• Title/Summary/Keyword: Critical Theory

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A Study on the Framework of the IS Department Innovation (정보시스템 부서혁신의 이론체계 정립을 위한 연구)

  • Chang, Yun-Hi;Lee, Jae-Beom;Nam, Ki-Chan
    • Asia pacific journal of information systems
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    • v.9 no.3
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    • pp.25-46
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    • 1999
  • Today the role of information systems directly affects the goals and operations of companies and is being strategic. Most of Information System Departments (ISD), however, have been losing the credibility due to their failure to respond effectively to their counterparts in the rapidly changing environment. The purpose of this research is to propose a theoretical framework which systematically studies the innovation of ISD. It is intended to understand the critical factors which have an effect on each level of ISD innovation process. It is also intended to understand the performance of ISD innovation through the innovation process. Besides, we try to clarify the conceptual difference between IS innovation, Information Technology innovation, and ISD Innovation. As a result, we propose the structural model for ISD innovation research by analyzing the innovation theory and previous IS innovation studies.

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The Stability of Composite Pipes Conveying Fluid (유체유동에 의한 복합재료 파이프의 안정성 연구)

  • 최재운;송오섭
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.904-910
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    • 2001
  • Static and oscillatory loss of stability of composite pipes conveying fluid is investigated. The theory of thin walled beams is applied and transverse shear, rotary inertia, primary and secondary warping effects are incorporated. The governing equations and the associated boundary conditions are derived through Hamilton's variational principle. The governing equations and the associated boundary conditions are transferred to eigenvalues problem which provides the information about the dynamic characteristics of the system. Numerical analysis is performed by using extended Gelerkin method. Critical velocity of fluid is investigated by increasing fiber angle and mass ratio of fluid to pipe including fluid.

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Self-excited Vibration Characteristics of Cylindrical Composit Shell subject to Thermal Stresses in Supersonic Flow (초음속 유동에서 열응력을 받는 원통형 복합적층 쉘의 자려진동 특성)

  • Oh, Il-Kwon;Lee, In;Koo, Kyo-Nam
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.897-903
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    • 2001
  • The supersonic flutter analysis of cylindrical composite panels subject to thermal stresses has been performed using layerwise nonlinear finite elements. The geometric nonlinear finite elements of cylindrical shells are formulated using hamilton's principle with von Karman strain-displacement relationship. Hans Krumhaar's modified supersonic piston theory is appled to calculate aerodynamic loads for the panel flutter analysis. The present results show that the critical dynamic pressure of cylindrical panels under compressive thermal stresses can be dramatically reduced. The margin of aerothermoelastic stability considering thermal and aerodynamic coupling should be verified in the structural design of launch vehicles and high speed aircrafts.

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The effect of Fe2O3 nanoparticles instead cement on the stability of fluid-conveying concrete pipes based on exact solution

  • Nouri, Alireza Zamani
    • Computers and Concrete
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    • v.21 no.1
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    • pp.31-37
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    • 2018
  • This paper deals with the stability analysis of concrete pipes mixed with nanoparticles conveying fluid. Instead of cement, the $Fe_2O_3$ nanoparticles are used in construction of the concrete pipe. The Navier-Stokes equations are used for obtaining the radial force of the fluid. Mori-Tanaka model is used for calculating the effective material properties of the concrete $pipe-Fe_2O_3$ nanoparticles considering the agglomeration of the nanoparticles. The first order shear deformation theory (FSDT) is used for mathematical modeling of the structure. The motion equations are derived based on energy method and Hamilton's principal. An exact solution is used for stability analysis of the structure. The effects of fluid, volume percent and agglomeration of $Fe_2O_3$ nanoparticles, magnetic field and geometrical parameters of pipe are shown on the stability behaviour of system. Results show that considering the agglomeration of $Fe_2O_3$ nanoparticles, the critical fluid velocity of the concrete pipe is decreased.

Thermal stability analysis of temperature dependent inhomogeneous size-dependent nano-scale beams

  • Bensaid, Ismail;Bekhadda, Ahmed
    • Advances in materials Research
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    • v.7 no.1
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    • pp.1-16
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    • 2018
  • Thermal bifurcation buckling behavior of fully clamped Euler-Bernoulli nanobeam built of a through thickness functionally graded material is explored for the first time in the present paper. The variation of material properties of the FG nanobeam are graded along the thickness by a power-law form. Temperature dependency of the material constituents is also taken into consideration. Eringen's nonlocal elasticity model is employed to define the small-scale effects and long-range connections between the particles. The stability equations of the thermally induced FG nanobeam are derived via the principal of the minimum total potential energy and solved analytically for clamped boundary conditions, which lead for more accurate results. Moreover, the obtained buckling loads of FG nanobeam are validated with those existing works. Parametric studies are performed to examine the influences of various parameters such as power-law exponent, small scale effects and beam thickness on the critical thermal buckling load of the temperature-dependent FG nanobeams.

Buckling of laminated composite plates with elastically restrained boundary conditions

  • Kouchakzadeh, Mohammad Ali;Rahgozar, Meysam;Bohlooly, Mehdi
    • Structural Engineering and Mechanics
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    • v.74 no.5
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    • pp.577-588
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    • 2020
  • A unified solution is presented for the buckling analysis of rectangular laminated composite plates with elastically restrained edges. The plate is subjected to biaxial in-plane compression, and the boundary conditions are simulated by employing uniform distribution of linear and rotational springs at all edges. The critical values of buckling loads and corresponding modes are calculated based on classical lamination theory and using the Ritz method. The deflection function is defined based on simple polynomials without any auxiliary function. The verifications of the current study are carried out with available combinations of classic boundary conditions in the literature. Through parametric study with a wide range of spring factors with some classical as well as some not classical boundary conditions, competency of the present model of boundary conditions is proved.

A study on the Social Consciousness Education Approach to Rural Community Development movement (농촌지역사회개발 운동의 사회의식화 교육적 접근)

  • Kim, Tae-Ho
    • Journal of Agricultural Extension & Community Development
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    • v.4 no.1
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    • pp.15-27
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    • 1997
  • This paper reviews the concept and limits of rural community development, examines the relation between consciousness education and movement, and suggests the model of social consciousness education to rural community movement. Since consciousness education is closely related to social movement methodologically, organizational and systematic community development movements for re-structuring the urban-oreiented policies and education which back up them be followed as natural consequence. Based upon the results of this study, the new paradigm is suggested. As shown in the model, new understanding of urban-rural continuum theory, new roles and concept of social consciousness education should be emphasized to solve the contemporary rural community problems. The organizational community development movement for the rural-oriented policy should be an essential process, and peoples' re-orientation, such as 'breaking stereotype', 'assumming a critical thinking toward social reality' etc., is the indispensible background of successful movement.

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Electric Resistance of Gold Thin Film (금박막의 전기저항특성)

  • 박기수;정기형
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.8 no.2
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    • pp.1-5
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    • 1971
  • The resistances of gold thin film are measured as a function of thickness and temperature(300$^{\circ}$k~420$^{\circ}$k). In this paper, the experimental results are analysed using the theory which had been proposed by Sondheimer and Neugebauer and it is shown that the temperature coefficient of resistance of gold thin film become meatily zero at the value of thickness of about 45$\AA$ and its critical thickness is about 60$\AA$.

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Novelistic Mimesis; or, Modalities of Cultural Modernity

  • Yang, Yu-Mi
    • English Language & Literature Teaching
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    • v.13 no.4
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    • pp.193-210
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    • 2007
  • This essay is an attempt to give a theoretical articulation of novelistic mimesis as the narrative form of modernity. With the passage to modernity, what assumes the locus of the symbolic authority is no longer God, Father, or tradition, but the cultural gaze or the ego-ideal. At the same time, this gaze paradoxically coalesces with the "spectacle of the world," on the side of the reified "other": the gaze is both the desexualized ego-ideal and its instantaneous transmogrification and resexualization in the opaque world of objects. The imaginary ego or the eye on the side of the subject of representation is held at abeyance in a state of perpetual fascination and desperation in relation to the gaze as the world of "others," which lies always at one remove from the purview of the imaginary ego. This understanding of the inadequation of the ego to the cultural gaze of the reified world provides a critical fulcrum upon which I base my theory of the modern narrative mimesis as the "perverse" field of spatial arrangement, in which the split of the subjectivity into the imaginary ego and the ego-ideal is suspended over the phantasmatic world of bodies and territories.

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Angular Spectrum of the Spontaneous Emission from Dye Molecules Near a Boundary

  • Choi, Hyun-Ho;Kim, Hyoung-Joo;Noh, Jae-Woo;Park, Dae-Yoon;Jhe, Won-Ho
    • Journal of the Optical Society of Korea
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    • v.6 no.1
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    • pp.1-4
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    • 2002
  • We studied experimentally the angular spectrum of the light emitted from dye Molecules near a plane boundary. It is confirmed that the molecules near the boundary can emit light into the evanescent wave mode, and the light emission with the angle greater than the critical angle is detected with good accuracy. The angular spectrum of the spontaneous radiation is measured, and the spectrum shows contributions from the molecules both near and far away from the boundary. The polarization dependence and the pumping angle dependence are also measured. The experimental results are in good agreement with quantum theory.