• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.49.1-49
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• 2001

The skin color model is a very important concept in face detection, face recognition and face tracking. Usually, this model is obtained by estimating a probability density function of skin color distribution. In many cases, it is assumed that the underlying density function follows a Gaussian distribution. In this paper, a new method for non-parametric estimation of the probability density function, by using feed-forward neural network, is used to estimate the underlying skin color model. By using this method, the resulting skin color model is better than the Gaussian estimation and substantially approaches the real distribution. Applications to face detection and face ...

• Biomedical Science Letters
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• v.13 no.1
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• pp.55-60
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• 2007

Computerized image processing and analysis system was used for quantitative assessment of skin tissue components in color histological sections. The purpose of this study was to determine that the changes in the collagen fiber density and elastic fiber density in dermis in the rat skin as aging. And also to determine that the correlation between fibroblast density and collagen fiber density and elastic fiber density in the aged rat skin. Ten weeks old ($130{\sim}150g$) eight and fifty-four weeks old ($300{\sim}350g$) eight female Sprague-Dawley rats were used. The full-thickness skin biopsy specimens were prepared serial sections and stained with hematoxylin and eosin, Masson's trichrome and Verhoeff-van Gieson. The collagen fiber and the elastic fiber were identified using the image analysis processing system and then calculated the collagen fiber density rate and the elastic fiber density rate in the dermis. It also identified fibroblast and calculated fibroblast density in the dermis. By using a Student's t-test, a decrease in the collagen fiber density rate (t=-4.650, P<0.001) and the elastic fiber density rate (t=-6.494, P<0.001) of dermis can be observed in aged rats as compared with the young rats. A Student's t-test showed a significantly less fibroblast density in the aged rats than the young rats (t=-4.497, P<0.001). There were significantly positive correlation between the fibroblast density and the collagen fiber density rate (r=.69, P<0.001) and the elastic fiber density rate (r=.91, P<0.001). These results indicate that the aging may decrease the collagen fiber density and elastic fiber density due to reduced the proliferative and synthetic activity of fibroblast in the dermis.

• Journal of Pharmaceutical Investigation
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• v.35 no.2
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• pp.81-87
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• 2005

We have prepared karaya gum patches containing ketoprofen and investigated the effect of short-time current pretreatment of skin on the permeability. Hairless mouse skin was treated with current before the patch was mounted on the skin. The effect of current density and current duration on the flux of ketoprofen was studied. The possibility of additive effect with penetration enhancer (PGML) was also investigated. Iontophoretic pretreatment of skin increased the passive flux up to 3 folds at 0.4 $mA/cm^2$ current density, when the matrix contained no PGML. As the duration of current-pretreatment and current density increased, flux increased. PGML increased the average passive flux markedly, about 6 to 12 folds, depending on the concentration in the patch. Current pretreatment further increased the flux from this PGML containing patch, exhibiting additive effect. These results indicate that short-duration current pretreatment of skin can be an useful method for the enhancement of ketoprofen permeability through skin.

• Biomedical Science Letters
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• v.16 no.4
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• pp.349-357
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• 2010

We have examined the histological changes of skin during hair follicle growth after depilation in C57BL/6N mice. We first studied on histological changes of number of mast cells and thickness of skin during hair follicle growth periods (telogen, 1 day, 3 day, 5 day, 10 day, 14 day, 17 day and 21 day after depilation) by toluidine blue, Giemsa and H&E staining methods. We second studied immunoreactive density of cytokines and Brdu labeled cells in skin during hair follicle growth periods after depilation in C57BL/6N mice by immunohistochemical methods. The histological changes on skin thickness was increased from telogen to 14 day. The number of mast cells was decreased in 3,5 and 10 day and increased in 14, 17 and 20 day after depilation. Immunoreactive density of cytokines [protein kinase C-${\alpha}$ (PKC-${\alpha}$), c-kit, and vascular endothelial growth factor (VEGF)] in 1, 3, 5, 10, and 14 day after depilation was mildly stained in bulge and cutaneous trunci m., but immunoreactive density of cytokines in 17 and 21 day was heavily stained in epidermis, bulge, outer root sheath (ORS), inner root sheath (IRS) and cutaneous trunci m.. Immunoreactive density of Brdu labeled cells in skin in 1 and 3 day was heavily stained in bulge, epidermis and connective tissue under the cutaneous trunci m.. In all periods, immunoreactive density of Brdu labeled cells in skin was heavily stained in bulge, subcutaneous tissue, cutaneous trunci m, ORS and IRS. These experiments suggest that histological changes related to hair follicle growth elevated mast cell counts, skin thickness and epidermis thickness and heavily stained immunoreactive density of cytokines and Brdu labeled cutaneous trunci m. and connective tissue under the cutaneous trunci m. after depilation in C57BL/6N mice.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.2 s.57
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• pp.123-127
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• 2006

In this study, we evaluated the crow's fret of 95 Korean female by using mechanical assessments; Skin-Visiometer SV 600 and Dermascan C. Transparency profilometry (Skin Visiometer) were using a very thin skin print which allowed parallel light to pass through and was analysed immediately after production. High-frequency (20 MHz) ultrasonography (Dermascan C) enabled non-invasive evaluation in skin thickness and echodensity. We found a correlation between skin roughness and dermal density. Particularly, we showed a significant correlation between skin roughness (R2) and dermal thickness. Also, we demostrated a significant negative correlation between dermal density and dermal thickness (p < 0.05). Therefore, the ultrasonography system might be considered a very useful method in wrinkle evaluation with the transparency profilometry. Further study will be required.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.152-157
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• 2005

This experimental study was devoted to investigate skin friction of H group piles with uplift loading conditions in granite soil under laboratory test. Model piles made of steel embedded in weathered granite soil were used in this study. Pile arrangements($2{\times}2,\;3{\times}3$), pile space(2D, 4D, 6D), and soil density($D_r=40%,\;80%$) were tested. The main results obtained from the model tests can be summarized as follows. The series of tests found that ultimate uplift load and displacement for group piles were increased as piles space ratio increases to $D_r=40%$ of soil density. In the relative density of $D_r=80%$, bearing capacity for group piles was greater than for single pile. In the relative density of $D_r=40%$, the theoretical value of skin friction for group piles was greater than practical value. In the relative density of $D_r=80%$, both theoretical and practical value of skin friction for group piles were increased as piles space ratio increases.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.853-859
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• 1997

For asymmetric polyetherimide membranes having a dense layer gradient structure on the skin layer, the morphology change and pervaporation behaviors of water/isopropanol mixture through chemical modification of dense skin layer were investigated. The extent of the density was controlled by the evaporation, time, and when the evaporation time was increased from 0 min to 4 min, the permeation flux was decreased, the separation factor was increased. Also, the pervaporation behaviors of the polyetherimide membranes modified with sodium hydroxide solution, as the modification time of dense skin layer increased, the selectivity increased, and the permeation flux decreased. The morphology change identified by SEM shows that the density of dense skin layer tends to increase with increasing modification time, this result is consistent with above observations.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.971-972
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• 2008

In this paper, we present a novel method for classifying pornography images using adaptive skin detection. From an input image, we detect initial skin regions and construct an adaptive skin probability density model using color information for the detected skin regions. From the skin probability density model, we extract feature vectors and train the images using Support Vector Machine to classify pornography images.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.294.1-294.1
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• 2003

At pH 7.4 (physiological pH), skin is permselective to cations, due to the net negative charge of the current passing channels (pores) in skin. This causes the convective solvent flow (electroosmotic flow) from anode to cathodal direction. In this work, we have investigated several factors (pH. current density and ionic strength) that can affect the electroosmotic flow. (omitted)

• Korean Journal of Clinical Laboratory Science
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• v.40 no.2
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• pp.118-128
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• 2008

The aim of this study was to investigate the effect of electrical stimulation on healing of impaired wound and alteration of mast cells in experimental diabetic rats. Thirty male Sprague-Dawley rats were divided into three groups : incision (control), diabetes+incision (diabetes) and diabetes + incision + electrical stimulation (D/ES). Diabetes was induced in rats by streptozotocin (STZ) injection (60 mg/kg, one time) and 20 mm length incision wounds were created on the back after shaving hair. The electrical stimulation rats were treated with a current intensity of 30~50 V at 120 pps and $140{\mu}s$ for 10 days from 3 days after STZ injection. The lesion and adjacent skin tissues were fixed with 10% buffered formalin, embedded with paraffin. For wound healing analysis, hematoxylin-eosin (HE) and picrosirius red staining were performed. Mast cells (MC) were stained with toluidine blue (pH 0.5) and quantified at ${\times}200$ using a light microscope. The density of keratinocyte proliferation and microvessels in skin tissues were analyzed using a computerized image analysis system on sections immunostained with proliferative cell nuclear antigen (PCNA) and ${\alpha}$-smooth muscle actin (${\alpha}$-SMA), respectively. The results showed that the wound healing rate, collagen density and neoepidermis thickness, density of PCNA-positive cells and density of ${\alpha}$-SMA-positive vessels were significantly higher in D/ES rats than in diabetic rats. The density of MCs and degranulated MCs in D/ES rats were also significantly higher than those in diabetic rats. These findings suggest that the electrical stimulation may promote the tissue repair process by accelerating collagen production, keratinocyte proliferation and angiogenesis in the diabetic rats, and MCs are required for wound healing of skin in rats.