• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.131-132
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• 2017

As the building is becomes bigger and larger, it can lead to big damage in case of fire. Also, tunnel, machine room and underground joint are spaces that can cause high temperature fire above 1,350℃ in case of fire. Therefore, a refractory material is need that can be withstand in high temperatures for long time. One side, the composition of oyster shell is CaCO₃ of 90% or more. It is expected that it will be possible to use it as a high calcium natural material which is the material of the refractory board. According to, Study on bending, compressive strength of mortar according to temperature and heating time change using oyster shell as aggregate the most commonly occurring particle sizes form 2.5mm to 5mm.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.122-123
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• 2017

As the building is becomes bigger and larger, it can lead to big damage in case of fire. Also, tunnel, machine room and underground joint are spaces that can cause high temperature fire above 1,350℃ in case of fire. Therefore, a refractory material is need that can be withstand in high temperatures for long time. One side, the composition of oyster shell is CaCO₃ of 90% or more. It is expected that it will be possible to use it as a high calcium natural material which is the material of the refractory board. According to, Study on bending, compressive strength of mortar according to temperature and heating time change using classified oyster shell as aggregate.

• Clean Technology
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• v.24 no.4
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• pp.315-322
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• 2018

Industrial use of waste oyster shells is limited because of requiring excessive energy for converting natural oyster shells in the form of calcium carbonate ($CaCO_3$) into calcium oxide (CaO) for this purpose. This study aimed to develop energy-saving process for producing solidifying agent using waste oyster shells for backfill materials. It was suggested that oyster shells were converted to calcium sulfates which were mixed with sodium hydroxide solution and red clay, forming solid specimen. The optimal concentrations of sulfuric acid for sulfation of oyster shell and sodium hydroxide to generate calcium hydroxide ($Ca(OH)_2$), were determined. Unconfined compressive strength of solid specimen increased with increasing the content of solidifying agent while it increased also with increasing ratio of natural oyster shells to coal ash. The result clearly demonstrates that solidifying agent consisting of sulfuric acid-treated oyster shell, coal ash, and sodium hydroxide solution, can be effectively utilized for preparing backfill materials using natural oyster shell and coal ash. Sulfuric acid-treated oyster shell-based solidifying agent has not been previously developed and will contribute to broaden industrial application of waste oyster shells.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.35-42
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• 2011

In order to understand effect of polycyclic aromatic hydrocarbon (PAH) on shell repair of the Pacific oyster, Crassostrea gigas, shell regeneration experiments were carried out using oysters drilled a hole on the right valve. The change of pH and hemocytic characteristics in both extrapallial fluid and hemolymph were observed during the shell repair. The thickness of mantle tissue was apparently decreased, while necrosis in epithelium and periostracal gland was increased in response to PAH exposure. Our finding suggested that PAH could adversely influence on shell repair.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.64-65
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• 2020

Oyster shells are difficult to grind, while oyster shell powders have coarse and coarse grains, whereas egg shell powder, the same high calcium material, has small and soft particles and has opposing properties. In order to study the change in flexural and compressive strength by designing different mixing ratios using 50% of oyster shell powder and egg shell powder as a filling material. As a result of the experiment, there is almost no difference in the result.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.43-44
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• 2017

In this study, mortar strength was measured by grinding oyster shell and changing the particle size distribution. For the experiment, the oyster shells were processed to a fine aggregate size of 10mm or less. In this experiment, seven particle size distribution conditions were selected and tested. Because oyster shells are different in density from sand, their volume ratios were calculated and converted to mass ratios of 1: 3. The strength test was carried out one day after the steam curing.

• Journal of Aquaculture
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• v.10 no.2
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• pp.97-103
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• 1997

Larval growth of the oyster, Crassostrea nippona, was investigated at the different conditions such as water volume, depth of culture vessel and initiative feeding time at $23^{\circ}C$. As a result, morphological changes were occurred during the early larval growth. That is, shell length was higher than shell height at the time of D-shaped larvae. Later, the length became equal to the hight when their shell length reached $127\mum$and then shell height increased rapidly. Some of pediveliger larvae with the size of $360\mum\;in\;shell\;length\;and\;385\mum$ in shell height began to temporarily settle on the substrate after 18 days. The result also indicated that the depth of culture vessel turned out to be an important factor rather than water volume for the larval growth. The fist feeding time of oyster larvae appeared to be the first day after fertilization.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.17-21
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• 2001

The object of this study is to find out the characteristics of waste oyster shells and determine the proper dosage of powdered waster oyster shells as the conditioning agent for water treatment sludge dewatering process. The large amount of waste oyster shells which discharges from the oyster farming, occurs serious environmental hazards. However, oysters shell contain large amount(about 38% by weight) of alkaline minerals, such as calcium and magnesium and so on, this natural material is thought to have the petential ability as a good conditioning agent. The results of this study are as follows. The optimum condition for improvement of the water treatment sludge dewaterability is when 6 g of waste oyster shell powder added to 200$m\ell$ of water treatment sludge. At optimum condition, the solid contents can reach to 31.78% and the specific resistance of conditioned sludge is 0.16$\times$10$^{8}$ sec$^2$/g. However, exceeding the of powdered waste oyster shell is needed to get the effective result. Consequently, the waste oyster shell can be a recyclable material to improve the dewaterability of water treatment sludges.

• Journal of Biosystems Engineering
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• v.22 no.2
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• pp.237-246
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• 1997

Shucking(removing the meat from the shell) an oyster requires that the muscle attachments to the two shell valves and the hinge be severed. Described here is the computer vision software needed to locate the oyster hinge line so it can be automatically severed, one step in development of an automated oyster shucker. Oysters are first prepared by washing and trimming off a small shell piece on the oyster hinge end to provide access to the outer hinge surface. A computer vision system employing a color video comera then gabs an image of the hinge end of the oyster shell. This image is Processed by the computer using software. The software is a combination of commercially available and custom written routines that locate the oyster hinge. The software uses four feature variables, circularity, rectangularity, aspect-ration, and Euclidian distance, to distinguish the hinge object from other dark colored objects on the hinge end of the oyster. Several techniques, including shrink-expand, thresholding, and others, were used to secure an image that could be reliably and efficiently processed to locate the oyster hinge line.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.287-293
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• 2012

This paper has dealt with the probability of oyster shell desiccant cooling system driven by renewable energy of photo-voltaic effect. For this, fundamental experiments have been carried out focusing on the observation of dehumidifying effect of oyster shell and peltier elements used for air conditioning system. From this study, it is found that oyster shell has sufficient probability for using as a desiccant in air-conditioning system. Moreover, the heat releasing device(peltier element) can be used with direct current from PV cells so the system can be operated with high efficiency. As a result, the absolute humidity in a test chamber was reasonably controlled by oyster shell and peltier elements. Also the photo-voltaic energy from sun was enough for running power of this system.