• 제목/요약/키워드: Beta processes

검색결과 357건 처리시간 0.026초

Weak Convergence for Nonparametric Bayes Estimators Based on Beta Processes in the Random Censorship Model

  • Hong, Jee-Chang
    • Communications for Statistical Applications and Methods
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    • 제12권3호
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    • pp.545-556
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    • 2005
  • Hjort(1990) obtained the nonparametric Bayes estimator $\^{F}_{c,a}$ of $F_0$ with respect to beta processes in the random censorship model. Let $X_1,{\cdots},X_n$ be i.i.d. $F_0$ and let $C_1,{\cdot},\;C_n$ be i.i.d. G. Assume that $F_0$ and G are continuous. This paper shows that {$\^{F}_{c,a}$(u){\|}0 < u < T} converges weakly to a Gaussian process whenever T < $\infty$ and $\~{F}_0({\tau})\;<\;1$.

Synthesis and Mass Spectrometry of Deueteriu Labeled Tranylcypromine Hydrochloride

  • Kang, Gun-Il;Hong, Suk-Gil
    • Archives of Pharmacal Research
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    • 제8권2호
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    • pp.77-84
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    • 1985
  • [$^{2}$H$_{2}$] Tranylcypromine hydrochloride (trans-3, 3-dideuterio-2-phenylcyclopropylamine HCL) was synthesized for application to the metabolic studies. Mass fragmentation processes for the tranylcypromine and its two synthetic intermediates .gamma-phenyl-.gamma.-butyrolactone and trans-2-phenylcyclopropanecarboxylic acid were described based upon comparisons between labeled and unlabeled compounds.

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General Laws of the Iterated Logarithm for Levy Processes

  • Wee, In-Suk;Kim, Yun-Kyong
    • Journal of the Korean Statistical Society
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    • 제17권1호
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    • pp.30-45
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    • 1988
  • Let ${X(t) : 0 \leq t < \infty}$ be a real-valued process with stationary independent increments. In this paper, we obtain necesary and sufficint condition for there to exist a positive, nondecreasing function $\beta(t)$ so that $0 < lim sup $\mid$X(t)$\mid$/\beta(t) < \infty$ a.s. both as t tends to zero and infinity. When no such $\beta(t)$ exists we give a simple integral test for whether $lim sup $\mid$X(t)$\mid$/\beta(t)$ is zero or infinity for a given $\beta(t)$.

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Neuroprotective effects of gossypin on beta-amyloid- and oxidative stress-induced toxicity in primary cultured rat cortical cells

  • Yoon, In-Jae;Lee, Kwang-Heun;Cho, Jung-Sook
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.142.1-142.1
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    • 2003
  • Excessive accumulation of beta-amyloid (A$\beta$) peptides is one of the leading hypotheses to explain neurodegenerative processes in Alzheimer's disease (AD). It has been suggested that $A\beta$ toxicity is associated with increases in reactive oxygen species. whose overproduction may in turn initiate neurotoxic events. (omitted)

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Characterization of Microstructure and Mechanical Properties of Mg-8Li-3Al-1Y Alloy Subjected to Different Rolling Processes

  • Zhou, Xiao;Liu, Qiang;Liu, Ruirui;Zhou, Haitao
    • Metals and materials international
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    • 제24권6호
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    • pp.1359-1368
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    • 2018
  • The mechanical properties and microstructure evolution of Mg-8Li-3Al-1Y alloy undergoing different rolling processes were systematically investigated. X-ray diffraction, optical microscope, scanning electron microscopy, transmission electron microscopy as well as electron backscattered diffraction were used for tracking the microstructure evolution. Tensile testing was employed to characterize the mechanical properties. After hot rolling, the $MgLi_2Al$ precipitated in ${\beta}-Li$ matrix due to the transformation reaction: ${\beta}-Li{\rightarrow}{\beta}-Li+MgLi_2Al+{\alpha}-Mg$. As for the alloy subjected to annealed hot rolling, ${\beta}-Li$ phase was clearly recrystallized while recrystallization rarely occurred in ${\alpha}-Mg$ phase. With regard to the microstructure undergoing cold rolling, plenty of dislocations and dislocation walls were easily observed. In addition, the microstructure of alloys subjected to annealed cold rolling revealed the formation of new fresh ${\alpha}-Mg$ grains in ${\beta}-Li$ phase due to the precipitation reaction. The mechanical properties and fracture modes of Mg-8Li-3Al-1Y alloys can be effectively tuned by different rolling processes.

프로세스의 독립성, 데이터 가중치 체계, 부분군 형성과 관리도 용도에 따른 합격판정 관리도의 설계 (Design of Acceptance Control Charts According to the Process Independence, Data Weighting Scheme, Subgrouping, and Use of Charts)

  • 최성운
    • 대한안전경영과학회지
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    • 제12권3호
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    • pp.257-262
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    • 2010
  • The study investigates the various Acceptance Control Charts (ACCs) based on the factors that include process independence, data weighting scheme, subgrouping, and use of control charts. USL - LSL > $6{\sigma}$ that used in the good condition processes in the ACCs are designed by considering user's perspective, producer's perspective and both perspectives. ACCs developed from the research is efficiently applied by using the simple control limit unified with APL (Acceptable Process Level), RLP (Rejectable Process Level), Type I Error $\alpha$, and Type II Error $\beta$. Sampling interval of subgroup examines i.i.d. (Identically and Independent Distributed) or auto-correlated processes. Three types of weight schemes according to the reliability of data include Shewhart, Moving Average(MA) and Exponentially Weighted Moving Average (EWMA) which are considered when designing ACCs. Two types of control charts by the purpose of improvement are also presented. Overall, $\alpha$, $\beta$ and APL for nonconforming proportion and RPL of claim proportion can be designed by practioners who emphasize productivity and claim defense cost.

Mechanism and Products During the Homolytic Addition of CCl$_4$ and Cl$_3$CBr to $\beta$-Halostyrenes

  • Kim Sung-Soo
    • Bulletin of the Korean Chemical Society
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    • 제1권2호
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    • pp.45-49
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    • 1980
  • During the homolytic reactions of $CCl_4$ or $Cl_3CBr with ${\beta}-halo^1$-styrenes,$\beta$-haloradicals are key intermediates. They are to be stabilized via three pathways; $\beta$-cleavage, halogen transfer and telomerization. The three reaction paths are delicately controlled by the energetics of their formation and stabilization. When the formation of a $\beta$-haloradical is accompanied by considerable excess of energy from an exothermic reaction, $\beta$ -cleavage is often dominant over the halogen transfer. On the other hand, if the radical forms via a reversible reaction, two processes become competitive. $\beta$-Eliminated bromine atoms from ${\beta}$ -bromoradicals generate $Br_2$ via $Cl_3CBr + {\cdot}Br {\leftrightarrow} Br_2 + {CCl_3}{\cdot}{Br_2}$ may act as a better scavenger than Cl3CBr for the ${\beta}$-bromoradicals. Different reactivities of chlorine, bromine and trichloromethyl radicals towards olefinic pi-bond are clarified in terms of the beat content of the addition reactions.

On Asymptotic Properties of Bootstrap for Autoregressive Processes with Regularly Varying Tail Probabilities

  • Kang, Hee-Jeong
    • Journal of the Korean Statistical Society
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    • 제26권1호
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    • pp.31-46
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    • 1997
  • Let $X_{t}$ = .beta. $X_{{t-1}}$ + .epsilon.$_{t}$ be an autoregressive process where $\mid$.beta.$\mid$ < 1 and {.epsilon.$_{t}$} is independent and identically distriubted with regularly varying tail probabilities. This process is called the asymptotically stationary first-order autoregressive process (AR(1)) with infinite variance. In this paper, we obtain a host of weak convergences of some point processes based on bootstrapping of { $X_{t}$}. These kinds of results can be generalized under the infinite variance assumption to ensure the asymptotic validity of the bootstrap method for various functionals of { $X_{t}$} such as partial sums, sample covariance and sample correlation functions, etc.ions, etc.

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STATIONARY $\beta-MIXING$ FOR SUBDIAGONAL BILINEAR TIME SERIES

  • Lee Oe-Sook
    • Journal of the Korean Statistical Society
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    • 제35권1호
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    • pp.79-90
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    • 2006
  • We consider the subdiagonal bilinear model and ARMA model with subdiagonal bilinear errors. Sufficient conditions for geometric ergodicity of associated Markov chains are derived by using results on generalized random coefficient autoregressive models and then strict stationarity and ,a-mixing property with exponential decay rates for given processes are obtained.

Random Upper Functions for Levy Processes

  • Joo, Sang-Yeol
    • Journal of the Korean Statistical Society
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    • 제22권1호
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    • pp.93-111
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    • 1993
  • Let ${X(t) : t \geq 0}$ be a real-valued stochastics process with stationary independent increments. In this paper, under the condition of stochastic compactness, we obtain appropriate function $\alpha(t)$ and random function $\beta(t)$ such that for some positive finite constant C, lim sup${X(t) - \alpha(t)}/\beta(t) = C$ a.s. both as t tends to zero and infinity.

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