5,338 research outputs found

    Investigation of Aerodynamic Alterations for Improving the KC-135 Boom Performance during Aerial Refueling

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    This study investigated the eligibility of the KC-135 air refueling boom for improved capabilities in the areas of control and performance. By using a thick airfoil cross-section for the boom tube, rather than the current circular cross-section, the ability to increase the lift characteristics was verified Prior compiled test data was used for comparison against analytical computer solutions. The possibility and effects of control frequency oscillations were also examined due to the unstable nature of the flow at test conditions. Additionally, the effect of other cross-section shapes, such as the blunt fairing, on the size of the flyable envelope for the trailing aircraft was investigated by using FORTRAN coding. Results show that the KC-135 air refueling boom can be modified for better lift and performance envelope capabilities

    Fabrication and Application of a Polymer Neuromorphic Circuitry Based on Polymer Memristive Devices and Polymer Transistors

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    Neuromorphic engineering is a discipline that aims to address the shortcomings of today\u27s serial computers, namely large power consumption, susceptibility to physical damage, as well as the need for explicit programming, by applying biologically-inspired principles to develop neural systems with applications such as machine learning and perception, autonomous robotics and generic artificial intelligence. This doctoral dissertation presents work performed fabricating a previously developed type of polymer neuromorphic architecture, termed Polymer Neuromorphic Circuitry (PNC), inspired by the McCulloch-Pitts model of an artificial neuron. The major contribution of this dissertation is a development of processing techniques necessary to realize the Polymer Neuromorphic Circuitry, which required a development of individual polymer electronics elements, as well as customization of fabrication processes necessary for the realization of the circuitry on separate substrates as well as on a single substrate. This is the first demonstration of a fabrication of an entire neuron, and more importantly, a network of such neurons, that includes both the weighting functionality of a synapse and the somatic summing, all realized with polymer electronics technology. Polymer electronics is a new branch of electronics that is based on conductive and semi-conductive polymers. These new elements hold a great advantage over the conventional, inorganic electronics in the form of physical flexibility, low cost and ease of fabrication, manufacturing compatibility with many substrate materials, as well as greater biological compatibility. These advantages were the primary motivation for the choice to fabricate all of the electrical components required to realize the PNC, namely polymer transistors, polymer memristive devices, and polymer resistors, with polymer electronics components. The efficacy of this design is validated by demonstrating that the activation function of a single neuron approximates the sigmoidal function commonly employed by artificial neural networks. The utility of the neuromorphic circuitry is further corroborated by illustrating that a network of such neurons, and even a single neuron, are capable of performing linear classification for a real-life problem

    Simulation, Application, and Resilience of an Organic Neuromorphic Architecture, Made with Organic Bistable Devices and Organic Field Effect Transistors

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    This thesis presents work done simulating a type of organic neuromorphic architecture, modeled after Artificial Neural Network, and termed Synthetic Neural Network, or SNN. The first major contribution of this thesis is development of a single-transistor-single-organic-bistable-device-per-input circuit that approximates behavior of an artificial neuron. The efficacy of this design is validated by comparing the behavior of a single synthetic neuron to that of an artificial neuron as well as two examples involving a network of synthetic neurons. The analysis utilizes electrical characteristics of polymer electronic elements, namely Organic Bistable Device and Organic Field Effect Transistor, created in the laboratory at University of Denver. Polymer electronics is a new branch of electronics that is based on conductive and semi-conductive polymers. These new elements hold a great advantage over the inorganic electronics in the form of physical flexibility and low cost of fabrication. However, their device variability between individual devices is also much greater. Therefore the second major contribution of this thesis is the analysis of resilience of neural networks subjected to physical damage and other manufacturing faults

    Hydrologic characteristics of shallow bedrock aquifers in the vicinity of Norman Creek, central Phelps County, Missouri

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    Groundwater is becoming increasingly important as a source of water supply in the United States. Consequently, the prediction of well yields is a vital concern. In order to predict the quantity of water which can be reduced from a given aquifer it is necessary to know the aquifer\u27s hydrologic characteristics. Many theoretical formulae have been derived for determining the aquifer characteristics. To date, these formulae have been tested mainly on unconsolidated and clastic rock aquifers. It has never been shown that these formulae can also be consistently applied to carbonate aquifers which underlie regions of karst terrain. This paper summarizes various theoretical formulae, equilibrium, non-equilibrium, partially penetrating, and fully penetrating, and applied them to data obtained from pumping tests of shallow wells drilled in a region of carbonate karst terrain. The non-equilibrium formulae, both partially and fully penetrating, produced similar results, but there was sometimes a wide variation between these results and those obtained through use of the equilibrium formulae. Modifying effects, such as the presence of recharge, were also found to exist. Aquifer yields were not generally high, although the shallow wells drilled might be adequate for limited personal consumption --Abstract, page ii

    75/Stosowanie G-CSF w trakcie chemioradioterapii – ocena bezpieczeństwa

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    CelCelem pracy była ocena bezpieczeństwa i skuteczności podawania G-CSF (Neupogen, Granocyt) w trakcie jednoczasowej chemioradioterapii. Stosowanie białokrwinkowych czynników wzrostu jest rekomendowane u chorych otrzymujących chemioterapię, u których dochodzi do neutropenii z gorączką neutropeniczną lub profilaktycznie w przypadku wybranych programów chemioterapii (np. tzw. dose dense chemotherapy w chłoniakach i raku piersi). Ze względu na brak publikacji na temat stosowania G-CSF i GM-CSF w trakcie radioterapii nie jest ono rekomendowane w przypadku jednoczasowej chemioradioterapii. Zauważono (dwa doniesienia zjazdowe), że stosowanie czynników wzrostu w trakcie chemioradioterapii może prowadzić do małopłytkowości,szczególnie w przypadku napromieniania regionu klatki piersiowej, jednak mechanizm pozostaje nieznany.Materiał i metodykaW okresie od sierpnia 2003 do kwietnia 2004 w Zakładzie i Oddziale Radioterapii w Olsztynie u 25 chorych leczonych w sposób skojarzony (chemioradioterapia jednoczasowa) stosowano w trakcie radioterapii granocyt, w celu zminimalizowania przerw w leczeniu i podania chemioterapii w zaplanowanym czasie. W grupie leczonych większość stanowili chorzy na raka płuca (12 chorych), poza tym leczono 5 chorych na raka głowy i szyi, 4 chore z rakiem piersi, 3 chore z nowotworami narządu rodnego oraz jednego chorego na raka odbytnicy. G-CSF podawano chorym od 3 do 7 dni (średnio 5dni).WynikiPodawanie G-CSF ograniczyło przerwy w leczeniu i nie spowodowało żadnych poważnych objawów ubocznych. W kontrolnych morfologiach, po zakończeniu podawania granocytu, spadek wartości płytek krwi zaobserwowano u dwóch chorych, jednak nie były to wartości wymagające interwencji.WnioskiStosowanie G-CSF w trakcie chemioradioterapii, w celu zminimalizowania przerw w leczeniu, wydaje się bezpieczne i nie powoduje trombocytopenii. Ze względu na niewielką grupę chorych uzasadnione wydaje się przeprowadzenie badania prospektywnego II fazy

    Optical manipulation of a single Mn spin in a CdTe-based quantum dot

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    A system of two coupled CdTe quantum dots, one of them containing a single Mn ion, was studied in continuous wave and modulated photoluminescence, photoluminescence excitation, and photon correlation experiments. Optical writing of information in the spin state of the Mn ion has been demonstrated, using orientation of the Mn spin by spin-polarized carriers transferred from the neighbor quantum dot. Mn spin orientation time values from 20 ns to 100 ns were measured, depending on the excitation power. Storage time of the information in the Mn spin was found to be enhanced by application of a static magnetic field of 1 T, reaching hundreds of microseconds in the dark. Simple rate equation models were found to describe correctly static and dynamical properties of the system.Comment: 4 pages, 3 figure
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