Síntesis de interpolación de los controladores para un sistema de accionamiento eléctrico multimotor que contiene un elemento enlazado elásticamente

Partial differential equations, integral, differential, or other equations describe multi-motor automatic electric drive systems containing elastic conveyor belts. Because of the elastic and distributive nature of the system parameters, the transfer function describing them is often a complex expression, containing not only the arguments as a linear system but also the inertial and transcendental components. This makes the precise control of tension and speed synchronously much more complicated than the centralized parameter system. A promising numerical solution based on the real interpolation method will simplify the procedure for synthesizing control loops while preserving the characteristic properties of objects with distributed parameters. The objective of the study is to propose a feasible solution for synthesizing the regulators based on the real interpolation method; it allows direct operation with the original transfer function containing the inertial and transcendental components. In this paper, we proposed an approach to synthesize the control system for objects with distributed parameters using the real interpolation method to reduce computational capacity and synthesis error while preserving the properties of this object class. Building an experimental model of the two-motor electric drive system containing an elastic conveyor to verify the effectiveness of the proposed algorithm. The simulation and experimental results indicate that the control system with the received regulators operating stably and meets the required quality criteria. It proves the efficiency of the synthesis algorithm based on the real interpolation method.Introducción: los sistemas de accionamiento eléctrico multimotor que incluyen transportadores elásticos son un ejemplo de sistemas típicos con parámetros distribuidos descritos por ecuaciones complejas. Debido a la naturaleza elástica y distributiva de los parámetros del sistema, la función de transferencia que los describe suele ser una expresión compleja que contiene los componentes inercial y trascendental. Problema: la naturaleza elástica y distributiva de los parámetros del sistema hace que el control preciso de la tensión y la velocidad sincrónicamente sea mucho más complicado que el sistema de parámetros centralizados. Metodología: se propone una solución numérica para sintetizar los reguladores basada en el método de interpolación real para reducir la capacidad computacional y el error de síntesis preservando las propiedades características de los objetos con parámetros distribuidos. Conclusión: la eficacia del algoritmo propuesto se verifica mediante un modelo experimental del sistema de accionamiento eléctrico de dos motores que contiene un transportador elástico. Los resultados de simulación y experimentales indican que el sistema de control con los reguladores recibidos opera de manera estable y cumple con los criterios de calidad requeridos. Originalidad: los resultados de la investigación se pueden aplicar en el desarrollo de sistemas centrales de control y monitoreo para líneas de producción automáticas con sistemas de accionamiento multimotor que incluyen transportadores

Curie Temperature of Diluted Magnetic Semiconductors: the Influence of the Antiferromagnetic Exchange Interaction

The coherent potential approximation and mean field approximation are used to calculate the free energy of the coupled carrier – localized spin system in III-V diluted magnetic semiconductors. Thus the magnetic transition temperature Tc can be determined and its dependence on important model parameters. We show that the strong antiferromagnetic superexchange interaction between nearest neighbour sites considerably reduces the Curie temperature

Composition of animal manure and co-products

224pThis study was conducted to determine the real outflow of liquid effluents to be considered in balance calculations at the farm and regional levels in Vietnamese conditions. The variability of the chemical composition of a local dataset was analysed considering the highly heterogeneous wastes and byproducts used on crops. Near infrared spectroscopy (NIRS) was introduced to evaluate the feasibility of a rapid technique applied to animal wastes. Characterization of effluent outflows and water use and composition variation of solid co-products (compost and fish food) was carried out. Quantity of animal solid waste per pig head in the cold seasons was higher than in the hot season. Data collected from ten farms in Thai Binh (Vietnam), showed that the content of the main constituents in the fresh weight (FW) in the warm season was 17.3% OM total. Nitrogen, P2O5 and K2O totals were 160, 3.51 and 0.59%, respectively. Raising pigs in the cold season discharged 0.352kg N, 0.229 kg P2O5 and 0.148 kg K2O per metric ton live weight and he liquid part contributed 5.5, 2.1 and 12.8%, respectively. A total of 66 samples of compost and animal waste as fish feed were taken during summer, of which 46 were ready-to-spread compost, 20 others were animal excreta as fish feed. These results confirmed the fact that it is possible to use the animal waste source coming from the pig farms of Thai Binh province as a main nutrient for crops, especially for rice. After preliminary calibrations using NIRS spectrometry with local pig waste and co-products, perspectives are promising in terms of research and local development. A description of the design of the Chinese digester, more commonly called biogas digester and of the NIRS technique is provided

The influences of the number of concrete dowels to shear resistance based on push out tests

To reduce the depth of floor-beam structures and to save the cost of headed-shear studs, many types of shallow composite beam have been developed during the last few years. Among them, the shallow-hollow steel beam consists of web openings, infilled with in-situ concrete (named concrete dowel) has been increasingly focused recently. In this new kind of structure, this concrete dowel plays an important role as the principal shear connector. This article presents an investigation on the shear transferring mechanism and failure behavior of the trapezoid shape concrete dowel. An experimental campaign of static push-out tests has been conducted with variability in the number of web openings (WOs). The results indicate that the mechanical behavior of concrete dowel could be divided into crushing, compression, and tension zones and exhibits brittle behavior. The longitudinal shear resistance and specimen's stiffness are strongly affected by the number of considered WO