• Title/Summary/Keyword: beta distribution

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Design of Bayesian Zero-Failure Reliability Demonstration Test and Its Application (베이지안 신뢰성입증시험 설계와 활용)

  • Kwon, Young Il
    • Journal of Applied Reliability
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    • v.13 no.1
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    • pp.1-10
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    • 2013
  • A Bayesian zero-failure reliability demonstration test method for products with exponential lifetime distribution is presented. Beta prior distribution for reliability of a product is used to design the Bayesian test plan and selecting a prior distribution using a prior test information is discussed. A test procedure with zero-failure acceptance criterion is developed that guarantees specified reliability of a product with given confidence level. An example is provided to illustrate the use of the developed Bayesian reliability demonstration test method.

Enhancement of Sensitivity in Interferometric Biosensing by Using a New Biolinker and Prebinding Antibody

  • Park, Jae-Sook;Lim, Sung-Hyun;Sim, Sang-Jun;Chae, Hee-Yeop;Yoon, Hyun-C.;Yang, Sang-Sik;Kim, Byung-Woo
    • Journal of Microbiology and Biotechnology
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    • v.16 no.12
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    • pp.1968-1976
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    • 2006
  • Recombinant E. coli ACV 1003 (recA:: lacZ) was used to measure low concentrations of DNA-damaging chemicals, which produce $\beta$-galactosidase via an SOS regulon system. Very low $\beta$-galactosidase activities of less than 0.01 unit/ml, $\beta$-galactosidase produced through an SOS response corresponding to the 10 ng/ml (ppb) of DNA damaging chemicals in the environment, can be rapidly determined by using an alternative interferometric biosensor with optically flat thin films of porous silicon rather than by the conventional time-consuming Miller's enzyme assay as well as the ELISA method. fu order to enhance the sensitivity in the interferometry, it needs to obtain more uniform distribution and higher biolinking efficiency, whereas interferometric sensing is rapid, cheap, and advantageous in high throughput by using a multiple-well-type chip. In this study, pore size adjusted to 60 nm for the target enzyme $\beta$-galactosidase to be bound on both walls of a Si pore and a calyx crown derivative was apllied as a more efficient biolinker. Furthermore, anti-$\beta$-galactosidase was previously functionalized with the biolinker for the target $\beta$-galactosidase to be specifically bound. When anti-$\beta$-galactosidase was bound to the calyx-crown derivative-linked surface, the effective optical thickness was found to be three times as high as that obtained without using anti-$\beta$-galactosidase. The resolution obtained was very similar to that afforded by the time-consuming ELISA method; however, the reproducibility was still unsatisfactory, below 1 unit $\beta$-galactosidase/ml, owing to the microscopic non-uniform distribution of the pores in the etched silicon surface.

Expression of $\beta$-Galactosidase Gene Microinjected into Xenopus Egg During Early Development (초기발생 동안 양서류 난에 미세주입된 $\beta$-galactosidase 유전자의 발현)

  • 차병직;정해문
    • The Korean Journal of Zoology
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    • v.33 no.3
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    • pp.365-372
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    • 1990
  • For the effort to produce transgenic amphibians, a plasmid DNA sequence (cytoplasmic actin promoter-linked bacterial $\beta$-galactosidase gene) was microinjected into fertilized Xenopus eggs. It appeared that the injection of 20 nl solution containing 1-2 ng of DNA was not toxic, but over 4 ng was toxic to embryonic development. The translational product of $\beta$-gal gene ($\beta$-galactosidase) had enzyme activity in all three germ layers of the embryo. Expression of the injected $\beta$-gal genes was first detected at mid-gastrula stage, and the activity persisted up to stage 43 (feeding tadpole) with decreased level of retention. However, the level of the expression was various among the injected individuals as well as each experiment. That is, $\beta$-galactosidase activities did not appear in all cells, instead a localized distribution pattern. Although other possibilities could not be omitted, this mosaic distribution of gene expression seemed to arise from unequal partition of the injected DNA into each blastomere during early cleavage.

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Molecular Characterization and Tissue Distribution of Estrogen Receptor Genes in Domestic Yak

  • Fu, Mei;Xiong, Xian-Rong;Lan, Dao-Liang;Li, Jian
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.12
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    • pp.1684-1690
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    • 2014
  • Estrogen and its receptors are essential hormones for normal reproductive function in males and females during developmental stage. To better understand the effect of estrogen receptor (ER) gene in yak (Bos grunniens), reverse transcription-polymerase chain reaction (PCR) was carried out to clone $ER{\alpha}$ and $ER{\beta}$ genes. Bioinformatics methods were used to analyze the evolutionary relationship between yaks and other species, and real-time PCR was performed to identify the mRNA expression of $ER{\alpha}$ and $ER{\beta}$. Sequence analysis showed that the ER open reading frames (ORFs) encoded 596 and 527 amino acid proteins. The yak $ER{\alpha}$ and $ER{\beta}$ shared 45.3% to 99.5% and 53.9% to 99.1% protein sequence identities with other species homologs, respectively. Real-time PCR analysis revealed that $ER{\alpha}$ and $ER{\beta}$ were expressed in a variety of tissues, but the expression level of $ER{\alpha}$ was higher than that of $ER{\beta}$ in all tissues, except testis. The mRNA expression of $ER{\alpha}$ was highest in the mammary gland, followed by uterus, oviduct, and ovary, and lowest in the liver, kidney, lung, testis, spleen, and heart. The $ER{\beta}$ mRNA level was highest in the ovary; intermediary in the uterus and oviduct; and lowest in the heart, liver, spleen, lung, kidney, mammary gland, and testis. The identification and tissue distribution of ER genes in yaks provides a foundation for the further study on their biological functions.

Mixtures of Beta Processes Priors for Right Censored Survival Data

  • Kim, Yongdai
    • Journal of the Korean Statistical Society
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    • v.30 no.1
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    • pp.127-138
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    • 2001
  • In order to combine parametric and nonparametric approaches together for survival analysis with censored observations, a new class of priors called mixtures of the beta processes is introduced. It is shown that mixtures of beta processes priors generalized the well known priors - mixtures of Dirichlet processes, and they are conjugate with right censored observations. Formulas for computing the posterior distribution are derived. Finally, a real data set is analyzed for illustrational purpose.

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Personalized EigenTrust with the Beta Distribution

  • Choi, Dae-Seon;Jin, Seung-Hun;Lee, Youn-Ho;Park, Yong-Su
    • ETRI Journal
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    • v.32 no.2
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    • pp.348-350
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    • 2010
  • This letter presents an enhancement of EigenTrust. Using the beta distribution, local trust values can be more correctly evaluated. Simulation shows that the proposed scheme calculates the local trust more correctly by up to 8%. For personalization, the proposed scheme provides cumulative transitive values from the local trust to the global trust with mathematically guaranteed convergence.

Sequential Confidence Set of the Mean Vector of a Multivariate Distribution

  • Kim, Sung Lai
    • Journal of the Chungcheong Mathematical Society
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    • v.5 no.1
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    • pp.87-97
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    • 1992
  • Sequential procedure with ${\beta}$-protection for the mean vector ${\mu}(\theta)$ of a p(> 1)-variate multivariate distribution $P_{\theta}$, ${\theta}{\in}{\Theta}$, with covariance matrix ${\sum}(\theta)$ is considered when the only nuisance parameters is ${\sum}(\theta)$. We obtain a confidence set for ${\mu}(\theta)$ with coverage probability condition and ${\beta}$-protection at ${\mu}-{\delta}(\mu)$ for some imprecision function ${\delta}:\mathbb{R}^p{\rightarrow}\mathbb{R}^p$.

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A Comparison of NLSY and CPS Data

  • Jo, Yoon-Ae
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.3
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    • pp.851-859
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    • 2006
  • The family income distributions of NLSY97 and CPS youth data are compared by using the generalized beta distribution of the second kind. The null hypothesis that the two data sets represent the same underlying population is rejected. The ML estimation suggests that NLSY97 data are oversampled in an income group of $11,308 or less, by about 15.7% compared to CPS data.

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On the STSP Normal Distribution

  • Choi, Jeen-Kap
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.2
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    • pp.451-456
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    • 2005
  • We introduce the standard two-sided power normal distribution and consider the relation between the probability in standard two-sided power distribution and the probability in standard two-sided power normal distribution and obtain the even moment of the special two-sided power normal distribution including the cases considered by Gupta and Nadarajah(2004)

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Performance improvement of high $\beta$ and low saturation voltage power transistor through new process (공정개선을 통한 고전류이득 저포화전압 전력 트랜지서터의 성능향상)

  • 김준식;이재곤;최시영
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.8
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    • pp.8-14
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    • 1998
  • A new process is developed to improve the electrical characteristics of high .beta. and low saturation voltage power transistor for lamp solenoid driver application. To prevent punch-through breakdown, appropriate combination of base doping and base width is necessary in the range of operating voltage of the circuit. The optimum values of base doping and sheet resistance are $Q_{D}$= $1.5{\times}10^{14}$atoms/$\textrm{cm}^2$ and $R_{s}$= 350 $\Omega/\square$ base wodtj $W_{B}$= $2.5{\mu}m$respectively. Under this condition it is possible to control $\beta$ of the transistor to 1500, maintaining $VB_{CBO}$ =200V. To reduce scattered distribution of .beta. of the devices on the wafer, it is necessary to improve emittter predeposition process. As a result, scattered distribution of .beta. of the devices on the wafer was reduced to 1/6 by using the new process. To improve collector to emitter forward voltage drop, $V_{ECF}$ of damper diode, an additional silicon etching process is used, which resulted in improving the value of $V_{eCF}$ from 2.8 V to 1.8V. With the suggested process superior device performance and higher yield are achieved.

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