Browsing Mathematics, Statistics, and Physics by Title
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Estimating cumulative incidence functions when the life distributions are constrained
(Academic Press, 2010055)In competing risks studies, the KaplanMeier estimators of the distribution functions (DFs) of lifetimes and the corresponding estimators of cumulative incidence functions (CIFs) are used widely when no prior information ... 
Estimation of a starshaped distribution function
(Taylor & Francis LTD, 2017)A life distribution function (DF) F is said to be starshaped if F(x)/x is nondecreasing on its support. This generalises the model of a convex DF, even allowing for jumps. The nonparametric maximum likelihood estimation ... 
Estimation of distributions with the new better than used in expectation property
(Elsevier, 201305)A lifetime X with survival function S, mean residual life function (MRL) M, and finite mean μ is said to be new better than used in expectation (NBUE) if M(t)≤μ for all t≥0. We propose a new estimator for S, based on a ... 
Examples of discontinuity for the variational solution of the minimal surface equation with Dirichlet data on a domain with a nonconvex corner and locally negative mean curvature
(Wichita State University, 201312)The purpose of this thesis is to investigate the role of smoothness, specifically the smoothness of the boundary ∂Ω, in the behavior of the variational solution f on a domain Ω to the Dirichlet problem for the Minimal ... 
The existence of MorseSmale diffeomorphisms in the family of Hénon maps
(Wichita State University, 200905)We consider Hénon maps on ℝ² of the form fa,c(x,y)=(y,y2+c+ax) with real parameters (a, c). Due to the work of S. Hayes and C. Wolf [8], we provide a detailed investigation of the parameters 0 < a < 1 and c = 0. For each ... 
Experimental pairwise entanglement estimation for an Nqubit system: a machine learning approach for programming quantum hardware
(Springer, 20201103)Designing and implementing algorithms for medium and largescale quantum computers is not easy. In the previous work, we have suggested, and developed, the idea of using machine learning techniques to train a quantum ... 
Extending the piecewise exponential estimator of the survival function
(Wichita State University. Graduate School., 20080425)We propose a new way of extending the piecewise exponential estimator (PEXE) beyond the last observation, where the original PEXE and the KaplanMeier estimator (KME) of the true survival function (SF) are undefined. ... 
Fairest edge usage and minimum expected overlap for random spanning trees
(Elsevier, 202105)Random spanning trees of a graph $G$ are governed by a corresponding probability mass distribution (or "law"), $\mu$ defined on the set of all spanning trees of $G$ This paper addresses the problem of choosing $\mu$ in ... 
A fast local level set method for inverse gravimetry
(GlobalScience Press, 2011)We propose a fast local level set method for the inverse problem of gravimetry. The theoretical foundation for our approach is based on the following uniqueness result: if an open set D is starshaped or x(3)convex with ... 
First measurement of electron neutrino appearance in NOvA
(American Physical Society, 20160413)We report results from the first search for $\nu_\mu\to\nu_e$ transitions by the NOvA experiment. In an exposure equivalent to $2.74\times10^{20}$ protonsontarget in the upgraded NuMI beam at Fermilab, we observe 6 events ... 
First measurement of muonneutrino disappearance in NOvA
(American Physical Society, 20160325)This paper reports the first measurement using the NOvA detectors of $\nu_\mu$ disappearance in a $\nu_\mu$ beam. The analysis uses a 14 ktonequivalent exposure of $2.74 \times 10^{20}$ protonsontarget from the Fermilab ... 
FischerTropsch synthesis: Activity and selectivity of chiFe5C2 and circle minusFe3C carbides
(American Chemical Society, 20140810)Two different iron carbides, Hägg (χFe5C2) and cementite (ϴFe3C) for FischerTropsch synthesis (FTS) was investigated. Both iron carbides were oxidized to Fe3O4 during FTS. Hägg carbide (χFe5C2), initially exhibits ... 
FischerTropsch synthesis: Deactivation as a function of potassium promoter loading for precipitated iron catalyst
(Springer, 201410)The effect of potassium promoter loading (0, 0.5, 1.0 and 2.0 atomic ratio) on the performance of precipitated iron catalysts was investigated during FischerTropsch synthesis using a continuously stirred tank reactor. ... 
FischerTropsch synthesis: Effect of activation gas after varying Cu promoter loading over Kpromoted Febased catalyst
(© Springer, 201409)The effects of activation gas and copper promoter loading on the FischerTropsch synthesis performance of potassium promoted precipitated ironbased catalysts were investigated using a continuously stirred tank reactor. ... 
FischerTropsch synthesis: Effect of ammonia in syngas on the FischerTropsch synthesis performance of a precipitated iron catalyst
(Elsevier B.V., 201506)The effect of ammonia in syngas on the FischerTropsch synthesis (FTS) reaction over 100Fe/5.1Si/2.0Cu/3.0K catalyst was studied at 220270 degrees C and 1.3 MPa using a 1L slurry phase reactor. The ammonia added in syngas ... 
FischerTropsch synthesis: Effect of CO conversion on CH4 and oxygenate selectivities over precipitated FeK catalysts
(Elsevier, 20180625)The explanation for CH4 selectivity for iron based FischerTropsch catalysts in the low conversion region (Le., < 50%) remains elusive. In this contribution, the CO conversion effect was carefully examined over four K ... 
FischerTropsch synthesis: Effect of Cu, Mn and Zn addition on activity and product selectivity of cobalt ferrite
(Royal Society of Chemistry, 2016)The effect of Cu, Mn and Zn addition on cobalt ferrite was investigated for FischerTropsch synthesis (FTS). Oxalate coprecipitation followed by decomposition under inert conditions was used to obtain various metal ... 
FischerTropsch Synthesis: Effect of potassium on activity and selectivity for oxide and carbide Fe catalysts
(Springer US, 201311)The effect of potassium on oxides and carbides of iron for FischerTropsch synthesis (FTS) was investigated by pretreating Fe3O4 and Kpromoted Fe catalysts with different gases (H2/H2O and CO). A freshly activated sample ... 
FischerTropsch synthesis: Effects of hydrohalic acids in syngas on a precipitated iron catalyst
(American Chemical Society, 201505)The current investigation was undertaken to identify limits of hydrohalic acid (HX, X = F, Cl, Br) impurities in syngas and shed light on the mechanism of FIX poisoning of a 100 Fe/5.1 Si/2 Cu/3 K FTS catalyst under ... 
FischerTropsch synthesis: Morphology, phase transformation, and carbonlayer growth of ironbased catalysts
(John Wiley & Sons, Inc., 201407)The morphological, phase transformations and carbonlayer growth for unpromoted and Kpromoted iron catalysts were investigated over time during FischerTropsch synthesis. Catalysts were activated in CO for 24 h, which ...