On global trajectory tracking control of robot manipulators with a delayed feedback

In this paper, the trajectory tracking control problem of a robot manipulator with cylindrical joints is considered by means of a nonlinear PD controller taking into account the delayed feedback structure. The conclusion about stability of a closed-loop system is obtained on the basis of the development of the direct Lyapunov method in the study of the stability property for a non-autonomous functional differential equation by constructing a Lyapunov functional with a semi-definite time derivative.

A computer program based on spectral analysis for speech correction in children

Insufficient development of speech and poor command of it interferes, in turn, with its perception by ear, even with the help of sound-amplifying equipment, complicates its understanding, comprehension and transmission of information in the process of communication, at least in an elementary form. Today, in different countries of the world, educational aids are being developed - devices and devices that provide children in need of this with filling the deficit of information about sounding speech, complementing the feedback structure by connecting visual perception. We have developed a computer program “Home speech therapists” to improve speech in children after cochlear implant.

MRAS-Based Switching Linear Feedback Strategy for Sensorless Speed Control of Induction Motor Drives

This paper presents a newly designed switching linear feedback structure of sliding mode control (SLF-SMC) plugged with an model reference adaptive system (MRAS) based sensorless field-oriented control (SFOC) for induction motor (IM). Indeed, the performance of the MRAS depends mainly on the operating point and the parametric variation of the IM. Hence, the sliding mode control (SMC) could be considered a good control alternative due to its easy implementation and robustness. Simulation and experimentation results are presented to show the superiority of the proposed SLF-SMC technique in comparison with the classical PI controller under different speed ranges and inertia conditions.

Evolution of a single-cell predictive model for packaging and budding of viruses based on TEM based measurements

Although detailed experimental investigations would provide insight into viral infections and vaccine production, building a computational framework is necessary to identify the parameters that regulate the budding and packaging of nucleocapsids. This study shows that a predictive model for the complete infection cycle can be built using nonlinear coupled ODEs and parameter estimation using a Genetic algorithm. Specifically, we have used a dataset containing the occluded virus information, budded virus in infected cells obtained by transmission electron microscopy (TEM). A novel parameter estimation strategy is proposed based on the k-medoid clustering of infected cells. Firstly, we show that the parameter estimation framework can be used for model evolution and selection of the feedback structure. Secondly, we show that the model was capable of capturing the distribution of packaged and unpackaged nucleocapsids in the nucleus, cytoplasm, and plasma membrane, the number of packaged and unpackaged ODV, and polyhedra in the nucleus. The proposed framework assumes importance in generating data for achieving quality by design in the optimization of vaccine/recombinant protein yield.

Comparison of Huelsmann Basic Biquad with View to the Decrease of the Attenuation over the Transient Frequency of the Operational Amplifier

The signal processing at discrete time requires an aliasing filter at the input and a reconstruction filter at its output. In this paper, selected basic structures of biquads are described and compared with a view to the decrease of the attenuation over the transient frequency of the operational amplifier. Concretely, low-pass and band-pass Huelsman (i.e. multi feedback) structure are confronted with the limits of a real operational amplifier. Firstly, the reasons of the decreasing of the attenuation are explained theoretically. Secondly, these conclusions are verified by simulations. These simulations were performed by spice-like circuit simulator MicroCap version 10.