• 한국연초학회지
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• 제6권1호
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• pp.19-24
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• 1984

This study was carried out to find out the variations in Burley 21 variety of Surely tobacco. Jeonjul and nine other selected lines of Burley 21 were evaluated. Plant height and several other characteristics were significantly different among tested lines. Especially, Jangsu-1, the earliest flowered line, flowered 5 to 7 days earlier than other lines and had the smallest length width ratio of the largest leaf. Narrow-leaved type, whose length/width ratio of the largest leaf was above 2, 16, was significantly different in number of leaves and weight per unit leaf area from broad-leaved type whose length/width ratio of the largest leaf being below 1.97. Among tested lines, Jeonju (2) - 2 was the best in major agronomic characteristics, yield and physical properties.

• 한국실내디자인학회논문집
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• 제41호
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• pp.104-111
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• 2003

Most residential buildings in Korea are preferred to have maximum interior spaces, rather than consider its original design, overall building performance, and any other aspects since early 1990's. Especially in high-rise apartment buildings, balcony has been merged to living room to get more interior spaces and this renovation trends have been producing deep and narrow shapes of living rooms that was not initially intended by architects. On the other hand, the same gross area of each unit does not necessarily mean same width and depth ratio of each residential unit. Generally, we can categorize it to the deep or wide unit based on its width and depth ratio. Under these circumstances, this study analyzes the room usage pattern changes based on the space width and depth ratio and the effect of expansion of room space to the balcony. This study also includes about 180 apartments plan case studies to find out the relationships among w/d ratio changes, furniture arrangement types, and room configurations. In this research, general apartment room w/d ratios are 0.97 ∼ 1.23; 0.7(south facing sitting room), 1.23(south facing bed room), and 0.95(north facing bedroom). But, after expanding room space to balcony w/d ratio increased as follows; sitting room become 1.31, general south facing bedroom become 1.23, and north facing bedroom become 1.45. In addition to user preference of w/d ratio, many people prefer rectangular room shape a little(w/d ratio is 0.9 or 1.2) than square style (w/d ratio is 1.0) or very deep room style (w/d ratio Is more over 1.5). Accordingly, expanding the room space to balcony may make unsatisfactory room w/d ratio. Expanding room space to balcony should be considered by existing room w/d ratio.

• 한국지진공학회논문집
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• 제19권2호
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• pp.75-83
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• 2015

The purpose of this study is to improve the previous damage evaluation model for RC members which is proposed by Igarashi[1] in 2010.The previous model was not confirmed by enough data of damage such as, residual crack length, width and area for exfoliation of concrete, etc. In addition, validation of the model is still insufficient. Therefore, experiment of a real-scale RC structure and experiment of RC columns using the high-strength concrete were conducted to gather the data of damage in RC members. The investigation has been conducted gathering the data not only additional experiments data but also existing data for modification of damage evaluation model. It has been investigated on changing damage in RC due to axial force ratio, shear reinforcement and shear span ratio. As a result, several problems were founded in the previous model, such as, hinge length($l_p$), spacing of flexural crack($S_{av,f}$), total width of flexural cracks regulated by maximum width of flexural crack($n_f$) and total width of shear cracks regulated by maximum width of shear crack($n_s$). New model is proposed and evaluated the damage properly.

• 한국정밀공학회지
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• 제21권2호
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• pp.168-176
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• 2004

Interrupted creep tests were carried out on the Mod.9Cr-1Mo steel in order to investigate the structural degradation during creep. The ranges of creep stress and temperature were from 71 to 167MPa and 873 to 923k, respectively. The change of hardness and tempered martensitic lath width were measured in the grip and gauge parts of interrupted specimens. The lath structure was thermally stable in static conditions, but was not stable during creep, and the structural evolution was enhanced by creep strain. The relation between the change in lath width and strain was described in the from, $\delta$W= a ($W_s-W_o$)$cdot;varepsilon$, where $\varepsilon$ is the strain, $W_o$is the initial lath width, $W_s$ is the final lath width depending solely on stress, and a is the constant of the magnitude of 0.67 $\mu$m /strain. The change in Victors hardness was expressed by a one-valued function of creep life consumption ratio. Based on the empirical relation between strain and lath width, a model was proposed to explain the relation between change in hardness and creep life consumption ratio. The model revealed that about 65$%$ of dislocations in lath structures were eliminated by the migration of subboundaries.

• 한국강구조학회 논문집
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• 제24권4호
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• pp.451-458
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• 2012

구조적 우수성이 입증된 콘크리트 충전 강관 (CFT) 시스템은 폭두께비가 큰 강관을 사용할 때 더욱 경제적인 설계가 될 수 있다. 하지만, 현재 국내외의 규준에서는 CFT에 사용할 수 있는 강관의 폭두께비를 제한하고 있어 건설 재료를 보다 더 효율적으로 활용할 수 있는 가능성을 미리 차단하고 있다. 본 연구에서는 폭두께비 60, 70, 80, 90, 100를 갖는 각형 단주 CFT에 대해 압축실험을 실시하여 CFT에서의 좌굴 후 내력을 확인하였고 기존의 규준에서 제시한 폭두께비 제한치를 완화한 식을 제시하였다.

• The Journal of Advanced Prosthodontics
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• 제4권2호
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• pp.72-75
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• 2012

PURPOSE. This study evaluated the existence of golden proportion between the widths of the maxillary and mandibular anterior teeth in Indian population. MATERIALS AND METHODS. The clinical tooth width measurements were recorded with the digital vernier calipers on 576 patients of both sexes in the age group of 21 - 30 years. Flexible ruler was used to determine the width of maxillary and mandibular anterior teeth on the patients by the same operator. The data obtained was statistically analyzed using paired student t-test (${\alpha}$=.05). RESULTS. The golden proportion was not found between the width of the right central and lateral incisors in 53% of women and 47% of men. The results revealed the golden percentage was rather inconstant in terms of relative tooth width. CONCLUSION. The golden proportion is an inappropriate method to relate the successive widths of the maxillary anterior teeth in Indian population.

• 한국가시화정보학회지
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• 제11권2호
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• pp.46-54
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• 2013

Study of the wave structure and shear layer in the vicinity of a wall mounted cavity is done by time averaged colour schlieren and time resolved instantaneous shadowgraph technique in an M=1.7 flowfield. Effect of change of cavity width on flow structure is investigated by using constant length to depth (L/D) ratio cavity models with varying length to width (L/W) ratio of 0.83 to 4. The time averaged shock wave structure was observed to change with change in cavity width. Dependence of the shock angle at the leading edge on the shear layer width is also evident from the images obtained. Unsteadiness in the flow field in terms of shear layer dynamics and quasi steady nature of shock waves was evident from the images obtained during instantaneous shadowgraph experiments. Apart from the leading and trailing edge shocks, several other waves and flow features were observed. These flow features and the associated physical phenomena are discussed in details and presented in the paper.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2544-2547
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• 2008

A micro channel heat sink has been studied and optimized for mixed pressure driven and electroosmotic flows through three-dimensional numerical analysis. The effects of ionic concentration represented by zeta potential and Debye thickness are studied with the various steps of externally applied electric potential. Optimization of the micro channel heat sink has been performed considering two design variables related to the micro channel width, depth and fin width. The surrogate-based optimization is performed using a search algorithm taking overall thermal resistance as objective function. The thermal resistance is found to be more sensitive to channel width-to-depth ratio than fin width-to-depth of channel ratio.

• 설비공학논문집
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• 제22권8호
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• pp.523-529
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• 2010

We investigate two-dimensional laminar flow around rectangular cylinders placed in a uniform stream. Numerical simulations are performed, using finite volume method, in the ranges of $50{\leq}Re{\leq}150$ and $0.1{\leq}W/H{\leq}1.0$, where Re and W/H are the Reynolds number and the width-to-height ratio, respectively. The immersed boundary method is used to handle the rectangular cylinder in a rectangular grid system. Comparisons with the previous results show good agreement in Strouhal number, drag and lift coefficient. The present study reports the detailed information of flow structure at different width-to-height ratios in the ranges of $50{\leq}Re{\leq}150$.

• 한국광학회지
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• 제4권4호
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• pp.447-451
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• 1993

용량이행형 방전회로를 이용하여 장펄스 XeCl 엑시머 레이저를 발진 시켰으며, 펄스폭은 150ns(FWHM)이었다. 펄스폭에 영향을 미치는 가스분압 및 capacitance의 비에 따른 펄스폭의 변화를 관측 하였으며, 이로부터 단펄스에서 장펄스로의 발진을 쉽게 얻을 수 있음을 알았다. 일정 가tm 혼합 비율([Xe]/[HCl]=15)의 상태에서 HCl과 Xe가스의 분압이 감소함에 따라 광 펄스폭의 최대 변화량은 125ns이었고, 일정 압력 하에서의 capacitance비(Cm/Cp) 변화에 늘어나는 광 펄스폭의 변화량은 60ns이었다.