Search results for "shape"
showing 10 items of 585 documents
Sizing and shape optimization material use in 10 bar trusses
2021
Truss optimization has the goal of achieving savings in costs and material while maintaining structural characteristics. In this research a 10 bar truss was structurally optimized in Rhino 6 using genetic algorithm optimization method. Results from previous research where sizing optimization was limited to using only three different cross-sections were compared to a sizing and shape optimization model which uses only those three cross-sections. Significant savings in mass have been found when using this approach. An analysis was conducted of the necessary bill of materials for these solutions. This research indicates practical effects which optimization can achieve in truss design.
I Barrai, picapedrers cagliaritani della seconda metà del Cinquecento. Stato degli studi e nuove ipotesi
2014
This essay is focused on the Barrai family, a group of stonecutters operating in Cagliari between 15th and 16th centuries. The family played a leading role in the construction and diffusion of star-shaped rib vaults in the late Sardinian 16th centuries religious architecture. The study attempts to systematize available evidence and information about the Barrai family in order to provide a starting point for further investigation. New hypotheses about the family’s genealogy and activity during the second half of the 16th century are also explored.
Finding Prediction Limits for a Future Number of Failures in the Prescribed Time Interval under Parametric Uncertainty
2012
Computing prediction intervals is an important part of the forecasting process intended to indicate the likely uncertainty in point forecasts. Prediction intervals for future order statistics are widely used for reliability problems and other related problems. In this paper, we present an accurate procedure, called ‘within-sample prediction of order statistics', to obtain prediction limits for the number of failures that will be observed in a future inspection of a sample of units, based only on the results of the first in-service inspection of the same sample. The failure-time of such units is modeled with a two-parameter Weibull distribution indexed by scale and shape parameters β and δ, …
Trial Methods for Nonlinear Bernoulli Problem
1997
In this article we consider a free boundary problem which is related to formation of waves on a fluid surface (for example the ship waves). We study the possibility to construct ‘trial’ methods where one solves a sequence of standard flow problems formulated in different geometries that converge to the final free boundary. Furthermore, we use the shape optimization techniques to analyse the convergence of the fixed point iteration near a fixed point. For stream function case we conclude that the fast convergence can be obtained by using non-standard boundary conditions and we present numerical results to confirm the analysis.
Phytoplankton distribution along trophic gradients within and among reservoirs in Catalonia (Spain)
2008
SUMMARY 1. Longitudinal gradients in the epilimnetic waters of stratified reservoirs provide a useful database to study changing environmental conditions. The spatial distribution, assemblage structure and specific adaptations of phytoplankton assemblages can be analysed along these gradients over short time scales. 2. Four reservoirs with a similar typology, located along an altitudinal gradient in the same eco-region, were sampled along their longitudinal axes. In total, 19 sampling stations provided a trophic spectrum, ranging from oligo-mesotrophy to hypertrophy, which was quantified by calculating the trophic state index of each sampling station in the four reservoirs. 3. Several patte…
Black hole lightning due to particle acceleration at subhorizon scales
2015
Supermassive black holes with masses of millions to billions of solar masses are commonly found in the centers of galaxies. Astronomers seek to image jet formation using radio interferometry, but still suffer from insufficient angular resolution. An alternative method to resolve small structures is to measure the time variability of their emission. Here, we report on gamma-ray observations of the radio galaxy IC 310 obtained with the MAGIC telescopes revealing variability with doubling time scales faster than 4.8 min. Causality constrains the size of the emission region to be smaller than 20\% of the gravitational radius of its central black hole. We suggest that the emission is associated …
Platelet, Not Endothelial, P-Selectin Expression Contributes to Generation of Immunity in Cutaneous Contact Hypersensitivity
2010
Leukocyte extravasation is a prerequisite for host defense and autoimmunity alike. Detailed understanding of the tightly controlled and overlapping sequences of leukocyte extravasation might aid development of novel therapeutic strategies. Leukocyte extravasation is initiated by interaction of selectins with appropriate carbohydrate ligands. Lack of P-selectin expression leads to decreased contact hypersensitivity responses. Yet, it remains unclear if this is due to inhibition of leukocyte extravasation to the skin or due to interference with initial immune activation in lymph nodes. In line with previous data, we here report a decreased contact hypersensitivity response, induced by 2,4,-di…
Registration-based Construction of a Whole-body Human Phantom Library for Anthropometric Modeling.
2020
Various computational human phantoms have been proposed in the past decades, but few of them include delicate anthropometric variations. In this study, we build a whole-body phantom library including 145 anthropometric parameters. This library is constructed by registration-based pipeline, which transfers a standard whole-body anatomy template to an anthropometry-adjustable body shape library (MakeHuman™). Therefore, internal anatomical structures are created for body shapes of different anthropometric parameters. Based on the constructed library, we can generate individualized whole-body phantoms according to given arbitrary anthropometric parameters. Moreover, the proposed phantom library…
ANÁLISIS SOBRE LAS FORMAS CORPORALES Y LOS PATRONES DE ACTIVIDAD FÍSICA DOMINANTES EN UNA COLECCIÓN DE LIBROS PARA COLOREAR
2014
Los materiales curriculares juegan un papel importante en la construcción del concepto del cuerpo debido a que son transmisores de conocimientos, ideas y valores. El objetivo del estudio consiste en analizar si las imágenes de una colección de libros para colorear y dibujar titulada Doodles para niños y Doodles para niñas señalan estereotipos sexistas sobre los modelos corporales y patrones de actividad física dominantes. Un grupo observacional independiente estudió las imágenes del cuerpo en los dos libros a través de un análisis de contenido con un sistema de categorías (género, edad, somatotipo, espacio y tipo de actividad física) previamente validado por expertos. Por lo tanto, se encon…
Human Haemato-Endothelial Precursors: Cord Blood CD34+ Cells Produce Haemogenic Endothelium
2012
Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-), triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45-) capable of functioning as haemogenic endothelium. These cells, proven to give…