• Title/Summary/Keyword: numerical comparisons

Search Result 687, Processing Time 0.023 seconds

A Bayesian Test Criterion for the Multivariate Behrens-Fisher Problem

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
    • /
    • v.28 no.1
    • /
    • pp.107-124
    • /
    • 1999
  • An approximate Bayes criterion for multivariate Behrens-Fisher problem is proposed and examined. Development of the criterion involves derivation of approximate Bayes factor using the imaginary training sample approach introduced by Speigelhalter and Smith (1982). The criterion is designed to develop a Bayesian test, so that it provides an alternative test to other tests based upon asymptotic sampling theory (such as the tests suggested by Bennett(1951), James(1954) and Yao(1965). For the derived criterion, numerical studies demonstrate routine application and give comparisons with the classical tests.

  • PDF

A Bayes Criterion for Testing Homogeneity of Two Multivariate Normal Covariances

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
    • /
    • v.27 no.1
    • /
    • pp.11-23
    • /
    • 1998
  • A Bayes criterion for testing the equality of covariance matrices of two multivariate normal distributions is proposed and studied. Development of the criterion invloves calculation of Bayes factor using the imaginary sample method introduced by Spiegelhalter and Smith (1982). The criterion is designed to develop a Bayesian test criterion, so that it provides an alternative test criterion to those based upon asymptotic sampling theory (such as Box's M test criterion). For the constructed criterion, numerical studies demonstrate routine application and give comparisons with the traditional test criteria.

  • PDF

A Study on Excavation Responses of Underground Openings for Radioactive Waste Disposal (굴착으로 인한 방사성폐기물 지하처분공동의 거동변화)

  • 김선훈;김대홍;최규섭;김진웅
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1992.10a
    • /
    • pp.174-179
    • /
    • 1992
  • In this paper a discussion is presented about excavation responses of underground openings for radioactive waste disposal. The effects of excavation methods, stress redistribution, thermal change, and backfill materials are reviewed. Comparisons of computational models for discontinuous reek masses and discussions on numerical simulation techniques for the excavation of underground openings are also described. Finally, the application of the CAD system to the planning, design and construction of underground openings fop radioactive waste disposal is introduced.

  • PDF

Multivariate Control Charts for Several Related Quality Characteristics

  • Chang, Duk-Joon;Shin, Jae-Kyoung
    • Journal of the Korean Data and Information Science Society
    • /
    • v.16 no.2
    • /
    • pp.467-476
    • /
    • 2005
  • Multivariate control charts for monitoring mean vector of several related quality variables with combine-accumulate approach and accumulate-combine apprach were investigated. Shewhart chart is also proposed to compare the performances of CUSUM and EWMA charts. Numerical comparisons show that CUSUM and EWMA charts are more efficient than Shewhart chart for small or moderate shifts, and multivariate charts based on accumulate- combine approach is more efficient than corresponding multivariate charts based on combine-accumulate approach.

  • PDF

A Study on the Performance of Multiple Trellis Code Differential MPSK over Rician and Rayleigh Fading Channels (페이딩 채널하에서의 다중 Trellis 부호화된 차동 M진 PSK방식의 오율 특성에 관한 연구)

  • 김한규;김평재;김영권
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.30A no.11
    • /
    • pp.11-20
    • /
    • 1993
  • In this paper, the asymtotic performance of a multiple trellis coded differential MPSK modulation over a satellite land mobile communication channel characterized by additive white Gaussian noise (AWGN) and fading is presented. Simple formulas for the bit error probability are derived for systems using differential MTCM over Rician and Rayleigh fading channel. Also are given numerical results which are more indicative of the actual system performance. Finally, the comparisons with results previously obtained for the uncoded and conventional trellis coded modulation are provided.

  • PDF

A Batch Sequential Sampling Scheme for Estimating the Reliability of a Series/Parallel System

  • Enaya, T.;Rekab, L.;Tadj, L.
    • International Journal of Reliability and Applications
    • /
    • v.11 no.1
    • /
    • pp.17-22
    • /
    • 2010
  • It is desired to estimate the reliability of a system that has two subsystems connected in series where each subsystem has two components connected in parallel. A batch sequential sampling scheme is introduced. It is shown that the batch sequential sampling scheme is asymptotically optimal as the total number of units goes to infinity. Numerical comparisons indicate that the batch sequential sampling scheme performs better than the balanced sampling scheme and is nearly optimal.

  • PDF

Bayesian Multiple Comparison of Bivariate Exponential Populations based on Fractional Bayes Factor

  • Cho, Jang-Sik;Cho, Kil-Ho;Choi, Seung-Bae
    • Journal of the Korean Data and Information Science Society
    • /
    • v.17 no.3
    • /
    • pp.843-850
    • /
    • 2006
  • In this paper, we consider the Bayesian multiple comparisons problem for K bivariate exponential populations to make inferences on the relationships among the parameters based on observations. And we suggest the Bayesian procedure based on fractional Bayes factor when noninformative priors are applied for the parameters. Also, we give a numerical examples to illustrate our procedure.

  • PDF

A Short Kinetic Mechanism for Premixed Flames of Aromatic Compound : Benzene (방향족 화합물 화염의 축소 반응 메카니즘 개발 : 벤젠)

  • Lee, Ki Yong
    • 한국연소학회:학술대회논문집
    • /
    • 2015.12a
    • /
    • pp.161-164
    • /
    • 2015
  • A short kinetic mechanism for premixed benzene/air flames was developed with a reduction method of Simulation Error Minimization Connectivity Method(SEM-CM). It consisted of 38 species and 336 elementary reactions. Flame speeds were calculated and compared with those from full mechanisms and experiments of other researcher. Those comparisons are in good agreement between the full mechanism and the short mechanism at high pressure condition. In numerical work the running time with the short mechanism was over 10 times faster than one with the full mechanism.

  • PDF

SIMULATION OF EXPERIMENTAL VISUALIZATION METHODS FOR COMPUTATIONAL FLUID DYNAMICS RESEARCH

  • TAMURA Y.;FUJII K.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 1995.04a
    • /
    • pp.44-68
    • /
    • 1995
  • In the present paper, visualization techniques in fluid dynamic experiments such as Schlieren photograph are numerically simulated so that the same output as the experimental flow visualization can be obtained from the computed results for the fair comparison. Numerical methods to simulate optical visualizations, that are Schlieren photograph, shadowgraph and interferogram, are considered. Some examples of pictures obtained by the present methods show the importance of the simulations of visualization techniques for the correct comparisons of the computations and experiments.

  • PDF

Performance Analysis of LAN Interworking Unit for Capacity Dimensioning of Internet Access Links

  • Park, Chul-geun;Han, Dong-hwan
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.4B
    • /
    • pp.692-699
    • /
    • 2000
  • We build and analyze some types of queueing model to discuss capacity dimensioning of access links of a LAN interworking unit connected to the Internet backbone network. We assume that the IWU has a FIFO buffer to transmit IP packets to the Internet through the backbone. In order to analyze the system, we use a Poisson process and an MMPP process as input traffic models of IP packets and we use a general service time distribution as a service time model. But we use both an exponential service time and a deterministic service time in numerical examples for simple and efficient performance comparisons. As performance measures, we obtain the packet loss probability and the mean packet delay. We present some numerical results to show the effect of arrival rate, buffer size and link capacity on packet loss and mean delay.

  • PDF