• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.192-203
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• 2004

The AA5182/polypropylene/AA5182 (AA/PP/AA) sandwich sheets have been developed for the application for automotive body panels in the future light weight vehicles with significant weight reduction. It has been reported that the 5182 aluminum sheet shows Luders band because of dissolved Mg atoms that causes fabrication process problem, especially surface roughness. The examination of serration behavior has been made after the tensile deformation of the AA/PP/AA sandwich sheets as well as that of the 5182 aluminum skin at room and elevated temperatures. All sandwich sheets and the 5182 aluminum skin showed serration phenomena on their flow curves. However, the magnitude of the serration was significantly diminished in the sandwich sheet with the high volume fraction of the polypropylene core. According to the results of the surface roughness analysis after the tensile test, the sandwich sheet evidently showed lower Luders band depth than the 5182 aluminum skin. Strain rate sensitivity, m-value, of the 5182 aluminum skin was -0.006. By attaching this skin with polypropylene core which has relatively large positive value, 0.050, m-value of the sandwich sheets was changed to the positive value. The serration reduction of the sandwich sheets was quantitatively investigated in the point of the effect on the polypropylene core thickness variation, that on the strain rate sensitivity. It was found that the serration reduction degree from the experimental results of the sandwich sheet was higher than that from the calculated values by the rule of mixture based on volume fraction of the skins and the core.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.1
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• pp.142-148
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• 1995

In this study, FVM (Finite Volume Method) which is one of the 2-dimensional numerical approach has been conducted to anticipate the temperature distribution between skin and clothes by the change of air temperature and fabric characteristics including fabric thickness. Several experimental works have been done to understand the thermal insulation effect (If fabrics on a human body by measuring the averaged temperature in the air layer between skin and clothes or by measuring the thermal resistance of fabrics. However, the formal method is inconvenient to measure the temperature distribution in the air layer to evaluate the insulation rate of the clothes on the skin because the real size of the clearance between skin and the clothes is too small to place the temperature sensor, and in the Tatter method the relationship between human body and the fabrics are ignored. However, the numerical method will be very effective and economical way to evaluate the insulation efficiency of clothes when the computational result is in the reliable range. As the result of this study, the temperature change in the sir layer between skin and clothes was linear to the fabric thickness and this result coincides with many previous experimental results. Moreover, it is possible to predict the optimum fabric thickness for the best thermal insulation in the air layer between skin and clothes.

• Physical Therapy Korea
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• v.14 no.3
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• pp.1-8
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• 2007

The purpose of this study was to determine whether aromatherapy massages with manual lymph drainage (MLD) are significantly more effective than sham massages with MLD in reducing edematous limb volume in lymphedema. This study was performed on 46 patients who had developed unilateral upper or lower lymphedema. Twenty-three patients served as the experimental group and were treated with complex decongestive physiotherapy (CDP) applications including aroma massages with MLD, multi layered compression bandages, remedial exercises and skin care. Twenty-three patients in the control group were treated with CDP applications including sham massages with MLD, bandages, exercises and skin care. Patients undergo a therapy program once a day; 5 days a week for 2 weeks. Percentage excess volume (PEV) and body mass index (BMI) were recorded before and after treatment. PEV and BMI were significantly decreased before and after treatment in the experimental as well as in the control groups (p<.05). However, the percentage excess volume and BMI were not significantly improved after treatment between the two groups (p>.05). This study there suggests that aroma massages is not effective in the edema of patients with lymphedema.

• International Journal of High-Rise Buildings
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• v.1 no.2
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• pp.125-129
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• 2012

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.87-107
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• 2003

It was demonstrated that Transactivating transcriptional activator(TAT) protein from HIV-1 shown to enter cells when added to the surrounding media. TAT peptide chemically attached to various proteins was able to deliver these proteins to various cell and even in tissues in mice with high levels in heart and spleen. In this study, the tripeptide GKH(Glycine-Lysine-Histidine) derived from Parathyroid hormone (PTH), which was known as lipolytic peptide, is attached to 9-poly Lysine(TAT) to be used as a cosmetic ingredient for slimming products. When Glycerol release, expressed as extracellular glycerol concentration, is lipolysis index, TAT-GKH at $10^{-5}$mo1/L induces approximately 41.5% maximal lipolytic effects in epididymal adipocytes isolated from rats, compared with basal lipolysis. Epididymal adipose tissues of male rats is assessed ex vivo by microdialysis. Probes are perfused with Ringer solution in which increasing concentrations of TAT-GKH. The perfusion of TAT-GKH induces lipolytic effect. Penetration study showed that TAT-GKH efficiently elevates 36 times higher penetration into the excised hairless mice skin than GKH. in vivo study showed that TAT-GKH had a better effect upon the relative volume of eye bag after 28 days of application on twenty(+2) healthy female volunteers. It was identified that TAT-GKH increases penetration enhancement and lipolytic effects in both in vitro, ex vivo and in vivo.

• Journal of Industrial Technology
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• v.32 no.A
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• pp.65-70
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• 2012

Carboxy-guns are used for rapid and precise injection of $CO_2$ gas to the target skin area using external power source. In the design of carboxy-gun, the most important thing is how to precisely control injection volume of $CO_2$ gas. This paper deals with the control scheme of injection volume of carboxy-gun using solenoid valve. First the amount of volume that passes through the solenoid valve under on-off time ratio control is estimated based on the assumption of compressible gas flow. The flow rate of gas is experimentally measured under the varying pressure of the gas reservoir. Two results showed good correlation to each other, thus demonstrating the validity of the volume control strategy.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.269-273
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• 1999

Combination of mental stress task with noise background is a traditional tool employed in psychophysiology. However, intensity of background noise is a factor affecting both performance on test and psychophysiological responses associated with stress evoked by mental load in noisy environment. In the current study on 7 subjects we analyzed the influence of white noise (WN) intensity (55, 70, and 85 dB[A] ) on psychophysiological responses during word recognition test performed on noise background. There were recorded following physiological variables: electrodermal activity (EDA) , namely, skin conductance level (SCL), skin conductance response (SCR) amplitude (SCR-A), rise time and total number of SCRs (N-SCR); cardiovascular activity, e.g., heart rate (HR), respiratory sinus arrhythmia (RSA) index, pulse transit time (PTT), finger pulse volume (PV), skin temperature (SKT) and respiratory activity, such as respiration rate (RESP-R) and inspiration wane amplitude (RESP-A) during baseline resting state and 40 s long performance on 3 similar Korean word recognition tests with different WN intensity (55, 70, and 85 dB). Electrodermal responses (SCR-A, SCL, N-SCR) demonstrated gradual increment with increased intensity of noise, and this increase of response magnitude with higher intensity of noise was typical also for r skin temperature (phasic SKT decrease) and pulse volume (phasic and tonic PV decrease). However, some cardiovascular and respiratory responses did not exhibit same tendency of gradual increase of reactivity , namely HR, as well as RESP-R and RESP-A showed decrement of response magnitudes. Important finding in terms of cardiovascular reactivity was that 55 and 70dB evoked similar profiles, while 85dB WN resulted in significantly different profile of reactions, suggesting that there exists a threshold level after which intensive auditory stimulation elicits psychophyslological responses pattern of different quality. There are discussed potential autonomic mechanism involved in mediation of observed physiological responses.

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.2 s.24
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• pp.57-67
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• 1987

The purpose of this study was to confirm the effects of girdle on the physiological responses and the microclimate in summer. The measuring points were rectal temperature, skin temperature, pulse rate and sweat volume as physiological responses and the inside clothing temperature, relative humidity as microclimate when the subjects wore girdle (girdle A; polyurethan+nylon, girdle B; polyurethan+cotton) for the period of rest and exercise in climate chamber. The enviromental conditions were at $25^{\circ}C$ ($65{\pm}5\%$ RH) and $30^{\circ}C$ ($75{\pm}5\%$ RR). The results were as followings. 1. Mean skin temperature increased in girdle during the exercise at $30^{\circ}C$. 2. The pulse rate decreased in girdle during the rest at $25^{\circ}C$. In the case of girdle A, it was remarkably decreased. Rectal temperature increased in girdle A and B during the exercise at $25^{\circ}C$. But the kinds of girdle didn't affect the pulse rate and rectal temperature. 3. The total sweat volume in girdle was larger than in control. 4. The difference between skin temperature and inside clothing temperature of abdomen had a tendency to increase at all experiment condition. 5. The relative humidity of inside ($RH_1$) and outside ($RH_2$) of girdle increased in girdle during the rest at $25^{\circ}C$ and $30^{\circ}C$. And the relative humidity of wearing girdle B was hig-her than girdle A during the rest at $25^{\circ}C$ and $30^{\circ}C$. The $RH_1$ after stepping at $30^{\circ}C$ was the highest in girdle A and the lowest in control. From this point of view, we concluded that physiological responses and the microclimate were affected by wearing girdle. And mean skin temperature and relative humidity of inside clothing were affected by the materials of girdle.

• Archives of Craniofacial Surgery
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• v.22 no.2
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• pp.85-92
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• 2021

Background: Patients with secondary deformities associated with unilateral cleft lip and nose might also suffer from nostril stenosis due to a lack of tissue volume in the nostril on the cleft side. Here, we used full-thickness skin grafts (FTSGs) to reduce nostril stenosis and various methods for skin volume augmentation. We compared the changes in the symmetry of both nostrils before and after surgery. Methods: From February 2016 to January 2020, 34 patients underwent secondary cheiloplasty and open rhinoplasty for secondary deformities of the unilateral cleft lip and nose with nostril stenosis. FTSG was used on the nostril floor, nasal columella, and alar inner lining. The measured nasal profile included the nostril surface, nostril circumference, width of the nostril floor, and distance from the alar-facial groove to the nasal tip. The "overlap area," which was defined as the largest overlapping area when the image of the cleft nostril was flipped to the left and right and overlaid on the image of the normal side nostril, was also calculated. The degree of symmetry was evaluated by dividing the value of the cleft side by that of the normal side of each measured profile and expressed as "ratios." Results: The results of all profile ratios, except for the nostril floor width, became significantly close to 1, which represents full symmetry. The overlap area ratio improved from 62.7% to 77.3%, meaning that the length and width of the nostril as well as the overall shape became similar (p< 0.05). Conclusion: When performing cleft rhinoplasty with nostril stenosis, FTSG is useful to achieve symmetry in the nostril size and shape. Skin grafting is simpler to perform than the other types of local flap, and the results are generally satisfactory.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.4
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• pp.361-372
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• 2019

The flow pattern of air layers and skin-friction drag reduction by air injection are investigated to find the suitable multiphase flow model using unstructured finite-volume CFD solver for the Reynolds-averaged Navier-Stokes equations. In the present computations, two different multiphase flow modeling approaches, such as the Volume of Fluid (VOF) and the Eulerian Multi-Phase (EMP), are adopted to investigate their performances in resolving the two-phase flow pattern and in estimating the frictional drag reduction. First of all, the formation pattern of air layers generated by air injection through a circular opening on the bottom of a flat plate are investigated. These results are then compared with those of MMkiharju's experimental results. Subsequently, the quantitative ratios of skin-friction drag reduction including the behavior of air layers, within turbulent boundary layers in large scale and at high Reynolds number conditions, are investigated under the same conditions as the model test that has been conducted in the US Navy's William B. Morgan Large Cavitation Channel (LCC). From these results, it is found that both VOF and EMP models have similar capability and accuracy in capturing the topology of ventilated air cavities so called'air pockets and branches'. However, EMP model is more favorable in predicting quantitatively the percentage of frictional drag reduction by air injection.