• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.1
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• pp.56-73
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• 2019

Probe-based systems have been gaining popularity in advanced traveler information systems. However, the high possibility of providing inaccurate travel-time information due to the inherent time-lag phenomenon is still an important issue to be resolved. To mitigate the time-lag problem, different prediction techniques have been applied, but the techniques are generally regarded as less effective for travel times with high variability. For this reason, current 5-min aggregated data have been commonly used for real-time travel-time provision on highways with high travel-time fluctuation. However, the 5-min aggregation interval itself can further increase the time-lags in the real-time travel-time information equivalent to 5 minutes. In this study, a new scheme that uses both individual probe and 5-min aggregated travel times is suggested to provide reliable real-time travel-time information. The scheme utilizes individual probe data under congested conditions and 5-min aggregated data under uncongested conditions, respectively. As a result of an evaluation with field data, the proposed scheme showed the best performance, with a maximum reduction in travel-time error of 18%.

• Journal of the Korea Society of Computer and Information
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• v.27 no.6
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• pp.95-107
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• 2022

This study attempted to develop a bodice prototype suitable for the 20's obese male's trunk with a BMI of 25kg/m² or more, which is distinguished from the standard body type. Through this, it was intended to provide data to help the development of clothing for obese males. Patterns such as front bodice shoulder line and front sagging were modified through primary appearance and garment pressure evaluation. Through the second evaluation, corrections such as back armhole, back waistline, and front sagging were performed. Through the third evaluation, the final pattern drafting method was developed by removing the front sagging added through the second evaluation. In the case of obese male body types in their 20s, a drafting method distinguished from the standard body type was required in the method of setting the front and back waist lines, back armhole darts, and front shoulder lines due to protruding and posture of the abdomen. This study was meaningful in that it presented a bodice prototype drafting method suitable for the 20s obese males. In the follow-up study, it is thought that actual clothing experiments and studies to develop clothing patterns by applying them to obese male tops in their 20s should be conducted.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.365-368
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• 1998

2차원으로 제도, 재단 과정을 거친 의복 패턴이 3차원의 형상을 갖는 의복으로 만들어져 인체와의 접촉의 결과 생기는 착장 상태를 확인하는 작업에 3차원 의복 CAD 시스템을 이용하면, 직접 재단 봉제 시착(찰볼) 등 일련의 과정을 거치지 않고도, 만들어진 의복의 형상과 착장 상태를 확인해볼 수 있다는 장점이 있다. 이러한 3차원 시스템에서는 의복의 자연스런 처짐, 이른바 드레이프(4.ape)를 잘 표현하여야만 실제에 최대한 가까운 의복의 형상을 보여줄 수 있다. (중략)

• Computational Structural Engineering
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• v.11 no.3
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• pp.241-252
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• 1998

본 논문은 신경망 근사 해석 모델의 원형을 스터브 거더의 거동 해석에 적용하고, 이 과정 중에 발생한 문제점을 파악하여 해결책을 제시함으로써, 앞서 개발한 원형 모델을 스터브 거더 시스템에 적합하도록 발전시키는데 목적이 있다. 스터브 거더의 해석 변수는 주어진 시간 내에 시뮬레이션이 가능하게 7개, 해석 결과값은 탄성 처짐뿐만 아니라 응력까지 고려하여 총 4개의 결과값을 동시에 고려하고, 학습 패턴 수는 총 143개를 사용하였다. 근사해석의 정확도를 향상시키고 학습의 수렴성을 보장하기 위하여 다양한 시뮬레이션을 수행하여 은닉층 뉴런 수, 학습 패턴 그리고 최대 에러의 관계를 규명하고, 이 결과를 바탕으로 신경망 근사 해석 모델 개발 단계를 수정하여 제안하였다.

• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.373-383
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• 2006

In a steel structural system, noncomposite form deck one-way slab is the plate element supported by four-edged steel beams with unequaled stiffness. However, design criterion has analyzed the one-way slab as the continuous beam. Because the end beams that support the one-way slab have elastic supports t hat cause different deflections according to the support conditions and locations, the bending moments corresponding to the support ic support effect is not considered in the design criterion. Accordingly, to conduct a reasonable estimation of approximate moment coefficients considering the unequaled elastic support conditions, this study analyzes and estimates various models with varia bles for the ratios of live load to dead load and pattern arangements of live loads and span lengths. The analytical methods considering the finite three-dimensional plate element, the two-dimensional elastic support and the infinite stifnes suport are performed.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.299-306
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• 2014

Coating is one of the methods used to solve the problem of corrosion of reinforcement in concrete structures. There are few research reported in the literature regarding the effect of zinc-coating on flexural behavior compared to epoxy coating. The objective of this study was to determine whether zinc-coated rebar adversely affects flexural behavior. Concrete beams reinforced with black or zinc-coated steel were tested in flexure. The test variables included the presence of rebar surface coating with zinc, steel ratio used and cover depth. The study concentrated on comparing crack pattern, crack width, deflection and strain. The ultimate flexural capacity of beams reinforced with zinc-coated bars was not different from that of black steel reinforced beams. The results from deflection and crack width measurements were indicative of no significant variation for the different rebar surface conditions. In addition, it was found that load-strain curve of beam reinforced with zinc-coated steel was similar to that of beam reinforced with zinc-coated steel. Therefore, the test results indicated that the use of zinc-coated rebar had no adverse effect on flexural behavior compared to the use of black rebar.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.44-47
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• 2002

A liner static and dynamic analysis for a golf shaft, which is made of carbon fiber reinforced composite materials, is presented in this study. Major mechanical parameters of golf shafts such as deflection, torsional angel, frequency of vibration(CPM), and kick point are analyzed by finite element method. The effects of major parameters on the performance of golf shafts are also discussed. The results show that the major parameters of golf shafts are strongly dependent on the material properties of fibers and design pattern of golf shafts. The present results will be useful to design sheet-rolled golf shafts.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.137-141
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• 2004

Ship structures are basically an assembly of plate elements and the load-carrying capacity or the ultimate strength is one of the most important criteria for safety assessment and economic design. Also, Structural elements making up ship plated structures do not work separately, resulting in high degree of redundancy and complexity, in contrast to those of steel framed structures. To enable the behavior of such structures to be analyzed, simplifications or idealizations must essentially be made considering the accuracy needed and the degree of complexity of the analysis to be used. On this study, to investigate effect of modeling range, the finite element method are used and their results are compared varying the analysis ranges. The model has been selected from bottom panels of large merchant ship structures. For FEA, three types of structural modeling are adopted in terms of the extent of the analysis. The purpose of the present study is to numerically calculate the characteristics of ultimate strength behavior according to the analysis ranges of stiffened panels subject to uniaxial compressive loads.

• Composites Research
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• v.30 no.1
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• pp.65-70
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• 2017

Carbon fiber reinforced composites have light weight and high mechanical properties. These materials are only applicable in limited shape structure cause by complex curing process and low drapability. To solve this problem, Long Fiber Prepreg Sheet (LFPS) has been proposed. In this research, electric device cover plate was selected and designed by using LFPS. Before the design process, we analyzed the target structure to which the rib structures were applied. And 8-inch tablet PC product was selected. For FE analysis, simple loading and boundary conditions were applied. Stiffness of rib structure was investigated according to the rib pattern and shape changes. Rib pattern and shape were selected based on fixed volume condition analysis results. And uneven rib width model was selected for the best case whose deflection was reduced 6~10% than uniform rib model.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.117-127
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• 2019

The purpose of this study was to analyze the direct measurement data of 40-59 year old middle-aged men from Size Korea's 7th anthropometric survey, and to identify the body shape characteristics and to type the body shape of middle-aged men. Through this, this study aimed to provide basic data necessary for the clothing patterns of middle-aged men with excellent fit. The data was SPSS Ver. 24.0 program analysis. Factors extracted six including body horizontal, vertical, shoulder, waist front length, leg thickness, and shoulder deflections. The body shape of middle-aged men was classified into three types. Type 1 had a thin body circumference, a narrow width, a low height, a short waist front length, and a thin ankle and calf. Type 2 had a high body height, a long waist front length, a normal circumference and width, a thick ankle, a calf, and a sagging shoulder. Type 3 had a large body circumference, a wide body, a wide shoulder, and a long waist front length. A prominent feature of the changes in body shape of middle-aged men is the increase in the circumference and thickness items due to abdominal protrusion and fat accumulation. Therefore, pattern design according to these physical characteristics is considered to be necessary.