• Title/Summary/Keyword: Mixed Methods

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Aerodynamic Design Program for Centrifugal/Mixed-flow Compressors - Part II : Three Dimensional Profile Design of Impellers - (원심/사류압축기의 공력설계 프로그램 개발 - 제2부 : 임펠러의 3차원 형상설계 -)

  • Oh, Jong-Sik
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.464-468
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    • 2003
  • A general program of three dimensional profile design of impellers for centrifugal/fixed-flow compressors is successfully commercialized using Bezier curves and quasi-3D flow analysis methods. Control points for meridional hub and shroud contours and blade camberline angles are arbitrarily changed to give smooth Bezier curves. With specified blade normal thicknesses, contructed geometry is instantly analyzed using flow analysis methods to be checked.

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Adaptation in Families of Children with Down Syndrome: A Mixed-methods Design (다운증후군 자녀를 둔 가족의 적응력: 혼합적 연구 방법 적용)

  • Choi, Hyunkyung
    • Journal of Korean Academy of Nursing
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    • v.45 no.4
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    • pp.501-512
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    • 2015
  • Purpose: The purpose of this study, which was guided by the Resiliency Model of Family Stress, Adjustment, and Adaptation, was twofold: (a) to explore family and parental adaptation and factors influencing family adaptation in Korean families of children with Down syndrome (DS) through a quantitative methodology and (b) to understand the life with a Korean child with DS through a qualitative method. Methods: A mixed-methods design was adopted. A total of 147 parents of children with DS completed a package of questionnaires, and 19 parents participated in the in-depth interviews. Quantitative and qualitative data were analyzed using stepwise multiple regression and content analysis respectively. Results: According to the quantitative data, the overall family adaptation scores indicated average family functioning. Financial status was an important variable in understanding both family and parental adaptation. Family adaptation was best explained by family problem solving and coping communication, condition management ability, and family hardiness. Family strains and family hardiness were the family factors with the most influence on parental adaption. Qualitative data analysis showed that family life with a child with DS encompassed both positive and negative aspects and was expressed with 5 themes, 10 categories, and 16 sub-categories. Conclusion: Results of this study expand our limited knowledge and understanding concerning families of children with DS in Korea and can be used to develop effective interventions to improve the adaptation of family as a unit as well as parental adaptation.

Conjoint analysis with mixed levels of attributes (혼합된 수준들의 속성들을 갖는 컨조인트 분석)

  • Lim, Yong B.;Chung, Jong Hee
    • Journal of Korean Society for Quality Management
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    • v.44 no.4
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    • pp.799-811
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    • 2016
  • Purpose: The conjoint analyst in marketing are interested in detecting whether there exist synergy or antagonistic effects between two attributes. In the cases where attributes have two or three levels, we research on the design of survey questionnaire to estimate all the main effect and as many two factor interaction effects as possible. Methods: We consider the balanced incomplete block (BIB) mixed level factorial design $2^f{\times}3^g$ or fractional factorial design. To reduce the number of questions in a questionnaire, we propose the balanced incomplete block mixed level design with minimum aberration which is generated by implementing proc factex in SAS. Also, we propose using two or three level BIB factorial design instead of mixed level designs by transforming three level attributes into two attributes of two levels and two level attribute into three level attribute by using dummy level technique. Results: We propose three methods for designing survey questionnaire where the block and design generators are found with practical number of questions in a questionnaire. By analyzing all the respondents survey data generated by the simulation study, we find the proper model and do the concepts optimization. Conclusion: The proposed methods of designing survey questionnaires seem to perform well in the sense that the proper model, and then the optimal concept is found in a case study where all the respondents survey data are generated by the simulation study.

Analysis of Competition Interaction in Orchardfrass , Red Clover Pure and Orchardfrass-Red Clover Mixed Swards (Orchargrass 단파 , Red Clover 단파 및 Orchargrass-Red Clove 단순혼파 목초의 경쟁구조 해석)

  • 이형석;이인덕
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.4
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    • pp.279-284
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    • 1995
  • The competition relationship between orchardgrass(Docflis glomerutu L. cv; Potomac) and red clover (Trifnlium prurense L. cv; Kenland) was investigated under the pure and mixed swards. Each species were grown in intra- and interspecific competition in pots and fields for 2-years. Intra- and interspecific competition were evaluated by calculating traditional methods; expected yield, relative yield total(RYT), aggressivity and compensation index(CI), and shoot and root dry matter production in the orchadgrass(ffi) pure, red clover(RC) pure and orchardgrdss(W)-red clover(RC) mixed sward. The results obtained were summarized as follows: Compared to OG and RC pure swards, the shoot and root dry maaer(DM) yield of OG-RC mixed sward were higher and more deeply rooted under the soil than those of OG and RC pure sward. Also, the number of tillen per plant of OG in the OG-RC mixed sward was less than that of OG pure sward, but that of RC in the OGRC mixed sward was more than that of RC pure sward. OG-RC mixed sward were evaluated as a productive sward type compared to OG and RC pure swards in that actual yield was higher than expect yield and that relative yield total(RYT), and compensation index(C1) were high. As mentioned above, compared to intraspecific competition as a OG and RC pure sward, interspecific competition as a OG-RC mixed sward was evaluated to productive type under the ffi and RC species utilization

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The Impact of Other-Race Perceptual Individuation Training on Five- to Six-Year-Olds' Categorization of Mixed-Race Faces (타인종에 대한 지각적 개별화 연습이 5-6세 유아의 혼합 인종 범주화에 미치는 영향)

  • Kang, Eun;Park, Youjeong
    • Korean Journal of Childcare and Education
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    • v.18 no.2
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    • pp.85-103
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    • 2022
  • Objective: This study examined five- to six-year-old children's categorization of mixed-race faces and how it was affected by perceptual individuation training (PIT) for other-races. Methods: Sixty-five children attending classes for 5-year-olds in childcare centers were shown happy and angry faces of Korean and African American mixed-race people, along with neutral faces of Korean and African American monoracial people. They were asked to categorize the faces into same-race or other-race. After the pretest, participants received a PIT for either African American (other-race) or monkeys. Then the racial categorization task was administered again as a posttest. Results: Children showed no general tendency to categorize mixed-race faces as out-group in the pretest. Yet, the PITs further reduced children's categorization of mixed-race faces as out-group. In particular, the effect was clearly evident in children who received the PIT for other-race. Conclusion/Implications: The results suggest that the tendency to categorize mixed-race faces as an out-group may not be evident in early childhood and that experiences of perceptually identifying other-race individuals may help children view mixed-race individuals as being in the ingroup, at least perceptually.

ASYMPTOTIC STUDY OF MIXED ROTATING MHD SYSTEM

  • Selmi, Ridha
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.2
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    • pp.231-249
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    • 2010
  • Asymptotic behavior of three-dimensional mixed, periodic and rotating magnetohydrodynamic system is investigated as the Rossby number goes to zero. The system presents the difficulty to be singular and mixed, that is hyperbolic in the vertical direction and parabolic in the horizontal one. The divergence free condition and the spectral properties of the penalization operator are crucial in the proofs. The main tools are the energy method, the Schochet's method and products laws in anisotropic Sobolev spaces.

A NONCONFORMING PRIMAL MIXED FINITE ELEMENT METHOD FOR THE STOKES EQUATIONS

  • Cho, Sungmin;Park, Eun-Jae
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.6
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    • pp.1655-1668
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    • 2014
  • In this article, we propose and analyze a new nonconforming primal mixed finite element method for the stationary Stokes equations. The approximation is based on the pseudostress-velocity formulation. The incompressibility condition is used to eliminate the pressure variable in terms of trace-free pseudostress. The pressure is then computed from a simple post-processing technique. Unique solvability and optimal convergence are proved. Numerical examples are given to illustrate the performance of the method.

ERROR ESTIMATION FOR NONLINEAR ELLIPTIC PROBLEMS USING THE h-p-MIXED FINITE ELEMENT METHOD IN 3 DIMENSIONAL SPACE

  • Lee, Mi-Young
    • Bulletin of the Korean Mathematical Society
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    • v.38 no.2
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    • pp.237-260
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    • 2001
  • The approximation properties for $L^2$-projection, Raviart-Thomas projection, and inverse inequality have been derived in 3 dimensional space. h-p-mixed finite element methods for strongly nonlinear second order elliptic problems are proposed and analyzed in 3D. Solvability and convergence of the linearized problem have been shown through duality argument and fixed point argument. The analysis is carried out in detail using Raviart-Thomas-Nedelec spaces as an example.

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Dam Sensor Outlier Detection using Mixed Prediction Model and Supervised Learning

  • Park, Chang-Mok
    • International journal of advanced smart convergence
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    • v.7 no.1
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    • pp.24-32
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    • 2018
  • An outlier detection method using mixed prediction model has been described in this paper. The mixed prediction model consists of time-series model and regression model. The parameter estimation of the prediction model was performed using supervised learning and a genetic algorithm is adopted for a learning method. The experiments were performed in artificial and real data set. The prediction performance is compared with the existing prediction methods using artificial data. Outlier detection is conducted using the real sensor measurements in a dam. The validity of the proposed method was shown in the experiments.

GENERAL MIXED HARMONIC VARIATIONAL INEQUALITIES

  • Jong Kyu Kim;Avinash Lakhnotra;Tirth Ram
    • Nonlinear Functional Analysis and Applications
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    • v.29 no.2
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    • pp.517-526
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    • 2024
  • In this paper, some iterative methods are used to discuss the behavior of general mixed-harmonic variational inequalities. We employ the auxiliary principle technique and g-strongly harmonic monotonicity of the operator to obtain results on the existence of solutions to a generalized class of mixed harmonic variational inequality.