• Journal of Advanced Marine Engineering and Technology
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• v.26 no.1
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• pp.76-82
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• 2002

In this study, the rotary bending fatigue test was carried out with low carbon steel(SM25C). The specimens were heat-treated in order to change the grain size, and investigated items are fatigue limit, small crack initiation, fatigue crack propagation behavior and possibility of fatigue life prediction according to the different grain size. The summarized result are as follows ; Fatigue limit of the smooth specimen was dependent upon the grain size. The fatigue crack initiation of the small grain size specimen was delayed more than that of the large grain size specimen. And the small cracks of small grain size specimen were distributed in the narrow region of the main crack circumference contrary to the large grain size specimen. The main crack was grown along the grain boundary having co-alliance with small cracks. The experiment material has quantitatively disclosed the possibility of fatigue life prediction because the fatigue crack propagation behavior is dependent upon the grain size.

• Journal of the Korean Society of Costume
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• v.54 no.6
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• pp.77-90
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• 2004

The purpose of this study was to provide basic information requisite in the new sizing system for gloves. KS glove standards' size dimensions, size designation and labeling systems were analyzed. Also, KS glove standards' control sizes were compared to the anthropometric data of 824 Korean adults taken in the previous study. As well, the ISO hand size system was also compared to the anthropometric data of the previous study according to frequency tables of hand length and hand circumference. The size dimensions showed differences among KS standards and there was no size designation and labeling systems existed in KS standards. Among KS glove size systems, protective rubber gloves for radioactive contamination and surgical rubber gloves' size which followed ISO system were accurately indicate the hand size of the person a glove is intended to fit. ISO glove sizing system comprised the control dimensions of hand length and hand circumference. The coverage of ISO size A was 84.8% which was highest among ISO size A. B, C. And in hand circumference 178, 191, 203, 216mm showed the frequencies above 3% and in hand length 167, 175. 183, 191, 199mm showed the frequencies above 3%.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.817-825
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• 2020

Over the last few decades, corporate frauds have highlighted the significance of corporate governance in deriving firm performance. By using different sample data, extensive research has examined how corporate governance structure influences firm's profitability, but limited research was undertaken on the banking sector of Pakistan. This research adds to the literature by testing how board structure derives bank's performance by using sample data of 19 banks for the period from 2010 to 2017. In addition, the study analyzes the controlling part of size on the link between board governance and bank performance. Findings reveal that banks having small board size, fewer non-executive directors and minimum activity level perform better. Analysis related to bank size illustrates that board size has value in increasing benefits in large size banks in contrast to small size one, while higher participation by board members enhances performance of small size banks more. The correlation results and findings showed that there existed no multicollinearity issue between independent variables. Board size showed positive correlation with the market variable, while board activity tended to correlated negatively with the market performance. Inverse correlation between board size and independent directors indicated that Pakistani banks with greater board size had fewer independent directors.

• The Research Journal of the Costume Culture
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• v.23 no.1
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• pp.24-31
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• 2015

The purpose of this study was to define Korean adolescent girls' brassiere size demand features in order to improve the suitability of junior brassieres for adolescent girls. The subjects for the data collection were Korean teenage girls from age 13 to 17 (n=492). Their body size was collected by conducting anthropometric measurement. The results of this study show that not only the growth of height, but also the growth of the body length is almost finished at the age of 15. The brassiere cup size, which shows the breast growth directly, increased remarkably at age 13 to 14, and once again at age 17. The demand for brassiere band size 70 appeared generally high among all ages. The research also suggests that the band size 60 and over 85 is also needed among the teenage girls. In matters of the brassiere cup size, junior brassieres over B-cup size are also necessary for teenage girls with big breasts to support their heavy breast weight. These results imply that the junior brassiere companies should improve their brassiere size range to fit the teenage girls' breasts properly.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.7
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• pp.1148-1156
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• 2007

This study were examined Chinese size system and fitness for women's suits of Korean brands produced by the manufacturers operating in China. The results are as follows. 1. One manufacturer used Chinese size system for women's suits among those manufacturers in China. And the rests individually adopted different size system of various ways. 2. Chinese women almost satisfied fitness and size system for suits of Korean brand. Especially, they satisfied fitness and size system for jacket more than the other apparel items. Pants was the worst item of fitness satisfaction. 3. Size assortment of each items was very different for each manufacturers which extended their business in China. And the smallest size was more produced than the other size in many manufacturers. 4. Most of the women's suits manufacturers of Korean brand in China, were collected consumers' informations for fitness and size satisfaction through their salespersons. Most of them replied that they were repairing items which were not in good fitness.

• Advances in nano research
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• v.14 no.2
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• pp.155-164
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• 2023

Grain size in sheet metals in one of the main parameters in determining formability. Grain size control in industry requires delicate process control and equipment. In the present study, effects of grain size on the formability of steel sheets is investigated. Experimental investigation of effect of grain size is a cumbersome method which due to existence of many other effective parameters are not conclusive in some cases. On the other hand, since the average grain size of a crystalline material is a statistical parameter, using traditional methods are not sufficient for find the optimum grain size to maximize formability. Therefore, design of experiment (DoE) and artificial intelligence (AI) methods are coupled together in this study to find the optimum conditions for formability in terms of grain size and to predict forming limits of sheet metals under bi-stretch loading conditions. In this regard, a set of experiment is conducted to provide initial data for training and testing DoE and AI. Afterwards, the using response surface method (RSM) optimum grain size is calculated. Moreover, trained neural network is used to predict formability in the calculated optimum condition and the results compared to the experimental results. The findings of the present study show that DoE and AI could be a great aid in the design, determination and prediction of optimum grain size for maximizing sheet formability.

• Journal of Environmental Science International
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• v.21 no.4
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• pp.535-543
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• 2012

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan site, which is known as background area in Korea, from January to September 2011. The temporal variation and the size distribution of aerosol number concentration have been investigated. The entire averaged aerosol number concentration in the size range 0.25~32.0 ${\mu}m$ is about 252 particles/$cm^3$. The number concentration in small size ranges(${\leq}0.5{\mu}m$) are very higher than those in large size ranges, such as, the number concentration in range of larger than 6.5 ${\mu}m$ are almost zero particles/$cm^3$. The contributions of the number concentration to PM10 and/or PM2.5 are about 34%, 20.1% and 20.4% in the size range 0.25~0.28 ${\mu}m$, 0.28~0.30 ${\mu}m$ and 0.30~0.35 ${\mu}m$, respectively, however, the contributions are below 1% in range of larger than 0.58 ${\mu}m$. The monthly variations in the number concentration in smaller size range(<1.0 ${\mu}m$) are evidently different from the variations in range of larger than 1.0 ${\mu}m$, but the variations are appeared similar patterns in smaller size range(<1.0 ${\mu}m$), also the variations in range of larger than 1.0 ${\mu}m$ are similar too. The diurnal variations in the number concentration for smaller particle(<1.0 ${\mu}m$) are not much, but the variations for larger particle are very evident. Size-fractioned aerosol number concentrations are dramatically decreased with increased particle size. The monthly differences in the size-fractioned number concentrations for smaller size range(<0.7 ${\mu}m$) are not observed, however, the remarkable monthly differences are observed for larger size than 0.7 ${\mu}m$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.7-12
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• 1997

This study was intended to investigate the proper shape and size of calcium carbonate for the improvement of paper properties and its end use performance. We loaded calcium carbonate of various shapes and size in the handsheet and measured their physical and optical properties. Results obtained from the study are summarized as follows : 1. Due to different particle shapes and sizes, precipitated calcium carbonate (PCC) contributed greater to bulk improvement than ground calcium carbonate (GCC). Scalenohedral form of PCC produced the bulkiest sheet, GCC made the sheet bulkier as average particle size increases. 2. Tensile strength increased as average particle size was increasing. GCC kept tensile strength more effectively than PCC. The effect of particle size on tensile strength was much more pronounced as filler addition level was increasing. 3. Over the average particle size of 6.99$\mu$m, GCC gave much higher burst strength and internal bond than PCC did. In the filler levels of 20% and 30%, GCC by using bigger size fillers showed 50~100% improvement in some cases than PCC at the same filler content. 4. Tear strength increased as average particle size was increasing. At the filler level of 30%, PCC decreased tear greatly. 5. Over the average particle size of 13.56$\mu$m, GCC kept bending stiffness greater than PCC. Due to its shape, Scalenohedral form of PCC showed higher stiffness than others at the same particle size. 6. Cubic and acicular form of PCC improved light scattering coefficient very effectively. Light scattering coefficient of GCC decreased as average particle size increased. 7. Both of particle shape and size of filler were important factor in developing optical properties and bending stiffness. Particle size was the only important factor in developing other strength properties

• The Research Journal of the Costume Culture
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• v.26 no.3
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• pp.313-326
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• 2018

Over the past few years, companies have started moving into specific niches in plus-size fashion. The purpose of this study was to verify the marketability of young plus-size clothes in the USA. Data were collected from female consumers aged from 20 to 39 who have experience of purchasing plus-size items. A total of 282 responses were used for statistical analysis. The research result is as follows. First, the obesity stress is affected more by the subjective obesity level than by the objective obesity level and by how people recognize their body types. Second, from an analysis of the factors affecting the shopping orientation of plus-size consumers, style consciousness, pursuing reasonable, emphasizing comfort, and body consciousness are found to be important factors. Third, even if responders are aware of their exact body size, they actively look for the correct size. Fourth, fit evaluation of plus-size products is based on the factors of size fit and movement fit. The respondents were unsatisfied with chest and arm measurements, which deviate widely by body type for tops. Fifth, the overall dissatisfaction with the plus-size market is attributed to the fact that the product assortment range from which to select styles is narrow, and trend reflection is low. Sixth, the respondents tended to avoid fabrics that make their body type more obvious, textures that give the impression of a larger body size, or stiff textures. These results show that the psychological and physical characteristics of obese consumers should be considered to develop products for the young plus-size market.

• Computers and Concrete
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• v.28 no.5
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• pp.521-532
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• 2021

Present paper focuses on the modeling of size effect on the compressive strength of normal concrete with the application of Discrete Element Method (DEM). Test specimens with different size and shape were cast and uniaxial compressive strength test was performed on each sample. Five different concrete mixes were used, all belonging to a different normal strength concrete class (C20/25, C30/37, C35/45, C45/55, and C50/60). The numerical simulations were carried out by using the PFC 5 software, which applies rigid spheres and contacts between them to model the material. DEM modeling of size effect could be advantageous because the development of micro-cracks in the material can be observed and the failure mode can be visualized. The series of experiments were repeated with the model after calibration. The relationship of the parallel bond strength of the contacts and the laboratory compressive strength test was analyzed by aiming to determine a relation between the compressive strength and the bond strength of different sized models. An equation was derived based on Bazant's size effect law to estimate the parallel bond strength of differently sized specimens. The parameters of the equation were optimized based on measurement data using nonlinear least-squares method with SSE (sum of squared errors) objective function. The laboratory test results showed a good agreement with the literature data (compressive strength is decreasing with the increase of the size of the specimen regardless of the shape). The derived estimation models showed strong correlation with the measurement data. The results indicated that the size effect is stronger on concretes with lower strength class due to the higher level of inhomogeneity of the material. It was observed that size effect is more significant on cube specimens than on cylinder samples, which can be caused by the side ratios of the specimens and the size of the purely compressed zone. A limit value for the minimum size of DE model for cubes and cylinder was determined, above which the size effect on compressive strength can be neglected within the investigated size range. The relationship of model size (particle number) and computational time was analyzed and a method to decrease the computational time (number of iterations) of material genesis is proposed.