• 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.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.301-304
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• 2015

With the experiment observation of single particle combustion, this model is built for the numerical analysis of the process. It's about the single coal particle combustion process under different conditions with reasonable assumptions. The model can express the mass, radius, density, temperature changing with different particle sizes, oxygen concentration and gas temperature. It also includes the flame sizes change in different condition and the diffusion of each species. The result shows the characters of the combustion.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.427-442
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• 2011

Calcium is a vital second messenger for signal transduction in neurons. Calcium plays an important role in almost every part of the human body but in neuronal cytosol, it is of utmost importance. In order to understand the calcium signaling mechanism in a better way a finite element model has been developed to study the flow of calcium in two dimensions with time. This model assumes EBA (Excess Buffering Approximation), incorporating all the important parameters like time, association rate, influx, buffer concentration, diffusion constant etc. Finite element method is used to obtain calcium concentration in two dimensions and numerical integration is used to compute effect of time over 2-D Calcium profile. Comparative study of calcium signaling in two dimensions with time is done with other important physiological parameters. A MATLAB program has been developed for the entire problem and simulated on an x64 machine to compute the numerical results.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.3
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• pp.199-212
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• 2023

Diffusion is a powerful tool to understand geological processes recorded in terrestrial rocks as well as extraterrestrial materials. Since the diffusive exchange of elements or isotopes may have occurred differently in the solar nebula (high temperature and rapid cooling) and on the parent bodies (fluid-assisted thermal metamorphism at relatively low temperature), it is particularly important to model elemental or isotopic diffusion profiles within the mineral grains to better understand the evolution of the early solar system. A numerical model with the finite difference method for the fast grain boundary diffusion was established for the exchange of elements or isotopes between constituent minerals in a closed system. The fast grain boundary diffusion numerical model was applied to 1) ²⁶Mg variation in plagioclase of an amoeboid olivine aggregate (AOA) from a CH chondrite and 2) Fe-Mg interdiffusion between chondrules, AOA, and matrix minerals in a CO chondrite. Equilibrium isotopic fractionation and equilibrium partitioning were also included in the numerical model, based on the assumption that equilibrium can be reached at the interfaces of mineral crystals. The numerical model showed that diffusion profiles observed in chondrite samples likely resulted from the diffusive exchange of elements or isotopes between the constituent minerals. This study also showed that the closure temperature is determined not only by the mineral with the slowest diffusivity in the system, but also strongly depends on the constituent mineral abundances.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.3
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• pp.115-124
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• 1997

We measured the variance of eddy diffusion and associated ‘diffusion coefficients’ in coastal regions of Korea by observing the separation distances among multiple drifters deployed simultaneously at the same initial position. The variance of eddy diffusion was found to be proportional to $t^m$, where t is the time and m is a non-integer scaling exponent between 1.5 and 3.5. The observed scaling exponent of eddy diffusion cannot be reproduced by diffusion models employing constant eddy diffusivity. In this study, we applied fractal theory in simulating exponential increase of variance of eddy diffusion. We employed the fGn(fractional Gaussian noise) as a ‘modified’ random walks corresponding to the oceanic eddy diffusion. The variance of eddy diffusion, which corresponds to the fBm(fractional Brown motion) of our diffusion model, is proportional to $t^{2H}$, where H is Hurst scaling exponent. The temporal increase of the variance. with scaling exponent between 1 and 2, was successfully reproduced by our fractal diffusion model. However, our model cannot reproduce scaling exponent greater than 2. The scaling exponents greater than 2 are associated with the velocity shear of the mean flow.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.217-223
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• 1991

A capillary method was used to evaluate the properties of mass transfer process and diffusion coefficients in the gel food. Amaranth dye was selected as a diffusant material to visualize the degree of diffusion procedure easily. After contacting cylinder containing agar gel with amaramth dye solution for some hours, the gel was cut to five segments by 0.5 cm in length. The diffusant concentration from the segments were measured by the spectrophotometer at 523 nm. Prediction models for the diffused quantities in gel food were established by the regression program of SPSS package program. Generally, diffusion coefficient can be calculated by Fick's second law, however, it will be determined by using numerical analysis method more easily. Finally the diffusion coefficients in this research were calculated by arithmetic mean of the measured values. As raising gel agent concentration, the mean diffusion coefficient tended to decrease because the obstruction effect came to become significant.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.5
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• pp.698-707
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• 1998

A simplified model for predicting microsegregation during columnar-dendritic solidification of binary alloys is developed, in which back diffusion, dendrite arm coarsening and dendrite tip undercooling are simultaneously incorporated. The inclusion of tip undercooling is accomplished by modifying the initial conditions of the existing solute diffusion model, in such forms that tip undercooling depresses the beginning of solidification below the liquidus temperature, and that the secondary arm spacing evolves in accordance with the minimum undercooling theory. Sample calculations for the well-known benchmark system show that the present predictions not only consist with the extablished limiting cases, but also agree favorably with the available experimental data within a reasonable tolerance. In particular, a typical decreasing trend in the eutectic fraction at high cooling rates is successfully resolved. Comparison of the individual and combined effects of characteristic parameters in reference with the limiting cases reveals the interactions among parameters. Every parameter plays the role of reducing the eutectic fraction, and the degree of influence depends primarily on the cooling rate. Coarsening enhances the effect of tip undercooling, while suppressing that of back diffusion. A vigorous back diffusion seems to restrain the apperance of the undercooling effect. Overall, each contribution of the three parameters to microsegregation is estimated to be of the same order, which suffices to justify the present study.

• Journal of the Korean Mathematical Society
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• v.43 no.2
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• pp.383-398
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• 2006

We consider a geometric Levy process for an underlying asset. We prove first that the option price is the unique solution of certain integro-differential equation without assuming differentiability and boundedness of derivatives of the payoff function. Second result is to provide convergence rate for option prices when the small jumps are removed from the Levy process.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.2
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• pp.84-90
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• 2014

This paper presents the results of three-dimensional face point cloud smoothing based on a modified anisotropic diffusion method. The focus of this research was to obtain a 3D face point cloud with a smooth texture and number of vertices equal to the number of vertices input during the smoothing process. Different from other methods, such as using a template D face model, modified anisotropic diffusion only uses basic concepts of convolution and filtering which do not require a complex process. In this research, we used 6D point cloud face data where the first 3D point cloud contained data pertaining to noisy x-, y-, and z-coordinate information, and the other 3D point cloud contained data regarding the red, green, and blue pixel layers as an input system. We used vertex selection to modify the original anisotropic diffusion. The results show that our method has improved performance relative to the original anisotropic diffusion method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.16
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• pp.149-158
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• 1987

The Adoption/Diffusion of Innovations(New Product), a topic of study and research that has frown rapidly in the past few decades, deals with how a new product is adopted in a society. It is of high importance to marketing organizations because New Products must be brought out continuously in order to service. The purpose of this paper is to examine the Adoption/Diffusion Models for New product which will help to analyze the Adoption/Diffusion process of Adopters. There are a number of models that, with varying degrees of success, have been used to predict market acceptance of new product. In this paper, following types of new product Adoption/Diffusion Models was suggested. (1) Adoption Models : The Alternative Models of Adoption. The Rogers Model of the Innovation Decision Process. (2) Diffusion Models : First Purchase Models(Basic Models, Extension of the Basic Models), Repeat Purchase Models