• Title/Summary/Keyword: multiple comparison analysis

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Deformation-based seismic design of concrete bridges

  • Gkatzogias, Konstantinos I.;Kappos, Andreas J.
    • Earthquakes and Structures
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    • v.9 no.5
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    • pp.1045-1067
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    • 2015
  • A performance-based design (PBD) procedure, initially proposed for the seismic design of buildings, is tailored herein to the structural configurations commonly adopted in bridges. It aims at the efficient design of bridges for multiple performance levels (PLs), achieving control over a broad range of design parameters (i.e., strains, deformations, ductility factors) most of which are directly estimated at the design stage using advanced analysis tools (a special type of inelastic dynamic analysis). To evaluate the efficiency of the proposed design methodology, it is applied to an actual bridge that was previously designed using a different PBD method, namely displacement-based design accounting for higher mode effects, thus enabling comparison of the alternative PBD approaches. Assessment of the proposed method using nonlinear dynamic analysis for a set of spectrum-compatible motions, indicate that it results in satisfactory performance of the bridge. Comparison with the displacement-based method reveals significant cost reduction, albeit at the expense of increased computational effort.

A Study on a Conceptual Model for Housing Quality in Urban Area (현대 도시 주거의질(질) 예측을 위한 개념적 모형에 관한 연구 -서울과 대전 지역을 중심으로-)

  • 최목화
    • Journal of the Korean Home Economics Association
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    • v.26 no.2
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    • pp.49-67
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    • 1988
  • The purpose of this study was to present a conceptual model for predicting housing quality. Housing quality was measured in three ways: perceived quality about physical features of houses, perceived level of the quality in comparison with perceived average level I urban area and housing satisfaction. The specific objectives to achieve the purpose were ; 1) to measure the perceived quality about physical features of houses and perceived level of the quality in comparison with the perceived average level I urban 2) to measure the level of housing satisfaction 3) to clarify the causality between the composite variables of housing quality. A final instrument was developed through two stage pilot surveys. The respondents were 1292 homemakers of middle and high economic class in seoul and Daejeon, selected through stratified random sampling technique. Data were collected during March and April, 1986, and analyzed using SPSS and SAS computer packages. The statistics used were frequency, percentage, F-test, Duncan's Multiple Range, x2, Cramer's V, Multiple linear Regression, Path analysis. The major finding were as follows; the variables significantly related to predict the housing quality were found. The simple, composite variables and 3 measures of housing quality were linked using path analysis, thereby a conceptual model predicting housing quality was suggested.

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A Comparison of Parameter Design Methods for Multiple Performance Characteristics (다특성 파라미터설계 방법의 비교 연구)

  • Soh, Woo-Jin;Yum, Bong-Jin
    • Journal of Korean Institute of Industrial Engineers
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    • v.38 no.3
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    • pp.198-207
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    • 2012
  • In product or process parameter design, the case of multiple performance characteristics appears more commonly than that of a single characteristic. Numerous methods have been developed to deal with such multi-characteristic parameter design (MCPD) problems. Among these, this paper considers three representative methods, which are respectively based on the desirability function (DF), grey relational analysis (GRA), and principal component analysis (PCA). These three methods are then used to solve the MCPD problems in ten case studies reported in the literature. The performance of each method is evaluated for various combinations of its algorithmic parameters and alternatives. Relative performances of the three methods are then compared in terms of the significance of a design parameter and the overall performance value corresponding to the compromise optimal design condition identified by each method. Although no method is significantly inferior to others for the data sets considered, the GRA-based and PCA-based methods perform slightly better than the DF-based method. Besides, for the PCA-based method, the compromise optimal design condition depends much on which alternative is adopted while, for the GRA-based method, it is almost independent of the algorithmic parameter, and therefore, the difficulty involved in selecting an appropriate algorithmic parameter value can be alleviated.

Comparison of Genetic Parameter Estimates of Total Sperm Cells of Boars between Random Regression and Multiple Trait Animal Models

  • Oh, S.-H.;See, M.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.7
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    • pp.923-927
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    • 2008
  • The objective of this study was to compare random regression model and multiple trait animal model estimates of the (co) variance of total sperm cells over the active lifetime of AI boars. Data were provided by Smithfield Premium Genetics (Rose Hill, NC). Total number of records and animals for the random regression model were 19,629 and 1,736, respectively. Data for multiple trait animal model analyses were edited to include only records produced at 9, 12, 15, 18, 21, 24, and 27 months of age. For the multiple trait method estimates of genetic and residual variance for total sperm cells were heterogeneous among age classifications. When comparing multiple trait method to random regression, heritability estimates were similar except for total sperm cells at 24 months of age. The multiple trait method also resulted in higher estimates of heritability of total sperm cells at every age when compared to random regression results. Random regression analysis provided more detail with regard to changes of variance components with age. Random regression methods are the most appropriate to analyze semen traits as they are longitudinal data measured over the lifetime of boars.

A Comparison Study on University Research Efficiency Using DEA Analysis: focused on A University Case (DEA를 이용한 대학 연구 효율성 비교 연구 - A 대학 사례를 중심으로 -)

  • Kim, Seonmin
    • Journal of the Korea Safety Management & Science
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    • v.15 no.1
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    • pp.249-258
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    • 2013
  • Data Envelopment Analysis (DEA) is a useful tool to analyze the relative efficiency of decision making units (DMU) characterized by multiple inputs and multiple outputs. This method has been popularly used as an analytical tool to suggest some strategic improvement. To do this, the results of DEA provide decision makers with a single efficiency score, efficient frontier, return to scale, benchmarking decision making units, etc. The purpose of this paper is to evaluate research performance of 38 universities and provide an inefficient university with the way of organizational changes to be an efficient university by using DEA. Various input and output variables are used to identify technical and scale inefficiency. Additionally, we analyze how an inefficient DMU could be changed an efficient DMU based on a case university. This result will give an insight of constructive directions for increasing of research performance to university decision makers.

Multi-block Technique for a duct flow with multiple outlets (다출구 덕트 유동 해석을 위한 복합 격자망 해석방법의 제안)

  • Jeon,Yong-Deok;Lee, Jae-Heon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.4
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    • pp.1416-1425
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    • 1996
  • A numerical method has been proposed to predict 3-dimensional flow in a duct system with multiple outlets. For the duct system, it is supposed that the pressure values are given at multiple outlets while the velocity profile is given at a inlet. To maintain the continuity of pressure distribution between main and branch duct, present method allows that the pressure value taken from analysis of branch duct can be converted to the main duct analysis. The result from present method which can handle the pressure boundary condition closely coincided with that from regular method which can handle the velocity boundary condition only. Furthermore the flow distribution from present method showed good agreement with that from the single block method. From the comparison of the present method with the total pressure method used for engineering duct design, 13% of discrepancy in pressure loss was shown between the main duct inlet and the branch duct outlet.

Classification of Shear Strength according to Breccia Content in Fault Core (단층각력 함량에 따른 전단강도의 분류)

  • Yun, Hyun-Seok;Moon, Seong-Woo;Seo, Yong-Seok
    • Economic and Environmental Geology
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    • v.53 no.2
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    • pp.167-181
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    • 2020
  • Analysis of variance (ANOVA) and multiple comparison analysis were performed for shear strengths categorized by breccia content of 5 wt.% (Case-I), 10 wt.%, (Case-II) and 15 wt.% (Case-III) in fault cores. The relationship between breccia contetnt and shear strength was quantitatively classified by calculating the mean and standard deviation of shear strength for each population in each case and then the grouping the breccia contents that had a statistically similar effect on the dispersion of shear strength. As a result, shear strength was clearly classified into group 1 (breccia content of 0-15 wt.%) and group 2 and 3 (breccia coantent of 15-30 wt.% and 30 wt.% or more) in Case-III. Shear strength of the standard line at breccia content of 15 wt.% were determined to be 43.6 kPa, 77.6 kPa, and 118.6 kPa at each normal stress (54 kPa, 108 kPa, and 162 kPa), respectively. In addition, the distribution range of cohesions is 0-43.6 kPa at breccia content of 15 wt.% or less, and 0-70.0 kPa at 15 wt.% or more. Distribution range of friction angles is 0-45.7 ° at breccia content of 15 wt.% or less, and 16.7-57.5 ° at 15 wt.% or more.

Multiple intelligences and critical thinking disposition in nursing students (간호학생의 다중지능과 비판적 사고 성향)

  • Hwang, Eunhee;Shin, Su Jin
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.21 no.4
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    • pp.433-445
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    • 2014
  • Purpose: This study was conducted to examine relationships between critical thinking disposition and multiple intelligences. Method: Participants were nursing students (N=186) who completed a questionnaire assessing critical thinking disposition and multiple intelligences. Data were analyzed using descriptive statistics, t-test, analysis of variance with post hoc comparison, and Pearson correlation coefficients. Results: For type of multiple intelligences, 32.9% of students had the strongest fit for "interpersonal intelligence" type and 20.1% for "intrapersonal intelligence" type. Mean score for critical thinking disposition was $3.42{\pm}0.37$. Factors related to critical thinking disposition were participation in club activities (F=5.962, p=.001) with a representative role in the club (t=2.140, p=.034). There were significant differences in interpersonal intelligence scores by personality traits (t=2.445, p=.015), participation in club activities (F=10.003, p<.001), and friendship (t=2.539, p=.012); and significant differences in intrapersonal intelligence scores by participation in club activities (F=3.862, p=.010), having a representative role in the club (t=2.101, p=.037), and friendship (t=2.220, p=.029). Conclusion: Results indicate that critical thinking disposition is significantly associated with multiple intelligences and suggest that multiple intelligences should be considered to enhance critical thinking disposition when tailored teaching is adopted in nursing education.

Classification performance comparison of inductive learning methods (귀납적 학습방법들의 분류성능 비교)

  • 이상호;지원철
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1997.10a
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    • pp.173-176
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    • 1997
  • In this paper, the classification performances of inductive learning methods are investigated using the credit rating data. The adopted classifiers are Multiple Discriminant Analysis (MDA), C4.5 of Quilan, Multi-Layer Perceptron (MLP) and Cascade Correlation Network (CCN). The data used in this analysis is obtained using the publicly announced rating reports from the three korean rating agencies. The performances of 4 classifiers are analyzed in term of prediction accuracy. The results show that no classifier is dominated by the other classifiers.

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Analysis of PN Code Acquisition Performance with Multiple Antennas in a UWB System (다중 안테나를 적용한 UWB 시스템의 PN 부호 포착 성능 분석)

  • Kim, Eun-Cheol;Kim, Jin-Young
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.69-72
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    • 2005
  • In this paper, pseudo noise (PN) code acquisition performance with multiple antennas in a UWB time hopping/code division multiple access system is analyzed. The closed form for the conditional probability is derived, using the Gauss-Hermite quadrature formula, when the signal with Gaussian distribution goes through the lognormal fading channel. The performance comparison of the above mentioned schemes shows that the code acquisition performance with a diversity combining technique, especially when increasing the number of antennas, is more robust than that using no diversity.

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