In this study, various thicknesses of Pd catalytic films were deposited on Ti/Si substrates and pretreated with NH/sub 3/. The effects of catalyst deposition parameters and NH/sub 3/ pretreatment time (0, 1, and 10 mi...
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In this study, various thicknesses of Pd catalytic films were deposited on Ti/Si substrates and pretreated with NH/sub 3/. The effects of catalyst deposition parameters and NH/sub 3/ pretreatment time (0, 1, and 10 minutes) on the size distribution of Pd catalytic particles, and subsequently, on the diameter and density of synthesized carbon nanotubes (CNTs) were investigated. The CNTs were synthesized by thermal CVD at 750/spl deg/C using methane (CH/sub 4/) as the carbon source, and a mixture of Ar/H/sub 2/ (80 vol.%/20 vol.%) as the carrier gas.
In this paper, the study of thermal CVD grown CNT field emitters in a triode amplifier configuration is reported. The DC characteristics of the CNT triode are investigated, including I/sub a/ vs. V/sub a/ for differen...
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In this paper, the study of thermal CVD grown CNT field emitters in a triode amplifier configuration is reported. The DC characteristics of the CNT triode are investigated, including I/sub a/ vs. V/sub a/ for different V/sub g/. Moreover, DC parameters such as transconductance, amplification factor and anode resistance of the triode amplifier are determined. It was shown that a higher amplification factor can be achieved with optimum gate-anode-cathode spacing such that the cathode is effectively shielded from the anode by the gate but the anode still collects all electrons emitted from the cathode. High emission current at low gate voltage is key to achieving high transconductance. This can be obtained by optimum configuration of high-density CNTs array in a triode structure with a common gate.
We present a functional and structural didactic simulator of Cache Memory Systems developed at the Pontifical Catholic University of Minas Gerais, Brazil. The development occurred during the undergraduatecomputer Arc...
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This paper proposes the development of a fuzzy predictive control. Genetic algorithms (GA's) are used to automatically tune the controller. A recurrent neural network is used to identify the process, and then prov...
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This paper proposes the development of a fuzzy predictive control. Genetic algorithms (GA's) are used to automatically tune the controller. A recurrent neural network is used to identify the process, and then provides predictions about the process behavior, based on control actions applied to the system. These predictions are used by the fuzzy controller, in order to accomplish a better control of an alcoholic fermentation process from chemical industry. This problem has been chosen due to its non-linearity and large accommodation time, that make it hard to control by standard controllers. Comparison of performance is made with non-predictive approaches(PID and Fuzzy-PD), and also with another predictive approach, GPC(Generalized Predictive Control).
High dimensional inputs coupled with scarcity of labeled data are among the greatest challenges for classification of hyperspectral data. These problems are exacerbated if the number of classes is large. High dimensio...
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High dimensional inputs coupled with scarcity of labeled data are among the greatest challenges for classification of hyperspectral data. These problems are exacerbated if the number of classes is large. High dimensional output classes can often be handled effectively by decomposition into multiple two-(meta)class problems, where each sub-problem is solved using a suitable binary classifier, and outputs of this collection of classifiers are combined in a suitable manner to obtain the answer to the original multi-class problem. This approach is taken by the binary hierarchical classifier (BHC). The advantages of the BHC for output decomposition can be further exploited for hyperspectral data analysis by integrating a feature selection methodology with the classifier. Building upon the previously developed best bases BHC algorithm with greedy feature selection, a new method is developed that selects a subset of band groups within metaclasses using reactive tabu search. Experimental results obtained from analysis of Hyperion data acquired over the Okavango Delta in Botswana are superior to those of the greedy feature selection approach and more robust than either the original BHC or the BHC with greedy feature selection.
In this paper we analyze the use of research activities as learning instrument in electricalengineering and computer science. This pedagogic approach was applied in undergraduate disciplines, undergraduate teaching a...
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In this paper we analyze the use of research activities as learning instrument in electricalengineering and computer science. This pedagogic approach was applied in undergraduate disciplines, undergraduate teaching assistance and undergraduate research projects. Our main goals are optimize the learning process using research and motivate the use of research activities as learning instrument.
Aboard current ships, such as the DDG 51, engineering control and damage control activities are manpower intensive. It is anticipated that, for future combatants, the workload demand arising from operation of systems ...
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Aboard current ships, such as the DDG 51, engineering control and damage control activities are manpower intensive. It is anticipated that, for future combatants, the workload demand arising from operation of systems under conditions of normal steaming and during casualty response will need to be markedly reduced via automated monitoring, autonomous control, and other technology initiatives. Current DDG 51 class ships can be considered as a manpower baseline and under Condition III typical engineering control involves seven to eight watchstanders at manned stations in the Central Control Station, the engine rooms and other machinery spaces. In contrast to this manning level, initiatives such as DD 21 and the integrated engineering plant (IEP) envision a partnership between the operator and the automation system, with more and more of the operator's functions being shifted to the automation system as manning levels decrease. This paper describes some human systems integration studies of workload demand reduction and, consequently, manning reduction that can be achieved due to application of several advanced technology concepts. Advanced system concept studies in relation to workload demand are described and reviewed including. Piecemeal applications of diverse automation and remote control technology concepts to selected high driver tasks in current DDG 51 activities. Development of the reduced ship's crew by virtual presence system that will provide automated monitoring and display to operators of machinery health, compartment conditions, and personnel health. The IEP envisions the machinery control system as a provider of resources that are used by various consumers around the ship. Resource needs and consumer priorities are at all times dependent upon the ship's current mission and the availability of equipment pawnbrokers.
作者:
Vieira, Luis CarlosPrograma de Pós-Graduação em Engenharia Elétrica e Informática Industrial
Departamento de Eletrônica e Telecomunicações (Graduate Program in Electrical Engineering and Industrial Computer Science Department of Electronics and Telecommunications) Centro Federal de Educação Tecnológica do Paraná (Federal Center of Technological Education of Paraná) Curitiba Brazil
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