66 research outputs found
A survey on structured deformations
In this work we briefly describe the theory of (first-order) structured deformations of continua as well as the variational problems arising from this theory.
Structured Deformations of Continua: Theory and Applications
The scope of this contribution is to present an overview of the theory of
structured deformations of continua, together with some applications.
Structured deformations aim at being a unified theory in which elastic and
plastic behaviours, as well as fractures and defects can be described in a
single setting. Since its introduction in the scientific community of rational
mechanicists (Del Piero-Owen, ARMA 1993), the theory has been put in the
framework of variational calculus (Choksi-Fonseca, ARMA 1997), thus allowing
for solution of problems via energy minimization. Some background, three
problems and a discussion on future directions are presented.Comment: 11 pages, 1 figure, 1 diagram. Submitted to the Proceedings volume of
the conference CoMFoS1
The Neumann problem in thin domains with very highly oscillatory boundaries
In this paper we analyze the behavior of solutions of the Neumann problem
posed in a thin domain of the type with and , defined by smooth
functions and , where the function is supposed to be
-periodic in the second variable . The condition implies
that the upper boundary of this thin domain presents a very high oscillatory
behavior. Indeed, we have that the order of its oscillations is larger than the
order of the amplitude and height of given by the small parameter
. We also consider more general and complicated geometries for thin
domains which are not given as the graph of certain smooth functions, but
rather more comb-like domains.Comment: 20 pages, 4 figure
On the commutability of homogenization and linearization in finite elasticity
We study non-convex elastic energy functionals associated to (spatially)
periodic, frame indifferent energy densities with a single non-degenerate
energy well at SO(n). Under the assumption that the energy density admits a
quadratic Taylor expansion at identity, we prove that the Gamma-limits
associated to homogenization and linearization commute. Moreover, we show that
the homogenized energy density, which is determined by a multi-cell
homogenization formula, has a quadratic Taylor expansion with a quadratic term
that is given by the homogenization of the quadratic term associated to the
linearization of the initial energy density
Parental needs and stress in Neonatal Intensive Care Units: effect of data collection period
The assessment of parental needs and stress is essential for the implementation of quality family-centred care in Neonatal Intensive Care Units (NICUs). Therefore, we aim to assess the effect of data collection period on self-reported needs and stress among parents of very preterm infants hospitalized in level III NICU, comparing those interviewed 8-14 days after child s admission with those interviewed 15-22 days after that event. Between January and September 2013, parents filled the NICU Family Needs Inventory and the Parental Stress Scale in NICU. Needs of assurance and proximity were the most valued, independently of the time of interview. A tendency for attributing a higher relevance to support needs and to stress levels regarding change in parental role was observed throughout the hospitalization
Analysis and diagnosis of a hand tools production system
All rights reserved. Engineers must have a set of professional competences, which includes sound technical knowledge and the ability to solve engineering problems, integrated with a set of transversal competences, which must mobilized for managing projects, working in teams and communicate with the others effectively. The development of these sets of competences can be supported by projects in interaction with companies. This article reports the work developed by a group of students on the Integrated Project of the 4 th year of Industrial Engineering and Management of the University of Minho. The main objective of this work is to describe the type of project that a group of students can develop in interaction with an industrial company, and reflect about the main results that this project have for the development of their competences and for the company. This is a descriptive paper based upon on reports and the experience of the students. The target of the project was the diagnosis and analysis of a production system in an industrial environment. The company chosen to develop this project is a multinational and pioneer company on the manufacturing of hand tools. The content of this article will mainly cover the internal supplier of materials (Mizusumashi), namely the standardization of the Mizusumashi route and the improvement of the components` warehouse (materials organization and visual management). The suggested modifications can result in a 30% decrease of the time wasted in the warehouse, a 20% decrease of the time it takes the Mizusumashi to complete a full route, reaching the 45 minutes the company requested. The students were able to fulfil the project milestones and integrate the company culture in their weekly visits, during the 15 weeks of the project. Furthermore, the company showed to be very satisfied with their behaviour and performance.(undefined)info:eu-repo/semantics/publishedVersio
Humic acids induce the expression of nitrate transporters in passion-fruit seedlings.
The management of organic fertilization in passion fruit has been carried out empirically based on the responses of the crops and the experience of farmers. Knowledge of the physiological responses of plants to organic fertilizers is essential to optimize fertilization programs. The objective of this study was to evaluate the differential expression of genes coding for nitrate transporters as well as plasma membrane H+-ATPase in passion fruit seedlings treated with different organic fertilizers in the presence or not of humic acids. The equivalent of one gram of total nitrogen dissolved in water from cattle manure, castor oil cake and urea were added and the seedlings were treated or not with a suspension of humic acids (2 mmol/L). Differential expression of low and high affinity nitrate transporters (PeNRT2.2 and PeNRT1.1 PeNRT2.2e) and H+-ATPase (PeMha) was performed by qRT-PCR. The use of cattle manure increased the differential expression of the high affinity transporter regarding to the control. The application of humic acids amplified the increase observed in the differential transcription of the high-affinity transporter with manure and urea fertilization, with no effect observed with the use of castor oil cake. Humic acids induced transcription of the gene encoding H+-ATPases in all treatments compared to control. The application of biofertilizer based on humic acids in low concentrations directly on the plant can be used with the objective of optimizing the organic fertilization of passion fruit with cattle manure and urea.TĂtulo em PortuguĂȘs: Ăcidos hĂșmicos induzem a expressĂŁo dos transportadores de nitrato em mudas de maracujazeir
Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic
This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic
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