3,681 research outputs found

    Color image processing and object tracking workstation

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    A system is described for automatic and semiautomatic tracking of objects on film or video tape which was developed to meet the needs of the microgravity combustion and fluid science experiments at NASA Lewis. The system consists of individual hardware parts working under computer control to achieve a high degree of automation. The most important hardware parts include 16 mm film projector, a lens system, a video camera, an S-VHS tapedeck, a frame grabber, and some storage and output devices. Both the projector and tapedeck have a computer interface enabling remote control. Tracking software was developed to control the overall operation. In the automatic mode, the main tracking program controls the projector or the tapedeck frame incrementation, grabs a frame, processes it, locates the edge of the objects being tracked, and stores the coordinates in a file. This process is performed repeatedly until the last frame is reached. Three representative applications are described. These applications represent typical uses and include tracking the propagation of a flame front, tracking the movement of a liquid-gas interface with extremely poor visibility, and characterizing a diffusion flame according to color and shape

    Mixing fuel particles for space combustion research using acoustics

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    Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. The experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20 sec low gravity trajectory are described. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity

    Fractional variational calculus of variable order

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    We study the fundamental problem of the calculus of variations with variable order fractional operators. Fractional integrals are considered in the sense of Riemann-Liouville while derivatives are of Caputo type.Comment: Submitted 26-Sept-2011; accepted 18-Oct-2011; withdrawn by the authors 21-Dec-2011; resubmitted 27-Dec-2011; revised 20-March-2012; accepted 13-April-2012; to 'Advances in Harmonic Analysis and Operator Theory', The Stefan Samko Anniversary Volume (Eds: A. Almeida, L. Castro, F.-O. Speck), Operator Theory: Advances and Applications, Birkh\"auser Verlag (http://www.springer.com/series/4850

    Stationarity-conservation laws for certain linear fractional differential equations

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    The Leibniz rule for fractional Riemann-Liouville derivative is studied in algebra of functions defined by Laplace convolution. This algebra and the derived Leibniz rule are used in construction of explicit form of stationary-conserved currents for linear fractional differential equations. The examples of the fractional diffusion in 1+1 and the fractional diffusion in d+1 dimensions are discussed in detail. The results are generalized to the mixed fractional-differential and mixed sequential fractional-differential systems for which the stationarity-conservation laws are obtained. The derived currents are used in construction of stationary nonlocal charges.Comment: 28 page

    Morphological-developmental reaction and productivity of plants and canopy of semileafless pea (Pisum sativum L.) after seed vaccination with Rhizobium and foliar micronutrient fertilization

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    The determinants of semileafless peas (Pisum sativum> L., cv. Tarchalska) crop productivity were studied during two vegetative seasons: cool 2010 and warm 2011 in south part of Poland (Modzurów 50°09’N 18°07’E; 274 m. a.s.l.. Peas was treated either with seed vaccine (NitraginaTM) containing Rhizobium bacteria or foliar micronutrient fertilizer (PhotrelTM) or both of them. The range of peas response to treatments included biometrical measurements and also the measurements of vegetation indices namely, green area index (GAI), normalized difference vegetation index (NDVI) and relative chlorophyll content (SPAD), carried out in the specific stages of development, which for the compared objects were generally insignifi cant. In the warmer growing season, pea plants grew better, what resulted in a very high yield of seeds per plant, determined by a greater number of large seeds. It was shown that the length and weight of pea pod and the number of seeds formed in the pod depends on its position on the particular node. The longest pods, characterized by the greatest weight and number of seeds, developed on the lower nodes: 1st and 2nd one. The pea pods forming on higher nodes, from the 3rd, had reduced number of fruits and the weight of a single seed. The shortest pods were growing out of the 5th and 6th nodes, at the top of the stem. Analysis of the single pea seed mass shows a highly significant effect of its position in the fruit on pod productivity. Seeds located in the central part of the pod had the greatest mass, and this accuracy, as highly significant, was found for the pods containing from 3 to 8 seeds. The tested agrochemical treatments did not differentiate the chemical composition of seeds

    Quantitative rainbow schlieren deflectometry

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    In the rainbow schlieren apparatus, a continuously graded rainbow filter is placed in the back focal plane of the decollimating lens. Refractive-index gradients in the test section thus appear as gradations in hue rather than irradiance. A simple system is described wherein a conventional color CCD array and video digitizer are used to quantify accurately the color attributes of the resulting image, and hence the associated ray deflections. The present system provides a sensitivity comparable with that of conventional interferometry, while being simpler to implement and less sensitive to mechanical misalignment

    Color Image Processing and Object Tracking System

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    This report describes a personal computer based system for automatic and semiautomatic tracking of objects on film or video tape, developed to meet the needs of the Microgravity Combustion and Fluids Science Research Programs at the NASA Lewis Research Center. The system consists of individual hardware components working under computer control to achieve a high degree of automation. The most important hardware components include 16-mm and 35-mm film transports, a high resolution digital camera mounted on a x-y-z micro-positioning stage, an S-VHS tapedeck, an Hi8 tapedeck, video laserdisk, and a framegrabber. All of the image input devices are remotely controlled by a computer. Software was developed to integrate the overall operation of the system including device frame incrementation, grabbing of image frames, image processing of the object's neighborhood, locating the position of the object being tracked, and storing the coordinates in a file. This process is performed repeatedly until the last frame is reached. Several different tracking methods are supported. To illustrate the process, two representative applications of the system are described. These applications represent typical uses of the system and include tracking the propagation of a flame front and tracking the movement of a liquid-gas interface with extremely poor visibility

    A formulation of the fractional Noether-type theorem for multidimensional Lagrangians

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    This paper presents the Euler-Lagrange equations for fractional variational problems with multiple integrals. The fractional Noether-type theorem for conservative and nonconservative generalized physical systems is proved. Our approach uses well-known notion of the Riemann-Liouville fractional derivative.Comment: Submitted 26-SEP-2011; accepted 3-MAR-2012; for publication in Applied Mathematics Letter
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