Relevant bibliographies by topics / Columnas de gravas

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Academic literature on the topic 'Columnas de gravas'

Author: Grafiati
Published: 4 June 2021
Last updated: 18 February 2022

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Journal articles on the topic "Columnas de gravas"

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Aguiar, Roberto, and Fernando Del Castillo. "PRIMEROS TRABAJOS EN EL REFORZAMIENTO SÍSMICO DE PARQUEADERO DE LA ULEAM." Revista Internacional de Ingeniería de Estructuras 24, no. 1 (March 8, 2019): 39. http://dx.doi.org/10.24133/riie.v24i1.1166.

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La causa principal del daño, durante el terremoto del 16 de abril de 2016 (M=7.8), en el parqueadero de la Universidad Laica Eloy Alfaro de Manabí, fue la presencia de columna corta en el pórtico central que tiene losas a diferentes desniveles. En este artículo se describe este problema y la forma cómo se va a reforzar la estructura.La estructura fue diseñada con el criterio de viga fuerte-columna débil, razón por la cual se produjeron fisuras en las columnas las mismas que a simple vista no parecían graves pero por el volumen de resina epóxica que se utilizó, el daño fue considerable. El daño generó pérdida de resistencia en el hormigón de las columnas, el mismo que fue restituido mediante la colocación de fibra de carbono. De esta forma se reparó las columnas y en este artículo se indica como se va a reforzar la estructura, para que tenga una mayor capacidad sísmica.
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Castro, Jorge. "Avances en el diseño y cálculo de columnas de grava. Parte II: Grupos de columnas y consolidación secundaria." Informes de la Construcción 73, no. 561 (March 16, 2021): e371. http://dx.doi.org/10.3989/ic.71912.

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Este artículo recoge algunos aspectos teóricos recientes relativos a columnas de grava que pueden resultar útiles para su diseño y cálculo. En esta segunda parte, se recogen comentarios sobre la estimación del diámetro de las columnas, sobre grupos de columnas, y sobre la problemática específica causada por asientos de consolidación secundaria. Se muestra que el número de columnas mientras se mantenga el área de sustitución bajo la cimentación no tiene influencia en el valor del asiento y que la posición de las columnas dentro de la cimentación tiene una influencia muy pequeña. La longitud crítica de las columnas es del orden de 2 veces el ancho o diámetro de la cimentación superficial. También se muestra la menor eficacia de las columnas de grava en la reducción de asientos por consolidación secundaria. Cuando se estime que los asientos por consolidación secundaria pueden ser importantes, lo recomendable es realizar una sobrecarga.
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Splendiani, G., S. Passalacqua, G. Barbera, A. Sturniolo, S. Costanzi, E. Bartoccioni, and C. U. Casciani. "Myasthenia Gravis (MG) Treatment with Immunoadsorbent Columns." Biomaterials, Artificial Cells and Immobilization Biotechnology 19, no. 1 (January 1991): 255–65. http://dx.doi.org/10.3109/10731199109117831.

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Castro, Jorge. "Avances en el diseño y cálculo de columnas de grava. Parte I: Ejemplo de cálculo." Informes de la Construcción 72, no. 560 (November 23, 2020): e362. http://dx.doi.org/10.3989/ic.71911.

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Este artículo recoge algunos aspectos teóricos recientes relativos a columnas de grava que pueden resultar útiles para su diseño y cálculo. En esta primera parte, se presenta un ejemplo de cálculo de reducción de asientos y aceleración de tiempos de consolidación utilizando diferentes métodos. De forma general, los métodos de cálculo utilizados han proporcionado resultados adecuados si se tienen en cuenta las limitaciones y posibilidades de cada una de ellos. Los métodos semi-empíricos son sencillos porque proporcionan la reducción de asiento en función principalmente del factor de sustitución. Los métodos analíticos desarrollados recientemente basados en la celda unidad permiten considerar la influencia de otros parámetros, pero normalmente la información disponible respecto a su valor es limitada. Finalmente, los cálculos por elementos finitos proporcionan una gran flexibilidad en el análisis, pero es necesaria una adecuada comprensión de las hipótesis, modelos constitutivos y parámetros empleados.
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Pták, Jan. "Changes of plasma proteins after immunoadsorption using Ig-Adsopak columns in patients with myasthenia gravis." Transfusion and Apheresis Science 30, no. 2 (April 2004): 125–29. http://dx.doi.org/10.1016/j.transci.2003.11.005.

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Splendiani, G., S. Cipriani, S. Passalacqua, A. Sturniolo, S. Costanzi, P. Fulignati, E. Staffolani, and C. U. Casciani. "Plasmaperfusion on Triptophan Columns Can Improve the Clinical Outcome of Patients Affected with Myasthenia Gravis." Artificial Cells, Blood Substitutes, and Biotechnology 31, no. 1 (January 2003): 69–79. http://dx.doi.org/10.1081/bio-120018004.

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Antozzi, Carlo, Renato Mantegazza, Dionisio Peluchetti, Fulvio Baggi, Paola Romagnoli, Maurizio Marconi, Angelo Vescoyv, and Ferdinando Cornelio. "Use of immunoadsorbent columns for antiacetylcholine receptor antibody removal from plasma of myasthenia gravis patients." Plasma Therapy and Transfusion Technology 9, no. 1 (January 1988): 73–75. http://dx.doi.org/10.1016/0278-6222(88)90036-8.

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CARO LOPERA, MIGUEL ANGEL, ZAHYRA CAMARGO MARTÍNEZ, and GRACIELA URIBE ÁLVAREZ. "La arquitectura textual del carnaval en las columnas irónicas de Daniel Samper Ospina." Cuadernos de Lingüística Hispánica, no. 32 (June 20, 2018): 41. http://dx.doi.org/10.19053/0121053x.n32.2018.8117.

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Este artículo de reflexión, derivado de una tesis sobre la enseñanza de la comprensión de textos argumentativos irónicos, aborda, a la luz del interaccionismo sociodiscursivo, la posible arquitectura textual carnavalizada que se desprende de un corpus de 117 columnas de opinión de Daniel Samper Ospina publicadas entre 2014 y 2016 en la Revista Semana (Colombia). Desde un interés hermenéutico y perspectivas pragmalingüísticas para el estudio de la ironía verbal, se identifican rasgos de carnaval bajtiniano en los tres niveles de la infraestructura textual (gracias al juego con la dispositio argumentativa tradicional y al travestimiento de géneros), la textualización (mediante inversiones a los principios neogriceanos de Levinson, según el Grupo de la Ironía, Alicante, Lengua Española, Griale) y la responsabilidad enunciativa (como fruto de la inserción de enunciadores absurdos que enmascaran la función locutor). Esto refuerza la concepción de la ironía como dispositivo textual carnavalizante del decir, sus modos, sus voces y sus estructuras.
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García, Celso, and Ramón J. Batalla Villanueva. "Cálculo de la tensión de corte a partir de los perfiles de velocidad en un río de gravas." Ingeniería del agua 7, no. 3 (September 30, 2000): 237. http://dx.doi.org/10.4995/ia.2000.2846.

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A partir de 6 perfiles de velocidad, realizados en una sección transversal de un río de gravas con caudal bajo, se ha calculado la tensión de corte aplicando la ley del muro. Las medidas de velocidad se representan en función del logaritmo de la altura a la que fueron realizadas. A partir de la ecuación de una recta de regresión se calculan los principales parámetros hidráulicos: velocidad de corte, tensión de corte y altura de la rugosidad. Los resultados demuestran que las medidas realizadas para cada perfil dentro de la capa logarítmica de la columna de agua (20 %) son las que permiten un cálculo correcto de la tensión de corte que realiza el flujo sobre las partículas. La tensión media de corte, calculada mediante la ecuación de du Boys, sobrestima en más de 5 veces el valor obtenido en la tensión de corte deducida a partir de las velocidades. Se recomienda, siempre que sea posible, utilizar las medidas de velocidad dentro de la capa logarítmica para el posterior cálculo de la tensión de corte, ya que estos valores reflejan la fuerza que realiza el flujo sobre las partículas del lecho de manera más precisa que los deducidos a partir de la ecuación de du Boys.
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Avanzi, G., F. Cepparone, R. Lombardo, G. Di Pietro, and G. Marconi. "Plasma exchange, tryptophan and protein A columns adsorption in the treatment of a severe myasthenia gravis patient." Transfusion Science 14, no. 4 (October 1993): 369–70. http://dx.doi.org/10.1016/s0955-3886(05)80009-8.

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Dissertations / Theses on the topic "Columnas de gravas"

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Mendoza, Acosta Diego Fernando, and Perez Andrea Stefania Paitan. "Columnas de grava para reducir los asentamientos de una estructura hospitalaria cimentada sobre arcilla de alta plasticidad en San Ignacio, Cajamarca." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/654636.

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Los suelos blandos son los más comunes en necesitar algún tipo de mejoramiento o refuerzo, y la elección de la técnica dependerá de las características del suelo, costo, tiempo y otros factores importantes. Entre estos métodos, se encuentra la técnica de la columna de grava, la cual permite acelerar la consolidación de los suelos blandos, mejorar la capacidad portante, reducir los asentamientos, y por tanto las características geotécnicas del suelo. La presente tesis consistirá en analizar y estudiar la metodología de columnas de grava como una técnica de mejora para un suelo de tipo arcilloso. Para ello, se aplicará la técnica en un caso de estudio para una obra ubicada en Cajamarca y se analizarán los asentamientos con y sin columna de grava. Se utilizarán los ensayos de laboratorio necesarios para la obtención de los parámetros geotécnicos del suelo en estudio. A partir de estos datos y utilizando el método de Priebe, se determinarán las dimensiones de las columnas de grava y posteriormente se calculará el asentamiento por consolidación primaria. El resultado obtenido permite ver favorablemente la reducción de los asentamientos.
Soft soils are the most common in needing some type of improvement or reinforcement, and the choice of technique will depend on the characteristics of the soil, cost, time and other important factors. Among these methods is the gravel column technique, which allows to accelerate the consolidation of soft soils, reduce settlements, improve bearing capacity and therefore the geotechnical characteristics of the soil. This thesis will consist of analyzing and studying the gravel column methodology as an improvement technique for a clay-type soil. For this, the technique will be applied in a case study for a work located in Cajamarca and settlements with and without a gravel column will be analyzed. The necessary laboratory tests will be used to obtain the geotechnical parameters of the soil under study. From these data and using the Priebe method, the dimensions of the gravel columns will be determined and then the settlement by primary consolidation will be calculated. The result obtained allows a favorable view of the reduction of settlements.
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Salazar, Izquierdo Rubén Louredes. "Mejoramiento de suelos arenosos mediante el uso de columnas de grava." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2014. http://tesis.pucp.edu.pe/repositorio/handle/123456789/8129.

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El mejoramiento de los suelos utilizando columnas de grava es un procedimiento constructivo desarrollado desde el siglo XIX en Europa debido al incremento en la demanda de suelos adecuados para la construcción de infraestructura que sirviera para el desarrollo de una sociedad. Nuestro país posee gran diversidad de suelos, muchos de los cuales, especialmente en la costa, están conformados por depósitos de arena que no servirían como base de cimentación para la construcción de edificaciones debido a su baja densidad relativa. El mejoramiento de suelos arenosos mediante el uso de columnas de grava es un método de mejora del terreno no muy difundido en nuestro país pese a la gran cantidad de beneficios que obtenemos de su uso, entre los cuales tenemos el incremento de la densidad relativa del terreno, reducción de asentamientos, aceleración del proceso de consolidación, disminución del riesgo de licuefacción, entre otros. Basándonos en este problema, este proyecto de tesis iniciará dando una vista general de los métodos de mejoramiento de suelo utilizados en la actualidad, enfocándonos principalmente en el uso de columnas de grava, se describirán sus características generales, el procedimiento de diseño de las columnas y los diferentes procesos constructivos que se utilizan. Se identificarán también los tipos de suelo en los cuales se obtienen resultados óptimos, se describirán los beneficios adicionales que ofrecen las columnas de grava en comparación con otros métodos de mejoramiento y los ensayos de verificación que se realizan para comprobar la eficiencia del mejoramiento; posteriormente se presentarán los resultados obtenidos en el suelo luego de haber realizado un mejoramiento con columnas de grava y se compararán estos resultados con las características del suelo natural con la finalidad de determinar el grado de mejoramiento alcanzado. Por último se realizará el diseño de una cimentación superficial analizando las zapatas por corte y asentamiento, se realizará el diseño de una cimentación profunda basada en la resistencia a la penetración de los suelos y se analizarán los resultados obtenidos.
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Reyes, Morales Anthony Hans. "Mejoramiento de suelos granulares mediante el uso de columnas de grava." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2020. http://hdl.handle.net/20.500.12404/17367.

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A lo largo de los años el uso común de solo cimentaciones superficiales y profundas como alternativa de estructuras de apoyo sobre el terreno ha limitado el uso óptimo de los recursos disponibles. Esto conlleva que en muchos casos se plantee la utilización de cimentaciones profundas, pilotes, en proyectos en lo que se puede aprovechar las condiciones geomecánicas del terreno y poder plantear una cimentación mucho más eficiente y efectiva. El método de columnas de grava es una alternativa de cimentación intermedia entre las dos antes mencionadas que consiste en mejorar las características resistentes y elásticas del suelo. El sistema se basa en tomar estas propiedades como ángulo de fricción interna, cohesión y módulo de deformación para incorporarle la mejora a través de las columnas de grava, las cuales poseen características conocidas y controladas. El objetivo es obtener un suelo con propiedades geotécnicas más favorables que las iniciales como resultado de la suma de las condiciones del suelo sin mejora y el aporte de las inclusiones. El presente estudio consiste en revisar los métodos de diseño y constructivos de las distintas metodologías de tratamiento de terreno, en especial las columnas de grava. Esto para desarrollar el diseño de esta metodología de mejora a través de un caso práctico y comparar las ventajas de esta sobre el diseño de una cimentación profunda mediante pilotes. En el caso práctico se realiza el diseño de la cimentación en estudio a partir de los resultados de las investigaciones geotécnicas proporcionadas, las cuales permiten determinar los parámetros resistentes y deformacionales del terreno natural. Es así como se pasa a desarrollar y presentar los resultados del diseño, los cuales muestran que la alternativa de mejoramiento de terreno resulta mucho más eficiente en términos económicos e ingenieriles, ya que se obtienen parámetros geotécnicos favorables que cumplen con las solicitaciones de la estructura a proyectar que en un inicio eran insuficientes, las características del suelo, para los requerimientos del proyecto.
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Castro, González Jorge. "Análisis teórico de la consolidación y deformación alrededor de columnas de grava." Doctoral thesis, Universidad de Cantabria, 2008. http://hdl.handle.net/10803/10604.

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Las columnas de grava constituyen uno de los métodos habituales de mejora del terreno para la cimentación de terraplenes o estructuras en suelos blandos. Mejoran la capacidad portante y la estabilidad al deslizamiento y reducen el valor del asiento y el tiempo que tarda en producirse.Las columnas acortan el camino de drenaje de una forma similar a los drenes verticales. Por ello, suelen emplearse las mismas soluciones para estudiar su consolidación radial. Sin embargo, las columnas son mucho más rígidas que los drenes y soportan una parte importante de la carga. En esta tesis se ha desarrollado una solución analítica que permite incluir la interacción radial y vertical entre el suelo y la columna en el estudio de su consolidación radial. La solución permite obtener las tensiones y las deformaciones en cualquier instante a través de una sencilla hoja de cálculo.Se presentan también los resultados de la instrumentación realizada en dos obras reales en las que el terreno fue mejorado con columnas de grava.
Stone columns, either by the vibro-replacement or vibro-displacement methods, are one of the most common improvement techniques for foundation of embankments or structures on soft soils. The main effects usually considered with respect to the untreated ground conditions are: improvement of bearing capacity, reduction of total and differential settlements, acceleration of consolidation, improvement of the stability of embankments and natural slopes, and reduction of liquefaction potential.In this thesis, a new closed-form solution that includes the radial and vertical interaction between soil and column has been developed. The solution gives all the stresses and displacements at any time by means of a simple spreadsheet.The instrumentation of two different field sites where the ground was improved with stone columns is shown and analysed.
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Miranda, Manzanares Marina. "Influencia de la densidad y del confinamiento con geotextil en columnas de grava." Doctoral thesis, Universidad de Cantabria, 2014. http://hdl.handle.net/10803/288207.

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El tratamiento con columnas de grava es uno de los métodos de mejora del terreno empleados habitualmente para la cimentación de terraplenes o estructuras sobre suelos blandos. El estudio realizado en esta Tesis Doctoral se centra en analizar: - La influencia de la densidad de la grava de la columna - El empleo de columnas ensacadas con geotextil. El análisis de la influencia de la densidad de la grava se ha realizado mediante ensayos realizados en laboratorio en modelo reducido con dos densidades de la grava diferentes y varias áreas de sustitución. Los ensayos se realizaron en una célula edométrica Rowe-Barden instrumentada en la que se ha estudiado el comportamiento de una rebanada de una celda unidad. El análisis de los resultados se ha centrado en el reparto tensional suelo-columna, la reducción de asientos y la disipación de presiones intersticiales. Para completar el estudio se han realizado simulaciones numéricas de los ensayos, además los resultados experimentales se han comparado con los obtenidos del empleo de las soluciones analíticas más relevantes. El estudio de columnas ensacadas se ha llevado a cabo de forma análoga mediante ensayos a escala reducida en el laboratorio. Los resultados se han contrastado con los obtenidos de simulaciones numéricas y de las soluciones analíticas más representativas.
Stone columns are a soft soil improvement method usually employed in embankments and structures foundations under soft soils. The study carried out in this PhD Thesis is focused on the analysis of: - The influence of the density of the gravel in the column and - The encasement of stone columns with geotextile. With the aim of study the influence of the density of the gravel, laboratory small scale tests have been carried out with two different densities and several areas replacement ratios. These tests have been developed in a Rowe-Barden cell where the behavior of a unit cell is analyzed. The cell employed is instrumented in order to measure total and pore pressures as well as displacements. The results obtained were analyzed from the point of soil-column stress ratio, settlement reduction and dissipation of pore pressures. In order to complement the study, numerical analyses simulating the laboratory tests have been executed employing several constitutive models. Their results have been compared with the experimental ones. Finally, experimental results have been compared with the ones obtained from the most relevant analytical solutions. The study of encased stone columns has been carried out in a similar way as the mentioned previously for the analysis of the density. Small scale test similar to those presented before but this time using two different geotextiles. This time, as well as before, experimental results have been compared with the ones from the numerical simulations and the ones obtained from the most important analytical solutions.
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Cimentada, Hernández Ana Isabel. "Análisis experimental en modelo reducido de la consolidación radial y deformación de un suelo blando mejorado con columnas de grava." Doctoral thesis, Universidad de Cantabria, 2009. http://hdl.handle.net/10803/10605.

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El estudio del proceso de consolidación radial alrededor de las columna de grava y de la interacción suelo-columna suele realizarse analizando una celda unitaria formada por una columna de grava central y el área de terreno circundante, sobre la cual ejerce su acción de mejora. En esta tesis doctoral se ha modelizado a escala reducida una celda unidad para analizar la transferencia de carga entre la columna y el terreno y el proceso de consolidación que se produce alrededor de la columna, para condiciones de carga vertical rígida.Se han realizado ensayos con columnas de dos diámetros distintos, con el fin de estudiar también la influencia del área de suelo blando reemplazada por la columna. Se presentan los resultados obtenidos en cada ensayo, su interpretación, y la comparación con soluciones teóricas existentes. Todo ello tanto para el análisis de la consolidación radial como para el comportamiento deformacional del conjunto suelo-columna.
The analysis of the radial consolidation process around the column and the column-soil interaction is based on the study of a unit cell approach, which consists of a central column of gravel and the surrounding soil. In this thesis, a unit cell in small scale has been reproduced with the aim of analyzing load transfer between soil and column, settlement reduction and radial consolidation process that happen when a rigid vertical load is applied on surface.Tests with two different geometries are carried out.From the results, some conclusions related to consolidation process, stress concentration factor and settlement reduction have been obtained for each testing geometry.The influence of the replacement area has been studied comparing the results of both geometries.Finally, the results are presented and interpreted using some existing analytical solutions related to consolidation process and stone columns deformation.
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Falla, Rufasto Percy Carlos. "Propuesta de Mejoramiento de suelos licuables mediante el uso de columnas de grava en áreas portuarias – Puerto del Callao." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/655860.

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La presente tesis estudia como eliminar el potencial de licuefacción del suelo en el Puerto del Callao, específicamente en el Muelle 5E, mediante el uso de columnas de grava. Donde el análisis del potencial de licuefacción se hace mediante el método de SEED&IDRISS modificado, se realizaron los cálculos con un sismo de grado 8.5 en la escala de Richter. Los datos del terreno fueron hallados mediante los ensayos de penetración estándar (SPT). Para dar solución al problema de licuefacción del suelo, se aplicaron columnas de grava, el diseño de estas se calculó mediante el método de SEED&BOOKER, estas permiten densificar el terreno y drenar el agua existente, disminuir los asientos totales y diferencial, y aumenta la capacidad portante del suelo. Finalmente, la tesis tiene como fin poder demostrar mediante la comparación del calculo de potencial de licuefacción antes y después de la aplicación de las columnas de grava, así como mediante el numero de golpes del ensayo SPT se puede ver las mejora del terreno.
This thesis studies how to eliminate the potential for soil liquefaction in the Port of Callao, specifically in Pier 5E, through the use of gravel columns. Where the analysis of the liquefaction potential is done by the modified SEED & IDRISS method, the calculations were made with an earthquake of grade 8.5 on the Richter scale. Terrain data were found by standard penetration tests (SPT). To solve the soil liquefaction problem, gravel columns were applied, the design of these was calculated using the SEED & BOOKER method, these allow to densify the land and drain the existing water, reduce the total and differential settlements, and increase the capacity. bearing from the ground. Finally, the thesis aims to be able to demonstrate by comparing the calculation of liquefaction potential before and after the application of the gravel columns, as well as by means of the number of hits of the SPT test, the improvement of the terrain can be seen.
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Hassanabadi, Massoud. "Grain Refinement of Commercial EC Grade 1070 Aluminium Alloy for Electrical Application." Thesis, KTH, Materialvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-163402.

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The aluminium alloys for electrical conductivity applications are generally not grain refinedsince the addition of grain refiners drops the electrical conductivity by introducing impuritiesinto the melt. Non-grain refined aluminium may lead to bar fracture and cracks during themetalworking process. The present study focuses to find an optimum balance between the grain refiner addition andthe electrical conductivity of commercial EC grade 1070 aluminium alloy for electricalapplication. In order to reach this goal, the electrical conductivity and the macrostructure ofcommercial EC grade 1070 aluminium (commercial pure aluminium) have been studiedunder a series of controlled lab scale trails. Specific addition levels of different grain refiners(TiBloy, Al-5Ti-1B, Al-3Ti-0.15C, and Al-3Ti-1B) were added to the metal melt and sampleswere taken at specific time intervals. The collected samples were sectioned, ground andmacro-etched. Thereafter, the macrostructure was analysed by the use of a digital camera andthe electrical conductivity was measured at temperature. The obtained result was expressed asa percentage of the International Annealed Copper Standard (IACS %). The macro-structuralanalysis showed that TiBloy, Al-5Ti-1B, and Al-3Ti-1B, with the maximum addition level of0.1%, cannot grin refine commercial pure aluminium. However, at higher grain refiner levelsthe number of columnar grains increased and their size decreased. The Al-3Ti-0.15C master alloy, with the same addition level as the once chosen for the othergrain refiners (up to 0.1%), showed significantly better grain refining. By the addition of0.1% of this grain refiner the macrostructure became very equiaxed already after 30 minutesof grain refiner addition. The fading of the Al-3Ti-0.15 master alloy was, however, observedfor samples with a long holding time. Nevertheless, by maximum addition level (0.1%) and a90 minutes holding time the macrostructure remained as equiaxed grains. The electrical conductivity results showed that none of the applied grain refiners (TiBloy, Al-5Ti-1B, Al-3Ti-0.15C, and Al-3Ti-1B), with the maximum addition level of 0.1%, decreasedthe electrical conductivity of commercial pure aluminium.
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Prins, Heinrich Johann. "The effect of autogenous gas tungsten arc welding parameters on the solidification structure of two ferritic stainless steels." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/79303.

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Ferritic stainless steel is typically used in the automotive industry to fabricate welded tube that is plastically deformed for flanging, bending and necking. The effect of welding parameters during autogenous gastungsten arc welding (GTAW) of thin sheet on the weld metal structure and tensile properties were determined. Two grades of ferritic stainless steels, a titanium-containing Grade 441 and a titanium-free molybdenum-containing Grade 436, were used as base metal. Statistical analysis was used to determine the influence of welding parameters on the microstructure of autogenous GTAW welds. The results of Grade 441 indicated that the welding speed and peak welding current had a statistically significant influence on the amount of equiaxed grains that formed. For Grade 436, the same welding parameters (welding speed and peak welding current) had a statistically significant influence on the grain size of the weld metal grains. The ductility of a tensile test coupon machined parallel to the weld direction, for both base metal grades, was unaffected by the welding parameters or the weld metal microstructure. The elongation was determined by the amount of weld metal in the gauge area of a tensile coupon. The titanium content of the base material seems to have the most significant effect on the formation of equiaxed grains.
Dissertation (MEng)--University of Pretoria, 2019.
Metallurgical Engineering
MEng
Unrestricted
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Freire, Alexandre da Silva. "Empacotamento de bicliques em grafos bipartidos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-26112012-161435/.

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Nesta tese, estudamos o problema de Empacotamento de Bicliques. Um biclique é um grafo bipartido completo. No problema de Empacotamento de Bicliques são dados um inteiro k e um grafo bipartido G e deseja-se encontrar um conjunto de k bicliques, subgrafos de G, dois a dois disjuntos nos vértices, tal que a quantidade total de arestas dos bicliques escolhidos seja máxima. No caso em que k=1, temos o problema de Biclique máximo. Esses dois problemas possuem aplicações na área de Bioinformática. Mantemos neste trabalho um enfoque prático, no sentido de que nosso interesse é resolver instâncias desses dois problemas com tamanho razoavelmente grande. Para isso, utilizamos técnicas de Programação Linear Inteira. Para avaliar os métodos propostos aqui, mostramos resultados de experimentos computacionais feitos com instâncias vindas de aplicações e também com instâncias geradas aleatoriamente.
In this thesis, we study the Biclique Packing problem. A biclique is a complete bipartite graph. In the Biclique Packing problem we are given an integer k and a bipartite graph G and we want to find a set of k vertex disjoint bicliques of G, such that the total number of biclique\'s edges is maximum. When k=1, we have the Maximum Biclique problem. These two problems have applications in Bioinformatics. In this work we keep a practical focus, in the sense that we are interested in solving large size instances of these problems. To tackle these problems, we use Integer Linear Programming techniques. In order to evaluate the methods proposed here, we show results of computational experiments carried out with practical application\'s instances and also with randomly generated ones.
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Books on the topic "Columnas de gravas"

1

Ganeri, Anita. The story of Columbus. New York: Dorling Kindersley Pub., 2001.

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Hessler, John W. Christopher Columbus Book of privileges: 1502, the claiming of a new world. Delray Beach, Florida: Levenger Press in association with the Library of Congress, Washington, D.C., 2014.

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I), Spain Sovereign (1479-1504 :. Ferdinand V. and Isabella. The book of privileges issued to Christopher Columbus by King Fernando and Queen Isabel, 1492-1502. Berkeley: University of California Press, 1996.

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Lyman, R. Lee. Graphing Culture Change in North American Archaeology. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198871156.001.0001.

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Documentation, analysis, and explanation of culture change have long been goals of archaeology. The earliest archaeological spindle graphs appeared in the 1880s and 1890s, but had no influence on subsequent archaeologists. Line graphs showing change in frequencies of specimens in each of several artifact types were used in the 1910s and 1920s. Seriograms or straight-sided spindles diagraming interpretations of culture change were published in the 1930s, but were seldom subsequently mimicked. Spindle graphs of centered and stacked columns of bars, each column representing a distinct artifact type, each bar the empirically documented relative frequency of specimens in an assemblage, were developed in the 1940s, became popular in the 1950s and 1960s, and are often used to illustrate culture change in textbooks published during the twentieth century. Graphs facilitate visual thinking, different graph types suggest different ontologies and theories of change, and particular techniques of parsing temporally continuous morphological variation of artifacts into types influence graph form. Line graphs, bar graphs, spindle diagrams, and phylogenetic trees of artifacts and cultures indicate archaeologists often mixed elements of Darwinian variational evolutionary change with elements of Midas-touch-like transformational change. Today there is minimal discussion of graph theory or graph grammar in both introductory archaeology textbooks and advanced texts, and elements of the two theories of evolution are often mixed. Culture has changed, and despite archaeology’s unique access to the totality of humankind’s cultural past, there is minimal discussion on graph theory, construction, and decipherment in the archaeological literature.
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Dunlop, Eileen. Tales of st Columba. Learning Links, 1992.

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Coffman, Elesha. “You Cannot Fool the Electronic Eye”. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190683528.003.0009.

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Billy Graham navigated the intersection of media and evangelism adeptly as he advanced his two great goals: the evangelization of the world, and the establishment of evangelicalism as a religious tradition. This chapter chronicles Graham’s media ventures, such as his Hour of Decision radio broadcasts, and illustrates how he used and was used by mainstream journalists, usually to mutual benefit. It argues that Graham was able to maintain a balance between savvy and slick because he was sincere in ways suited to the media-saturated culture of postwar America. His personal probity, remarked upon by journalists, helped. But Graham also found medium-specific ways to communicate authenticity, ranging from the chatty tone of his “My Answer” newspaper columns to the mixture of zoom and wide-angle shots in televised crusades. To achieve his goals in the second half of the twentieth century, Graham had to use media. To use media for good, he also had to use it well.
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Stitzer, Kim, and Marie Hablitzel. Draw Write Now, Book 2: Christopher Columbus, Autumn Harvest, Weather (Draw-Write-Now). Barker Creek Publishing, 1995.

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Ganeri, Anita, and Dk Publishing. DK Readers: The Story of Christopher Columbus (Level 2: Beginning to Read Alone). DK CHILDREN, 2001.

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Shaibani, Aziz. Pseudoneurologic Syndromes. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190661304.003.0022.

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The term functional has almost replaced psychogenic in the neuromuscular literature for two reasons. It implies a disturbance of function, not structural damage; therefore, it defies laboratory testing such as MRIS, electromyography (EMG), and nerve conduction study (NCS). It is convenient to draw a parallel to the patients between migraine and brain tumors, as both cause headache, but brain MRI is negative in the former without minimizing the suffering of the patient. It is a “software” and not a “hardware” problem. It avoids irritating the patient by misunderstanding the word psychogenic which to many means “madness.”The cause of this functional impairment may fall into one of the following categories:• Conversion reaction: conversion of psychological stress to physical symptoms. This may include paralysis, hemisensory or distal sensory loss, or conversion spasms. It affects younger age groups.• Somatization: chronic multiple physical and cognitive symptoms due to chronic stress. It affects older age groups.• Factions disorder: induced real physical symptoms due to the need to be cared for, such as injecting oneself with insulin to produce hypoglycemia.• Hypochondriasis: overconcern about body functions such as suspicion of ALS due to the presence of rare fasciclutations that are normal during stress and after ingestion of a large amount of coffee. Medical students in particular are targets for this disorder.The following points are to be made on this topic. FNMD should be diagnosed by neuromuscular specialists who are trained to recognize actual syndrome whether typical or atypical. Presentations that fall out of the recognition pattern of a neuromuscular specialist, after the investigations are negative, they should be considered as FNMDs. Sometimes serial examinations are useful to confirm this suspicion. Psychatrists or psychologists are to be consulted to formulate a plan to discover the underlying stress and to treat any associated psychiatric disorder or psychological aberration. Most patients think that they are stressed due to the illness and they fail to connect the neuromuscular manifestations and the underlying stress. They offer shop around due to lack of satisfaction, especially those with somatization disorders. Some patients learn how to imitate certain conditions well, and they can deceive health care professionals. EMG and NCS are invaluable in revealing FNMD. A normal needle EMG of a weak muscles mostly indicates a central etiology (organic or functional). Normal sensory responses of a severely numb limb mean that a lesion is preganglionic (like roots avulsion, CISP, etc.) or the cause is central (a doral column lesion or functional). Management of FNMD is difficult, and many patients end up being chronic cases that wander into clinics and hospitals seeking solutions and exhausting the health care system with unnecessary expenses.It is time for these disorders to be studied in detail and be classified and have criteria set for their diagnosis so that they will not remain diagnosed only by exclusion. This chapter will describe some examples of these disorders. A video clip can tell the story better than many pages of writing. Improvement of digital cameras and electronic media has improved the diagnosis of these conditions, and it is advisable that patients record some of their symptoms when they happen. It is not uncommon for some Neuromuscular disorders (NMDs), such as myasthenia gravis (MG), small fiber neuropathy, and CISP, to be diagnosed as functional due to the lack of solid physical findings during the time of the examination. Therefore, a neuromuscular evaluation is important before these disorders are labeled as such. Some patients have genuine NMDs, but the majority of their symptoms are related to what Joseph Marsden called “sickness behavior.” A patient with carpal tunnel syndrome (CTS) may unconsciously develop numbness of the entire side of the body because he thinks that he may have a stroke.
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Book chapters on the topic "Columnas de gravas"

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Presland, Rob, Alistair Boyce, and Engliang Chin. "Thorndon Container Wharf: Temporary Works for Recovery of Container Operations (New Zealand)." In Case Studies on Conservation and Seismic Strengthening/Retrofitting of Existing Structures, 127–44. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2020. http://dx.doi.org/10.2749/cs002.127.

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<p>The Thorndon Container Wharf sustained severe damage in the November 2016 M7.8 Kaikoura earthquake. Substantialworks, of a temporary nature, were required to restore thewharf for container handling operations. The temporary securing works included gravel columns within the reclamation fill and restraining and underpinning of the wharf. All of these works were designed and constructed over a 9-month period to provide a temporary facility for container handling operations for a period of up to 3 years. The temporary securingworks were required to secure the container cranes, maintain support to the wharf structure, and ensure the reclamation behind the wharf had sufficient strength to support lateral loads imposed by the restraining system. This was to enable container operations to recommence and to maintain business continuity, pending action on replacement or reinstatement of the container wharf. This paper outlines the development of the design of the temporary works to secure and return to operations a 125- m working length of wharf and reclamation.</p>
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Brown, Jill Dunlap, and Jana Schmidt. "Column 1 for Grades 2–5 *." In Matching Reading Data to Interventions, 34–40. Routledge, 2019. http://dx.doi.org/10.4324/9780429275234-4.

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Brown, Jill Dunlap, and Jana Schmidt. "Column 2 for Grades 2–5 *." In Matching Reading Data to Interventions, 41–46. Routledge, 2019. http://dx.doi.org/10.4324/9780429275234-5.

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Brown, Jill Dunlap, and Jana Schmidt. "Column 3 for Grades 2–5 *." In Matching Reading Data to Interventions, 47–54. Routledge, 2019. http://dx.doi.org/10.4324/9780429275234-6.

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Brown, Jill Dunlap, and Jana Schmidt. "Column 4 for Grades 2–5 *." In Matching Reading Data to Interventions, 55–58. Routledge, 2019. http://dx.doi.org/10.4324/9780429275234-7.

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"Spinal Column." In Gray's Clinical Neuroanatomy: The Anatomic Basis for Clinical Neuroscience, 111–16. Elsevier, 2011. http://dx.doi.org/10.1016/b978-1-4160-4705-6.00007-7.

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Morton, David A., Kerry D. Peterson, and Kurt H. Albertine. "Deep Back, Vertebral Column, and Suboccipital Region." In Gray's Dissection Guide for Human Anatomy, 23–36. Elsevier, 2007. http://dx.doi.org/10.1016/b978-0-443-06951-2.50009-x.

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Christiansen, Stacy, and Connie Manno. "Tables, Figures, and Multimedia." In AMA Manual of Style, 113–70. Oxford University Press, 2020. http://dx.doi.org/10.1093/jama/9780190246556.003.0004.

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The Tables, Figures, and Multimedia chapter of the 11th edition of the AMA Manual of Style begins with guidance on when to use tables vs figures or tables vs text. Descriptions of various table types (eg, matrix, box, sidebar, and other nontabular material) and examples of each illustrate advice on organization of information, use of footnotes, alignment, titles, column and row headings, and treatment of punctuation, abbreviations, and units of measure. Descriptions of assorted figures (statistical graphs, diagrams, maps, illustrations, and clinical imaging), each with examples, provide advice on scales, axis labels, and error bars, as well as titles and legends. New with this edition is sentence-style capitalization for table column headings and graph axis labels. Consent for identifiable patients is covered, and helpful guidelines for preparing both figures and tables are included. Detailed specifications on acceptable video and audio file formats, optimal video quality, and filming and copyright considerations complete the chapter.
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Raitz, Karl. "Heritage and Process." In Making Bourbon, 17–22. University Press of Kentucky, 2020. http://dx.doi.org/10.5810/kentucky/9780813178752.003.0002.

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American spirits distilling grew from European and colonial traditions and the age-old knowledge that grains could be milled into a fine meal, mixed with malted barley, and fermented and distilled into alcohol spirits. Traditional copper alembics, or pot stills, were augmented by innovative vertical column stills to increase production. Traditional lore often attributes Kentucky’s bourbon production to the presence of pure, iron-free limestone water. More likely, early distillers who wished to produce a superior, higher-quality whiskey than that made in the Corn Belt were responsible for Kentucky’s preeminence in the contemporary distilling industry.
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Gorman, Sara E., and Jack M. Gorman. "Introduction." In Denying to the Grave. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780199396603.003.0004.

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On October 8, 2014, Thomas Eric Duncan died in a Dallas hospital from Ebola virus infection. From the moment he was diagnosed with Ebola newspapers all over the country blared the news that the first case of Ebola in the United States had oc¬curred. Blame for his death was immediately assigned to the hospital that cared for him and to the U.S. Centers for Disease Control and Prevention (CDC). By the end of the month a total of four cases had developed in the United States: two in people— including Duncan— who acquired it in African countries where the disease was epidemic and two in nurses who cared for Duncan. Headlines about Ebola continued to dominate the pages of American newspapers throughout the month, warning of the risk we now faced of this deadly disease. These media reports were frightening and caused some people to wonder if it was safe to send their children to school or ride on public transportation— even if they lived miles from any of the four cases. “There are reports of kids being pulled out of schools and even some school closings,” reported Dean Baker in the Huffington Post. “People in many areas are not going to work and others are driving cars rather than taking mass transit because they fear catching Ebola from fellow passengers. There are also reports of people staying away from stores, restaurants, and other public places.” An elementary school in Maine suspended a teacher because she stayed in a hotel in Dallas that is 9.5 miles away from the hospital where two nurses contracted the virus. As Charles Blow put it in his New York Times column, “We aren’t battling a virus in this country as much as a mania, one whipped up by reactionary politicians and irresponsible media.” It turns out that Thomas Duncan was not the only person who died in the United States on October 8, 2014. If we extrapolate from national annual figures, we can say that on that day almost 7,000 people died in the United States.
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Conference papers on the topic "Columnas de gravas"

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Nanjo, Takanori, Toshikazu Miyashita, Shunji Kataoka, and Takuya Sato. "Study on Intermediate Support of Tall Columns for FPSO Topside Structures." In ASME 2016 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/pvp2016-63177.

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FPSO (Floating Production, Storage and Offloading) has become used increasingly for off-shore gas fields. Most tall pressure vessels such as columns installed in the FPSO are surrounded by topside structures. In general, columns in on-shore plants are supported only by bottom skirts; on the other hand, some of the tall columns on FPSO hulls require intermediate supports in addition to bottom skirts because of large accelerations they are subject to due to ship motion induced by wave loading. In this paper, the effects of the support were investigated considering acceleration distributions and structure deformation (drift), then the ideal elevation of the support was determined to minimize bending moment throughout the columns under the combined conditions. A dimensionless controlling parameter related to the acceleration, structure drift, and column properties was proposed and graphs (called N-Charts) were proposed to understand effects in reducing the maximum bending moment with respect to the elevation of the guide.
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Tonks, D. L., D. L. Paisley, P. D. Peralta, S. R. Greenfield, D. D. Byler, S. Luo, D. C. Swift, et al. "SPALLATION DAMAGE IN COPPER WITH COLUMNAR GRAINS." In SHOCK COMPRESSION OF CONDENSED MATTER - 2007: Proceedings of the Conference of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP, 2008. http://dx.doi.org/10.1063/1.2833164.

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Al-Abbas, Faisal M., Tariq A. Al-Ghamdi, and Stephen Liu. "Comparison of Solidification Behavior Between Underwater Wet Welding and Dry Welding." In ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49485.

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The solidification substructure, both mode and size, has influence on the mechanical properties of weld joints. Controlling the solidification substructure by obtaining finer grains will generally result in enhancement of the weld joint quality and properties. Thus, it is essential to understand how welding parameters including voltage, current and weld travel speed as well as the welding environment (air and water) affect the solidification substructure. This work presents the effects of welding parameters on columnar grain morphology for both wet and dry welds. Also it compares the solidification rate and columnar grain size (width and length) between the dry welds and wet welds. For fair comparison, the welding parameters of both dry welds and wet welds were maintained similar. The solidification rate of wet welds is faster than that for the dry welds. A maximum difference of 22% was observed at half distance from the fusion line to the weld centerline. For wet welds, the observations revealed that the average columnar grain width and length of wet welds decrease with increasing electrode angle and decreasing welding travel speed. On the other hand, the columnar grain width decreased with increasing welding current. Also, as the welding current increased the average columnar grain length increases. Dry welds differed from wet welds in that the columnar grain average length decreased as the welding current increases. Moreover, the wet weld columnar grains are finer than those found in the dry welds at low welding current, namely 110A and 120A, whereas the wet weld columnar grains are comparable or coarser at high welding current, e.g.130 A and 140A. Statistical analysis of the columnar grain aspect ratio data set using Student’s-t test resulted in low t-value, 0.329 for low current welds, while high t-value, 7.775, was obtained for the welds made at high welding current. Results revealed that the columnar grain morphology in wet welds and dry welds are statistically different at low welding current 110A while columnar grains in dry and wet welds are similar at high welding current 140A.
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Basawaraj, Janusz A. Starzyk, and Adrian Horzyk. "Lumped mini-column associative knowledge graphs." In 2017 IEEE Symposium Series on Computational Intelligence (SSCI). IEEE, 2017. http://dx.doi.org/10.1109/ssci.2017.8285413.

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Wołczyn´ski, Waldemar S., Edward Guzik, Wojciech Wajda, and Bogusz Kania. "Columnar → Equiaxed Structure Transition in Solidifying Rolls." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-23048.

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As the first step of simulation, a temperature field for solidifying cast steel and cast iron roll was created. The convection in the liquid is not comprised since in the first approximation, the convection does not influence the analysed occurrence of the C → E (columnar to equiaxed grains) transition in the roll. The obtained temperature field allows to study the dynamics of its behavior observed in the middle of the mould thickness. This midpoint of the mould thickness was treated as an operating point for the C → E transition. A full accumulation of the heat in the mould was postulated for the C → E transition. Thus, a plateau at the T(t) curve was observed at the midpoint. The range of the plateau existence tC ↔ tE corresponded to the incubation period, tCR ↔ tER that appeared before fully equiaxed grains formation. At the second step of simulation, the thermal gradients field was studied. Three ranges were distinguished: a/ for the formation of the columnar structure (the C–zone): (T˙≫0and(G|t&lt;tCR−G|t=tCR)≫0), b/ for the C → E transition (from columnar to fully equiaxed structure): (T˙≈0and(G|t=tCR−G|t=tER)≈0), c/ for the formation of the fully equiaxed structure (the E–zone): (T˙&lt;0and(G|t=tER−G|t&gt;tER)≈0). The columnar structure formation was significantly slowed down during incubation period. It resulted from a competition between columnar growth and equiaxed growth expected at that period of time. The (G|t=tCR − G|t=tER) ≈ 0) relationship was postulated to correspond well with the critical thermal gradient, Gcrit.. A simulation was performed for the cast steel and cast iron rolls solidifying as if in industrial condition. Since the incubation divides the roll into two zones (columnar and equiaxed) some experiments dealing with solidification were made on semi-industrial scale. A macrosegregation equation for both mentioned zones was formulated. It was based on a recent equation for redistribution after back-diffusion. The role of the back-diffusion parameter was emphasized as a factor responsible for the redistribution in columnar structure and equiaxed structure.
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Wang, Fa-Cheng, Hua-Yang Zhao, and Lin-Hai Han. "Analytical behavior of concrete-filled aluminum tubular stub columns under axial compression." In 12th international conference on ‘Advances in Steel-Concrete Composite Structures’ - ASCCS 2018. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/asccs2018.2018.7135.

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This paper presents numerical investigation of circular concrete-filled aluminum tubular (CFAT) stub columns under axial compression. The numerical models were developed using the finite element (FE) package ABAQUS. The parameters commonly employed in conventional CFST FE modeling have been discussed in this study. The nonlinearities of concrete and aluminum materials and the interaction between concrete and aluminum tube were considered. Numerical models were validated against collected experimental data. The ultimate loads, load-axial strain relationship and failure modes from numerical simulations were compared with those from experiments. The verified FE model was used to analyze structural behavior of full histories of the corresponding load-deformation N-ε response. Load-deformation N-ε curves for both concrete and aluminum tube were also presented. Upon on validation of the FE models, additional structural performance data over a wide range of diameter-to-thickness ratios, aluminum grades and concrete strengths were generated for parametric studies. The influences of diameter-to-thickness ratios, aluminum grades and concrete strengths on the ultimate strength were presented in this paper.
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Chen, S. C., C. F. Lu, R. Z. Chen, C. M. Wang, and P. C. Kuo. "Epitaxial Co80Pt20Films with Columnar Grains and Perpendicular Magnetic Anisotropy at Ambient Temperature." In 2016 International Conference of Asian Union of Magnetics Societies (ICAUMS). IEEE, 2016. http://dx.doi.org/10.1109/icaums.2016.8479767.

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Lo, Chi Yan, Malcolm Bolton, Yi Pik Cheng, Masami Nakagawa, and Stefan Luding. "Discrete Element Simulation of Granular Column Collapse." In POWDERS AND GRAINS 2009: PROCEEDINGS OF THE 6TH INTERNATIONAL CONFERENCE ON MICROMECHANICS OF GRANULAR MEDIA. AIP, 2009. http://dx.doi.org/10.1063/1.3180004.

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Alexiew, Dimiter, Daniel Brokemper, and Steve Lothspeich. "Geotextile Encased Columns (GEC): Load Capacity, Geotextile Selection and Pre-Design Graphs." In Geo-Frontiers Congress 2005. Reston, VA: American Society of Civil Engineers, 2005. http://dx.doi.org/10.1061/40777(156)12.

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Gong, Xibing, James Lydon, Kenneth Cooper, and Kevin Chou. "Microstructural Analysis and Nanoindentation Characterization of Ti-6Al-4V Parts From Electron Beam Additive Manufacturing." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36675.

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In this study, the microstructure analysis and nanoindentation characterization from electron beam additive manufacturing (EBAM) were experimentally investigated. Specimens with different build heights of an EBAM built part were tested for microstructure observations by optical microscopy and scanning electron microscopy. The correspondent Young’s modulus and hardness were measured by nanoindentation. Columnar prior β structure is found along the build direction from the X-plane, while the Z-plane is characterized by equiaxed grains and fine Widmanstätten (α+β) structure. The microstructure varies along the build height: the top layers present finer columnar prior β grains and inside Widmanstätten (α+β) structure, while the bottom layers show bigger percentage of α′ martensitic phase owing to the very high cooling rate. Nanoindentation tests identify the highest Young’s modulus of 127.9 GPa and hardness of 6.5 GPa from the top layers of Z-plane. The Young’s modulus and hardness of the middle layers are lower because of the repeated heating. The Z-plane shows higher mechanical properties compared to that of the X-plane. The enhancement of modulus and hardness of the Ti-6Al-4V alloy could be attributed to the strengthening phase of α′ and fine microstructure.
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Reports on the topic "Columnas de gravas"

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Walton, O. R., H. J. Vollmer, and V. S. Hepa. Wall-Friction Support of Vertical Loads in Submerged Sand and Gravel Columns. Office of Scientific and Technical Information (OSTI), August 2015. http://dx.doi.org/10.2172/1234608.

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