• Title/Summary/Keyword: Size effect

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Effects of Treadmill Exercise on Pulmonary Function and Gait Capacity in Stroke Patients : A meta-analysis (트레드밀 운동이 뇌졸중 환자의 폐기능과 보행능력에 미치는 효과 : 메타분석)

  • Cho, Sunghyoun;Choi, Kibok
    • Journal of The Korean Society of Integrative Medicine
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    • v.8 no.2
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    • pp.169-185
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    • 2020
  • Purpose : This study aimed to conduct a comprehensive meta-analysis to evaluate the effect size for pulmonary function and gait capacity of treadmill exercise in stroke patients. In addition, we aimed to examine the current status of treadmill interventions and compare the effect sizes of treadmill training to provide evidence-based practice for future development and application. Methods : The meta-analysis study was conducted using research articles that applied treadmill exercise to stroke patients and were published between January 2005 and February 2020. For a systematic meta-analysis, we conducted a search using the PICOS framework and selected 25 domestic stroke- and treadmill-related studies. The Comprehensive Meta-Analysis program was used to calculate the effect sizes for lung function and gait capacity (6-minute walk test and 10 m walk test). As Cohen's d has a tendency to overestimate the effect size, we used Hedge's g to increase the accuracy in computing the effect size. Results : Based on the results of the meta-analysis, the total effect size of treadmill exercise was 0.535, which was statistically significant, with a medium effect size (p<0.05). The effects of treadmill exercise in stroke patients were divided into dependent variables, namely pulmonary function (0.372) and gait capacity (0.584). In addition, for gait capacity, the effect sizes were evaluated for both the 6-minute walk test (0.756) and the 10 m walk test (0.514). Conclusion : This study provides objective evidence of the effectiveness of treadmill-based gait training programs. We hope that the results of this study will help support the development and implementation of treadmill-based gait training in stroke patients. Treadmill training is expected to improve not only pulmonary function, but also the gait capacity of stroke patients. Long-term investigations on the effects of treadmill training in stroke patients are necessary.

A Meta-Analysis on the Effect of Music Intervention on the Anxiety of Children and Adolescents (음악중재가 아동 및 청소년의 불안에 미치는 효과에 대한 메타분석)

  • Bae, Ik-lyul;Kim, Min-woong
    • Stress
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    • v.25 no.2
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    • pp.86-92
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    • 2017
  • The present study investigated the effect of music intervention on the anxiety of children and adolescents using meta-analysis, and the specific research purposes were as follows. The targets of the present study were previous studies analyzed the effect of music intervention on anxiety collected the final 28 theses for academic degrees and five scholarly journal articles were used in the analysis. To examine the publication bias of the studies used in the analysis, funnel plot and fail-safe N were verified, and found the publication bias was not significant enough to influence the present study. The homogeneity test showed that the effect size was heterogeneous, and accordingly, a random effect model analysis was carried out and the overall effect size was found to be -1.034. The analysis on the difference in the effect showed that the effect size varied according to subject classification and intervention location for categorical variables and size for continuous variables.

Effect of pH in 3.5% NaCl aqueous solution and ferrite grain size on corrosion fatigue fracture of dual phase steel (複合組織鋼의 부식피로파괴에 미치는 3.5% NaCl水溶液의 pH와 母相粒徑의 效果)

  • 오세욱;강호민
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.11 no.6
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    • pp.867-876
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    • 1987
  • Corrosion fatigue fracture with change in the grain size of M.E.F. dual phase steel is investigated in 3.5% NaCI aqueous solution at pH 2, 4, 6, 9, and 11. Generally speaking, decrease in corrosion fatigue life is strongly dependent on decrease in pH and slightly on the grain size. For the B material with the big grain size, the fatigue life is small due to its large reduction ratio of corrosion fatigue life. The influence of grain size on the reduction ratio of corrosion fatigue life is large at pH 11-6. Whi9le at pH 4-2 the reduction ratio of corrosion fatigue life only depends on the corrosion effect. The larger grain size and the lass pH result in the greater influence on corrosion fatigue crack propagation rate. As pH decreases, the plateau portion in the crack propagation rate curves of the B material are distinct. Crack propagation rate curves become slow down at high .DELTA.K range because crack closure effect by minute corrosion products inside crack causes the oxidation corrosion action less effective for a certain period of time. In A material with small grain size, fatigue life is increased in proportion with increase of martensite intergranular which brings forth restraining the crack propagation decreases crack propagation rate. Corrosion pit which is created in the surface of specimen is found at pH 6,4 and 2 which is noticeable and the unevenness of the surface of the specimen becomes severe as pH decreases. The unevenness of corrosion fatigue fracture surface is severe as the effect of pH increases i.e. as pH decreases. In proportion with increase in the grain size and decrease in pH, the aspect of brittle fracture becomes evident.

Two-stage Sampling for Estimation of Prevalence of Bovine Tuberculosis (이단계표본추출을 이용한 소결핵병 유병률 추정)

  • Pak, Son-Il
    • Journal of Veterinary Clinics
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    • v.28 no.4
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    • pp.422-426
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    • 2011
  • For a national survey in which wide geographic region or an entire country is targeted, multi-stage sampling approach is widely used to overcome the problem of simple random sampling, to consider both herd- and animallevel factors associated with disease occurrence, and to adjust clustering effect of disease in the population in the calculation of sample size. The aim of this study was to establish sample size for estimating bovine tuberculosis (TB) in Korea using stratified two-stage sampling design. The sample size was determined by taking into account the possible clustering of TB-infected animals on individual herds to increase the reliability of survey results. In this study, the country was stratified into nine provinces (administrative unit) and herd, the primary sampling unit, was considered as a cluster. For all analyses, design effect of 2, between-cluster prevalence of 50% to yield maximum sample size, and mean herd size of 65 were assumed due to lack of information available. Using a two-stage sampling scheme, the number of cattle sampled per herd was 65 cattle, regardless of confidence level, prevalence, and mean herd size examined. Number of clusters to be sampled at a 95% level of confidence was estimated to be 296, 74, 33, 19, 12, and 9 for desired precision of 0.01, 0.02, 0.03, 0.04, 0.05, and 0.06, respectively. Therefore, the total sample size with a 95% confidence level was 172,872, 43,218, 19,224, 10,818, 6,930, and 4,806 for desired precision ranging from 0.01 to 0.06. The sample size was increased with desired precision and design effect. In a situation where the number of cattle sampled per herd is fixed ranging from 5 to 40 with a 5-head interval, total sample size with a 95% confidence level was estimated to be 6,480, 10,080, 13,770, 17,280, 20.925, 24,570, 28,350, and 31,680, respectively. The percent increase in total sample size resulting from the use of intra-cluster correlation coefficient of 0.3 was 22.2, 32.1, 36.3, 39.6, 41.9, 42.9, 42,2, and 44.3%, respectively in comparison to the use of coefficient of 0.2.

An Integrative Review and Meta-analysis of Oncology Nursing Research : 1985-1997.2 (국내 암환자와 관련된 연구논문의 메타분석 - 실험연구를 중심으로 -)

  • 임선옥;홍은영
    • Journal of Korean Academy of Nursing
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    • v.27 no.4
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    • pp.857-870
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    • 1997
  • The purposes of this study were to describe 12 years of patient-related oncology nursing research in Korea, identifying various nursing interventions, and assesing the effectiveness of the interventions, through analysis and synthesis of the accumulated research papers. One hundred and seventy-nine studies were selected for this study and these were mostly descriptive in design (69.2%). Of the 179 studies, 25 met the criteria for meta-analytic treatment. Twenty-five experimental studies were found in theses and dissertations (68%), 92% used convenience sample, and the median sample size was 40. Subjects were predominantly in treatment and rehabilitation (76%). Most studies(68%) were not derived from a theory base, with only 8% reporting use of a nursing theory. Results of the meta-analysis are as follows. The effect size of the nursing intervention type was found to be significantly effective. The standardized mean difference ranged from a high positive of 2.55 to a low negative of -0.22. Direct personal nursing intervention method was more effective than indirect group method. Two nursing intervention methods were more effective than one. The greatest effect size was thyxical intervention. The greatest mean effect size was scalp hypothermia technique. Teaching was a frequent intervention after 1990, although a wide range of treatments were studied. Effect size of intervention for symptom management was largest in relieving pain. Effective intervention method for relieving anxiety was exercise.

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Comparative Pattern Analysis and the Fitness Evaluation of Brassieres (국내.외 브래지어의 패턴비교분석 및 착의평가 연구)

  • Suh, Chu-Yeon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.34 no.4
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    • pp.673-685
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    • 2010
  • This study evaluates the fitness of brassieres through size measurement, comparative pattern analysis, cross section map analysis, 3-D shape analysis number, and fitness evaluation with a focus on domestic and overseas brands. Experimental brassieres were selected as mold brassieres of 3/4 cup in 75A size that is considered a popular design. Brands of selected brassiere were 2 domestic brands (A, B), 1 licensed brand (C), and 2 overseas brands (D, E). Subjects were 8 women in their early 20's. Data were analyzed by descriptive statistics, analysis of variance, reliability analysis, and factor analysis. The results were as follows; the size and pattern of brassieres showed a difference by each brand even though brassieres are the same design. In the wearing effect of brassieres, overseas brand brassieres played a major role in the breast-up effect, but they were not appropriate for the somatotype of Korean women. Domestic brand brassieres showed the volume-up effect, that was confirmed by the increasing bust circumference, bust depth when subjects wore it. In addition, the licensed brand brassieres showed the correction effect of body shape. Therefore, when purchasing a brassiere, the most important condition is to consider the individual characteristics of the somatotype. The results of factor analysis through a functional evaluation show that wearing satisfaction, size satisfaction, and the position of the bust point were important factors for fitness satisfaction and purchase.

A study of detector size effect using Monte Carlo simulation

  • Park, Kwang-Yl;Yi, Byong-Yong;Vahc, Young W.
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2004.11a
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    • pp.36-38
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    • 2004
  • The detector size effect due to the spatial response of defectors is one critical source of inaccuracy in clinical dosimetry and has been a subject of numerous studies. Conventionally, the detector response kernel contains all of the influence that the detector size has on the measured beam profile. Various analytic models for this kernel have been proposed and studied in theoretical and experimental works. Here, we use a method to determine detector response kernel simply by using Monte Carlo simulation and convolution theory. Based on this numerical method and DOSIMETER, an EGS4 Monte Carlo code, the detector response for a Farmer type ion chamber embedded in water phantom is obtained. There exists characteristic difference in the simulated chamber readings between one with carbon graphite wall and the other with Acrylic wail. Using the obtained response and the convolution theory, we are planning to derive the detector response kernel numerically and remove detector size effect from measurements for 6MV, 10${\times}$l0cm2 and 0.5${\times}$10 cm2 photon beam.

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The Effect of the Project Managers' IT Competency and Managerial Competency on the Success of SI Projects : Focusing on the Moderating Effect of Project Size (SI 프로젝트에 있어서 프로젝트 관리자의 정보화 역량과 관리 역량이 프로젝트 성공도에 미치는 영향에 대한 연구 : 프로젝트 규모의 조절효과를 중심으로)

  • Lee, Choong C.;Park, Joo-Yeon;Choi, Jeong-Hoon
    • The Journal of Information Systems
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    • v.21 no.4
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    • pp.31-54
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    • 2012
  • Information Systems have played a strategic role in achieving business goal and become an essential tool in today's business environment. Thus, the number of developing SI project has increased and it becomes complex and sophisticated. It is known that project manager's leadership could lead the project success. In this study, project manager's competencies are divided into two types, information competency(information-oriented mind, information utilization competency, information development competency) and managerial competency(project management, human relationship, project expertise. The purpose of this study is to examine the effect of information competency and managerial competency on the SI project success and to find out the moderating effect of project size. The result of this study reveals that information utilization competency, project management competency and human relationship have a strong relationship with both customers and suppliers side of projet success. Moreover, the relationship between managers' competencies and project success is shown to be different by project size. The result of this study implies that each managers' competencies has to be developed and applied according to project's complexity and size.

Reflectance Characteristics of Al-Si based Alloys according to Powder Size and Composition (Al-Si계 합금의 분말 크기 및 조성에 따른 반사율 변화 특성)

  • Choi, Gwang Mook;Chae, Hong Jun
    • Journal of Powder Materials
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    • v.26 no.1
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    • pp.22-27
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    • 2019
  • In this study, the effects of powder size and composition on the reflectance of Al-Si based alloys are presented. First, the reflectance of Al-Si bulk and powder are analyzed to confirm the effect of powder size. Results show that the bulk has a higher reflectance than that of powder because the bulk has lower surface defects. In addition, the larger the particle size, the higher is the reflectance because the interparticle space decreases. Second, the effect of composition on the reflectance by the changing composition of Al-Si-Mg is confirmed. Consequently, the reflectance of the alloy decreases with the addition of Si and Mg because dendrite Si and $Mg_2Si$ are formed, and these have lower reflectance than pure Al. Finally, the reflectance of the alloy is due to the scattering of free electrons, which is closely related to electrical conductivity. Measurements of the electrical conductivity based on the composition of the Al-Si-Mg alloy confirm the same tendency as the reflectance.

A damage model predicting moderate temperature and size effects on concrete in compression

  • Hassine, Wiem Ben;Loukil, Marwa;Limam, Oualid
    • Computers and Concrete
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    • v.23 no.5
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    • pp.321-327
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    • 2019
  • Experimental isotherm compressive tests show that concrete behaviour is dependent on temperature. The aim of such tests is to reproduce how concrete will behave under environmental changes within a moderate range of temperature. In this paper, a novel constitutive elastic damage behaviour law is proposed based on a free energy with an apparent damage depending on temperature. The proposed constitutive behaviour leads to classical theory of thermo-elasticity at small strains. Fixed elastic mechanical characteristics and fixed evolution law of damage independent of temperature and the material volume element size are considered. This approach is applied to compressive tests. The model predicts compressive strength and secant modulus of elasticity decrease as temperature increases. A power scaling law is assumed for specific entropy as function of the specimen size which leads to a volume size effect on the stress-strain compressive behaviour. The proposed model reproduces theoretical and experimental results from literature for tempertaures ranging between $20^{\circ}C$ and $70^{\circ}C$. The effect of the difference in the coefficient of thermal expansion between the mortar and coarse aggregates is also considered which gives a better agreement with FIB recommendations. It is shown that this effect is of a second order in the considered moderate range of temperature.