• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.418-423
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• 2018

Recently, research and development of high-value leisure vessels has been carried out in Korea to revitalize the marine leisure industry and tap into the global maritime leisure market. FRP composite materials, which have excellent physical properties and are available for the manufacture of light hulls, are used widely. One of the most important design technologies is to secure structural safety of leisure vessels made from FRP composite materials. In this study, the structural strength was assessed for the design of an 8-meter high-speed planing leisure boat made from FRP composite materials. The design loads to verify the structural safety were calculated according to the rules for the classification of high speed light craft (KR, 2015), and structural analysis was conducted using a finite element model composed of an isotropic shell element, which has equivalent bending rigidity with the FRP sandwich panel. The analysis results were compared with the results of the strength test for fabricated specimens, and all internal structural components are sufficiently satisfied with the structural strength.

• Herbal Formula Science
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• v.30 no.4
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• pp.281-291
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• 2022

Objectives : In this study, acute oral toxicity test of pomace Schisandra chinensis extracts was conducted in order to up-cycling to a high value-added industry using by-products discarded in the production process of Schisandra chinensis products and active ingredients such as dibenzocyclooctadiene lignans in Schisandra chinensis. Methods : Pomace Schisandra chinensis extracts were orally administered to SD-rats(female, n=3) without a control group according to the 'OECD guidelines'. After, mortality and clinical signs were observed, and the deceased animals were subjected to an autopsy. In addition, acute oral toxicity test was sequentially performed in step I (300 mg/kg), step II(300 mg/kg), step III(2,000 mg/kg), and step IV(2,000 mg/kg) according to the mortality. Results : There were no abnormalities caused by pomace Schisandra chinensis extracts in step I and step II. However, one animal each died in step III and step IV. In addition, clinical signs(salivation, decrease in food intake, prone position, decrease of locomotor activity, loss of locomotor activity, convulsion, hypothermia, lacrimation, staining around mouth, soiled perineal region, reddish urine, chromaturia, decrease of fecal volume, lying on side, blackish stool, no stool, compound-colored stool, refusal to feed, excitement, hypersensitivity, rigidity, dorsal position, etc.) were observed. But, no clinical signs were observed from 5th day, and experiment animals recovered completely. Conclusions : As a result of this study, pomace Schisandra chinensis extracts may exhibit acute toxicity at concentrations of 2,000 to 5,000 mg/kg, and the GHS classification was designated as 'Category 5'.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1259-1266
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• 2022

Recently, due to the specialization of structural design standards and evaluation methods, the classification rules are being integrated. A good example is the common international rules (CSR). However, detailed regulations are presented only for the cargo hold area where the longitudinal load is greatly applied, and no specific evaluation guidelines exist for the bow and stern structures. Structural design of the mentioned area is carried out depending on the design experience of the shipbuilder, and because no clear standard exists even in the classification, determining the root cause is difficult even if a structural damage problem occurs. In this study, an engineering-based solution was presented to identify the root cause of representative cases of buckling damage that occurs mainly in the stern. Buckling may occur at the panel wall owing to hull girder bending moment acting on the stern structure, and the plate thickness must be increased or vertical stiffeners must be added to increase the buckling rigidity. For structural strength verification based on finite element analysis modeling, reasonable solutions for load conditions, boundary conditions, modeling methods, and evaluation criteria were presented. This result is expected to be helpful in examining the structural strength of the stern part of similar carriers in the future.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.597-602
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• 2008

Purpose: Presently, silicone rubber is chosen most frequently for nasal augmentation. However, there is a possibility of extrusion with this material. Sometimes, noses are prone to be traumatized, and then silicone rubber has a possibility of deformity or deviation resulting in trauma. We experienced cases with complications and traumatic deformities after the augmentation rhinoplasty. Methods: A retrospective review was performed to determine the characteristics of the implanted nasal silicone prosthesis after trauma. The patients' data such as deviation of implant, shape of fracture, age and sex of the patient, time of treatment, operative methods were reviewed. From March 2001 to March 2008, this study was performed in 30 patients. The patients were 25 females and 5 males, from 24 to 60 years of age, with an average of 42. All patients had previous augmentation rhinoplasty with silicone implant. Results: All of the 30 patients were confirmed as deviation of silicone and nasal bone fractures in the facial bone CT scan. The most common cause of fracture was traffic accident. The classification of nasal trauma after augmentation was done by facial bone CT. Class I: Deviation of silicone without nasal bone fracture without extrusion(12 cases, 40%), Class II: Deviation of silicone without nasal bone fracture and with extrusion(4 cases, 13%), Class III: Deviation of silicone with nasal bone fracture and without extrusion(8 cases, 27%), Class IV: Deviation of silicone with nasal bone fracture and with extrusion(3 cases, 10%), Class V: Mild deviation of silicone with nasal bone fracture(3cases, 3%). Specially, the comminuted or trapezoid nasal fracture was confirmed in 11 cases(Class III, IV). Conclusion: The problems of silicone implant have generally been related to foreign body reactions, rigidity of the material, encapsulation, infections, and extrusion. We experienced 11 cases of comminuted or comminuted trapezoid shaped fracture below nasal implant. So, we think this phenomenon could be used in late problem of silicone implant.