In this paper, design algorithms for implementing controllers for DC to AC converter and DC to DC converter using Field Programmable Gate Arrays (FPGA) are presented. We used DC to AC converter proposed in [1], which ...
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ISBN:
(纸本)9781479964994
In this paper, design algorithms for implementing controllers for DC to AC converter and DC to DC converter using Field Programmable Gate Arrays (FPGA) are presented. We used DC to AC converter proposed in [1], which uses free oscillation and discrete energy injection technology for our experiments. For DC to DC converter, Cuk converter [2] was used in our experiments. The controller of DC to AC converter for different values of capacitors, for minimum switching losses on FPGA has been tested satisfactorily. The controller for DC to DC converter, to set the output voltage to a reference voltage irrespective of the input voltages has also been tested successfully.
The study of abstract models of computer systems using deterministic methods has produced sigmficant insight into the behavior of such systems in recent years This paper considers a model of a minicomputer network whi...
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The Taylor-Couette disc contactor is a hydrodynamic hybrid of a rotating disc contactor and a Taylor-Couette contactor. For application in reactive bioseparations, this type of liquid-liquid contactor may offer advant...
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The Taylor-Couette disc contactor is a hydrodynamic hybrid of a rotating disc contactor and a Taylor-Couette contactor. For application in reactive bioseparations, this type of liquid-liquid contactor may offer advantageous operation features. This paper summarizes the design characteristics of the Taylor-Couette disc contactor. For hydrodynamic characterization, experimental data of the mean Sauter diameter and dispersed-phase hold-up were compared with results predicted by empirical correlations, which were originally developed for rotating disc contactors. Several correlations were modified for the application on Taylor-Couette disc contactors. Operation characteristics have been deduced from mass-transfer experiments on the pilot-plant scale.
Encryption is a very important way to secure data in storage and communication, and it is a process of encoding messages or information in such a manner that only authorised persons can access it. Different techniques...
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Encryption is a very important way to secure data in storage and communication, and it is a process of encoding messages or information in such a manner that only authorised persons can access it. Different techniques are used to protect confidential image data against illicit access. In image encryption using chaotic systems, most authors use or design algorithms to generate the initial parameters' values from the secret key. However, as the key size depends on the number of these parameters, the used algorithms show little sensitivity to small changes in the key. To enhance both security and sensitivity in the choice of the initial parameters, this work combines the use of the Grain-128a stream cipher algorithm with two-dimensional Zaslavsky chaotic map. Firstly, the Grain-128a algorithm is applied to generate the required parameters of Zaslavsky's chaotic map from a fixed length 256-bit secret key. Secondly, the sequences generated by the chaotic map are used to encrypt the image using a bit confusion and diffusion process. The simulation results on greyscale, colour, binary, indexed, and medical images together with the scores obtained in the evaluation of the algorithm show that the proposed method is very sure and effective in encrypting images of any size and any type.
Utilizing a typology for space filling into what we call "soft" and "hard" methods, we introduce the central notion of "privacy sets" for dealing with the latter. This notion provides a u...
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Utilizing a typology for space filling into what we call "soft" and "hard" methods, we introduce the central notion of "privacy sets" for dealing with the latter. This notion provides a unifying framework for standard designs without replication, Latin hypercube designs, and Bridge designs, among many others. We introduce a heuristic algorithm based on privacy sets and compare its performance on some well-known examples. For instance, we demonstrate that for the computation of Bridge designs this algorithm performs significantly better than the state-of-the-art method. Moreover, the application of privacy sets is not restricted to cuboid design spaces and promises improvements for many other situations. (C) 2015 The Authors. Published by Elsevier B.V.
Die globale Erwärmung wird offensichtlich durch eine Membrane aus Industriegasen verursacht, die bei der konventionellen Energiegewinnung entstehen. Die zur Zeit vorherrschende Meinung besagt, dass die derzei...
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Die globale Erwärmung wird offensichtlich durch eine Membrane aus Industriegasen verursacht, die bei der konventionellen Energiegewinnung entstehen. Die zur Zeit vorherrschende Meinung besagt, dass die derzeitigen Naturkatastrophen Folgen dieser Umweltverschmutzung sind. Eine der Reaktionen der hochentwickelten Welt ist die Forcierung von erneuerbaren Energiequellen wie Biomasse, Wasser, Sonne und Wind. Wind ist definitive die wichtigste Alternative zu den fossilen Brennstoffen, und deshalb gehören Windkraftanlagen zu den wichtigsten Bauarten der nahen Zukunft. In diesem Beitrag wird The state of the art von Windkraftanlagen behandelt. Entsprechend dem hohen Stellenwert dieser turmartigen Massenbauwerke stehen dabei Lösungen ihrer beiden bautechnischen Fragen - Sicherheit und Wirtschaftlichkeit - im Vordergrund, untermauert durch drei Kernthemen: - Merkmale, Grundlagen, maßgebliche Tragrichtungen - vertikale Tragrichtung mit einem Erläuterungsbeispiel - horizontale Tragrichtung mit einem Erläuterungsbeispiel Der Aufsatz schließt mit Ausführungen über die aktuellen Herausforderungen und Entwicklungstendenzen der Energiegewinnung aus Windkraft. Wind Power Plants - Environment, design, outlook and scope. The today's world is confronted by two global threats: worming effect caused probably by the excessive use of fossil fuels and dependence on these becoming short sources of energy. The worming effect is caused by a membrane of gases produced among others during the conventional energy generation. There are voices claiming that some of the current natural disasters are consequences of such air pollution. One of the reactions of the highly developed world is use of renewable energy sources such as bio mass, water, sun and wind. Wind is definitive the most important alternatives to the fossil fuels and so wind mills belong to the most important structures of the near future. Consequently, the paper addresses the following major
Existing algorithms for the construction of exact D-optimum designs customarily search a list of candidate points. This article describes a computationally simple method of improving such designs. Tables are given of ...
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Existing algorithms for the construction of exact D-optimum designs customarily search a list of candidate points. This article describes a computationally simple method of improving such designs. Tables are given of designs for second-order models with as many as five factors found by search over candidate points. These are compared with designs already in the literature and used as the starting point for the adjustment algorithm.
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