• 한국생산제조학회지
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• 제6권1호
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• pp.45-50
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• 1997

It is not clearly known how surface defects or inclusions of a medium carbon steel affect a fatigue strength. In this study, we used SM35C specimens with spheroidized cementite structure to eliminate dependence of micro structure of fatigue crack. The investigation was carried out by behavior of crack closure at non-propagation crack and effect of the fatigue limit according to the artificial defects size. Experimental findings are obtained as follows : (1) Fatigue crack initiation point of medium carbon steel with spheroidized cementite structure is at the surface defects. (2) Non-propagating crack length of smooth specimen is equal to the critical size of defect. (3) Considering the opening and closure behavior of fatigue crack, the defect shape results in various crack opening displacement, while it does not affects the fatigue limit level of medium carbon steel with spheroidized cementite structure. (4) The critical length of the non-propagation crack of smooth specimen is the same as critical size of defect in transient area which determines threshold condition in steel with spheroidized cementite structure.

• 무역상무연구
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• 제49권
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• pp.379-405
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• 2011

With the fast growing of international trade and ever-changing trade environment Korea is facing more risks in international trade and they are getting more diverse and happen more frequent with high severity. Big firms of international trade are ready and treat the risks quite well, but small and medium size firms have hard time to manage the risks due to their poor understanding, not much capital to spend, and weak skills of risk management. Holding significant size of international trade of Korea, the small and medium size firms need systematic and integrated risk management and the K-sure(former Korea Export Insurance) can make a significant contribution to help them manage risks in international trade business. This study is proposing the adoption of ERM(Enterprise Risk Management) for international trade business of Korea. Especially for small and medium size firms of international trade, the K-sure may set up integrated risk management system to help them and promote the export growth, which is a great mission of K-sure.

• International Journal of Concrete Structures and Materials
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• 제5권1호
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• pp.49-55
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• 2011

The main objective of this investigation is to study size effect on compressive strength of CFRP confined concrete cylinders subjected to axial compressive loading. In total 24 concrete cylinders with different sizes were tested, small specimens with a diameter of 100 mm and a height of 200 mm, medium specimens with a diameter of 200 mm and a height of 400 mm, and big specimens with a diameter of 300 mm and a height of 600 mm. The lateral confining pressure of each specimen is the same and from that hypothesis the small specimens were confined with one layer of CFRP, medium and big specimens were performed by two and three layers of CFRP respectively. Test results indicate a significant enhancement in compressive strength for all confined specimens, and moreover, the compressive strengths of small and medium specimens are almost the same while a bit lower for big specimens. These results permit to conclude that there is no size effect on compressive strength of confined specimens regardless of cylinder dimension.

• Asian-Australasian Journal of Animal Sciences
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• 제20권11호
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• pp.1738-1745
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• 2007

A growth trial and a digestibility trial were conducted to examine the effect of feed particle size on the performance, nutrient digestibility, gastric ulceration and intestinal morphology in pigs fed barley-based diets. Barley was processed through a hammer mill to achieve four diets varying in particle size (average particle $size{\pm}standard $deviation): coarse ($1,100{\pm}2.19\;{\mu}m$), medium ($785{\pm}2.23\;{\mu}m$), fine ($434{\pm}1.70\;{\mu}m$) and mixed (1/3 of coarse, medium and fine) ($789{\pm}2.45\;{\mu}m$). Sixty-four entire male pigs were used in the growth trial and the diets were fed ad libitum between 31 kg and 87 kg live weight. Following slaughter, stomach and ileal tissues were scored for integrity (ulceration or damage) and histological measurements taken. Twenty-four entire male pigs were used in the digestibility trial, which involved total faecal collection. Over the entire growth phase, there were no differences (p>0.05) in average daily gain and feed conversion ratio between pigs fed diets of different particle size. Pigs fed the coarse and medium diets had lower (p<0.05) stomach ulceration scores (0.20 and 0.25, respectively, on a scale from 0 to 3) than those fed the mixed (0.69) or the fine diets (1.87). The stomachs of all animals fed the fine diet had lesions and stomach ulcerations were present only in this group. Pigs fed the fine diet had thicker (p<0.001) ileal epithelial cell layer with no differences (p>0.05) being observed for villous height or crypt depth. Faecal digestibility coefficients of neutral and acid detergent fibre were the highest (p<0.05) for the mixed diet, intermediate for the fine and coarse diets and the lowest for the medium diet. A similar numerical trend (p = 0.103) was observed for the apparent faecal energy digestibility coefficient. It is concluded that, with barley based diets, a variation in average particle size between $400{\mu}m$ and $1,100{\mu}m$ had no effect on pig performance but the fine dietary particle size affected the integrity of the stomach, as well as the structure of the small intestine, thus compromising overall gut health. Our data also demonstrate that changes in particle size distribution during the digestion process, rather than average particle size or particle size variation, are related to apparent faecal digestibility.

• 농업과학연구
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• 제13권1호
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• pp.1-16
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• 1986

새로운 유전(遺傳) 육종적(育種的) 재료(材料)를 얻고 탐색(探索)하기 위하여 수집(蒐集)한 재래종(在來種) 옥수수 262계통(系統)의 형태적(形態的) 특성분류(特性分類) 및 그 특성(特性)의 분포(分布), 상관(相關)둥을 요약(要約)하면 다음과 같다. 1. 각(各) 특성(特性)을 살펴 보면 개화소요일수(開花所要日數)에서 66일(日) 이하(以下)가 47%, 67~78일(日) 47%, 79일(日) 이상(以上)이 8%로 조(早) 중생(中生)에 고루 분포(分布)하였고 기타(其他) 특성(特性)들은 평균식(平均植)를 중심(中心)으로 양편에 고루 분포(分布)하였다. 2. 분얼수(分蘖數)는 변이계수(變異係數)가 49.2%로 특성(特性)들 중(中)에서 가장 큰 변이(變異)를 보였고 자수경(雌穗俓) 립중(粒重), 100립중(粒重), 착수고(着穗高), 초장(草長), 자수장(雌穗長) 등에서 각각(各各) 36.1, 27.2, 20.0, 16.3% 등으로 비교적 변이(變異)의 폭(幅)이 컸고 자수경(雌穗經), 입(粒)의 장(長), 폭(幅), 후(厚) 및 자수열수(雌穗列數), 개화소요일수(開化所要日數) 등에서 작은 변이(變異)를 보였다. 3. 특성(特性)들간에는 초장(草長)과 착수고(着穗高), 자수장(雌穗長), 자수경(雌穗俓), 분얼수(分蘖數), 개화소요일수(開花所要日數)와 높은 정(正)의 상관(相關)을 보였고, 100 립중(粒重), 자수당립(雌穗當粒)은 립(粒)의 장(長), 폭(幅), 후(厚) 및 초장(草長)과 높은 정(正)의 상관(相關)을 보였다. 4. 계통간(系統間)의 Euclidean distance에 의해 분류(分類)한 4개(個)의 군(群)은 I군(群)에 110개(個), II군(群)에 74개(個), III군(群)에 66개(個), IV군(群)에 12개(個) 계통(系統)이 속(屬)하였으며, 계통군(系統群) I은 조생(早生), 중간(中稈), 대립(大粒), 대형자수(大型雌穗)의 특징(特徵)을 계통군(系統群)II는 중생(中生), 중간(中稈), 중립(中粒), 소형자수(小型雌穗)의 특징(特徵)을, 계통군(系統群)III은 중생(中生), 중간(中稈), 대립(大粒), 중형자수(中型雌穗)의 특징(特徵)을 계통군(系統群)IV는 만생(晩生), 장간(長稈), 소형자수(小型雌穗), 소립(小粒), 다분얼(多分蘖)의 특징(特徵)을 각각(各各) 보였다. 5. 분류(分類)한 군별(群別) 평균초장(平均草長)은 I 군(群)과 II 군(群), II군(群)과 III, IV군(群) 사이에 유의차(有意差)가 인정(認定)되었고, 이삭의 크기에서는 IV군(群)과 II군(群), IV군(群)과 III군(群) 사이를 제외(除外)한 모든 군(群)사이에, 립(粒)의 크기는 II군(群)과 IV군(群) 사이를 제외한 모든 군(群)사이에 100 립중(粒重), 이삭당립중(當粒重)은 모든 군간(群間)에, 이삭열수(列數)는 I군(群)과 II군(群), IV군(群)과 I, II, III군(群) 사이에, 분얼수(分蘖數)와 개화일수(開花日數)는 IV군(群)과 I, II, II군(群) 사이에 각각(各各)그 유의차(有意差)가 인정(認定)되었다. 6. 강원도(江原道)와 제주도(濟州道)를 제외(除外)한 지역(地域)에서 수집(蒐集)한 옥수수를 지역별(地域別)로 나누었을 때 북서부평야지(北西部平野地)와 중부산악지(中部山岳地)의 옥수수는 중생(中生), 중간(中稈), 대형자수(大型雌穗), 대립(大粒)의 특징(特徵)을 중동부산악지(中東部山岳地)의 옥수수는 중생(中生), 중간(中稈), 중형자수(中型雌穗), 중립(中粒)의 특징(特徵)을 중서부평야지(中西部平野地)의 것은 중생(中生), 단간(短稈), 중형자수(中型雌穗), 중립(中粒)의 특징(特徵)을 남동부평야지(南東部平野地)의 것은 조생(早生), 단간(短稈), 소형자수(小型雌穗), 중립(中粒)의 특징(特徵)을 중남부산악지(中南部山岳地)의 것은 만생(晩生), 중간(中稈), 중형자수(中型雌穗), 소립(小粒), 다분얼(多分蘖)의 특징(特徵)을 남서부평야지(南西部平野地)의 것은 만생(晩生), 장간(長稈), 중형자수(中型雌穗), 소립(小粒), 다분얼(多分蘖)의 특징(特徵)을 나타내는 경향(傾向)을 보였다.

• 한국의류학회지
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• 제24권4호
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• pp.521-529
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• 2000

This paper proposed the sizing system for women's upper clothes in order to improve clothing fitness and raise the productivity. The sizing system was classified according to 5 body types and 5 age groups. The size intervals of the basic dimensions were established at regular intervals centering around their means. The size interval of stature was 8cm centering around 158cm and that of bust girth 4cm centering around 84cm and that of hip girth 4cm centering around 92cm. Frequency distribution on the size of upper clothes showed that the most frequent size were 96-96-150 in the longest-fattest type, 88-96-158 in the long-fatter type, 84-92-158 in the medium length-fat type, 84-92-166 in the Short-balanced type, and 76-88-158 and 80-88-158 in the medium length-balanced type. The number of the sizes of upper clothes, which had frequencies more than 5%, was 32 and each size was presented with waist girth, back waist length and sleeve length. The size system classified by age group had 22 cases in the early twenties, 15 cases in the late twenties, 21 cases in the early thirties, 19 cases in the late thirties, and 15 cases in the forties.

• 펄프종이기술
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• 제47권4호
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• pp.76-80
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• 2015

In filler loaded paper, the size of the filler affects its strength, optical and surface properties. As the size of the filler increases, tensile strength and bulk usually increases, opacity decreases, and smoothness becomes worse. Pre-flocculation of GCC (grounded calcium carbonate) makes large diameter flocs at aqueous medium that consists of multiple GCC particles, but they collapse to 2-dimensional shape in dried paper and makes low bulk paper. The hybrid calcium carbonate (HCC) that was made by in-situ $CaCO_3$ formation between GCC in aqueous medium made high bulk paper without harming tensile strength, bulk, opacity, and smoothness. The GCC that has equivalent size as HCC failed to make high opacity and smoothness as much as HCC.

• 벤처창업연구
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• 제1권1호
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• pp.105-125
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• 2006

This paper relates recent empirical research on the growth. Smaller and younger firms have been growing more quickly than larger and older firms, thus, generating proportionately more new jobs. It is not difficult to understand why small and medium firms receive so much attention. Because SMEs provide about 80 percent of private sector employment so SMEs performance is an important economic and social factor. Despite this, they are subject to higher risk and mobility than those at the large firms. This paper is analyzes the relationship between firm growth measured as growth in employment, sales and production and firms age, size and R&D investment. The growth and its relationship with the determinants is linked to industrial policy in Korea. Empirical results are based on an unbalanced panel data covering period 1999-2002. Results show significant relationship between growth, size and age of firm.

• 대한화장품학회지
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• 제24권3호
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• pp.73-80
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• 1998

This Study was performed to get the suitable oil dispersion agent by assessment of color strength of organic pigment in non-aqueous systems. Organic pigment is used as a color expression material with other body pigments in the make-up products. But occasionally aggregation or agglomeration occurs for the lack of affinity with medium, This function is the cause of disturbing homogeneous dispersion, and then bring about an instability of products. Our study, research of dispersion mechanism between the pigment and oil phase, has been executed to solve this problem, and find a oil dispersion agent having optimum dispersion condition. Generally dispersion is related to between the solid-liquid mutual properties and electrical phenomena associated with solid-liquid interface. This factor is determined to input energy, milling time, optical properties, particle size, rheological properties, etc. Ideal dispersion state is told that coloring primary solid particle is homogeneously dispersed in medium. Good dispersed colorants are strongly and clearly appeared. We are already known that the particle size of organic pigment, chemical properties and viscosity of medium, refractive index. Consequently We determine the affinity of medium and organic pigment by measuring of color strength in the same mechanical condition. UV-VISIBLE RECORDING SPECTRO PHOTOMETER is used for measuring apparatus. We can decided the dispersion level of oil dispersion agent by measuring absorbance of color strength in the visible range that diluted medium for colloid colorant particles.

• Journal of Plant Biology
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• 제28권2호
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• pp.141-148
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• 1985

당근(Daucus carota L.) 세포 배양시 무성배 발생에 미치는 세포의 크기, 세포의 밀도, conditioned medium및 배지의 pH효과를 구명하기 위하여 실험한 결과는 다음과 같다. 세포배양시 구상형 배의 발생은 배양 4일째 최대에 달했으며 그 이후부터는 심장형 및 어뢰형 배로 발달되었다. 세포의 밀도가 높을수록 배 발생수가 증가하였으며 MS배지보다는 conditioned medium에서 양호하였고 배의 발달도 촉진되었다. 세포의 크기가 작을수록 생체중 및 배의 형성수가 증가하였으며 9o$\mu\textrm{m}$이상의 세포에서는 현저히 억제되었다. 배지의 pH가 4.0 혹은 7.0일때는 세포의 건물중이 현저히 감소하였고 배의 발생도 억제되었다. 그러나 pH 6에서 건물중이 최대에 달하였고 배의 발생도 양호하였다.