This paper presents a variable structure control method for a single stage three level resonant AC/DC converter. An observer with adaptive parameter estimation is also introduced to achieve current sensorless operatio...
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This paper presents a variable structure control method for a single stage three level resonant AC/DC converter. An observer with adaptive parameter estimation is also introduced to achieve current sensorless operation of the controller, thus returning the number of feedback measurements to two (both of which are voltage measurements) instead of three. Two switching functions are used: one to regulate the output voltage and the other switching function is to regulate both the input current and dc-bus voltage. This controller also makes the system response less sensitive to load variations, supply voltage changes and resonant tank parameter variations.
We consider sequential hypothesis testing between two quantum states using adaptive and non-adaptive strategies. In this setting, samples of an unknown state are requested sequentially and a decision to either continu...
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A metapopulation structure in landscape ecology comprises a group of interacting spatially separated subpopulations or patches of the same species that may experience several local extinctions. This makes the investig...
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A metapopulation structure in landscape ecology comprises a group of interacting spatially separated subpopulations or patches of the same species that may experience several local extinctions. This makes the investigation of survivability (in the form of global oscillation) of a metapopulation on top of diverse dispersal topologies extremely crucial. However, among various dispersal topologies in ecological networks, which one can provide higher metapopulation survivability under local extinction is still not well explored. In this article, we scrutinize the robustness of an ecological network consisting of prey-predator patches having Holling type I functional response, against progressively extinct population patches. We present a comprehensive study on this while considering global, small-world, and scale-free dispersal of the subpopulations. Furthermore, we extend our work in enhancing survivability in the form of sustained global oscillation by introducing asymmetries in the dispersal rates of the considered species. Our findings affirm that the asynchrony among the patches plays an important role in the survivability of a metapopulation. In order to demonstrate the model independence of the observed phenomenon, we perform a similar analysis for patches exhibiting Holling type II functional response. On the grounds of the obtained results, our work is expected to provide a better perception of the influence of dispersal arrangements on the global survivability of ecological networks.
This paper presents a state space modelling approach for a single stage three level resonant power factor correction converter operating with variable frequency phase shift control in discontinuous conduction mode. Mo...
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This paper presents a state space modelling approach for a single stage three level resonant power factor correction converter operating with variable frequency phase shift control in discontinuous conduction mode. Modelling is achieved using a combined averaging and multiple-frequency approach. The model gives good prediction of both the transient and steady state operations of the converter. The dynamics of the output filter can also be represented as well as the influence of parasitic parameters such as the capacitor equivalent series resistance (ESR). This method also allows the separation of both the frequency and duty cycle as the control variables. All state variables are broken down into their frequency components, including high and low frequency components (the high frequency components being in the order of the switching frequency and the low frequency components being in the order of power line frequency) and the amplitudes of the frequency components are used as the new state variables. As a result a model is obtained that has the switching frequency as well as the required duty ratio for the phase-shift-modulation as separated control input variables, which facilitates controller design. The developed model is verified on a 2.3 kW, 48 V, input voltage 90-265 V rms .
In this paper we study hyperstructure generalizations of lattices. We give conditions for EL-semihypergroups to be Hv-semilattices, hypersemilattices or hyperlattices. We also study some of their special elements.
ISBN:
(纸本)9788022746502
In this paper we study hyperstructure generalizations of lattices. We give conditions for EL-semihypergroups to be Hv-semilattices, hypersemilattices or hyperlattices. We also study some of their special elements.
The great breakthrough in technological devices has lead to the migration of actual Internet to the Internet of Things. There are merely trillions of smart dynamic objects that will be connected to the Internet and th...
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The great breakthrough in technological devices has lead to the migration of actual Internet to the Internet of Things. There are merely trillions of smart dynamic objects that will be connected to the Internet and that interact and collaborate together independently from any physical location. This progress necessitates the proposal of an adequate architecture and routing process. In this paper, we propose a novel design and overlay architecture that fulfills the Internet of Things requirements. This approach is mainly based on Distributed Hash Table protocols to afford the required flexiblity and to handle efficiently mobility and churn cases. We present also a formal study that proves the efficiency of our proposed architecture.
Automatic detection and identification of seismic events is an important task that is carried out constantly for seismic monitoring. This monitoring process results in a seismic event bulletin that contains informatio...
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The paper deals with the numerical solution of elliptic boundary value problems for 2D linear elasticity using the fictitious domain method in combination with the discrete Fourier transform and the FETI domain decomp...
The paper deals with the numerical solution of elliptic boundary value problems for 2D linear elasticity using the fictitious domain method in combination with the discrete Fourier transform and the FETI domain decomposition. We briefly mention the theoretical background of these methods, introduce resulting solvers, and demonstrate their efficiency on model benchmarks.
Model predictive control (MPC) is an industry standard control technique that iteratively solves an open-loop optimization problem to guide a system towards a desired state or trajectory. Consequently, an accurate for...
This study addresses the dynamic spectrum access problem in a wireless sub-network that shares channels with a parent network. We approach the sequential channel allocation problem using a restless multi-armed bandits...
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