• 제목/요약/키워드: power-law function

검색결과 281건 처리시간 0.031초

MEASURING MORBIDITY : AN APPROACH USING POWER FUNCTIONS

  • Janssens, Gerrit K.
    • 한국경영과학회지
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    • 제13권2호
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    • pp.72-77
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    • 1988
  • Subjective scoring by different groups on different status of morbidity are compared to objective data obtained from legal awards. A power law is tested between subjective and objective scores. Regression analysis by means of a power function provides a measure of consistency in its regression coefficient. Power functions fitting also leads to a justified use of geometric averaging of individual scores into group scores.

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국제화 시대의 경찰작용 통제법리에 관한 연구 -경찰권발동의 한계를 중심으로- (A Study on the Regulative Principle of Law in Respect to Police Function in Internationalized Age - Centering on Limitation to Police Authority Exercise -)

  • 오태곤;김동복
    • 한국콘텐츠학회논문지
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    • 제5권3호
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    • pp.63-71
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    • 2005
  • 경찰은 위험방지의 영역에 있어서 경찰권을 발동할 책무를 가지지만, 위험방지를 위해 개입을 하여야만 하는지의 여부, 어떠한 개입 및 어느 정도의 개입을 하여야만 하는가에 관하여 재량에 의하여 결정할 수 있다. 그러한 재량에 따른 경찰의 조치는 침해적인 명령 강제를 내용으로 하기 때문에 국민의 권리를 침해하기 마련이다. 따라서 경찰권의 발동에는 법치주의의 원리에 따른 법률유보의 원칙에 따라 필연적으로 법적 통제장치가 따라야 찬다. 본 연구는 경찰작용의 통제법리로서 경찰권 발동의 한계를 중심으로 공공의 안녕과 질서를 유지하면서도 국민의 자유와 권리를 최대한 보장할 수 있는 합리적인 방안을 강구하여 경찰작용의 바람직한 방향을 모색하고자 한다.

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Electro-elastic analysis of a sandwich thick plate considering FG core and composite piezoelectric layers on Pasternak foundation using TSDT

  • Mohammadimehr, Mehdi;Rostami, Rasoul;Arefi, Mohammad
    • Steel and Composite Structures
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    • 제20권3호
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    • pp.513-543
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    • 2016
  • Third order shear deformation theory is used to evaluate electro-elastic solution of a sandwich plate with considering functionally graded (FG) core and composite face sheets made of piezoelectric layers. The plate is resting on the Pasternak foundation and subjected to normal pressure. Short circuited condition is applied on the top and bottom of piezoelectric layers. The governing differential equations of the system can be derived using Hamilton's principle and Maxwell's equation. The Navier's type solution for a sandwich rectangular thick plate with all edges simply supported is used. The numerical results are presented in terms of varying the parameters of the problem such as two elastic foundation parameters, thickness ratio ($h_p/2h$), and power law index on the dimensionless deflection, critical buckling load, electric potential function, and the natural frequency of sandwich rectangular thick plate. The results show that the dimensionless natural frequency and critical buckling load diminish with an increase in the power law index, and vice versa for dimensionless deflection and electrical potential function, because of the sandwich thick plate with considering FG core becomes more flexible; while these results are reverse for thickness ratio.

Buckling analysis of functionally graded plates using HSDT in conjunction with the stress function method

  • Bakoura, Ahmed;Bourada, Fouad;Bousahla, Abdelmoumen Anis;Tounsi, Abdeldjebbar;Benrahou, Kouider Halim;Tounsi, Abdelouahed;Al-Zahrani, Mesfer Mohammad;Mahmoud, S.R.
    • Computers and Concrete
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    • 제27권1호
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    • pp.73-83
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    • 2021
  • In this article, the mechanical buckling analysis of simply-supported functionally graded plates is carried out using a higher shear deformation theory (HSDT) in conjunction with the stress function method. The proposed formulation is variationally consistent, does not use a shear correction factor and gives rise to a variation of transverse shear stress such that the transverse shear stresses vary parabolically through the thickness satisfying the surface conditions without stress of shear. The properties of the plate are supposed to vary across the thickness according to a simple power law variation in terms of volume fraction of the constituents of the material. Numerical results are obtained to study the influences of the power law index and the geometric ratio on the critical buckling load.

Vibration Control of an Axially Moving Belt by a Nonlinear Boundary Control

  • Park, Ji-Yun;Hong, Keum-Shik
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.38.1-38
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    • 2001
  • In this paper, the vibration suppression problem of an axially moving power transmission belt is investigated. The equations of motion of the moving belt is first derived by using Hamilton´s principle for systems with changing mass. The total mechanical energy of the belt system is considered as a Lyapunov function candidate. Using the Lyapunov second method, a nonlinear boundary control law that guarantees the uniform asymptotic stability is derived. The control performance with the proposed control law is simulated. It is shown that a boundary control can still achieve the uniform stabilization for belt systems.

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복소 유사 응력 함수에 의한 타원 강체 함유물을 내포하는 글잎 재료의 응력 해석

  • 김종성;이강용
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.740-743
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    • 1995
  • The analysis model is the power law creep material containing an elliptical rigid inclusion subjected to the arbitrarily directional stress on infinite boundary. The stress analysis is performed using the conformal mapping function and complex pseudo-stress function. The stress distributions near an elliptical rigid inclusion are obtained with various ellipse shapes, strain hardening exponents and directions of applied stress.

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경험자료에 의한 동해안의 지진해일 재해도 평가 (Tsunami Hazard Evaluation for the East Coast of Korea by using Empirical Tsunami Data)

  • 김민규;최인길;강금석
    • 한국지진공학회논문집
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    • 제14권4호
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    • pp.17-22
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    • 2010
  • 본 연구에서는 지진해일에 의한 원자력발전소의 확률론적 안전성 평가를 위하여 필수적으로 도출해야 하는 지진해일 재해도 곡선을 도출하기 위한 연구를 수행하였다. 1900년도 이후에 기록된 동해안에서의 지진해일 기록과 1900년도 이전에 역사지진기록에서 찾을 수 있는 지진해일 기록을 이용하여 지진해일에 의한 최대파고에 대한 재현주기를 산정하고자 하였다. Power law, upper-truncated power law 그리고 지수함수에 의해서 추세선을 작성하였으며 그 결과를 비교하였다. 동해안에서 발생한 지진해일의 기록이 10건 내외에 불과하므로 기록에 의한 지진해일 재해도 곡선추정 연구에 제한이 있으나 국내에는 지진해일의 재해도곡선 추정에 관한 연구가 전무한 현실이므로 지진해일 확률론적 안전성 평가를 위한 초석을 놓은 것으로 판단된다.

PROPERTIES OF DUST IN EARLY-TYPE GALAXIES BASED ON THE ALL-SKY-SURVEY DATA AND NEAR-INFRARED SPECTRA

  • Mori, T.;Oyabu, S.;Kaneda, H.;Ishihara, D.;Yamagishi, M.
    • 천문학논총
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    • 제27권4호
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    • pp.263-264
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    • 2012
  • We present the properties of dust and the near-infrared spectral features in nearby early-type galaxies. The properties of dust are obtained from the AKARI far-infrared all-sky survey diffuse map. The AKARI/IRC is used for the near-infrared spectra. We improve spectral data with the new dark subtraction method on the basis of the knowledge acquired in our laboratory experiments of the engineering-model detector for the IRC. We have succeeded in fitting the continuum by a power-law function and detecting CO and SiO absorption features in early-type galaxy spectra. Comparing the properties of dust and near-infrared spectral features, we find that the power-law slope depends on dust temperature, but not on the dust mass, which suggests that low-luminosity AGNs may contribute to the changes in the power-law slope and dust temperature.

Double Cantilever Beam 방법을 이용한 다결정 알루미나의 Bridging 응력효과 해석 III. 다결정 알루미나의 Bridging 응력분포 (Analysis of bridging Stress Effect of Polycrystlline Aluminas Using Double Cantilever Beam Method)

  • 손기선;이성학;백성기
    • 한국세라믹학회지
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    • 제33권5호
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    • pp.602-615
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    • 1996
  • The purpose of the present study is to investigate the microstructural effect on the R-curve behavior in three aluminas with different grain size distributions by analyzing the bridging stress distribution. The crack opening displacement (COD) according to the distance behind the stationary crack tip was measured using an in situ SEM fracture method. The measured COD values in the fine-grained alumina agreed well with Wiederhorn's sollution while they deviated from Wiederhorn's solution in the two coarse-grained aluminas because of the increase of the crack closure due to the grain interface bridging in the crack wake. A numerical fitting procedure was conducted by the introduction of the power-law relation and the current theoretical model together with the measured COD's in order to obtain the bridging stress distribution. The results indicated that the bridging stress function and the R-curve computed by the current model were consistent with those computed by the power-law relation providing a reliable evidence for the bridging stress analysis of the current model. The strain-softening exponent in the power-law relation n, was calculated to be in the range from 2 to 3 and was closely related to the grain size distribution. Thus it was concluded from the current theoretical model that the grain size distribution affected greatly the bridging stress distribution thereby resulting in the quantitative analysis of microfracture of polycrystalline aluminas through correlating the local-fracture-cont-rolling microstructure.

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Wave propagation investigation of a porous sandwich FG plate under hygrothermal environments via a new first-order shear deformation theory

  • Al-Osta, Mohammed A.
    • Steel and Composite Structures
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    • 제43권1호
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    • pp.117-127
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    • 2022
  • This study investigates the wave propagation in porous functionally graded (FG) sandwich plates subjected to hygrothermal environments. A new simple three-unknown first-ordershear deformation theory (FSDT) incorporating an integral term is utilized in this paper. Only three unknowns are used to formulate the governing differential equation by applying the Hamilton principle. The FG layer of the sandwich plate is modeled using the power-law function with evenly distributed porosities to represent the defects of the manufacturing process. The plate is subjected to nonlinear hygrothermal changes across the thickness. The effects of the power-law exponent, core to thickness ratios, porosity volume, and the relations between volume fraction and wave properties of porous FG plate under the hygrothermal environment are investigated. The results showed that the waves' phase velocities increase linearly with the waves number in the FGM plate. The porosity of the FG materials plate has a noticeable impact on the phase velocity when considering the high ratios of the core layer. It has a negligible effect on small core layers. Finally, it is observed that changing temperatures and moistures do not influence the relationship between the power law and the phase velocity.