• International Journal of Concrete Structures and Materials
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• v.10 no.4
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• pp.451-460
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• 2016

An anchorage system is necessary in most reinforced concrete structures for connecting attachments. It is very important to predict the strength of the anchor to safely maintain the attachments to the structures. However, according to experimental results, the existing design codes are not appropriate for large anchors because they offer prediction equations only for small size anchors with diameters under 50 mm. In this paper, a new prediction model for breakout shear strength is suggested from experimental results considering the characteristics of large anchors, such as the prying effect and size effect. The proposed equations by regression analysis of the derived model equations based on the prying effect and size effect can reasonably be used to predict the breakout shear strength of not only ordinary small size anchors but also large size anchors.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.4
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• pp.21-28
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• 2020

PURPOSE: The main purpose of this meta-analysis study was to identify the degree-of-effect size and the variables for the effects of manual physical therapy on myofascial pain syndrome. METHODS: This study collected six studies published between 2015.01.01 and 2019.12.31. The analysis result verified nine effect size data. The random-effect model was chosen because of the heterogeneity of the data. RESULTS: First, the full case showed the largest mean effect size of 2.297 (p < .001). Second, the size of the effect based on the fascial distortion model (FDM) intervention showed an effect size of 4.654 (p < .001). Third, the number of participants showed a 15 or less effect size of 2.612 (p > .058). The number of treatments showed a 10 less effect size of 2.844 (p > .129). The publication type showed a thesis effect size of 3.095 (p < .002). CONCLUSION: Manual physical therapy has a great effect on myofascial pain syndrome in the neck and shoulders, and that the effects differ according to the methods of intervention.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.259-268
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• 2020

The purpose of our study is to conduct a general·quantitative analysis of fandom activities and verify their organization types and effects. The results are as follows. With regard to the comparison of effect size, the variable related to the social and economic field showed the greatest effect size, which was followed by individual behavior and individual mentality. In terms of influential factors of fandom activities, the effect size of positive variables was intermediate level while the effect size of negative variables was low level. In addition, the effect size of fandom supporting idol groups was the greatest, which was followed by of fandoms supporting sports stars, and actors. In terms of the effect size with regard to the influence on fandom among the objects of study, the effect size of university students was the greatest, which was followed by the whole, adult, middle and high school student, and middle school student. Meanwhile, the result of the analysis according to the classification by country showed that China had the greatest effect size, and the US also showed quite a big effect size. On the other hand, South Korea showed a low level of effect size.

• The Journal of Korean Physical Therapy
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• v.33 no.5
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• pp.211-216
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• 2021

Purpose: The main purpose of this meta-analysis was to identify the degree of effect size and variables for the impact of manual physical therapy on the improvement in the range of motion of frozen shoulder patients. Methods: This study collected 8 studies published between 1st January 2010 and 31st December 2020. The analysis of the results verified 49 effect size data and the random effect model was chosen. Results: First, the full case showed the largest mean effect size of 2.485 (p<0.001). Second, the size of the effect based on manual therapy and modality therapy showed an effect size of 4.178 (p<0.001). Third, the outcome group included 6 variables. The external rotation (2.818) variable group showed the largest mean effect size, followed by internal rotation (2.748), flexion (2.643), abduction (2.356), and adduction (2.356). Six outcomes were significant and the mean effect sizes of all the varied groups were above large size. The number of participants showed a 20 or less effect size of 2.478 (p>0.737). The number of intervention periods showed 4 weeks 20 or more effect size of 2.782 (p>0.294). Finally, the 'Trim and Fill' result confirmed that the calibration effect size was 1.471 (p<0.001). Conclusion: This study verified that manual physical therapy had a substantial effect on the improvement of the range of motion of patients with frozen shoulders and that the effects were dependent on the methods of outcomes.

• Computers and Concrete
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• v.23 no.6
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• pp.409-419
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• 2019

In the present study, effect of size and placement of cubic specimens on compressive strength of self-compacting lightweight concrete (SCLC) were considered. To do so, 81 specimens of different sizes (50 mm, 75 mm, 100 mm, and 150 mm) were prepared by using three different mixes of SCLC. Results of the cured specimens were then used in regression analyses to find predictive equations with regard to both the placement direction and the size. Test results showed that the strength ratio in cases in which the direction of loading and placement were parallel, were higher than those specimens, whose configurations were normal between loading and placement. In addition, strength ratios in SCLC mixes were slightly higher than those are for self-compacting normal weight concrete. In order to analyze the effect of size on compressive strength the conventional size effect law as well as the modified size effect law (MSEL) were used. Besides, the convergence criterion of nonlinear regression process of size effect study has been discussed. Analyses of the results showed that the unconstraint nonlinear regression in size effect study of SCLC mixes could lead to erroneous results.

• Computers and Concrete
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• v.28 no.5
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• pp.521-532
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• 2021

Present paper focuses on the modeling of size effect on the compressive strength of normal concrete with the application of Discrete Element Method (DEM). Test specimens with different size and shape were cast and uniaxial compressive strength test was performed on each sample. Five different concrete mixes were used, all belonging to a different normal strength concrete class (C20/25, C30/37, C35/45, C45/55, and C50/60). The numerical simulations were carried out by using the PFC 5 software, which applies rigid spheres and contacts between them to model the material. DEM modeling of size effect could be advantageous because the development of micro-cracks in the material can be observed and the failure mode can be visualized. The series of experiments were repeated with the model after calibration. The relationship of the parallel bond strength of the contacts and the laboratory compressive strength test was analyzed by aiming to determine a relation between the compressive strength and the bond strength of different sized models. An equation was derived based on Bazant's size effect law to estimate the parallel bond strength of differently sized specimens. The parameters of the equation were optimized based on measurement data using nonlinear least-squares method with SSE (sum of squared errors) objective function. The laboratory test results showed a good agreement with the literature data (compressive strength is decreasing with the increase of the size of the specimen regardless of the shape). The derived estimation models showed strong correlation with the measurement data. The results indicated that the size effect is stronger on concretes with lower strength class due to the higher level of inhomogeneity of the material. It was observed that size effect is more significant on cube specimens than on cylinder samples, which can be caused by the side ratios of the specimens and the size of the purely compressed zone. A limit value for the minimum size of DE model for cubes and cylinder was determined, above which the size effect on compressive strength can be neglected within the investigated size range. The relationship of model size (particle number) and computational time was analyzed and a method to decrease the computational time (number of iterations) of material genesis is proposed.

• Human Ecology Research
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• v.55 no.3
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• pp.289-301
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• 2017

This study was to analyze the effects of the career education program for students with disabilities. The analysis was performed based on two research questions. First, the total effect size on the career program for students with disabilities was considered. Second, the difference of the effect size between the sub-groups regarding dependency variables, types of disabilities, types of schools, number of people, and number of sessions was also included for analysis. For this, the author reviewed a database and analyzed 12 previous studies, presented in five master thesis and seven Korean journals from 2005 to 2015 based on the author's selection criteria. Subsequently, 27 effect size was found. The publication bias was analyzed by Rosenthal's fail-safe N. The overall effect size for all studies on the random effect model was 1.717, which was positive and high in value. Given the heterogeneity among the effect size, the subgroup analysis was conducted, and indicated that the effect size was significantly high when the purpose of the program was related to the student's self-decision ability. The results demonstrated that the programs were specified for students with intellectual disabilities, when the schools were elementary, when the number of students in a group was 1-10, and when program sessions lasted more than 21 times, the effect size was high. Implication for the future research and program implication were discussed on these findings.

• The Mathematical Education
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• v.54 no.4
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• pp.335-350
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• 2015

The purpose of this study was to investigate the effectiveness of the differentiated instruction in mathematics by a meta-analysis. Among the studies conducted for last twenty three years, the relevant 49 research articles were selected, 80 effect sizes were calculated for the cognitive domain and 70 effect sizes for the affective domain. Effect sizes were analyzed with school levels, student level, group organization method such as homogeneous vs. heterogeneous, class transfer and adjusting class sizes for each cognitive domain and affective domain. The results are as the followings: In the cognitive domain, the overall effect size of the differentiated instruction produced a medium effect(effect size=0.68, U3=75.17%). The differentiated instruction showed the highest effect size on elementary school and middle school, mid level students, heterogeneous group, class transfer and not adjusted class size. And in the affective domain, the overall effect size of the differentiated instruction produced a low effect(effect size=0.36, U3=65.36%). The differentiated instruction showed the highest effect size on elementary school, mid level students, and heterogeneous group. Thus the differentiated instruction was proved to be effective in mathematics classes.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.133-139
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• 1963

It is well-known that high temperature hurts the sizing effect of rosin size in paper making, mainly owing to the particle size of rosin-aluminium complex in paper stock. In this experiments, author find, when the temperature of stock rises up. the particle size of rosin-aluminium complex of neutral rosin size increases and the degree of sizing decreases finally. However, the behavior of Bewoid size is quite opposite to former. This result showed that, Bewoid size is suitable in hot summer and neutral rosin size in cold winter for better sizing effect.

• The Journal of Korean Physical Therapy
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• v.32 no.5
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• pp.312-318
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• 2020

Purpose: This study aimed to investigate the evidence that therapeutic horseback riding can improve balance, muscle, ADL, equivalenc, GMFM, gait, emotion with developmental disabilities and neural patients. Methods: To conduct meta-analysis, the search focused on studies that employed therapeutic horseback riding for developmental disabilities and neural patients for which eight databases (KIS, RISS, DBpia, National Assembly Library, Pubmed, Embase, Google scholar and Cochrane Library) were used to extract literature published from 2002 to September 2019. The data were analyzed the RevMan 3.5.3 program. Results: As a result of meta-analysis, therapeutic horseback riding total effect size is 0.552 for children with developmental disabilities and neural patients. And effect size result of according to assessment type variable first, balance effect size is 0.594. Second, muscle activities effect size is 0.425. Third, ADL effect size is 0.430. Fourth, equivalance effect size is 0.640. Fifth, GMFM effect size is 0.482. Sixth, gait effect size is 0.400 and seventh emotion effect size is 0.876. Conclusion: These findings is horseback riding is effective The effect size by outcome was observed to be the effective for children with developmental disabilities and neural patients. and also the horseback riding provided the positive effects of balance, muscle activities, ADL, equivalance, GMFM, gait, emotion for children with developmental disabilities and neural patients. It is hoped that this study will contribute to the development of effective treatments for children with developmental disabilities and neural patients therapeutic horseback riding and the development of study.