Instituto Tecnológico Superior de Irapuato

About: Instituto Tecnológico Superior de Irapuato is a education organization based out in Irapuato, Mexico. It is known for research contribution in the topics: AC power & Stability constants of complexes. The organization has 378 authors who have published 309 publications receiving 1171 citations. The organization is also known as: Instituto Tecnologico Superior de Irapuato & Higher Technological Institute of Irapuato.

A Single-Phase Asymmetrical T-Type Five-Level Transformerless PV Inverter

Abstract: This paper presents a transformerless single-phase inverter topology based on a modified H-bridge-based multilevel converter. The topology comprises two legs, namely, a usual two-level leg and a T-type leg. The latter is based on a usual two-level leg, which has been modified to gain access to the midpoint of the split dc-link by means of a bidirectional switch. The topology is referred as an asymmetrical T-type five-level (5L-T-AHB) inverter. An ad hoc modulation strategy based on sinusoidal pulsewidth modulation is also presented to control the 5L-T-AHB inverter, where the two-level leg is commuted at fundamental frequency. Numerical and experimental results show that the proposed 5L-T-AHB inverter achieves high efficiency, exhibits reduced leakage currents, and complies with the transformerless norms and regulations, which makes it suitable for the transformerless PV inverters market. 1 1 This updated version includes experimental evidence, considerations for practical implementation, efficiency studies, visualization of semiconductor losses distribution, a deeper and corrected common mode analysis, and an improved notation among other modifications.

Plant volatiles cause direct, induced and associational resistance in common bean to the fungal pathogen Colletotrichum lindemuthianum

Abstract: Summary Plants that express resistance to herbivores emit volatile organic compounds (VOCs) that can trigger resistance responses in undamaged neighbours. Recent reports indicate that VOCs can also trigger the resistance to pathogens, an effect that might be due to different mechanisms: the priming of an induced expression of resistance genes in the receiver or direct inhibitory effects on microbial pathogens that cause a passive ‘associational’ resistance in the VOC-exposed plant. We investigated whether VOCs emitted from a resistant common bean (Phaseolus vulgaris) cultivar enhance the resistance to the fungus Colletotrichum lindemuthianum in a susceptible cultivar and analysed whether specific VOCs are likely to directly affect the pathogen. We found that susceptible plants exposed to the headspace of resistance-expressing plants over 6 h became phenotypically as resistant as the resistant cultivar. Several resistance marker genes (PATHOGENESIS-RELATED [PR] 1, 2 and 4) were primed in VOC-exposed susceptible plants. After challenging, these genes reached expression levels at least as high as in the resistant cultivar. Additionally, individual VOCs such as limonene, linalool, nonanal, methyl salicylate and methyl jasmonate at natural concentrations directly inhibited the germination of conidia as did also the headspace of a resistance-expressing plant. This inhibition of conidial germination was dosage-dependent and irreversible. Synthesis. We conclude that VOCs are involved in the resistance of bean to fungal pathogens. They can contribute to the direct resistance in the emitter itself, and resistance phenotypes of neighbouring receiver plants can result from induced as well as associational resistance. Plant VOCs play multiple roles in the resistance of plants to microbial pathogens.

Homotopy perturbation transform method for nonlinear differential equations involving to fractional operator with exponential kernel

Abstract: This work presents the homotopy perturbation transform method for nonlinear fractional partial differential equations of the Caputo-Fabrizio fractional operator. Perturbative expansion polynomials are considered to obtain an infinite series solution. The effectiveness of this method is demonstrated by finding the exact solutions of the fractional equations proposed, for the special case when the limit of the integral order of the time derivative is considered.

The Feng’s first integral method applied to the nonlinear mKdV space-time fractional partial differential equation

Abstract: In this paper, the fractional derivatives in the sense of the modified Riemann-Liouville derivative and the Feng’s first integral method are employed for solving the important nonlinear coupled space-time fractional mKdV partial differential equation, this approach provides new exact solutions through establishing first integrals of the mKdV equation. The present method is efficient, reliable, and it can be used as an alternative to establish new solutions of different types of fractional differential equations applied in mathematical physics.

Electrical Properties of Two-Dimensional Materials Used in Gas Sensors.

Abstract: In the search for gas sensing materials, two-dimensional materials offer the possibility of designing sensors capable of tuning the electronic band structure by controlling their thickness, quantity of dopants, alloying between different materials, vertical stacking, and the presence of gases. Through materials engineering it is feasible to study the electrical properties of two-dimensional materials which are directly related to their crystalline structure, first Brillouin zone, and dispersion energy, the latter estimated through the tight-binding model. A review of the electrical properties directly related to the crystalline structure of these materials is made in this article for the two-dimensional materials used in the design of gas sensors. It was found that most 2D sensing materials have a hexagonal crystalline structure, although some materials have monoclinic, orthorhombic and triclinic structures. Through the simulation of the mathematical models of the dispersion energy, two-dimensional and three-dimensional electronic band structures were predicted for graphene, hexagonal boron nitride (h-BN) and silicene, which must be known before designing a gas sensor.