This paper presents an improved switching strategy for three-phase full-bridge converters applied to switched reluctance motor (SRM) drives. The modified switching strategy is based on the idea that in every electrica...
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This paper presents an improved switching strategy for three-phase full-bridge converters applied to switched reluctance motor (SRM) drives. The modified switching strategy is based on the idea that in every electrical cycle the two switches in same leg of the converter alternate their commutating without using dead time. This drive method has several advantages including low cost, compactness, no dead time required, reduced number of switching pulses, and consequently reduced switching loss. The proposed method is analyzed and the experimental is investigated on 1.5 kW, three-phase 6/4 poles SRM which is designed for small electric vehicles by using standard three-phase full-bridge converter. The experimental results have confirmed an acceptable performance of this proposed technique.
Accurate iris detection is a crucial part of an iris recognition system. One of the main issues in iris segmentation is coping with occlusion that happens due to eyelids and eyelashes. In the literature, some various ...
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We propose a 3D nonparametric, entropy-based, coupled, multishape approach for the segmentation of subcortical brain structures in magnetic resonance images (MRI). Our method uses PCA to capture structures variability...
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ISBN:
(纸本)9781424406715;1424406714
We propose a 3D nonparametric, entropy-based, coupled, multishape approach for the segmentation of subcortical brain structures in magnetic resonance images (MRI). Our method uses PCA to capture structures variability. Because of complex relationships of pose and shape of the coupled structures, we only use their shape and size relation. To this end, we apply separate registrations of the structures. For each structure, we consider a similarity transform using seven parameters. In addition, to generate most accurate results, we estimate probability density functions (pdf) iteratively. The proposed method minimizes an entropy-based energy function using quasi-Newton algorithm. To improve the results, we use analytical derivatives. Sample results are given for the segmentation of putamen, thalamus and caudate illustrating the impact of coupling on the accuracy of the results.
The switched reluctance motor (SRM) and drive system is a candidate in various applications including the home appliance. The simple and low cost system with an adequate performance is also one topic to be developed. ...
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The switched reluctance motor (SRM) and drive system is a candidate in various applications including the home appliance. The simple and low cost system with an adequate performance is also one topic to be developed. A speed sensor directly increases the cost and it directly influences the reliability of the system. This paper proposes a simplified variable speed control system for the SRM without using an encoder. The method is not based on the exact rotor position estimation, only the turn off angle is determined from the simple relation between measured terminal voltage and current. The effectiveness of the proposed method is verified by the experimental result on the 3 kW 3-phase 6-stator-pole and 4-rotor-pole SRM.
We investigate two-way and one-way single-photon quantum key distribution (QKD) protocols in the presence of loss introduced by the quantum channel. Our analysis is based on a simple precondition for secure QKD in eac...
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We investigate two-way and one-way single-photon quantum key distribution (QKD) protocols in the presence of loss introduced by the quantum channel. Our analysis is based on a simple precondition for secure QKD in each case. In particular, the legitimate users need to prove that there exists no separable state (in the case of two-way QKD), or that there exists no quantum state having a symmetric extension (one-way QKD), that is compatible with the available measurements results. We show that both criteria can be formulated as a convex optimization problem known as a semidefinite program, which can be efficiently solved. Moreover, we prove that the solution to the dual optimization corresponds to the evaluation of an optimal witness operator that belongs to the minimal verification set of them for the given two-way (or one-way) QKD protocol. A positive expectation value of this optimal witness operator states that no secret key can be distilled from the available measurements results. We apply such analysis to several well-known single-photon QKD protocols under losses.
Design, simulation, and optimization of a novel (extremely) broad-band coplanar waveguide (CPW)-fed on-chip antenna using Genetic Algorithm (GA) will be presented. The antenna is of slot type and has the shape of a bo...
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Several path-planning algorithms for mobile robots have been introduced. Proper architectures for mobile robots to implement the path-planning algorithms are also of interest. If the mobile robots are to perform compl...
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In this paper, a new approach to enlarge the domain of attraction of a nonlinear affine system based on Zubov Theorem is suggested. The affine systems which are studied in this paper some times have some constraints t...
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Lack of sufficient flexibility to deal with actual noisy data in data fusion methods is the main concern in this paper. This deficiency comes from two major reasons. Firstly, infusion methods, all of the collected dat...
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We propose a hybrid model for simulations of hybrid systems and we establish conditions on its data so that the asymptotically stable sets observed in simulations are continuous. The most important components of the h...
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ISBN:
(纸本)1424401704;9781424401703
We propose a hybrid model for simulations of hybrid systems and we establish conditions on its data so that the asymptotically stable sets observed in simulations are continuous. The most important components of the hybrid model for simulations are a discrete integration scheme for the computation of the flows and an approximated jump mapping for the computation of the jumps. Our main result is built on the facts that, on compact hybrid time domains, every simulation to a hybrid system is arbitrarily close (in the graphical sense) to some solution to the actual hybrid system, and that asymptotically stable compact sets of hybrid systems are semiglobally practically asymptotically stable compact sets for the hybrid model for simulations. We present these results and illustrate them in simulations of the bouncing ball system
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