Congrès International d'Architecture Moderne

About: Congrès International d'Architecture Moderne is a based out in . It is known for research contribution in the topics: Boundary value problem & Jet (fluid). The organization has 393 authors who have published 403 publications receiving 4104 citations.

Internal Shocks in Supersonic Flows past the Contours of Optimal Bodies and Nozzles

Abstract: The problems of designing the contours of two-dimensional and axisymmetric bodies of minimum wave drag and maximum-thrust nozzles, such that flow past them can contain internal shocks, are considered within the ideal (inviscid and non-heat-conducting) gas model. These shocks may occur in flows past internal breaks in the optimal contours or on intersection of characteristics of the same family proceeding from these breaks. The submerged shocks occurring in the latter case are named internal, if their initial points lie within the domain of determinacy of the flowed-over optimal contour region. Further downstream the domain of determinacy is bounded by the characteristic coming to the end point of this contour. The internal submerged shocks can appear, when the optimal contour includes an interval of an isobaric streamline. The appearance of internal breaks in the optimal contours is possible due to the reflection of the pressure waves induced by them from the bow shock (for body noses) or, as might be expected, from tangential discontinuities (for afterbodies). In the case of supersonic freestreams having a tangential discontinuity the search for optimal two-dimensional afterbodies with an internal concave break flowed-over with an oblique shock is performed using the direct method with the representation of the required contours by the Bernstein—Bezier curves, a genetic algorithm, and a rapid and accurate marching scheme for calculating steady supersonic flows. While the optimal two-dimensional afterbodies with a convex internal break designed earlier using the general method of Lagrange multipliers could be reliably reproduced using the above-mentioned method, the expected optimal configurations with a concave break and an internal shock were not found. Instead, optimal contours with centered compression and expansion waves with the common focus on a tangential discontinuity and an “external” oblique shock proceeding from it were discovered. Then the new “discontinuous shock-free” solutions were constructed in the exact formulation, within the framework of the method of indefinite control contours and the method of characteristics. The solutions are generalized to include the contours of the afterbodies of revolution and supersonic parts of nozzles. In the case of a uniform freestream the flow past optimal afterbodies never includes internal shocks.

On accelerated mhd flows of second grade fluid in a porous medium and rotating frame

Abstract: The rotating magnetohydrodynamics (MHD) flow of a second grade fluid due to an accelerated plate is examined. Modified Darcy’s law is used to formulate the physical problem in a porous space. Two cases of interest namely constant and variable accelerated MHD flows are addressed. Fourier sine transform technique is adopted to solve analytically the resulting problems. Finally, from the exact solutions the implied effects of emerging flow parameters on the velocity field are displayed and discussed.

Rendimiento y valor nutritivo de nuevas leguminosas anuales como cultivo de invierno en rotaciones forrajeras intensivas en galicia

Abstract: Se presentan resultados de produccion y valor nutritivo observados en un ensayo realizado en la zona atlantica de Galicia donde se evaluaron seis especies de leguminosas anuales sembradas en otono como cultivo monofto. Las especies fueron: trebol encarnado ( Trifolium incarnatum L . ); trebol migueliano ( T. michelianum Savi); trebol persa ( T .resupinatum L . ) ssp . resupinatum y ssp. majus ; trebol vesiculoso ( T. vesiculosum Savi . ) y serradella ( Ornithopus sativus Brot . ). La cosecha se realizo en seis fechas diferentes a intervalos de dos semanas desde mediados de marzo, con un segundo corte a las seis semanas. En el primer ciclo la produccion de materia seca (MS) por hectarea vario ampliamente entre especies (de 3389 a 6685 kg MS ha-1) y entre fechas de corte (de 1571 a 8591 kg MS ha-1). En el segundo aprovechamiento, todas las especies mostraron capacidad de rebrote hasta la tercera fecha de corte del primer ciclo, con una produccion media de 3087 kg MS ha-1. Las calibraciones NIRS desarrolladas para estimar el valor nutricional de estas especies mostraron un buen poder predictivo. Los valores medios de digestibilidad in vitro de la materia organica (DMOIV, %) y de proteina bruta (PB, %MS) para el primer y segundo ciclo fueron, respectivamente, 73,0% y 72,3% para DMOIV y 17,9% y 19,0% para PB, indicando una excelente calidad nutricional para estas especies, si bien el contenido medio de materia seca fue muy bajo, alrededor del 12% de media para el primer y segundo cortes. El descenso de calidad en el primer ciclo fue mas acusado a partir de mediados de abril, por lo que esta fecha podria ser adecuada para ensilar, proporcionando un forraje de alta digestibilidad y rico en proteina. Sin embargo, el bajo contenido en MS de estas especies puede comprometer la obtencion de una buena calidad de fermentacion del ensilado.

Associations between STR autosomal markers and longevity

Abstract: Life span is a complex and multifactorial trait, which is shaped by genetic, epigenetic, environmental, and stochastic factors The possibility that highly hypervariable short tandem repeats (STRs) associated with longevity has been largely explored by comparing the genotypic pools of long lived and younger individuals, but results so far have been contradictory In view of these contradictory findings, the present study aims to investigate whether HUMTHO1 and HUMCSF1PO STRs, previously associated with longevity, exert a role as a modulator of life expectancy, as well as to assess the extent to which other autosomal STR markers are associated with human longevity in population from northern Spain To that end, 21 autosomal microsatellite markers have been studied in 304 nonagenarian individuals (more than 90 years old) and 516 younger controls of European descent Our results do not confirm the association found in previous studies between longevity and THO1 and CSF1PO loci However, significant association between longevity and autosomal STR markers D12S391, D22S1045, and DS441 was observed Even more, when we compared allelic frequency distribution of the 21 STR markers between cases and controls, we found that 6 out of the 21 STRs studied showed different allelic frequencies, thus suggesting that the genomic portrait of the human longevity is far complex and probably shaped by a high number of genomic loci