• 제목/요약/키워드: Diffusion theory

검색결과 481건 처리시간 0.026초

확산형 흡수식 냉동기용 기포펌프의 운전특성에 관한 연구 (Operating Characteristics of a Bubble Pump for Diffusion-Absorption Refrigerator)

  • 이현경;김선창;이재헌
    • 설비공학논문집
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    • 제13권9호
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    • pp.878-887
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    • 2001
  • Experimental investigation has been carried out to examine the operating characteristics of a bubble pump for diffusion absorption refrigerator. The effects of heat input and delivery height on generation rate of refrigerant vapor and circulation rate of solution have been investigated. as a result heat input and delivery height increase, circulation rate of solution increases. And the smaller the tube diameter, the larger the circulation rate of solution. Pumping ratio increases to a critical point and then decrease with the increase of heat input, and it increases with the increase in delivery height. In this paper, Marcus's analytical theory was also examined. It was found that the Marcus\`s analytical theory of a bubble pump was not appropriate for a bubble pump using ammonia aqueous solution as a working fluid.

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Development of the Discrete-Ordinates, Nodal Transport Methods Using the Simplified Even-Parity Neutron Transport Equation

  • Noh, Taewan
    • Nuclear Engineering and Technology
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    • 제32권6호
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    • pp.605-617
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    • 2000
  • Nodal transport methods are studied for the solution of two dimensional discrete-ordinates, simplified even-parity transport equation(SEP) which is known to be an approximation to the true transport equation. The polynomial expansion nodal method(PEN) and the analytic function expansion nodal method(AFEN)which have been developed for the diffusion theory are used for the solution of the discrete-ordinates form of SEP equation. Our study shows that while the PEN method in diffusion theory can directly be converted without complication, the AFEN method requires a theoretical modification due to the nonhomogeneous property of the transport equation. The numerical results show that the proposed two methods work well with the SEP transport equation with higher accuracies compared with the conventional finite difference method.

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Continuance Intention Toward Second-generation Mobile Instant Messaging App of LINE in Taiwan

  • Bao Q. Duong;Charlie Chen;Craig Van Slyke
    • Asia pacific journal of information systems
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    • 제33권4호
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    • pp.899-933
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    • 2023
  • The second-generation mobile instant messaging (SMIM) proliferates with various relationship management functions: group chats, audio/video chats, file sharing, real-time location sharing, and nonverbal graphics, such as emojis and stickers. This study integrates the important but often overlooked affordances theory into innovation diffusion and proposes an SMIM continuance intention model. SMIM is a social affordance platform for users to develop new friendships and maintain their relationships. Integrated diffusion of innovation and affordance theoretical frameworks, this study investigates the influence of four factors on the success of using SMIM apps to improve friendship development and relationship management. Data were collected from 231 participants using a survey questionnaire in a public university in Taiwan. The findings confirm the effects of friendship development and relationship maintenance on the intention of users to continue using SMIM apps. Implications for research and practice are discussed.

핀테크 지급결제 서비스 수용 저항요인 연구 : 혁신저항이론과 현상유지편향이론을 중심으로 (The Study of User Resistance to Fintech Payment Service: In the Perspective of Innovation Diffusion And Status Quo Bias Theory)

  • 황신해;김정군
    • 한국정보시스템학회지:정보시스템연구
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    • 제27권1호
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    • pp.133-151
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    • 2018
  • Purpose Global fintech industry is proliferating. Although domestic investment in fintech service is also increasing fast, user acceptance of fintech payment service seems slower than expected. Previous fintech literature mainly focuses on overall characteristics and technical aspects of fintech including security issues and explores factors affecting the service adoption. This study aims to examine crucial factors affecting user's resistance intention to fintech payment service adoption. The research model was formulated based on innovation diffusion theory and status quo bias theory and validated empirically. Design/methodology/approach The proposed research model was empirically validated with 149 responses from college students who have used fintech payment service. The component-based SEM was employed for data analysis. Findings The significant findings are as follow. First, compatibility has significant negative effect and complexity, and perceived risk has a positive effect on user resistance. Second, institutional trust does not show a significant effect on user resistance but has an indirect effect through the mediation of trust in service provider. Finally, trust in service provider shows the significant negative effect on user resistance.

혁신확산이론에 따른 스마트폰 수용의도에 관한 연구: 스마트폰 미사용자를 중심으로 (A Study on the Acceptance Intention for Smart Phone by the Innovation Diffusion Theory: Focused on Smart Phone Non-Users)

  • 김정욱;김성일
    • 한국IT서비스학회지
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    • 제11권1호
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    • pp.15-37
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    • 2012
  • This study is progressed for understanding of the acceptance intention differentiated through the view of smart phone non-user's adopting plan. And the research model is proposed in the view of new technology adopting, Innovation Diffusion Theory, Rogers 1995, and Technology Acceptance Model, Davis 1989. In the survey, SPSS 18.0 and AMOS 18.0 are used to analyze the 685 smart phone non-users data. The results of the feasibility analysis and the factor analysis show the measured variables determined in the statistical significant range. Also, 11 hypotheses, among the 16 hypotheses, are adopted by the hypothesis tests through the path analysis, one-way-ANOVA and hierarchial regression analysis. The results indicate variables affect on the non-smart phone user's adopting intention. The primary factor is the perceived usefulness, secondary factor is the social property, and the rest is the playfulness. And, the primary adoption factor is affected to early majority and late majority among each innovation adopters.

XBRL Adoption Process in Malaysia Using Diffusion of Innovation Theory

  • ILIAS, Azleen;GHANI, Erlane K.;AZHAR, Zubir
    • The Journal of Asian Finance, Economics and Business
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    • 제8권2호
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    • pp.263-271
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    • 2021
  • The study examined the XBRL adoption process of Malaysian Business Reporting System (MBRS) by utilizing Everett Rogers' Diffusion of Innovation (DOI) theory. The study focused on the three phases, namely, knowledge gathering and persuasion phase, decision-making phase, and implementation phase of XBRL adoption process gathered from a government agency in Malaysia. This study employs a qualitative case study that incorporates semi-structured interviews with four members of the regulator. The results reveal that the regulator has realized the advantages, management support, and need to skills development in phase one. On the other hand, in phase two, it finds the way the regulator makes decision related to XBRL taxonomy and submission template, platform, tools and software. Through phase three, the regulator is concerned with the complexity of XBRL taxonomy, resources, external support, promotion, stakeholder involvement, limited trading pressure, critical mass, and professional bodies. The factors from each phase suggest an in-depth understanding on the experience of XBRL through the development of MBRS that provides a success story to the other government agencies and regulators in Malaysia. This study provides several insights on the factors that could contribute to the adoption of XBRL and the Diffusion of Innovation theory adoption process.

촉매담체내에서 방향족 화합물의 역확산 (Counter-diffusion of Aromatic Compounds in Catalyst Supports)

  • 정경환;서곤
    • 공업화학
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    • 제10권4호
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    • pp.608-614
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    • 1999
  • 촉매 담체로 사용되는 알루미나와 실리카-알루미나에 흡착된 tetra-phenylprophine과 coronene이 아세톤의 주입에 의해 탈착되는 역확산 과정과, coronene이 tetra-phenylporphine 용액에 의한 역확산 과정을 조사하였다. 이상흡착용액 이론을 적용한 역확산 모델을 이용하여 역확산 과정을 해석하고 모사한 결과로부터 역확산 계수를 결정하였다. 과량의 아세톤 주입에 의한 탈착에서 tetra-phenylporphine과 coronene의 역확산 계수는 ${\sim}10^{-15}m^2/sec$ 범위로 얻어졌다. 흡착용액과 비슷한 농도를 갖는 tetra-phenylprophine 용액에 의한 역확산의 경우 탈착되는 coronene의 역확산 계수의 값도 ${\sim}10^{-15}m^2/sec$ 범위에 있으며, 세공내로 들어가는 tetra-phenylporphine의 확산 계수는 ${\sim}10^{-11}m^2/sec$ 이었다. 흡착제 밖으로 탈착되어 나오는 coronene의 역확산 계수는 아세톤이나 tetra-phenylporphine 용액의 주입에 의한 흡착-탈착의 경우 탈착제는 종류와 양에 관계없이 모두 비슷한 범위의 값을 보여 주었다. 역확산계수는 비어 있는 세공내로의 확산에 대한 유효확산계수에 비해 현저히 감소하였다. 이러한 현상은 역확산 과정에 나타나는 확산 흐름의 교차에 기인하는 것으로 설명되었다.

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Facilitated Protein-DNA Binding: Theory and Monte Carlo Simulation

  • Park, Ki-Hyun;Kim, Tae-Jun;Kim, Hyo-Joon
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.971-974
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    • 2012
  • The facilitated diffusion effect on protein-DNA binding is studied. A rigorous theoretical approach is presented to deal with the coupling between one-dimensional and three-dimensional diffusive motions. For a simplified model, the present approach can provide numerically exact results, which are confirmed by the lattice-based Monte Carlo simulations.

Drift Diffusion of Radiation-produced Point Defects to Edge Dislocation

  • Park, S.S.;Chang, K.O.;Choi, S.P.;Kim, C.O.
    • Nuclear Engineering and Technology
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    • 제31권2호
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    • pp.151-156
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    • 1999
  • Under the heavy irradiation of crystalline materials 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 appropriate transformation of these nonlinear differential equations to more solvable Poisson's equations, finally 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.

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