• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.705-710
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• 2003

In this study, to confirm the diffusion coefficient of chloride ion is affected by the concentration of NaCl solution, capacity of voltage, time of an electric current, the diffusion coefficient of chloride ion in concrete was investigated through an electrochemical accelerated test. and the results of these test were compared with the diffusion coefficient of chloride ion by test of sodium chloride solution digestion. As the results of this study, the diffusion coefficient of chloride ion wasn't affected by the concentration of NaCl solution, capacity of voltage, time of an electric current within the range of this study and was similar to the diffusion coefficient of chloride ion by test of sodium chloride solution digestion.

• Journal of Technology Innovation
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• v.13 no.1
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• pp.113-139
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• 2005

The purpose of this study is to analyse the diffusion process of personal computer (PC) in Korea during the 1990's. To achieve the goal, five research steps have been done such as the literature survey of diffusion theory, set-up of theoretic equilibrium model of supply and demand, derivation of an equilibrium path using Hamiltonian, and empirical analysis. The empirical analysis has been performed based on that equilibrium path. The results can be summarized as follows : First, technological attribute of diffusing product influences the diffusion speed of Product. It has been proven that the size of the network has a significant effect on the diffusion of PC in empirical study Second, supply factors have an important role in the diffusion process. According to the empirical analysis, decreasing cost of production as a result of technological advance promotes the speed of diffusion. This point seems to be manifest theoretically, but existing empirical models have not included supply factors explicitly, Third, it has been found out that expectation of decreasing cost would influence the speed of diffusion negatively as expected ex ante. Theoretically this result is supported by arbitrage condition of purchasing timing.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.12
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• pp.1009-1016
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• 2007

Numerical study on preferential diffusion effects in flame structure in $CH_4-H_2$ diffusion flames is conducted with detailed chemistry. Comparison of flame structures with mixture-averaged species diffusion and suppression of the diffusivities of $H_2$ and H was made. Discernible differences in flame structures are displayed with three species diffusion models. The behaviors of maximum flame temperatures with those species diffusion models are not explained by scalar dissipation rate but by the nature of chemical kinetics. It is seen that the modifcation of flame structure is mainly due to the preferential diffusion of H2 and thereby the nature of chemical kinetics. It is also found that the behaviors of major species with the three species diffusion models are addressed to the nature of chemical kinetics, and this is evident by examining importantly contributing reaction steps to the production and destruction of those chemical species.

• Asia pacific journal of information systems
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• v.10 no.4
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• pp.1-20
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• 2000

Electronic Data Interchange(EDI) has the potential to improve business operations by expediting the exchange of business documents. It will also provide substantive operational and strategic benefits to the trading firms. However, the successful implementation of EDI systems requires the mutual trust and cooperation between the trading firms. The extent of EDI diffusion and performance depends on inter-organizational, intra-organizational, as well as innovation factors. Researches based on the sociopolitical process framework in the use of IT, organizational theory, resource dependence theory, and innovation diffusion theory have identified 3 inter-organizational variables(transaction climate, dependence, external IS expert support) and 4 intra-organizational variables(strategic IS planning, infrastructure, top management support, education/training,), and 3 innovation variables(compatibility, relative advantage, cost) that affect EDI diffusion. In this study, a multi-dimensional measure on EDI diffusion has been developed to capture the external and internal integration. Then, the influence of these 10 variables on the extent to which the EDI adopting firms pursue diffusion has been examined. Whether more diffusion leads to superior performance has also been studied. International trade managers from 107 firms in the trade industry participated in a field survey. The results based on a structural equation model(SEM), developed using AMOS, provide quite a strong support for the hypothesized relations. Both education/training and IT infrastructure influenced external and internal diffusion of EDI systems. Internal diffusion of EDI enables the adopting firms to improve operational and strategic performance, whereas external diffusion contributes only to operational performance.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.27-37
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• 2008

It is most serious problem which is various occurs from the agricultural concrete structure and off shore concrete structure the problem which it comes to think is deterioration of the concrete which is caused with the corrosion of the reinforcing steel which is caused by with permeation of the water and the sea water. Specially the off shore concrete structure has been deteriorated by the steel reinforcement corrosion. The latex modified concrete(LMC) was adds latex in the plain concrete as the latex has increase the durability of concrete. This study were accomplished to the estimate the diffusion coefficient of LMC, and the time dependent constants of diffusion. The average chloride diffusion coefficient was estimated. Also, the average chloride diffusion coefficient was compared with diffusion coefficient test results of 28 curing days. The test results indicated that the average chloride diffusion coefficient could closely estimate the test results of the diffusion coefficient test results of 28 curing days.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.6
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• pp.725-736
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• 2013

This study segments information users according to depth and variety of use diffusion in order to differentiate between the influence of fashion information spread and diffusions from each segmented group. Data were collected from a fashion community to perform a social network analysis that used UCINET 6.0. Members completed the survey materials and the network materials were utilized in the analysis to test the hypothesis. The segmented groups of information users determined the study results according to use diffusion and the variables that affect them. The variables affecting information diffusion outcomes indicate different significant influence factors on each segmented market. Information variety and complexity represents elevated information reproductions and verbal acceptances from information diffusion outcomes.

• International Journal of Concrete Structures and Materials
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• v.4 no.2
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• pp.109-112
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• 2010

Part I of this study was devoted to the electrical accelerated chloride diffusion in mortars. In this second part, natural chloride diffusion has been investigated for four types of mortars under exposure to a 0.5 mol/L NaCl solution for a period of up to 35 days. Two different types of sand were used for the production of test samples: siliceous sand (used as a reference) and limestone sand (used in this study). The effect of water to cement ratio and exposure time on the diffusion coefficients of mortars was also investigated. In this study, the total and free chloride content and penetration depth of mortar were measured after immersion, and Fick's second law of diffusion was fitted to the experimental data to determine the diffusion coefficient. Their results show that the use of crushed limestone sand in mortar had a positive effect on the chloride resistance. The apparent diffusion coefficient in all specimens was smaller than that in siliceous sand mortar. However, the chloride penetration of these mortars was increased as exposure time progressed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.127-131
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• 2009

The purpose of this study is to provide fundamental data on chloride diffusion from lightweight aggregate concrete by utilizing crushed stone-powder. Accordingly, the study performed experiments using concrete aggregates of Crushed Aggregate (CG), Single-sized Lightweight Aggregate (SLG), Continuous Graded Lightweight Aggregate (CLG), and using water-binder ratio of 0.4, 0.5, 0.6, and using binder of FA and BFS. The chloride diffusion coefficient is calculated after experiment based on NT BUILD 492. Diffusion coefficient of SLG and CLG were little bit higher than CG Concrete, but the difference is meaningless. Also, chloride diffusion coefficient indicates that it is highly affected by water-binder ratio, and it decreases with the decrease in water-binder ratio. The admixture substitution indicates decrease only with water-binder ratio of 0.4 for FA15% case, but admixture substitution indicates decrease with all levels of ratio for FA10 + BFS20% which means more appropriate. According to the analysis result of chloride diffusion from lightweight aggregate concrete, crushed stone-powder utilized lightweight aggregate concrete indicates higher chloride diffusion coefficient than CG concrete, which is not a significant difference, and can improve resistance through water-binder ratio and admixture substitution.

• Magazine of the Korea Concrete Institute
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• v.8 no.5
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• pp.145-154
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• 1996

Polymer-modified mortars have an excellent water proofness and water retentivity. Therefore, the study on the moisture diffusion behavior- is very important. The purpose of' this study is to investigate the effects of relative humidity and moisture content in mortars on the moisture diffusion, and the relationship between the shrinkage and moisture diffusion coefficient of polymer-modified mortars cured at $20{\circ}C$ 50% R.H and 80% R.H. The pore size distribution of the polymer-modified mortars was also measured. From the test results, the relative humidity and moisture content in mortars influenced on the moisture diffusion of polymer-modified mortars. The shrinkage and moisture diffusion coefficient of polymer-modified mortars cured at $20{\circ}C$ 50% R.H. was bigger than that cured at $20{\circ}C$ 80% R.H.. and decreased with increasing polymer-cement ratio regardless of polymer type.

• Journal of Korean Society for Quality Management
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• v.51 no.4
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• pp.691-700
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• 2023

Purpose: This study aims to analyze the diffusion pattern of the Mongolian mobile phone market. In particular, we used a generalized diffusion model to explore the factors affecting market potenial. Methods: We used three diffusion models to estimate the number of mobile subscribers in Mongolia. Based on the Logistic model with the best fitness, we introduced time-varying market potential and explored the influence of various independent variables such as GDP and inflation. Results: Among the basic diffusion models, the Logistic model was the best in terms of estimation performance and statistical significance. The estimation results of the Generalized Logistic model confirm that investment in the telecommunication sector has a significant positive effect on market potential. The estimation of the Generalized Logistic model effectively describes the continuous growth of the Mongolian telecommunications market until recently. Conclusion: We have analyzed the diffusion pattern of the Mongolian telecommunications market and found that the amount of investment in the sector leads to the growth of the market size. This study is original in terms of its subject - Mongolian telecommunications market and methodology - time-varying market potential.