• 제목/요약/키워드: Mixed effects model

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Emotional Intelligence Research Trends and Future Research Directions in Korean Journals

  • LEE, Seoyeon;MOON, Jaeseung
    • 산경연구논집
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    • 제12권1호
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    • pp.31-46
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    • 2021
  • Purpose: The purpose of the study is to analyze the characteristics of emotional intelligence and the variables related to emotional intelligence in a comprehensive manner. In addition, the study intends to present research trends and future research directions of emotional intelligence in a Korean context by analyzing the effects of emotional intelligence and its mechanisms. Research Design, Data, and Methodology: 77 KCI listed studies were selected for the analysis, and the research perspective of emotional intelligence, measurement instruments, empirical research and research methods were analyzed. In addition, research directions were suggested based on the analysis results. Results: The results of the analysis were as follows: First, previous researchers used the ability model of emotional intelligence the most. Second, Previous studies tended to focus on behavioral factors as dependent variables affected by emotional intelligence, in addition to attitudes, affection. Third, there were few studies on the antecedents of emotional intelligence, however, most studies dealt with the consequences of emotional intelligence. Fourth, few studies dealt with moderators between emotional intelligence and dependent variables. Fifth, on the research type, most studies were quantitative studies, however, a few of them were qualitative studies (Literature review, in-depth interview). Sixth, with regard to the analysis level, almost all studies were conducted on the individual level of emotional intelligence, and most studies featured a cross-sectional research design (longitudinal research design was rare). Conclusion: First, from the perspective of emotional intelligence, additional research should be focused on not only the ability model of emotional intelligence but also on the trait model or the mixed model in the future. Second, since emotional intelligence is a multidimensional construct, it is necessary to study the profile of emotional intelligence by employing people-centered as well as variable-centered methods. Third, with regard to empirical studies, additional research is needed with respect to not only the emotional intelligence of the subordinate, but also the emotional intelligence of the supervisor (leader) and the emotional intelligence of the group. Fourth, it is necessary to actively utilize not only cross-sectional design but also longitudinal design, and qualitative research and meta-analysis methods should also be adopted.

Genetic parameters of milk and lactation curve traits of dairy cattle from research farms in Thailand

  • Pangmao, Santi;Thomson, Peter C.;Khatkar, Mehar S.
    • Animal Bioscience
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    • 제35권10호
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    • pp.1499-1511
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    • 2022
  • Objective: This study was aimed to estimate the genetic parameters, including genetic and phenotypic correlations, of milk yield, lactation curve traits and milk composition of Thai dairy cattle from three government research farms. Methods: The data of 25,789 test-day milk yield and milk composition records of 1,468 cattle from lactation 1 to 3 of Holstein Friesian (HF) and crossbred HF dairy cattle calved between 1990 and 2015 from three government research farms in Thailand were analysed. 305-day milk yield was estimated by the Wood model and a test interval method. The Wood model was used for estimating cumulative 305-day milk yield, peak milk yield, days to peak milk yield and persistency. Genetic parameters were estimated using linear mixed models with herd, breed group, year and season of calving as fixed effects, and animals linked to a pedigree as random effects, together with a residual error. Univariate models were used to estimate variance components, heritability, estimated breeding values (EBVs) and repeatability of each trait, while pairwise bivariate models were used to estimate covariance components and correlations between traits in the same lactation and in the same trait across lactations. Results: The heritability of 305-day milk yield, peak milk yield and protein percentage have moderate to high estimates ranging from 0.19 to 0.45 while days to peak milk yield, persistency and fat percentage have low heritability ranging from 0.08 to 0.14 in lactation 1 cows. Further, heritability of most traits considered was higher in lactation 1 compared with lactations 2 and 3. For cows in lactation 1, high genetic correlations were found between 305-day milk yield and peak milk yield (0.86±0.07) and days to peak milk yield and persistency (0.99±0.02) while estimates of genetic correlations between the remaining traits were imprecise due to the high standard errors. The genetic correlations within the traits across lactation were high. There was no consistent trend of EBVs for most traits in the first lactation over the study period. Conclusion: Both the Wood model and test interval method can be used for milk yield estimates in these herds. However, the Wood model has advantages over the test interval method as it can be fitted using fewer test-day records and the estimated model parameters can be used to derive estimates of other lactation curve parameters. Milk yield, peak milk yield and protein percentage can be improved by a selection and mating program while days to peak milk yield, persistency and fat percentage can be improved by including into a selection index.

The Effect of Different Inflows on the Unsteady Hydrodynamic Characteristics of a Mixed Flow Pump

  • Yun, Long;Dezhong, Wang;Junlian, Yin;Youlin, Cai;Chao, Feng
    • International Journal of Fluid Machinery and Systems
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    • 제10권2호
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    • pp.138-145
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    • 2017
  • The problem of non-uniform inflow exists in many practical engineering applications, such as the elbow suction pipe of waterjet pump and, the channel head of steam generator which is directly connect with reactor coolant pump. Generally, pumps are identical designs and are selected based on performance under uniform inflow with the straight pipe, but actually non-uniform suction flow is induced by upstream equipment. In this paper, CFD approach was employed to analyze unsteady hydrodynamic characteristics of reactor coolant pumps with different inflows. The Reynolds-averaged Naiver-Stokes equations with the $k-{\varepsilon}$ turbulence model were solved by the computational fluid dynamics software CFX to conduct the steady and unsteady numerical simulation. The numerical results of the straight pipe and channel head were validated with experimental data for the heads at different flow coefficients. In the nominal flow rate, the head of the pump with the channel head decreases by 1.19% when compared to the straight pipe. The complicated structure of channel head induces the inlet flow non-uniform. The non-uniformity of the inflow induces the difference of vorticity distribution at the outlet of the pump. The variation law of blade to blade velocity at different flow rate and the difference of blade to blade velocity with different inflow are researched. The effects of non-uniform inflow on radial forces are absolutely different from the uniform inflow. For the radial forces at the frequency $f_R$, the corresponding amplitude of channel head are higher than the straight pipe at $1.0{\Phi}_d$ and $1.2{\Phi}_d$ flow rates, and the corresponding amplitude of channel head are lower than the straight pipe at $0.8{\Phi}_d$ flow rates.

구조 모델링 특성에 따른 복합재료 무힌지 로터의 공력 탄성학적 안정성 연구 (Assessment of Structural Modeling Refinements on Aeroelastic Stability of Composite Hingeless Rotor Blades)

  • 박일주;정성남;김창주
    • 한국항공우주학회지
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    • 제36권2호
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    • pp.163-170
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    • 2008
  • 혼합 보 이론과 적정변형 보 이론에 입각한 공탄성 해석 시스템을 결합하여 유연면을 갖는 복합재료 무힌지 로터에 대한 정지 및 전진 비행시의 공탄성 해석을 수행하였다. 블레이드에 작용하는 공기력은 Leishman-Beddoes의 비정상 공력 모델을 이용하여 구했다. 인장, 회전면 내외의 굽힘, 그리고 비틀림이 상호 연계된 블레이드에 대한 운동방정식은 Hamilton의 원리에 입각하여 유도하였다. 헬리콥터 블레이드의 공탄성 해석에 주요한 요소들인 단면 벽의 두께, 탄성연계, 그리고 구성방정식에 대한 적합한 가정과 같은 주요 구조 모델링 문제들에 대한 효과들을 고찰하였다. 이러한 요소들은 블레이드 단면의 복합재료 적층 구조에 민감하게 반응하며, 블레이드 안정성에도 적지 않은 영향을 나타냄을 보였다.

The design of an ejector type microbubble generator for aeration tanks

  • Lim, Ji-Young;Kim, Hyun-Sik;Park, Soo-Young;Kim, Jin-Han
    • Membrane and Water Treatment
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    • 제10권4호
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    • pp.307-311
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    • 2019
  • The ejector type microbubble generator, which is the method to supply air to water by using cavitation in the nozzle, does not require any air supplier so it is an effective and economical. Also, the distribution of the size of bubbles is diverse. Especially, the size of bubbles is smaller than the bubbles from a conventional air diffuser and bigger than the bubbles from a pressurized dissolution type microbubble generator so it could be applied to the aeration tank for wastewater treatment. However, the performance of the ejector type microbubble generator was affected by hydraulic pressure and MLSS(Mixed Liquor Suspended Solid) concentration so many factors should be considered to apply the generator to aeration tank. Therefore, this study was performed to verify effects of hydraulic pressure and MLSS concentration on oxygen transfer of the ejector type microbubble generator. In the tests, the quantity of sucked air in the nozzle, dissolved oxygen(DO) concentration, oxygen uptake rate(OUR), oxygen transfer coefficient were measured and calculated by using experimental results. In case of the MLSS, the experiments were performed in the condition of MLSS concentration of 0, 2,000, 4,000, 8,000 mg/L. The hydraulic pressure was considered up to $2.0mH_2O$. In the results of experiments, oxygen transfer coefficient was decreased with the increase of MLSS concentration and hydraulic pressure due to the increased viscosity and density of wastewater and decreased air flow rate. Also, by using statistical analysis, when the ejector type microbubble generator was used to supply air to wasterwater, the model equation of DO concentration was suggested to predict DO concentration in wastewater.

인구통계적 응집성이 기업성과에 미치는 영향에서 HR 제도의 역할 탐구: 순환근무와 탄력근무를 중심으로 (The Roles of HR Practices in the Relationship between Demographic Cohesion and Firm Performance: Focusing on Job Rotation and Flexible Work Arrangement)

  • 권인수;이하은;김상준
    • 아태비즈니스연구
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    • 제12권4호
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    • pp.193-209
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    • 2021
  • Purpose - The purpose of this study is to specify the relationship between demographic cohesion and firm performance by examining the roles of HR practices, such as job rotation and flexible work arrangement. Design/methodology/approach - This study samples 1,093 firms in Korea and collects their data between 2007 and 2017 from Workplace Panel Survey, a database from Korea Labor Institute. The demographic cohesion is measured using the Herphindal-Hershman index and the firm performance is measured with net incomes. This study employs a fixed-effects model for the estimation of firm performance with respect to demographic cohesion, job rotation, and flexible work arrangement. Findings - There is a positive relationship between demographic cohesion and net incomes. And the relationship is positively moderated by job rotation. However, flexible work arrangement shows a mixed moderation. Research implications or Originality - Differentiated from the studies on demographic diversity, this study shows that demographic cohesion has a mixed impact on firm performance. While demographic cohesion can improve firm performance through trust building, in-group favoritism, and collective identity it entails internal conflicts. However the link between demographic cohesion and firm performance is moderated by job rotation and flexible work arrangement. While there is a positive moderation of job rotation, there is a negative moderation of flexible work arrangement.

융합인재교육(STEAM)을 적용한 초등 수학영재 교육 프로그램의 개발과 적용 효과 (The Development and the Effects of Educational Program applied on STEAM for the Mathematical Prodigy)

  • 이승우;백종일;이정곤
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제16권1호
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    • pp.35-55
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    • 2013
  • 본 연구는 융합인재교육(STEAM)을 적용한 초등 수학영재교육 프로그램을 개발하고, 그 적용 효과를 알아보기 위하여 수행되었다. 연구의 목적을 달성하기 위하여 문헌 고찰을 통해 프로그램을 개발하였고, 프로그램 적용 효과를 알아보기 위해서는 리커트 척도(Likert scale)에 의한 양적자료 수집과 함께 개방형 질문을 포함하였다. 또한, 질적 자료를 수집하여 혼합모형설계(mixed-model design)를 하였다. 본 연구의 연구결과는 다음과 같다. 첫째, 융합인재교육(STEAM)의 융합접근 모형을 만들고 융합인재교육(STEAM)을 적용한 수학 영재 프로그램을 개발하였다. 둘째, 융합인재교육(STEAM)을 적용한 수학 영재 프로그램에 대하여 만족도를 설문을 통하여 분석한 결과, 학습 내용과 학습 활동에 대한 만족도는 높았으나 학생용 수업자료의 구성에 대한 만족도는 낮다는 것을 알 수 있었다. 셋째, 융합인재교육(STEAM)을 적용한 수학 영재 프로그램 학습내용 중 흥미로웠던 부분과 어려웠던 부분에 대한 질의에는 영재학생들 모두 'STEAM 학습 내용의 수학적 원리'라고 응답하였다. 넷째, 융합인재교육(STEAM)을 적용한 수학 영재 프로그램의 수업에 대한 질적 증거 자료를 수집하여 분석한 결과, 학생들이 수학적 영역 중 각과 속도에 관한 부분에서 창의력과 문제해결능력이 증진된 것으로 확인 되었다. 특히 앵그리버드 게임의 수학적 원리가 어려움에도 불구하고, GeoGebra 환경에서 학생들 자신이 만든 '앵그리버드 게임'에 대해 자신감과 만족감을 나타내는 것을 확인 할 수 있었다.

넙치(Paralichthys olivaceus)의 성장형질 연관 유전자 변이 탐색을 위한 전장유전체연관분석(GWAS) 알고리즘 비교 분석 연구 (Comparison of Genome-wide Association Study (GWAS) Algorithms for Detecting Genetic Variants Associated with Growth Traits in Olive Flounder Paralichthys olivaceus)

  • 윤상원;이희건;박종원;정민환;이다인;정효선;김주란;양혜림;이승환;이정호
    • 한국수산과학회지
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    • 제56권4호
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    • pp.411-418
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    • 2023
  • Genome wide association studies (GWAS) identify genetic loci associated with quantitative traits in genomic selection. Although several studies have compared performance of various algorithms, no study compares them in olive flounder Paralichthys olivaceus. This study compared the GWAS results of four mixed linear model (MLM) algorithms and one Fixed and random model Circulating Probability Unification (FarmCPU) algorithm in olive flounder. Considering gender and genetic association matrices as fixed and random effects, the MLM had stable performance without inflation for λGC (genomic inflation factor) of -log10P. The FarmCPU algorithm had some appropriate λGC of -log10P, and an upward tail was identified in quantile-quantile plots. Therefore, the models were suitable for detecting genetic variants associated with olive flounder growth traits. Moreover, significant genotypes appeared several times at chromosome 22, around which quantitative trait loci are expected to exist. Finally, in both models, some of the most genetic variants were found in genes related to growth traits, confirming their reliability. These results will be helpful when applied to the genomic selection of olive flounder growth traits in the future.

Genetic Relationship between Carcass Traits and Carcass Price of Korean Cattle

  • Kim, Jong-Bok;Kim, Dae-Jung;Lee, Jeong-Koo;Lee, Chae-Young
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권7호
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    • pp.848-854
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    • 2010
  • The objectives of this study were to estimate genetic parameters for the carcass price and carcass traits contributing to carcass grading and to investigate the influence of each carcass trait on the carcass price using multiple regression and path analyses. Data for carcass traits and carcass prices were collected from March 2003 to January 2009 on steers of Korean cattle raised at private farms. The analytical mixed animal model, including slaughter house-year-month combination, linear and quadratic slaughter age as fixed effects and random animal and residual effects, was used to estimate genetic parameters. The effects of carcass traits on the carcass price were evaluated by applying multiple regression analyses. Heritability estimates of carcass traits were $0.20{\pm}0.08$ for carcass weight (CWT), $0.33{\pm}0.10$ for back fat thickness (BFT), $0.07{\pm}0.05$ for eye-muscle area (EMA) and $0.25{\pm}0.10$ for marbling score (MS), and those of carcass prices were $0.21{\pm}0.10$ for auction price per 1 kg of carcass weight (AP) and $0.13{\pm}0.07$ for total price (CP). Genetic correlation coefficients of AP with CWT and MS were $-0.35{\pm}0.29$ and $0.99{\pm}0.04$, respectively, and those of CP with CWT and MS were $0.59{\pm}0.22$ and $0.39{\pm}0.29$ respectively. If an appropriate adjustment for temporal economic value is available, the moderate heritability estimates of AP and CP might suggest their potential use as the breeding objectives for improving the gross incomes of beef cattle farms. The large genetic correlation estimates of carcass price variables with CWT and MS implied that simultaneous selection for both CWT and MS would be also useful in enhancing income.

Estimation of Genetic Correlations and Selection Responses for Carcass Traits between Ultrasound and Real Carcass Measurements in Hanwoo Cows

  • Son, Jihyun;Lee, Deukhwan
    • Journal of Animal Science and Technology
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    • 제55권6호
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    • pp.501-508
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    • 2013
  • This study was conducted to determine genetic correlations among carcass traits measured by ultrasound and real carcass measurements and to estimate indirect selection responses for real carcass traits based on ultrasound measurements in Hanwoo cows. To accomplish this, 22,080 ultrasound measurement records from 17,926 cows collected from 2001 to 2012 and 11,907 carcass records obtained from fattened cattle from 2008 to 2012 were used. Genetic parameters were estimated based on eye muscle area (EMA), backfat thickness (BF) and marbling score (MS) measured by ultrasound-scanning of live cows and using the official technique on chilled bovine half-carcasses after slaughtering. Heritability and genetic correlation for carcass traits were estimated using a mixed model equation that consisted of environmental effects as fixed parameters and additive genetic effects and residual effects as random parameters, assuming that traits were different between ultrasound and carcass measurements. This statistical method was applied to the average information restricted maximum likelihood method. The heritability of EMA, BF and MS measured by ultrasound were 0.33, 0.61 and 0.46, respectively, while the heritability estimates of the corresponding traits based on carcass measurements were 0.29, 0.40 and 0.38, respectively and the genetic correlation between ultrasound and carcass traits for EMA, BF and MS were 0.41, 0.78 and 0.67, respectively. The genetic correlation between ultrasound and carcass traits was highly positive. Additionally, the selection response for marbling score was estimated to be 0.42 per generation if the cows were selected based on the ultrasound scan marbling score with an assumed selection intensity of 0.8. Overall, these results indicate that the ultrasound scan technique would be applicable to judging cow selection for genetically improved meat quality.