4,459 research outputs found

    Algebraic grid adaptation method using non-uniform rational B-spline surface modeling

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    An algebraic adaptive grid system based on equidistribution law and utilized by the Non-Uniform Rational B-Spline (NURBS) surface for redistribution is presented. A weight function, utilizing a properly weighted boolean sum of various flow field characteristics is developed. Computational examples are presented to demonstrate the success of this technique

    Meningkatkan Kemampuan Siswa Kelas V SD Inpres Mayayap Dalam Menulis Karangan Narasi Melalui Model Pembelajaran Kooperatif

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    Kesulitan dalam menemukan ide, menuangkan ide, mengembangkan ide dan merangkai kata atau kalimat dengan tepat menjadi masalah yang mendasar bagi siswa kelas V SD Inpres Mayayap dalam menulis karangan narasi. Tujuan penelitian ini adalah untuk mengetahui penggunaan model pembelajaran kooperatif dalam meningatkan kemampuan siswa kelas V menulis karangan narasi di SD Inpres Mayayap. Populasi dalam penelitian adalah siswa kelas V SD Inpres Mayayap (hanya 1 kelas) yang berjumlah 20 orang. Hasil penelitian menunjukkan bahwa aktivitas guru dan siswa mengalami peningkatan yang cukup berarti dari siklus I ke siklus II dan untuk analisis tes akhir tindakan dari siklus I ke siklus II terjadi juga peningkatan belajar klasikal sebesar 40% yaitu 55% pada siklus I menjadi 95% pada siklus II. Berdasarkan hasil tersebut dapat disimpulkan bahwa dengan model pembelajaran kooperatif dapat meningkatkan kemampuan siswa kelas V SD Inpres Mayayap dalam menulis Karangan Narasi

    Einstein's mirror revisited

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    We describe a simple geometrical derivation of the formula for reflection of light from a uniformly moving plane mirror directly from the postulates of special relativity.Comment: 4 pages, 5 figures, RevTeX4, comments welcome; V2: corrected Fig. 5 and the discussion associated with it, co-author include

    QQˉQ\bar Q (Q∈{b,c}Q\in \{b, c\}) spectroscopy using Cornell potential

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    The mass spectra and decay properties of heavy quarkonia are computed in nonrelativistic quark-antiquark Cornell potential model. We have employed the numerical solution of Schr\"odinger equation to obtain their mass spectra using only four parameters namely quark mass (mcm_c, mbm_b) and confinement strength (AccˉA_{c\bar c}, AbbˉA_{b\bar b}). The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are computed perturbatively to determine the mass spectra of excited SS, PP, DD and FF states. Digamma, digluon and dilepton decays of these mesons are computed using the model parameters and numerical wave functions. The predicted spectroscopy and decay properties for quarkonia are found to be consistent with available experimental observations and results from other theoretical models. We also compute mass spectra and life time of the BcB_c meson without additional parameters. The computed electromagnetic transition widths of heavy quarkonia and BcB_c mesons are in tune with available experimental data and other theoretical approaches

    Optical Non-Contact Railway Track Measurement with Static Terrestrial Laser Scanning to Better than 1.5mm RMS

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    The railway industry requires track to be monitored for a variety of reasons, particularly when any type of physical works take place within the vicinity of the asset (e.g. demolition, construction and redevelopment works). Terrestrial laser scanning (TLS) has considerable potential as a survey method for rail measurement due to its non-contact nature and independence from physical targeting at track level. The consensus from recently published work using static terrestrial laser scanning is that rail measurements to the order of 3mm RMS are routinely possible. Such measures are appropriate for extracting the gauge, cant and twist parameters required by the rail industry, however engineering specifications designed to ensure safe and comfortable running of the trains ideally require measurements of better quality. This paper utilises standard design rail profiles from the UK industry to optimise the way in which TLS point cloud data are fitted to the rail geometry. The work is based on the use of off the shelf phase-based TLS systems each capable of delivering single point measurements of the order of 5mm to cooperative surfaces. The paper describes a workflow which focuses the fitting process onto discrete planar rail elements derived from the design rail geometry. The planar fitting process is improved through understanding how data from these scanners respond to rail surfaces. Of particular importance is the removal of noisy data from the shiny running surfaces. Results from a sequence of multi-station TLS surveys of the same set of double tracks taken from platform level highlight the capability to obtain fits to the rail model of better than 1.5mm RMS. Whilst fitting can be carried out on a single side of a rail, the paper highlights the challenge of obtaining an accurate TLS registration necessary to extract both sides of each rail to the same level of accuracy. This configuration is proven over inter-TLS instrument separations of the order of 30m and demonstrates the TLS network coverage necessary to achieve such results even in the presence of an occluding electric third rail

    Analysis of a Radar system for UAV Tracking using MATLAB

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    Volume 7 Issue 6 (June 201

    PYRIMIDINE INCORPORATED SCHIFF BASE OF ISONIAZID WITH THEIR SYNTHESIS, CHARACTERIZATION AND IN VITRO BIOLOGICAL EVALUATION

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      Objective: Versatile biological activities of nitrogen containing heterocycles in medicinal chemistry, mainly pyrimidine and pyridine ring based heterocyclic moieties are very important. Pharmaceutical important of pyrimidine and isoniazid moiety prompted us to synthesize isoniazid clubbed pyrimidine derivatives and evaluated for antimicrobial and antituberculosis activity.Method: 2-(2-(3-bromo benzylidene)-1-isonicotinoyl hydrazinyl)-N-(4-(substituted phenyl)-6-(substituted aryl) pyrimidin-2-yl) acetamide 2(A-J) have been synthesized by condensation reaction of 2-chloro-N-[4-(substituted phenyl)-6-(substituted aryl) pyrimidin-2-yl] acetamide and N'-[(E)- (3-bromophenyl) methylidene]pyridine-4-carbohydrazide. All newly synthesized compounds were screened for in vitro antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus pyogenes, antifungal against Candida albicans, Aspergillus niger, and Aspergillus clavatus, and antituberculosis activity against Mycobacterium tuberculosis H37RV.Results: Majority of the compounds exhibited good antibacterial, antifungal, and antituberculosis activity. All titled compounds were characterized by spectral analyses (infrared spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectroscopy).Conclusion: 2-(2-(3-bromo benzylidene)-1-isonicotinoyl hydrazinyl)-N-(4-(substituted phenyl)-6-(substituted aryl) pyrimidin-2-yl) acetamide 2(A-J) showed good antimicrobial activity and comparatively good antituberculosis activity. Hence, all the compounds of this series considered for future investigation mainly in area of antibacterial, antifungal study
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