• Journal of Information Technology Services
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• v.8 no.1
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• pp.11-27
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• 2009

Recently, IPTV attracts great attention along with the digital convergence of communication and media technologies. This study examined critical factors on the consumer's continued use of the IPTV service. Based on the expectation-confirmation theory and the innovation diffusion theory, we derived nine key factors in the research model-relative advantage, compatibility, ease of use, image, diversity of contents, interactivity, monetary value, social influence, and user satisfaction. Using the partial least square method, we found that content diversity and compatibility have a significant indirect effect on the continued use of the IPTV service via user satisfaction, and user satisfaction and social influence also have a significant direct impact on the IPTV use. These findings not only provide practical insights on the consumer acceptance of new technology-converging services, but also help managers to plan their marketing strategies better.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.8
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• pp.366-374
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• 2014

Experimental mass transfer data, which were obtained for the $CO_2$-water slug flows in vertical tubes with 2, 5, and 8mm diameters, were analyzed in comparison with the penetration theory. It was found that a penetration model with molecular diffusion coefficient cannot predict the experimental data accurately. An effective diffusion coefficient, which considers enhancement effect of interfacial waves, was suggested to improve prediction. Another empirical factor was also suggested to consider the effect of non-uniform interface velocity. A modified penetration model was found to be capable of predicting the experimental data reasonably well.

• Journal of the Korean Mathematical Society
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• v.38 no.2
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• pp.385-408
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• 2001

This is an introduction to a stochastic version of E. Cartan′s symplectic mechanics. A class of time-symmetric("Bernstein") diffusion processes is used to deform stochastically the exterior derivative of the Poincare-Cartan one-form on the extended phase space. The resulting symplectic tow-form is shown to contain the (a.e.) dynamical laws of the diffusions. This can be regarded as a geometrization of Feynman′s path integral approach to quantum theory; when Planck′s constant reduce to zero, we recover Cartan′s mechanics. The underlying strategy is the one of "Euclidean Quantum Mechanics".

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.169-172
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• 1995

Establishment of a diagnosing technology for the deterioration of reinforced concrete structures due to salt contamination is urgent, but few analytical methods based on measured data obtained from concrete structures have been presented so far. Chloride penetration into concrete from sea water is generally understood and analysed as diffusion of chloride ion. This paper presents a new method of predicting chloride penetration into concrete based on diffusion theory. Also, it determines the duralility of Marine structure in service with the prediction of remaiing lifetime by the carvonation test.

• Laser Solutions
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• v.4 no.3
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• pp.40-44
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• 2001

Microbump formation during CO$_2$ laser texturing of glass substrates is examined in this paper. Experimental results show that different bump shapes (dome-shaped, with a central dimple, and with a peripheral rim) are generated depending on the laser fluence. A theoretical model for the process is suggested based on thermoelastic behavior but limited only to the dome-shaped bump. The dimensions (maximum height and base area) of the bump shows a logarithmic dependence on laser fluence as expected from the theory. Numerical computation reveals that the effect of thermal diffusion is not negligible for relatively long laser pulses.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.160-165
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• 1998

Under the heavy irradiation, when the production and the recombination of interstitials and vacancies are included, the diffusion equations become nonlinear. An effort has been made to arrange an appropriated transformation of these nonlinear differential equations to soluble Poisson's equations, so that analytical solutions for simultaneously calculating the concentrations of interstitials and vacancies in the angular dependent Cottrell's potential of the edge dislocation have been derived from the well-known Green's theorem and perturbation theory.

• Bulletin of the Korean Chemical Society
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• v.15 no.4
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• pp.311-320
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• 1994

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.543-553
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• 1998

본 연구는 1960년부터 1975년까지 미국여성복식에 나타났던 인도디자인(Indian design)의 내용을 여러 사회계층으로 나누어 세부적으로 검토, 분석해 보고자 하였다. 지금까지 하위문화 선도이론(subcultural leadership theory)외 하나의 예로서, 미국복식에 나타났던 인도디자인이 반문화적 현상(counterculral phenomenon)으로 청년복식에서 제일 먼저 채택되었으며 점차 사회전반의 복식에, 더 나아가 상류계층복식 (high fashion)으로 확산되었다는 이론을 사회과학 분야에서 주로 사용되어왔던 수량적 연구방법인 내용분석법(content analysis)을 이용하여 실증적으로 분석하였다. 분석된 자료는 총 1043개, 22가지의 종류(subcategory)의 인도 디자인으로. 이러한 결과로 인도의 영향을 받은 디자인이 미국사회 전체의 여성복식에 폭 넓게 나타났으며, 그 절정 시기가 1967년에서 1971년 사이로 이시대의 사회문화의 특징이 복식의 형태에 잘 반영되고 있음이 밝혀졌다. 더불어, 각 인도디자인은 최초 출현시기, 절정시기, 지속기간, 디자인의 기원(origin)의 면에서 복잡하고 다양한 양상을 보이므로, 이 시대에 보여진 인도디자인을 채택하는 복식현상은 각 디자인 별로 (case-by-case), 여러 단기간으로 나누어서, 복합적인 패션전파이론(fashion diffusion theory)을 적용하여 설명하는 것이 바람직하다고 보았다.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.278-285
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• 2005

In the present work, a reaction of sulfur removal and simulation of desulfurization based on the grain model and two-phase theory were studied using natural manganese ore (NMO) as a sorbent in a continuous fluidized bed reactor. The effect of desulfurization was investigated through the grain model considered the change of pore structure as a function of desulfurization time, particle size of NMO, and diffusion velocity of $SO_2$ in the pores. Among these parameters, the diffusion of $SO_2$ in the pores of NMO was the most important factor. Moreover, the reaction of sulfur removal and desulfurization in a continuous fluidized bed reactor using NMO as a sorbent could be well predict through the grain model and two-phase theory, respectively.

• The Journal of Information Systems
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• v.21 no.1
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• pp.173-203
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• 2012

In this paper, we arrange the concept of 'Green' in SCM after literature study of Green SCM and investigate causal relationships between influencing factors, practice level and environmental performance focused on Korean firms empirically and conduct path analysis for hypothesis test using partial least squares regression with bootstrap. Firstly, we divide influencing factors of Green SCM into environmental and organizational factors through the previous studies of innovation diffusion theory and environmental management theory, and then we selected 'uncertainty', 'competitiveness' as the environmental factors and 'top management support', 'perceived benefit', 'training' as the organizational factors. Secondly, we classify practice level of Green SCM into 'internal environmental management', 'green purchasing', 'eco-design'. Finally, we selected 'financial performance', 'environmental performance' as the organizational performance. We conducted a survey on the middle manager of manufacturing companies implementing SCM and an empirical analysis. The results of analysis show that there exist causal relationships between influencing factors, practice level, and environmental performance of Green SCM. We expect that the result of this study will suggest useful information to managers who are responsible for SCM to design and execute Green SCM in strategic perspectives.