• 한국지진공학회논문집
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• 제15권6호
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• pp.1-10
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• 2011

이 연구는 중공 프리스트레스트 콘크리트 교각의 P-M 상관도에 대한 매개변수 분석을 수행한 결과를 제시하고 있다. 다수의 매개변수 중에 콘크리트 압축강도, PS 강재량, 유효프리스트레스, $D_s/D_o$, 그리고 $D_i/D_o$를 선택하여 P-M 상관도에 미치는 영향을 중점적으로 다루었다. 준정적 실험을 통해서 중공 프리스트레스트 콘크리트 교각 실험체의 강도와 연성도를 평가하였다. 실험 및 해석결과와 각 코드를 기준으로 비교한 P-M상관도의 결과는 서로 다른 차이를 나타내었으며 AASHTO-LRFD는 근접한 값을 보여주었다. 무차 원화한 P-M 상관도를 중공 프리스트레스트 콘크리트 교각의 저항능력을 예측하기 위하여 제시하였다.

• 한국산학기술학회논문지
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• 제13권5호
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• pp.2396-2402
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• 2012

최근 영구거푸집과 보강재 역할을 동시에 하는 FRP-콘크리트 합성부재에 관한 연구가 많이 진행되고 있으며, 일부에서는 실제 교량바닥판에 적용되고 있다. 본 연구에서는 파괴실험으로 평가한 퍼포본드 FRP 콘크리트 합성보에 대해 비선형 유한요소해석 프로그램을 활용하여 검증해석을 실시하고, 이를 이용하여 FRP 보강재 형상에 따른 매개변수 해석을 수행하였다. 퍼포본드 FRP 보강재의 경우 다우웰 영향으로 내력이 증가하는 양상이 나타났고, 본 해석모델을 중심으로 판단하면 웨브의 높이를 고려하여 25~35mm 범위에서 구멍직경을 결정하는 것이 바람직하다고 판단된다.

• Structural Engineering and Mechanics
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• 제54권5호
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• pp.891-908
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• 2015

For a systematic study on wind-induced vibration characteristics of large hyperbolic cooling towers with different feature sizes, the pressure measurement tests are finished on the rigid body models of three representative cooling towers with the height of 155 m, 177 m and 215 m respectively. Combining the refined frequency-domain algorithm of wind-induced responses, the wind-induced average response, resonant response, background response, coupling response and wind vibration coefficients of large cooling towers with different feature sizes are obtained. Based on the calculating results, the parametric analysis on wind-induced vibration of cooling towers is carried out, e.g. the feature sizes, damping ratio and the interference effect of surrounding buildings. The discussion shows that the increase of feature sizes makes wind-induced average response and fluctuating response larger correspondingly, and the proportion of resonant response also gradually increased, but it has little effect on the wind vibration coefficient. The increase of damping ratio makes resonant response and the wind vibration coefficient decreases obviously, which brings about no effect on average response and background response. The interference effect of surrounding buildings makes the fluctuating response and wind vibration coefficient increased significantly, furthermore, the increase ranges of resonant response is greater than background response.

• Journal of Welding and Joining
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• 제30권6호
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• pp.62-67
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• 2012

In this study, the bonding strengths of adhesively bonded joints are experimentally investigated. A series of lap-shear tests are conducted using single lap type adhesive joints. In order to analyse the joint fabrication factors that affected the bonding strength, the parametric tests are conducted with various thickness of adhesive, surface roughness and fillet of adhesive. In addition, for the comparative study with the welded joint, lap-shear tests using specimens with 2 welded sides and 4 welded sides are also carried out. The quantitative results of the strength analysis are summarized, and some proposals are made on setting up testing standards for adhesively bonded joints.

• 대한토목학회논문집
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• 제12권2호
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• pp.161-167
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• 1992

보강재 절단에 의한 보강토옹벽의 파괴시 그의 지내력과 파괴 메카니즘을 조사하기 위하여 원심모형실험을 수행하였다. 보강재의 재질, 길이 및 배열을 변화시키면서 실험을 실시하여 그들이 보강토 옹벽의 지내력에 미치는 영향에 관하여 연구하였다. 실험결과를 분석하고 현재 사용되고 있는 여러 설계방법과 비교 검토함으로써 그들의 사용 타당성을 검증하였다. 그 결과로 적정의 설계방법을 제안하였다.

• Journal of the Korean Statistical Society
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• 제30권4호
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• pp.679-691
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• 2001

Two truncated sequential tests are developed for the two-sample scale problem based on the usual Wilcoxon rank-sum statistic for two different dispersion indices - absolute median deviations, when the medians of the two populations X and Y are equal or known and sums of squared mean deviations, when the medians are either unknown or unequal. The first test is briefly called SWAMD test and the second SWSMD test. For the SWAMD test, the percentile points for both the one-sided and two-sided alternatives, (equation omitted) have been found by Wiener approximation and their values computed for a range of values of a and N; analytical expression for the power function has been derived through Wiener process and its performance studied for various sequential designs for exponential distribution. This test has been illustrated by a numerical example. All the results of the SWAMD test, being directly applicable to the SWSMD test, are not dealt with separately Both the tests are compared and their suitable applications indicated.

• 한국정보처리학회논문지
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• 제7권3호
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• pp.1021-1024
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• 2000

In this paper we describe a nonparametric Wilcoxon test and a parametric Z test based on statistical hypothesis testing for the detection of edges. We use the threshold determined by specifying significance level $\alpha$, while Bovik, Huang and Munson[4] consider the range of possible values of test statistics for the threshold. From the experimental results of edge detection, the Z method performs sensitively to the noisy image, while the Wilcoxon method is robust over both noisy nd noise-free images. Comparison with our statistical tests and Sobel operator shows that our tests perform more effectively in both noisy and noise-free images.

• 대한토목학회논문집
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• 제14권1호
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• pp.195-202
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• 1994

본 연구에서는 모래의 전단파괴 포락선의 곡률특성을 구명하고 전단강도와 Been과 Jefferies가 제시한 상태정수간의 매개변수관계를 밝히기 위하여 많은 압밀배수삼축시험의 결과를 분석하였다. 통상적인 삼축시험에서 시료의 단면적 변화와 멤브레인의 영향에 대한 수정은 특히 한계상태를 결정하는데 중요하다고 할 수 있다. 실험결과로부터 전단강도를 밀도와 응력수준의 함수로 표현하는 모델을 제시하였고 모래의 전단파괴포락선의 곡률특성과 상태정수와 전단강도정수간의 관계를 밝혔다.

• 대한산업공학회지
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• 제41권4호
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• pp.408-413
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• 2015

The quality prediction of the semiconductor industry has been widely recognized as important and critical for quality improvement and productivity enhancement. The main objective of this paper is to predict the final quality of semiconductor chips based on fail bit count information obtained from probe tests. Our proposed method consists of solving the data imbalance problem, non-parametric variable selection, and adjusting the parameters of the model. We demonstrate the usefulness and applicability of the proposed procedure using a real data from a semiconductor manufacturing.

• 국제초고층학회논문집
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• 제5권3호
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• pp.213-220
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• 2016

The "China Zun" tower in Beijing will rise to 528 meters in height and will be the tallest building in Beijing once built. Inspired by an ancient Chinese vessel, the "Zun", the plan dimensions reduce gradually from the bottom of the tower to the waist and then expand again as it rises to form an aesthetically beautiful and unique geometry. To satisfy the structural requirement for seismic and wind resistance, the structure is a dual system composed of a perimeter mega structure made of composite mega columns, mega braces, and belt trusses, and a reinforced-concrete core with steel plate-embedded walls. Advanced parametric design technology is applied to find the most efficient outer-perimeter structure system. The seismic design basically follows a mixed empirical and performance-based methodology that was verified by a shaking table test and other specimen lab tests. The tower is now half-way through its construction.