• Journal of applied mathematics & informatics
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• 제40권5_6호
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• pp.925-931
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• 2022

In this article, we compare the reliability and the hazard function between a baseline distribution and the corresponding transmuted-G distribution. Some examples based on existing transmuted-G distributions in literature are used. Three tests of parameter significance are utilized to test the importance of a transmuted-G distribution over the baseline distribution, and real data is used in an application of the inference about the importance of transmuted-G distributions.

• Communications for Statistical Applications and Methods
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• 제26권3호
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• pp.239-259
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• 2019

The transmuted generalized extreme value (TGEV) distribution was first introduced by Aryal and Tsokos (Nonlinear Analysis: Theory, Methods & Applications, 71, 401-407, 2009) and applied by Nascimento et al. (Hacettepe Journal of Mathematics and Statistics, 45, 1847-1864, 2016). However, they did not give explicit expressions for all the moments, tail behaviour, quantiles, survival and risk functions and order statistics. The TGEV distribution is a more flexible model than the simple GEV distribution to model extreme or rare events because the right tail of the TGEV is heavier than the GEV. In addition the TGEV distribution can adjusted various forms of asymmetry. In this article, explicit expressions for these measures of the TGEV are obtained. The tail behavior and the survival and risk functions were determined for positive gamma, the moments for nonzero gamma and the moment generating function for zero gamma. The performance of the maximum likelihood estimators (MLEs) of the TGEV parameters were tested through a series of Monte Carlo simulation experiments. In addition, the model was used to fit three real data sets related to financial returns.

• 방사선산업학회지
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• 제9권3호
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• pp.111-117
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• 2015

In this paper, production of $^{166}Ho$ by double neutron capture from HANARO research reactor was evaluated. This production approach provides $^{166}Ho$ with high specific activity. $^{164}Dy$ is transmuted into $^{165g+m}Dy$ by (n,${\gamma}$) reaction, then $^{165g+m}Dy$ is transmuted into $^{166}Dy$ by (n,${\gamma}$) reaction. At the end of neutron irradiation, population of $^{166}Dy$ atoms reaches highest point. And $^{164}Dy$ exists as a mixture with $^{165m}Dy$, $^{165}Dy$, $^{166}Ho$ and $^{165}Ho$ at this point. To obtain $^{166}Ho$ with high specific activity, Ho isotopes from irradiated target is separated out. Then $^{166}Ho$ decayed from $^{166}Dy$ is eluted at radioactive equilibrium state. At each step, the number of relevant nuclide is calculated by the state equation. The neutron irradiation time for maximum $^{166}Dy$ is calculated for 283 hour. When 100 mg target of $Dy_2O_3$ (96.8% enriched $^{164}Dy$) is used, possible activity of $^{166}Ho$ is 3.54 Ci($1.31{\times}10^{11}Bq$). For separation efficiency of Dy/Ho is 99.99%, $^{166}Ho/Ho$ is 0.62.

• 한국산학기술학회논문지
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• 제12권12호
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• pp.5963-5973
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• 2011

현재 사용되고 있는 소일네일링 구조물에 관한 설계 및 해석법들은 실내모형실험이나 원형실험 또는 수치해석 결과를 바탕으로 주변지반과 보강네일 사이의 상호작용 메카니즘을 달리 적용함으로서 서로 다른 안전율을 제시하고 있다. 이러한 해석법들은 네일의 강성도나 지반조건 등이 가정된 바와 같이 잘 일치할 경우에는 합리적인 설계법이 될 수 있다. 하지만 이와 조건이 다른 경우 부적절한 결과를 가져올 가능성이 크다. 따라서, 본 연구에서는 원심모형시험기를 사용하여 소일네일링 구조물의 거동과 파괴메카니즘에 관한 매개변수적 실험을 실시하였다. 매개변수적 실험에서는 네일의 길이 및 설치각, 네일과 전면판의 강성도 등을 다양하게 변화시키면서 모형 벽체가 파괴될 때까지 중력수준을 증가시키는 자중실험을 실시하였다. 실험으로부터 얻어진 결과를 바탕으로 매개변수의 변화에 따른 영향, 파괴메카니즘 등을 비교분석하였다. 원심모형실험 결과와 현재 사용되고 있는 방법들과 비교 검토함으로서 기존 방법들에 대한 타당성을 검증하였다.