Temperature and time dependent threshold voltage characterization of AlGaN/GaN high electron mobility transistors

Relacionado con línea de investigación del GDS del ISOM ver http://www.isom.upm.es/dsemiconductores.php

Encyclopédie méthodique : Arts et métiers mécaniques ...

Mode of access: Internet.

Tratado completo de historia natural /

En port.: Se vende en Madrid y provincias en todas las librerías matriculadas en la espresada sociedad,: en Lima, Casa de los Señores Calleja, Ojea y Compañía.

The mechanical behaviour of cylindrical GRP panels

Glass reinforced plastic (GRP) is now an established material for the fabrication of sonar windows. Its good mechanical strength, light weight, resistance to corrosion and acoustic transparency, are all properties which fit it for this application. This thesis describes a study, undertaken at the Royal Naval Engineering College, Plymouth, into the mechanical behaviour of a circular cylindrical sonar panel. This particular type of panel would be used to cover a flank array sonar in a ship or submarine. The case considered is that of a panel with all of its edges mechanically clamped and subject to pressure loading on its convex surface. A comprehensive program of testing, to determine the orthotropic elastic properties of the laminated composite panel material is described, together with a series of pressure tests on 1:5 scale sonar panels. These pressure tests were carried out in a purpose designed test rig, using air pressure to provide simulated hydrostatic and hydrodynamic loading. Details of all instrumentation used in the experimental work are given in the thesis. The experimental results from the panel testing are compared with predictions of panel behaviour obtained from both the Galerkin solution of Flugge's cylindrical shell equations (orthotropic case), and finite element modelling of the panels using PAFEC. A variety of appropriate panel boundary conditions are considered in each case. A parametric study, intended to be of use as a preliminary design tool, and based on the above Galerkin solution, is also presented. This parametric study considers cases of boundary conditions, material properties, and panel geometry, outside of those investigated in the experimental work Final conclusions are drawn and recommendations made regarding possible improvements to the procedures for design, manufacture and fixing of sonar panels in the Royal Navy.

Attachment, psychological functioning, and resilience within the street involved youth populations: describing youth who access community agency support

Youth homelessness is defined within the literature as youth who have left their homes and are living independent of parental figures and/or caregivers, have no stable residence or source of income, and lack access to the supports needed to make the challenging transition into adulthood (Canadian Observatory on Homelessness, 2015). Previous research studying homeless (or street-involved) youth has primarily focused on risk factors hindering the development of this population, and has largely ignored resilience, coping, and help-seeking behaviours. The current study examined the attachment styles (both categorically and dimensionally), psychological functioning, resilience, and help-seeking behaviours in street-involved youth of St. John’s, Newfoundland. Face-to face interviews were completed over a four-month period with 63 youth (42 males, 21 females) aged 15-29 (Mage = 20.00), recruited from a local community organization providing outreach services to street-involved youth. Results revealed the disproportionate struggles of the street-involved youth population, and highlighted higher levels of attachment insecurity, psychological distress and lower resilience compared to normative peers. Findings also showed a significant difference in psychological functioning, overall resilience, and emotional reactivity based on individual attachment style. In an exploratory model of help-seeking, a positive relationship was found between overall resilience (defined as a sense of mastery and sense of relatedness) and frequency of community service access. However, contrary to predictions, no relationships were found between frequency of community service access and attachment, psychological functioning, or emotional reactivity. Implications of the present findings in development of interventions for street-involved youth are discussed, in addition to strengths and limitations of the present research, and suggested areas of future inquiry.

A análise de performance e o seu impacto no desempenho de uma equipa de futebol profissional

Atualmente, a preparação e desenvolvimento de uma equipa de futebol deve considerar não só aspetos relacionados com a metodologia do treino, como também da análise de performance, quer da própria equipa quer de equipas adversárias. O estágio desenvolveu-se integrado nas equipas técnicas que orientaram o plantel profissional do Estoril Praia SAD, durante a época 2014/2015. Na área 1, foi exposto o objetivo principal do trabalho apresentado neste relatório, que se prendeu com a necessidade de compreender de que forma é importante a análise da própria equipa e da equipa adversária, e ainda como essas análises são enquadradas e utilizadas no treino e na competição. Após a recolha de informação na literatura, relativa à análise de performance, e relacionada essa informação com a prática do dia-a-dia e ainda com as opiniões recolhidas através de entrevistas realizadas a dois elementos de uma das equipas técnicas, foi possível perceber a importância da análise na preparação e operacionalização das ideias de jogo da equipa técnica, não só durante os momentos competitivos, como em situações de treino. Na área 2 (Projeto de investigação/inovação) foi realizado um estudo que teve como finalidade perceber o impacto que tem a alteração de um treinador no decorrer da época desportiva, tentando relacionar essas decisões com diferentes contextos, percebendo se a alteração tem uma influência positiva ou negativa no rendimento das equipas contempladas no estudo. Posteriormente à sua realização, o estudo foi apresentado nas Jornadas Portuguesas de Psicologia do Desporto. Relativamente à área 3 (Relação com a comunidade), foi realizado um torneio que teve como principal foco, alertar os pais dos atletas para os valores positivos que podem ser promovidos e desenvolvidos através do desporto.

Changing family models in Spain: the impact of the sociodemographic factors

Abstract During the last few decades, there has been an increasing international recognition of the studies related to the analysis of the family models change, the focus being the determinants of the female employment and the problems related to the work family balance (Lewis, 2001; Petit & Hook, 2005Saraceno, Crompton & Lyonette, 20062008; Pfau-Effinger, 2012). The majority of these studies have been focused on the analysis of the work-family balance problems as well as the effectiveness of the family and gender policies in order to encourage female employment (Korpi et al., 2013). In Spain, special attention has been given to the family policies implemented, the employability of women and on the role of the father in the family (Flaquer et al., 2015; Meil, 2015); however, there has been far less emphasis on the analysis of the family cultural models (González and Jurado, 2012; Crespi and Moreno, 2016). The purpose of this paper is to present some of the first results on the influence of the socio-demographic factors on the expectations and attitudes about the family models. This study offers an analytical reflection upon the foundation of the determinants of the family ambivalence in Spain from the cultural and the institutional dimension. This study shows the Spanish family models of preferences following the Pfau-Effinger (2004) classification of the famiy living arrangements. The reason for this study is twofold; on the one hand, there is confirmed the scarcity of studies that have focused their attention on this objective in Spain; on the other hand, the studies carried out in the international context have confirmed the analytical effectiveness of researching on the attitude and value changes to explain the meaning and trends of the family changes. There is also presented some preliminary results that have been obtained from the multinomial analysis related to the influence of the socio-demographic factors on the family model chosen by the individuals in Spain (father and mother working full time; mother part-time father full-time; mother not at work father full-time; mother and father part-time). 3 The database used has been the International Social Survey Programme: Family and Changing Gender Roles IV- ISSP 2012-. Spain is the only country of South Europe that has participated in the survey. For this reason it has been considered as a representative case study.

Sistema di navigazione aumentata per Smart Glasses

Questa tesi si pone come obiettivo di arricchire l’applicazione per dispositivi Android creata da OpenTripPlanner, aggiungendo funzionalità di navigazione aumentata, rendendola utilizzabile da Smart Glasses. L’utente sarà guidato a passo a passo nel percorso grazie a informazioni visive e uditive sulle direzioni da prendere. L’applicazione può essere personalizzata per l’utente che la sta utilizzando grazie alla possibilità di inserire le proprie generalità e informazioni, utili per calcolare le calorie bruciate dall’utente durante il tragitto. All’applicazione l’utente può anche connettere, tramite Bluetooth, un mi band. In questo modo, una volta raggiunta la destinazione prescelta l’utente può avere informazioni sul numero di passi effettuati durante il tragitto e le calorie bruciate.

Determinação do período crítico para prevenção da interferência de plantas daninhas na cultura de soja (Glycine max): uso do modelo "Broken-stick".

Visando fornecer subsídios para programas de manejo de plantas daninhas em culturas agrícolas, foi realizado o presente estudo. Assim, foi conduzido um experimento de campo em Botucatu (Sao Paulo), com o objetivo de determinar, através do procedimento estatístico de análise de regressão, o período crítico para prevenção da interferência (PCPI) de plantas daninhas de folha larga na produtividade da cultura de soja. Foi utilizado o delineamento experimental em blocos casualizados. A cultura foi mantida na presença das plantas daninhas de folha larga por diferentes períodos. O período crítico determinado foi de 21 a 30 dias após a emergência da cultura, segundo ajuste dos dados de produtividade ao modelo "Broken-stick". No entanto, o período crítico determinado apresentou-se de modo que permite o controle através do uso, uma única vez, de método momentâneo, sem efeito residual.