Generalized model of interacting dark energy and dark matter: Phase portrait analysis for evolving universe

The main aim of this work is to give a suitable explanation of present accelerating universe through an acceptable interactive dynamical cosmological model. A three-fluid cosmological model is introduced in the background of Friedmann–Lemaître–Robertson-Walker asymptotically flat spacetime. This model consists of interactive dark matter and dark energy with baryonic matter, taken as perfect fluid, satisfying barotropic equation of state. We consider dust as the candidate of dark matter. A scalar field [Formula: see text] represents dark energy with potential [Formula: see text]. Einstein’s field equations are utilized to construct a three-dimensional interactive autonomous system by choosing suitable interaction between dark energy and dark matter. We take the interaction kernel as [Formula: see text], where [Formula: see text] indicates the density of dark energy, [Formula: see text] is the interacting constant and [Formula: see text] is Hubble parameter. In order to explain the stability of this system, we obtain some suitable critical points. We analyze stability of obtained critical points to show the different phases of universe and cosmological implications. Surprisingly, we find some stable critical points which represent late-time dark energy-dominated era when a model parameter [Formula: see text] is equal to [Formula: see text]. We introduce a two-dimensional interactive autonomous system and after phase portrait analysis of it, we get several stable points which represent dark energy-dominated era and late-time cosmic acceleration simultaneously. Here, we also demonstrate the variation in interaction at vicinity of phantom barrier [Formula: see text]. From our work, we can also predict the future phase evolution of the universe.

Воздействие гармонического сигнала на генератор квазипериодических колебаний Анищенко-Астахова

A harmonic effect on a modified Anishchenko-Astakhov generator capable of demonstrating two-frequency quasi-periodic oscillations in the autonomous mode is considered. The possibility of doubling the three-frequency tori in a non-autonomous system is shown. The possibility of the effect of chaos suppression by an external signal is demonstrated, which leads not only to periodic, but also to quasi-periodic modes when the influence amplitude exceeds a certain threshold.

PHOTOVOLTAIC PUMPING: ALTERNATIVE FOR MICROIRRIGATION IN THE MATA MINEIRA AREA

The objective of the research was to evaluate the uniformity of drip irrigation with photovoltaic pumping with and without storage in batteries. using normal and self-compensating emitters. The experiment was conducted at the Federal University of Viçosa. Minas Gerais. Brazil. Two drip irrigation systems were tested. one with self-compensating emitters and the other with normal emitters with a flow rate of 4 L h-1. The coefficients of uniformity of Cristiansen and distribution (CUC and CUD) were used to evaluate the performance of the irrigation systems. The volumes pumped by the autonomous system and stored in batteries throughout the year in all regions of the country were compared for the period from 02/01/2018 to 01/31/2019. a period that contemplates the data collection phase of the experiment. According to the results. the uniformity of the drip systems with and without energy storage. with emitters normal and self-compensating presented a coefficient between 93% and 97%. classified as excellent. The largest volumes pumped throughout the year for drip irrigation systems with normal and self-compensating emitters without batteries occurred in the Northeast region of Brazil.

Autonomous UAV System for Cleaning Insulators in Power Line Inspection and Maintenance

The inspection and maintenance tasks of electrical installations are very demanding. Nowadays, insulator cleaning is carried out manually by operators using scaffolds, ropes, or even helicopters. However, these operations involve potential risks for humans and the electrical structure. The use of Unmanned Aerial Vehicles (UAV) to reduce the risk of these tasks is rising. This paper presents an UAV to autonomously clean insulators on power lines. First, an insulator detection and tracking algorithm has been implemented to control the UAV in operation. Second, a cleaning tool has been designed consisting of a pump, a tank, and an arm to direct the flow of cleaning liquid. Third, a vision system has been developed that is capable of detecting soiled areas using a semantic segmentation neuronal network, calculating the trajectory for cleaning in the image plane, and generating arm trajectories to efficiently clean the insulator. Fourth, an autonomous system has been developed to land on a charging pad to charge the batteries and potentially fill the tank with cleaning liquid. Finally, the autonomous system has been validated in a controlled outdoor environment.

Neuroprotective role of human neuritin 1 on axotomized human eyes pressurized using the Translaminar Autonomous System

Purpose: Primary open-angle glaucoma is a leading cause of vision loss worldwide characterized by retinal ganglion cell death (RGC) and visual field loss. Glaucoma is most commonly associated with an increase in intraocular pressure (IOP), and current clinical management is limited to lowering intraocular pressure. We have previously shown that the secreted human protein neuritin 1 (NRN1) exhibits neuroprotection, regeneration, and preservation of RGC function after RGC axonal injury. We propose to overcome RGC degeneration by over-expressing NRN1 in our novel ex-vivo perfused pressurized Translaminar Autonomous System (TAS). Methods: Human donor eyes were obtained from eye banks. To model glaucomatous conditions, dissected human posterior eye cups were cultured in the TAS model with IOP:ICP conditions of 16:12 mmHg over 6 days. Flow rate of perfusion medium to the interior and exterior (around optic nerve) of the eye cup (IOP and ICP, respectively) was controlled by automated pumps to induce the translaminar pressure gradient.We assessed survival of RGCs with and without hNRN1 treatment by TaqMan array analysis of apoptosis/inflammatory markers (retina). Expression of FN and COLIV was examined from conditioned medium of both groups by Western analysis. Results: We successfully maintained IOP: ICP differentials over 6 days. The RGCs degenerated faster in non-treated conditions compared to NRN1 treated eyes. In contrast to control, NRN1-treated group displayed differential expression of FN and COLIV. We observed dysregulated expression of GFAP, BAX and TLR4 expression between control and experimental conditions. Conclusion: We utilized our unique TAS model to recreate the human optic nerve head environment of elevated translaminar pressure for testing a unique neuroprotective and regenerative gene therapy. Using this approach, we hope to identify human Neuritin 1 as a therapeutic gene to save the visual neurons and develop a new treatment for glaucoma.

Mechanism, autonomy and biological explanation

The new mechanists and the autonomy approach both aim to account for how biological phenomena are explained. One identifies appeals to how components of a mechanism are organized so that their activities produce a phenomenon. The other directs attention towards the whole organism and focuses on how it achieves self-maintenance. This paper discusses challenges each confronts and how each could benefit from collaboration with the other: the new mechanistic framework can gain by taking into account what happens outside individual mechanisms, while the autonomy approach can ground itself in biological research into how the actual components constituting an autonomous system interact and contribute in different ways to realize and maintain the system. To press the case that these two traditions should be constructively integrated we describe how three recent developments in the autonomy tradition together provide a bridge between the two traditions: (1) a framework of work and constraints, (2) a conception of function grounded in the organization of an autonomous system, and (3) a focus on control.

MIDAS: Multi-sensorial Immersive Dynamic Autonomous System Improves Motivation of Stroke Affected Patients for Hand Rehabilitation

In this paper, we present the design and development of MIDAS. MIDAS is intended to be a portable immersive system inclusive of an exoskeleton, a smell releasing device, and a VR game that will help stroke patients feel more motivated during a hand rehabilitation session. MIDAS engages four out of five senses during rehabilitation. MIDAS uses EMG signals taken from the subject’s forearm to predict their intention before activating physical assistance (tactile) in the opening or closing of the fingers of their hand. To evaluate the performance of MIDAS, a pilot study is done using established tools to quantify the user experience, comfort, pleasure, and motivation of the subjects in using MIDAS for rehabilitation exercises.<br>

MIDAS: Multi-sensorial Immersive Dynamic Autonomous System Improves Motivation of Stroke Affected Patients for Hand Rehabilitation

In this paper, we present the design and development of MIDAS. MIDAS is intended to be a portable immersive system inclusive of an exoskeleton, a smell releasing device, and a VR game that will help stroke patients feel more motivated during a hand rehabilitation session. MIDAS engages four out of five senses during rehabilitation. MIDAS uses EMG signals taken from the subject’s forearm to predict their intention before activating physical assistance (tactile) in the opening or closing of the fingers of their hand. To evaluate the performance of MIDAS, a pilot study is done using established tools to quantify the user experience, comfort, pleasure, and motivation of the subjects in using MIDAS for rehabilitation exercises.<br>

The dynamics of synchronization of two-stage van der Pol generator

Results of numerical simulation of self-oscillations synchronization process in two-cascade ring generator van der Pol by harmonic signal are presented. Studies were carried out within the framework of the DT- model of the dynamic system. The model was developed on the basis of the principle of compliance within the framework of the method of slowly changing amplitudes of characteristics of a discrete system with characteristics of an analog prototype. Shortened equations for complex oscillation amplitudes in generator stages are obtained. It was found that in an autonomous system there is an effect of bistability of amplitudes. In the synchronization mode with an external harmonic signal, solutions of shortened equations made it possible to calculate amplitude-frequency and phase-frequency characteristics of synchronous oscillations. It is shown that transitions between bistable states are observed in the synchronous oscillation holding band. Differences of frequency characteristics of synchronization of classical and two-stage oscillators van der Pol were analyzed.