• Title/Summary/Keyword: width difference

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Effect of Finger Dimensions of Tip and Root Widths on Bending Strength Properties (핑거공차가 휨강도성능에 미치는 영향)

  • 변희섭;류현수;안상열;이균필;박한민;김종만
    • Journal of the Korea Furniture Society
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    • v.12 no.2
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    • pp.1-10
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    • 2001
  • As finger joint method has a high rate of yield and high strength and ease in working, it has been widely used as an end joint method for solid wood and wood based-material. Therefore, we end-joined the material of Pinus densiflora, Quercus variabilis and populus euramericana with polyvinyl acetate adhesive and resorcinol phenol resin adhesive. The effect of difference (0, 0.15, 0.3, 0.45mm) between the dimensions of tip width and root width of the finger (DTRW) on bending strength properties was as follows: 1. In the case of polyvinyl acetate adhesive, DTRW had no effect on bending modulus of elasticity(MOE) and modulus of rupture(MOR) of the three kinds of species, because their bonding layers were destroyed by slippage, not their woody parts. 2. In the case of resorcinol phenol resin adhesive, the material of Quercus variabilis showed an optimal result at 0.15 or 0.3 of DTRW, while the poplar did at 0 of DTRW 3. The differences in efficiency ratio of bending MOR of populus euramericana, Pinus densiflora and Quercus variabilis species according to the kind of adhesive were 13-29%, 23-30% and 45-53%, respectively.

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Conjugate Heat Transfer in Cylindrical Annulus for an Insulated Tube (단열관을 위한 원통 환상공간 내에서의 복합 열전달)

  • Kang, B.H.;Yang, S.H.;Kwon, S.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.633-641
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    • 1995
  • The effect of the gap width on conjugate heat transfer in the cylindrical annulus for an insulated tube has been studied numerically by the finite difference method. The parameters considered here are the Rayleigh number, Ra, the dimensionless insulated wall thickness, $W/D_i$ and the dimensionless gap width, S/W. As S/W increases, the mean wall temperature increases at the inside wall of annulus and decreases at the outside walls of annulus and the insulated tube at $S/W{\leq}0.5$, and then slightly increases at $Re=10^4$, $W/D_i=1.47$. The heat transfer rate decreases at $S/W{\leq}0.5$ and then increases apparently as S/W increases at $Re=10^4$, W/Df=1.47. Therefore, it is considered that $$S/W{\sim_=}0.5$$ is the optimum gap width for the effect of insulation at $Re=10^4$, $W/D_f=1.47$.

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Bus-waveguide-width Dependence of Evanescent Wave Coupling in a Microring Resonator

  • Son, Seong-Jin;Kim, Suyeon;Yu, Nan Ei;Ko, Do-Kyeong
    • Current Optics and Photonics
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    • v.5 no.5
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    • pp.538-543
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    • 2021
  • The evanescent wave coupling of a microring resonator is controlled by changing the gap distance between the bus waveguide and the microring waveguide. However, the interdependence of the bus waveguide's width and the coupling is not well understood. In this paper, we investigate the dependence of coupling strength on the bus waveguide's width. The strength of the evanescent wave coupling is analytically calculated using coupled-mode theory (CMT) and numerically calculated by three-dimensional finite-difference-time-domain (FDTD) simulation. The analytic and numerical simulation results show that the phase-matching condition in evanescent wave coupling does not provide maximum coupling strength, because both phase-matching and mode confinement influence the coupling. The analytic and simulation results for the evanescent coupling correspond to the experimental results. The optimized bus-waveguide width that provides maximum coupling strength results in intrinsic quality factors of up to 1.3 × 106. This study provides reliable guidance for the design of microring resonators, depending on various applications.

Impact of adjacent excavation on the response of cantilever sheet pile walls embedded in cohesionless soil

  • Singh, Akshay Pratap;Chatterjee, Kaustav
    • Geomechanics and Engineering
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    • v.30 no.3
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    • pp.293-312
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    • 2022
  • Cantilever sheet pile walls having section thinner than masonry walls are generally adopted to retain moderate height of excavation. In practice, a surcharge in the form of strip load of finite width is generally present on the backfill. So, in the present study, influence of strip load on cantilever sheet pile walls is analyzed by varying the width of the strip load and distance from the cantilever sheet pile walls using finite difference based computer program in cohesionless soil modelled as Mohr-Coulomb model. The results of bending moment, earth pressure, deflection and settlement are presented in non-dimensional terms. A parametric study has been conducted for different friction angle of soil, embedded depth of sheet pile walls, different magnitudes and width of the strip load acting on the ground surface and at a depth below ground level. The result of present study is also validated with the available literature. From the results presented in this study, it can be inferred that optimum behavior of cantilever sheet pile walls is observed for strip load having width 2 m to 3 m on the ground surface. Further as the depth of strip load below the ground surface increases below the ground level to 0.75 times excavation height, the bending moment, settlement, net earth pressure and deflection decreases and then remains constant.

Upper Body Type of Women with Large Busts (가슴이 큰 여성의 상반신 체형 유형)

  • Sujoung Cha
    • Journal of Fashion Business
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    • v.27 no.5
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    • pp.26-43
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    • 2023
  • This study sought to typify and characterize the upper body shape of women with large breasts by classifying only Korean adult women aged 20-69 years whose difference dimension between bust and underbust circumference was 12.5 cm or greater. This study attempted to provide necessary information for the development of upper body clothing for women with large busts. Upper body horizontal, upper body height, shoulder size, upper body length, and shoulder slop factor were extracted to constitute upper body shapes of women with large busts. Upper body shapes of women with large busts were classified into four types: low obese upper body tall body type, high normal upper body short body type, drooping shoulders slender upper body tall body type, and broad shoulders slender upper body short body type. Upper body proportions of women with and without large busts were analyzed as follows. Women with large breasts had narrower shoulder width compared to bust width and waist width. Their underbust and waist circumferences were larger than their bust circumferences. For the development of tops for women with large busts, bodice pattern development was required, taking into account shoulder width, chest, and upper body length. Future studies should focus on angles of busts in more detail. Research should be conducted on the development of bodice by upper body type of women with large busts analyzed.

RSET Analysis According to the Width of Escape Routes in Large Supermarkets (대형마트의 피난로 폭에 따른 RSET 분석)

  • Boohyun Baek;Hongsang Lee;Hasung Kong
    • Journal of the Korea Safety Management & Science
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    • v.26 no.3
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    • pp.29-38
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    • 2024
  • The purpose of this study is to use an evacuation simulation program to measure the change in evacuation time according to the width of the evacuation route due to the installation of an intermediate sales counter and the placement of a shopping cart between the sales counters of a large supermarket and to analyze the results. Currently, the "Distribution Industry Development Act" does not regulate the size and installation method of intermediate sales counters installed between sales counters that serve as practical evacuation routes in the event of a fire at a large supermarket, the size of shopping carts, etc. Considering this, we set evacuation route widths of 40, 50, 60, 70, 80, and 100 cm and compared and analyzed evacuation times according to various variables in the facility space. As a result of the experiment, as the width of the evacuation route was expanded, there was a significant difference in the evacuation time, from a maximum of 468.3 seconds to a minimum of 320.8 seconds. Considering the safety of evacuees in large supermarkets used by many people, it is time to regulate the size of intermediate sales stands installed between sales counters in large supermarkets and shopping carts that can become obstacles in an emergency.

Optimal Design of Arrayed Waveguide Grating

  • Jung, Jae-Hoon
    • Journal of the Optical Society of Korea
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    • v.8 no.3
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    • pp.99-103
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    • 2004
  • This paper describes the optimal design of an AWG spectrum to meet various specifications and improve some physical parameters. The objective function is the norm of the difference between design parameters and target values. To obtain the design parameters, the Fourier model is employed and the design variables arc spacing of array waveguide, width of array waveguide, optical path difference, and focal length. The (1+1) Evolution Strategy is employed as the optimization tool. The optimization procedure is applied to a 16-channel AWG and the optimized design variables will considerably improve the system performance.

Confidence Intervals for the Difference of Binomial Proportions in Two Doubly Sampled Data

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.17 no.3
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    • pp.309-318
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    • 2010
  • The construction of asymptotic confidence intervals is considered for the difference of binomial proportions in two doubly sampled data subject to false-positive error. The coverage behaviors of several likelihood based confidence intervals and a Bayesian confidence interval are examined. It is shown that a hierarchical Bayesian approach gives a confidence interval with good frequentist properties. Confidence interval based on the Rao score is also shown to have good performance in terms of coverage probability. However, the Wald confidence interval covers true value less often than nominal level.

Marginal fit of In-Ceram crown according to shoulder width (In-Ceram 전부도재관의 shoulder 폭경에 따른 변연적합도)

  • Chun, Seung-Geun;Lee, Cheong-Hee;Cho, Kwang-Hyun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.16 no.2
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    • pp.105-112
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    • 2000
  • In-Ceram system is one of contemporary esthetic all ceramic restorations and has relatively high flexural strength. The purpose of this study was to evaluate the marginal fit of In-Ceram crown according to shoulder width and measuring position. In this study, twenty seven In-Ceram crowns devided into three groups, each prepared with shoulder width of 0.6mm, 0.9mm and 1.2mm. All specimens were cemented with glass ionomer cement. After cementation, specimens were measured marginal gap between the margin of the In-Ceram crown and the finishing line of resin master die by using a refrective microscope. Marginal gaps were recorded at the labial, lingual, mesial and distal measuring points on the resin master die. The results of this study were as follows: 1. Mean marginal fits of each group were $81.28{\mu}m$ in 0.6mm shoulder width, $70.78{\mu}m$ in 0.9mm shoulder width and $67.75{\mu}m$ in 1.2mm shoulder width. 2. There was significant difference between group 0.6mm and 0.9mm, 1.2mm.(p<0.05). 3. In comparison of marginal fit according to the measuring points, there was no significant difference.

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A Study on the Safety Navigational Width of Bridges Across Waterways Considering Optimal Traffic Distribution (최적 교통분포를 고려한 해상교량의 안전 통항 폭에 관한 연구)

  • Son, Woo-Ju;Mun, Ji-Ha;Gu, Jung-Min;Cho, Ik-Soon
    • Journal of Navigation and Port Research
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    • v.46 no.4
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    • pp.303-312
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    • 2022
  • Bridges across waterways act as interference factors, that reduce the navigable water area from the perspective of navigation safety. To analyze the safety navigational width of ships navigating bridges across waterways, the optimal traffic distribution based on AIS data was investigated, and ships were classified according to size through k-means clustering. As a result of the goodness-of-fit analysis of the clustered data, the lognormal distribution was found to be close to the optimal distribution for Incheon Bridge and Busan Harbor Bridge. Also, the normal distributions for Mokpo Bridge and Machang Bridge were analyzed. Based on the lognormal and normal distribution, the analysis results assumed that the safe passage range of the vessel was 95% of the confidence interval, As a result, regarding the Incheon Bridge, the difference between the normal distribution and the lognormal distribution was the largest, at 64m to 98m. The minimum difference was 10m, which was revealed for Machang Bridge. Accordingly, regarding Incheon Bridge, it was analyzed that it is more appropriate to present a safety width of traffic by assuming a lognormal distribution, rather than suggesting a safety navigation width by assuming a normal distribution. Regarding other bridges, it was analyzed that similar results could be obtained using any of the two distributions, because of the similarity in width between the normal and lognormal distributions. Based on the above results, it is judged that if a safe navigational range is presented, it will contribute to the safe operation of ships as well as the prevention of accidents.