scholarly journals Toward the Reconstruction of Substorm‐Related Dynamical Pattern of the Radiowave Auroral Absorption

Space Weather ◽  
2020 ◽  
Vol 18 (3) ◽  
Author(s):  
V. A. Sergeev ◽  
M. A. Shukhtina ◽  
N. A. Stepanov ◽  
D. D. Rogov ◽  
A. V. Nikolaev ◽  
...  
Keyword(s):  
2021 ◽  
Vol 2119 (1) ◽  
pp. 012079
Author(s):  
I P Starodubtseva ◽  
A N Pavlenko

Abstract The results of computational experiments simulating the triggering of the quench front propagation on the superheated vertically oriented metal plates are presented. The plates are quenched by a gravitationally flowing down liquid nitrogen film. The temperature of the test samples at the beginning of the process was higher than the critical temperature and the Leidenfrost temperature, which means that direct long-term liquid-solid contact is impossible. For this reason, the front is initially motionless. As a result of numerical simulation, a dynamic pattern of the quench front propagation on a high-temperature surface was obtained. Analysis of the results allowed to find the realistic values of heat sink into the cooling medium, as well as the parameters of the local temperature disturbance, its spatial extent and amplitude, at which the conditions are created for triggering the process of quench front propagation on the high-temperature surface. Direct comparison of the numerical simulations results with experimental data on the velocity, geometry of the quench front and on the dynamical pattern of the process confirmed the reliability of the results obtained.


1986 ◽  
pp. 67-75 ◽  
Author(s):  
Ryuji Takaki ◽  
Nobuo Yoshiyasu ◽  
Yoji Arai ◽  
Ken Adachi

Author(s):  
Justin Q Anderson ◽  
Praveen Janantha ◽  
Diego Alcala ◽  
Mingzhong Wu ◽  
Lincoln D Carr

Abstract We report the clean experimental realization of cubic-quintic complex Ginzburg-Landau physics in a single driven, damped system. Four numerically predicted categories of complex dynamical behavior and pattern formation are identified for bright and dark solitary waves propagating around an active magnetic thin film-based feedback ring: (1) periodic breathing; (2) complex recurrence; (3) spontaneous spatial shifting; and (4) intermittency. These nontransient, long lifetime behaviors are observed in self-generated microwave spin wave envelopes circulating within a dispersive, nonlinear yttrium iron garnet waveguide. The waveguide is operated in a ring geometry in which the net losses are directly compensated for via linear amplification on each round trip (of the order of 100~ns). These behaviors exhibit periods ranging from tens to thousands of round trip times (of the order of $\mu$s) and are stable for 1000s of periods (of the order of~ms). We present 10 observations of these dynamical behaviors which span the experimentally accessible ranges of attractive cubic nonlinearity, dispersion, and external field strength that support the self-generation of backward volume spin waves in a four-wave-mixing dominant regime. Three-wave splitting is not explicitly forbidden and is treated as an additional source of nonlinear losses. All observed behaviors are robust over wide parameter regimes, making them promising for technological applications. We present ten experimental observations which span all categories of dynamical behavior previously theoretically predicted to be observable. This represents a complete experimental verification of the cubic-quintic complex Ginzburg-Landau equation as a model for the study of fundamental, complex nonlinear dynamics for driven, damped waves evolving in nonlinear, dispersive systems. The reported dynamical pattern formation of self-generated dark solitary waves in attractive nonlinearity without external sources or potentials, however, is entirely novel and is presented for both the periodic breather and complex recurrence behaviors.


2020 ◽  
Vol 16 (1) ◽  
pp. 48-51
Author(s):  
T.M. Kostiuk ◽  
A.A. Kaniura ◽  
N. Lytovchenko

Relevance. Treatment of the temporo-mandibular joint (TMJ) dysfunctions still stays an urgent issue of modern stomatology. Its significance is predisposed for its high incidence and annual increase in patients’ referrals as well as diversity of it clinical manifestations, complexity of diagnosis and treatment, variability of clinical pattern, which requires a multi-disciplinary approach. According to Ukrainian and foreign authors, the TMJ pathologies take up the third place after caries and parodontal diseases, being diagnosed in 20 % of children and almost 87 % of adults. The share of patients with the TMJ dysfunction increases every year. The 79 % are represented with the intra-capsular disorders of the temporo-mandibular joints. The study was necessitated by the fact that there is still no single agreement in the treatment methods and definite treatment protocols regarding the intracapsular TMJ disorders. Objectives: analysis of efficiency of the TMJ intracapsular disorders patients’ treatment using the pathogenetically rationalized conservative and mini-invasive surgical methods. Methods and materials. The study includes the data of 38 patients with complaints of the TMJ region pain and the TMJ dysfunction. All patients were examined according to the common protocol. According to the disorder stage, the patients were administered either the conservative treatment course using the treatment tray on the mandible or maxilla, with the subsequent orthopedic or prosthetic treatment, or the splint therapy with subsequent surgical intervention. Results. Having analyzed the dynamical pattern of the treatment outcomes within the study, it has been detected that the surgical injection correction of the TMJ disorders was effective in all examined patients. To provide for the long-term steady treatment outcome the prosthetic-orthopedic rehabilitation measures were indicated, aimed at preserving the correct occlusion relation. Conclusion. The method of hyaluronic acid preparations injection into the TMJ cavity as a stage of the TMJ dysfunction therapy has proven its effectiveness in all the examined patients. In order to achieve the long-term steady result, the patients were recommended prosthetic-orthopedic rehabilitation for producing and supporting the occlusion relation.


Paleobiology ◽  
1986 ◽  
Vol 12 (4) ◽  
pp. 343-354 ◽  
Author(s):  
Russell Lande

Recent theoretical results demonstrate that a phenotypic version of Wright's shifting balance theory generates the dynamical pattern of punctuated equilibria. Thus, classical mechanisms of random genetic drift and selection for multiple adaptive peaks produce geologically long periods of relative stasis interrupted occasionally by very brief intervals of rapid change. A simple extension of this theory is made here to encompass developmental constraints between quantitative characters, manifested as phenotypic and genetic correlations between characters. Developmental constraints do not qualitatively alter the dynamical pattern of phenotypic evolution produced by selection and random genetic drift. A quantitative definition of stasis is proposed, based on a common taxonomic practice for recognizing subspecies. From this it is concluded that stasis is not the rule for quantitative measurements of detailed sequences for fossil species throughout most of their existence. Instead, periods of relative stasis are interspersed with gradual fluctuating trends, short intervals of rapid change, and discontinuities of subspecific magnitude.


2010 ◽  
Vol 4 (1) ◽  
pp. 48 ◽  
Author(s):  
Guillermo Rodrigo ◽  
Javier Carrera ◽  
Santiago F Elena ◽  
Alfonso Jaramillo

2012 ◽  
Vol 546-547 ◽  
pp. 182-187
Author(s):  
Wei Hua Liu ◽  
Yu Bin Gao

This paper proposes the basic concept of dynamical pattern recognition and introduces the implementation theories based on probability statistics .Based on the theory of the Discrete Hidden Markov Models (DHMM), the scalar quantization method of vibration spectrum vector of rotary machine is proposed, and then the fault diagnosis method based on DHMM is designed. The experiment of run-up process of rotor machine is made to verify the effect of the new fault diagnosis method.


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