• Title/Summary/Keyword: t Distribution

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The effect of non-uniform current distribution on transport current loss in stacked high-Tc superconductor tapes

  • Choi, Se-Yong;Nah, Wan-Soo;Joo, Jin-Ho;Ryu, Kyung-Woo;Lee, Byoung-Seob;Yoon, Jang-Hee;Ok, Jung-Woo;Park, Jin-Yong;Won, Mi-Sook
    • Progress in Superconductivity and Cryogenics
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    • v.14 no.2
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    • pp.16-19
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    • 2012
  • The influence of current distribution on the transport current loss in vertically stacked high-$T_c$ superconductor (HTS) tapes was evaluated. AC loss was analyzed as a function of current distribution by introducing a current distribution parameter through a numerical method (finite element analysis). AC loss under non-uniform current distribution is always higher than that for a uniformly distributed transport current in a conductor. Although the effect of non-uniformity is relatively insignificant in low transport current, AC loss increases substantially in high transport current regions as non-uniformity is enlarged. The results verify that non-uniform current distribution causes extra loss by examining the cross-sectional view of current densities in stacked conductor.

Parametric survival model based on the Lévy distribution

  • Valencia-Orozco, Andrea;Tovar-Cuevas, Jose R.
    • Communications for Statistical Applications and Methods
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    • v.26 no.5
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    • pp.445-461
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    • 2019
  • It is possible that data are not always fitted with sufficient precision by the existing distributions; therefore this article presents a methodology that enables the use of families of asymmetric distributions as alternative probabilistic models for survival analysis, with censorship on the right, different from those usually studied (the Exponential, Gamma, Weibull, and Lognormal distributions). We use a more flexible parametric model in terms of density behavior, assuming that data can be fit by a distribution of stable distribution families considered unconventional in the analyses of survival data that are appropriate when extreme values occur, with small probabilities that should not be ignored. In the methodology, the determination of the analytical expression of the risk function h(t) of the $L{\acute{e}}vy$ distribution is included, as it is not usually reported in the literature. A simulation was conducted to evaluate the performance of the candidate distribution when modeling survival times, including the estimation of parameters via the maximum likelihood method, survival function ${\hat{S}}$(t) and Kaplan-Meier estimator. The obtained estimates did not exhibit significant changes for different sample sizes and censorship fractions in the sample. To illustrate the usefulness of the proposed methodology, an application with real data, regarding the survival times of patients with colon cancer, was considered.

CO-CLUSTER HOMOTOPY QUEUING MODEL IN NONLINEAR ALGEBRAIC TOPOLOGICAL STRUCTURE FOR IMPROVING POISON DISTRIBUTION NETWORK COMMUNICATION

  • V. RAJESWARI;T. NITHIYA
    • Journal of applied mathematics & informatics
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    • v.41 no.4
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    • pp.861-868
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    • 2023
  • Nonlinear network creates complex homotopy structural communication in wireless network medium because of complex distribution approach. Due to this multicast topological connection structure, the queuing probability was non regular principles to create routing structures. To resolve this problem, we propose a Co-cluster homotopy queuing model (Co-CHQT) for Nonlinear Algebraic Topological Structure (NLTS-) for improving poison distribution network communication. Initially this collects the routing propagation based on Nonlinear Distance Theory (NLDT) to estimate the nearest neighbor network nodes undernon linear at x(a,b)→ax2+bx2 = c. Then Quillen Network Decomposition Theorem (QNDT) was applied to sustain the non-regular routing propagation to create cluster path. Each cluster be form with co variance structure based on Two unicast 2(n+1)-Z2(n+1)-Z network. Based on the poison distribution theory X(a,b) ≠ µ(C), at number of distribution routing strategies weights are estimated based on node response rate. Deriving shorte;'l/st path from behavioral of the node response, Hilbert -Krylov subspace clustering estimates the Cluster Head (CH) to the routing head. This solves the approximation routing strategy from the nonlinear communication depending on Max- equivalence theory (Max-T). This proposed system improves communication to construction topological cluster based on optimized level to produce better performance in distance theory, throughput latency in non-variation delay tolerant.

Yonsei Evolutionary Population Synthesis (YEPS) Model -III. Spectrophotometric Evolutions of Simple Stellar Population Models based on Empirical Spectra

  • Chung, Chul;Yoon, Suk-Jin;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.38.1-38.1
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    • 2013
  • We present the Yonsei evolutionary population synthesis (YEPS) models based on the high-resolution empirical spectral energy distributions (SEDs). We have adopted the MILES library in the optical wavelength, and our new models based on the MILES library show good agreements with our previous models presented in the YEPS I. The effect of hot horizontal-branch (HB) stars on the integrated properties of simple stellar populations (SSPs) is again confirmed by our models based on empirical SEDs. In addition, we have extended our empirical models to the near-IR wavelength and predicted the strengths of the calcium II triplet (CaT) and the Paschen triplet (PaT) based on the INDO-US and the Cenarro library. We find that the effect of HB stars and the age of SSPs on the CaT is almost negligible. On the other hands, the PaT models are very sensitive to the existence of hot stars, e.g., HB stars and young turn-off stars, and show very similar results with Balmer lines. Interestingly, the CaT distribution of GCs in NGC 1407, which is at odds with the optical (B-I) color distribution, can be explained by the unique feature of the CaT-[Fe/H] relations that show almost the same equivalent widths in the metal-rich regime. We will also discuss the impact of the second-generation populations on the strength of the CaT.

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Tensile Behavior Analyses of Tubular Column to H-Beam Connections with T-Stiffeners (외부 T 스티프너를 이용한 각형강관기둥-H 형강보 접합부의 인장거동 해석)

  • Shin, Kyung Jae;Kwon, Young Ran
    • Journal of Korean Society of Steel Construction
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    • v.14 no.1
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    • pp.69-78
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    • 2002
  • This paper describes the analysis results for tensile behavior of tubular column to H-beam connection with T stiffeners. Using the elasto-plastic finite element method, analysis results are compare with experimental results. Parametric analyses with different size of T-stiffener have conducted to understand the stress distribution at the connections. Stress concentration in elastic region and PEEQ distribution in plastic region are plotted for different shape. The results of analysis were applied to design equations and were checked for the applicability of design equations.

Physiological Responses of Quick Absorbing/Drying T-shirts Designed with Sweating and Skin Temperature Distribution (발한 및 피부온 분포를 적용한 흡한속건 T-Shirts의 착용생리반응)

  • Ha, Ji-Hyun;Kim, Hee-Eun
    • Fashion & Textile Research Journal
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    • v.13 no.4
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    • pp.635-643
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    • 2011
  • This study was investigated to evaluate the physiological responses on T-shirts manufactured with selected functional materials by body parts which were selectioned on the distribution of sweating and temperature change. Seven healthy men in twenties were participated in a climate chamber of $27{\pm}0.5^{\circ}C$ and $50{\pm}1%RHC$. Three kinds of T-shirts named 'D1', 'D2' and 'Poly' were used as experimental clothings. Four kinds of functional materials of quick absorbing/drying were used in all section in 'D1', but two kinds of functional materials used partially in 'D2'. 'Poly' T-shirts used only polyester. In an experimental schedule of 90 minutes, which were consisted of 'Rest', twice of 'Exercise' and twice of 'Recovery' periods, the subjects walked on a treadmill with 60% of $VO_2max$. As a physiological responses, the microclimate temperature, surface temperature(skin, clothing) and sweat rate were measured. Temperature regulation was kept well in 'D1' rather than other T-shirts. The quick absorbing/drying T-shirts showed its performance well as the exercise goes on the second half. With these results in mind, 'D1' will be more effective for long hours exercise such as climbing rather than short hours exercise.

A photoelastic study of the stress distribution on canine retraction by segmented TMA T-loop spring (Segmented TMA T-loop spring에 의한 견치 후방이동시의 응력분포에 관한 광탄성법적 분석)

  • Yoon, Young-Jooh;Kim, Kwang-Won;Yu, Pil-Sik
    • The korean journal of orthodontics
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    • v.31 no.2 s.85
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    • pp.199-207
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    • 2001
  • The segmented TMA T-loop spring, used for reciprocal space closure and described by Burstone, was used to achievebodily movement of canine. Photoelastic analysis is a technique for the transformation of internal stress into visible light patterns. The two-dimensional photoelastic stress analysis was performed, and stress distribution was recorded by photography. The purpose of this study was to visualize photoelastically the distribution of forces transmitted to the alveolus and surrounding structures using new segmented TMA T-loop spring for canine retraction. The results were as follows: 1. Decreased activation produced decreased stress of upper 1st. premolar extraction site and increased intrusive stress of upper 1st. molar, regardless of T-loop position. 2. At 5mm activation, More posterior positioning of T-loop Produced an increased stress in upper 1st. premolar extraction site. 3. At 3mm activation, More posterior positioning of T-loop produced an increased stress in upper 1st. premolar extraction site and mesial lower half of upper 1st. molar mesio-buccal root. 4. At 1mm activation, More anterior positioning of T-loop produced an increased stress in upper mesial and blew apex area of upper canine root. 5. 0.25 B/L ratio and 3mm activation produced bodily movement of canine. To summarize, desired tooth movement and anchorage requirement is possible by altering the activation and mesio-distal position of the T-loop spring.

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CENTRAL LIMT THEOREMS FOR MULTITYPE AGE-DEPENDENT BRANCHING PROCESSES

  • Kang, Hye-Jeong
    • Journal of the Korean Mathematical Society
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    • v.36 no.6
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    • pp.1115-1132
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    • 1999
  • We consider a supercritical multitype age dependent branching process. We define a stochastic process Zf(t) which is a functional of the empirical age distribution. When the limit of the expectation of this functional vanishes we4 find some sufficient conditions for the asymptotic normality of the mean of f with respect to the empirical age distribution at time t.

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Detection of Random Effects in a Random Effects Model of a One-way Layout Contingency Table

  • Kim, Byung-Soo
    • Journal of the Korean Statistical Society
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    • v.13 no.1
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    • pp.1-19
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    • 1984
  • A random effects model of a one-way layout contingency table is developed using a Dirichlet-multinomial distribution. A test statistic, say $T_k$, is suggested for detecting Dirichlet-multinomial departure from a multinomial distribution. It is shown that the $T_k$ test is asymptotically superior to the classical chi-square test based on the asymptotic relative efficiency. This superiority is further evidenced by a Monte Carlo simulation.

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