• Journal of the Korean Society for Precision Engineering
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• v.19 no.4
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• pp.117-123
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• 2002

X-ray diffraction observation of fracture surfaces yields useful information to analyze the causes of failure accidents of engineering structures. This experimental technique, named X-ray fractography, has been developed especially in metal and mechanical engineering fields. The distributions of the residual stress and the half value breadth of diffraction profiles beneath the fatigue fracture surface were measured with SNCM 439, HT100 and Ti-6Al-4V alloy. The size of the maximum plastic zone was successfully determined on the basis of the measured distributions. This size was correlated to maximum stress intensity factor. The distributions of the half value breadth of diffraction profiles on the fatigue fracture surfaces were measured with SNCM 439. HT100. The equations of x-ray parameter distribution were possible to estimated fracture parameters of fatigue fracture surfaces.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.5
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• pp.930-942
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• 1996

This study was done to provide the characteristics of body surface changes at armhole area. Experiments were carried out at upper arm and upper body inchuding 67 items, 74 segments by the stanard posture and arm movements. The subjects were 15 females of twenty aged. The major conclusions of this study are; 1. On the circumference items of upper arm, armhole circumference was decreased by all arm movement, especially high contracted on front armhole line. The most contracted segments of armhole circumference were from the shonlder point to front and back interscye breadth point. Axillary circumference was increased 5 cm to the utmost, so the function of sleeve pattern would be decided by axillary circumference. 2. The lengths of upper arm were decreased near center line, sleeve cap length was contracted 3∼4 cm. Posterior armpit point area was increased both length and breadth. According to the rates of expansion and contraction, the diagram of expansion and contraction of upper arm was suggested. 3. On upper body, back side chest breadth was increased exceedingly and shoulder length was decreased most. It was apparent that surface changes of upper body were greatly larger as far away from center front and center back line. The rates of expansion and contraction of upper body were also represented as a diagram of surface changes.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.45-53
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• 2008

Feeding habits of Pseudoblennius percoides collected from the eelgrass bed in Dongdae Bay from January to December 2005 were studied. P. percoides was a carnivore which mainly consumed fishes and caridean shrimps. Its diets included small quantities of mysids,amphipods (gammarid amphipods and caprellid amphipods), copepods, cephalopods, polychaetes,and crabs. P. percoides undergoes significant size-related changes; smaller fish (<3.0 cm SL) prey mainly copepods, gammarid amphipods, and mysids while the proportion of caridean shrimps and fishes increases with fish size. Fishes and caridean shrimps were major prey organisms for all seasons. Dietary breadth of P. percoides was lower with fish size and seasons.

• Proceedings of the ESK Conference
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• 1996.04a
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• pp.201-211
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• 1996

This study was carried out on 132 obese women who satisfied both of the conditions for obesity : over 1.6 in Roher index and over 90cm in bust girth. The purpose of the study was to classify body shape of obese women and find out their respective characteristics. 1. The characteristics on shape of body measurements are the front of waist height was higer than the back of waist height due to the obesity in abdominal region and the front of the abodominal depthe was high indicating the protruding of the abdominal region. 2. Characteristics of different obese body types 1) In the study of total body type, 5 factors were found as a result of factor analsis and body types were classified 4 types (type 1: short upper torso and obese arms and legs, type 2: Long and thick torso, type 3: the most obese torso, arms and legs, type 4: less obese torso according to the cluster analysis. 2) The torso body types were coassified 2 groups (type 1: less obese than average body type, type 2: large in all girth, depth and breadth according) to the different body parts such as back lengh, bust girth, hip girth and acromion to acromion breadth. 3) The lower body types were classified 2 groups (type 1: short legs, less the depth and breadth, type 2: large in all lower body measurenents) according to back of waist height, waist girth and hip girth.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.764-767
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• 2005

This paper deals with the flexural-torsional free vibrations of circular strip foundations with a variable breadth. The breadth of strip foundation varies with the linear functional fashion, which is symmetric about the mid-arc. Differential equations governing free vibrations of such foundations are derived, in which Winkler foundation is considered as the model of elastic soils. Effects of the rotatory and torsional inertias and shear deformation are included in the governing equations. Differential equations are numerically solved to calculate the natural frequencies. In the numerical examples, the free-free end constraint is considered. Effects of the rotatory and torsional inertias and shear parameter on the natural frequencies are reported. Parametric studies between frequency parameters and various system parameters are investigated.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.6
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• pp.85-94
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• 2020

The importance of organizational learning is increasing. Drawing on regulatory focus theory and upper echelon theory, this study aims to identify the relationship of the regulatory focus of managers and three aspects of organizational learning, namely breadth, depth, and speed of organizational learning. While identifying the significant influence of promotion focus on the three aspects of organizational learning, we found that the influence of promotion focus of breadth of organizational learning is statistically stronger than that of prevention focus.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.219-235
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• 2012

Objective: The aim of this study is to analyze the change characteristics of boys among the ages of 13 and 18 years. This study is based on the $4^{th}$ to the $6^{th}$ national anthropometric survey(Size Korea) data. Background: Many changes can affect the body characteristics compared withthe past. The significant changes were shown in Pepsi generation according to the report of national anthropometric survey of Korea 1997. Method: The subjects of the survey were 1,899 boys of the $4^{th}$ Size Korea, 1,587 boys of the $5^{th}$Size Korea and 2,317 boys of the $6^{th}$ Size Korea, who were from 13 to 18 years old. The change characteristics were analyzed withanthropometric measurements, height index value and proportion. Results: Stature was increased in 17~18 years old age group of the $5^{th}$ and the $6^{th}$ Size Korea and height items of the lower body showed the tendency to increase as the $6^{th}$ Size Korea over the time. In the case of circumference items, the tendency to increase in the $5^{th}$ and the $6^{th}$ Size Korea was observed. If the $5^{th}$ and the $6^{th}$ Size Korea were compared, there were no changes of other circumference items but chest circumference of the $6^{th}$ Size Korea was decreased in comparison with the $5^{th}$ Size Korea. Waist breadth(natural indentation) was increased in the $6^{th}$ Size Korea in spite of chest breadth was decreased in the $5^{th}$ and the $6^{th}$ Size Korea. And shoulder length, biacromion length and bishoulder length were decreased. The proportion of chest circumference, abdominal extension circumference and hip circumference to waist circumference and the proportion of chest breadth to waist breadth(natural indentation) showed the tendency to decrease as the $6^{th}$ Size Korea over the time. Conclusion: There was no change of stature excluding 17~18 years old. Circumference items showed tendency to increase as the $6^{th}$ Size Korea over the time. Shoulder and chest breadth became narrow. The somatotype changed to board chest with narrow waist in comparison with the previous. Application: In this way, the body size of 13~18 years' old boys changes. If these change characteristics reflects to the school uniform design, research for the pattern development, and etc., these will be able to improve fit and satisfaction of clothes.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.429-439
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• 2013

This study was conducted to determine the changes of the ecological niche breadth and niche overlap of Quercus acutissima and Quercus variabilis under elevated $CO_2$ concentrations and under elevated temperature conditions. We investigated the growth responses by environmental factor, $CO_2$ concentration, air temperature, light, soil moisture and nutrients. Rising $CO_2$ concentration was treated with 1.6 times than control (ambient) and increased temperature with $2.2^{\circ}C$ above the control (ambient) in the glass greenhouse. Ecological niche breadth and niche overlap was calculated the two oak species (Q. acutissima and Q. variabilis), which were cultivated with light, soil moisture and nutrient gradients at four levels. As a result, the ecological niche breadth of Quercus acutissima was determined to be increased under the warming treatment, but decreased under soil moisture and nutrient environments. The ecological niche breadth of Quercus variabilis was increased under light, soil moisture and nutrients of the warming treatment than control. Ecological niche overlap between Quercus acutissima-Quercus variabilis was increased under light of the warming treatment than control, but decreased under soil moisture and nutrient environments. These results means that two oak species are more severe competition in light environments than soil moisture and nutrient environments. According to analyses of the Cluster and PCA, the two oak species were more sensitive react under light environment than to elevated $CO_2$ concentration or elevated temperature.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.102-108
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• 2020

This study is to analyze the growth response of the Quercus dentata seedlings to four environmental factors and measure the ecological niche breadth. Environmental factors were light, moisture content, soil texture, and organic matter, treated with four gradients. The more quantity light increased, the heavier the leaves biomass, aboveground biomass, belowground biomass and plant biomass was. In treatment of water content and soil texture, growth response was no difference. The more organic matter increased, the heavier aboveground biomass was, but the remaining trait of plant was no difference. The ecological niche breadth was 0.865 in light, 0.995 in moisture content, 0.994 in soil texture and 0.988 in nutrient. Ecological niche breadth was the widest in the moisture content treatment and the narrowest in the light treatment. This means that the growth of Q. dentata seedlings grows well as the amount of light increases, and is sensitive to light, Thus, it is determined a growth and ecological niche breadth by light factors.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.191-197
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• 2009

In order to characterize the ecological traits of Q. mongolica, we treated the seedlings of this species with three environmental factors, light, moisture and nutrient gradients from March to October 2007, and measured morphological and ecological 17 characters. Lastly calculated ecological niche breadth and niche overlap between Q. mongolica-Q. acutissima and Q. mongolica-Q. variabilis, and analysed them with a special reference to ecological distribution pattern and their competition relationship in Korea. The ecological niche breadth of Q. mongolica showed the lowest in nutrient treatment, but the highest in soil moisture treatment. The ecological niche value under light was intermediate. On comparison of the ecological niche breadth of three oak species, Q. mongolica showed the highest in light environment, which might be a reason for the dominant distribution in the forest plant community, Korea. The ecological niche overlap of Q. mongolica-Q. acutissima and Q. mongolica-Q. varabilis was the widest in moisture treatment, but the narrowest in nutrient treatment and the intermediate in light one. These results means that these three oak species be most competitive in moisture environment than light or nutrient one, and that there are least differentiated among oak species for soil moisture condition. Cluster and PCA ordination showed that Q. mongolica and Q. acutissima were more closely arranged than Q. mongolica and Q. variabilis. From these results, it can be explained that Q. mongolica have more similar ecological niche with Q. acutissima than with Q. variabilis, consequently competition between Q. mongolica and Q. acutissima is intensive than Q. mongolica and Q. variabilis for environment condition, especially in soil moisture.