• Computers and Concrete
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• v.32 no.5
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• pp.439-454
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• 2023

In this article, the surface stress effects on the buckling analysis of the annular sandwich plate is developed. The proposed plate is composed of two face layers made of carbon nanotubes (CNT) reinforced composite with assuming of fully bonded to functionally graded porous core. The generalized rule of the mixture is employed to predict the mechanical properties of the microcomposite sandwich plate. The derived potentials energy based on higher order shear deformation theory (HSDT) and modified couple stress theory (MCST) is solved by employing the Ritz method. An exact analytical solution is presented to calculate the critical buckling loads of the annular sandwich plate. The predicted results are validated by carrying out the comparison studies for the buckling analysis of annular plates with those obtained by other analytical and finite element methods. The effects of various parameters such as material length scale parameter, core thickness to total thickness ratio (hc/h), surface elastic constants based on surface stress effect, various boundary condition and porosity distributions, size of the internal pores (e0), Skempton coefficient and elastic foundation on the critical buckling load have been studied. The results can be served as benchmark data for future works and also in the design of materials science, injunction high-pressure micropipe connections, nanotechnology, and smart systems.

• Advances in aircraft and spacecraft science
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• v.4 no.5
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• pp.543-553
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• 2017

Vibration is a source of performance degradation in all optical imaging systems. Performance of high resolution remote sensing payloads is often limited due to satellite platform vibrations. Effects of Linear and high frequency sinusoidal vibrations on the system MTF are known exactly in closed form but the low frequency vibration effects is a random process and must be considered statistically. Usually the vibration MTF budget is defined based on the mission requirements and the overall MTF limitations. For analyzing low frequency effects, designer must know all the systems specifications and parameters. With a good understanding of harmful vibration frequencies and amplitudes in the system preliminary design phase, their effects could be removed totally or partially. This procedure is cost effective and let the designer to eliminate just harmful vibrations and avoids over-designing. In this paper we have analyzed the effects of low-frequency platform vibrations on the payload's modulation transfer function. We have used a statistical analysis to find the probability of imaging with a MTF equal or greater than a pre-defined budget for different missions. The worst and average cases have been discussed and finally we have proposed "look-up figures". Using these look-up figures, designer can choose the electro-optical parameters in such a way that vibration effects be less than its pre-defined budget. Furthermore, using the results, we can propose a damping profile based on which vibration frequencies and amplitudes must be eliminated to stabilize the payload system.

• Hwankyungkyoyuk
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• v.25 no.1
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• pp.66-76
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• 2012

The purpose of this study was to investigate the effects of and development of the STEAM-based on environmental programs to enhance environmental literacy of elementary school students. Through the questionnaires and the analysis of students' outcomes, the effects on literacy in both quality and quantity were verified. By applying the STEAM-based to environmental programs for enhancing environmental literacy to elementary students, the results of this study was as follows: First, its application was meaningful in that the level of $p$<.05 in point view of environmental literacy was a result of the pre-post test in the experiment group, which was made up of the 6th graders in the elementary school. Second, analysis of students' reflective journals showed that the participants' understanding, actions, and attitudes were positively affected by the programs in terms of environmental literacy. In conclusion, the STEAM-based on environmental programs for environmental education was very effective in enhancing environmental literacy.

• Genomics & Informatics
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• v.20 no.4
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• pp.49.1-49.7
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• 2022

Many packages for a meta-analysis of genome-wide association studies (GWAS) have been developed to discover genetic variants. Although variations across studies must be considered, there are not many currently-accessible packages that estimate between-study heterogeneity. Thus, we propose a python based application called Beta-Meta which can easily process a meta-analysis by automatically selecting between a fixed effects and a random effects model based on heterogeneity. Beta-Meta implements flexible input data manipulation to allow multiple meta-analyses of different genotype-phenotype associations in a single process. It provides a step-by-step meta-analysis of GWAS for each association in the following order: heterogeneity test, two different calculations of an effect size and a p-value based on heterogeneity, and the Benjamini-Hochberg p-value adjustment. These methods enable users to validate the results of individual studies with greater statistical power and better estimation precision. We elaborate on these and illustrate them with examples from several studies of infertility-related disorders.

• The Korean Journal of Health Service Management
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• v.8 no.1
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• pp.135-150
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• 2014

The purpose of this study was to identify the effects of nursing simulation-based practice education on learning outcome and teaching experience in nursing students. Pretest-posttest design with nonequivalent control group was utilized to analyze the effects of nursing simulation-based practice education. The subjects were 96 students of a nursing college. All subjects participated in 6 week. The data were analyzed by the SPSS win 17.0 program. The results were as follows; There were statistically significant differences in learning outcome and teaching experience effects of nursing simulation-based practice education in nursing students. In conclusion, we required nursing simulation-based practice education and small group discussion analysis of factors are associated with goal-setting skills and self-presentation skills, goal setting skills. We required nursing simulation-based practice education training to strengthen the ability of self-directed learning program utilizing the repeated study.

• Geomechanics and Engineering
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• v.12 no.2
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• pp.327-346
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• 2017

Laminated plates have many applications in different industrials. Buckling analysis of these structures with the nano-scale reinforcement has not investigated yet. However, buckling analysis of embedded laminated plates with nanocomposite layers is studied in this paper. Considering the single-walled carbon nanotubes (SWCNTs) as reinforcement of layers, SWCNTs agglomeration effects and nonlinear analysis using numerical method are the main contributions of this paper. Mori-Tanaka model is applied for obtaining the equivalent material properties of structure and considering agglomeration effects. The elastic medium is simulated by spring and shear constants. Based on first order shear deformation theory (FSDT), the governing equations are derived based on energy method and Hamilton's principle. Differential quadrature method (DQM) is used for calculating the buckling load of system. The effects of different parameters such as the volume percent of SWCNTs, SWCNTs agglomeration, number of layers, orientation angle of layers, elastic medium, boundary conditions and axial mode number of plate on the buckling of the structure are shown. Results indicate that increasing volume percent of SWCNTs increases the buckling load of the plate. Furthermore, considering agglomeration effects decreases the buckling load of system. In addition, it is found that the present results have good agreement with other works.

• The Journal of Korean Academic Society of Nursing Education
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• v.29 no.3
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• pp.203-224
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• 2023

Purpose: This study aimed to evaluate the effectiveness of simulation-based education on communication and clinical judgment in nursing students and nurses. Methods: A systematic review and meta-analysis were conducted in accordance with the PRISMA guidelines. Seven databases were searched to obtain articles published in Korean or English. Of 12,864 articles reviewed, 36 were included in a systematic review and 23 in a meta-analysis. To estimate the size of the effects of simulation-based education, a meta-analysis was performed using the R package meta program. The risk of bias was assessed using RoB 2.0 and ROBINS-I. Results: The effect sizes (ES) of simulation-based education on communication and clinical judgment were ES=0.77, 95% confidence interval (95% CI)=0.43 to 1.12 on communication-related variables and ES=1.84, 95% CI=1.03 to 2.65 on clinical judgment. Conclusion: Simulation-based education for nursing students and nurses is useful for improving their communication and clinical judgment. Thus, it is necessary to develop and apply simulation-based education programs for nursing students and nurses to improve their abilities in communications and clinical judgment.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.3
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• pp.554-565
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• 2016

This study analyzed expressive effects of King Henry VIII's costumes in films based on DeLong's (1988) theory. Theoretical analysis was done through a literature research of previous studies from both domestic and international. Empirical research was used as a research tool for visual media such as , , and . An analysis on movie costumes indicated that King Henry VIII's costume almost matched DeLong's (1998) expressive effect on excitement, calmness, strength, and delicacy. King Henry VIII's costumes in films based on DeLong's (1988) theory expressed significant of strength and excitement in terms of expressive effects with some elegance. King Henry VIII's costumes had their expressive effects different according to the intentions of film productions, even for the identical event scenes with the same purpose. The findings of this study can be used as basic data for the research of design and costumes as well as the production of drama stages for historical dramas during King Henry VIII's reign.

• Ocean and Polar Research
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• v.38 no.1
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• pp.71-79
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• 2016

In this study, we attempt to examine the economic impacts of the CCS marine geological storage demonstration project in Korea using Input-Output analysis utilizing the inter-industry relation table issued in 2013. In particular, this study defines the $CO_2$ ocean storage industry and then added the inter-industry relation table and treated the $CO_2$ ocean storage industry as exogenous. In addition, this study assumed two scenarios based on the means of $CO_2$ transport, which are pipe and ship. After defining the industry and scenarios, this study investigates the production-inducing effect, value added inducing effect, and employment-inducing effect of the industries associated with the $CO_2$ ocean storage industry based on a demand-driven model. The results pertaining to the scenarios are estimated as follows: total production-inducing effects, value added inducing effects, and employment-inducing effects are calculated as 1.9044 won, 1.2487 won and 16.7224 people/billion won, respectively. In addition, compared to other industries, the indirect economic impacts of the $CO_2$ ocean storage industry are ranked high: the rankings of production-inducing effects, value added inducing effects, and employment-inducing effects are fourth, second, and fifth, respectively.

• Journal of Engineering Education Research
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• v.4 no.2
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• pp.3-10
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• 2001

Recently, as the use of the Internet and the Web becomes universal, there has been a great deal of efforts to use it for education. The advantage of a Web-based lecture is that people can take it anywhere at a low cost anytime. Therefore, its prospect is very bright and its potential customers abound. The demand for java programming education using the Web is increasing. This paper compares and analyzes the learning effects of Web-based and traditional lectures in a java programming course, using statistical inference. Based on the analysis result, it concludes that the learning effects of the Web-based lecture are less effective than those of traditional lecture. Also, it recognizes weak points of Web-based lecture in java programming education and proposes a scheme for enhancing Web-based lectures.