•Thermal optimization of the fin geometry was performed using the Taguchi and ANOVA.•Correlation equations were formulated for amplifier temperature and fin volume.•The order of importance of the fin ...parameters for temperature and volume was determined.•By optimizing, the amplifier temperature decreased by 8.31% and 51.91% of material was saved.•The most effective parameters on the amplifier temperature and fin volume were determined.
In the rapidly advancing field of electronic power supplies, managing thermal performance is critical. This study focuses on optimizing fin geometries to enhance the thermal management of an amplifier used in car multimedia systems, utilizing Taguchi and ANOVA methods for both thermal and volumetric efficiencies. Analyses were conducted on the impact of five distinct fin parameters—fin gap, fin thickness, separated plate thickness, fin base thickness, and fin height—on the system’s thermal behavior and the fin volume. Computational Fluid Dynamics (CFD) analyses were performed for 24 different configurations. These analyses showed significant potential for improvement in the original design, with optimizations leading to an 8.31% reduction in the amplifier temperature and a 51.91% reduction in the fin volume. The study identifies fin height as the most effective parameter on the amplifier temperature, with an effect rate of 57.26%, while fin base thickness showed the most significant effect on the fin volume, with an effect rate of 66.98%. These findings not only provide a basis for more efficient design but also offer predictive insights through formulated regression equations, thus reducing the dependency on extensive experimental setups.
•The corrosion inhibition performance of 2-Mercaptobenzothiazole (2-MBT) was optimized using RSM approach.•The interaction between 2-MBT concentration and temperature had the most significant effect ...on the CIE and CR.•The optimal conditions were determined through numerical and graphical methods for simultaneous maximizing CIE and minimizing CR.•The Langmuir isotherm model could fully show the adsorption behavior of 2-MBT on the metal surface.
In this work, the corrosion inhibition performance of 2-mercaptobenzothiazole (2-MBT) was investigated for carbon steel in 1 M HCl by examining the simultaneous effects of temperature, immersion time, and inhibitor dosage. Design and optimization of the corrosion inhibition have been performed using response surface methodology (RSM). The effectiveness of the inhibitor was analyzed by determining the corrosion rate (CR) and corrosion inhibition efficiency (CIE) using the experimental weight loss method. Based on experimental data and using ANOVA (analysis of variance), two high-precision models have been established to predict CR and CIE. The results depicted that the impact of concentration and temperature on CR and CIE was stronger than immersion time. It was observed that at low concentrations (10–50 ppm), the inhibition performance of 2-MBT was not significant. Increasing the temperature from 30 to 70 °C remarkably decreased CIE by about 14–20% and increased CR by 8–14 mm/y. In addition, it was found that adding 140–160 ppm of 2-MBT at low-to-mean temperature levels (30–50 °C) has the greatest interaction effect on the inhibition performance. In this case, the CIE was more than 92% and CR less than 1 mm/y. Moreover, the process was numerically optimized to “maximize” CIE and “minimize” CR. The results of numerical optimization indicated that optimal conditions for maximum corrosion inhibition performance of 2-MBT (CIE = 94.92%, and CR = 0.72 mm/y) were obtained to be 140 ppm, 34 °C, and 70 h. Furthermore, the type of adsorption of 2-MBT has been examined in the immersion time and temperature ranges of 5–105 h and 30–70 °C. Four models of isotherm for the adsorption analysis were used: Langmuir, Freundlich, Temkin, and Flory Huggins. The best results were observed using the Langmuir isotherm.The presence of both physical and chemical adsorption of 2-MBT was detected. This finding was supported by the range of values for the free energy of adsorption, spanning from −33.72 to −37.16 kJ.mol−1.
Researchers often rely on analysis of variance (ANOVA) when they report results of experiments. To ensure that a study is adequately powered to yield informative results with an ANOVA, researchers ...can perform an a priori power analysis. However, power analysis for factorial ANOVA designs is often a challenge. Current software solutions do not allow power analyses for complex designs with several within-participants factors. Moreover, power analyses often need
η
p
2
or Cohen’s f as input, but these effect sizes are not intuitive and do not generalize to different experimental designs. We have created the R package Superpower and online Shiny apps to enable researchers without extensive programming experience to perform simulation-based power analysis for ANOVA designs of up to three within- or between-participants factors. Predicted effects are entered by specifying means, standard deviations, and, for within-participants factors, the correlations. The simulation provides the statistical power for all ANOVA main effects, interactions, and individual comparisons. The software can plot power across a range of sample sizes, can control for multiple comparisons, and can compute power when the homogeneity or sphericity assumption is violated. This Tutorial demonstrates how to perform a priori power analysis to design informative studies for main effects, interactions, and individual comparisons and highlights important factors that determine the statistical power for factorial ANOVA designs.
Modification of asphalt pavement materials by using recycled waste tires in form of crumb rubber (CRM) is getting significant importance for saving resources as well as protecting ecosystem. So, in ...this study the crumb rubber size and percentage content effect on the performance properties of binder and mixtures were evaluated. A detailed experimental program has been performed using design expert software considering the variables like rubber size and content and their responses which were viscosity, Indirect Tensile strength (ITS), Tensile strength ratio (TSR) durability and Resilient Modulus (Mr). The viscosity of control binder with the addition of crumb rubber at high temperatures showed good improvement. The performance properties viz., ITS, TSR and Mr showed similar behavior as the size and content of crumb rubber increased under different loading conditions. The statistical models prepared using the analysis tool were found significant and well fitted based on high R2 (>0.80), high adequate precision value (>4), insignificant lack of fit and low p-value. Analysis of variance (ANOVA) model theoretical results generated by the response surface methodology (RSM) analysis were further validated by the experiments with <5 % of error showing good agreement between theoretical and experimental results. Study results showed that modified binder with 10 % crumb rubber passing sieve No. 40 in mixtures showed good improvement of mechanical properties indicating the potential source of recycled waste material usage in the pavement construction.
•Recycled waste tires for saving natural resources and protecting ecosystem.•The effect of crumb rubber content showed improvement in the binder performance.•A detailed experimental program using design expert software.•Crumb rubber inclusion in HMA indicated good mechanical performance.
As any real-life data, data modeled by linear mixed-effects models often contain outliers or other contamination. Even little contamination can drive the classic estimates far away from what they ...would be without the contamination. At the same time, datasets that require mixed-effects modeling are often complex and large. This makes it difficult to spot contamination. Robust estimation methods aim to solve both problems: to provide estimates where contamination has only little influence and to detect and flag contamination. We introduce an R package, robustlmm, to robustly fit linear mixed-effects models. The package's functions and methods are designed to closely equal those offered by lme4, the R package that implements classic linear mixed-effects model estimation in R. The robust estimation method in robustlmm is based on the random effects contamination model and the central contamination model. Contamination can be detected at all levels of the data. The estimation method does not make any assumption on the data's grouping structure except that the model parameters are estimable. robustlmm supports hierarchical and non-hierarchical (e.g., crossed) grouping structures. The robustness of the estimates and their asymptotic efficiency is fully controlled through the function interface. Individual parts (e.g., fixed effects and variance components) can be tuned independently. In this tutorial, we show how to fit robust linear mixed-effects models using robustlmm, how to assess the model fit, how to detect outliers, and how to compare different fits.
This study examines the effect of different drying processes on the quality characteristics of arabica coffee in Karot Village, Langke Rembong Subdistrict, Manggarai Regency. Employing an ...experimental design with a two-factor analysis of variance, the research evaluates three drying methods: Before Drying Process, Sun Drying Process, and Drying Process With Coffee Drying House. Results indicate that sun-drying coffee with a coffee drying house yields coffee with lower moisture content, acidity, and caffeine value compared to alternative drying techniques. The research contributes to enhancing the quality of coffee exports from Karot Village, Langke Rembong District, Manggarai Regency. Notably, this study marks a significant original contribution to the area, representing the first such investigation conducted in this locality.
La manufactura aditiva es una herramienta en el desarrollo e innovación para elaborar productos, por lo que en este trabajo se realiza un análisis, por medio de un modelo estadístico denominado ...ANOVA, para identificar tendencias de análisis en entornos de ingeniería aplicada y de investigación. Se realizaron las mediciones correspondientes a las piezas elaboradas en tres máquinas de impresión para corroborar la eficiencia de cada equipo, análisis dimensional y, por último, eficiencia en instrumentos de medición, utilizando el procedimiento de ANOVA en dos factores, con ambientes computacionales. El espécimen se fabrica con PLA (Ácido Poliláctico) en equipos por deposición de material fundido (FDM), con relleno del 30%. Como parte de los resultados del análisis se determina la funcionalidad de las impresoras para obtener un espécimen, evaluando desde el punto de vista control de procesos estadísticos e identificando que las impresoras no mantienen condiciones iguales en procesamiento de especímenes de prueba.
This article provides a Bayes factor approach to multiway analysis of variance (ANOVA) that allows researchers to state graded evidence for effects or invariances as determined by the data. ANOVA is ...conceptualized as a hierarchical model where levels are clustered within factors. The development is comprehensive in that it includes Bayes factors for fixed and random effects and for within-subjects, between-subjects, and mixed designs. Different model construction and comparison strategies are discussed, and an example is provided. We show how Bayes factors may be computed with BayesFactor package in R and with the JASP statistical package.
Translational Abstract
This article provides a Bayes factor approach to multiway analysis of variance (ANOVA) that allows researchers to state graded evidence for effects or invariances as determined by the data. ANOVA is conceptualized as a hierarchical model where levels are clustered within factors. The development is comprehensive in that it includes Bayes factors for fixed and random effects and for within-subjects, between-subjects, and mixed designs. Different model construction and comparison strategies are discussed, and an example is provided. We show how Bayes factors may be computed with BayesFactor package in R and with the JASP statistical package.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ
The aim of the research is to measure the effect of students' use of the strategy of writing questions and answering them on their achievement performance. The researcher used the achievement test to ...measure the differences between variables, and checked the research tool from validity-consistency-experimental application. But for the implementation of the research experiment, the students were divided into three groups, namely: The experimental group 1 (generating questions and answering them by the learners in groups), the experimental group 2 (forming and answering the questions of the learners individually), and the control group (forming questions by the teacher). In addition, the researcher used the mean and standard deviation to answer the research question and compare student performance in all three research groups. The results showed that there were significant differences between the averages of the research groups, as the experimental group 2 achieved a higher average (26,474) than the experimental group 1 (24,333) and the control group (24,857).
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