Browsing Mathematics, Statistics & Physics by Publication Date
Now showing items 21-40 of 666
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Is hypertension a predictor for heart failure? A cross cultural comparison over a 10-year period
( Elsevier B.V. , 2005 , Article)This was a retrospective cohort study to assess the effect of hypertension (HTN) among Qatari and Asian patients admitted to the Hamad General Hospital in Qatar with heart failure (HF) and to identify risk factors that ... -
Disability, depression and somatization in a low back pain population
( Blackwell Publishing Asia , 2006 , Article)Objective: The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods: This ... -
Large sample and bootstrap intervals for the gamma scale parameter based on grouped data
( Wayne State University , 2006 , Article)Interval estimation of the scale parameter of the gamma distribution using grouped data is considered in this article. Exact intervals do not exist and approximate intervals are needed Recently, Chen and Mi (2001) proposed ... -
Self-implantation of Cz-Si: Clustering and annealing of defects
( Elsevier , 2006 , Article)Observations of vacancy clusters formed in Czochralski (Cz) Si after high energy ion implantation are reported. Vacancy clusters were created by 2 MeV Si ion implantation of 1 × 10 15 ions/cm 2 and after annealing between ... -
Investigations of He <sup>+</sup> implantation and subsequent annealing effects in InP
( Elsevier , 2006 , Article)The influence of 70 keV He + ion implantation and subsequent annealing of Cz-indium phosphide (InP) samples has been investigated using a slow positron beam-based Doppler broadening spectrometer. Three samples with ion ... -
Applied surface Science: Preface
( Elsevier , 2006 , Other)not available -
The effect of gamma irradiation and shelf aging in air on the oxidation of ultra-high molecular weight polyethylene
( Elsevier , 2006 , Article)This study has investigated the effect of shelf aging, for up to one year in air, on the properties of gamma-irradiated ultra-high molecular weight polyethylene (UHMWPE). A variety of techniques were used to characterize ... -
Corrosion properties of duplex treated Ti-6Al-4V alloy in chloride media using electrochemical and positron annihilation spectroscopy techniques
( Elsevier B.V. , 2006 , Article)The corrosion properties of duplex-treated and nitrided Ti-6Al-4V have been investigated in 0.025, 0.25 and 2.5 M NaCl using electrochemical techniques, Positron Annihilation Spectroscopy (PAS), X-ray diffraction (XRD), ... -
TESTING SYMMETRY USING A TRIMMED LONGEST RUN STATISTIC
( Blackwell Publishing Asia Pty Ltd. , 2007 , Article)A distribution-free test is proposed for the symmetry of a continuous distribution about a specified median. The test is based on a longest run statistic on the upper portion of the sequence of ordered �centred� observations ... -
Gamma irradiation effects on polymethyl methacrylate
( WILEY-VCH Verlag , 2007 , Article)The effect of gamma-irradiation on the structure of polymethyl methacrylate (PMMA) has been investigated. In this study, the PMMA specimens were gamma-irradiated at doses in the range of 0-1000 kGy and measured by means ... -
An upper bound of the basis number of the semi-strong product of cycles with bipartite graphs
( The Korean Mathematical Society , 2007 , Article)An upper bound of the basis number of the semi-strong product of cycles with bipartite graphs is given. Also, an example is presented where the bound is achieved. -
Weighted estimates for rough parametric Marcinkiewicz integrals
( Korean Mathematical Society , 2007 , Article)We establish a weighted norm inequality for a class of rough parametric Marcinkiewicz integral operators . As an application of this inequality, we obtain weighted inequalities for a class of parametric Marcinkiewicz ... -
A rich learning lesson using the Poisson distribution
( Elsevier B.V. , 2007 , Article)In this note, we explore the rich information about inference that the Poisson distribution has. The source of this information is mainly the fact that the mean and variance of this distribution are equal. -
A simple method for finding empirical likelihood type intervals for the ROC curve
( Wayne State University , 2007 , Article)Interval estimation of the ROC curve is considered using the empirical likelihood techniques. Suggested is a procedure that is very simple computationally and avoids the constrained optimization problems usually faced with ... -
Homotopy perturbation method for nonlinear partial differential equations of fractional order
( Elsevier B.V. , 2007 , Article)The aim of this Letter is to present an efficient and reliable treatment of the homotopy perturbation method (HPM) for nonlinear partial differential equations with fractional time derivative. The fractional derivative is ... -
Positron annihilation and ion beam analysis of ion-bombardment-induced hydrogen release and oxidation of ultra high molecular weight polyethylene
( Elsevier , 2007 , Article)Ultra high molecular weight polyethylene was bombarded with He+ and Ar+ ions to fluences ranging from 1013 to 2×1016 ions/cm2. Rutherford backscattering and nuclear reaction analysis were applied to study mechanism of ... -
A generalized differential transform method for linear partial differential equations of fractional order
( Elsevier B.V. , 2007 , Article)In this letter we develop a new generalization of the two-dimensional differential transform method that will extend the application of the method to linear partial differential equations with space- and time-fractional ... -
Application of generalized differential transform method to multi-order fractional differential equations
( Elsevier , 2007 , Article)In a recent paper [Odibat Z, Momani S, Erturk VS. Generalized differential transform method: application to differential equations of fractional order, Appl Math Comput. submitted for publication] the authors presented a ... -
Numerical comparison of methods for solving a special fourth-order boundary value problem
( Elsevier Inc. , 2007 , Article)In this paper, we implement relatively new analytical techniques, the differential transform method, Adomian decomposition, and homotopy perturbation method, for solving a fourth-order boundary value problem. In these ... -
Solving systems of fractional differential equations using differential transform method
( Elsevier B.V. , 2007 , Article)This paper presents approximate analytical solutions for systems of fractional differential equations using the differential transform method. The fractional derivatives are described in the Caputo sense. The application ...