• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.188-198
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• 2018

Since infants' skin is very weak and has poor adaptability to environment, they are vulnerable to dermatitis caused by chemicals. Organic cotton for baby wear with the same functions in inner and outer wears can be considered the most suitable fiber. Therefore, this study analyzes products and colors of Korean and U.S. baby wear brands which use organic cotton. Of the total of seven organic brands of baby wear examined in this study, three were Korean baby wear brands and four were U.S. brands. and design colors of total 331 items were examined on the web. The results of comparative analysis showed that there were more U.S. brands than Korean brands in designs by uses. Color analysis showed that Korean natural cotton color was preferred and Y, G colors are commonly used, but colors of U.S. brands featured increased variety compared with Korean brands. Therefore, the Korean infant and toddler brand using organic cotton requires more diverse designs and delicate and broad colors.

• Physical Therapy Korea
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• v.8 no.3
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• pp.63-76
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• 2001

Many studies have shown that the initial median frequency (MDF) and slope correlate with the muscle fiber composition. This study tested the hypothesis that the initial MDF and slope are fixed, regardless of the interval at which data are collected. MDF data using moving fast Fourier transformation of EMG signals, following local fatigue induced by isotonic exercise, were obtained. An inverse FFT was used to eliminate noise, and characteristic decreasing regression lines were obtained. The regression analysis was done in three different periods, the first one third, first half, and full period, looking at variance in the initial MDF, slope, and fatigue index. Data from surface EMG signals during fatiguing isotonic exercise of the biceps brachii and vastus lateralis in 20 normal subjects were collected. The loads tested were 30% and 60% maximum voluntary contraction (MVC) in the biceps brachii and 40% and 80% MVC in the vastus lateralis. The rate was 25 flexions per minute. There were no significant differences in the initial MDF or slope during the early or full periods of the regression, but there was a significant difference in the fatigue index. Therefore, to observe the change in the initial MDF and slope of the MDF regression line during isotonic exercise, this study suggest that only the early interval need to be observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.10
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• pp.3199-3210
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• 1996

The buckling and postbuckling behaviors were sutdied analytically and experimentally for stiffened laminated composite panels under compression loading. The panels with I-, blade, -and hat-shapeed stiffeners were investigated. In the analysis, the stiffened panels were anlyzed using the nonlinear finite element method combined with an improved arc-length method. The progressive failure analysis was done by adopting the maximum stress criterion and complete unloading failure model. The effects of the fiber angles were investigated on the buckling and postbuckling behaviors. In the experiment, the web and the lower cap of each stiffener were formed by the continuous lay-up of the skin for cocuring the stiffened panels. Therefore, the separation between stiffener and skin was not found in the junction part even after postbuckling ultimate load and the stiffened panels had excellent postbuckling load carrying capacity. A shadow moire thchnique was used to monitor the out-of-plane deformations of the panels. The piezoelectric films were attached to the panels to get the failure characteristics of the panel. The analytical results on the buckling load, postbuckling ultimate load, and failure pattern showed good agreement with the experimental results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.2
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• pp.38-46
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• 2020

The purpose is to evaluate the structural characteristics of 750 mm diameter injection spiral blades under various operating conditions. A fiber-glass reinforced polypropylene material was employed to the injection blades, and mechanical tests on two kinds of glass-reinforced polypropylene were performed to evaluate the mechanical properties and to select a suitable candidate material. Also, three kinds of spiral blade geometries were studied to observe the influence of fixing rods between blades. For this, structural analyses were conducted to understand the role of fixing rods under a range of rotating speed. In addition, modal analysis was performed to confirm the resonance in the operating speed range. One-way fluid-structure interaction (FSI) analysis was carried out to know its mechanical integrity under dangerous wind speed conditions. Through this work, the structural characteristics of the proposed spiral blade geometries were studied under various operating conditions, and the requirements of mechanical properties of blades were determined.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.4
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• pp.227-236
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• 1997

Quantitative analysis and imaging of elastic wave propagation are very important for the materials evaluation as well as flaw detection. The elastic wave propagation in an anisotropic media is more complex, and analysis and imaging become essential for flaw detection and materials evaluation. In the anisotropic media, the wave velocity is dependent on the propagation direction. In addition, the direction of group velocity is different from that of phase velocity, the direction of energy flow is not same as the propagation direction of wavefront (beam skewing effect). Especially, this effect becomes critical for the large anisotropic media such as fiber composite materials, and the results using elastic waves for those materials have to be analyzed considering the wave propagation mechanism. Since the analytical approach for the wave propagation in the anisotropic materials is limited, the numerical analysis such as finite difference method (FDM) have been used for these case. Therefore, 2-dimensional FDM program for the elastic wave propagation is developed, and wave propagation in anisotropic media are simulated.

• Smart Structures and Systems
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• v.20 no.2
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• pp.139-150
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• 2017

The structural strain plays a significant role in structural condition assessment of in-service bridges in terms of structural bearing capacity, structural reliability level and entire safety redundancy. Therefore, it has been one of the most important parameters concerned by researchers and engineers engaged in structural health monitoring (SHM) practices. In this paper, an SHM system instrumented on the Jiubao Bridge located in Hangzhou, China is firstly introduced. This system involves nine subsystems and has been continuously operated for five years since 2012. As part of the SHM system, a total of 166 fiber Bragg grating (FBG) strain sensors are installed on the bridge to measure the dynamic strain responses of key structural components. Based on the strain monitoring data acquired in recent two years, the strain-based structural condition assessment of the Jiubao Bridge is carried out. The wavelet multi-resolution algorithm is applied to separate the temperature effect from the raw strain data. The obtained strain data under the normal traffic and wind condition and under the typhoon condition are examined for structural safety evaluation. The structural condition rating of the bridge in accordance with the AASHTO specification for condition evaluation and load and resistance factor rating of highway bridges is performed by use of the processed strain data in combination with finite element analysis. The analysis framework presented in this study can be used as a reference for facilitating the assessment, inspection and maintenance activities of in-service bridges instrumented with long-term SHM system.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.9-18
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• 2017

As an indicator of skin health, acidified skin surface pH ranging from 5 to 7 is crucial for maintaining skin barrier. In this study, we evaluated the relationship between skin pH and dietary pattern (DP) as well as nutrient or food intake in 48 healthy middle aged adults. Skin pH was measured in the skin surface of the inner arm, and blood lipid profile was analyzed. Dietary intake data were obtained using 1 day 24 hour recall method, and DP was extracted using factor analysis. Results revealed that skin pH ranged from 5.15 to 6.88 in all subjects. There was no significant difference in skin pH between males and females. When subjects were grouped by tertile of skin pH, the food intake of fruit, and the nutrient intake of omega 6 fatty acid, potassium, vitamin A, vitamin C, ${\beta}$-carotene, and riboflavin in the first tertile group with skin pH ranging from 5.15 to 5.68 were significantly higher than in the third tertile group with skin pH ranging from 6.26 to 6.88. There was no difference in blood lipid profile between the first and the third tertile group. Among 5 DP extracted by factor analysis, DP5 characterized by a high intake of nuts and fruits as well as a low intake of beverages and alcohol was inversely correlated with skin pH after adjusting for gender and age. DP5 was positively correlated with nutrient intake of carbohydrate, fiber, potassium, iron, vitamin A, vitamin C, ${\beta}$-carotene, thiamine, and riboflavin but negatively correlated with sodium after adjusting for gender, age, smoking, and energy intake. Therefore, acidified skin pH could be maintained by these DP and nutrients.

• Advances in Computational Design
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• v.5 no.2
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• pp.195-207
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• 2020

The present study focuses on the application of artificial neural network (ANN) and Multiple linear Regression (MLR) analysis for developing a model to predict the unconfined compressive strength (UCS) and split tensile strength (STS) of the fiber reinforced clay stabilized with grass ash, fly ash and lime. Unconfined compressive strength and Split tensile strength are the nonlinear functions and becomes difficult for developing a predicting model. Artificial neural networks are the efficient tools for predicting models possessing non linearity and are used in the present study along with regression analysis for predicting both UCS and STS. The data required for the model was obtained by systematic experiments performed on only Kaolin clay, clay mixed with varying percentages of fly ash, grass ash, polypropylene fibers and lime as between 10-20%, 1-4%, 0-1.5% and 0-8% respectively. Further, the optimum values of the various stabilizing materials were determined from the experiments. The effect of stabilization is observed by performing compaction tests, split tensile tests and unconfined compression tests. ANN models are trained using the inputs and targets obtained from the experiments. Performance of ANN and Regression analysis is checked with statistical error of correlation coefficient (R) and both the methods predict the UCS and STS values quite well; but it is observed that ANN can predict both the values of UCS as well as STS simultaneously whereas MLR predicts the values separately. It is also observed that only STS values can be predicted efficiently by MLR.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.455-462
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• 2013

NLR family pyrin domain containing 3 (NLRP3) is a key component of the inflammasome, whose assembly is a crucial part of the innate immune response. The aim of the present study was to evaluate the association between exon 3 polymorphisms of NLRP3 and the susceptibility to digestive disorders in rabbits. In total, five coding single-nucleotide polymorphisms (cSNPs) were identified; all of which are synonymous. Among them, c.456 C> and c.594 G> were further genotyped for association analysis based on case-control design (n =162 vs n =102). Meanwhile, growing rabbits were experimentally induced to digestive disorders by feeding a fiber-deficient diet, subsequently they were subjected to mRNA expression analysis. Association analysis revealed that haplotype H1 (the two cSNPs: GT) played a potential protective role against digestive disorders (p<0.001). The expression of NLRP3 in the group $H1HX_1$ ($H1HX_1$ is composed of H1H1, H1H3 and H1H4) was the lowest among four groups which were classified by different types of diplotypes. Those results suggested that the NLRP3 gene was significantly associated with susceptibility to digestive disorders in rabbit.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.225-232
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• 2013

Omija component was known to possess natural odor, taste, color, and various general characteristics. Omija extraction was extracted using ethanol as a solvent. Omija extract showed a red-purple color of some viscous liquid state. Some conclusions from natural Omija extract were obtained as follow. The result of antimicrobial experiment to add Omija extract, the number of microbial population showed negative reaction from 3 days after it cultivated. This phenomenon could confirm that Omija component affected to antimicrobial effect. The result of dyeing experiment to add Omija extract, fiber dyeing effect showed with some ivory color after dyed to cotton and silk. Also, this phenomenon could confirm that Omija component affected to natural dyeing effect from observated dye state with biological microscope(BM). The result of instrumental analysis, inorganic components of K(109.60ppm), Na(3.500ppm), Ca(1.205ppm), Mg(0.900ppm), Li(0.350ppm), Si(0.380ppm), Cu(0.250ppm), Fe(0.125ppm), Zn(0.090ppm), etcs from Omija were ascertained with ICP/OES, and organic components of benzene(10.808), borny lacetate(11.289), phenol(14.183), ${\beta}$-terpinene(15.840), ${\alpha}$-terpinolene(17.616) etcs from Omija were ascertained with GC/MSD.