scholarly journals Evolutionary online behaviour learning and adaptation in real robots

2017 ◽  
Vol 4 (7) ◽  
pp. 160938 ◽  
Author(s):  
Fernando Silva ◽  
Luís Correia ◽  
Anders Lyhne Christensen
Keyword(s):  
Adaptive Capabilities ◽  
Task Requirements ◽  
Online Behaviour ◽  
Learning And Adaptation ◽  
Real Hardware ◽  
Robot Tasks ◽  
Behaviour Learning ◽  
First Time ◽  
Multiple Units ◽  
Algorithmic Component

Online evolution of behavioural control on real robots is an open-ended approach to autonomous learning and adaptation: robots have the potential to automatically learn new tasks and to adapt to changes in environmental conditions, or to failures in sensors and/or actuators. However, studies have so far almost exclusively been carried out in simulation because evolution in real hardware has required several days or weeks to produce capable robots. In this article, we successfully evolve neural network-based controllers in real robotic hardware to solve two single-robot tasks and one collective robotics task. Controllers are evolved either from random solutions or from solutions pre-evolved in simulation. In all cases, capable solutions are found in a timely manner (1 h or less). Results show that more accurate simulations may lead to higher-performing controllers, and that completing the optimization process in real robots is meaningful, even if solutions found in simulation differ from solutions in reality. We furthermore demonstrate for the first time the adaptive capabilities of online evolution in real robotic hardware, including robots able to overcome faults injected in the motors of multiple units simultaneously, and to modify their behaviour in response to changes in the task requirements. We conclude by assessing the contribution of each algorithmic component on the performance of the underlying evolutionary algorithm.

scholarly journals Adaptation of Orientation Vectors of Otolith-Related Central Vestibular Neurons to Gravity

2008 ◽  
Vol 100 (3) ◽  
pp. 1686-1690 ◽  
Author(s):  
Julia N. Eron ◽  
Bernard Cohen ◽  
Theodore Raphan ◽  
Sergei B. Yakushin
Keyword(s):  
Polarization Vector ◽  
Vestibular Nuclei ◽  
Perceptual Information ◽  
Behavioral Experiments ◽  
Adaptive Capabilities ◽  
Before And After ◽  
Vector Orientation ◽  
First Time ◽  
Specific Orientation ◽  
Response Vector

Behavioral experiments indicate that central pathways that process otolith-ocular and perceptual information have adaptive capabilities. Because polarization vectors of otolith afferents are directly related to the electro-mechanical properties of the hair cell bundle, it is unlikely that they change their direction of excitation. This indicates that the adaptation must take place in central pathways. Here we demonstrate for the first time that otolith polarization vectors of canal-otolith convergent neurons in the vestibular nuclei have adaptive capability. A total of 10 vestibular-only and vestibular-plus-saccade neurons were recorded extracellularly in two monkeys before and after they were in side-down positions for 2 h. The spatial characteristics of the otolith input were determined from the response vector orientation (RVO), which is the projection of the otolith polarization vector, onto the head horizontal plane. The RVOs had no specific orientation before animals were in side-down positions but moved toward the gravitational axis after the animals were tilted for extended periods. Vector reorientations varied from 0 to 109° and were linearly related to the original deviation of the RVOs from gravity in the position of adaptation. Such reorientation of central polarization vectors could provide the basis for changes in perception and eye movements related to prolonged head tilts relative to gravity or in microgravity.

The adaptive capacity of the female body after conducting medical abortion

2014 ◽  
Vol 20 (29) ◽  
pp. 0-0
Author(s):  
Алексеюк ◽  
Maksim Alekseyuk
Keyword(s):  
Menstrual Cycle ◽  
Adaptive Capacity ◽  
Female Body ◽  
Clinical Course ◽  
Medical Abortion ◽  
Second Phase ◽  
Vacuum Aspiration ◽  
Adaptive Capabilities ◽  
Manual Vacuum Aspiration ◽  
First Time

Based on the evaluation of the clinical course and the adaptive capabilities of the organism in the postabortion period after manual vacuum aspiration in 128 patients found that disorder of adaptation and the most frequent complications in the postabortion period observed in the production of abortion in the second phase of the suppositive menstrual cycle , especially in first time pregnant patients. In this way, the abortion in the first phase of "suppositive" menstrual cycle is the reserve for increasing the safety of abortion by MVA.

scholarly journals Problems of human relationships in the modern world

2021 ◽  
Vol 273 ◽  
pp. 10032
Author(s):  
Elena Pleshakova
Keyword(s):  
Empirical Study ◽  
Negative Attitude ◽  
Married Women ◽  
Modern World ◽  
Human Relationships ◽  
New Family ◽  
Adaptive Capabilities ◽  
First Time ◽  
The Relationship ◽  
Positive Factor

The article presents the results of an empirical study on changes in the system of a woman's relations after a divorce, which can be manifested both in a woman's self-attitude and in her attitude towards a man; divorced women, compared to married women, have a higher percentage of non-optimal self-attitude and negative attitude towards men, divorced women with and without a child after a divorce have got differences not only in the percentage of non-optimal self-attitude and negative attitude towards men, but also in the connection between them. We have conducted our research and received the following results. Divorced women, as compared to married women, have a higher percentage of suboptimal self-attitude and negative attitude towards men. The assumption that divorced women with a child after a divorce have got a higher percentage of non-optimal self-attitude and negative attitude towards a man than women without a child after a divorce was not confirmed, while the assumption of a less close connection of self-attitude and attitude towards a man was confirmed. For the first time, an empirical study was conducted that allows us to study not only the features of self-attitude and attitude to a man in women after divorce, but also the relationship between them. The results obtained in the study can be used by psychologists working with women who are divorced. The development of an optimal self-attitude in such women will not only increase adaptive capabilities, but also contribute to a change in attitude towards a man, which ultimately can be a positive factor in creating a new family.

scholarly journals Hepatoprotective and antioxidant effects of Mexidol-Vet® in an experiment on rats

2020 ◽  
Vol 2020 (5) ◽  
pp. 38-42
Author(s):  
Dmitriy Gildikov
Keyword(s):  
Toxic Hepatitis ◽  
Free Radical Oxidation ◽  
Antioxidant Effect ◽  
Male Rats ◽  
Histological Changes ◽  
Radical Oxidation ◽  
Blood Biochemical ◽  
Adaptive Capabilities ◽  
First Time ◽  
Sexually Mature

The aim of the work was to establish the hepatoprotective and antioxidant effect of Mexidol-Vet® in rats with toxic hepatitis. We have reproduced the toxic hepatitis in sexually mature male rats (n = 90) by a single intragastric injection of carbon tetrachloride. For 30 days, we studied reactivity, variations in blood biochemical parameters, the intensity of iron-induced chemiluminescence of homogenates and histological changes in the liver. The experiment confirmed the antioxidant effect and for the first time established the hepatoprotective effect of Mexidol-Vet®. The use of Mexidol-Vet® in rats with tetrachloromethane hepatitis increases reactivity and adaptive capabilities, correction of carbohydrate (lactate dehydrogenase) and protein metabolism (total protein, aspartate aminotransferase and alanine aminotransferase), inhibition of free radical oxidation and the development of oxidative stress.

Learning impedance control of antagonistic systems based on stochastic optimization principles

2010 ◽  
Vol 30 (5) ◽  
pp. 556-573 ◽  
Author(s):  
Djordje Mitrovic ◽  
Stefan Klanke ◽  
Sethu Vijayakumar
Keyword(s):  
Stochastic Optimization ◽  
First Principles ◽  
Impedance Control ◽  
Impedance Modulation ◽  
Noise Characteristics ◽  
Plant Dynamics ◽  
Real Hardware ◽  
Performance Gains ◽  
Stochastic Properties ◽  
First Time

Novel anthropomorphic robotic systems increasingly employ variable impedance actuation with a view to achieving robustness against uncertainty, superior agility and improved efficiency that are hallmarks of biological systems. Controlling and modulating impedance profiles such that they are optimally tuned to the controlled plant is crucial in realizing these benefits. In this work, we propose a methodology to generate optimal control commands for variable impedance actuators under a prescribed tradeoff of task accuracy and energy cost. We employ a supervised learning paradigm to acquire both the plant dynamics and its stochastic properties. This enables us to prescribe an optimal impedance and command profile (i) tuned to the hard-to-model plant noise characteristics and (ii) adaptable to systematic changes. To evaluate the scalability of our framework to real hardware, we designed and built a novel antagonistic series elastic actuator (SEA) characterized by a simple mechanical architecture and we ran several evaluations on a variety of reach and hold tasks. These results highlight, for the first time on real hardware, how impedance modulation profiles tuned to the plant dynamics emerge from the first principles of stochastic optimization, achieving clear performance gains over classical methods that ignore or are incapable of incorporating stochastic information.

scholarly journals Features of the reproduction processes of amphipods (Crustacea, Amphipoda) alien species in the conditions of Belarus watercourses

2019 ◽  
Vol 64 (1) ◽  
pp. 72-81 ◽  
Author(s):  
A. I. Makaranka
Keyword(s):  
Alien Species ◽  
Warm Season ◽  
Reproductive Period ◽  
Climatic Conditions ◽  
Age Composition ◽  
Adaptive Capabilities ◽  
Reproduction Period ◽  
Monthly Changes ◽  
Density And Biomass ◽  
First Time

For the first time in Belarus, reproduction features of 6 mass alien Amphipodae species have been established: C. curvispinum, D. villosus, O. crassus, O. obesus, E. ischnus, and D. haemobaphes. The data on the monthly changes in their density and biomass have been given, as well as the species these changes are most pronounced in. The range in temperature conditions, the reproduction processes are observed under, is determined. These conditions are mostly confined to the warm season: all species start reproduction in spring at a temperature of 7.9–11.9 °C and end it in autumn at a temperature of 9.7 °C. Based on changes in the age composition, the main parameters of the life cycle are determined. The reproduction period was established for 5 studied alien species, 2 to 3 generations were observed during a year, the sex ration is determined (the prevalence of females in the species represented indicates the populations stability). The obtained research results, in comparison with the literature data for other parts of the area with similar climatic conditions, mostly coincide, the differences are mainly determined by the temperature and environmental conditions of watercourses. Compared with populations from other parts of the species distribution that have a longer reproduction period, the same number of generations with a shorter reproductive period is observed in Belarus conditions for 5 species of Gammaridae, which indicates the wide adaptive capabilities of these species.

scholarly journals Brain Circuit for Cognitive Control Is Shared by Task and Language Switching

2015 ◽  
Vol 27 (9) ◽  
pp. 1752-1765 ◽  
Author(s):  
Wouter De Baene ◽  
Wouter Duyck ◽  
Marcel Brass ◽  
Manuel Carreiras
Keyword(s):  
Cognitive Control ◽  
Direct Evidence ◽  
Specific Activity ◽  
Task Requirements ◽  
Brain Circuit ◽  
Language Control ◽  
Switching Task ◽  
Functional Mechanisms ◽  
First Time ◽  
Multiple Languages

Controlling multiple languages during speech production is believed to rely on functional mechanisms that are (at least partly) shared with domain-general cognitive control in early, highly proficient bilinguals. Recent neuroimaging results have indeed suggested a certain degree of neural overlap between language control and nonverbal cognitive control in bilinguals. However, this evidence is only indirect. Direct evidence for neural overlap between language control and nonverbal cognitive control can only be provided if two prerequisites are met: Language control and nonverbal cognitive control should be compared within the same participants, and the task requirements of both conditions should be closely matched. To provide such direct evidence for the first time, we used fMRI to examine the overlap in brain activation between switch-specific activity in a linguistic switching task and a closely matched nonlinguistic switching task, within participants, in early, highly proficient Spanish–Basque bilinguals. The current findings provide direct evidence that, in these bilinguals, highly similar brain circuits are involved in language control and domain-general cognitive control.

Annulate lamellae in the Sertoli cells of guinea pig testis after unilateral torsion of the spermatic cord

1984 ◽  
Vol 42 ◽  
pp. 196-197
Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala
Keyword(s):  
Sertoli Cells ◽  
Guinea Pigs ◽  
Spermatic Cord ◽  
Present Report ◽  
Cell Types ◽  
Annulate Lamellae ◽  
Spermatogenic Cells ◽  
Electron Microscopic ◽  
Structural Details ◽  
First Time

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).

Electron spectroscopic imaging and diffraction

1991 ◽  
Vol 49 ◽  
pp. 706-707
Author(s):  
M. Rühle ◽  
J. Mayer ◽  
J.C.H. Spence ◽  
J. Bihr ◽  
W. Probst ◽  
...  
Keyword(s):  
Materials Science ◽  
Electron Spectroscopic Imaging ◽  
Magnetic Filter ◽  
Magnetic Imaging ◽  
Illumination System ◽  
Probe Size ◽  
Diffraction Patterns ◽  
Fritz Haber ◽  
Koehler Illumination ◽  
First Time

A new Zeiss TEM with an imaging Omega filter is a fully digitized, side-entry, 120 kV TEM/STEM instrument for materials science. The machine possesses an Omega magnetic imaging energy filter (see Fig. 1) placed between the third and fourth projector lens. Lanio designed the filter and a prototype was built at the Fritz-Haber-Institut in Berlin, Germany. The imaging magnetic filter allows energy-filtered images or diffraction patterns to be recorded without scanning using efficient area detection. The energy dispersion at the exit slit (Fig. 1) results in ∼ 1.5 μm/eV which allows imaging with energy windows of ≤ 10 eV. The smallest probe size of the microscope is 1.6 nm and the Koehler illumination system is used for the first time in a TEM. Serial recording of EELS spectra with a resolution < 1 eV is possible. The digital control allows X,Y,Z coordinates and tilt settings to be stored and later recalled.

A Novel TEM Technique for Characterizing As-Grown CVD Diamond Films

1991 ◽  
Vol 49 ◽  
pp. 956-957 ◽  
Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton
Keyword(s):  
Diamond Films ◽  
Chemical Vapor ◽  
Growth Direction ◽  
Dark Field ◽  
Growth Surface ◽  
Specimen Preparation ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
First Time ◽  
Microstructural Studies

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.

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