scholarly journals The Periodic Solutions for Planar -Body Problems

2013 ◽  
Vol 2013 ◽  
pp. 1-10
Author(s):  
Xiaohong Hu ◽  
Changrong Zhu
Keyword(s):  
Periodic Solutions ◽  
Necessary Conditions ◽  
The Body ◽  
Planar Body

Based on the works of Perko and Walter, Moeckel and Simo, and Zhang and Zhou, we study the necessary conditions and suffcient conditions for the uniformly rotating planar nested regular polygonal periodic solutions for the -body problems.

scholarly journals On the equivalence of three-dimensional differential systems

2020 ◽  
Vol 18 (1) ◽  
pp. 1164-1172
Author(s):  
Jian Zhou ◽  
Shiyin Zhao
Keyword(s):  
Periodic Solutions ◽  
Differential System ◽  
Necessary Conditions ◽  
Three Dimensional ◽  
Sufficient Conditions ◽  
Periodic Systems ◽  
Structural Form ◽  
Differential Systems

Abstract In this paper, firstly, we study the structural form of reflective integral for a given system. Then the sufficient conditions are obtained to ensure there exists the reflective integral with these structured form for such system. Secondly, we discuss the necessary conditions for the equivalence of such systems and a general three-dimensional differential system. And then, we apply the obtained results to the study of the behavior of their periodic solutions when such systems are periodic systems in t.

Regional blood flow measurement in vivo for a definable geometry

1964 ◽  
Vol 206 (5) ◽  
pp. 962-966 ◽  
Author(s):  
Marvin B. Bacaner ◽  
James S. Beck
Keyword(s):  
Blood Flow ◽  
Flow Measurement ◽  
Necessary Conditions ◽  
Regional Blood Flow ◽  
The Body ◽  
Continuous Measure ◽  
Radioisotope Method ◽  
Arterial Concentration ◽  
Regional Concentration

A radioisotope method for measuring regional blood flow in the intestine of the dog in vivo has been favorably compared with measurement by timed collection of total venous outflow. The necessary conditions are a continuous measure of arterial concentration and cumulative regional concentration of radioisotope, an experimentally definable region, and temporary complete retention of tracer. The derivation of the relations used suggests additional applications of the method to other regions of the body.

scholarly journals Brain as agent and conscious mind as action guide: from Libet-style experiments to necessary conditions for free will

2021 ◽  
Vol 22 (1) ◽  
pp. 78-83
Author(s):  
Jonas Gonçalves Coelho
Keyword(s):  
Free Will ◽  
Necessary Conditions ◽  
Brain Activity ◽  
The Body ◽  
General View ◽  
Conscious Mind ◽  
Sociocultural Environment ◽  
Starting Point ◽  
Conscious Intention ◽  
The Brain

Many neuroscientific experiments, based on monitoring brain activity, suggest that it is possible to predict the conscious intention/choice/decision of an agent before he himself knows that. Some neuroscientists and philosophers interpret the results of these experiments as showing that free will is an illusion, since it is the brain and not the conscious mind that intends/chooses/decides. Assuming that the methods and results of these experiments are reliable the question is if they really show that free will is an illusion. To address this problem, I argue that first it is needed to answer three questions related to the relationship between conscious mind and brain: 1. Do brain events cause conscious events? 2. Do conscious events cause brain events? 3. Who is the agent, that is, who consciously intends/chooses/ decides, the conscious mind, the brain, or both? I answer these questions by arguing that the conscious mind is a property of the brain due to which the brain has the causal capacity to interact adaptively with its body, and trough the body, with the physical and sociocultural environment. In other words, the brain is the agent and the conscious mind, in its various forms - cognitive, volitional and emotional - and contents, is its guide of action. Based on this general view I argue that the experiments aforementioned do not show that free will is an illusion, and as a starting point for examining this problem I point out, from some exemplary situations, what I believe to be some of the necessary conditions for free will.Key-words: Agent brain, conscious mind, free will, Libet-style experiments.

Energy Comparison Between Trot, Bound, and Gallop Using a Simple Model

1995 ◽  
Vol 117 (4) ◽  
pp. 466-473 ◽  
Author(s):  
P. Nanua ◽  
K. J. Waldron
Keyword(s):  
Simple Model ◽  
Periodic Solutions ◽  
Energy Levels ◽  
The Body ◽  
Experimental Results ◽  
Gait Transition ◽  
Transition Speed ◽  
Quadruped Trot

In this paper, the dynamics of quadruped trot, gallop, and bound will be examined using a simple model for the quadruped. The body of the quadruped is modeled as a uniform bar and the legs are modeled by massless springs. It will be shown that symmetry can be used to study the locomotion of this system. Using symmetry, a technique will be developed to obtain periodic solutions for each of the gaits of the quadruped model. These periodic solutions will be computed at various speeds. The energy levels will be compared for each of the gaits. The exchange of energy between its different forms will be shown for different gaits. It will be shown that even without body flexibility, there are significant savings in energy due to gait transition from trot to gallop. The energy levels will be used to predict the trot-gallop transition speed. These results will be compared with the experimental results for horses and dogs.

Personal Identity and the Body

Dialogue ◽  
1971 ◽  
Vol 10 (3) ◽  
pp. 458-478 ◽  
Author(s):  
Bernard Gert
Keyword(s):  
Personal Identity ◽  
Nobel Prize ◽  
Necessary Conditions ◽  
Sufficient Conditions ◽  
The Body

I see someone who looks vaguely familiar. I wonder if he could be the same person I had a fight with on my birthday ten years ago. I hear that some scientist has received the Nobel prize in chemistry for some work very similar to that which interested the brightest boy in my chemistry class twenty years ago. I wonder if that scientist and the brightest boy might be the same person. What facts, if they could be discovered, would be decisive in answering these questions? Are there any facts that, if it turns out that they do not obtain, would show conclusively that the two people are not the same person? That is, are there any necessary conditions for personal identity? Are there any facts that, if it turns out that they do obtain, would show conclusively that the two people are the same person? That is, are there any sufficient conditions for personal identity?

scholarly journals Swim-like motion of bodies immersed in an ideal fluid

2019 ◽  
Vol 25 ◽  
pp. 16 ◽  
Author(s):  
Marta Zoppello ◽  
Franco Cardin
Keyword(s):  
Recent Literature ◽  
The Body ◽  
Riemann Mapping Theorem ◽  
First Order ◽  
Order Expansion ◽  
And Control ◽  
Small Deformations ◽  
Initial Impulse ◽  
Shape Changes ◽  
Planar Body

The connection between swimming and control theory is attracting increasing attention in the recent literature. Starting from an idea of Alberto Bressan [A. Bressan, Discrete Contin. Dyn. Syst. 20 (2008) 1–35]. we study the system of a planar body whose position and shape are described by a finite number of parameters, and is immersed in a 2-dimensional ideal and incompressible fluid in terms of gauge field on the space of shapes. We focus on a class of deformations measure preserving which are diffeomeorphisms whose existence is ensured by the Riemann Mapping Theorem. After making the first order expansion for small deformations, we face a crucial problem: the presence of possible non vanishing initial impulse. If the body starts with zero initial impulse we recover the results present in literature (Marsden, Munnier and oths). If instead the body starts with an initial impulse different from zero, the swimmer can self-propel in almost any direction if it can undergo shape changes without any bound on their velocity. This interesting observation, together with the analysis of the controllability of this system, seems innovative.

scholarly journals High energy, increased balance and self control, the necessary conditions for performance and a good health

2018 ◽  
Vol 12 (1) ◽  
pp. 579-591 ◽  
Author(s):  
Lucian T. Mândrea ◽  
Ioan I. Curta ◽  
Zoltan Z. Marosy
Keyword(s):  
Necessary Conditions ◽  
Personal Control ◽  
Good Health ◽  
High Energy ◽  
The Body ◽  
Self Control ◽  
Human Being ◽  
Original Result ◽  
The Subject ◽  
High Level

Abstract The research purpose is to present the possibilities of the human being which are useful in order to improve the personal level of energy and to achieve an increased balance and a strong self control. These are the necessary conditions to be performed and in the same time to maintain a good health. Humans usually use energy from external sources. But, first of all, by employing different personal techniques, one can reach a high level of balance, energy and self control. These are the simplest, the fastest, the most efficient, the most economical and also ecological ways to have energy. If these attempts are efficient, you are first of all warm, then less ill and stressed. Everybody should try these kinds of methods first. A comparison was made between the results from two consecutive years, obtained by measuring the subject using a Bio-Well device. It results an increase of 23% in the energy level, in the conditions that the other parameters are optimal. The general balance reached the value of 99.97%. The authors proved, with the occasion of these original measurements, that a perfect balance can be reached. Another set of original and new measurements reveal the possibility of the human being to have a good self control. The subject proposed and succeeded in moving the second body energy centre by his own will, which is the most important energy centre of the body in the Zen-Buddhism. This is a remarkable completely original result obtained, maybe, for the first time in the world. In principle, we could control then the positions of the all seven energy centers, one by one. And so, the whole balance of the body. Also, in this way an incredible personal control and level of performance and also a high level of happiness can be achieved.

scholarly journals Applying the Large Parameter Technique for Solving a Slow Rotary Motion of a Disc about a Fixed Point

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
A. I. Ismail
Keyword(s):  
Fixed Point ◽  
Angular Velocity ◽  
Periodic Solutions ◽  
Numerical Solutions ◽  
Initial Conditions ◽  
Numerical Technique ◽  
Equations Of Motion ◽  
First Integral ◽  
The Body ◽  
Large Parameter

In this paper, the motion of a disk about a fixed point under the influence of a Newtonian force field and gravity one is considered. We modify the large parameter technique which is achieved by giving the body a sufficiently small angular velocity component r0 about the fixed z-axis of the disk. The periodic solutions of motion are obtained in the neighborhood r0 tends to 0. This case of study is excluded from the previous works because of the appearance of a singular point in the denominator of the obtained solutions. Euler-Poison equations of motion are obtained with their first integrals. These equations are reduced to a quasilinear autonomous system of two degrees of freedom and one first integral. The periodic solutions for this system are obtained under the new initial conditions. Computerizing the obtained periodic solutions through a numerical technique for validation of results is done. Two types of analytical and numerical solutions in the new domain of the angular velocity are obtained. Geometric interpretations of motion are presented to show the orientation of the body at any instant of time t.

scholarly journals Embodied and Situated Aesthetics; An enactive approach to a cognitive notion of aesthetics

Artnodes ◽  
2017 ◽  
pp. 20-27 ◽  
Author(s):  
Alex Arteaga
Keyword(s):  
Complex System ◽  
Cognitive Function ◽  
Autonomous System ◽  
Necessary Conditions ◽  
The Body ◽  
Cognitive Approach ◽  
Structural Coupling ◽  
Enactive Approach ◽  
Conceptual Construction ◽  
New Research

This text presents a first attempt to specify the cognitive function of aesthetics or, to put it in more radical terms, to define aesthetics as a variety of cognition . Due to the inaugural character of this essay—although it is rooted in my former work, it initiates a new research environment—it merely outlines key ideas in this regard. It maps out a territory which begins to emerge through the landmarks that delineate it. Accordingly, this text does not include detailed argumentations about the proposed ideas. It simply defines the infrastructure of a conceptual construction that will be enabled and precisely realized in the coming years. This endeavor is framed by the so-called theories of embodied and situated cognition and more specifically the enactive approach. According to the first, cognition takes place due to two necessary conditions: the activities of bodies—biological realized organisms—and their entanglement with their surroundings. Cognition thus cannot occur on the basis of an ideal entity—e.g. a “pure mind”—in a vacuum or “neutral container.” The enactive approach specifies these basic conditions, defining the body as an autonomous system and its involvement with the environment as structural coupling. Furthermore, this cognitive approach explains the relationships between living units and their surroundings in terms of co-emergence: a dynamic and complex system of mutual determination between enabling conditions and emerging qualities.

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