• International Journal of Concrete Structures and Materials
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• v.8 no.2
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• pp.99-116
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• 2014

The American Concrete Institute (ACI) 318-11 permits the use of the moment magnifier method for computing the design ultimate strength of slender reinforced concrete columns that are part of braced frames. This computed strength is influenced by the column effective length factor K, the equivalent uniform bending moment diagram factor $C_m$ and the effective flexural stiffness EI among other factors. For this study, 2,960 simple braced frames subjected to short-term loads were simulated to investigate the effect of using different methods of calculating the effective length factor K when computing the strength of columns in these frames. The theoretically computed column ultimate strengths were compared to the ultimate strengths of the same columns computed from the ACI moment magnifier method using different combinations of equations for K and EI. This study shows that for computing the column ultimate strength, the current practice of using the Jackson-Moreland Alignment Chart is the most accurate method for determining the effective length factor. The study also shows that for computing the column ultimate strength, the accuracy of the moment magnifier method can be further improved by replacing the current ACI equation for EI with a nonlinear equation for EI that includes variables affecting the column stiffness and proposed in an earlier investigation.

• International Journal of Railway
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• v.8 no.1
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• pp.5-9
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• 2015

Reliability based limit state design method is replacing traditional deterministic designs such as allowable stress design and/or ultimate strength design methods in world trends. European design code(Eurocode) has adopted limit state design, and Korea road bridge design standard has also recently been transferred to limit state design method. In this trend, Korea railroad design standard is also preparing for adopting the same design concept. While safety factors are determined empirically in traditional design, load combinations as well as load factors are determined by solving limit state equations. General partial safety factors are evaluated by using AFORM(Advanced First Order Reliability Method) in the reliability based limit state design method. In this study sensitivity analysis is carried out for a dead load factor and a live load factor. Relative precisions of the dead load and the live load factors are discussed prior to the AFORM analysis. Furthermore the sectional forces of design and the material quantities required by two different design methods are compared for a PSC box girder railway bridge.

• Steel and Composite Structures
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• v.51 no.6
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• pp.601-617
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• 2024

This work aims to explore the static behaviour of a tapered functionally graded porous plate (FGPP) with even and uneven porosity distributions resting on two parametric elastic foundations. The plate under investigation is subjected to bi-sinusoidal loading and the edges of the plate are exposed to different combinations of edge restrictions. In order to examin the static behaviour, bending factors (BF) related to bending and normal stresses have been evaluated using classical plate theory. To achieve this, the governing equations have been derived employing the energy concept. And to solve it, the Rayleigh-Ritz method with an algebraic function has been utilised; it is simple, precise, and computationally intensive. After convergence and validation analyses, new findings are made available. The BF of the plate have been exhaustively examined to explain the influence of aspect ratios, material property index, porosity factor, taper factor, and Winkler and Pasternak stiffness. It is observed that the BF of an elastically supported FGPP are influenced by the index of material propery and the aspect ratio. Findings also indicate that the impact of porosity is more when it is spread evenly, as opposed to when it is unevenly distributed. Further, the deformed plate's structure is significantly influenced by the different thickness variations. Examination of bending characteristics of FGPP having different new cases of thickness variations with different types of porosity distribution under fifteen different mixed edge constraints is the prime novality of this work. Results presented are reliable enough to be taken into account for future studies.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.5
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• pp.949-954
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• 2011

This paper presents a comparative study on motor characteristics with specific consideration of radial vibration force in interior permanent magnet synchronous motors (IPMSM) according to pole/slot combinations. Three IPMSM models, 16-pole/15-slot design, 16-pole/18-slot design and 16-pole/24-slot design are built, in which 16-pole/15-slot and 16-pole/18-slot designs provide high winding factor and 16-pole/24-slot design is known as a general pole/slot combination. By coupling finite element analysis (FEA) with equivalent circuit method, motor characteristics, back electro-motive force (Back-EMF), inductances, cogging torque, etc. as well as machine output performances are analyzed and compared. The radial vibration force (RVF) distribution in air gap causing stator vibration and noise is interested. It is expected that this study help with appropriate choice of pole/slot combination in IPMSM design.

• Korean Journal of Human Ecology
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• v.13 no.6
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• pp.1007-1021
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• 2004

The purpose of this study is to find out the effect of wearers' body types and clothes' neutral tone combination on impression formation. The experimental materials developed for this study are a set of stimulus and response scales(7-point semantic). The stimulus include 45 pictures manipulated by computer simulation in wears' body types and neutral tone variation. The subjects are 540 female undergraduate students in Gyeong-nam. The results of this study are as follows: Impression factor of the stimulus consisted of 5 different dimensions including tenderness, cuteness, attractiveness, elegance, intrepidity. Each impression of neutral tone combinations, along with wears' body types, had a significant effect on tenderness, attractiveness, and intrepidity. Especially, it had the strongest effects on attractiveness. Each impression of wearers' body types along with neutral tone combinations affected cuteness significantly. According to the fact above, wears' body types and neutral tone combination have a significant influence on the impression formation of wearers.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.705-715
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• 2014

Metabolic syndrome is a major factor for cardiovascular disease that can develop into a variety of complications such as stroke disease. This study utilizes a Bayesian network to model metabolic syndrome. In addition, we tried to find the best risk combinations to diagnose metabolic syndrome. We confirmed that the combinations are difference according to individual characteristics. The paper used data from 4,489 adults who responded to all health interview questions from the the $5^{th}$ Korea National Health and Nutrition Examination Survey conducted in 2010.

• Communications for Statistical Applications and Methods
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• v.15 no.4
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• pp.497-507
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• 2008

Confounding techniques have to be used repeatedly in the situations where it is necessary to perform only 2 runs under homogeneous conditions in $2^m$ factorial and fractional factorial experiment. Combinations of confounded $2^m$ factorial and fractional factorial designs enable the estimation of all main effects and all of or a part of 2 factor interaction effects. Defining contrast are used for our designs and treatment combinations of designs to be run are presented.

• Journal of the Korean housing association
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• v.26 no.3
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• pp.77-84
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• 2015

The purpose of this study is to analyze the aesthetic factors in color combinations of house exteriors in hillside villages, Busan. The so-called 'Hillside renaissance' is a representative urban regeneration project in Busan. The towns in hillside area in Busan have developed colorful sceneries. But all the colorful sceneries are not the same. Each town has own color characters and different aesthetic color effects. This study is to determine the unique aesthetic components in color combination of Gamcheon and Daecheong. This study is based on the traditional color harmony theories. The analysis focuses, inter alia, on Moon-Spencer's 'Aesthetic Measure'. A house exterior color has relations with two neighboring colors in array. And those three colors with next two houses have again each three hue, value and chroma relations. This analysis is first to determine whether each sample color combination is harmonized, and if harmonized, next step to list which aesthetic factor is dominantly contributing to color harmony. And at last, to study the subcategorized sectors of each color components of the hue, value and chroma.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.865-872
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• 2017

For more than 10 years, the laser process has been studied for dismantling work; however, relatively few research works have addressed the effect of high-power fiber laser cutting for thick sections. Since in the nuclear sector, a significant quantity of thick material is required to be cut, this study aims to improve the reliability of laser cutting for such work and indicates guidelines to optimize the cutting procedure, in particular, nozzle combinations (standoff distance and focus position), to minimize waste material. The results obtained show the performance levels that can be reached with 10 kW fiber lasers, using which it is possible to obtain narrower kerfs than those found in published results obtained with other lasers. Nonetheless, fiber lasers appear to show the same effects as those of $CO_2$ and ND:YAG lasers. Thus, the main factor that affects the kerf width is the focal position, which means that minimum laser spot diameters are advised for smaller kerf widths.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.581-590
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• 2003

The purpose of this study was to identify the combinations of factors combinations conferring the highest utility of family restaurants to university students, and establish the relative importance of these factors in terms of their contribution to total utility. 196 of 200 questionnaires were utilized for the analysis. (Eds note: to whom were the questionnaires administered) Frequencies, crosstabs, and the conjoint, max. utility, BTL and Logit models, K-means cluster and one-way ANOVA analysesis, and the Friedman test were the statistical methods used for this study. The findings from this study were as follows: 1) the Pearson's R and Kendall's tau statistics (Eds note: these were not mentioned earlier) show that the model (Eds note: which model is this) fits the data well. 2) it was found that of all the respondents, especially the first and third clusters, regarded both the type of food and the price as very important factors. 3) it was found that all the respondents, especially the third cluster, most preferred a family restaurant (design and simulation) that provided less than 6 fusion and traditional foods. The first cluster most preferred family restaurant (design) that provided over 10 traditional and less than 6 ethnic foods. The second cluster most preferred a family restaurant (design and simulation) that provided over 10 traditional foods. 4) the results of the study have provided some insights into the effective types of family restaurant designs that can be successfully developed by those who manage menu variety, quality and type of food, price, and quality of service to university students dining at family restaurants.