1,246 research outputs found

    Quantum Oscillations of Elastic Moduli and Softening of Phonon Modes in Metals

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    In this paper we present a theoretical analysis of the effect of magnetostriction on quantum oscillations of elastic constants in metals under strong magnetic fields. It is shown that at low temperatures a significant softening of some acoustic modes could occur near peaks of quantum oscillations of the electron density of states (DOS) at the Fermi surface (FS). This effect is caused by a magnetic instability of a special kind, and it can give rise to a lattice instability. We also show that the most favorable conditions for this instability to be revealed occur in metals whose Fermi surfaces include nearly cylindrical segments.Comment: 5 pages, 1 figur

    Formação da teoria verbocêntrica da sentença no final do século XIX - segundo terço do século XX

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    The development of some provisions of the verbocentric theory of sentence covers the article. The interdisciplinary nature of the theory is proved, since it is realized at the intersection of lexicology, semantics, morphology, word formation and syntax. The provisions of the verbocentric theory in the works of Russian and foreign scientists of the late XIX - second third of the XX century are analyzed. The main approaches to determining the role of the Russian verb in the structure of the sentence are revealed. According to the first approach, the subject is the top of the sentence. According to the second approach, the subject and predicate are equal members of the sentence. According to the third approach, there is no equality between the subject and the predicate, since the verb in the sentence occupies a dominant position.El desarrollo de algunas disposiciones de la teoría verbocéntrica de la oración cubre el artículo. La naturaleza interdisciplinaria de la teoría está demostrada, ya que se realiza en la intersección de lexicología, semántica, morfología, formación de palabras y sintaxis. Se analizan las disposiciones de la teoría verbocéntrica en los trabajos de científicos rusos y extranjeros de finales del siglo XIX - segundo tercio del siglo XX. Se revelan los principales enfoques para determinar el papel del verbo ruso en la estructura de la oración. Según el primer enfoque, el sujeto es la parte superior de la oración. De acuerdo con el segundo enfoque, el sujeto y el predicado son miembros iguales de la oración. Según el tercer enfoque, no hay igualdad entre el sujeto y el predicado, ya que el verbo en la oración ocupa una posición dominante.O desenvolvimento de algumas disposições da teoria verbocêntrica da sentença abrange o artigo. A natureza interdisciplinar da teoria é comprovada, uma vez que é realizada na intersecção entre lexicologia, semântica, morfologia, formação de palavras e sintaxe. As disposições da teoria verbocêntrica nas obras de cientistas russos e estrangeiros do final do século XIX - segundo terço do século XX são analisadas. As principais abordagens para determinar o papel do verbo russo na estrutura da sentença são reveladas. De acordo com a primeira abordagem, o assunto é o topo da frase. De acordo com a segunda abordagem, o sujeito e o predicado são membros iguais da sentença. De acordo com a terceira abordagem, não há igualdade entre o sujeito e o predicado, uma vez que o verbo na frase ocupa uma posição dominante

    On the Theory of Quantum Oscillations of the Elastic Moduli in Layered Conductors

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    In this paper we study theoretically how the local geometry of the Fermi surface (FS) of a layered conductor can affect quantum oscillations in the thermodynamic observables. We introduce a concrete model of the FS of a layered conductor. The model permits us to analyze the characteristic features of quantum oscillatory phenomena in these materials which occure due to local anomalies of the Gaussian curvature of the FS. Our analysis takes into account strong interaction among quasiparticles and we study the effect of this interaction within the framework of Fermi-liquid theory. We show that the Fermi-liquid interaction strongly affects the density of states of quasiparticles (DOS) on the FS. As a result DOS can have singularities near the peaks of its oscillations in a strong magnetic field. These singularities can be significantly strengthened when the FS of the layered conductor is locally flattened. This can lead to magnetic and lattice instabilities of a special kind which are considered in the final part of the work.Comment: 11 pages, 2 figures, minor changes in the title are made, published versio

    THE DEVELOPMENT OF LOGICAL THINKING IN JUNIOR STUDENTS THROUGH PROJECT-BASED LEARNING

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    El artículo da una nueva mirada al método de desarrollo del pensamiento lógico en alumnos de tercer año basado en la correlación entre el modelo original y el que hace posible, a diferencia de los métodos tradicionales, desarrollar el pensamiento del habla, las estructuras intelectuales y las operaciones lógicas de los alumnos de manera más efectiva. . Con la ayuda de los enfoques epistemológico, de actividad sistémica y de entorno, se determina una estrategia para desarrollar el pensamiento lógico de los alumnos a través del aprendizaje basado en proyectos que se basa en la correlación entre el modelo original y el original. Asegura el desarrollo efectivo de a) la actividad intelectual de los escolares b) el pensamiento c) la memoria lógica. El estudio demuestra la efectividad de la tecnología presentada, lo que implica 1) sumergirse en el proyecto, así como especificar sus metas y objetivos; 2) organizar y planificar las actividades de los alumnos; 3) resolver las etapas principales del proyecto; 4) llevar a cabo el proyecto y su presentación; 5) evaluar los resultados. Con base en los datos de la investigación, se destacaron los siguientes criterios: análisis, síntesis, comparación, clasificación, generalización y algunos otros criterios que permitieron determinar tres niveles del desarrollo del fenómeno en cuestión. Nuestro método proporciona una mejora significativa de los resultados de la investigación y garantiza la formación de actividades de investigación, informativas, regulatorias y analíticas de aprendizaje universal (ULA). La evaluación de la efectividad y validez del método propuesto se corrobora mediante cálculos para el criterio de Fisher (criterio φ *). Los resultados comparativos de la investigación antes y después del experimento a alto nivel son 3.564. Los valores empíricos obtenidos de φ * están en el área de significancia. H0 se rechaza (el eje de significancia = 1.64–2.31). Por lo tanto, el método en cuestión tiene un grave impacto en el desarrollo del pensamiento lógico a través del aprendizaje basado en proyectos de alumnos menores.O artigo analisa o método de desenvolver o raciocínio lógico em alunos juniores com base na correlação entre o original e o modelo e possibilita, diferentemente dos métodos tradicionais, desenvolver o raciocínio, estruturas intelectuais e operações lógicas dos alunos de maneira mais eficaz. Com o auxílio das abordagens epistemológicas, de atividade sistêmica e do meio, é determinada uma estratégia para o desenvolvimento do pensamento lógico dos alunos por meio da aprendizagem baseada em projetos, baseada na correlação entre o original e o modelo. Garante o desenvolvimento efetivo de a) atividade intelectual das crianças em idade escolar b) pensamento c) memória lógica. O estudo comprova a eficácia da tecnologia apresentada, que implica 1) imersão no projeto, além de especificar suas metas e objetivos; 2) organização e planejamento das atividades dos alunos; 3) elaboração das principais etapas do projeto; 4) realização do projeto e sua apresentação; 5) avaliando os resultados. Com base nos dados da pesquisa, foram destacados os seguintes critérios: análise, síntese, comparação, classificação, generalização e outros critérios que permitiram determinar três níveis de desenvolvimento do fenômeno em questão. Nosso método fornece uma melhoria significativa dos resultados da pesquisa e garante a formação de atividades de aprendizagem universais (ULAs) informativas, regulatórias e analíticas. A avaliação da eficácia e validade do método proposto é corroborada por cálculos para o critério de Fisher (critério φ *). Os resultados comparativos da pesquisa antes e após o experimento em alto nível são 3.564. Os valores empíricos obtidos de φ * estão na área de significância. H0 é rejeitado (o eixo de significância = 1.64-2.31). Assim, o método em questão tem um sério impacto no desenvolvimento do pensamento lógico através da aprendizagem baseada em projetos de alunos juniores.The article takes a new look at the method of developing logical thinking in junior students based on the correlation between the original and the model and making it possible, unlike traditional methods, to develop students’ speech thinking, intellectual structures, and logical operations more effectively. With the aid of the epistemological, systemic-activity, and milieu approaches, a strategy for developing students’ logical thinking through project-based learning that is premised on the correlation between the original and the model is determined. It ensures the effective development of a) schoolchildren’s intellectual activity b) thinking c) logical memory. The study proves the effectiveness of the presented technology, that implies 1) immersing in the project as well as specifying its goals and objectives; 2) organizing and planning students’ activities; 3) working out the main stages of the project; 4) carrying out the project and its presentation; 5) evaluating the results. Based on the research data, the following criteria were singled out analysis, synthesis, comparison, classification, generalization, and some other criteria, which allowed determining three levels of the development of the phenomenon in question. Our method provides for a significant improvement of the results of the research and ensures the formation of research, informational, regulatory, and analytical universal learning activities (ULAs). The assessment of the effectiveness and validity of the proposed method are corroborated by calculations for the Fisher’s criterion (φ*-criterion). The comparative results of the research before and after the experiment at the high level are 3.564. The obtained empirical values of φ * are in the area of significance. H0 is rejected (the significance axis = 1.64–2.31). Thus, the method in question has a serious impact on the development of logical thinking through project-based learning of junior students

    Transfer of 0-order coherence matrix along spin-1/2 chain

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    In this work, we study transfer of coherence matrices along spin-1/2 chains of various length. Unlike higher order coherence matrices, 0-order coherence matrix can be perfectly transferred if its elements are properly fixed. In certain cases, to provide the perfect transfer, an extended receiver together with optimized its unitary transformation has to be included into the protocol. In this work, the asymptotic perfectly transferable 0-order coherence matrix for an infinitely long chain is considered and deviation of a perfectly transferred state from this asymptotic state is studied as a function of the chain length for various sizes of the extended receiver. The problem of arbitrary parameter transfer via the nondiagonal elements of the 0-order coherence matrix is also considered and optimized using the unitary transformation of the extended receiver.Comment: 32 pages, 5 figure

    MODERN APPROACHES TO INTELLECTUAL PROPERTY COST ESTIMATION UNDER CRISIS CONDITIONS FROM CONSUMER QUALITY PRESERVATION VIEWPOINT

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    Various intellectual property (IP) estimation approaches and innovations in this field are discussed. Problem situations and «bottlenecks» in the economic mechanism of transformation of innovations into useful products and services are defined. Main international IP evaluation methods are described, particular attention being paid to «Quick Inside» program defined as latest generation global expert system. IP income and expense evaluation methods used in domestic practice are discussed. Possibility of using the Black-Scholes optional model to estimate costs of non-material assets is studied
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