• Title/Summary/Keyword: Alpha value

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On Numerical Computation of Pickands Constants

  • Choi, Hyemi
    • Communications for Statistical Applications and Methods
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    • v.22 no.3
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    • pp.277-283
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    • 2015
  • Pickands constant $H_{\alpha}$ appears in the classical result about tail probabilities of the extremes of Gaussian processes and there exist several different representations of Pickands constant. However, the exact value of $H_{\alpha}$ is unknown except for two special Gaussian processes. Significant effort has been made to find numerical approximations of $H_{\alpha}$. In this paper, we attempt to compute numerically $H_{\alpha}$ based on its representation derived by $H{\ddot{u}}sler$ (1999) and Albin and Choi (2010). Our estimates are compared with the often quoted conjecture $H_{\alpha}=1/{\Gamma}(1/{\alpha})$ for 0 < ${\alpha}$ ${\leq}$ 2. This conjecture does not seem compatible with our simulation result for 1 < ${\alpha}$ < 2, which is also recently observed by Dieker and Yakir (2014) who devised a reliable algorithm to estimate these constants along with a detailed error analysis.

The Minimum Dwell Time Algorithm for the Poisson Distribution and the Poisson-power Function Distribution

  • Kim, Joo-Hwan
    • Communications for Statistical Applications and Methods
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    • v.4 no.1
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    • pp.229-241
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    • 1997
  • We consider discrimination curve and minimum dwell time for Poisson distribution and Poisson-power function distribution. Let the random variable X has Poisson distribution with mean .lambda.. For the hypothesis testing H$\_$0/:.lambda. = t vs. H$\_$1/:.lambda. = d (d$\_$0/ if X.leq.c. Since a critical value c can not be determined to satisfy both types of errors .alpha. and .beta., we considered discrimination curve that gives the maximum d such that it can be discriminated from t for a given .alpha. and .beta.. We also considered an algorithm to compute the minimum dwell time which is needed to discriminate at the given .alpha. and .beta. for the Poisson counts and proved its convergence property. For the Poisson-power function distribution, we reject H$\_$0/ if X.leq..'{c}.. Since a critical value .'{c}. can not be determined to satisfy both .alpha. and .beta., similar to the Poisson case we considered discrimination curve and computation algorithm to find the minimum dwell time for the Poisson-power function distribution. We prosent this algorithm and an example of computation. It is found that the minimum dwell time algorithm fails for the Poisson-power function distribution if the aiming error variance .sigma.$\^$2/$\_$2/ is too large relative to the variance .sigma.$\^$2/$\_$1/ of the Gaussian distribution of intensity. In other words, if .ell. is too small, we can not find the minimum dwell time for a given .alpha. and .beta..

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Image and Altitude on the Alpha-Numeric Brand Name of Fashion Products (패션제품의 숫자 결합 상표명에 대한 이미지와 태도에 관한 연구)

  • Park Hye-Won;Ryou Eun-Jeong
    • The Research Journal of the Costume Culture
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    • v.13 no.3 s.56
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    • pp.494-502
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    • 2005
  • The purposes of this study were to investigate the images on the alpha numeric brand name of fashion products, to identify the influences of clothing pursuit benefit on the brand name image and to determine the significant images on the attitude and purchasing intention. The data were collected via a self-administered questionnaire from 270 male and female students of undergraduate school in Kyongnam province during the March, 2004. Using SPSS 12.0 package, Cronbach's a, frequency analysis, factor analysis, and multiple regression analysis were performed. The results could be summarized as follows: First, the image dimensions of alpha-numeric brand name were composed of natural, new, active, urban, impactive and interesting image. Clothing pursuit benefits were composed of the brand value, attractiveness, fashion, individuality and economic value pursuit, Second, Clothing pursuit benefits had an significant effect on the image preference of alpha-numeric brand name. Especially, individuality pursuit and attractiveness pursuit have influenced on the natural, new, active, urban images. Third, the new, active, impactive, natural images had significant effects on the attitude, purchasing intention and conformity of products.

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Piezoelectric Characteristics and Temperature Stability of Resonant Frequency of PbTiO3 System Ceramics for High Frequency Resonator using Srd Overtone Thickness Vibration Mode

  • Yoo, Juhyun ;Min, Sukkyu ;Hwang, Sangmo ;Park, Changyub;Yoon, Hyunsang
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.4
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    • pp.338-343
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    • 2002
  • In this study, $Pb_{0.88}(La_{\alpha}Nd_{1-\alpha})_{0.08}(Mn_{1/3}Sb_{2/3})_{0.02}Ti_{0.98}O_3$ system ceramics with La molar ratio $\alpha$ variation were manufactured for 24 MHz class resonator application. Electromechanical coupling factor, mechanical quality factor and dynamic range of $3^{rd}$ overtone thickness vibration mode were measured as the variations of La and Nd molar ratio. Mechanical quality factor and dynamic range at $\alpha$ = 0.6 composition ceramics showed the highest value of 2691 and 52.37 dB, respectively. The temperature coefficient of resonant frequency measured from $-20^{\circ} to 80^{\circ}$ showed an excellent value of $5ppm/^{\circ}C$ at $\alpha$=1 composition ceramics.

Infrared Spectra and Electrical Conductivity of The Solid Solutions X MgO + (1-X) ${\alpha}-Nb_2$ $O_5$; 0.01{\leq}X{\leq}0.09

  • Park Zin;Park, Jong Sik;Lee Dong Hoon;Jun Jong Ho;Yo Chul Hyun;Kim Keu Hong
    • Bulletin of the Korean Chemical Society
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    • v.13 no.2
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    • pp.127-131
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    • 1992
  • Changes in network structures of ${\alpha}-Nb_2O_5$ in the X MgO+(1-X) ${\alpha}-Nb_2O_5$ solid solutions occurring as the MgO doping level (X) was varied were investigated by means of infrared spectroscopy and X-ray analysis. X-ray diffraction revealed that all the synthesized specimens have the monoclinic structure. The FT-IR spectroscopy showed that the system investigated forms the solid solutions in which $Mg^{2+}$ ions occupy the octahedral sites in parent crystal lattice. Electrical conductivities were measured as a function of temperature from 600 to $1050{\circ}$ and $P_{O2}$ form $1{\times}10^{-5}$ to $2{\times}10^{-1}$ atm. The defect structure and conduction mechanism were deduced from the results. The $1}n$ value in ${\alpha}{\propto}{P_{O2}^{1}n}}$ is found to be -1/4 with single possible defect model. From the activation energy ($E{\alpha}$ = 1.67-1.73 eV) and the1/n value, electronic conduction mechanism is suggested with a doubly charged oxygen vacancy.

Studies on antioxidative action of Garlic components isolated from garlic - Part 1. Effects of garlic components on electron donating ability and inhibitory effect of lipoperoxide formation (마늘성분의 산화방지작용에 관한 연구 - 제1보 전자공여능 및 과산화지질생성억제효과에 미치는 영향)

  • 전희정
    • Journal of the Korean Home Economics Association
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    • v.24 no.1
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    • pp.43-51
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    • 1986
  • In order to study antioxidative acton of garlic, alliin, scordinin, garlic oil, ethanol fraction and non-kaolin fraction which have been discovered from garlic until now were extracted and isolated, and each fraction was utilized as the experimental materials. Antioxidative action of each fraction was compared through the in vitro and in vivo experiments. Electron donatingability on $\alpha$, $\alpha$-diphenyl-$\beta$picrylhydra-$\chi$yl, the inhibitory effect of lipoperoxide formation by TBA and peroxide value were measured and analyzed. RESULTS : 1. When observed antioxidative ability by EDA value, ethanol fraction of garlic components showed the strongest reaction as 15.25. 2. In vitro experiment with TBA value, garlic oil, alliin and ethanol fracton showed distinctive effect on inhibitory effect of lipoperoxide formation. 3. Comparing with the inhibitory effect of lipoperoxide formation with TBA value in vivo, the ethanol fraction was the most effective in the blood or liver by intraperitoneal administration, whereas the ethanol fraction in the blood and non-kaolin fraction in the liver was most effective each other by orally administration. 4. In vitro experiment with peroxide value, garlic oil was distinctive effect on the inhivitory effect of lipoperoxide formation, which was a similar to the trend of TBA value in vitro. 5. Examining the induction time for the first period of lipoperoxide formation in vitro, garlix oil, ethanol fraction and alliin were effective, which was a similar to the trend of TBA value and peroxide value in vitro.

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Immunohistochemical Expression and Prognostic Value of VEGF, HIF-$1{\alpha}$, EGFR in Non-Small Cell Lung Cancer (비소세포 폐암에서 VEGF, HIF-$1{\alpha}$, EGFR의 면역조직화학적 발현과 예후 인자로서의 역할)

  • Kim, Myung-Sook;Park, Sung-Hak
    • Tuberculosis and Respiratory Diseases
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    • v.68 no.1
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    • pp.22-28
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    • 2010
  • Background: Vascular endothelial growth factor (VEGF) is a potent mediator of angiogenesis. VEGF production is regulated by HIF-$1{\alpha}$ and EGFR. This study examined the relationship between the clinicopathological factors and VEGF, HIF-$1{\alpha}$ and EGFR protein overexpression, and evaluated their prognostic value in patients with a surgically resected non-small cell lung cancer (NSCLC). Methods: Patients who underwent a surgical resection at Kangnam St. Mary's hospital were reviewed retrospectively. The core biopsy samples from 54 patients with NSCLC were assembled on a tissue microarray (TMA), and immunohistochemical staining for the VEGF, HIF-$1{\alpha}$ and EGFR proteins was performed. The overexpression of these proteins was evaluated in relation to age, gender, histology and staging by univariate analysis. The clinicopathological prognostic factors were analyzed. Results: Multivariate analysis performed by Cox regression (odds ratio 2.8, 95% CI 1.0~8.2, p=0.046) revealed HIF-$1{\alpha}$ overexpression to be an unfavorable factor. There was no correlation between the overexpression of these proteins and the clinicopathological factors. VEGF showed a positive relationship with EGFR, but there was no statistical significance [$p(x^2)=0.06$]. Conclusion: HIF-$1{\alpha}$ overexpression predicts shorter survival in patients with a surgically resected NSCLC. Therefore, HIF-$1{\alpha}$ may be a poor prognostic factor in NSCLC.

MULTI-POINT BOUNDARY VALUE PROBLEMS FOR ONE-DIMENSIONAL p-LAPLACIAN AT RESONANCE

  • Wang Youyu;Zhang Guosheng;Ge Weigao
    • Journal of applied mathematics & informatics
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    • v.22 no.1_2
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    • pp.361-372
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    • 2006
  • In this paper, we consider the multi-point boundary value problems for one-dimensional p-Laplacian at resonance: $({\phi}_p(x'(t)))'=f(t,x(t),x'(t))$, subject to the boundary value conditions: ${\phi}_p(x'(0))={\sum}^{n-2}_{i=1}{\alpha}_i{\phi}_p(x'({\epsilon}i)),\;{\phi}_p(x'(1))={\sum}^{m-2}_{i=1}{\beta}_j{\phi}_p(x'({\eta}_j))$ where ${\phi}_p(s)=/s/^{p-2}s,p>1,\;{\alpha}_i(1,{\le}i{\le}n-2){\in}R,{\beta}_j(1{\le}j{\le}m-2){\in}R,0<{\epsilon}_1<{\epsilon}_2<...<{\epsilon}_{n-2}1,\;0<{\eta}1<{\eta}2<...<{\eta}_{m-2}<1$, By applying the extension of Mawhin's continuation theorem, we prove the existence of at least one solution. Our result is new.

Comparison of evaluation methods for measuring pressure of compressionwear (컴프레션웨어의 압박감 측정 방법 비교 연구)

  • Park, Jee Hye;Chun, Jongsuk
    • The Research Journal of the Costume Culture
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    • v.21 no.4
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    • pp.535-545
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    • 2013
  • The aim of this study was comparing measuring tools for detecting physical comfortness with variation of garment pressure. The measuring tools for detecting physical comfortness were EEG and survey questionnaire. Two low-pressure compressionwears and a commercial compressionwear (girdle) were tested. Results showed that the questionnaire survey well detected suffocation or motion comfortness. But it did not discrete the appropriate tightness of the compressionwears. The results of EEG analysis show that the absolute power of ${\alpha}$-wave value was elevated with the low-pressure compressionwears. It also showed lower stress value. The high-pressure compressionwear presented decreased absolute power of ${\alpha}$-wave value. It showed higher stress value. These results implicate that EEG can appropriatly indicate the change of physical comfortness of compressionwear. The appropriate tightness of compressionwear can be measured with EEG analysis rather than survey questionnaire.

EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS FOR SINGULAR THREE-POINT BOUNDARY VALUE PROBLEMS

  • Miao, Chunmei;Ge, Weigao
    • Journal of applied mathematics & informatics
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    • v.27 no.3_4
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    • pp.895-902
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    • 2009
  • In this paper, the singular three-point boundary value problem $$\{{{u"(t)\;+\;f(t,\;u)\;=\;0,\;t\;{\in}\;(0,\;1),}\atop{u(0)\;=\;0,\;u(1)\;=\;{\alpha}u(\eta),}}\$$ is studied, where 0 < $\eta$ < 1, $\alpha$ > 0, f(t,u) may be singular at u = 0. By mixed monotone method, the existence and uniqueness are established for the above singular three-point boundary value problems. The theorems obtained are very general and complement previous know results.

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