Algebraic Model for scattering in three-s-cluster systems. I. Theoretical Background

A framework to calculate two-particle matrix elements for fully antisymmetrized three-cluster configurations is presented. The theory is developed for a scattering situation described in terms of the Algebraic Model. This means that the nuclear many-particle state and its asymptotic behaviour are expanded in terms of oscillator states of the intra-cluster coordinates. The Generating Function technique is used to optimize the calculation of matrix elements. In order to derive the dynamical equations, a multichannel version of the Algebraic Model is presented.Comment: 20 pages, 1 postscript figure, submitted to Phys. Rev.

Peculiar properties of the cluster-cluster interaction induced by the Pauli exclusion principle

Role of the Pauli principle in the formation of both the discrete spectrum and multi-channel states of the binary nuclear systems composed of clusters is studied in the Algebraic Version of the resonating-group method. Solutions of the Hill-Wheeler equations in the discrete representation of a complete basis of the Pauli-allowed states are discussed for 4He+n, 3H+3H, and 4He+4He binary systems. An exact treatment of the antisymmetrization effects are shown to result in either an effective repulsion of the clusters, or their effective attraction. It also yields a change in the intensity of the centrifugal potential. Both factors significantly affect the scattering phase behavior. Special attention is paid to the multi-channel cluster structure 6He+6He as well as to the difficulties arising in the case when the two clustering configurations, 6He+6He and 4He+8He, are taken into account simultaneously. In the latter case the Pauli principle, even in the absence of a potential energy of the cluster-cluster interaction, leads to the inelastic processes and secures an existence of both the bound state and resonance in the 12Be compound nucleus.Comment: 17 pages, 14 figures, 1 table; submitted to Phys.Rev.C Keywords: light neutron-rich nuclei, cluster model

Técnica, princípios e características de avaliação da eficiência econômica da construção e reconstrução de rodovias

Efficiency assessment technique of capital investments in construction and reconstruction of highways is described in this article. Despite the degree of readiness of the methodical device, specialized construction norms of VSN 21-83 focused on implementation of such assessment were not widely adopted in view of the difficulties arising in the course of collecting basic data, their reliability and quality. The present article contains the characteristics of the grouped components and evaluation criteria, in particular, the description of settlement indicators in a section of the intra-transport, extra-transport and social and economic effects resulting from capital investments in linear objects of road infrastructure. On a concrete example the assessment procedure and calculations of summary economic indicators for groups and for the project in general is shown. What shows is a possibility of application of rather difficult technique and its efficiency as scientific tool of complex assessment for the solution of applied tasks in road construction. And use of departmental construction norms in combination with the dynamic methods of assessment based on the analysis of cash flows can increase substantially scientific validity of administrative decisions and quality of investment projects in the field of development of road infrastructure.En este artículo se describe la técnica de evaluación de la eficiencia de las inversiones de capital en la construcción y reconstrucción de carreteras. A pesar del grado de preparación del dispositivo metódico, las normas de construcción especializadas de VSN 21-83 enfocadas en la implementación de dicha evaluación no se adoptaron ampliamente en vista de las dificultades que surgen en el curso de la recopilación de datos básicos, su confiabilidad y calidad. El presente artículo contiene las características de los componentes agrupados y los criterios de evaluación, en particular, la descripción de los indicadores de asentamiento en una sección del transporte interno, transporte extra y los efectos sociales y económicos resultantes de las inversiones de capital en objetos lineales de infraestructura vial. En un ejemplo concreto se muestra el procedimiento de evaluación y los cálculos de indicadores económicos resumidos para grupos y para el proyecto en general. Lo que muestra es una posibilidad de aplicación de una técnica bastante difícil y su eficiencia como herramienta científica de evaluación compleja para la solución de tareas aplicadas en la construcción de carreteras. Y el uso de normas de construcción departamentales en combinación con los métodos dinámicos de evaluación basados en el análisis de flujos de efectivo puede aumentar sustancialmente la validez científica de las decisiones administrativas y la calidad de los proyectos de inversión en el campo del desarrollo de infraestructura vial.A técnica de avaliação de eficiência de investimentos de capital em construção e reconstrução de rodovias é descrita neste artigo. Apesar do grau de prontidão do dispositivo metódico, normas de construção especializadas do VSN 21-83 voltadas para a implementação de tal avaliação não foram amplamente adotadas em vista das dificuldades surgidas no decorrer da coleta de dados básicos, sua confiabilidade e qualidade. O presente artigo contém as características dos componentes agrupados e critérios de avaliação, em particular, a descrição dos indicadores de liquidação em uma seção dos efeitos intra-transporte, extra-transporte e sociais e econômicos resultantes de investimentos de capital em objetos lineares de infraestrutura rodoviária. Em um exemplo concreto, o procedimento de avaliação e os cálculos de indicadores econômicos resumidos para grupos e para o projeto em geral são mostrados. O que mostra é uma possibilidade de aplicação de técnica bastante difícil e sua eficiência como ferramenta científica de avaliação complexa para a solução de tarefas aplicadas na construção de estradas. E o uso de normas de construção departamental em combinação com os métodos dinâmicos de avaliação com base na análise dos fluxos de caixa pode aumentar substancialmente a validade científica das decisões administrativas e da qualidade dos projetos de investimento no campo do desenvolvimento da infraestrutura rodoviária

Estimating the cutting force when skiving with a radius cutter

The paper considers the method of determining the components of the cutting force under cutting completed with a radius cutter. The authors provide the design of the experimental study. The authors provide the data on the cutting force change in the process of turning with a radius cutter according to the cutting edge inclination, cutting depth and supply obtained experimentally and calculated analytically. The paper also provides the results of experimental work approximation and theoretical error checking related to experimental data

Measuring microwave quantum states: tomogram and moments

Two measurable characteristics of microwave one-mode photon states are discussed: a rotated quadrature distribution (tomogram) and normally/antinormally ordered moments of photon creation and annihilation operators. Extraction of these characteristics from amplified microwave signal is presented. Relations between the tomogram and the moments are found and can be used as a cross check of experiments. Formalism of the ordered moments is developed. The state purity and generalized uncertainty relations are considered in terms of moments. Unitary and non-unitary time evolution of moments is obtained in the form of linear differential equations in contrast to partial differential equations for quasidistributions. Time evolution is specified for the cases of a harmonic oscillator and a damped harmonic oscillator, which describe noiseless and decoherence processes, respectively.Comment: 10 pages, 1 figure, to appear in Phys. Rev.

Cutting Edge Geometry Effect on Plastic Deformation of Titanium Alloy

The paper presents experimental studies of ОТ4 titanium alloy machining with cutting edges of various geometry parameters. Experiments were performed at a low speed by the scheme of free cutting. Intensity of plastic shear strain was set for defining of cutting edge geometry effect on machining. Images of chip formed are shown. Estimation of strain magnitude was accomplished with digital image correlation method. Effect of rake angle and cutting edge angle has been studied. Depth of deformed layer and the area of the plastic strain is determine. Results showed that increasing the angle of the cutting edge inclination results in a change the mechanism of chip formation

Fractal-like aggregates: Relation between morphology and physical properties

A number of modern technological applications require a detailed calculation of the physical properties of aggregated aerosol particles. For example, in probing soot aerosols by the method called laser-induced incandescence (LII), the soot clusters are suddenly heated by a short, powerful laser pulse and then cool down to the temperature of the carrier gas. LII sizing is based on rigorous calculation of the soot aggregate heat-up and cooling and involves prediction of laser light absorption and energy and mass transfer between aggregated particles and the ambient gas. This paper describes results of numerical simulations of the mass or energy transfer between the gas and fractal-like aggregates of N spherical particles in either the free-molecular or continuum regime, as well as the light scattering properties of random fractal-like aggregates, based on Rayleigh–Debye–Gans (RDG) theory. The aggregate geometries are generated numerically using specially developed algorithms allowing “tuning” of the fractal dimension and prefactor values. Our results are presented in the form of easily applicable scaling laws, with special attention paid to relations between the aggregate gyration radius and the effective radius describing various transport processes between the aggregates and the carrier gas