• 대한방사선기술학회지:방사선기술과학
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• 제31권3호
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• pp.277-285
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• 2008

MRI를 이용하여 정상의 뇌량 크기를 측정한 결과 다음과 같은 결론을 얻었다. 1. 전체 대상자의 부위별 평균, 최소, 최대 1) Anteroposterior length는 평균 69.30mm, 최소 50.70mm, 최대 80.40mm이었다. 2) Diameter of genu는 평균 11.93mm, 최소 6.00mm, 최대 18.50mm이었다. 3) Diameter of mid body는 평균 7.00mm, 최소 3.40mm, 최대 10.40mm이었다. 4) Diameter of narrowing portion은 평균 4.51mm, 최소 0.80mm, 최대 9.50mm이었다. 5) Diameter of splenium은 평균 12.17mm, 최소 6.90mm, 최대 17.20mm이었다. 2. 전체 대상자의 성별에 따른 부위별 비교 1) Anteroposterior length는 남자가 여자보다 컸으며, 성별에 따라 유의미한 차이를 보였다. 2) Diameter of genu와 diameter of mid body, diameter of narrowing portion은 남자가 여자보다 컸으나 유의미한 차이는 아니었다. 3) Diameter of splenium은 남자가 여자보다 컸으며, 통계적으로도 유의미한 차이를 보였다. 3. 전체 대상자의 부위별 상관관계 1) Diameter of genu는 anteroposterior length와 통계적으로 유의미한 정적 상관관계를 보였다. 2) Diameter of mid body는 anteroposterior length, diameter of genu와 통계적으로 유의미한 정적 상관 관계를 보였다. 3) Diameter of narrowing portion은 anteroposterior length와 통계적으로 유의미한 상관관계를 보이지 않았으나 diameter of genu, diameter of mid body와 통계적으로 유의미한 정적 상관관계를 보였다. 4) Diameter of splenium은 anteroposterior length와 diameter of genu, diameter of mid body, 그리고 diameter of narrowing portion과 통계적으로 유의미한 정적 상관관계를 보였다.

• 대한기계학회논문집B
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• 제24권7호
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• pp.957-966
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• 2000

The effect of rotation on the discharge coefficient of orifices with various length-to-diameter ratios and two different inlet corner radii was studied. Length-to-diameter ratios of the orifices range from 0.2 to 10, while the inlet shapes are square edged, or round edges of radius-to-diameter ratio of 0.5. From the experiment, we found that rotational discharge coefficient and Rotation number, when based on ideal exit velocity of the orifice considering momentum transfer from the rotor, describe the effect of rotation very well. In this study, the discharge coefficients of rotating orifices are shown to behave similar to those of the well-known non-rotating orifices. For both rotating and non-rotating orifices, the discharge coefficients increase with the length-to-diameter ratio until a maximum is reached. The flow reattachments in the relatively short orifices are responsible for the increase. The coefficient then decreases with the length-to-diameter ratio due to the friction loss along the orifice bore. The length-to-diameter ratio that yields maximum discharge coefficient, however, increases with the Rotation number because the increased flow-approaching angle requires larger length-to-diameter ratio for complete reattachment. The length-to-diameter ratio for complete reattachment is shorter for round edged orifices than that of square edged orifices by about a unit length-to-diameter ratio.

• Journal of Advanced Marine Engineering and Technology
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• 제33권5호
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• pp.646-652
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• 2009

Experimental results for performance characteristics of HCs refrigerant R-1270 and HCFC refrigerant R-22 during refrigeration system using capillary tube are presented. The system consists of compressor, condenser, capillary tube, evaporator and peripheral devices. Length and diameter of capillary tube are varied for this investigation. The refrigerant mass flow increased as the diameter of capillary tube increased and the length of capillary tube decreased. A refrigeration capacity and compressor work of R-1270 in same length and diameter of capillary tube showed the higher values than those of R-22. A coefficient of performance showed the highest value when the length and diameter of capillary tube are 105 cm and 1.8 mm in this experimental conditions.

• 설비공학논문집
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• 제13권12호
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• pp.1214-1222
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• 2001

The present study investigated the effect of diameter and length on the absorption performance of a vertical falling film type absorber using $LiBr-H_2$O solution of 60 wt%. The parameters were diameter of absorber (17.2, 23.4, 31.1 mm), length of absorber (771, 1150, 1528 mm), and film Reynolds numbers (50, 70, 90, 110, 130, 150). As the diameter of the absorber was increased, the absorption mass flux, Sherwood number, heat flux, and heat transfer coefficient were increased, in which Sherwood number and heat transfer coefficient were increased up to 13% and 30% respectively. As the length of the absorber was increased, the total absorption rate and heat transfer coefficient were increased by 37% and 35% respectively, while the absorption mass flux was decreased.

• 생명과학회지
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• 제7권1호
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• pp.59-65
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• 1997

In this experiment, gene actions were analysized for seven barley parents in order to obtain basic information on their genetic improvement by diallel crosses. The results obtained were summarized as follows. In analysis of variance, additive, dominant, maternal and reciprocal effects were observed significantly for culm length, tiller number, number of spiked per plant, culm diameter, awn length, leaf width, number of grains per spike, and 1000 grain weight. Over-dominance was shown by Vr-Wr graphic analysis in five characters such as tiller number, number of spikes per plant, length of flag leaf, number of grains per spike, and 1000 grain weight, and partial dominance in four characters such as culm length, culm diameter, awn length, and leaf width. Component of genetic varience analyzed for four characters such as culm diameter, awn length, length of flag leaf, and leaf width showed that additive effects were higher than dominant effects. Culm length, tiller number, number of spikes per plant, number of grains per spike, and 1000 grain weight showed dominant effects higher than additive effects. The narrow-sense heritability for awn length, leaf width, and number of grains per spike showed high values as more than 0.62, while broad-sense heritability for culm length, number of spikes per plant, culm diameter, awn length, leaf width, number of grains per spike, and 1000 grain weight showed high values as more than 0.65.

• Journal of Ginseng Research
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• 제7권2호
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• pp.133-147
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• 1983

This study was carried out to obtain the basic information for the development of new ginseng varieties. The two variants (violet-stem variant and yellow-berry variant) of Korean ginseng (Panax ginseng C.A. Meyer) and American ginseng (Panax quinquefolium L.) of one to four-year were used for this study. All of the characteristics, such as leaf length, leaf width, petiol length, number of leaves per plant, number of leaflets per plants, stem diameter, stem length, number of stems per plant, root length, primary root length, root diameter, root weight were determined and correlations among them were estimated. The results obtained were summarized as follows. 1. Leaf length, petiol length, number of leaves per plant, and number of leaflets per plant of Panax ginseng, violet-stem variant and yellow-berry variant, were larger than those of Panax quinquefolium at all of the plant ages, while leaf width was wider in Panax quinquefolium. 2. The length of stem of Panax quinquefolium was shorter than that of Panax ginseng, and the frequency of multi-stem plants at 4-year-old ginseng was larger in violet-stem variant than in Panax quinquefolium and yellow-berry variant. 3. In the characteristics of ginseng root, the primary root length of Panax ginseng, violet-stem variant and yellow-berry variant, were less than that of Panax quinquefolium, while root weight, root diameter, and umber of secondary root related to yield were larger in Panax ginseng. 4. The root weight per plant related to the yield had positive and highly significant correlations with stem diameter, leaf length, leaf length, leaf width, number of compound leaves and leaflets in Panax ginseng and Panax quinguefolium. 5. The root weight related to the wield of ginseng had been influenced to stem diameter, leaf length, and leaf width directly, and number of compound leaves and leaflets indirectly. 6. The number, total area and activity of stomate per mm2 of Panax quinquefolium were more, larger and stronger than those of Panax ginseng.

• 한국항해항만학회지
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• 제32권9호
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• pp.723-727
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• 2008

Sensing performances of evanescent field absorption (EFA) hetero-core fiber sensor has been presented based on EFA by changing the length and the core diameter of the single mode fiber. Experimental results have demonstrated a good feature in their relationship between the length and the core diameter of the single mode fiber. The sensor consists of 2 fiber optics which have the same cladding diameter of $125{\mu}m$ However one fiber optic used is single mode and has varying core diameter ranging from 3.3 to $5.6{\mu}m$. The other fiber is multimode type and has a thicker fixed core diameter of $62.5{\mu}m$. The 2 fiber optics are thermally spliced together. Experiments conducted to measure the resonance wavelength were carried out over a range of refractive index, to find the optimum sensing length Experiments show that core diameter of the single mode fiber and sensing length offects the linearity and sensitivity.

• 생명과학회지
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• 제15권1호
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• pp.132-135
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• 2005

가지 육종을 위한 기초 자료를 얻고자 9품종을 교잡하여 $F_l$ 세대의 11개 조합을 재료로 각 형질들의 측정치로서 우성의 정도와 잡종강세를 평가하였다. $F_l$세대의 잡종강세는 초장, 경경, 과중, 엽장, 엽폭, 주당과수 등이 초우성으로 유전되었다. 그리고 과장과 과경은 불완전 우성으로 유전되었다. Heterosis의 정도는 초장, 경경, 과중, 과장, 과경, 엽장, 엽폭, 주당과수 등 8개 형질 모두에서 정(+)의 강세를 보였다. Heterobeltiosis의 정도는 초장만이 정(+)의 강세를 보였고, 과경, 엽폭, 엽장, 과중, 주당과수, 과장, 경경은 부(-)의 잡종강세를 보였다

• 산업기술연구
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• 제27권B호
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• pp.71-75
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• 2007

A cylindrical pin fin with variable diameter is analyzed by using the one dimensional analytical method. Heat loss and fin efficiency are presented as a function of the fin diameter, length and convection characteristic numbers ratio. The relationship between the fin diameter and convection characteristic number over the fin for the same amount of heat loss is shown. One of the results indicates the fin efficiency increases as the fin diameter increases while that decreases as the fin length increases.

• 한국산업융합학회 논문집
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• 제5권3호
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• pp.201-208
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• 2002

The machine tool which operates by hand is replacing by CNC machine tool to improve the quality of the product and the productivity in modem mechanic industry. The precision of machine part is influenced greatly the surface roughness by cutting condition of machine tool. So this study was performed to examine the aluminium surface roughness of section according to change of strength rating, nose radius, cutting speed, using live center. The results of this study are as follows; 1. In the case of 56mm diameter of test piece(length is below triple of diameter), whether establish the live center or not, doesn't influence to the surface roughness, and it is possible to make product without the live center. 2. The average surface roughness of 42mm diameter(length is quadruple of diameter) is similar to the 56mm diameter in the cutting condition of nose radius 0.8mm and cutting speed 140mm/min, but there are increases and differences in other cutting conditions. 3. In the case of test piece length more 70m/min(140m/mm) and nose radius improved greatly using the live center. 4. In the case of test piece length is quintuple of diameter, the nose radius must choose big tool and increase the cutting speed in preference live center establishment availability to improve that is surface roughness. Conclusively, if aluminum test piece length is fewer than triple of diameter, can process without establishing live center. If aluminum test piece length is more than quintuple of diameter, cutting conditions to improve surface roughness are (1) cutting speed (2) nose radius (3) whether the live center uses or not.