• 제목/요약/키워드: Average Effect Size

검색결과 1,102건 처리시간 0.037초

메타 분석을 통한 만성 관절염 환자의 통합 프로그램과 운동 프로그램의 효과 비교 (The Comparison Between the Effects of Integrated Arthritis Self-helf Programs and the Effects of Arthritis Exercise Programs Through Meta-analysis)

  • 오현수;서연옥
    • 대한간호학회지
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    • 제28권4호
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    • pp.941-957
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    • 1998
  • The purpose of this study was to use meta-analysis to analyze result of 17 studies which investigated the effects of integrated programs, and 11 studies which examined the effects of exercise programs on pain, depression, and disability. The 28 studies analyzed in this work were selected from the following sources. MEDLINE Search, bibliographies of related studies, main academic journals of nursing in Korea, and journals on arthritis issues. For the analysis of the data, homogeniety of effect sizes which were calculated based on data in the 28 studies was tested and its average effect size was computed by using meta analysis software package which was developed by Song(1992, 1998). The results can be summarized as follows : 1) Homogeneity tests were conducted on integrated programs on pain. In the prelimiary homogeneity tests on effect size of all 17 studies, no homogeneity was found. When homogeneity tests on the effect size of the remaining 15 studies were performed, excluding two studies which had extremely larger effect size compared to other studies, the 15 studies were found to be homogeneous(Q=16.38, p=.23). The obtained average effect size, D(Mean Standardized Difference Between Means), was .25. When homogeneity tests on effect size on pain was conducted for the excercise programs, effect size for all nine studies were found to be homogeneous (Q=7.42, p=.49) and the average effect size D=.30. Therefore, Hypothesis 1 was rejected from the results, that an average effect size of the integrated programs on pain was not significantely different from that of the exercise programs on pain. 2) Since only two studies investigated the effect of exercise programs on depression, comparison between the average effect size of integrated programs and that of exercise programs on depression could not be conducted, and hypothesis 2 could not be tested. Thereby, only the average effect size of integrated programs on depression was obtained. Eight studies were tested to be positive on the homogeneity of effect sizes(Q=18.31, p=.02) at $\alpha$<.01 and its average effect size was D=.11. 3) For the analysis of integrated program on disability, 13 studies, except for four which had an extremely large effect size compared to the others were found to be homogeneous at $\alpha$<.01 (Q=22.30, p=.04) and the average effect size on disability was D=.16. For analysis of the exercize programs on disability, eight studies, except for one which had an extremely large effect size compared to others, were found to be homo geneous(Q=7.87, p=.34) and the average effect size on disability was D=.60. Therefore, Hypothesis 3 was accepted from the results that an average effect size of exercise programs on disability was significantly larger than that of integrated programs on disability.

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탄성칼슘에 성상이 종이물성에 미치는 영향 (Effect of Particle Shape and Size of Calcium Carbonate on Physical Properties of Paper)

  • 한영림;서영범
    • 펄프종이기술
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    • 제29권1호
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    • pp.7-12
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    • 1997
  • This study was intended to investigate the proper shape and size of calcium carbonate for the improvement of paper properties and its end use performance. We loaded calcium carbonate of various shapes and size in the handsheet and measured their physical and optical properties. Results obtained from the study are summarized as follows : 1. Due to different particle shapes and sizes, precipitated calcium carbonate (PCC) contributed greater to bulk improvement than ground calcium carbonate (GCC). Scalenohedral form of PCC produced the bulkiest sheet, GCC made the sheet bulkier as average particle size increases. 2. Tensile strength increased as average particle size was increasing. GCC kept tensile strength more effectively than PCC. The effect of particle size on tensile strength was much more pronounced as filler addition level was increasing. 3. Over the average particle size of 6.99$\mu$m, GCC gave much higher burst strength and internal bond than PCC did. In the filler levels of 20% and 30%, GCC by using bigger size fillers showed 50~100% improvement in some cases than PCC at the same filler content. 4. Tear strength increased as average particle size was increasing. At the filler level of 30%, PCC decreased tear greatly. 5. Over the average particle size of 13.56$\mu$m, GCC kept bending stiffness greater than PCC. Due to its shape, Scalenohedral form of PCC showed higher stiffness than others at the same particle size. 6. Cubic and acicular form of PCC improved light scattering coefficient very effectively. Light scattering coefficient of GCC decreased as average particle size increased. 7. Both of particle shape and size of filler were important factor in developing optical properties and bending stiffness. Particle size was the only important factor in developing other strength properties

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심폐소생술 교육 효과에 대한 메타분석 연구 (A Meta-analysis of the effects of cardiopulmonary resuscitation training)

  • 유순규;이지은
    • 한국응급구조학회지
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    • 제21권1호
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    • pp.17-44
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    • 2017
  • Purpose: This study aimed to identify the effects of cardiopulmonary resuscitation (CPR) training using a meta-analysis by effect size. Methods: The effect sizes for each variable and the overall effect size for the collected data were identified. The homogeneity verification of the effect size and the difference among the average effect sizes for each mediation variable were determined. Results: The overall average effect size for CPR training was 1.747. Homogeneity verification of the overall effect size was a Q-value of 3716.962, which was statistically significant (p=.000) when${\alpha}=.05$. CPR training showed statistically significant differences depending on age (p=.002), sex (p=.006), number of trainees (p=.000), research design (p=.000), training method (p=.027), and practical training tools (p=.000). Conclusion: CPR training can effectively improve knowledge, skills, and attitudes about CPR. The results of this meta-analysis contribute to the development of more effective educational guidelines for future CPR training and the advancement of the CPR education field.

Effect of Nozzle Tip Size on the Fabrication of Nano-Sized Nickel Oxide Powder by Spray Pyrolysis Process

  • Kim, Donghee;Yu, Jaekeun
    • 한국재료학회지
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    • 제23권9호
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    • pp.489-494
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    • 2013
  • In this study, by using nickel chloride solution as a raw material, a nano-sized nickel oxide powder with an average particle size below 50 nm was produced by spray pyrolysis reaction. A spray pyrolysis system was specially designed and built for this study. The influence of nozzle tip size on the properties of the produced powder was examined. When the nozzle tip size was 1 mm, the particle size distribution was more uniform than when other nozzle tip sizes were used and the average particle size of the powder was about 15 nm. When the nozzle tip size increases to 2 mm, the average particle size increases to roughly 20 nm, and the particle size distribution becomes more uneven. When the tip size increases to 3 mm, particles with an average size of 25 nm and equal to or less than 10 nm coexist and the particle size distribution becomes much more uneven. When the tip size increases to 5 mm, large particles with average size of 50 nm partially exist, mostly consisting of minute particles with average sizes in the range of 15~25 nm. When the tip size increases from 1 mm to 2 mm, the XRD peak intensities greatly increase while the specific surface area decreases. When the tip size increases to 3 mm, the XRD peak intensities decrease while the specific surface area increases. When the tip size increases to 5 mm, the XRD peak intensities increase again while the specific surface area decreases.

An experimental study of scale effect on the shear behavior of rock joints

  • Lee Tae-Jin;Lee Sang-Geun;Lee Chung-In;Hwang Dae-Jin
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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    • pp.156-161
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    • 2003
  • Mechanical behavior of rock joints usually can be characterized by small-scale laboratory shear tests due to economical and technical limitations, but their applicability to the behaviour of rock mass has been always questioned by a number of researchers because of scale effect. Though there have been several researches regarding the scale effect, it has been a controversial problem how to apply the result of small-scale laboratory shear test directly to field design from different conclusions among researchers. In order to grasp the trend of scale effect of shear behavior, a series of direct shear tests on replicas of natural rock joint surfaces made of gypsum cement with different size and roughness were conducted and analyzed. Result showed that as the size of the specimen increased, average peak shear displacement increased, but average shear stiffness and average peak dilation angle decreased. As for the dependency of scale on shear strength, the degree of scale effect was dependent on normal stress and roughness of rock joint. For the condition of low normal stress and high roughness, decrease of average peak shear strength with increasing size of joint was evident.

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초음파법에 의한 저탄소강의 페라이트 결정립 크기 측정 (Measurement of Ferrite Grain Size by Ultrasonic Method in Low Carbon Steel)

  • 홍순택;권숙인;주웅용
    • 열처리공학회지
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    • 제12권2호
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    • pp.157-165
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    • 1999
  • Grain size of steels is one of the most important parameters which influence yield strength and fracture toughness. Ultrasonic wave propagating in polycrystalline materials is mostly attenuated by scattering at grain boundary. Effect of ultrasonic attenuation on average ferrite grain size of carbon steels with tensile strength $40{\sim}60kgf/mm^2$ consisting of multi phases such as ferrite + pearlite and ferrite + pearlite + bainite was evaluated. The attenuation of these steels rapidly increased with average ferrite grain diameter. Average ferrite grain diameter ($D_{av}$, ${\mu}m$) could be expressed as $1.79+22.97*a^{1/2.03}$, where a is attenuation with unit of nepers/cm. From this study, it was confirmed that nondestructive ultrasonic method could be used in measuring average ferrite grain size indirectly.

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분무열분해공정에 의한 인듐 산화물 나노 분말 제조에 미치는 반응인자들의 영향 (Effect of Reaction Factors on the Fabrication of Nano-Sized Indium Oxide Powder by Spray Pyrolysis Process)

  • 유재근
    • 한국분말재료학회지
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    • 제11권6호
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    • pp.493-502
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    • 2004
  • In this study, nano-sized indium oxide powder with the average particle size below 100 nm is fab-ricated from the indium chloride solution by the spray pyrolysis process. The effects of the reaction temperature, the concentration of raw material solution and the inlet speed of solution on the properties of powder were studied. As the reaction temperature increased from 850 to $1000^{\circ}C$, the average particle size of produced powder increased from 30 to 100 nm, and microstructure became more solid, the particle size distribution was more irregular, the intensity of a XRD peak increased and specific surface area decreased. As the indium concentration of the raw material solution increased from 40 to 350 g/l, the average particle size of the powder gradually increased from 20 to 60 nm, yet the particle size distribution appeared more irregular, the intensity of a XRD peak increased and spe-cific surface area decreased. As the inlet speed of solution increased from 2 to 5 cc/min., the average particle size of the powder decreased and the particle size distribution became more homogeneous. In case of the inlet speed of 10 cc/min, the average particle size was larger and the particle size distribution was much irregular compared with the inlet speed of 5 cc/min. As the inlet speed of solution was 50 cc/min, the average particle size was smaller and microstructure of the powder was less solid compared with the inlet speed of 10 cc/min. The intensity of a XRD peak and the variation of specific area of the powder had the same tendency with the variation of the average par-ticle size.

Effects of Ultra-high Pressure Homogenization on the Emulsifying Properties of Whey Protein Isolates under Various pH

  • Lee, Sang-Ho;Subirade, Muriel;Paquin, Paul
    • Food Science and Biotechnology
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    • 제17권2호
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    • pp.324-329
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    • 2008
  • The effect of ultra-high pressure homogenization on the emulsifying properties of whey protein was investigated in a model emulsion made with whey protein isolate and soya oil under various pH. The emulsifying properties, the average diameter of the oil droplets ($d_{vs}$), and the protein load, were measured for each emulsion produced at different homogenization pressures (50 to 200 MPa) and pH values (4.6 to 8.0). According to the results of variance analysis and response surface, the pH had more influence on oil droplet size and protein load than homogenization pressure. The model equations, which were obtained by response surface analysis, show that pH and homogenization pressure had the major effect on oil droplet size and protein load. Higher homogenization pressure decreased the average droplet size and the protein load. Homogenization at high pressure, as opposed to low pressure, causes no overprocessing, but the effect was pH-dependent. The average diameter of the oil droplets increased slightly by decreasing the pH from 8.0 to 6.5 and then increased dramatically toward the isoelectric point of whey protein (i.e., at pH 4.6). Moreover associated droplets were found at acidic pH and their size was increased at high temperature.

분무열분해공정에 의한 니켈 페라이트 나노 분말 제조에 미치는 반응인자들의 영향 (Effect of Reaction Factors on the Fabrication of Nano-Sized Ni-ferrite Powder by Spray Pyrolysis Process)

  • 유재근;서상기;박시현;한정수
    • 한국분말재료학회지
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    • 제11권3호
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    • pp.202-209
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    • 2004
  • In this study, nano-sized powder of Ni-ferrite was fabricated by spray pyrolysis process using the Fe-Ni complex waste acid solution generated during the shadow mask processing. The average particle size of the produced powder was below 100 nm. The effects of the reaction temperature, the inlet speed of solution and the air pressure on the properties of powder were studied. As the reaction temperature increased from 80$0^{\circ}C$ to 110$0^{\circ}C$, the average particle size of the powder increased from 40 nm to 100 nm, the fraction of the Ni-ferrite phase was also on the rise, and the surface area of the powder was greatly reduced. As the inlet speed of solution increased from 2 cc/min. to 10 cc/min., the average particle size of the powder greatly increased, and the fraction of the Ni-ferrite phase was on the rise. As the inlet speed of solution increased to 100 cc/min., the average particle size of the powder decreased slightly and the distribution of the particle size appeared more irregular. Along with the increase of the inlet speed of solution more than 10 cc/min., the fraction of the Ni-ferrite phase was decreased. As the air pressure increased up to 1 $kg/cm^2, the average particle size of the powder and the fraction of the Ni-ferrite phase was almost constant. In case of 3 $kg/cm^2 air pressure, the average particle size of the powder and the fraction of the Ni-ferrite phase remarkably decreased.

패밀리 레스토랑에서 고객의 동반인원수가 수익에 미치는 영향에 관한 연구 (The Impact of Customer's Party Size on Restaurant Revenue)

  • 조미희;이경희
    • 한국식생활문화학회지
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    • 제26권6호
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    • pp.692-697
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    • 2011
  • Restaurant managers seeking to maximize revenue should look carefully at how long their tables are occupied and how much the average diner spends. This study examined the effect of the customer's party size on restaurant revenue. The dining periods were divided into 2 types (lunch vs. dinner/weekdays vs. weekends), which were combined to show the average spending per minute (SPM), to determine if the dining periods have measurable effects on the dining duration and average bill. The results show that the dining duration for dinner was much longer than that for lunch and there was no significant difference in dining duration between weekdays and weekends. On the other hand, customers in larger parties at lunch time had a higher SPM than those in smaller parties. A larger customer party size was associated with a longer dining duration for dinner and on weekdays. During all operating periods (lunch, dinner, weekdays, weekends), the party size had a significantly positive effect on the mean spending per minute. For restaurant managers, these findings suggest opportunities to increase revenue and adopt revenue management strategies.