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Modeling and Control of Electrical Power and Energy Produced by a Synchronous Generator Using Polynomial Fuzzy Systems and Sum-Of-Squares Approach

The synchronous generator, as the main component of power systems, plays a key role in these system’s stability. Therefore, utilizing the most effective control strategy for modeling and control the synchronous generator results in the best outcomes in power systems’ performances. The advantage of using a powerful controller is to have the synchronous generator modeled and controlled as well as its main task i.e., stabilizing power systems. Since the synchronous generator is known as a complicated nonlinear system, modeling and control of it is a difficult task. This paper presents a sum of squares (SOS) approach to modeling and control the synchronous generator using polynomial fuzzy systems. This method as an efficacious control strategy has numerous superiorities to the well-known T-S fuzzy controller, due to the control framework is a polynomial fuzzy model, which is more general and effectual than the well-known T-S fuzzy model. In this case, a polynomial Lyapunov function is used for analyzing the stability of the polynomial fuzzy system. Then, the number of rules in a polynomial fuzzy model is less than in a T-S fuzzy model. Besides, derived stability conditions are represented in terms of the SOS approach, which can be numerically solved via the recently developed SOSTOOLS. This approach avoids the difficulty of solving LMI (Linear Matrix Inequality). The Effectiveness of the proposed control strategy is verified by using the third-part Matlab toolbox, SOSTOOLS.

Anomalous Conductance in Trans-Polyacetylene Chains with Even–Odd Parity

This work presents an analytical study of electronic transport in dimerized trans-polyacetylene (Trans PA) oligomers containing even (n = 4, 6, 8, 10 sites) and odd (n = 3, 5, 7, 9 sites) chains where the site C1 is sandwiched by two metallic electrodes (Left and Right). These devices exhibit T-shaped geometry and are investigated by Su-Schrieffer-Heeger (SSH) model via Heisenberg equation of motion combined with the Keldysh formalism. We introduced disorder into the system through the dimerization force (δ) demonstrating that the dimerization in the chain can effectively lead to a linear (low δ) or zigzag (high δ) behavior, besides also suffering increase or decrease in conductance peak [dI/dV]max. The odd chains exhibit trivial topological behavior to which the conductance peaks are suppressed as dimerization disorder is considered-creates barriers for tunneling. On the other hand, we have an opposite behavior for conductance peaks in the even chains. For example, the chain with weak dimerization (low δ) has a perfect transmission for even chains. In addition, we note for odd chains the formation of a plateau in the I–V curve for bias voltages and for even chains that show a linear current. This procedure shows an analytical study through the tunneling of the parameters on the device, such parameters as the tunneling amplitude (ГL/R) can be accessible experimentally.

An <i>In Silico</i> and <i>In Vitro</i> Study of the Metal Complex di-<i>μ</i>-Chloro-Bis[Chlorine (4,7-Dimethyl-1,10-Phenanthroline) Cadmium(ii)] with Antibacterial Potential

The bacteria are responsible for several diseases in humans and currently there is an increase in the development of resistance to commercial drugs. In this study, we evaluated In Vitro and in silico antibacterial potential of the metal complex di-μ-chloro-bis [chlorine (4, 7-dimethyl-1, 10-phenanthroline) cadmium (II)]. Computational techniques, DFT with hybrid functional and B3LYP/GEN base (LANL2DZ for Cd and 6–311++G** for C, N, Cl and H), were applied and compared with literature data. The In Vitro antibacterial biological assays revealed a halo of 16 mm and a minimum inhibitory concentration of 6.25 μg/cm3; for Enterococcus faecalis and Staphylococcus. aureus, respectively. Molecular docking simulations were realized and the complex presented satisfactory results of binding energy showing the ease with which the ligand binds to the E. faecalis (−8.14 kcal/mol) and S. aureus (−7.00 kcal/mol). Additionally, pharmacokinetic and toxicological predictions were realized. ADME/Tox profile results showed that, although the cadmium complex met several of the parameters required for potential drugs, it has not been classified as a suitable one due to its high molecular weight. The results obtained demonstrate the effectiveness of the cadmium complex as a potential antibacterial agent.