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1.
Sensors (Basel) ; 21(21)2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34770577

ABSTRACT

An algorithm designed for analysis and understanding a 3D urban-type environment by an autonomous flying agent, equipped only with a monocular vision, is presented. The algorithm is hierarchical and is based on the structural representation of the analyzed scene. Firstly, the robot observes the scene from a high altitude to build a 2D representation of a single object and a graph representation of the 2D scene. The 3D representation of each object arises as a consequence of the robot's actions, as a result of which it projects the object's solid on different planes. The robot assigns the obtained representations to the corresponding vertex of the created graph. The algorithm was tested by using the embodied robot operating on the real scene. The tests showed that the robot equipped with the algorithm was able not only to localize the predefined object, but also to perform safe, collision-free maneuvers close to the structures in the scene.


Subject(s)
Algorithms , Vision, Monocular
2.
Sensors (Basel) ; 21(11)2021 Jun 07.
Article in English | MEDLINE | ID: mdl-34200416

ABSTRACT

Strawberry fruits are products of high commercial and consumption value, and, at the same time, they are difficult to harvest due to their very low mechanical strength and difficulties in identifying them within the bush. Therefore, robots collecting strawberries should be equipped with four subsystems: a video object detection system, a collecting arm, a unit for the reception and possible packaging of the fruit, and a traction system unit. This paper presents a concept for the design and operation of the working section of a harvester for strawberry fruit crops grown in rows or beds, in open fields, and/or under cover. In principle, the working section of the combine should meet parameters comparable with those of manually harvested strawberries (efficiency, quality of harvested fruit) and minimise contamination in the harvested product. In order to meet these requirements, in the presented design concept, it was assumed that these activities would be performed during harvesting with the natural distribution of fruits within the strawberry bush, and the operation of the working head arm maneuvering in the vicinity of the picked fruit, the fruit receiving unit, and other obstacles was developed on the basis of image analysis, initially general, and in detail in the final phase. The paper also discusses the idea of a vision system in which the algorithm used has been positively tested to identify the shapes of objects, and due to the similarity of space, it can be successfully used for the correct location of strawberry fruit.


Subject(s)
Fragaria , Robotics , Agriculture , Crops, Agricultural , Fruit
3.
Entropy (Basel) ; 22(2)2020 Feb 16.
Article in English | MEDLINE | ID: mdl-33285994

ABSTRACT

An investigation of diseases using magnetic resonance (MR) imaging requires automatic image quality assessment methods able to exclude low-quality scans. Such methods can be also employed for an optimization of parameters of imaging systems or evaluation of image processing algorithms. Therefore, in this paper, a novel blind image quality assessment (BIQA) method for the evaluation of MR images is introduced. It is observed that the result of filtering using non-maximum suppression (NMS) strongly depends on the perceptual quality of an input image. Hence, in the method, the image is first processed by the NMS with various levels of acceptable local intensity difference. Then, the quality is efficiently expressed by the entropy of a sequence of extrema numbers obtained with the thresholded NMS. The proposed BIQA approach is compared with ten state-of-the-art techniques on a dataset containing MR images and subjective scores provided by 31 experienced radiologists. The Pearson, Spearman, Kendall correlation coefficients and root mean square error for the method assessing images in the dataset were 0.6741, 0.3540, 0.2428, and 0.5375, respectively. The extensive experimental evaluation of the BIQA methods reveals that the introduced measure outperforms related techniques by a large margin as it correlates better with human scores.

4.
Environ Sci Pollut Res Int ; 27(11): 11506-11530, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32103433

ABSTRACT

In this paper, we present a comparative review of the externalities of electricity production. First of all, the environmental impact is considered. A discussion of the influence of various electricity production processes on human health follows. The studies are conducted in the context of historical development. Current trends, as well as a historical background that resulted in the changes that can be observed today, are presented. The considerations are supported by a few case studies. Analysis of perspectives for the development of electricity generation methods, in particular the indication of clean energy sources and the perspectives of their exploitation, is the main aim of this paper.


Subject(s)
Electricity , Energy-Generating Resources , Environment , Humans , Renewable Energy
5.
Med Health Care Philos ; 20(1): 23-35, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27491808

ABSTRACT

The studies of health care systems are conducted intensively on various levels. They are important because the systems suffer from numerous pathologies. The health care is analyzed, first of all, in economic aspects but their functionality in the framework of systems theory is studied, as well. There are also attempts to work out some general values on which health care systems should be based. Nevertheless, the aforementioned studies, however, are fragmentary ones. In this paper holistic approach to the philosophical basis of health care is presented. The levels on which the problem can be considered are specified explicitly and relations between them are analyzed, as well. The philosophical basis on which the national health care systems could be based is proposed. Personalism is the basis for the proposal. First of all, the values, that are derived from the personalistic philosophy, are specified as the basic ones for health care systems. Then, general organizational and functional properties of the system are derived from the assumed values. The possibility of adaptation of solutions from other fields of social experiences are also mentioned. The existing health care systems are analyzed within the frame of the introduced proposal.


Subject(s)
Delivery of Health Care , Philosophy, Medical , Delivery of Health Care/economics , Delivery of Health Care/organization & administration , Humans , Models, Theoretical , National Health Programs/economics , National Health Programs/organization & administration , Personhood
6.
Biol Cybern ; 109(3): 401-19, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25985758

ABSTRACT

Life, not only in the well-known context of biochemical metabolism but also in the context of hypothetical life synthesized laboratorially or possibly found on other planets, is considered in this paper. The three-component information-energetic-structural irreducible processing in autonomous systems is the core of the proposed approach. The cybernetic organization of a general entity of life--the alivon--is postulated. The crucial properties of life and evolution are derived from the proposed approach. Information encoded in biological structures is also studied.


Subject(s)
Biological Evolution , Cybernetics , Models, Biological , Humans , Origin of Life
7.
Biol Cybern ; 102(6): 489-502, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20407909

ABSTRACT

Neurotransmitters in the terminal bouton of a presynaptic neuron are stored in vesicles, which diffuse in the cytoplasm and, after a stimulation signal is received, fuse with the membrane and release its contents into the synaptic cleft. It is commonly assumed that vesicles belong to three pools whose content is gradually exploited during the stimulation. This article presents a model that relies on the assumption that the release ability is associated with the vesicle location in the bouton. As a modeling tool, partial differential equations are chosen as they allow one to express the continuous dependence of the unknown vesicle concentration on both the time and space variables. The model represents the synthesis, concentration-gradient-driven diffusion, and accumulation of vesicles as well as the release of neuroactive substances into the cleft. An initial and boundary value problem is numerically solved using the finite element method (FEM) and the simulation results are presented and discussed. Simulations were run for various assumptions concerning the parameters that govern the synthesis and diffusion processes. The obtained results are shown to be consistent with those obtained for a compartment model based on ordinary differential equations. Such studies can be helpful in gaining a deeper understanding of synaptic processes including physiological pathologies. Furthermore, such mathematical models can be useful for estimating the biological parameters that are included in a model and are hard or impossible to measure directly.


Subject(s)
Axons/metabolism , Computer Simulation , Neurons/metabolism , Neurotransmitter Agents/metabolism , Presynaptic Terminals/metabolism , Biological Transport , Finite Element Analysis
8.
Biol Cybern ; 99(6): 443-58, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18807067

ABSTRACT

In this paper a mathematical description of a presynaptic episode of slow synaptic neuropeptide transport is proposed. Two interrelated mathematical models, one based on a system of reaction diffusion partial differential equations and another one, a compartment type, based on a system of ordinary differential equations (ODE) are formulated. Processes of inflow, calcium triggered activation, diffusion and release of neuropeptide from large dense core vesicles (LDCV) as well as inflow and diffusion of ionic calcium are represented. The models assume the space constraints on the motion of inactive LDCVs and free diffusion of activated ones and ions of calcium. Numerical simulations for the ODE model are presented as well. Additionally, an electronic circuit, reflecting the functional properties of the mathematically modelled presynaptic slow transport processes, is introduced.


Subject(s)
Axonal Transport/physiology , Models, Neurological , Nervous System/metabolism , Neuropeptides/metabolism , Presynaptic Terminals/metabolism , Synaptic Transmission/physiology , Algorithms , Animals , Calcium/metabolism , Calcium Signaling/physiology , Cell Compartmentation/physiology , Computer Simulation , Diffusion , Humans , Secretory Vesicles/metabolism
9.
J Math Biol ; 56(4): 559-76, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17924107

ABSTRACT

In this paper a methodology of mathematical description of the synthesis, storage and release of the neurotransmitter during the fast synaptic transport is presented. The proposed model is based on the initial and boundary value problem for a parabolic nonlinear partial differential equation (PDE). Presented approach enables to express space and time dependences in the process: rate of vesicular replenishment, gradients of vesicular concentration and, through the boundary conditions, the location of docking and release sites. The model should be a good starting point for future numerical simulations since it is based on thoroughly studied parabolic equation. In the article classical and variational formulation of the problem is presented and the unique solution is shown to exist. The model is referred to the model based on ordinary differential equations (ODEs), created by Aristizabal and Glavinovic (AG model). It is shown that, under some assumptions, AG model is a special case of the introduced one.


Subject(s)
Axonal Transport/physiology , Models, Neurological , Neurotransmitter Agents/metabolism , Presynaptic Terminals/physiology , Animals , Cell Communication/physiology , Diffusion , Humans , Kinetics , Membrane Fusion , Metabolic Clearance Rate , Nonlinear Dynamics , Numerical Analysis, Computer-Assisted , Synaptic Transmission/physiology , Synaptic Vesicles/metabolism
10.
Psychiatr Pol ; 37(4): 703-12, 2003.
Article in Polish | MEDLINE | ID: mdl-14560498

ABSTRACT

The concept of information metabolism was introduced by prof. Kepinski at the end of the 1960-ies of the 20th century. The article presents the synthesis of a series of papers aiming to concrete, update and describe in mathematical terms the concept of metabolism of information. Theoretical basis of the model in the context of the theory of information and the main structures and functions of the metabolism of information are presented. These structures are: control centre (nucleus), boundaries (cell membrane), functional structures (endoplasmic reticulum), energy centres (mitochondria), synthesis centres (ribosoms) and elimination centres (lysosoms). At the end, the publications on the mathematical description of the information metabolism model are presented and discussed.


Subject(s)
Brain/metabolism , Consciousness , Mental Processes , Decision Making , Humans , Mental Disorders , Models, Psychological , Personality Development , Psychotherapy
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