• Title/Summary/Keyword: Self diffusion

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Characterization of coupling optical modulator to the applied frequency (인가주파수에 따른 결합형 광변조기 특성변화)

  • 강기성
    • Electrical & Electronic Materials
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    • v.9 no.6
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    • pp.584-592
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    • 1996
  • Coupling optical modulator which on the $LiTaO_3$ substrate is fabricated by using proton exchange method and self-aligned method. Proton exchange of proton diffusion method was applied to pattern a waveguide on $LiTaO_3$ substrate. The annealing at >$400^{\circ}C$ was carded out to control waveguide width and depth. The depths of the two annealed optical waveguides, which were measured by using .alpha.-step, were 1.435 K.angs. and 1.380 K.angs. Using .alpha.-step facility, we examined that the width of waveguides is increased from 5.mu.m to 6.45 .mu.m and 6.3.mu.m due to the annealing effects. The process of proton exchange was done at 150.deg. C for 120 min, >$200^{\circ}C$ for 60 min and annealing process was done at >$400^{\circ}C$ for 90 min, >$400^{\circ}C$ for 60 min. The high speed coupling optical modulator has very good figures of merits; the measured high frequency power were achieved.

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Modeling the Knowledge Processing System through the Lens of Complexity Theory : Social Energies, Leadership, and the LIFE Model

  • Faucher, Jean-Baptiste P.L.;Everett, Andre M.;Lawson, Rob
    • Journal of Information Technology Applications and Management
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    • v.17 no.3
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    • pp.191-211
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    • 2010
  • Existing models of knowledge processing do not feature a systemic meaning of knowledge management and ignore the role of leadership and social energy in the knowledge processing system (KPS). This conceptual paper introduces the Leadership Invigorating Flows of Energies, (LIFE) Model as an attempt to remedy that situation and provide a more useful description of the KPS. The LIFE Model highlights the role of emergent leadership and flows of social energies as forces encouraging knowledge creation and dynamic diffusion within an organization through the Knowledge Processing Cycle in eight activities interacting with its social knowledge base in a self-organizing system.

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STOCHASTIC SCALING EFFECT AND STATISTICS OF COSMOLOGICAL DENSITY FLUCTUATIONS

  • Yi, In-Su;Vsihniac, Ethan T.
    • Publications of The Korean Astronomical Society
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    • v.7 no.1
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    • pp.51-61
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    • 1992
  • The nonlinear stochastic behavior of chaotic inflation is characterized by the 'scaling' effect. Using a simple criterion for the appearance of scaling behavior in the ${\lambda}{\phi}^4$ inflation model, we show explicitly that in this limit the onset of the scaling regime does not require any special initial conditions and that it is independent of the self-coupling constant ${\lambda}$. Non-Gaussian statistics in adiabatic fluctuations are important only for super-horizon scales and the scaling regime does not lead to any significant statistical properties on currently observable scales. However, the scaling effect gives some cosmological consequences very different from what we expect in the naive diffusion approximation for quantum fluctuations. The classical (deterministic) treatment of the inflation field (essentially a quantum mechanical object.) becomes valid towards the end of inflation.

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$\mu$CP Process Technology for Nanopattern Implementation (나노패턴 구현을 위한 $\mu$CP 공정기술)

  • 조정대;신영재;김광영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.624-627
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    • 2003
  • Microcontact printing (uCP) of alkanethiols on gold was the first representative of soft-lithography processes. This is an attempt to enhance the accuracy of classical to a precision comparable with optical lithography, creating a low-cost, large-area, and high-resolution patterning process. Microcontact printing relies on replication of a pattered PDMS stamp from a master to form an elastic stamp that can be inked with a SAM solution(monolayer -forming ink) using either immersion inking or contact inking. The inked PDMS stamp is then used to print a pattern that selectively protects the gold substrate during the subsequent etch.

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Problems in Localization of Extension Educators in Korea (농촌지도직 공무원 지방직 전환의 문제)

  • Kim, Sung-Soo
    • Journal of Agricultural Extension & Community Development
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    • v.7 no.1
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    • pp.247-254
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    • 2000
  • Since 1997, Korean government changed the status of extension educators from central government staff to county/city government staff for the sake of democratization and localization, regardless of opposition of academic society of extension professionals. Localization of extension educators followed by government restructuring in Korea, resulted various problems, such as 1) Decreased morale and number of extension educators, thus weakening the extension educational function, 2) Weakened linkages between national and local extension offices, 3) Less opportunity for in-service edition of extension educators, 4) Weakened linkages between agricultural research and extension, etc. During the last 30 years, extension services have helped Korean farmers in achieving self sufficiency of rice and year around supply of green vegetables by diffusion of vinyl house technology. Various problems after three years of localization of extension educators were discussed between announcer of radio KBS and a professor of extension in an interview format, and it was concluded that national efforts should be needed to restore morale of extension educators to continually achieve the national goals of food production, balanced national development and preservation of environment, at the same time to meet increasing needs of farmers.

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A Study of Threshold stress during High Temperature Creep of $\textrm{BN}_f$/Al-5, wt% Mg Metal Matrix Composite (BN 입자 강화 Al-5wt% Mg 기지 복합재료의 고온 크립 변형에서의 임계응력 해석)

  • Song, M.H.;Kwon, H.;Kim, Y.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2000.04a
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    • pp.187-191
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    • 2000
  • High temperature creep behaviour of Al-5 wt% Mg alloy reinforced with 7.5% BN flakes was studied. The composite specimens showed two main creep characteristics : (1) the value of the apparent stress exponent of the composite was high and varied with applied stress (2) the apparent activation energy for creep was much larger than that for self-diffusion in aluminum The true stress exponent of the composite was set equal to 5. Temperature dependence of the threshold stress of the composite was very strong. Which could not be rationalized by allowing for the temperature dependence of the elastic modulus change. AIN particles which were incorporated into the Al matrix during fabrication of the composite by the PRIMEXTM method were found to be effective barriers to dislocation motion and to give rise the threshold stress during creep of the composite

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A Study on the Capital Area's Urban Type Analysis and Real Estate Characteristics

  • Jeong, Moonoh;Lee, Sangyoub
    • Journal of Construction Engineering and Project Management
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    • v.2 no.4
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    • pp.32-41
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    • 2012
  • In recent times, multi-centralization and decentralization as well as large Capital area and suburbanization in the spatial structure of capital area. With rapid growth, urbanization and industrialization are unsystematic, and growth inequality between regions caused negative effects such as discordant centralization and decentralization, fluctuating land value, and gap between living conditions. Accordingly, this study analyzed urban spatial indexes by the self-governed body in the capital area such as Seoul, Incheon, and Gyeonggi province for the analysis of the regional inequality phenomenon. We examined the characteristics of temporal and spatial changes in urban spatial structure in the capital area by utilizing the distribution pattern and density of city indexes such as population, employment, etc, and then drew the commonality of those factors through factor analysis. We evaluated the drawn results through the city standard index by each city, conducted factor score analysis, and identified the interaction between each factor and Housing Purchase Price Composite Indices index, housing rent price index(Housing Jeonse Price Composite Indices), land price fluctuation rate, diffusion ratio of house, and financial independence.

Characterization of directional coupling optical switch at High frequency (고주파에서 방향성결합형 광 스위치의 출력 특성변화)

  • 강기성;소대화
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.264-268
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    • 1996
  • Directional coupling optical switch which on the LiNbO$_3$ substrate is fabricated by using proton exchange method and self-aligned method. Proton exchange of proton diffusion method was applied to pattern a waveguide on LiNbO$_3$ substrate. The annealing at 400[$^{\circ}C$] was caroled out to control waveguide width and depth. The process of proton exchange was done at 150[$^{\circ}C$] for 120[min], 200[$^{\circ}C$] for 60[min] and annealing process was done at 400[$^{\circ}C$] for 90[min], 400[$^{\circ}C$] for 60[min]. The high speed directional coupling optical switch has very good figures of merits:the measured high frequency power were achieved.

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A Research Framework for the Success Factors of Information

  • Yoo, Sangjin;Soongoo, I-Iong
    • Journal of Korea Society of Industrial Information Systems
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    • v.3 no.1
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    • pp.117-139
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    • 1998
  • This study is intended to identify the factors affecting the successful information warehouse (IW) implementation through the technology acceptance model. As the IW has played an important role with the organizations, it has become a strategic management tool. However, because the building of an IWS requires a great amound of financing and a multi-period, managers should consider identifying the variables as a predictor of IWS success. The related research areas, such as TAM , TRA, and innovation diffusion theory, and previous research associated with the EWS success factors are reviewed in this paper. Based on the hypotheses presented , the study will empirically test the relationships between six external variable-user involvement, computer self-efficacy, OLAP characteristics, problem difficulty , user training and top management support-and system utilization via user's perceptions of ease of use, unusefulness. This study semmes to be a first attempt in this research area, and its results will provide general guidclines for IWS project managers to enhancement the like hood of system succes.

The Carrier Diffusion Modeling of CSP-DH Semiconductor Laser Structures (CSP-DH 구조 반도체 레이저의 캐리어 확산 방정식을 위한 모델링)

  • Lee, S.T.;Jeon, H.S.;Lee, C.Y.;Um, K.Y.;Yoon, J.W.;Yoon, S.B.;Oh, H.S.
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.469-471
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    • 1988
  • The basic modeling is analyzed on the optoelectronic properties of CSP-DH laser structure using self-consistent calculation of optical field and the electron-hole distribution in the active region. Laser properties is modelled include gain profile, threshold, near field and far field pattern. This new characterization is allowed for consideration such as carrier spatial hole burning due to strong optical fields which stimulate recombination.

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