837 research outputs found

    Design Techniques for R-717, R-22, and R-12 Shell-and-Coil Subcoolers and Intercoolers

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    External lightning protection system for wind turbine blades - power performance

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    Previous studies conducted by the authors on the aerodynamic performance of turbine blades have shown unfavourable effects of externally mounted lightning down conductors. Owing to this, one could ask whether or not externally mounted lightning down conductors could linearly affect the power performance of the whole wind turbine as well. Therefore, this paper presents a study of the power performance of one wind turbine with an externally mounted lightning down conductor. An untwisted blade profile of NACA 4418 with and without external conductor was used on the full wind turbine model. Numerical simulations were carried out on turbine power output derived from Blade Element Momentum (BEM) theory. The results are compared and discussed. The preliminary results indicate that degradation in power performance may not be significant

    Pengaruh Model Pembelajaran Berbasis Masalah Terhadap Hasil Belajar Fisika Siswa Kelas X Sman 2 Praya Tahun Pelajaran 2015/2016

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    – The purpose of this study was to investigate the influence of problem based learning model toward physics learning outcomes at SMAN 2 Praya grade X at the academic year 2015/2016. This study was experiment with post-test only control group design. The population of this study were all students of Xth grade with number of students were 400 students. Cluster random sampling was used to choose the class sample with X-4 as experiment class and X-6 as control class. The instrument of this study used multiple choise test with 5 alternative answer. Based from the result, data were analyzed using t-test polled varians. The data obtained 3.42 for the t-hint and 1.99 for the t-table with significant level 5%. Therefore t-hint > t-table, the H0 rejected and Ha be accepted. This result shows that problem based learning model is influencing the stuent's physics academy result at SMAN 2 Praya Xth grade academic year 2015/2016

    Fallout radionuclides as indicators of soil degradation and potential loss of agricultural production in Latin American and Caribbean countries

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    Land degradation affects about 300 million ha of land in the Latin American and Caribbean region: 51% of this is agricultural land (180 million hectares). The ARCAL Regional Strategy Profile identifies the deficient use of agricultural soil and the resulting permanent loss of productive agricultural areas as one of the most important environmental and alimentary problems in the Latin American and Caribbean continental areas (Alimentary Security, A3, PER-ARCAL, 2007-2013). In recent times, extensive natural areas have been dramatically diminished by various human interventions. In this continental context, regional or national difficulties normally present specific characteristics and relevancies and distinct intervention needs. Indicators of the present soil conservation status are essential for an assessment of national economic impact and an evaluation of social consequences.Fil: Lohaiza, Flavia Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis ; ArgentinaFil: Juri Ayub, J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis ; ArgentinaFil: Velasco, H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis ; ArgentinaFil: Dercon, G.. International Atomic Energy Agency. Department of Nuclear Sciences and Applications. Soil and Water Management & Crop Nutrition Subprogramme; Austri

    Wilson\u27s disease: experience at a tertiary care hospital.

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    Wilson\u27s disease (WD) is a rare autosomal recessive disorder of copper metabolism. Data regarding WD is not available from Pakistan. A cross-sectional study was conducted at The Aga Khan University Hospital, Karachi, and all patients admitted with primary and secondary diagnosis of Wilson\u27s disease were added. A total of 47 patients were seen; 68% (n = 32) were male. The mean age was 26.6 ± 9.97 years. Most of the patients presented with hepatic, (n = 22, 46.8%), neurological, (n = 17, 36.2%) and psychiatric (n = 8, 17%) symptoms. Mean ceruloplasmin level was 0.17 ± 0.13 g/dl; it was \u3c 0.25 g/dl in 39 (86.6%) patients. Serum copper (Cu) was reduced in 32 (68.1%) patients and 24-hr-urinary Cu was raised in 22 (47.6%) patients. Slit lamp examination for Kayser-Fleischer (KF) rings was done on 15 (31.9%) patients and 9 (60%) of them had KF rings. Mean serum aspartate transaminase (AST) / alanine transaminases (ALT) ratio was 1.92 and median alkaline phosphatase / total bilirubin ratio was 79.30 (IQR 35.05; 166.50)

    Tuberculosis of the Gallbladder

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    Analysis of 5 patients with gallbladder tuberculosis who had open cholecystectomy and review of literature have shown that, although still rare it presents as a part of systemic miliary tuberculosis, abdominal tuberculosis, isolated gallbladder tuberculosis and as acalculus cholecystitis in anergic patients. There are no pathognomonic signs, the diagnosis depends on suspicion of tuberculosis, peroperative findings and histological examination

    Kurdish Dialect Recognition using 1D CNN

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    Dialect recognition is one of the most attentive topics in the speech analysis area. Machine learning algorithms have been widely used to identify dialects. In this paper, a model that based on three different 1D Convolutional Neural Network (CNN) structures is developed for Kurdish dialect recognition. This model is evaluated, and CNN structures are compared to each other. The result shows that the proposed model has outperformed the state of the art. The model is evaluated on the experimental data that have been collected by the staff of department of computer science at the University of Halabja. Three dialects are involved in the dataset as the Kurdish language consists of three major dialects, namely Northern Kurdish (Badini variant), Central Kurdish (Sorani variant), and Hawrami. The advantage of the CNN model is not required to concern handcraft as the CNN model is featureless. According to the results, the 1 D CNN method can make predictions with an average accuracy of 95.53% on the Kurdish dialect classification. In this study, a new method is proposed to interpret the closeness of the Kurdish dialects by using a confusion matrix and a non-metric multi-dimensional visualization technique. The outcome demonstrates that it is straightforward to cluster given Kurdish dialects and linearly isolated from the neighboring dialects

    Excitation of surface plasmons in thin noble metallic film of copper, silver and gold paper

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    The formation of surface plasmons in a different type of noble metallic film was successfully simulated using MATLAB program software. The thicknesses of copper, silver and gold metal films were varied between 20 nm to 80 nm. The narrowness and depth of surface plasmon resonance (SPR) curves were observed to determine the excitation of surface plasmons. The simulation results indicate that the maximum excitation of surface plasmons can be achieved by using silver thin film with thicknesses of 50 nm at the minimum reflectivity of 0.0038 a.u and full width at half maximum value of 0.2592°. The silver film that produces a deeper and sharper SPR curve has potential in the development of a low cost and high sensitivity of SPR sensing device
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