• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.34.1-34.14
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• 2015

Background: Over the past 30-40 years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8 years. Methods: Mandibular reconstruction (8-10 years ago) was performed with pure (99.99 %) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Results: Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants. Conclusions: The surface morphology and the structure were not changed after 8 years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates.

• Corrosion Science and Technology
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• v.9 no.5
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• pp.196-200
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• 2010

Recently porous metal has been used as supporting metal in planar type SOFC. In order to search optimum alloys for porous metal support and estimate the stability of metal-supported SOFC at high temperature, it is necessary to investigate the oxidation behaviors of porous material for metal support in comparison with dense material. Oxidation tests of porous and dense stainless steels were conducted at $600^{\circ}C$ and $800^{\circ}C$. Since the specific surface area of porous material is much larger than that of dense material, surface area should be considered in order to compare the oxidation rate of porous stainless steel with that of dense stainless steel. The specific surface area of porous body was measured using image analyzer. The weight gain of porous stainless steel was much greater than those of dense stainless steels due to its larger specific surface area. considering the specific surface area, the oxidation rate of porous stainless steel is likely to be the same as that of dense stainless steel with the same surface area. The change in chromium content in stainless steel during oxidation was also investigated. The experimental result in chromium content in stainless steel during oxidation corresponded with the calculated value. While the change in chromium content in dense stainless steel during oxidation is negligible, chromium content in porous stainless steel rapidly decreases with oxidation time due to its large specific surface area. The significant decrease in chromium content in porous stainless steel during oxidation may affect the oxidation resistance of porous stainless steel support and long term stability of metal-supported SOFC.

• Selected Papers of The Society of Naval Architects of Korea
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• v.2 no.1
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• pp.140-155
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• 1994

The hydrodynamic problem is treated here when a pressurized bag is submerged partially in the water and the end points of it oscillate. SES(Surface Effect Ship) has a bag filled with pressurized air at the stern in order to prevent the air leakage, and the pitch motion of SES is largely affected by the hydrodynamic force of the bag. The shape of a bag can be determined with the pressure difference between inside and outside. Once the hydrodynamic pressure is given, the shape of a bag can be obtained, however in order to calculate the hydrodynamic pressure we should know the shape change of the bag, and vice versa. Therefore the type of boundary condition on the surface of a bag is a moving boundary like a free surface boundary. The present paper describes the formulation of this problem and treats a linearized problem. The computations of the radiation problem for an oscillating bag are shown in comparison with the case that the bag is treated as a rigid body. The hydrodynamic forces are calculated for various values of the pressure inside the bag and the submerged depth.

• International Journal of Automotive Technology
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• v.3 no.3
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• pp.117-122
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• 2002

Joint stiffness can affect the vibration characteristics of car body structures. Therefore, it should be included in vehicle system model. In this paper, a numerical approximation of joint stiffness is presented considering joint flexibility of thin walled beam-jointed structures. Using the proposed method, it is possible to optimize joint structures considering the change of section shapes in vehicle structures. The numerical approximation of joint stiffness is derived using the response surface method in terms of beam section properties. The study shows that joint stiffnesses can be effectively determined in designing vehicle structures.

• Fashion & Textile Research Journal
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• v.20 no.3
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• pp.245-256
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• 2018

This study considers application types and meanings of fashion engineering by analyzing CuteCircuit. The conclusions of this study are as follows. The application type of fashion engineering shown in CuteCircuit is first, electronic fashion, which attaches LED or WL on the surface of clothes to express the decorative function in clothes as optical light change, ultimately performing one-dimensional function. Second, interactive fashion is a medium in which clothing connects human beings with other human beings with sensors that can recognize the changes in tactile or movement with the wearer or with a light source that can visualize the emotional changes of the wearer. Third, scientific fashion has emerged as a new type of fashion in which new materials introduced in the field of engineering are fused with clothing to expand functionality and aesthetics. The meanings of fashion engineering in CuteCircuit is first, trying to conceptualize a new beauty as an open fashion that can freely change with the creation of a dual beauty by combining analog and digital sensibility. Second is the external representation of human psychological change or emotional exchange, which helps to form a consensus by understanding and exchanging emotions of different people. Third, reorganization of apparel pursuing integrated value appeared. Clothing, as a connection body in which the human body and the mechanical environment are combined with each other, is reestablished as a product of variable body that can embody an integrated value that includes various characteristics and can be diversified appropriately in any circumstance.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.158-165
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• 1998

This study was undertaken to observe the effects of the antineoplastic agent, 5-Fluorouracil(5 FU) on the hair in Sprague-Dawley white rats. Twenty four sprague-Dawley strain white rats, each weighing about 150-200 grams were used and divided into control and experimental groups. In the experimental group, eighteen rats were injected intraperitonially with 60 mg of 5-FU per killogram body weight with one time per two days, Six rats were injected with 0.5 cc of normal saline solution intraperitoneally as a placebo on this control group. Rats were serially sacrificed on the first, third, fifth, seventh, tenth and fourteenth day after 2 times of injection of 5-FU and saline. The hair were obtained and observed SEM. After examination and comparision of all specimens, the results of this study were as follows: 1. In the control group, the scale and cuticle of hair was observed smooth surface and equal interval 2. In the experimental group, the first day, scale change was seen from body of hair and crack was seen. from fifth day, and irregular scale and cuticle of hair was seen from 10, 14 days 3. The apperance of root of hair was not almost change From above results, 5-Fluorouracil was more effective on the hair body. The change was begun from first day and crack of scale was seen from fifth day and irregular scale and cuticle of hair was seen from 10,14 days. The.

• Journal of the Korean institute of surface engineering
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• v.28 no.4
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• pp.207-218
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• 1995

Tungsten(W) metal has excellent properties in heat-resistance, corrison-resistance and impact-resistance but W-Metal is hard to sinter because higher than $2,000^{\circ}C$ is required to sinter W-powder. Con-sequently, a deposit technique of Nikel Phosphorus(NiP) on W-powber by the liquid reduction precipitation method was performed. Sintering temperature of the resulting W-NiP composite was lowered around to $1,000^{\circ}C$, and the mechanical properties of the sintered body was studied. The most suitable conditions for NiP thin film deposit on W-Powder by the liquid reduction precipitation method, which are composition, concentration, pH and temperature of the liquid reduction solution, were considered. The activated sintering was carried out in a reducing condition furnace. Components and properties of the sintered body were investigated by the density and the hardness measurements, X- ray diffraction analysis, and microscopic photographs of the surface. Quantity of NiP thin film on W-powder could be varied by the change of the liquid reduction solution composition. The sintering temperature of W-NiP composite powder is lowered to $950^{\circ}C$ from $2,000^{\circ}C$ and the hardness is increased (ca. 720 Hv). Large shrinkage could be observed since density was increased from 5.5 to 11.0 g/$cm^2$ which 86.2% of theoretical density. W metal and $Ni_3P$ crystal were detected through X-ray diffraction on the sintered body. Perfectly activated sintering was observed by microscopic photographs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.103-110
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• 2019

Recently, Korea has been affected by extreme weather events including extended summers and increased temperatures caused by global warming and climate change. Environmental temperature is especially important to the livestock industry because it is closely related to livestock productivity. This study was conducted to investigate the influence of different environmental temperatures on respiration rate, rectal temperature and body-surface temperature in finishing pigs. Pigs ($98.3{\pm}6.6kg$) were housed in individual cages inside an experimental chamber and exposed continuously to one of five environmental treatments ($22^{\circ}C$, $24^{\circ}C$, $26^{\circ}C$, $28^{\circ}C$, $30^{\circ}C$) for 10 days without providing additional rest time. Feed and water intake, respiration rate, rectal temperature and body-surface (head, ear, neck, back, side) temperature were measured two times daily during the experimental period. A significant increase in respiration rate from $26^{\circ}C$ and in body-surface temperature from $24^{\circ}C$ (p<0.05) was observed. At $30^{\circ}C$, the respiration rate had almost doubled and the body-surface temperature increased by about $5^{\circ}C-7^{\circ}C$. Moreover, ear skin temperature was very sensitive to environmental temperature. However, feed intake, water intake and rectal temperature did not change significantly during the experiment.

• Journal of the Korean Home Economics Association
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• v.35 no.4
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• pp.79-94
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• 1997

This study was performed to develop a basic stacks pattern for middle-aged women reflecting the characteristics of their lower body types. Anthropometric measurements using sliding guage method were carried out for 4 women 40's For the analysis of the lower body types horizontal and vertical section maps obtained by sliding gauge method and 2 indices were produced. Based on the slacks construction components produced by the drafts of their lower body surface experimental slacks pattern was designed. Multiple comparison test was used to compare 3 existing slacks patterns with the experimental pattern. 1. The results of the body section map analysis were as follows: 1) In the frontal view silhouette of vertical section maps there were less individual differences in items with skeleton landmarks than those without them. 2) In the shape of horizontal section maps waist section represented more round shape than the others and thigh maximum width section had the flattest shape. Flat ratios(depth/width) of subjects were much higer than those of young women which clarified the change of depth was bigger than that of width with aging process. 2. The slacks construction components for pattern drafting were as follows: 1)Ease amount of waist was 0.5cm and front and back waist girth difference was 1.2cm Ease amount of hip was 1,8cm and front and back hip girth difference was 0.7 cm 2) The amount of dart intake incresed in the order of side(4cm) back(3,6cm) from (2.8cm) The length of dart leg incresed in the order of front side back.

• Journal of the Korean Home Economics Association
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• v.30 no.3
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• pp.63-77
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• 1992

The purpose of this study is to improve clothing construction by analyzing form variation of upper trunk & upper arms with the use of plaster cast. Experimental research was performed by plaster gypsum method. The subjects were males between age 21 and 25, classified Standard somatotype by their bust size and Rorher Index. Arm movements were consisted of 5 types(0$^{\circ}$, 45$^{\circ}$, 90$^{\circ}$, 135$^{\circ}$, 180$^{\circ}$) to each vertical motion in front. The statistical analyses used in this study were mean, standard deviation, repeated mesure design. The result obtained from this study were as follows; 1. As a result of investigating into the rate of the expantion and contraction of basic body-surfact-lines, the side seam length showed the maxium rate of expantion in 180$^{\circ}$ degrees, the shoulder length showed the maxium contraction in the same degrees. 2. The variation of the upper part of the body form by increasing the upper limb motions, shoulder point was moved to be the inside or upside. And the anterior armfit point, posterior armfit point and armfit point were moved to upside. The form of the armhole-line in Drafts of a body surface was differently changed by increasing the movements. 3. Increasing the upper limb motions, the height of sleeve cap decresed and width of the sleeve decreased but girths of the sleeve cap was not show consistant change.