220 research outputs found

    The correlation between reflective thinking skills towards problem solving and academic success in mathematics and geometry courses of high school students

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    Bu araştırmanın amacı, lise öğrencilerinin problem çözmeye yönelik yansıtıcı düşünme becerileri ile matematik ve geometri derslerindeki akademik başarıları arasındaki ilişkinin araştırılmasıdır. Bu nedenle bu araştırma ilişkisel tarama modelinde bir araştırma olup, betimsel bir çalışmadır. Yapılan araştırmada Pearson mo mentler çarpımı korelasyon analizin sonucunda lise öğrencilerinin problem çözmeye yönelik yansıtıcı düşünme becerileri ile matematik ve geometri derslerindeki akademik başarıları arasındaki pozitif yönde ve yüksek düzeyde anlamlı ilişkiler saptanmıştır. Ay rıca, yapılan doğrusal regresyon analizi sonucunda da öğrencilerinin problem çözmeye yönelik yansıtıcı düşünme becerileri değişkeninin, öğrencilerin matematik ve geometri derslerindeki akademik başarılarını anlamlı şekilde yordadığı görülmüştür.The purpose of this study was to examine the correlation between high school students reflective thinking skills towards problem solving and their academic success in mathematics and geometry courses. For this purpose, correlations survey method was adopted in this study in order to find answers to the research questions. According to Pearsons moments correlation analysis carried out in the study, it was found that there was a significant high correlation between students reflective thinking skills towards problem solving and their academic success in mathematics and geometry courses. On the other hand, according to the results of the regression analysis, it was found that students reflective thinking skills towards problem s olving predicted students their academic success in mathematics and geometry courses significantly

    Turner syndrome and associated problems in turkish children: A multicenter study

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    Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population. Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014. Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosi) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto’s thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%. Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespan. © Journal of Clinical Research in Pediatric Endocrinology

    Microstructural analysis with graded and non-graded indium in InGaN solar cell

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    In this study are graded and non graded InGaN/GaN samples grown on c-oriented sapphire substrate using the Metal Organic Chemical Vapour Deposition (MOCVD) technique. The structural and morphological properties of the grown InGaN/GaN solar cell structures are analyzed using High Resolution X-ray Diffraction (HRXRD), atomic force microscopy (AFM). Each structures c and a lattice parameters strain, biaxial strain, hydrostatic strain, stress, lattice relax, tilt angle, mosaic crystal size, dislocation densities of GaN and InGaN layers are determined by XRD measurements. In accordance with these calculations, the effect of graded structure on the defects, are discussed. As a dramatic result; although values of full width at half maximum (FWHM) are broad, a considerable decrease at dislocations is noticed. The AFM observations have revealed that the two dimensional growth of the graded sample is more significant and its roughness value is lower. JV measurements shown that the performance of the graded structure is higher. It is determined that all test results are consistent with each other. © Copyright 2017 by American Scientific Publishers. All rights reserved

    A Novel Alternating Cell Directions Implicit Method for the Solution of Incompressible Navier Stokes Equations on Unstructured Grids

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    In this paper, A Novel Alternating Cell Direction Implicit Method (ACDI) is researched which allows implementation of fast line implicit methods on quadrilateral unstructured meshes. In ACDI method, designated alternating cell directions are taken along a series of contiguous cells within the unstructured grid domain and used as implicit lines similar to Line Gauss Seidel Method (LGS). ACDI method applied earlier for the solution of potential flows is extended for the solution of the incompressible Navier-Stokes equations on unstructured grids. The system of equations is solved by using the Symmetric Line Gauss-Seidel (SGS) method along the alternating cell directions. Laminar flow fields over a single element NACA-0008 airfoil are computed by using structured and unstructured quadrilateral grids, and inviscid Euler flow solutions are given for the NACA-23012b multielement airfoil. The predictive capability of the method is validated against the data taken from the experimental or the other numerical studies and the efficiency of the ACDI method is compared with the implicit Point Gauss Seidel (PGS) method. In the selected validation cases, the results show that a reduction in total computation between 18% and 23% is achieved by the ACDI method over the PGS. In general, the results show that the ACDI method is a fast, efficient, robust and versatile method that can handle complicated unstructured grid cases with equal ease as with the structured grids

    Examination of the temperature related structural defects of InGaN/GaN solar cells

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    In this study the effects of the annealing temperature on the InGaN/GaN solar cells with different In-contents grown on sapphire substrate by the Metal Organic Chemical Vapor Deposition (MOCVD) are analyzed by High Resolution X-ray Diffraction (HRXRD) and an Atomic Force Microscope (AFM). The plane angles, mosaic crystal sizes, mixed stress, dislocation intensities of the structure of the GaN and InGaN layers are determined. According to the test results, there are no general characteristic trends observed due to temperature at both structures. There are fluctuating failures determined at both structures as of 350 °C. The defect density increased on the GaN layer starting from 350 °C and reaching above 400 °C. A similar trend is observed on the InGaN layer, too. © 2015 Elsevier Ltd. All rights reserved
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