• 제목/요약/키워드: internal diffusion

검색결과 307건 처리시간 0.025초

Moleciular Reorientation in the Presence of the Extended Diffusion of internal Rotation in Liquid Perdeuterotoluene

  • Doo-Soo Chung;Myung-Soo Kim;Jo-Woong Lee;Kook-Joe Shin
    • Bulletin of the Korean Chemical Society
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    • 제4권1호
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    • pp.25-28
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    • 1983
  • The effect of internal rotation of methyl group in liquid perdeuterotoluene on nuclear quadrupole relaxation of methyl deuterons is investigated. A model of a spherical diffusor undergoing rotational diffusion is extended to include the extended diffusion of internal rotation. The overall reorientational correlation time in the presence of internal rotation is explicitly given as an analytical function of the angular momentum correlation time. Also, the degree of inertial effect in the internal rotation is evaluated.

The Combined Effects of Power Imbalance and Mutual Dependence on the Relationship between IOS Diffusion and a Firm's Performance Improvement

  • Gee-Woo Bock;Sang Cheol Park;Won Jun Lee;Cheng Zhang;Kyu Min Hwang
    • Asia pacific journal of information systems
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    • 제29권2호
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    • pp.217-247
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    • 2019
  • This paper draws on the interdependence theory to examine the role of power and mutual dependence on the relationship between internal/external diffusion and performance improvement within a supply chain. The results from a survey of 375 respondents show that two patterns of IOS diffusion - internal diffusion and external diffusion - have different impacts on a firm's performance improvement according to differences in power and mutual dependence between two parties in the supply chain.

Molecular Reorientation of Oblate Symmetric Top Molecules with Internal Extended Rotational Diffusion

  • Shin, Kook-Joe Shin
    • Bulletin of the Korean Chemical Society
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    • 제4권5호
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    • pp.228-230
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    • 1983
  • Molecular reorientation of oblate symmetric top molecules with internal rotation is investigated theoretically and an analytic expression for the overall reorientational correlation time in terms of the internal angular momentum correlation time is derived. This expression is quite different from the expression for prolate symmetric top molecules but reduces to the same expression in the spherical top limit. Fast internal rotation is treated by a modified version of the extended rotational diffusion while the bulky symmetric top mainbody is treated by the rotational diffusion model.

EDI 시스템의 확산과 성과에 관한 실증적 연구 (An Empirical Study on the EDI Diffusion and Performance)

  • 이재원;이영환
    • Asia pacific journal of information systems
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    • 제10권4호
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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.

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Spin-Rotational Relaxation Study of Molecular Reorientation of Oblate Symmetric Top Molecules with Internal Extended Rotational Diffusion

  • Kim, Eun-Mi;Shin, Kook-Joe
    • Bulletin of the Korean Chemical Society
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    • 제10권5호
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    • pp.430-433
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    • 1989
  • Molecular reorientation of oblate symmetric top molecules in the presence of internal rotation is investigated and an analytic expression for the spin-rotational relaxation rate of a nucleus attached to the internal rotor is obtained as a function of the internal angular momentum correlation time. The overall reorientation of the symmetric top is treated by the anisotropic rotational diffusion and the internal rotation is assumed to undergo modified extended rotational diffusion. The result is compared with the previous work for the prolate symmetric top molecule and it is shown that both results reduce to the same expression in the spherical top limit.

Nuclear Magnetic Relaxation of Molecular Reorientation in Liquid

  • Kook Joe Shin
    • Bulletin of the Korean Chemical Society
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    • 제14권1호
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    • pp.110-112
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    • 1993
  • Molecular reorientation of oblate symmetric top molecules in the presence of internal rotation is investigated and an analytic expression for the overall reorientational correlation time is obtained. The overall reorientation of the symmetric top is treated by the anisotropic rotational diffusion and the internal rotation is analyzed by employing a model which describes jumps between several discrete states with different lifetimes. The lifetimes thus obtained can be compared with the internal angular momentum correlation time which appears when the internal rotation is treated by a modified extended rotational diffusion model.

초기재령 콘크리트의 수분확산과 자체건조에 관한 연구 (Moisture Diffusion and Self-desiccation of Concrete at Early Ages)

  • 김진근;이칠성
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
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    • pp.303-308
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    • 1998
  • In the concrete structures exposed to environmental conditions at early ages, water movement occurs by moisture diffusion in the concrete, and self-desiccation of concrete is also occurred. Thus the internal relative humidity is changed from moisture diffusion and self-desiccation. Thus the internal relative humidity at each location in concrete includes the decrease by self-desiccation. Especially, for high-strength concrete the much unit cement content is used, so that the non-uniform relative humidity distribution is affected form self-desiccation at early ages. In this study, the internal relative humidity in concrete was measured at early ages, and the moisture diffusion component and self-desiccation component of total relative humidity were discussed.

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입자의 크기가 PZT 세라믹스의 열화현상에 미치는 영향 (The Effects of Grain Size on the Degradation Phenomena of PZT Ceramics)

  • 정우환;김진호;조상희
    • 한국세라믹학회지
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    • 제29권1호
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    • pp.65-73
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    • 1992
  • The effect of grain size on the time-dependent piezoelectrice degradation of a poled PZT of MPB composition Pb0.988Sr0.012 (Zr0.52Ti0.48)O3 with 2.4 mol% of Nb2O5 was studied, and the degradation mechanism was discussed. Changes in the internal bias field and the internal stress both responsible for the time-dependent degradation of poled PZT were examined by the polarization reveral technique, XRD and Vickers indentation, respectively. The piezoelectric degradation increased with increasing time and grain size, and the internal bias field due to space charge diffusion decreased with increasing grain size of poled PZT. The internal bias field, however, was almost insensitive to the degradation time regardless of the grain size. On the other hand, both the x-ray diffraction peak intensity ratio of (002) to (200) and the fracture behavior including the crack propagation support that the ferroelectric domain rearrangement of larger grain size showed rapid relaxation of the internal stress compared with smaller one, which is thought the origin of the larger piezoelectric degradation in the former. In conclusion, the contribution of space charge diffusion on the piezoelectric degradation of PZT is strongly dependent on both the grain size and the composition. Thus, the relaxation of internal stress due to the ferroelectric domain rearrangement as well as the amount and time-dependence of the internal bias field due to space charge diffusion should be considered simultaneously in the degradation mechanism of PZT.

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Bass 모형을 이용한 인터넷에서의 기술 확산에 대한 실증분석 (An Empirical Study of Technology Diffusion on the Internet using Bass Model)

  • 남호헌;양광민
    • 디지털융복합연구
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    • 제6권2호
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    • pp.55-64
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    • 2008
  • The Internet possesses not only features of mass media but also features of word of mouth communication. Communication channel is considered as one of most important variables in diffusion process. In this paper, we examined functionality of technology diffusion on the Internet through the use of meta tags. We have measured the coefficients of the Bass diffusion model which has been well-established in new product diffusion. This research shows that the Bass model is appropriate for describing technology diffusion on the Internet. The external influence as represented by the coefficient of innovation was found to be much smaller while the internal influence dominates in all meta tag diffusion. In meta tag diffusion, the internal influence as represented by the coefficient of imitation was increased at least twice bigger than that of consumer durables and information technology. Collecting necessary data in social sciences research can be a burden. This research shows that it can be alleviated through the use of software agents over the Internet. The research made use of software agents for collecting longitudinal data from publicly accessible archive such as Archive.org.

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조직적 특성과 혁신유도 특성이 EDI의 확산에 미치는 영향 (A Study on the Relationship between Organizational and Innovational Driven Characteristics and the Diffusion of Electronic Data Interchange)

  • 정윤;노영;강재정
    • Asia pacific journal of information systems
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    • 제7권3호
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    • pp.89-108
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    • 1997
  • This study, drawing upon research in innovation theory and Information systems, investigates the relationship among the organizational and innovation characteristics and the extent of internal and external diffusion of EDI in Korean firms. The data for this study were collected from 131 firms that have implemented EDI. The results of the correlation and the multiple regression analysis show that elapsed time and organizational compatibility are the major predictors of EDI diffusion. Specifically, the extent of communication, elapsed time and organizational compatibility are the major predictors of internal diffusion, while centralization, organizational compatibility and elapsed time are closely related to external diffusion of EDI. The results of this study imply that to facilitate the use of EDI widely within and beyond organizations, EDI system should be compatibile with the organizational tasks, values systems and existing information systems.

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