• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.136-146
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• 2023

Biological materials, such as stuffed specimens, can release various acids or volatiles. There has been no research carried out on the emission characteristics of organic compounds generated from the preservatives used in taxidermy specimens or associated manufacturing materials and methods. Therefore, in order to identify the organic compounds generated from taxidermy specimens, a degradation experiment was conducted on specimens for each material and for storage specimens. To produce Ogye chicken specimens, naphthalene and borax were used as preservatives, and planer sawdust, newspaper, and polystyrene foam were used as the core body materials. The deterioration experiment was conducted for 2 weeks in a high-temperature environment(50℃) and a high-humidity environment (95%), with an Ogye chicken specimen (year 2015) kept in an animal storage facility. Results indicated that the concentration of organic compounds generated by the specimen in the high-temperature environment tended to be greater than that in the high-humidity environment. The preservatives benzene, toluene, xylene, and p-dichlorobenzene were detected in the specimens using naphthalene, confirming that naphthalene is a major organic compound release factor, and the specimens that used sawdust, newspaper, and polystyrene foam also exhibited organic compounds. This appears to have been due to degradation of the material. In addition, ammonia was detected in the specimens for each material due to decay. In particular, the specimens using borax at high temperature were subject to approximately 9 times higher rates of ammonia-related deterioration than the specimens using naphthalene. These results can be considered to result from the prevention of biological damage through insecticidal effects by accelerating the sublimation of naphthalene in a high-temperature environment. Naphthalene is a potentially carcinogenic substance, and when used as a preservative, proper use management is required. Taxidermy specimens can release various organic compounds depending on the manufacturing techniques used, so a systematic preservation management plan is required that depends on conditions such as the applicable manufacturing materials and preservatives.

• Composites Research
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• v.29 no.4
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• pp.209-215
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• 2016

The failure of composite sandwich structures with thickness and material variation was studied. The main body of the structure is sandwich plate made of the carbon composite face and Aluminum honeycomb core. It is connected with composite laminated flange without core through transition region of tapered sandwich panel with foam core. Tension and compression tests were conducted for the total of 6 panels, 3 for each. Test results showed that the panels under compression are vulnerable to the face failure along the material discontinuity line between two different cores. However the failure load of which panel does not show such failure can carry 16% more load and fails in honeycomb core and face debonding. For the tensile load, the extensive delamination failure was observed at the corner radius which connects the panel and the flange. The average failure load for compression is about 7 times the tensile failure load. Accordingly, these sandwich structures should be applied to the components that endure the compressive loadings.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1C
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• pp.17-25
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• 2012

CLSM (Controlled Low Strength Material) using coal ash, which has the advantages of self-leveling, self-compacting, flowability, easy re-excavation, has been developed. In this study, CLSM additionally mixed with foaming agent for structural backfill material, aimed at lightness of materials, was developed called light-weight foamed CLSM. As the basic study of this material, to determine the optimum final mixing time and dilution ratio of existing light-weight foamed CLSM, flow, slurry unit weight and unconfined compressive strength test according to each impact factor were performed at the standard mix proportion. As the results of tests, CASE N (Final mixing time 4 min, dilution ratio 2%), CASE O (Final mixing time 3 min, foam agents ratio 3%, dilution ratio 2%) were satisfied with the standard of flow test (above 20cm), slurry unit weight test (12~15 $kN/m^3$) and unconfined compressive strength test (800 kPa~1200 kPa). These results will indicate the standard optimum final mixing time and dilution ratio of light-weight foamed CLSM for structural backfill.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.255-264
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• 2019

In this study, we conducted the hot box tests to compare the changes in thermal insulation for the four types of multi-layer thermal screens by the used period after collecting them from the greenhouses in the field when they were replaced at the end of their usage. The main materials for these four types of multi-layer thermal screens were matt georgette, non-woven fabrics, polyethylene (PE) foam, chemical cotton, etc. These materials were differently combined for each multi-layer thermal screen. We built specimens ($70{\times}70cm$) for each of these multi-layer thermal screens and measured the temperature descending rate, heat transmission coefficient, and thermal resistance for each specimen through the hot box tests. With regard to the material combinations of multi-layer thermal screens, thermal insulation can be increased by applying a multi-layered PE foam. However, it is considered that the multi-layered PE foam significantly less contributes to heat-retaining than chemical wool that forms an air-insulating layer inside multi-layer thermal screens. For the suitable heat-retaining performance of multi-layer thermal screens, basically, materials with the function of forming an air-insulating layer such as chemical cotton should be contained in multi-layer thermal screens. The temperature descending rate, heat transmission coefficient, and thermal resistance of multi-layer thermal screens were appropriately measured through the hot box tests designed in this study. However, in this study, we took into consideration only the four kinds of multi-layer thermal screens due to difficulties in collecting used multi-layer thermal screens. This is the results obtained with relatively few examples and it is the limit of this study. In the future, more cases should be investigated and supplemented through related research.

• Archives of Plastic Surgery
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• v.34 no.5
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• pp.587-592
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• 2007

Purpose: In case of postburn flexion contracture of the fingers, skin graft, geometrical relaxation techniques, local flap, and free flap have been used. Among these procedures, full-thickness skin grafts from the inguinal area are widely used to reconstruct a postburn flexion contracture in the fingers. But there are many esthetic and functional problems in this procedure. Especially, hyperpigmentation of the skin-grafted fingers poses a troublesome problem, particularly in the patients who have dark colored skin. To solve the problem, we have used pulp graft which was harvested from the lateral aspect of great toe. In the present study, we report pulp graft, with which we have obtained a good result in the treatment of postburn flexion contracture of the fingers. Methods: Between September of 2004 and August of 2006, great toe pulp graft was performed to 20 sites of 15 patients. After release of the postburn flexion contracture using Z-plasty, the composite tissue (pulp) harvested from the lateral aspect of great toe was grafted on the raw surface. Moisture dressing with ointment and foam dressing material was performed. Stratum corneum of the graft got stripped off in two to four weeks after pulp graft. The color of the pulp graft was slightly reddish, then it became similar to the adjacent tissue. Results: There was complete take in all the patients who were treated with pulp graft. Great toe pulp graft provided similar color and texture to the adjacent skin, high rate of graft take, and left only a minimal scar at donor site. Conclusion: Thick keratin layer and inelastic nature of the pulp make this type of the graft much easier and simpler, and ensure a better take. Pulp graft is useful method for the reconstruction of the postburn flexion contracture in fingers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.8
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• pp.1051-1057
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• 2013

In this study, an automatic surface-strain measurement system called "ASIAS-bio" has been developed. This system can be used even in cases in which it is very difficult to apply a regular grid pattern necessary for measuring surface-strain, such as curved or uneven surfaces; surfaces damaged by corrosion or contamination; or soft materials such as rubber, foam, and biological tissues. This system works independently of the measurement conditions including the material and its surface condition, grid pattern and size, grid marking method, and degree of deformation. A comparison between the strain distributions of the sheet metal parts measured by using this system and those obtained by a commercial system showed that this system was sufficiently reliable. In addition, the deformation of the swine joint capsule and human knee skin was measured by using this system to demonstrate its usefulness.

• Journal of the Korea Institute of Building Construction
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• v.20 no.3
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• pp.245-252
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• 2020

Synthetic resin formwork is made of lightweight high-density polyethylene(HDPE). This study used a process flow chart that satisfies the system boundary (such as Cradle-to- Product shipmen ) required by ISO FDIS 13352 to evaluate the entire process of synthetic resin foam using. The entire life cycle inventory (LCI) database calculated from input energy sources, materials used, transportation methods, and manufacturing processes at the system boundary was analyzed. Based on the environmental impact assessment index methodology of the Ministry of Environment from the LCI data analysis of synthetic resin formwork, the environmental impact assessment was carried out through classification, normalization, characterization, and weighting process. The experimental results are as follows the amount of CO₂ (carbon) emission considering the number of conversions was about 32% lower than that of the Euroform. This shows that the use of synthetic resin formwork reduces material production by half compared to Euroform and reduces CO₂ (carbon) emissions.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.4
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• pp.612-625
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• 2018

This study designed 16 kinds of basic structure and 4 kinds of modified structure for impact protection pads with a spacer fabric shape. The pad is a structure in which hexagonal three-dimensional units, composed of a surface layer and a spacer layer, are interconnected. Designed pads were printed with flexible $NinjaFlex^{(R)}$ materials using a FDM 3D printer. The printed pads were evaluated for impact protection performance, compression properties and sensory properties. The evaluation of the impact protection performance indicated that basic structures better than CR foam material at 20cm height were DV1.5, DX1.5, DX1.0, DV1.0 and HV1.5. The evaluation of the compression properties for the five types, with good results in the impact protection performance, indicated that DV1.0, DX1.0, DV1.5, HV1.5 and DX1.5 showed good results, respectively. The sensory evaluation of DV1.0, DX1.0, and DV1.5, which with good results when considering both the impact protection performance and the compression performance, showed that DV1.0 were the best for surface, flexibility, compression and weight. Therefore, DV1.0 is shown to be the best structure for protection pads.

• Journal of Animal Science and Technology
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• v.53 no.3
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• pp.253-259
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• 2011

The aim of this work was to determine the method and predict the optimum conditions for egg quality stored for 7 days when combination treatments of irradiation and chitosan coating were applied using response surface methodology (RSM). A central composite design was chosen for the RSM in this study and the factors were irradiation dose (0~2 kGy) and concentration of chitosan coating material (0~2%). Performance of the irradiation and chitosan coating were evaluated by analyzing the egg quality and functional property factors. The predicted maximum level of Haugh units and foaming ability calculated by a developed model were 74.19 at 0 kGy of irradiation with coating by 0.96% chitosan solution and 50.83 mm at 2.0 kGy with 1.01%, respectively. The predicted minimum value of foam stability and 2-thiobarbituric acid reactive substances (TBARS) value were 2.97 mm at 0.39 kGy with 0.21% and 0.54 mg malonaldehyde/kg egg yolk at 0 kGy with 0.90% of chitosan solution, respectively. Results clearly showed that gamma irradiation negatively affected the Haugh unit and TBARS but positively affected the foaming capacity. The estimated value from the developed model by RSM was verified by no statistical difference with observed value. Therefore, RSM can be a good tool for optimization and prediction of egg quality when 2 or more treatments are combined. However, one should decide the target quality first to achieve a successful implementation of this technology.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.186-191
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• 2000

We use so many plastic products in everyday. Because polymer materials have a lot of merits including low cost and easiness of forming, they are widely using at many manufacturing industries. Microcellular foaming process appeared at MIT in 1980's to save a quantity of material and increase mechanical properties. The information about the thickness of cavity plays an important role in appling microcellular foaming process to the conventional injection molding process. It is essential to make an effective foam. The goal of this research is to measure the relation between the change of cavity's thickness and foaming magnitude made after inserting a gas. R/t is a conception that indicate proportion between radius and thickness of cavity in mold system. By means of SEM observation of side surface of cavity sample, foaming magnitude of cavity is mold system. By means of SEM observation of side surface of cavity sample, foaming magnitude of polymer in microcellular foaming process is decreasing gradually as the value of R/t is increasing. The proposed foaming magnitude changes data of polymer in relation to mold system can be applied in more extensive injection molding process, such as optimum design of mold for microcellular foaming process.