• 제목/요약/키워드: Scale Parameter

검색결과 1,280건 처리시간 0.026초

Noninformative Priors for the Common Scale Parameter in the Inverse Gaussian Distributions

  • Kang, Sang-Gil
    • Journal of the Korean Data and Information Science Society
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    • 제15권4호
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    • pp.981-992
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    • 2004
  • In this paper, we develop the noninformative priors for the common scale parameter in the inverse gaussian distributions. We developed the first and second order matching priors. Next we revealed that the second order matching prior satisfies a HPD matching criterion. Also we showed that the second order matching prior matches alternative coverage probabilities up to the second order. It turns out that the one-at-a-time reference prior satisfies a second order matching criterion. Some simulation study is performed.

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Estimation of the Scale Parameter in the Weibull Distribution Based on the Quasi-range

  • Woo, Jung-Soo;Lee, Kgoang-Ho
    • Journal of the Korean Statistical Society
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    • 제12권2호
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    • pp.69-80
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    • 1983
  • The purpose of this paper is to obtain representation of the mathematical special functions and the numerical values of the mean square errors for the quasi-ranges in random small smaples ($n \leq 30$) from the Weibull distribution with a shape and a scale parameters, and to estimate the scale parameter by use of unbiased estimator based on the quasi-range. It will be shown that the jackknife estimator of the range is worse than the range of random samples from the given distribution in the sense of the mean square error.

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표면 거칠기 계수 Rs를 이용한 암석 절리면 전단강도 모델 (Modelling of Rock Joint Shear Strength Using Surface Roughness Parameter, Rs)

  • 이석원;배석일;이인모
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.73-80
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    • 2001
  • The shear strength of jointed rock is influenced by effective normal stress, joint wall compressive strength, joint roughness and so on. Since joint roughness makes considerable influences on shear strength of jointed rock, many studies tried to get quantitative joint roughness parameter. Until now, Joint Roughness Coefficient, JRC proposed by Barton has been prevalently used as a rock joint roughness parameter In spite of its disadvantages. In this study, a quantification of rock joint roughness is performed using surface roughness parameter, Rs. Proposed method is applied to rock core specimens, field joint surfaces, and JRC profiles. The scale of fluctuation is introduced to extend the suggested method to the large scale field joint surface roughness. Based on the quantification of joint surface roughness, joint shear tests are performed with the portable shear box. The relationship between joint surface roughness and joint shear strength is investigated and finally, a rock joint shear strength equation is derived from these results. The equation has considerable credibility and originality in that it is obtained from laboratory tests and expressed with quantified parameter.

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로드리스 실린더의 수명 특성에 관한 연구 (A Study on the Life Characteristic of Rodless Cylinder)

  • 이충성;임재학;강보식
    • 드라이브 ㆍ 컨트롤
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    • 제12권1호
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    • pp.21-27
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    • 2015
  • Pneumatic cylinders are classified into rod-type pneumatic cylinders and rodless pneumatic cylinders depending on the presence of the rod. Rodless cylinders have a constant area and have no deflection. Rodless cylinders are widely used in automatic systems requiring high-speed performance and high-precision transportation. However, the research of the pneumatic cylinder has been focused on the structure and life characteristics. In this research, aging characteristics and shape parameter analysis which are related to the lifetime were investigated. By conducting the lifetime tests with two different materials for the transfer plate, the failure mode and lifetime characteristics were analyzed. By the Anderson-Darling (A-D) verification based on the complete data set, the analysis results of lifetime distribution, shape parameter, and scale parameter were provided.

Effect of dimensionless nonlocal parameter: Vibration of double-walled CNTs

  • Hussain, Muzamal;Asghar, Sehar;Khadimallah, Mohamed Amine;Ayed, Hamdi;Alghamdi, Sami;Bhutto, Javed Khan;Mahmoud, S.R.;Tounsi, Abdelouahed
    • Computers and Concrete
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    • 제30권4호
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    • pp.269-276
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    • 2022
  • In this paper, frequency vibrations of double-walled carbon nanotubes (CNTs) has been investigated based upon nonlocal elastic theory. The inference of small scale is being perceived by establishing nonlocal Love shell model. The wave propagation approach has been operated to frame the governing equations as eigen value system. An innovational nonlocal model to examine the scale effect on vibrational behavior of armchair, zigzag and chiral of double-walled CNTs. An appropriate selection of material properties and nonlocal parameter has been considered. The influence of dimensionless nonlocal parameter has been studied in detail. The dominance of end condition via nonlocal parameter is explained graphically. The results generated furnish the evidence regarding applicability of nonlocal shell model and also verified by earlier published literature.

Fundamental parameters of nanoporous filtration membranes

  • Wei Li;Xiaoxu Huang;Yongbin Zhang
    • Membrane and Water Treatment
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    • 제14권3호
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    • pp.115-120
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    • 2023
  • The design theory for nanoporous filtration membranes needs to be established. The present study shows that the performance and technical advancement of nanoporous filtration membranes are determined by the fundamental parameter I (in the unit Watt1/2) which is formulated as a function of the shear strength of the liquid-pore wall interface, the radius of the filtration pore, the membrane thickness, and the bulk dynamic viscosity of the flowing liquid. This parameter determines the critical power loss on a single filtration pore for initiating the wall slippage, which is important for the flux of the membrane. It also relates the membrane permeability to the power cost by the filtration pore. It is shown that for biological cellular membranes its values are on the scale 1.0E-8Watt1/2, for mono-layer graphene membranes its values are on the scale 1.0E-9Watt1/2, and for nanoporous membranes made of silica, silicon nitride or silicon carbonized its values are on the scale 1.0E-5Watt1/2. The scale of the value of this parameter directly measures the level of the performance of a nanoporous filtration membrane. The carbon nanotube membrane has the similar performance with biological cellular membranes, as it also has the value of I on the scale 1.0E-8Watt1/2.

Approximate MLE for the Scale Parameter of the Weibull Distribution with Type-II Censoring

  • Kang, Suk-Bok;Kim, Mi-Hwa
    • Journal of the Korean Data and Information Science Society
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    • 제5권2호
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    • pp.19-27
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    • 1994
  • It is known that the maximum likelihood method does not provide explicit estimator for the scale parameter of the Weibull distribution based on Type-II censored samples. In this paper we provide an approximate maximum likelihood estimator (AMLE) of the scale parameter of the Weibull distribution with Type-II censoring. We obtain the asymptotic variance and simulate the values of the bias and the variance of this estimator based on 3000 Monte Carlo runs for n = 10(10)30 and r,s = 0(1)4. We also simulate the absolute biases of the MLE and the proposed AMLE for complete samples. It is found that the absolute bias of the AMLE is smaller than the absolute bias of the MLE.

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감마분포 처리의 최대 척도모수 선택에 관한 제거형 이단 선택방법 (A two-stage elimination type procedure for selecting the largest gamma scale parameter)

  • 김순기
    • 응용통계연구
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    • 제1권2호
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    • pp.27-33
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    • 1987
  • 감마분포에 따르는 K($\geq$2)개의 처리들 중에서 최대 척도모수를 갖는 처리를 선택하는 제거형 이단 선택방법을 제안하고 주어진 $(\delta^*, p^*)$에 대하여 Kim(1985)이 제안한 선택확률의 하한을 만족할때 설계상수(nr, mr, c)와 총실험횟수의 평균을 Monte Carlo 방법으로 구하였다. 또한 총실험횟수를 작게한다는 점에서 일단 선택방법보다 유용함을 밝혔다.

A new four-unknown refined theory based on modified couple stress theory for size-dependent bending and vibration analysis of functionally graded micro-plate

  • Amar, Lemya Hanifi Hachemi;Kaci, Abdelhakim;Yeghnem, Redha;Tounsi, Abdelouahed
    • Steel and Composite Structures
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    • 제26권1호
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    • pp.89-102
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    • 2018
  • This work investigates a novel plate formulation and a modified couple stress theory that introduces a variable length scale parameter is presented to discuss the static and dynamic of functionally graded (FG) micro-plates. A new type of third-order shear deformation theory of Reddy that use only 4 unknowns by including undetermined integral variables is proposed in this study. The equations of motion are derived from Hamilton's principle. Analytical solutions are obtained for a simply supported micro-plate. Numerical examples are presented to examine the effect of the length scale parameter on the responses of micro-plates. The obtained results are compared with the previously published results to demonstrate the correctness of the present formulation.

순서를 갖는 척도모수들의 사전정보 하에 k-모집단 와이블분포의 베이지안 모수추정 (Bayesian Estimation of k-Population Weibull Distribution Under Ordered Scale Parameters)

  • 손영숙;김성욱
    • 응용통계연구
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    • 제16권2호
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    • pp.273-282
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    • 2003
  • 순서화된 척도모수들의 사전정보를 가지는 k-모집단 와이블분포의 모수추정을 위한 베이지안방법이 제시된다. 모수추정은 깁스샘플링에 의해서 이루어지며, 특히 깁스샘플러에서 형태모수의 조건부 사후분포는 로그-오목함수이므로 적응기각표집(Adaptive Rejection Sampling: ARS)방법에 의해 모수생성을 하였다. 논의된 모수추정법을 전기 절연유체 고장시간자료에 적용하여 척도모수의 순서화정보를 반영한 경우와 그렇지 않은 경우를 비교하였다.