958 research outputs found

    A Time Truncated Moving Average Chart for the Weibull Distribution

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    A control chart of monitoring the number of failures is proposed with a moving average scheme, when the life of an item follows a Weibull distribution. A specified number of items are put on a time truncated life test and the number of failures is observed. The proposed control chart has been evaluated by the average run lengths (ARLs) under different parameter settings. The control constant and the test time multiplier are to be determined by considering the in-control ARL. It is observed that the proposed control chart is more efficient in detecting a shift in the process as compared with the existing time truncated control chart. ? 2013 IEEE.11Ysciescopu

    Numerical Solutions of Odd Order Linear and Nonlinear Initial Value Problems Using a Shifted Jacobi Spectral Approximations

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    A shifted Jacobi Galerkin method is introduced to get a direct solution technique for solving the third- and fifth-order differential equations with constant coefficients subject to initial conditions. The key to the efficiency of these algorithms is to construct appropriate base functions, which lead to systems with specially structured matrices that can be efficiently inverted. A quadrature Galerkin method is introduced for the numerical solution of these problems with variable coefficients. A new shifted Jacobi collocation method based on basis functions satisfying the initial conditions is presented for solving nonlinear initial value problems. Through several numerical examples, we evaluate the accuracy and performance of the proposed algorithms. The algorithms are easy to implement and yield very accurate results

    A Shifted Jacobi-Gauss Collocation Scheme for Solving Fractional Neutral Functional-Differential Equations

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    The shifted Jacobi-Gauss collocation (SJGC) scheme is proposed and implemented to solve the fractional neutral functional-differential equations with proportional delays. The technique we have proposed is based upon shifted Jacobi polynomials with the Gauss quadrature integration technique. The main advantage of the shifted Jacobi-Gauss scheme is to reduce solving the generalized fractional neutral functional-differential equations to a system of algebraic equations in the unknown expansion. Reasonable numerical results are achieved by choosing few shifted Jacobi-Gauss collocation nodes. Numerical results demonstrate the accuracy, and versatility of the proposed algorithm

    Fast Spectral Collocation Method for Solving Nonlinear Time-Delayed Burgers-Type Equations with Positive Power Terms

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    Since the collocation method approximates ordinary differential equations, partial differential equations, and integral equations in physical space, it is very easy to implement and adapt to various problems, including variable coefficient and nonlinear differential equations. In this paper, we derive a Jacobi-Gauss-Lobatto collocation method (J-GL-C) to solve numerically nonlinear time-delayed Burgers-type equations. The proposed technique is implemented in two successive steps. In the first one, we apply nodes of the Jacobi-Gauss-Lobatto quadrature which depend upon the two general parameters , and the resulting equations together with the two-point boundary conditions constitute a system of ordinary differential equations (ODEs) in time. In the second step, the implicit Runge-Kutta method of fourth order is applied to solve a system of ODEs of second order in time. We present numerical results which illustrate the accuracy and flexibility of these algorithms

    How does the new developed curriculum affect the perception of medical graduates at King Abdulaziz University about professionalism?

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    Background: In 2007 Faculty of Medicine (FOM), King Abdulaziz University (KAU) reoriented the medical curriculum and integrated professionalism. This study was conducted to assess the perception of professionalism attitudes by medical graduates who graduated from the new curriculum that incorporated the professionalism module and compare it to those who did not.Methods: This cross sectional study was conducted at the teaching hospital of the FOM, KAU using a modified version of the well-constructed questionnairedesigned to assess the student’s attitudes toward professionalism was distributed to all interns in the academic year of 2013-2014. Statistical analysis was carried out using Statistical Package of Social Science (SPSS) version 16.Results: Higher mean scores with significant differences in all aspects of professionalism were observed in interns graduated from the new curriculum when compared to those of the old one and was previously reported by Eldeek et al., (2012). The importance of adhering to high ethical and moral behavior and the need of humanity in the efficacy of the medical practice were the most significant attributes with effect size of 0.64 and 0.58 respectively. Studying in the clinical years represented the first helpful source of the participant to develop their perception about professionalism. Conclusion: The new developed curriculum at the FOM succeeded to improve the graduate perception about professionalism.

    A Predictive Structural Model of Standards-Based School Evaluation on Student Outcome

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    The current study examined the relationship between school leadership, school environment, teaching and learning strategies, and students’ performance on national assessment in math and science. In addition, it examined the mediating role of teaching and learning strategies in its relation to school leadership, school environment, and students’ performance in math and science as well. Study data was utilized from two datasets. First, the School Evaluation Standards scale (SES), which includes three subscales: school leadership, school environment, and teaching and learning strategies was utilized from a total of 711 schools that were randomly chosen from Saudi Arabia. Second, these school average scores in national assessment of math and science were collected. The finding revealed that there were direct and indirect effects of school leadership, school environment, teaching and learning strategies on students’ performance in math and science. Furthermore, teaching and learning strategies played as mediator between school leadership and school environment and students performance in math and science. The results of the research provided insights on how school evaluation standards (SES) affect academic performance and learning outcomes. Educational policy makers can benefit from the results of this study by evaluating school performance assessment standards and the level of practices to gauge the degree of application in real world practices and determine the room for improvements

    Identification of key claudin genes associated with survival prognosis and diagnosis in colon cancer through integrated bioinformatic analysis

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    The claudin multigene family is associated with various aberrant physiological and cellular signaling pathways. However, the association of claudins with survival prognosis, signaling pathways, and diagnostic efficacy in colon cancer remains poorly understood.Methods: Through the effective utilization of various bioinformatics methods, including differential gene expression analysis, gene set enrichment analysis protein-protein interaction (PPI) network analysis, survival analysis, single sample gene set enrichment analysis (ssGSEA), mutational variance analysis, and identifying receiver operating characteristic curve of claudins in The Cancer Genome Atlas colon adenocarcinoma (COAD).Results: We found that: CLDN2, CLDN1, CLDN14, CLDN16, CLDN18, CLDN9, CLDN12, and CLDN6 are elevated in COAD. In contrast, the CLDN8, CLDN23, CLDN5, CLDN11, CLDN7, and CLDN15 are downregulated in COAD. By analyzing the public datasets GSE15781 and GSE50760 from NCBI-GEO (https://www.ncbi.nlm.nih.gov/geo/), we have confirmed that CLDN1, CLDN2, and CLDN14 are significantly upregulated and CLDN8 and CLDN23 are significantly downregulated in normal colon, colon adenocarcinoma tumor, and liver metastasis of colon adenocarcinoma tissues from human samples. Various claudins are mutated and found to be associated with diagnostic efficacy in COAD.Conclusion: The claudin gene family is associated with prognosis, immune regulation, signaling pathway regulations, and diagnosis of COAD. These findings may provide new molecular insight into claudins in the treatment of colon cancer

    Up-conversion luminescence coupled to plasmonic gold nanorods for light harvesting and hydrogen production

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    The conversion of infrared light to visible-light which allows a larger fraction of sun-light to be used is needed to improve light-harvesting. In this work a tri-functional material composed of an up-converter (NaYF4–Yb–Tm), plasmonic gold nanorods and CdS was made photocatalytically active using 980 nm wavelength light for the reduction of H+ to H2.Peer ReviewedPostprint (author's final draft
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