143,304 research outputs found
PERIODIZAÇÃO DE MATVEEV PARA O FUTEBOL: UMA REVISÃO
No full textEl objetivo de la revisión fue explicar cómo estructurar la periodización tradicional de Matveev para el fútbol profesional. Matveev desarrolló su periodización desde los años 40 hasta los 70, pero esta concepción no es apta para el deporte actual. Sin embargo, el autor de la revisión hizo algunas adaptaciones a esta periodización y fue posible aplicarla en el fútbol. En conclusión, actualizar la periodización de Matveev es importante para el deporte contemporáneoO objetivo da revisão foi explicar em como estruturar a periodização tradicional de Matveev para o futebol profissional. Matveev desenvolveu a sua periodização nos anos 40 a 70, mas essa concepção não está adequada para o esporte da atualidade. Porém, o autor da revisão fez algumas adaptações nessa periodização e foi possível aplicar no futebol. Em conclusão, atualizar a periodização de Matveev é importante para o esporte contemporâneo
ESTRUTURANDO O MICROCICLO DA PERIODIZAÇÃO DE MATVEEV
No full textEl objetivo de la revisión era explicar los períodos de la periodización tradicional de Matveev. Para Matveev, cuando un entrenador estructura una periodización el intenta resolver los problemas de entrenamiento de la modalidad que se está entrenando a través de sus conocimientos teóricos y prácticos para desarrollar al máximo los deportistas durante toda la temporada. Los períodos de la periodización de Matveev (preparatoria, competitiva y de transición) tienen fases de adaptaciones fisiológicas según la organización pedagógica de la carga de entrenamiento que deben relacionarse según el calendario competitivo. Por tanto, periodizar el entrenamiento consiste en dividir la temporada en varios momentos de preparación que se denominan periodos para que el deportista alcance el pico de su forma deportiva en la competición durante el periodo competitivo o para lograr un alto desempeño en la disputa. En conclusión, los períodos de Matveev merecen durar según las necesidades del deporte actual para que el deportista logre una forma deportiva adecuada en la competición.
O objetivo da revisão foi explicar como estruturar o microciclo da periodização de Matveev. Os anos 40 e 50 os soviéticos começaram a dedicar muitos estudos sobre a carga de treino para elaborar melhor os microciclos. Durante esse período Matveev utilizou o conteúdo da Síndrome de Adaptação Geral para entender o efeito agudo da carga de treino no atleta e utilizou a supercompensação para explicar o efeito crônico da carga de treino. O primeiro procedimento para estruturar o microciclo é saber o período que se encontra a periodização para o treinador escolher o adequado mesociclo. Os mesociclos ocorrem em algumas semanas e possuem certas características que agrupam determinados microciclos que estão de acordo com as suas diretrizes de treino. O microciclo é onde o treinador elabora as cargas de treino ao longo da temporada, cada um desses microciclos possuem características que merecem ser utilizados em um determinado período da periodização de Matveev. Em conclusão, elaborar um microciclo é um conteúdo complexo que requer adequado conhecimento científico para o esportista atingir o pico da forma esportiva
A short proof of the Gaillard-Matveev theorem based on shape invariance arguments
No full textInternational audienceWe propose a simple alternative proof of the Wronskian representation formula obtained by Gaillard and Matveev for the trigonometric Darboux-Poschl-Teller (TDPT) potentials. It rests on the use of singular Darboux-Backlund transformations applied to the free particle system combined to the shape invariance properties of the TDPT
Thermoacoustic Instabilities in the Rijke Tube: Experiments and Modeling
No full textThermoacoustic instability can appear in thermal devices when unsteady heat release is coupled with pressure perturbations. This effect results in excitation of eigen acoustic modes of the system. These instabilities are important in various technical applications, for instance, in rocket motors and thermoacoustic engines.
A Rijke tube, representing a resonator with a mean flow and a concentrated heat source, is a convenient system for studying the fundamental physics of thermoacoustic instabilities. At certain values of the main system parameters, a loud sound is generated through a process similar to that in real-world devices prone to thermoacoustic instability. Rijke devices have been extensively employed for research purposes. The current work is intended to overcome the serious deficiencies of previous investigations with regard to estimating experimental errors and the influence of parameter variation on the results. Also, part of the objective here is to account for temperature field non-uniformity and to interpret nonlinear phenomena. The major goals of this study are to deliver accurate experimental results for the transition to instability and the scope and nature of the excited regimes, and to develop a theory that explains and predicts the effects observed.
An electrically heated, horizontally oriented, Rijke tube is used for the experimental study of transition to instability. The stability boundary is quantified as a function of major system parameters with measured uncertainties for the data collected. Hysteresis in the stability boundary is observed for certain operating regimes of the Rijke tube.
An innovative theory is developed for modeling the Rijke oscillations. First, linear theory, incorporating thermal analysis that accurately determines the properties of the modes responsible for the transition to instability, is used to predict the stability boundary. Then, a nonlinear extension of the theory is derived by introducing a hypothesis for a special form of the nonlinear heat transfer function. This nonlinear modeling is shown to predict the hysteresis phenomenon and the limit cycles observed during the tests.
A new, reduced-order modeling approach for combustion instabilities in systems with vortex shedding is derived using the developed analytical framework. A hypothesis for the vortex detachment criterion is introduced, and a kicked oscillator model is applied to produce nonlinear results characteristic for unstable combustion systems.
The experimental system and the mathematical model, developed in this work for the Rijke tube, are recommended for preliminary design and analysis of real-world thermal devices, where thermoacoustic instability is a concern.</p
Variations of selective separability II: Discrete sets and the influence of convergence and maximality
No full textAbstractA space X is called selectively separable (R-separable) if for every sequence of dense subspaces (Dn:n∈ω) one can pick finite (respectively, one-point) subsets Fn⊂Dn such that ⋃n∈ωFn is dense in X. These properties are much stronger than separability, but are equivalent to it in the presence of certain convergence properties. For example, we show that every Hausdorff separable radial space is R-separable and note that neither separable sequential nor separable Whyburn spaces have to be selectively separable. A space is called d-separable if it has a dense σ-discrete subspace. We call a space X D-separable if for every sequence of dense subspaces (Dn:n∈ω) one can pick discrete subsets Fn⊂Dn such that ⋃n∈ωFn is dense in X. Although d-separable spaces are often also D-separable (this is the case, for example, with linearly ordered d-separable or stratifiable spaces), we offer three examples of countable non-D-separable spaces. It is known that d-separability is preserved by arbitrary products, and that for every X, the power Xd(X) is d-separable. We show that D-separability is not preserved even by finite products, and that for every infinite X, the power X2d(X) is not D-separable. However, for every X there is a Y such that X×Y is D-separable. Finally, we discuss selective and D-separability in the presence of maximality. For example, we show that (assuming d=c) there exists a maximal regular countable selectively separable space, and that (in ZFC) every maximal countable space is D-separable (while some of those are not selectively separable). However, no maximal space satisfies the natural game-theoretic strengthening of D-separability
Módulo de gestión de factura electrónica para la tramitación con la administración de la India
No full text[ES] El Good and Services Tax Counsil (GSTC), entidad responsable de la gestión de tributos de la República de la India, aprobó la introducción escalonada del sistema de declaración de facturas electrónicas entre empresas B2B en el sistema Good and Service Tax (GST). Esto implica la obligación de presentar al gobierno las facturas B2B emitidas para que este las certifique antes de que lleguen a su destinatario (el comprador o el facturado).
Como consecuencia de esto, una empresa cliente de EDICOM, se ha visto en la necesidad de declarar sus facturas mediante el nuevo sistema de factura electrónica India, para ello, ha contratado un proyecto para la implementación de conexiones y mapeados para poder transformar las facturas en su formato hacia el formato propuesto por el GST y enviarlas al mismo a través de EDICOM.
Para EDICOM es un proyecto piloto, puesto que es el primer proyecto de facturación electrónica en India que se realiza, por lo tanto, no está estandarizado. Además, cuenta con diversos flujos y mapeados, debido a los requisitos del cliente, lo que le añade complejidad a la instalación.[EN] The Good and Services Tax Counsil (GSTC), the entity responsible for the management of taxes in the Republic of India, approved the gradual introduction of the electronic invoice declaration system between B2B companies in the Good and Service Tax (GST) system. This implies the obligation to present the issued B2B invoices to the government so that it can certify them before they reach their recipient (the buyer or the invoiced person).
As a consequence of this, an EDICOM client company has seen the need to declare its invoices using the new Indian electronic invoice system, for this, it has signed a project for the implementation of connections and mappings to be able to transform the invoices into their format towards the format proposed by the GST and send them to it through EDICOM.
For EDICOM it is a pilot project, since it is the first electronic invoicing project in India to be carried out, therefore, it is not standardized, in addition, it has different flows and mappings, due to the client's requirements, which adds complexity to the installation.Fedchuk Matveev, I. (2021). Módulo de gestión de factura electrónica para la tramitación con la administración de la India. Universitat Politècnica de València. https://riunet.upv.es/handle/10251/173945TFG
Spatially-localized time dependent solutions including turbulence and their interactions in 2D Kolmogorov flow
No full textIn 2D Kolmogorov flow in small aspect ratio domains, spatially-localized solutions such as kink, traveling or time-dependent kink-antikink pars coexist. However, the conservation of the flow rate in the y direction strongly restrict combination of localized solutions and their positioning. We find that by adding a homogeneous flow U y their positioning is controlled and each of localized solutions including a spatially-localized chaos is isolated. Numerical results suggest that these isolated solutions can be elements constructing a whole flow
Characteristics of overlap region in high-Reynolds number turbulent channel flow
No full textDirect numerical simulation of the fully developed turbulent channel flows have been carried out at the Reynolds number based on the friction velocity and the channel half width, 2000, 4000 and 8000. A hybrid 10th order accurate finite difference scheme in the stream and spanwise directions, and a second-order scheme in the wall-normal direction is adapted as the spatial discretization method. We observed the plateau profiles in the indicator function corresponded to the von Karman constant. Furthermore, second peak of streamwise pre-multiplied spectra were appeared in the same wall normal height, 300 < y+ < 600, in case of Re = 4000. Nevertheless, the effects of the lager than the channel half height scale on the streamwise turbulent intensity are fixed contributions without dependence on Reynolds number. These results suggested that the new streamwise vortexes are formed between buffer layer and outer layer with increasing of Reynolds number
La 'circunstancia' de 'Herederos y Pretendientes
No full textIn June 2010, the Ortega y Gasset Foundation hosted a Conference about the “Spanish Philosophical Transition” in order to debate the book of Francisco Vázquez, La filosofía española. Herederos y Pretendientes. Una lectura sociológica (1963-1990), recently published. This paper is the author’s response to criticism raised in the Conference and to published reviews received by this book. First, the author summarized the argument of Herederos y pretendientes. Secondly he responds and takes into account the most important objections against the book’s hypothesis and methodology. Finally the author evaluates the favorable judgments received by the book and suggests the limits of the historian’s task.Fundación Ortega y Gasset-Marañó
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