• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.154-161
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• 2010

The aim of this study was to investigate antibacterial activities of essential oil from C. morifolium against four Grampositive bacteria and six Gram-negative bacteria. The antibacterial activity of the oils was determined by agar-well diffusion assay, minimum inhibitory concentration(MIC), and minimum bactericidal concentration(MBC). Essential oil of C. morifolium had a large inhibition zones especially against Salmonella enterica(21 mm) and Bacillus cereus(19 mm). Essential oil of C. morifolium generally showed higher antibacterial activity against Gram-positive bacteria than Gram-negative bacteria. MIC of essential oil from C. morifolium was 5 ${\mu}g/m{\ell}$ against ten food-borne pathogens. MBC values were determined to be from 5 to 20 ${\mu}g/m{\ell}$ against eight bacteria except Salmonella choleraesuis and Listeria monocytogenes. Therefore, the essential oil of C. morifolium and its components have a potent antibacterial activity against food-borne pathogens, and is expected to be used as a novel food preservative.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.133-146
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• 2013

While the use of internet is routine nowadays, users receive and share information through a variety of media. Through the use of internet, information delivery media is diversifying from traditional media of one-way communication, such as newspaper, TV, and radio, into media of two-way communication. In contrast of traditional media, blogs enable individuals to directly upload and share news, which can be considered to have a differential speed of information diffusion than news media that convey information unilaterally. Therefore this Study focused on the difference between online news and social media blogs. Moreover, there are variations in the speed of information diffusion because that information closely related to one person boosts communications between individuals. We believe that users' standard of evaluation would change based on the types of information. As well, the speed of information diffusion would change based on the level of proximity. Therefore, the purpose of this study is to examine the differences in information diffusion based on the types of media. And then information is segmentalized and an examination is done to see how information diffusion differentiates based on the types of information. This study used the Bass diffusion model, which has been frequently used because this model has higher explanatory power than other models by explaining diffusion of market through innovation effect and imitation effect. Also this model has been applied a lot in other information diffusion related studies. The Bass diffusion model includes an innovation effect and an imitation effect. Innovation effect measures the early-stage impact, while the imitation effect measures the impact of word of mouth at the later stage. According to Mahajan et al. (2000), Innovation effect is emphasized by usefulness and ease-of-use, as well Imitation effect is emphasized by subjective norm and word-of-mouth. Also, according to Lee et al. (2011), Innovation effect is emphasized by mass communication. According to Moore and Benbasat (1996), Innovation effect is emphasized by relative advantage. Because Imitation effect is adopted by within-group influences and Innovation effects is adopted by product's or service's innovation. Therefore, ours study compared online news and social media blogs to examine the differences between media. We also choose different types of information including entertainment related information "Psy Gentelman", Current affair news "Earthquake in Sichuan, China", and product related information "Galaxy S4" in order to examine the variations on information diffusion. We considered that users' information proximity alters based on the types of information. Hence, we chose the three types of information mentioned above, which have different level of proximity from users' standpoint, in order to examine the flow of information diffusion. The first conclusion of this study is that different media has similar effect on information diffusion, even the types of media of information provider are different. Information diffusion has only been distinguished by a disparity between proximity of information. Second, information diffusions differ based on types of information. From the standpoint of users, product and entertainment related information has high imitation effect because of word of mouth. On the other hand, imitation effect dominates innovation effect on Current affair news. From the results of this study, the flow changes of information diffusion is examined and be applied to practical use. This study has some limitations, and those limitations would be able to provide opportunities and suggestions for future research. Presenting the difference of Information diffusion according to media and proximity has difficulties for generalization of theory due to small sample size. Therefore, if further studies adopt to a request for an increase of sample size and media diversity, difference of the information diffusion according to media type and information proximity could be understood more detailed.

• KIEAE Journal
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• v.17 no.3
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• pp.119-124
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• 2017

Purpose: Groundwater heat pump (GWHP) system has high coefficient of performance than conventional air-source heat pump system and closed-loop type geothermal system. However, there is problem in long-term operation that groundwater raise at the diffusion well and reduced at the supply well. Therefore, it is necessary to accurately predict the groundwater flow, groundwater movement and control the groundwater level in the wells. In this research, in consideration of hydrogeological characteristic, groundwater level and groundwater movement were conducted analysis in order to develop the optimal design method of the two-well system using the pairing pipe. Method: For the optimum design of the two-well system, this research focused on the design method of the pairing pipe in the simulation model. Especially, in order to control the groundwater level in wells, pairing pipe between the supply well and diffusion well was developed and the groundwater level during the system operation was analyzed by the numerical simulation. Result: As the result of simulation, the groundwater level increased to -2.65m even in the condition of low hydraulic conductivity and high pumping flow rate. Consequently, it was found that the developed system can be operated stably.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.1
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• pp.33-40
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• 2011

In the compacted bentonite containing $Ag_2O$, the transport of iodide ion was investigated by Through-diffusion method. It is confirmed that Iodide ion is transported by diffusion process in the compacted bentonite containing $Ag_2O$ as well as in the compacted bentonite without $Ag_2O$. However, the lag-time of iodide ion in the compacted bentonite containing $Ag_2O$ is larger than that in the compacted bentonite without $Ag_2O$. The increase of the lag-time was observed in pure iodide ion solution and also in 0.1M NaCl-iodide ion solution. The apparent diffusion coefficient of iodide ion in the compacted bentonite containing $Ag_2O$ has lower value than that in the compacted bentonite without $Ag_2O$. The effect of $Ag_2O$ on the effective diffusion coefficient was not clearly investigated in the compacted bentonite containing $Ag_2O$ while the values of effective diffusion coefficient of iodide ion in the compacted bentonite without $Ag_2O$ obtained in this study were similar to those in the compacted bentonite reported in the literature.

• Journal of Distribution Science
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• v.14 no.5
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• pp.71-80
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• 2016

Purpose - In case of automobile parts, there has been a lot of progress in the study on supplier development plans and SCM in industrial progress study as well as on the relationship between ERP and SCM. But supplier development program providers have researched on SCM performance in accordance with the interests of the supplier development program most, thus, buyers were knowledgeable about the earlier program performance. Therefore, the purpose of this study is to prove correlation factor, supplier factor, purchaser factor affecting SCM performance and ERP activating diffusion through the process of supplier development. Supplier development maturity formation model is considered important variables as mediators related to the procedure. Finally, the performance formation model of the supplier development maturity through supplier development factor would be presented as the outcome of this study. Research design, data, and methodology - Data gathering was as follows: questionnaires were delivered to 87 companies that have business connection with H Company. The empirical research to test our hypothesis was grounded on statistical analysis (adapting SPSS 19.0 & AMOS 19.0). The hypothesis is that the supplier development factor variables consist of correlation factor, supplier factor, purchaser factor, and have non-negative effects on the next variables: mediators such as supplier development maturity; and the supplier development maturity variables have a positive effect on the next variables: ERP activating diffusion, ERP activating diffusion has a non-negative effect on supply chain performance. We experimented the hypothesized model using path analysis with latent variables. Results - First, it was known that cooperation

, reliability

, comprehension on the purpose of SDP

, adaptation of change

, knowledge transfer program

, have significant positive effects on supplier development maturity. Second, supplier development maturity has positive effects significantly on ERP activating diffusion

. Finally, the causal relationships from ERP activating diffusion to SCM performance were significantly accepted. Its significance, as through the hypotheses, presented a structural model for the elaboration, suppliers develop maturity, and ultimately SCM performance that affect ERP leveraging spread beyond the concept of maturity of information system. Therefore, it was a mainstay of research on the existing ERP has they believed. Conclusion - First, with the fast changes in business circumstances, company should get the right information to implement SCM appropriately. For successful SCM, firms should understand the supplier development maturity formation and ERP activating diffusion. Second, supplier development factor has significant effects on supplier development maturity. Third, mediator such as supplier development maturity significantly affects ERP activating diffusion. Finally, ERP activating diffusion has significant impacts on SCM performance. This study makes a meaningful contribution to further appreciation on how supplier development maturity formation affects SCM performance. This study shows implications. First, there would not have been dealt with introducing the concept of supplier development maturity. Second, through empirical analysis and provider factors, the providers will develop the maturity that affect interactive factors between purchaser and supplier.

• Computers and Concrete
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• v.8 no.2
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• pp.125-142
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• 2011

In the present paper, a numerical simulation method based on mesoscopic composite structure of concrete, the truss network model, is developed to evaluate the diffusivity of concrete in order to account for the microstructure of concrete, the binding effect of chloride ions and the chloride concentration dependence. In the model, concrete is described as a three-phase composite, consisting of mortar, coarse aggregates and the interfacial transition zones (ITZs) between them. The advantage of the current model is that it can easily represent the movement of mass (e.g. water or chloride ions) through ITZs or the potential cracks within concrete. An analytical method to estimate the chloride diffusivity of mortar and ITZ, which are both treated as homogenious materials in the model, is introduced in terms of water-to-cement ratio (w/c) and sand volume fraction. Using the newly developed approaches, the effect of cracking of concrete on chloride diffusion is reflected by means of the similar process as that in the test. The results of calculation give close match with experimental observations. Furthermore, with consideration of the binding capacity of chloride ions to cement paste and the concentration dependence for diffusivity, the one-dimensional nonlinear diffusion equation is established, as well as its finite difference form in terms of the truss network model. A series of numerical analysises performed on the model find that the chloride diffusion is substantially influenced by the binding capacity and concentration dependence, which is same as that revealed in some experimental investigations. This indicates the necessity to take into account the binding capacity and chloride concentration dependence in the durability analysis and service life prediction of concrete structures.

• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1554-1560
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• 2008

The probe diffusion and friction constants of methyl yellow (MY) in liquid n-alkanes of increasing chain length were calculated by equilibrium molecular dynamics (MD) simulations at temperatures of 318, 418, 518 and 618 K. Lennard-Jones particles with masses of 225 and 114 g/mol are modeled for MY. We observed that the diffusion constant of the probe molecule follows a power law dependence on the molecular weight of nalkanes, DMY${\sim}M^{-\gamma}$ well. As the molecular weight of n-alkanes increases, the exponent $\gamma$ shows sharp transitions near n-dotriacontane ($C_{32}$) for the large probe molecule (MY2) at low temperatures of 318 and 418 K. For the small probe molecule (MY1) $D_{MY1}$ in $C_{12}$ to C80 at all the temperatures are always larger than Dself of n-alkanes and longer chain n-alkanes offer a reduced friction relative to the shorter chain n-alkanes, but this reduction in the microscopic friction for MY1 is not large enough to cause a transition in the power law exponent in the log-log plot of DMY1 vs M of n-alkane. For the large probe molecule (MY2) at high temperatures, the situation is very similar to that for MY1. At low temperatures and at low molecular weights of n-alkanes, $D_{MY2}$ are smaller than $D_{self}$ of n-alkanes due to the relatively large molecular size of MY2, and MY2 experiences the full shear viscosity of the medium. As the molecular weight of n-alkane increases, $D_{self}$ of n-alkanes decreases much faster than $D_{MY2}$ and at the higher molecular weights of n-alkane, MY2 diffuses faster than the solvent fluctuations. Therefore there is a large reduction of friction in longer chains compared to the shorter chains, which enhances the diffusion of MY2. The calculated friction constants of MY1 and MY2 in liquid n-alkanes supported these observations. We deem that this is the origin of the so-called“solventoligomer”transition.

• Journal of Internet Computing and Services
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• v.11 no.5
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• pp.37-58
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• 2010

This study analyzes appropriate government policy frameworks for promoting IPTV industry by studying the way of adoption and diffusion of IPTV services. Until recently, most researches on government policies for technology adoption have focused on the personal context. This research adopts two theories, i.e., innovation characteristics theory for personal context and implementation process theory for organizational context. It also hypothesizes that the innovation characteristics more influence on the behavioral intention for usage new media in the level of personal innovativeness is high. Moreover, in the level of expectancy for diffusion policy is high, the implementation of IPTV services more influences on the behavioral intention. The results by statistical analysis, it is found that the higher the level of personal innovativeness is, and the higher the level of expectancy for diffusion policy is, the more behavioral intention will be influenced by the characteristics of innovation and implementation of IPTV service. Thus it is important for government agencies to find the way to facilitate personal innovativeness as well as expectancy for diffusion policy.

• Journal of the Korea Institute of Building Construction
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• v.11 no.4
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• pp.371-378
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• 2011

Concrete is affected by various deterioration factors, such as $CO_2$ and chloride ions from the sea, which cause carbonation and salt attack on concrete. These deterioration phenomena cause steel corrosion in RC structures. Although a great deal of research has been carried out in this area thus far, it is difficult to know the point at which corrosion will occur to a reinforced bar. As the diffusion of deterioration factors depends on the water content in concrete, it is imperative to assess the condition of absorbed water content. A mass measuring method was applied to calculate the absorbed water diffusion coefficient, as well as non-linear finite element method(FEM) analysis. As a result, it was found that W/C and unit water content in concrete mixture affect the diffusion coefficient decision.

• Journal of the Economic Geographical Society of Korea
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• v.1 no.1
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• pp.137-149
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• 1998

It is likely that the spatial structure of the intraurban accessibility as well as the accessibility value of each of the nodes in the subway network is affected by the addition of new linkages. The changes in the accessibility at individual nodes also affect the accessibility in the surrounding areas at some distances away from the nodes. Graph-theoretic algorithms have been developed as a proper measurement scheme for the nodal accessibility in tracked transport networks such as subway networks. However, the graph-theoretic measurements have limitations to estimate the spatial diffusion effect on the surrounding areas. This study proposes a new model for the spatial diffusion effect estimation of nodal accessibility increment in the subway network toward the surrounding areas. Since the distance decay trend of subway station use reflect the spatial diffusion effect of the accessibility of subway station toward the surrounding area. The model is deduced from the subway station use density function which is formulated by the questionnaire survey data.