technology/home economy subjects were reviewed. In the topic of "clothing acquisition plan and purchase", the themes of planned purchase, overconsumption of clothing and environmental pollution were discussed and included preferable behaviors for disposal. The topic of "clothing manufacturing and recycling" listed recycling the clothes that are not worn or exchanging them with neighbors as well as suggesting methods to illicit environment-friendly behaviors and carrying them out. However, some textbooks only briefly explained the methods of recycling and more detailed and practical methods need to be suggested in the curriculum. In addition, the contents regarding the environment in the clothing topic need to be supplemented more and more changes, such as related education plans or data development, are required.

• Economic and Environmental Geology
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• v.51 no.2
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• pp.77-85
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• 2018

There would be a possibility of uranium contamination around the nuclear power plants and the underground waste disposal sites, where the uranium could further migrate and diffuse to some distant places by groundwater. It is necessary to understand the biogeochemical behaviors of uranium in underground environments to effectively control the migration and diffusion of uranium. In general, various kinds of microbes are living in soils and geological media where the activity of microbes may be closely connected with the redox reaction of nuclides resulting in the changes of their solubility. We investigated the adsorption and precipitation behaviors of dissolved uranium on some solid materials using hydrogen gas as an electron donor instead of organic matters. Although the effect of hydrogen gas did not appear in a batch experiment that used granite as a solid material, there occurred a reduction of uranium concentration by 5~8% due to hydrogen in an experiment using bentonite. This result indicates that some indigenous bacteria in the bentonite that have utilized hydrogen as the electron donor affected the behavior (reduction) of uranium. In addition, the bentonite bacteria have showed their strong tolerance against a given high temperature and radioactivity of a specific waste environment, suggesting that the nuclear-biogeochemical reaction may be one of main mechanisms if the natural bentonite is used as a buffer material for the disposal site in the future.

• Tunnel and Underground Space
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• v.20 no.6
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• pp.475-490
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• 2010

The analysis of slope stability was performed from seven sites among total eleven sites of waste rock which are divided into two objects (mullock-pile and rock mass) according to the location of dumping-dropping point in L limestone Mine. The analysis of circular failure using Bishop's simplified method and the finite element method for mullock-pile slopes were adopted. For rock mass slopes, identification of failure modes on stereonet projection was determined, thereby limit equilibrium analysis was applied to obtain the safety factor of slopes and the finite element method was used to understand overall behavior of slope. Phi-c reduction method was used to calculate the safety factor of slopes through the finite element method. In mullock-pile slope of zone D and rock slopes of zone F and G, the assurance of slope stability was difficult, and the plans to assure the stability of slopes were proposed on the basis of the analysis of slopes at disposal sites of waste rock. Therefore, the method of piling with waste rock by dozer pushing after dumping for mullock-pile slope of zone D is required, and the method of piling after moving to the place which has no fault zone for rock slope of zone F and G is recommended.

• Tunnel and Underground Space
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• v.33 no.4
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• pp.228-243
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• 2023

Bentonite is widely recognized and utilized as a buffer material in high-level radioactive waste repositories, mainly due to its favorable characteristics such as swelling capability and low permeability. Bentonite buffers play an important role in ensuring the safe disposal of radioactive waste by providing a low permeability barrier and effectively preventing the migration of radionuclides into the surrounding rock. However, the long-term performance of bentonite buffers still remains a subject of ongoing research, and one of the main concerns is the erosion of the buffer induced by swelling and groundwater flow. The erosion of the bentonite buffer can significantly impact repository safety by compromising the integrity of buffer and leading to the formation of colloids that may facilitate the transport of radionuclides through groundwater, consequently elevating the risk of radionuclide migration. Therefore, it is very important to numerically quantify the erosion of bentonite buffer to evaluate the long-term performance of bentonite buffer, which is crucial for the safety assessment of high-level radioactive waste disposal. In this technical note, Two-region model is introduced, a proposed model to simulate the erosion behavior of bentonite based on a dynamic bentonite diffusion model, and quantitative evaluation is conducted for the bentonite buffer erosion with this model.

• Tunnel and Underground Space
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• v.28 no.5
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• pp.400-425
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• 2018

This study presents the research results and current status of the DECOVALEX-2019 project Task B. Task B named 'Fault slip modelling' is aiming at developing a numerical method to simulate the coupled hydro-mechanical behavior of fault, including slip or reactivation, induced by water injection. The first research step of Task B is a benchmark simulation which is designed for the modelling teams to familiarize themselves with the problem and to set up their own codes to reproduce the hydro-mechanical coupling between the fault hydraulic transmissivity and the mechanically-induced displacement. We reproduced the coupled hydro-mechanical process of fault slip using TOUGH-FLAC simulator. The fluid flow along a fault was modelled with solid elements and governed by Darcy's law with the cubic law in TOUGH2, whereas the mechanical behavior of a single fault was represented by creating interface elements between two separating rock blocks in FLAC3D. A methodology to formulate the hydro-mechanical coupling relations of two different hydraulic aperture models and link the solid element of TOUGH2 and the interface element of FLAC3D was suggested. In addition, we developed a coupling module to update the changes in geometric features (mesh) and hydrological properties of fault caused by water injection at every calculation step for TOUGH-FLAC simulator. Then, the transient responses of the fault, including elastic deformation, reactivation, progressive evolutions of pathway, pressure distribution and water injection rate, to stepwise pressurization were examined during the simulations. The results of the simulations suggest that the developed model can provide a reasonable prediction of the hydro-mechanical behavior related to fault reactivation. The numerical model will be enhanced by continuing collaboration and interaction with other research teams of DECOLVAEX-2019 Task B and validated using the field data from fault activation experiments in a further study.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.2 no.4
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• pp.135-151
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• 2007

A 5 days working system and a 6 days working system will be put in force at a food service consumption behavior of company workers. As a 5 days working system have adopted company, which the number of employee is more than 50, from July 1, 2007. The purpose of this paper is to study the In food service consumption behavior of company workers. There is no doubt that it is only way of surviving In current society to analyze the change of social situation and actively cope with the development. Especially, in the field of restaurant industries, they have to be equipped with a great store of experience and skill, theory and practical business, pertinent and rapid disposal. Consequently, it is very important to know the objective and practical knowledge for the restaurant industries trend by having a through grasp of the need of consumer and their propensity to consume. In order to study motives of eating-out and restaurants selection, office workers, who live in the national capital region, are interviewed. The period of interview is from Oct 1 to Nov 20, 2007. According to the result of interview, The most workers prefer to eating-out on week with family and friends. But family is eating-out the more preference to weekend compare to friends. And it is deduced that restaurant near tourist resorts or outside the city rather than in downtown will be prosperous with this result. That is to say, workers go out to eat delicious food regardless of traffic problem and distance, with the increase of national income and the car holding. This paper is worthy of notice in terms of trying to find the relevance between the working system and the restaurant industries development. In after research, I expect the more synthetic and deeper study should be made though the more technical methods.

• Journal of the Korean Electrochemical Society
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• v.26 no.1
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• pp.11-18
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• 2023

As the use of lithium-ion secondary batteries is rapidly increasing due to the rapid growth of the electric vehicle market, the disposal and recycling of spent batteries after use has been raised as a serious problem. Since stored energy must be removed in order to recycle the spent batteries, an effective discharging process is required. In this study, graphite and NCM622 were used as active materials to manufacture coin-type half cells and full cells, and the electrochemical behavior occurring during overdischarge was analyzed. When the positive and negative electrodes are overdischarged respectively using a half-cell, a conversion reaction in which transition metal oxide is reduced to metal occurs first in the positive electrode, and a side reaction in which Cu, the current collector, is corroded following decomposition of the SEI film occurs in the negative electrode. In addition, a side reaction during overdischarge is difficult to occur because a large polarization at the initial stage is required. When the full cell is overdischarged, the cell reaches 0 V and the overdischarge ends with almost no side reaction due to this large polarization. However, if the full cell whose capacity is degraded due to the cycle is overdischarged, corrosion of the Cu current collector occurs in the negative electrode. Therefore, cycled cell requires an appropriate treatment process because its electrochemical behavior during overdischarge is different from that of a fresh cell.

• Tunnel and Underground Space
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• v.32 no.1
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• pp.30-58
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• 2022

The deep geological repository for high-level radioactive waste disposal is a multi barrier system comprised of engineered barriers and a natural barrier. The long-term integrity of the deep geological repository is affected by the coupled interactions between the individual barrier components. Erosion and piping phenomena in the compacted bentonite buffer due to buffer-rock interactions results in the removal of bentonite particles via groundwater flow and can negatively impact the integrity and performance of the buffer. Rapid groundwater inflow at the early stages of disposal can lead to piping in the bentonite buffer due to the buildup of pore water pressure. The physiochemical processes between the bentonite buffer and groundwater lead to bentonite swelling and gelation, resulting in bentonite erosion from the buffer surface. Hence, the evaluation of erosion and piping occurrence and its effects on the integrity of the bentonite buffer is crucial in determining the long-term integrity of the deep geological repository. Previous studies on bentonite erosion and piping failed to consider the complex coupled thermo-hydro-mechanical-chemical behavior of bentonite-groundwater interactions and lacked a comprehensive model that can consider the complex phenomena observed from the experimental tests. In this technical note, previous studies on the mechanisms, lab-scale experiments and numerical modeling of bentonite buffer erosion and piping are introduced, and the future expected challenges in the investigation of bentonite buffer erosion and piping are summarized.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.95-103
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• 2002

The consumption in the clothing's living has been diversified and rich by the increase in pay, the ostentatious propensity to consume and the diversification of distribution on structure in accordance with the advance of clothing industries, etc. The clothing, however, was not used properly due to the thoughtless purchase, the sudden change of fashion and the difficulty in the use and management of clothing. Most rural communities, furthermore, have the poor market, and the unreasonable management could be often observed, e.g., some people don't follow the care label or burn the clothing to waste. This study was conducted to provide the tool measuring the standardized clothing management behaviors so that the systematic and effective instruction could be achieved to improve the living standards 623 rural and urban housewives to develop the tool measuring the standardized clothing management to compare and measure the effect of before and after the education and guide all the way. And then, we developed the standardized measurement tool consisting of 6 parts of 60 questions after analyzing the validation and reliability of the questions. As a result of analyzing the validation and reliability of the developed tool, each Conbach alpha value of clothing living showed the good reliability; the value of the purchase plan was 0.76, the purchase was 0.83, the wear was 0.80, the management was 0.84, the storage was 0.83, and the disposal was 0.74, which indicated that it was able to use as a standardized tool.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.161-170
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• 2017

Research should explore techniques that will allow disposal of the dead to help the living by providing public space, protecting the environment, and contributing to economic development. Its design might bring a cemetery back into community life and make a present of a park. This new design for a cemetery can provide a structural solution for limited burial sites on the metropolitan area of Korea. It is based on the shared sense of a cemetery, a joint ownership or co-ownership of the space of a cemetery. FBS model by Gero[1] is used for engineering a cemetery design development. This framework contains a dynamic character of the context where such design takes place among its function, behavior and structure. This study suggests a new cemetery concept rather than a simple civil engineering work for a cemetery. It aims for people to have a new perspective on a cemetery and contribute to the society through an eco-friendly business model, so FBS may be an adequate model for such design. It can be one of the innovative business models and designs for engineering cemeteries, implementing sustainable environment and changing the design from a cemetery to a natural park.