scholarly journals Heating and Cooling Anomaly of a Rotating Body

10.14311/664 ◽  
2005 ◽  
Vol 45 (1) ◽  
Author(s):  
O. Brůha ◽  
T. Brůha

This paper deals with an effect which appears when heating or cooling a rotating body. No external forces acting on the body are supposed. Due to thermal expansion, the moment of inertia of the body varies together with the temperature changes. In agreement with the principle of conservation of angular momentum [1], the angular momentum is constant. This results in angular velocity changes and subsequently in kinetic energy changes. Also the stress energy varies together with the changes in thermal dimension. To satisfy the principle of energy conservation we have to suppose that the changes in kinetic and stress energy are compensated by the changes in internal energy, which is correlated with temperature changes of the body. This means that the rules for the heating or cooling process of a rotating body are not the same as those for a body at rest. This idea, applied to a cylinder rotating around its geometric axis under specific parameters, has been mathematically treated. As a result, the difference between the final temperature of the rotating cylinder and the temperature of the cylinder at rest has been found. 

2021 ◽  
Vol 11 (15) ◽  
pp. 6900
Author(s):  
Su-Kyung Sung ◽  
Sang-Won Han ◽  
Byeong-Seok Shin

Skinning, which is used in skeletal simulations to express the human body, has been weighted between bones to enable muscle-like motions. Weighting is not a form of calculating the pressure and density of muscle fibers in the human body. Therefore, it is not possible to express physical changes when external forces are applied. To express a similar behavior, an animator arbitrarily customizes the weight values. In this study, we apply the kernel and pressure-dependent density variations used in particle-based fluid simulations to skinning simulations. As a result, surface tension and elasticity between particles are applied to muscles, indicating realistic human motion. We also propose a tension yield condition that reflects Tresca’s yield condition, which can be easily approximated using the difference between the maximum and minimum values of the principal stress to simulate the tension limit of the muscle fiber. The density received by particles in the kernel is assumed to be the principal stress. The difference is calculated by approximating the moment of greatest force to the maximum principal stress and the moment of least force to the minimum principal stress. When the density of a particle increases beyond the yield condition, the object is no longer subjected to force. As a result, one can express realistic muscles.


2010 ◽  
Vol 35 (1) ◽  
pp. 43-53 ◽  
Author(s):  
ROB BAUM

A remembered piece of student theatre returns the writer to an examination of what was staged: a play centring on survival of the Shoah; the actor himself, a survivor; or an old man's self-discovery in the theatre. A shocking gestus in this production broke the boundaries of theatre and (while the fourth wall remained intact) transformed the audience into witnesses, and theatre into testimony. The article theorizes traumatic memory and its manifestations in the body, trauma's staging and the shape of narrative, and the difference between history, its performance and its mark.


1986 ◽  
Vol 114 ◽  
pp. 35-40 ◽  
Author(s):  
T. Fukushima

The definition of the angular momentum of a finite body is given in the post-Newtonian framework. The non-rotating and the rigidly rotating proper reference frame(PRF)s attached to the body are introduced as the basic coordinate systems. The rigid body in the post-Newtonian framework is defined as the body resting in a rigidly rotating PRF of the body. The feasibility of this rigidity is assured by assuming suitable functional forms of the density and the stress tensor of the body. The evaluation of the time variation of the angular momentum in the above two coordinate systems leads to the post-Newtonian Euler's equation of motion of a rigid body. The distinctive feature of this equation is that both the moment of inertia and the torque are functions of the angular velocity and the angular acceleration. The obtained equation is solved for a homogeneous spheroid suffering no torque. The post-Newtonian correction to the Newtonian free precession is a linear combination of the second, fourth and sixth harmonics of the precessional frequency. The relative magnitude of the correction is so small as of order of 10−23 in the case of the Earth.


Author(s):  
Gr.G. Khubulava

Relevance. Movement surrounds and accompanies us everywhere: planets move, time, river waters, the life of cities is accompanied by traffic along highways. Our own life is also inseparable from the phenomenon of movement, both at the micro and macro levels: whether it be the movement and division of atoms of matter and cells of the body, the movement and interaction of our bodies in space, or the movement of a person towards a specific goal, conditioned by intention and expressed in actions, which in themselves are also a movement of the will. Purpose: to describe and evaluate the nature of the phenomenon of movement both in the history of philosophy (from Zeno to Descartes and Bergson) and in the history of medicine (from Aristotle and Celsus to modern mechanisms that give a person a chance to return the possibility of movement as an aspect of full life). Methods: the research method is not only the analysis of the development of the phenomenon of movement in the history of philosophy and science, but also the analysis of the influence of modern technologies on the very understanding of the nature of movement not as a physiological, but as an ontological phenomenon. Results. The ancient idea of movement as a deception of the senses, describing the closed on itself the existence of an objectively motionless space or being the source and cause of eternally arising and disintegrating existence, was an attempt by thinkers to “catch the mind on being”, not just creating a picture of a single cosmos, but also comprehending him as part of the human world. The bodily movement and structure of a person was understood as part of the visible and speculative structure of being. The thought of the Middle Ages, which understood movement as the path of the world and man to God, perceived the phenomenon of movement as an expression of free will and, at the same time, the desire of the world to its completion, which is at the same time the moment of its transformation. The Renaissance epoch, which proclaimed man as an end in itself for existence, closely links the physical movement of man with the movement of the cosmos, and considers the visible nature to be the source of knowledge of the Divine Will. The New Time, which theoretically separated the mechanics of the bodily and the impulses of the soul and mind and declared man a “biological machine”, in fact does not break the relationship between the movement of the soul and the body, but, demonstrating the difference in the nature of these movements, anticipated the discovery of psychosomatics. Finally, modern times not only created a classification of “body techniques” inherent in various stages of human life and groups of people, describing the socio-cultural aspect of corporeality, but also perceived movement as an act of our existence and involvement in the existence of the world. Conclusion. Movement cannot be understood as a purely physiological act. In the process of growth, becoming, having barely learned to walk, we are faced with the need to perform actions, to “behave”, to be like a personal I and as a part of the moving world that collided with us. A world in which every step is an event and deed capable of defining “the landscape of our personal and universal being”.


Author(s):  
Yu.Yu. Kolbas ◽  
M.A. Ivanov

The paper addresses time and temperature zero drifts in Zeeman laser gyroscope (RLG) operating in the mode of periodic adjustment of RLG to the longitudinal mode of generation with the opposite circular polarization of the light wave. In such a gyroscope, the zero drift can be divided into magnetic and non-magnetic components having different nature and making a significantly different contribution to the final error. Algorithmic methods are proposed for mathematical compensation of RLG zero drift, both with and without using initial calibration. It is shown that the simultaneous use of reproducible dependencies of the magnetic and non-magnetic zero drifts due to RLG temperature changes allows solving the problem of RLG zero drift correction in the optimal way. The correction factors are calculated from the temperature of a Zeeman laser gyro at the moment of activation. At the same time, using the difference between the temperatures of the gyroscope and gyro case, where it is installed, it is possible to determine the temperature of the Zeeman laser gyroscope at the moment of switching on, thereby eliminating the problem of calculating the correction factors when the gyroscope is turned off and then on again. Experimental results for several Zeeman laser gyroscopes with typical values of zero drifts are presented


2018 ◽  
Vol 12 (2) ◽  
pp. 56-70
Author(s):  
Sonja Weiss

This paper reconsiders the role of memory in Plotinus' philosophy, in view of the mystical unity (hénosis) of the soul with intelligible truths, and a less desirable unification with its objects of memory during its earthly existence. As a rule, the mystical experience precludes memory, since the latter is related to time and binds a man to his individuality. Nevertheless, the capacity to remember remains an important part of the philosophical áskesis leading to this experience, since the memory is the only faculty of the soul that is able to travel through time, even though it is part of the process of discursive thinking and consequently is in a way imprisoned in time. Memory therefore turns out to be a double-edged power, which leaves us to question when we can regard it as an instrument of preserving what is inherent to us, and when, on the other hand, it is simply chaining us to the lower reality of the sensible world. The difference between the anagogical power of the Platonic recollection (anámnesis) and the memory as the state keeping us from unity with the intelligible world is important for identifying the moment when a man must let go of what he has been clinging to. This moment, however, is not set in time, but depends on the moral disposition of a man's soul leading a timeless existence outside, as well as inside, the body.


2014 ◽  
Vol 23 (1-2) ◽  
pp. 1-22
Author(s):  
Cristina Botezatu ◽  
Carmen Andrei ◽  
Pierre Joseph de Hillerin

Abstract Anticipation is a crucial factor in acquiring motor skills. Generally, the anticipation involves the presence of a proactive control. The success of some actions in the sporting events depends on the player’s ability to quickly perceive the situations and to react immediately on them. In this context, anticipation refers to the response triggered by a stimulus before it appears. The difference between the anticipation and reaction rest in the fact that the reaction occurs after the stimulus appears, as for the anticipation, the neuromuscular mobilization occurs before the moment triggered by the appearance of the stimulus. Both concepts are interrelated. Therefore, an optimal anticipation will lead to an apparently very good reaction response, using different, by nature and location, mechanisms in the psycho-neuromotor chain. The goal of this research paper is to highlight certain objective elements in the dynamic training of the body forfuture contact and, after that to obtain an indicatory optimal anticipation, with the intention to use it in the primary selection phase in sports, demanding highly coordination skills.


Author(s):  
Gr.G. Khubulava

Relevance. Movement surrounds and accompanies us everywhere: planets move, time, river waters, the life of cities is accompanied by traffic along highways. Our own life is also inseparable from the phenomenon of movement, both at the micro and macro levels: whether it be the movement and division of atoms of matter and cells of the body, the movement and interaction of our bodies in space, or the movement of a person towards a specific goal, conditioned by intention and expressed in actions, which in themselves are also a movement of the will. Purpose: to describe and evaluate the nature of the phenomenon of movement both in the history of philosophy (from Zeno to Descartes and Bergson) and in the history of medicine (from Aristotle and Celsus to modern mechanisms that give a person a chance to return the possibility of movement as an aspect of full life). Methods: the research method is not only the analysis of the development of the phenomenon of movement in the history of philosophy and science, but also the analysis of the influence of modern technologies on the very understanding of the nature of movement not as a physiological, but as an ontological phenomenon. Results. The ancient idea of movement as a deception of the senses, describing the closed on itself the existence of an objectively motionless space or being the source and cause of eternally arising and disintegrating existence, was an attempt by thinkers to “catch the mind on being”, not just creating a picture of a single cosmos, but also comprehending him as part of the human world. The bodily movement and structure of a person was understood as part of the visible and speculative structure of being. The thought of the Middle Ages, which understood movement as the path of the world and man to God, perceived the phenomenon of movement as an expression of free will and, at the same time, the desire of the world to its completion, which is at the same time the moment of its transformation. The Renaissance epoch, which proclaimed man as an end in itself for existence, closely links the physical movement of man with the movement of the cosmos, and considers the visible nature to be the source of knowledge of the Divine Will. The New Time, which theoretically separated the mechanics of the bodily and the impulses of the soul and mind and declared man a “biological machine”, in fact does not break the relationship between the movement of the soul and the body, but, demonstrating the difference in the nature of these movements, anticipated the discovery of psychosomatics. Finally, modern times not only created a classification of “body techniques” inherent in various stages of human life and groups of people, describing the socio-cultural aspect of corporeality, but also perceived movement as an act of our existence and involvement in the existence of the world. Conclusion. Movement cannot be understood as a purely physiological act. In the process of growth, becoming, having barely learned to walk, we are faced with the need to perform actions, to “behave”, to be like a personal I and as a part of the moving world that collided with us. A world in which every step is an event and deed capable of defining “the landscape of our personal and universal being”.


2000 ◽  
Vol 15 (17) ◽  
pp. 1107-1115
Author(s):  
F. I. COOPERSTOCK

Recently we demonstrated that Eddington's spinning rod lost "kinetic" energy but preserved its total energy while emitting gravitational waves. Additional information is now determined by analyzing the angular momentum of the rod. We develop an expression for the angular momentum loss of the material system alone with an integration over the source region. As expected, it is found that the moment of inertia of the rod increases as the rotation rate diminishes in analogy with typical classical systems. Its rate of change is determined in relation to the angular deceleration of the body.


Jurnal NERS ◽  
2020 ◽  
Vol 14 (3) ◽  
pp. 321
Author(s):  
Aaulya Kartini Dg Karra ◽  
Muh Aswar Anas ◽  
Muhammad Anwar Hafid ◽  
Rosdianah Rahim

Introduction: The use of warm compresses and warm sponge techniques as a modality therapy for the management of fever in typhoid children has a good influence. The purpose of this research was to learn of the differences between conventional warm compress and the tepid sponge technique as related to the body temperature changes of pediatric patients with typhoid fever. A fever that does not get a good standard of treatment can cause dehydration, neurological damage and febrile seizures.Methods: The research design was quasi-experiment with two groups pre-post test. The population was taken from the Kampili Community Health Center while the 20 samples were taken using the purposive sampling technique. Conventional warm compresses were placed on the forehead, while warm tepid sponges were compressed and placed on the forehead, armpits and the folds of the thighs simultaneously.Results: . The data of the results were significance tested using the General linear model repeated measure (p value 0.03 for conventional warm compresses and p value 0.01 on a warm compress tepid sponge technique).Conclusion: Statistically, the warm compress tepid sponge technique is more meaningful and qualitatively, the temperature change is better after the compression.


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