Entropy approach in the estimation of parameters of cardio schoolboys at latitudinal

2015 ◽  
Vol 4 (2) ◽  
pp. 20-28
Author(s):  
Ястребов ◽  
A. Yastrebov ◽  
Горбунов ◽  
D. Gorbunov ◽  
Эльман ◽  
...  
Keyword(s):  
Distribution Function ◽  
Lyapunov Exponent ◽  
Chaotic Systems ◽  
Diagnostic Value ◽  
Estimation Of Parameters ◽  
Initial State ◽  
Time Intervals ◽  
Climatic Zones ◽  
Continuous State ◽  
And Performance

Options cardio demonstrate the instability of the distribution function f (x) for different time intervals of measurements Δt. We postulate that such systems can not be attributed to the traditional chaotic systems, as for them it is impossible to calculate the autocorrelation function, Lyapunov exponent, no mixing and performance properties of continuous state vector x (t) demonstrates the chaotic motion in the form dx / dt ≠ 0. Since the initial state x (t0) can not be repeated arbitrarily for such systems, there is the uncertainty of the 1st and the 2nd type. Entropy approach is proposed for describing the assessment of the behavior of cardio when changing climatic zones. Compares the value of the results of quasi-attractors samples cardio area and the values of the Shannon entropy. The examples of such a situation for the parameters of cardio groups of children at Ugra latitudinal displacements. It demonstrated that the entropy approach has a low diagnostic value in the evaluation of samples of cardio.

Accuracy of estimation of time-intervals in psychogeriatric outpatients

2012 ◽  
Vol 24 (5) ◽  
pp. 809-821 ◽  
Author(s):  
Jeremia Heinik
Keyword(s):  
The Elderly ◽  
Diagnostic Value ◽  
Absolute Accuracy ◽  
Cognitive Measures ◽  
Time Intervals ◽  
Cognitive Correlates ◽  
Diagnostic Role ◽  
And Performance ◽  
Estimation Of Time ◽  
Cognitive Data

ABSTRACTBackground: Accuracy of estimation of time-intervals has received marginal attention in psychogeriatrics. We examined presumed differences in this time measure in participants with dementia (PWD) versus participants without dementia (PWoutD), further subdivided into specific diagnoses and performance subgroups. We also studied its demographic, clinical, and cognitive correlates and predictors. A diagnostic role was hypothesized.Methods: Forty-three individuals (27 PWD: 16 dementia of the Alzheimer's type (DAT), 11 vascular dementia (VaD); 16 PWoutD: 10 major depressive disorder (MDD), 6 normal) were interviewed with the Cambridge Examination for Mental Disorders of the Elderly – Revised (CAMDEX-R) that permits the registration of this time measure. Demographic, clinical, and cognitive data were obtained.Results: Neither absolute accuracy of estimation of duration of interview nor its transformed logarithm were significantly different between PWD and PWoutD, or between DAT and VaD participants. MDD participants performed significantly poorer than normal and did not differ from PWD, and the PWD relatively better performing subgroup. The logarithm of absolute accuracy of estimation correlated with some clinical and cognitive variables. Only a measure of depression and of impaired judgment could significantly predict it.Conclusions: The absolute accuracy of estimation of time-intervals did not differ between the major groups and the main diagnoses subgroups. It was associated with a variety of clinical and cognitive measures, and was predicted by the composite constructs of depression and impaired judgment. The diagnostic value of this measure in the psychogeriatric clinic is questionable, and limited to “worried” well individuals.

scholarly journals Lyapunov decay in quantum irreversibility

2016 ◽  
Vol 374 (2069) ◽  
pp. 20150157 ◽  
Author(s):  
Ignacio García-Mata ◽  
Augusto J. Roncaglia ◽  
Diego A. Wisniacki
Keyword(s):  
Hilbert Space ◽  
Quantum Mechanics ◽  
Lyapunov Exponent ◽  
Haar Measure ◽  
Chaotic Systems ◽  
Initial State ◽  
Infinite Dimensional ◽  
Infinite Dimensional Hilbert Space ◽  
Dimensional Hilbert Space ◽  
Loschmidt Echo

The Loschmidt echo—also known as fidelity—is a very useful tool to study irreversibility in quantum mechanics due to perturbations or imperfections. Many different regimes, as a function of time and strength of the perturbation, have been identified. For chaotic systems, there is a range of perturbation strengths where the decay of the Loschmidt echo is perturbation independent, and given by the classical Lyapunov exponent. But observation of the Lyapunov decay depends strongly on the type of initial state upon which an average is carried out. This dependence can be removed by averaging the fidelity over the Haar measure, and the Lyapunov regime is recovered, as has been shown for quantum maps. In this work, we introduce an analogous quantity for systems with infinite dimensional Hilbert space, in particular the quantum stadium billiard, and we show clearly the universality of the Lyapunov regime.

Features Samples Cardiointervals: Chaos and Stochastics in the Description of Complex Biosystems

2015 ◽  
Vol 22 (2) ◽  
pp. 19-26
Author(s):  
Горбунов ◽  
D. Gorbunov ◽  
Синенко ◽  
D. Sinenko ◽  
Козлова ◽  
...  
Keyword(s):  
Lyapunov Exponent ◽  
Chaotic Systems ◽  
Binary Classification ◽  
Order Parameters ◽  
Self Organization ◽  
Initial State ◽  
Diagnostic Signs ◽  
Large Groups ◽  
Complex Biosystems ◽  
Number Of Iterations

Complex Biosystems (complexity) cannot be attributed to traditional chaotic systems, because for them it is impossible to calculate the autocorrelation function, Lyapunov exponent, no run properties of mixing, continuously the state vector x(t) demonstrates chaotic motion in the form άχίάίΦθ. Since the initial state x(to) is arbitrarily unrepeatable for such systems, type-one uncertainty and type-two uncertainty arise. Type-one uncertainty is characterized by absence of statistically significant differences between samples. The authors propose neurocomputing methods and theory of chaos and self-organization to differentiate these samples. The authors present examples of such a situation for the parameters of the cardio-respiratory system of humans in conditions of the latitudinal displacement of large groups of people. It is shown that the neuroemulator not only solves the problem of binary classification, but also identifies the order parameters in diagnostic signs. It is very important to increase the number of iterations in the repetition of binary classification. The number of iteration (when we repeat the neuroemulator procedure) has the fundamental role for identification of order parameters. Errors are possible within the order parameters with the high number of iterations.

scholarly journals Evaluation of the Possibility of Using 1.4462 and 1.4501 Steel as a Construction Material for Apparatus Operating at an Increased Temperature and with Corrosive Factors

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4014
Author(s):  
Karol Prałat ◽  
Andżelika Krupińska ◽  
Marek Ochowiak ◽  
Sylwia Włodarczak ◽  
Magdalena Matuszak ◽  
...  
Keyword(s):  
Construction Material ◽  
Construction Materials ◽  
Optical Microscope ◽  
Passive Layer ◽  
Initial State ◽  
Time Intervals ◽  
Significant Deterioration ◽  
Higher Temperature ◽  
Increasing Temperature ◽  
Steel Heat

The objective of this study was to determine the requirements for steels used as construction materials for chemical apparatus operating at an elevated temperature and to correlate them with the properties of the tested steels. The experimental part examined the influence of the annealing process on the structure and properties of X2CrNiMoN22-5-3 (1.4462) and X2CrNiMoCuWN25-7-4 (1.4501) steel. Heat treatment was carried out on the tested samples at a temperature of 600 °C and 800 °C. Changes were observed after the indicated time intervals of 250 and 500 h. In order to determine the differences between the initial state and after individual annealing stages, metallographic specimens were performed, the structure was analyzed using an optical microscope and the micro-hardness was measured using the Vickers method. Potentiostatic tests of the samples were carried out to assess the influence of thermal process parameters on the electrochemical properties of the passive layer. An increase in the hardness of the samples was observed with increasing temperature and annealing time, the disappearance of magnetic properties for both samples after annealing at the temperature of 800 °C, as well as a significant deterioration in corrosion resistance in the case of treatment at a higher temperature.

Discrete-Time Memristor Model for Enhancing Chaotic Complexity and Application in Secure Communication

2022 ◽  
Author(s):  
Wenhao Yan ◽  
Zijing Jiang ◽  
Qun Ding
Keyword(s):  
Fixed Points ◽  
Discrete Time ◽  
Dynamic Characteristics ◽  
Secure Communication ◽  
Chaotic Systems ◽  
Two Dimensional ◽  
Initial State ◽  
One Dimensional ◽  
Backward Euler ◽  
Short Period

Abstract The physical implementation of continuoustime memristor makes it widely used in chaotic circuits, whereas discrete-time memristor has not received much attention. In this paper, the backward-Euler method is used to discretize TiO2 memristor model, and the discretized model also meets the three fingerprinter characteristics of the generalized memristor. The short period phenomenon and uneven output distribution of one-dimensional chaotic systems affect their applications in some fields, so it is necessary to improve the dynamic characteristics of one-dimensional chaotic systems. In this paper, a two-dimensional discrete-time memristor model is obtained by linear coupling the proposed TiO2 memristor model and one-dimensional chaotic systems. Since the two-dimensional model has infinite fixed points, the stability of these fixed points depends on the coupling parameters and the initial state of the discrete TiO2 memristor model. Furthermore, the dynamic characteristics of one-dimensional chaotic systems can be enhanced by the proposed method. Finally, we apply the generated chaotic sequence to secure communication.

MUTUAL AND SELF-COMPOUNDING OF CHAOTIC SYSTEMS

1996 ◽  
Vol 06 (04) ◽  
pp. 759-767
Author(s):  
R. SINGH ◽  
P.S. MOHARIR ◽  
V.M. MARU
Keyword(s):  
Lyapunov Exponent ◽  
Lyapunov Exponents ◽  
Chaotic System ◽  
Dynamic Systems ◽  
Mantle Convection ◽  
Chaotic Systems ◽  
Compound System ◽  
Two Systems

The notion of compounding a chaotic system was introduced earlier. It consisted of varying the parameters of the compoundee system in proportion to the variables of the compounder system, resulting in a compound system which has in general higher Lyapunov exponents. Here, the notion is extended to self-compounding of a system with a real-earth example, and mutual compounding of dynamic systems. In the former, the variables in a system perturb its parameters. In the latter, two systems affect the parameters of each other in proportion to their variables. Examples of systems in such compounding relationships are studied. The existence of self-compounding is indicated in the geodynamics of mantle convection. The effect of mutual compounding is studied in terms of Lyapunov exponent variations.

scholarly journals Probability distributions of COVID-19 tweet posted trends use a nonhomogeneous Poisson process

2020 ◽  
Vol 1 (4) ◽  
pp. 229-238
Author(s):  
Devi Munandar ◽  
Sudradjat Supian ◽  
Subiyanto Subiyanto
Keyword(s):  
Social Media ◽  
Poisson Process ◽  
Exponential Distribution ◽  
Probability Distributions ◽  
Nonhomogeneous Poisson Process ◽  
Time Interval ◽  
Initial State ◽  
Time Intervals ◽  
Time Parameters ◽  
Parameter Values

The influence of social media in disseminating information, especially during the COVID-19 pandemic, can be observed with time interval, so that the probability of number of tweets discussed by netizens on social media can be observed. The nonhomogeneous Poisson process (NHPP) is a Poisson process dependent on time parameters and the exponential distribution having unequal parameter values and, independently of each other. The probability of no occurrence an event in the initial state is one and the probability of an event in initial state is zero. Using of non-homogeneous Poisson in this paper aims to predict and count the number of tweet posts with the keyword coronavirus, COVID-19 with set time intervals every day. Posting of tweets from one time each day to the next do not affect each other and the number of tweets is not the same. The dataset used in this study is crawling of COVID-19 tweets three times a day with duration of 20 minutes each crawled for 13 days or 39 time intervals. The result of this study obtained predictions and calculated for the probability of the number of tweets for the tendency of netizens to post on the situation of the COVID-19 pandemic.

STABILIZATION OF CHAOTIC SYSTEMS USING LINEAR SAMPLED-DATA CONTROLLER

2007 ◽  
Vol 17 (06) ◽  
pp. 2021-2031 ◽  
Author(s):  
H. K. LAM ◽  
F. H. F. LEUNG
Keyword(s):  
Chaotic System ◽  
Chaotic Systems ◽  
Lorenz System ◽  
Design Procedure ◽  
Sampling Period ◽  
Feedback Gain ◽  
Sampled Data ◽  
Lyapunov Approach ◽  
And Performance ◽  
Data Controller

This paper proposes a linear sampled-data controller for the stabilization of chaotic system. The system stabilization and performance issues will be investigated. Stability conditions will be derived based on the Lyapunov approach. The findings of the maximum sampling period and the feedback gain of controller, and the optimization of system performance will be formulated as a generalized eigenvalue minimization problem. Based on the analysis result, a stable linear sampled-data controller can be realized systematically to stabilize a chaotic system. An example of stabilizing a Lorenz system will be given to illustrate the design procedure and effectiveness of the proposed approach.

TEMPORAL QUANTUM CHAOS

1999 ◽  
Vol 13 (18) ◽  
pp. 2361-2369 ◽  
Author(s):  
R. AURICH ◽  
F. STEINER
Keyword(s):  
Quantum Chaos ◽  
Chaotic Systems ◽  
Quantum Systems ◽  
Time Behavior ◽  
Classical Dynamics ◽  
Long Time Behavior ◽  
Initial State ◽  
Numerical Tests ◽  
Weyl Sum ◽  
Long Time

We study the long-time behavior of bound quantum systems whose classical dynamics is chaotic and put forward two conjectures. Conjecture A states that the autocorrelation function C(t)=<Ψ(0)|Ψ(t)> of a delocalized initial state |Ψ(0)> shows characteristic fluctuations, which we identify with a universal signature of temporal quantum chaos. For example, for the (appropriately normalized) value distribution of S~|C(t)| we predict the distribution P(S)=(π/2)Se-πS2/4. Conjecture B gives the best possible upper bound for a generalized Weyl sum and is related to the extremely large recurrence times in temporal quantum chaos. Numerical tests carried out for numerous chaotic systems confirm nicely the two conjectures and thus provide strong evidence for temporal quantum chaos.

scholarly journals The Diagnostic Value and Performance Evaluation of Five Serological Tests for the Detection ofTreponema pallidum

2014 ◽  
Vol 28 (3) ◽  
pp. 204-209 ◽  
Author(s):  
Can Liu ◽  
Qishui Ou ◽  
Huijuan Chen ◽  
Jing Chen ◽  
Sheng Lin ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Diagnostic Value ◽  
Serological Tests ◽  
And Performance
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