• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.625-628
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• 2008

Size-effect correction factors of the flexural test specimens, which had controled cement concrete pavement quality, were investigated and derived to be easily used in field. We couldn't find the size-effects in this size range (10, 12, 15cm) of specimens, which were made of 32mm crushed aggregates, and the theoretical verification was presented by Bazant's equations. Finally, non-dimensional chart for size-effect correction was proposed, covering the relationship between compressive strengths and w/c ratios.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2553-2556
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• 2010

On the basis of a simple modified Poisson-Boltzmann (SMPB) theory, taking into account the finite ionic size, the analytic expression for the effect of ionic size on the diffuse layer potential drop at negative charge densities has been given for the simple 1:1 electrolyte. It is shown that the potential drop across the diffuse layer depends on the size of the ions in the electrolyte. For a given electrolyte concentration and electrode charge density, the diffuse layer potential drop in a small ion system is smaller than that in a large ion system. It is also displayed that the diffuse layer potential drop is always less than the value of the Gouy-Chapman (GC) theory, and the deviation increases as the electrode charge density increases for a given electrolyte concentration. These theoretical results are consistent with the results of the Monte-Carlo simulation [Fawcett and Smagala, Electrochimica Acta 53, 5136 (2008)], which indicates the importance of including steric effects in modeling diffuse layer properties.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.128-136
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• 2017

The purpose of this research is to analyze the effects of smart learning in both general education and fisheries & marine education through meta-analysis. To find the effects size, we had collected 112 studies from graduation theses and journal articles. Followings are the results of the research: (a) Smart learning turns out to be more statistically effective comparing to traditional education. The total effect size of smart learning is .768 and the value of U3 is 61.50%. (b) There is no significant difference between general education and fisheries & marine education in the view of effect size. (c) There is a significant difference in subjects, type of publication, and size of members in experimental group. High school student group has the most effect size of smart learning.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.7 s.238
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• pp.1022-1027
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• 2005

In this study, ball milling process was applied to reduce the particle size of bio-material down to submicron size. The material used was Ibuprofen. The ball milling was performed at low temperature of about $-180^{\circ}C$. The effect of processing conditions (milling time, milling speed) on the particle size was determined. The results showed that the degree of crystallite of Ibuprofen was slightly reduced by the ball milling process. The results also showed that the size of Ibuprofen was significantly reduced by the ball milling process. The effect of milling time was significant within the milling time of six hours while it was small thereafter.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.155-155
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• 1999

Pool boiling critical heat flux (CHF) have been investigated using plate type test sections with different widths (3 cm & 4 cm) and lengths (10 cm, IS cm & 20 cm) under various incli- nation angles. As the inclination angle increases from $0^{\circ}$ (horizontally facing downward plate) to $30^{\circ}$, CHF sharply increases. After that angle, CHF gradually increases with the increase of the inclination angle. There must be a transition angle between $0^{\circ}$ and $30^{\circ}$, at which the CHF increase rate remarkably changes. According to the comparison of present and previous ex- periments, the transition angle may be affected by heater size and increase with the increase of heater size. The size effect of heated surface on CHF is noticeable in the L15 & L20 series and W4 series; however, it seems to be difficult to find the size effect in L10 series and W3 series.

• Journal of Korean Society of Water and Wastewater
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• v.17 no.4
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• pp.528-533
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• 2003

Bubble size is one of the most important parameters affecting DAF (Dissolved-Air-Flotation) process. It is generally known that small bubbles are preferred. However, the fact seems to be based on the particle removal efficiency at contact zone only, without considering separation zone. Besides, the effect of bubble size on the overall DAF process has not been fully investigated yet. Therefore, the effect of bubble size on collision efficiency, collision chances, and surface loading rate is calculated using theoretical models, and the results are discussed in this paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.1B
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• pp.17-24
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• 2008

The effect of the variable packet size on the LRD characteristic of the MMPP traffic model is investigated. When we generate packet traffic for the performance evaluation of IP packet network, MMPP model can be used to generate packet interarrival time. And a random length of packet size from a certain distribution can be assigned to each packet. However, there is a possibility that the variable packet size might change the LRD characteristic of the original MMPP model. In this study, we investigate this possibility. For this purpose the 'refined traffic' is defined, where packet arrival time is generated according to the MMPP model and a random packet length from a specific distribution is assigned to each generated packet. Hurst parameter of the refined traffic is estimated and compared with the original Hurst parameter, which is the input parameter of the MMPP model. We also investigate the effect of the packet size distribution on the queueing performance of the MMPP traffic model and the relationship between the Hurst parameter and queueing performance.

• Advances in concrete construction
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• v.5 no.6
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• pp.613-624
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• 2017

In this paper, an experimental investigation was carried out to study the effect of volume fraction of fiber and maximum aggregate size on mode-I fracture parameters of high strength concrete. Total of 108 beams were tested on loading frame with three point loading, the variables in the high strength concrete beams are aggregate size (20 mm, 16 mm and 10 mm) and volume fraction of fibers (0%, 0.5%, 1% and 1.5%). The fracture parameters like fracture energy, brittleness number and fracture process zone were analyzed by the size effect method (SEM). It was found that fracture energy (Gf) increases with increasing the Maximum aggregate size and also increasing the volume of fibers, brittleness number (${\beta}$) decreases and fracture process zone (CF) increases.

• Environmental and Resource Economics Review
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• v.11 no.4
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• pp.525-556
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• 2002

This paper investigates effect of gasoline price liberalization on price elasticity of gasoline demand. By using a model where a consumer optimizes her gasoline consumption and number of visits to gas station, we derive price elasticity of gasoline demand and its response to variation of size and frequency in price changes. It shows that price elasticity is decreased with increase in the size and frequency when the price rises. Since price liberalization increases the frequency but reduces the size, the effect of the liberalization on the price elasticity may not be determined. However, price liberalization can make the elasticity higher when the size reduction effect exceeds the frequency increase effect, which is consistent with empirical evidence provided by existing studies.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1477-1489
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• 2008

This article deals with the problem of testing whether the effect size in paired study exists. We propose Bayesian hypothesis testing procedures for the effect size in paired study under the noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. So we propose the objective Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Simulation study and a real data example are provided.