• Title/Summary/Keyword: Sequential procedure

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Development and Applications of a Chemical Method for Sequential Analysis of Reducing Oligosaccharides

  • Hong, Seon-Pyo;Lee, Yong-Moon;Hiroshi-Nakamura
    • Archives of Pharmacal Research
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    • v.20 no.2
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    • pp.184-190
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    • 1997
  • A new method based on the chemical reaction has been devised for the sequential analysis of reducing oligosaccharides using 8-amino-2-naphthalenesulfonic acid (ANS), a fluorescent precolumn derivatization reagent for reducing saccharides. The procedure established includes 1) the derivatization of a reducing oligosaccharide to produce a Schiff base, 2) the reduction of the base with sodium cyanoborohydride $(NaBH_3/CN), 3)$ the methoxycarbonylation of the resultant secondary amino group, 4) the cleavage of the glycoside bond next to the reducing end, based on the intramolecular acid hydrolysis by the action of a sulfonic acid group of the ANS derivative, 5) the identification of the liberated reducing end by high-performance liquid chromatography (HPLC), and finally 6) the recovery of the resultant oligosaccharide fragment from the cleavage reaction mixture. The extensive examination of the conditions for the sequential analysis of reducing oligosaccharides resulted in the procedure of simplicity , high selectivity and high recovery. This procedure was found to be useful for the sequential analysis of di-, tri- and tetrasaccharides.

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A Method of Design for Sequential Control Systems (시이퀀스 제어계통의 설계법)

  • Hwang, Chang-Sun
    • 전기의세계
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    • v.18 no.6
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    • pp.33-45
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    • 1969
  • The purpose of this paper is design the most important part of sequential control systems, that is, command-treatment part, from the signal-transformation point of view. An orderly procedure is developed by which for sequential control systems the experimental design method can be reduced to the rational design method. Important in this procedure are: 1. To make total block diagram of sequential control systems by determining input and output signals of command-treatment part. 2. To partition over-all block diagram by observing each output signal. 3. To design concretely minimum block diagram by using the operational block diagram. By applying the method for partitioning the circuit to the design, the design method for sequential control systems is organized and done rationally without the aid of experiece.

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Some Properties of Sequential Point Estimation of the Mean

  • Choi, Ki-Heon
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.3
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    • pp.657-663
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    • 2005
  • Under the minimum risk point estimation formulation of Robbins(1959), we consider the sequential point estimation problem for normal population $N({\theta},\;{\theta})$ with unknown parameter ${\theta}$. In the case of completely unknown ${\theta}$, Stein's(1945) two-stage procedure is known to enjoy the consistency property, but it is not even first-order efficient. In the case when ${\theta}>{\theta}_L\;where\;{\theta}_L(>0)$ is known, the revised two-stage procedure is shown to enjoy all the usual second-order properties.

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Fixed-accuracy confidence interval estimation of P(X > c) for a two-parameter gamma population

  • Zhuang, Yan;Hu, Jun;Zou, Yixuan
    • Communications for Statistical Applications and Methods
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    • v.27 no.6
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    • pp.625-639
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    • 2020
  • The gamma distribution is a flexible right-skewed distribution widely used in many areas, and it is of great interest to estimate the probability of a random variable exceeding a specified value in survival and reliability analysis. Therefore, the study develops a fixed-accuracy confidence interval for P(X > c) when X follows a gamma distribution, Γ(α, β), and c is a preassigned positive constant through: 1) a purely sequential procedure with known shape parameter α and unknown rate parameter β; and 2) a nonparametric purely sequential procedure with both shape and rate parameters unknown. Both procedures enjoy appealing asymptotic first-order efficiency and asymptotic consistency properties. Extensive simulations validate the theoretical findings. Three real-life data examples from health studies and steel manufacturing study are discussed to illustrate the practical applicability of both procedures.

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
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    • v.11 no.1
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    • pp.17-22
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    • 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.

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Sequential Test for Parameter Changes in Time Series Models

  • Lee Sangyeol;Ha Jeongcheol
    • Proceedings of the Korean Statistical Society Conference
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    • 2001.11a
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    • pp.185-189
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    • 2001
  • In this paper, we consider the problem of testing for parameter changes in time series models based on a sequential test. Although the test procedure is well-established for the mean and variance change, a general parameter case has not been discussed in the literature. Therefore, we develop a sequential test for parameter changes in a more general framework.

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SEQUENTIAL CONFIDENCE INTERVALS WITH ${\beta}-PROTECTION$ IN A NORMAL DISTRIBUTION HAVING EQUAL MEAN AND VARIANCE

  • Kim, Sung-Kyun;Kim, Sung-Lai;Lee, Young-Whan
    • Journal of applied mathematics & informatics
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    • v.23 no.1_2
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    • pp.479-488
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    • 2007
  • A sequential procedure is proposed in order to construct one-sided confidence intervals for a normal mean with guaranteed coverage probability and ${\beta}-protection$ when the normal mean and variance are identical. First-order asymptotic properties on the sequential sample size are found. The derived results hold with uniformity in the total parameter space or its subsets.

On the Bayesian Sequential Estiamtion Problem in k-Parameter Exponential Family

  • Yoon, Byoung-Chang;Kim, Jea-Joo
    • Journal of the Korean Statistical Society
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    • v.10
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    • pp.128-139
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    • 1981
  • The Bayesian sequential estimation problem for k parameters exponential families is considered using loss related to the Fisher information. Tractable expressions for the Bayes estimator and the posterior expected loss are found, and the myopic or one-step-ahead stopping rule is defined. Sufficient conditions are given for optimality of the myopic procedure, and the myopic procedure is shown to be asymptotically optimal in all cases considered.

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Economic Selection of the Optimal Process Mean Using Sequential Inspection to Reduce the Effect of Measurement Errors (측정오차를 고려한 최적 공정평균의 경제적 설정 - 축차검사의 활용)

  • Park, Hwan-Su;Chang, Young-Soon
    • Journal of Korean Society for Quality Management
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    • v.34 no.2
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    • pp.12-21
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    • 2006
  • This paper considers the problem of selecting the most profitable process mean for production processes where measurement errors exist in inspection systems. For such situations, a sequential inspection procedure is proposed to reduce measurement errors. The decision to accept, reject, or take an additional inspection of an item is made at every measurement point until the number of repeated measurements reaches its upper bound. An expected profit model is constructed and the optimal process mean, the cut-off values, and the upper bound of the number of repeated measurements are obtained when accepted(rejected) items are sold at regular(reduced) price. A numerical study is performed to investigate the performance of the proposed procedure.