Search results for "Cybernetics"

Информационные свойства сотообразных структур

1972

The 2020 magnetism roadmap

2020

Following the success and relevance of the 2014 and 2017 Magnetism Roadmap articles, this 2020 Magnetism Roadmap edition takes yet another timely look at newly relevant and highly active areas in magnetism research. The overall layout of this article is unchanged, given that it has proved the most appropriate way to convey the most relevant aspects of today's magnetism research in a wide variety of sub-fields to a broad readership. A different group of experts has again been selected for this article, representing both the breadth of new research areas, and the desire to incorporate different voices and viewpoints. The latter is especially relevant for thistype of article, in which one's fi…

Adaptive dual control in one biomedical problem

2003

In this paper, the following biomedical problem is considered. People are subjected to a certain chemotherapeutic treatment. The optimal dosage is the maximal dose for which an individual patient will have toxicity level that does not cross the allowable limit. We discuss sequential procedures for searching the optimal dosage, which are based on the concept of dual control and the principle of optimality. According to the dual control theory, the control has two purposes that might be conflicting: one is to help learning about unknown parameters and/or the state of the system (estimation); the other is to achieve the control objective. Thus the resulting control sequence exhibits the closed…

Surrogate data analysis of sleep electroencephalograms reveals evidence for nonlinearity

1996

We tested the hypothesis of whether sleep electroencephalographic (EEG) signals of different time windows (164 s, 82 s, 41 s and 20.5 s) are in accordance with linear stochastic models. For this purpose we analyzed the all-night sleep electroencephalogram of a healthy subject and corresponding Gaussian-rescaled phase randomized surrogates with a battery of five non-linear measures. The following nonlinear measures were implemented: largest Lyapunov exponent L1, correlation dimension D2, and the Green-Savit measures delta 2, delta 4 and delta 6. The hypothesis of linear stochastic data was rejected with high statistical significance. L1 and D2 yielded the most pronounced effects, while the G…

Deterministic chaos and the first positive Lyapunov exponent: a nonlinear analysis of the human electroencephalogram during sleep

1993

Under selected conditions, nonlinear dynamical systems, which can be described by deterministic models, are able to generate so-called deterministic chaos. In this case the dynamics show a sensitive dependence on initial conditions, which means that different states of a system, being arbitrarily close initially, will become macroscopically separated for sufficiently long times. In this sense, the unpredictability of the EEG might be a basic phenomenon of its chaotic character. Recent investigations of the dimensionality of EEG attractors in phase space have led to the assumption that the EEG can be regarded as a deterministic process which should not be mistaken for simple noise. The calcu…

From "Non-encounters" to autonomic agency. Conceptions of patients with low back pain about their encounters in the health care system.

2018

Low back pain is a considerable health problem which affects people around the world, causing major healthcare costs. The use of qualitative research methods enables us to describe and understand patients' experience of, and attitudes to, healthcare. The aim of the present phenomenographic study was to identify and describe the contextual nature of the conceptions of patients with low back pain of their encounters in the HCS. Seventeen patients with chronic or episodic low back pain classified as "high risk" were interviewed in open recall interviews, using videos of patients' initial physiotherapy sessions that had been recorded previously. The data were analysed using the phenomenographic…

Towards the Preservation and Dissemination of Historical Silk Weaving Techniques in the Digital Era

2019

Historical weaving techniques have evolved in time and space giving as result more or less fabrics with different aesthetical characteristics. These techniques were transferred along the main silk production centers, thanks to the European Silk Road and creating a common European Frame on themes and techniques. These had made it complicated to determine whether a fabric corresponds to one century or another. Moreover, in order to understand their creation, it is necessary to determine the number of weaves and interlacements that each textile has, therefore, mathematical models can be extracted from these layers. In this sense, three dimensional (3D) virtual representations of the internal s…

Design and implementation of an augmented reality application for rock art visualization in Cova dels Cavalls (Spain)

2019

[EN] Prehistoric rock art paintings, specifically rock-shelters exposed to environmental and anthropogenic factors, are usually faint and severely damaged, being them difficult to identify and understand by visitors. Augmented Reality (AR) supplements reality with virtual information superimposed onto the real world. This sensor-based technology in smartphones/tablets can improve the paintings experience displaying the 2D digital tracings overlapped onto the real scene (rock with faint paintings). This paper presents an AR application (app) developed in Cova dels Cavalls that shows a recreation of a possible original composition full of motifs with descriptive information to improve current…

BIM Modelling of Ancient Buildings

2018

In the last years, new procedures on design and management of constructions, based on 3D standardised models of building elements, have been proposed. It’s the case of Building Information Modelling (BIM) applications, that, differently from CAD ones, allow to work with libraries of 3D parametrical objects (smart objects) describing geometric, structural and material properties of building elements. This methodology is based on the Industry Foundation Classes (IFC) model, that represents a global standard for the building data exchange. Initially used for the design of new architectures, BIM methodology has been even more considered also for the management and the conservation of historical…

Safer chemicals using less animals: kick-off of the European ONTOX project

2021

The 3Rs concept, calling for replacement, reduction and refinement of animal experimentation, is receiving increasing attention around the world, and has found its way to legislation, in particular in the European Union. This is aligned by continuing high-level efforts of the European Commission to support development and implementation of 3Rs methods. In this respect, the European project called "ONTOX: ontology-driven and artificial intelligence-based repeated dose toxicity testing of chemicals for next generation risk assessment" was recently initiated with the goal to provide a functional and sustainable solution for advancing human risk assessment of chemicals without the use of animal…