• Title/Summary/Keyword: size effect model

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A Study on the Characteristics of Stress Transfer around Cavern due to Cavern size and Rock Joint Orientation by Laboratory Model Test (모형실험을 통한 공동규모와 절리 방향성에 따른 공동배면의 응력전이 특성에 대한 연구)

  • Kim, Sang-Hwan;Shin, Beom-Seok
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.595-606
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    • 2009
  • This paper presents the characteristics of stress transfer around carven due to cavern size and rock joint properties by laboratory model test. In order to perform this study, eight different scaled model tests were carried out according to excavation stage. The limited numerical analysis were also performed to verify the model test results. The amount of stress transfer around the cavern is increased and then decreased by longitudinal arching effect according to tunnel excavation. It is founded that the stress developed around the cavern during excavation is increased when the cavern size and joint orientation are increased. It is also investigated that shear behaviour (such as stress, deformation) developed around cavern is considerably depended on the characteristic of fill material, dip and direction of joints. It is suggested that the behaviour will be verified throughout the 3D numerical prediction.

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The effects of non-uniform droplets distribution on the characteristics of group combustion for liquid fuel droplets cloud (비균일 액적분포가 액적군의 집단연소 특성에 미치는 영향)

  • 김호영;전철균
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.11 no.3
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    • pp.479-487
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    • 1987
  • In order to predict the effects of droplets distributions such as number density and droplets size on group combustion characteristics and flame structure for liquid fuel sprays, modifications of group combustions model were made by changing the droplets distributions from uniform to non-uniform. Various droplets distribution models were adopted in this analysis to examine the effect of number density distribution on combustion characteristics and the difference between uniform and non-uniform droplets size distributions for a spherical droplets cloud. As results of present study, hollow droplets could with outer concentrating distribution has shorter total combustion time compare with the case of solid droplets cloud with inner concentrating distribution. Uniform droplets size distribution model predicts the shorter total combustion time compare with non-uniform droplets size distribution model, and the uniform droplets size distribution model may be used to predict the total combustion time for the droplets cloud containing larger initial size of droplets.

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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    • v.17 no.2
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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.

Analysis of Thermo Environment Change by Introduction of Indoor Water Space (실내 수공간 도입에 따른 온열 환경 변화 분석)

  • Oh, Sang Mok;Oh, Se Gyu
    • KIEAE Journal
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    • v.12 no.3
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    • pp.53-60
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    • 2012
  • This research is an illustrative research to verify the thermo environmental change created after introduction of indoor pond through abridged model test and simulation analysis. Especially, temperature and comfort level are analyzed by adjusting factors like size of water space, distance length, and location. Summary of the research is as follows. First, the most effective size of water space is 7% of the indoor size, from southern side. Temperature reduction effect is about $1.6^{\circ}C$(5.5%), and for the comfort level, it is found that pmv index increases 8%. Second, based on the simulation of distance length with the sphere, it is more effective as it is close to the surface. If distance length is more than 0.5m, there is no effect on reduction of temperature and comfort level of indoor environment. Lastly, for the analysis by location of the introduced water space, simulation is undertaken by dividing the water space (14% of the indoor size) with front, side, rear and center types. Temperature reduction effect is found to be : front type ($-1.53^{\circ}C$), side type ($-0.82^{\circ}C$), rear type ($-0.44^{\circ}C$), center type ($-0.28^{\circ}C$), respectively. The indoor environment change data by introduction of water space, found in this research, is at initial phase, but it is deemed to be a basic data to refer when planning actual water space.

The Relationship Between Non-Interest Revenue and Sustainable Growth Rate: A Case Study of Commercial Banks in Jordan

  • AL-SLEHAT, Zaher Abdel Fattah;ALTAMEEMI, Arshed Fouad
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.5
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    • pp.99-108
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    • 2021
  • As expansion of interest income business faces several limitations, non-interest revenue can play a vital role in increasing the net profit margin and the productivity of the assets to sustain the growth rate. This study aims to analyze the Effect level (partial or total) of a bank's size on the relationship between non-interest revenue and the sustainable growth rate of Jordanian commercial banks. Baron and Kenny's methodology (1986) was adopted to test and analyze the effect of non-interest revenue: including the bank's size, on the sustainable growth rate during the period from 2008-2019. Data collection was done for thirteen commercial banks which constituted 100% of the study population. Testing four hypotheses by using Amos program and a regression model to diagnose the partial and total effect of size. Findings indicate that there is a nonlinear relationship between Non-IR and SGR due to the total effect of bank size on the sustainable growth rate. The results of this study is expected to enable the banks to diversify their revenue to support financial performance towards healthy growth without facing additional financial problems. This study adopted a different methodology from the prior efforts, by using the mediation effect role to verify the effect of non-interest revenue.

A Meta-Analysis on the Correlation between Job Satisfaction, Turnover Intention and Organizational Commitment among Nurses

  • Lee, Hong-Ki;Myoun, Sungmin
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.4
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    • pp.115-122
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    • 2017
  • The purpose of this study was to evaluate the effect of job satisfaction on turnover intention and organizational commitment in nurses through a systematic literature review and meta-analysis. For the study purpose, 26 studies were selected through a systematic process of using several databases and used to estimate the effect size of correlation between 3 variables. Meta-analysis was applied by usingcrandom effects model, and effect sizes on three types were calculated. Results are as follows. First, the effect size of correlation between job satisfaction and turnover intention is -.58. Second, the effect size of correlation between job satisfaction and organizational commitment is .77. Third, for the organizational commitment and turnover intention relationship, the effect of correlation is -0.68. Furthermore, publication bias analysis were assessed the results by using the funnel plot, Egger's regression test, fail-safe N, and trim-and-fill test. Based on these results, implications for the study were discussed.

Effective mechanical properties of micro/nano-scale porous materials considering surface effects

  • Jeong, Joonho;Cho, Maenghyo;Choi, Jinbok
    • Interaction and multiscale mechanics
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    • v.4 no.2
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    • pp.107-122
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    • 2011
  • Mechanical behavior in nano-sized structures differs from those in macro sized structures due to surface effect. As the ratio of surface to volume increases, surface effect is not negligible and causes size-dependent mechanical behavior. In order to identify this size effect, atomistic simulations are required; however, it has many limitations because too much computational resource and time are needed. To overcome the restrictions of the atomistic simulations and graft the well-established continuum theories, the continuum model considering surface effect, which is based on the bridging technique between atomistic and continuum simulations, is introduced. Because it reflects the size effect, it is possible to carry out a variety of analysis which is intractable in the atomistic simulations. As a part of the application examples, the homogenization method is applied to micro/nano thin films with porosity and the homogenized elastic coefficients of the nano scale thickness porous films are computed in this paper.

The Effect of Self-efficacy for the Size Recommendation Services on Usage Intention through Perceived Ease of Use and Perceived Usefulness -Focusing on the Moderating Effect of the Filtering Types- (사이즈 추천 서비스에 대한 자기효능감이 지각된 사용용 이성과 지각된 유용성을 매개로 사용의도에 미치는 영향 -필터링 유형의 조절효과를 중심으로-)

  • Sangwoo Seo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.48 no.4
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    • pp.688-706
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    • 2024
  • This study investigated the effect of self-efficacy on the usage intention of the size recommendation services, exploring the mediating roles of perceived ease of use and perceived usefulness. Moreover, it examined the moderating effects of filtering types on these relationships. Data were collected from 200 participants between December 11 and 13, 2023, using virtual scenarios and stimuli. Mediating and moderating effect analysis were performed using a process macro. As a result of path analysis and indirect effect analysis between individual variables, it was confirmed that the direct effect of self-efficacy for the size recommendation services on usage intention, and the indirect effect on usage intention through perceived ease of use and perceived usefulness were significant. Furthermore, as a result of the moderating effect analysis, it was found that the moderating effect of the filtering types was significant in the relationship between self-efficacy and perceived ease of use, between perceived ease of use and perceived usefulness, and between self-efficacy and usage intention.

Along-wind simplified analysis of wind turbines through a coupled blade-tower model

  • Spagnoli, Andrea;Montanari, Lorenzo
    • Wind and Structures
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    • v.17 no.6
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    • pp.589-608
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    • 2013
  • A model is proposed to analyse the along-wind dynamic response of upwind turbines with horizontal axis under service wind conditions. The model takes into account the dynamic coupling effect between rotor blades and supporting tower. The wind speed field is decomposed into a mean component, accounting for the well-known wind shear effect, and a fluctuating component, treated through a spectral approach. Accordingly, the so-called rotationally sampled spectra are introduced for the blades to account for the effect of their rotating motion. Wind forces acting on the rotor blades are calculated according to the blade element momentum model. The tower shadow effect is also included in the present model. Two examples of a large and medium size wind turbines are modelled, and their dynamic response is analysed and compared with the results of a conventional static analysis.

A study on the prediction of the mechanical properties of nanoparticulate composites using homogenization method with effect interface concept (유효계면 모델과 균질화 기법을 이용한 나노입자 복합재의 역학적 물성 예측에 관한 연구)

  • Jang, Seong-Min;Yang, Seung-Hwa;Yu, Su-Young;Cho, Maeng-Hyo
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.684-689
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    • 2008
  • In this study, homogenization method combined with the effective interface model for the characterization of properties of the nanoparticulate composites is developed. In order to characterize particle size effect of nanocomposites, effective interface model has been developed. The application range of analytical micromechanics approach is limited because a simple analytical approach is valid only for simple and uniform geometry of fiber particles. Therefore this study focuses on the analysis of mechanical properties of the effect interface through the continuum homogenization method instead of using analytical micromechanics approach. Using the homogenization method, elastic stiffness properties of the effective interface are numerically evaluated and compared with the analytically obtained micromechanics solutions. The suggested homogenization method is expected to be applied to optimization problems for nanocomposite design.

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