• Structural Engineering and Mechanics
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• 제55권2호
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• pp.379-398
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• 2015

Confinement is known to have important influence on ductility of high-strength concrete (HSC) members and it may therefore be anticipated that this parameter would also affect notably the moment redistribution in these members. The correctness of this "common-sense knowledge" is examined in the present study. A numerical test is performed on two-span continuous reinforced HSC beams with and without confinement using an experimentally validated nonlinear model. The results show that the effect of confinement on moment redistribution is totally different from that on flexural ductility. The moment redistribution at ultimate limit state is found to be almost independent of the confinement, provided that both the negative and positive plastic hinges have formed at failure. The numerical findings are consistent with tests performed on prototype HSC beams. Several design codes are evaluated. It is demonstrated that the code equations by Eurocode 2 (EC2), British Standards Institution (BSI) and Canadian Standards Association (CSA) can well reflect the effect of confinement on moment redistribution in reinforced HSC beams but the American Concrete Institute (ACI) code cannot.

• 아동학회지
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• 제9권1호
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• pp.63-80
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• 1988

The main purpose of this study was to investigate the relationships of children's creativity to field independence-dependence cognitive style and demographic variables at age 5. The subjects for the present study were 86 five-year-old boys and girls selected from two kindergartens in Seoul and their parents, who replied to the questionnaire about demographic variables. Children were tested in groups, with the Torrance tests of Creative Thinking-Figural, and individually with the Preschool Embedded Figures Test. The data were analyzed by one way ANOVA, t-test, and Pearson's product-moment correlations. Children's fluency and originality in creativity showed significant positive correlations with field dependent-independent cognitive style. There were no significant differences in creativity according to sex. There were significant differences in field dependent-independent cognitive style according to sex. The score of field independent cognitive style of boys were significantly higher than those of girls. Children's creativity showed low correlations with demographic variables.

• International Journal of Automotive Technology
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• 제6권6호
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• pp.571-577
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• 2005

Combustion of turbulent sprays in a direct injection diesel engine is modeled by the conditional moment closure (CMC) model. The CMC routines are combined with the KIVA code to provide conditional flame structures to determine mean state variables, instead of mean reaction rates. An independent transport equation is solved for each flame group with equal mass of sequentially evaporating fuel vapor. CMC calculation begins as the fuel mass for each flame group begins to evaporate with corresponding initialization conditions. Comparison is made with measured pressure traces for four operating conditions at different rpm's and injection conditions. Results show that the CMC model with multiple flame histories can successfully be applied to ignition and mixing-controlled combustion phases of a diesel engine.

• 한국자기공명학회논문지
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• 제7권1호
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• pp.16-24
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• 2003

Nuclei with the spin quantum number not smaller than unity have not only the nuclear magnetic moment but also the electric quadrupole moment. The quadrupole moment couples with the electric field gradient (EFG) to produce the nuclear quadrupole interaction. It is well known that two independent parameters, i.e. the quadrupole coupling constant (QCC) and the asymmetry parameter ($\eta$) together with the principal axis directions can fully describe the interaction and are very sensitive to the local symmetry and structure of the solid. In order to obtain quantitative estimates of the EFG tensor for various simple ionic configurations surrounding the nucleus under consideration, we employ the simple point charge approximation and apply the calculated results to some real crystals. General agreement is rather satisfactory.

• 설비공학논문집
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• 제25권11호
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• pp.612-616
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• 2013

A circular CAV damper has been developed, based on the investigation of the pressure loss, and the flow-resisting moment by the damper blade. When a torsional spring is attached to the damper axle, and the setting angle is adjusted to around $82^{\circ}$, the volume rate across the damper is almost independent of the static pressure. Such a CAV characteristic appears at an opening angle between $40^{\circ}$ and $60^{\circ}$, where the normalized moment decreases linearly with the angle. In addition, by adjusting the setting angle, the volume rate can be controlled to within 10% error, regardless of the pressure loss.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.321-328
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• 2003

The objective of this study is to investigate the seismic response of high-rise RC bearing-wall structures with irregularity. For this purpose, three 1:12 scale 17-story reinforced concrete model structures were constructed according to the similitude law, in which the upper 15 stories have a bearing-wall system while the lower 2-story frames have three different layouts of the plan : The first one is a moment-resisting frame system, the second has a infilled shear wall with symmetric plan and the third has a infilled shear wall with eccentricity, Then, these models were subjected to a series of earthquake excitations. The test results show the followings: 1) the existence of shear wall reduced greatly shear deformation at the piloti frame, but has almost the negligible effect on the reduction of the overturning-moment angle, 2) the frame with shear wall resists most of overturning moment in severe earthquake, 3) the torsional behavior is almost independent of the translational, 4) the absorbed energy due to the overturning deformation has the largest portion in the total absorbed energy.

• 한국지능시스템학회논문지
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• 제15권5호
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• pp.581-587
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• 2005

본 논문에서는 1차 모멘트와 뉴우턴법의 고정점 알고리즘 독립성분분석을 조합한 얼굴인식 기법을 제안하였다. 여기서 1차 모멘트는 입력되는 얼굴영상의 중심좌표를 계산하는 것이며, 이는 얼굴을 중심 이동하여 인식에 불필요한 배경을 배제시킴으로써 인식성능을 개선시키기 위함이다. 고정점 알고리즘의 독립성분분석은 통계적으로 독립인 얼굴특징들의 집합인 기저영상을 빠르게 얻기 위함이다. 제안된 기법을 64*64 픽셀의 48개(12명*4장) 얼굴영상을 대상으로 city-block, Euclidean, 그리고 negative angle의 3가지 거리 척도를 분류척도로 이용하여 실험하였다. 실험결과, 제안된 기법은 전처리과정을 거치지 않는 단순히 독립기저영상만을 이용하는 기법보다 우수한 인식성능이 있음을 확인하였다. 특히 city-block이 Euclidean이나 negative angle의 거리척도보다 상대적으로 정확하게 유사성을 측정할 수 있었다.

• Journal of the Korean Data and Information Science Society
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• 제18권1호
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• pp.259-267
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• 2007

We consider parametric estimation in a half-normal variable and a UMVUE of its right-tail probability. Also we consider estimation of reliability in two independent half-normal variables, and derive k-th moment of ratio of two same variables.

• 자동차안전학회지
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• 제5권1호
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• pp.37-43
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• 2013

This paper describes an investigation into coordinated control of electronic stability control (ESC) and active roll control system (ARS). The coordinated control is suggested to improve the vehicle stability and agility features by yaw rate control. The proposed integrated chassis control algorithm consists of a supervisor, control algorithms, and a coordinator. The supervisor monitors the vehicle status and determines desired vehicle motions such as a desired yaw rate and desired roll motion based on control modes to improve vehicle stability. According to the corresponding the desired vehicle dynamics, the control algorithm calculated a desired yaw moment and desired roll moment, respectively. Based on the desired yaw moment and the desired roll moment, the coordinator determines the brake pressures and the ARC motor torques based on control strategies. Closed loop simulations with a driver-vehicle-controller system were conducted to investigate the performance of the proposed control strategy using CarSim vehicle dynamics software and the integrated controller coded using Matlab/Simulink.

• 비파괴검사학회지
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• 제24권4호
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• pp.362-370
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• 2004

In this work, the collapse moment due to wall-thinning defects is estimated by using fuzzy neural networks. The developed fuzzy neural networks have been applied to the numerical data obtained from the finite element analysis. Principal component analysis is used to preprocess the input signals into the fuzzy neural network to reduce the sensitivity to the input change and the fuzzy neural networks are trained by using the data set prepared for training (training data) and verified by using another data set different (independent) from the training data. Also, two fuzzy neural networks are trained for two data sets divided into the two classes of extrados and intrados defects, which is because they have different characteristics. The relative 2-sigma errors of the estimated collapse moment are 3.07% for the training data and 4.12% for the test data. It is known from this result that the fuzzy neural networks are sufficiently accurate to be used in the wall-thinning monitoring of elbows.