Modelling the crush behaviour of thermoplastic composites

Thermoplastic composites are likely to emerge as the preferred solution for meeting the high-volume production demands of passenger road vehicles. Substantial effort is currently being directed towards the development of new modelling techniques to reduce the extent of costly and time consuming physical testing. Developing a high-fidelity numerical model to predict the crush behaviour of composite laminates is dependent on the accurate measurement of material properties as well as a thorough understanding of damage mechanisms associated with crush events. This paper details the manufacture, testing and modelling of self-supporting corrugated-shaped thermoplastic composite specimens for crashworthiness assessment. These specimens demonstrated a 57.3% higher specific energy absorption compared to identical specimen made from thermoset composites. The corresponding damage mechanisms were investigated in-situ using digital microscopy and post analysed using Scanning Electron Microscopy (SEM). Splaying and fragmentation modes were the 2 primary failure modes involving fibre breakage, matrix cracking and delamination. A mesoscale composite damage model, with new non-linear shear constitutive laws, which combines a range of novel techniques to accurately capture the material response under crushing, is presented. The force-displacement curves, damage parameter maps and dissipated energy, obtained from the numerical analysis, are shown to be in a good qualitative and quantitative agreement with experimental results. The proposed approach could significantly reduce the extent of physical testing required in the development of crashworthy structures.  

Does video feedback analysis improve CPR performance in phase 5 medical students?

Background The use of simulation in medical education is increasing, with students taught and assessed using simulated patients and manikins. Medical students at Queen’s University of Belfast are taught advanced life support cardiopulmonary resuscitation as part of the undergraduate curriculum. Teaching and feedback in these skills have been developed in Queen’s University with high-fidelity manikins. This study aimed to evaluate the effectiveness of video compared to verbal feedback in assessment of student cardiopulmonary resuscitation performance Methods Final year students participated in this study using a high-fidelity manikin, in the Clinical Skills Centre, Queen’s University Belfast. Cohort A received verbal feedback only on their performance and cohort B received video feedback only. Video analysis using ‘StudioCode’ software was distributed to students. Each group returned for a second scenario and evaluation 4 weeks later. An assessment tool was created for performance assessment, which included individual skill and global score evaluation. Results One hundred thirty eight final year medical students completed the study. 62 % were female and the mean age was 23.9 years. Students having video feedback had significantly greater improvement in overall scores compared to those receiving verbal feedback (p = 0.006, 95 % CI: 2.8–15.8). Individual skills, including ventilation quality and global score were significantly better with video feedback (p = 0.002 and p < 0.001, respectively) when compared with cohort A. There was a positive change in overall score for cohort B from session one to session two (p < 0.001, 95 % CI: 6.3–15.8) indicating video feedback significantly benefited skill retention. In addition, using video feedback showed a significant improvement in the global score (p < 0.001, 95 % CI: 3.3–7.2) and drug administration timing (p = 0.004, 95 % CI: 0.7–3.8) of cohort B participants, from session one to session two. Conclusions There is increased use of simulation in medicine but a paucity of published data comparing feedback methods in cardiopulmonary resuscitation training. Our study shows the use of video feedback when teaching cardiopulmonary resuscitation is more effective than verbal feedback, and enhances skill retention. This is one of the first studies to demonstrate the benefit of video feedback in cardiopulmonary resuscitation teaching.

Atividades educativas na prevenção da aids na rede básica municipal de saúde: participação do enfermeiro

TORRES, Gilson de Vasconcelos; ENDERS, Bertha Cruz. Atividades educativas na prevencao da AIDS em uma rede basica municipal de saude: participacao do enfermeiro. Rev.latino-am.enfermagem, Ribeirao Preto, v.7, n.2, p.71-77, abril 1999. Disponivel em: . Acesso em: 04 set. 2010.

Estudo Preliminar de Adaptação e Validação da Escala de Avaliação do Eu Resiliente: resiliência, autodano e ideação suicida em adolescentes

Introdução: Em Portugal, são escassos os instrumentos validados para a população adolescente, que avaliem o importante construto da resiliência. Assim, o principal objetivo deste estudo consistiu na adaptação e validação preliminar da Escala de Avaliação do EU Resiliente (EAER) para adolescentes portugueses. Como segundo objetivo pretendemos, ainda, explorar as associações, na mesma amostra, entre a resiliência, o autodano e a ideação suicida na adolescência. Método: A amostra foi constituída por 226 adolescentes (sexo masculino, n = 139, 61,5%), entre os 12 e os 18 anos, que preencheram um protocolo composto por um questionário sociodemográfico, pela Escala de Avaliação do EU Resiliente (EAER), pelo Questionário de Impulso, Autodano e Ideação Suicida na Adolescência (QIAIS-A) e pela Escala de autoconceito. Resultados: Os resultados obtidos mostraram que a EAER possui boa fidelidade/consistência interna (α = 0,857) e boa estabilidade temporal (r = 0,720). Uma análise de componentes principais mostrou que a EAER apresenta três fatores: fator suporte externo, fator forças pessoais internas e fator estratégias de coping. Encontraram-se correlações negativas entre a resiliência e o autodano e ideação suicida e correlações positivas entre a resiliência e o autoconceito, confirmando-se a validade divergente e convergente da EAER. Verificaram-se níveis elevados de resiliência nos adolescentes da nossa amostra (M = 58,69; DP = 6,67). Na amostra total, 61,5% (n = 139) apresentou ideação suicida e 26,5% (n = 60) apresentou comportamentos de autodano. Conclusão: No seu conjunto, a EAER possui boas características psicométricas, pelo que pode ser considerada uma escala válida e útil e que pode ser usada com segurança na avaliação da resiliência em adolescentes portugueses. Com este estudo alargámos o leque de instrumentos válidos para a medição da resiliência em adolescentes e contribuímos para o avanço da investigação na área da adolescência em Portugal. / Introduction: In Portugal, there are few validated instruments to the adolescent population, to assess the important construct of resilience. Thus, the main objective of this study was the preliminary adaptation and validation of the Escala de Avaliação do EU Resiliente (EAER) to Portuguese adolescents. As a second objective, there is an intention to also explore the associations, on the same sample, between resilience, self-harm and suicidal ideation in adolescence. Method: The sample consisted of 226 adolescents (male, n = 139, 61.5%), between 12 and 18 years, who filled in a protocol consisting of a sociodemographic questionnaire, by the Escala de Avaliação do EU Resiliente (EAER), by the Impulse, Self-harm and Suicide Ideation Questionnaire for Adolescents (ISSIQ-A) and by the Self-concept Scale. Results: The results showed that the EAER has good fidelity/internal consistency (α = 0.857) and good temporal stability (r = 0.720). A principal component analysis showed that EAER has three factors: external support factor, internal personal strengths factor and coping strategies factor. There were negative correlations between resilience and the self-harm and suicidal ideation and positive correlations between resilience and self-concept, confirming the divergent and convergent validity of EAER. There were high levels of resilience in the adolescents of the sample (M = 58.69, SD = 6.67). In the total sample, 61.5% (n = 139) had suicidal ideation and 26,5% (n = 60) had self-harm behaviors. Conclusion: As a whole, the EAER has good psychometric properties, therefore it can be considered a valid and useful range, and can be safely used in the evaluation of resilience in Portuguese adolescents. With this study we have extended the range of valid instruments for the measurement of resilience in adolescents and contributed to the advance of research in the adolescence area in Portugal.

VISSIM Calibration for Urban Freeways, 2015

In urban areas, interchange spacing and the adequacy of design for weaving, merge, and diverge areas can significantly influence available capacity. Traffic microsimulation tools allow detailed analyses of these critical areas in complex locations that often yield results that differ from the generalized approach of the Highway Capacity Manual. In order to obtain valid results, various inputs should be calibrated to local conditions. This project investigated basic calibration factors for the simulation of traffic conditions within an urban freeway merge/diverge environment. By collecting and analyzing urban freeway traffic data from multiple sources, specific Iowa-based calibration factors for use in VISSIM were developed. In particular, a repeatable methodology for collecting standstill distance and headway/time gap data on urban freeways was applied to locations throughout the state of Iowa. This collection process relies on the manual processing of video for standstill distances and individual vehicle data from radar detectors to measure the headways/time gaps. By comparing the data collected from different locations, it was found that standstill distances vary by location and lead-follow vehicle types. Headways and time gaps were found to be consistent within the same driver population and across different driver populations when the conditions were similar. Both standstill distance and headway/time gap were found to follow fairly dispersed and skewed distributions. Therefore, it is recommended that microsimulation models be modified to include the option for standstill distance and headway/time gap to follow distributions as well as be set separately for different vehicle classes. In addition, for the driving behavior parameters that cannot be easily collected, a sensitivity analysis was conducted to examine the impact of these parameters on the capacity of the facility. The sensitivity analysis results can be used as a reference to manually adjust parameters to match the simulation results to the observed traffic conditions. A well-calibrated microsimulation model can enable a higher level of fidelity in modeling traffic behavior and serve to improve decision making in balancing need with investment.

Virtual Worlds for Learning

This chapter examines four papers that have been influential in the use of virtual worlds for learning, but also draws on a range of other research and literature in order to locate virtual world learning across the landscape of higher education. Whilst there is sometimes a misconception that research into learning in virtual worlds is very new, the field began to develop in the late 1990’s and has continued since then. Typical examples of the first iterations of virtual worlds include Second Life, Active Worlds, and Kaneva, which have been available for up to 20 years. The second generation is currently being developed, examples being High Fidelity and Project Sansar. The chapter reviews the literature in this field and suggests central themes that emerge are: Socialisation; Presence and immersion in virtual world learning; Learning collaboratively and Trajectories of participation

Exploring Habitability Markers, Biosignatures, and Their False Positives Using Spectral Models of Terrestrial Exoplanets

Thesis (Ph.D.)--University of Washington, 2016-08

Development and regeneration of neuronal circuits in the vertebrate retina

Thesis (Ph.D.)--University of Washington, 2016-08

Convex Optimization Algorithms and Statistical Bounds for Learning Structured Models

Thesis (Ph.D.)--University of Washington, 2016-08

The Usability of a Commercial Game Physics Engine to Develop Physics Educational Materials: an Investigation

Commercial computer games contain “physics engine” components, responsible for providing realistic interactions among game objects. The question naturally arises of whether these engines can be used to develop educational materials for high school and university physics education. To answer this question, the author's group recently conducted a detailed scientific investigation of the physics engine of Unreal Tournament 2004 (UT2004). This article presents their motivation, methodology, and results. The author presents the findings of experiments that probed the accessibility and fidelity of UT2004's physics engine, examples of educational materials developed, and an evaluation of their use in high school classes. The associated pedagogical implications of this approach are discussed, and the author suggests guidelines for educators on how to deploy the approach. Key resources are presented on an associated Web site.

Learning Physics with the Unreal Tournament Engine

Computer games such as Unreal Tournament (UT2004 and UT3) contain a 'physics engine' responsible for producing believable dynamic interactions between players and objects in the three-dimensional (3D) virtual world of a game. Through a series of probing experiments we have evaluated the fidelity and internal consistency of the UT2004 physics engine. These experiments have then led to the production of resources which may be used by learners and teachers of secondary-school physics. We also suggest an approach to learning, where both teachers and pupils may produce learning materials using the Unreal Tournament editor 'UnrealEd'.

Sobre (vivência) e mortalidade de pequenos negócios: o caso de mercados varejistas potiguares

This paper‟s starting point was the objective of understanding the relation between the reasons pointed out by small businesses owners for the continuity or shutdown of their businesses, and the reasons presented by the Environmental Theories. The paper discusses the Environmental Theories understand that it is supported by a systemic metaphor speech, discussing the theme in terms of organizational survival and mortality . The text reviews the literature showing the changes in the administrative thinking regarding the organization versus environment relation, and presenting general ideas about the micro and small businesses. In methodological terms, the qualitative approach was used in the research. Regarding the data collection technique, an in-depth thematic interview was used. It was carried out considering the elements of the techniques of life history and oral history, always giving priority to real world related narratives told by the interviewed subjects. The empirical corpus of the research was made up of seven owners of small retail businesses in two Potiguar cities: Natal and Mossoró. The interpretative and analytical process focused, at first, on the reflexive dialogue with each one of the owners‟ professional life history and business management experience, constituting the first level of analysis: reflections on individual narratives; and, afterwards, the interpretative process was developed through the analysis of all the subjects‟ statements, identifying the recurring themes and constituting the second level of analysis: reflection on the totalizing narrative. The themes identified in the totalizing narrative, that refer to the continuity of the businesses are: evolution, control, fidelity, liking what one does for a living. The themes that came up as reasons for shutdown are: lack of empathy with the business, lack of evolution, competition problems, suppliers and the government. The text synthesizes its comprehensions affirming that the reasons associated with continuity and shutdown of small markets, for this group of owners specifically, come up as a permanent tension between the volunteerism (quite human) and the determinism (systemic). The tension is shown in testimonies that at the same time evoke the organicist systemic logic through the themes evolution/no evolution, and also counterpoints with themes related to the interested human action, based on desires, feelings and personal convictions such as: liking what one does/ lack of empathy. As for the reflexive dialogue between the postulates of the Environmental Theories and the narratives, the results make it possible to affirm that, differently from the tension expressed by the subjects while talking about their reasons, the reasons associated with survival and mortality of businesses according to the Environmental Theories are theoretically polarized, seeming to preach options that are stagnated and shaping towards the subjects involved in the organization-environment relation

Évaluation de la modélisation de la taille de grain de neige du modèle multi-couches thermodynamique SNOWPACK: implication dans l'évaluation des risques d'avalanches

Résumé: L’Institut pour l'étude de la neige et des avalanches en Suisse (SLF) a développé SNOWPACK, un modèle thermodynamique multi-couches de neige permettant de simuler les propriétés géophysiques du manteau neigeux (densité, température, taille de grain, teneur en eau, etc.) à partir desquelles un indice de stabilité est calculé. Il a été démontré qu’un ajustement de la microstructure serait nécessaire pour une implantation au Canada. L'objectif principal de la présente étude est de permettre au modèle SNOWPACK de modéliser de manière plus réaliste la taille de grain de neige et ainsi obtenir une prédiction plus précise de la stabilité du manteau neigeux à l’aide de l’indice basé sur la taille de grain, le Structural Stability Index (SSI). Pour ce faire, l’erreur modélisée (biais) par le modèle a été analysée à l’aide de données précises sur le terrain de la taille de grain à l’aide de l’instrument IRIS (InfraRed Integrated Sphere). Les données ont été recueillies durant l’hiver 2014 à deux sites différents au Canada : parc National des Glaciers, en Colombie-Britannique ainsi qu’au parc National de Jasper. Le site de Fidelity était généralement soumis à un métamorphisme à l'équilibre tandis que celui de Jasper à un métamorphisme cinétique plus prononcé. Sur chacun des sites, la stratigraphie des profils de densités ainsi des profils de taille de grain (IRIS) ont été complétés. Les profils de Fidelity ont été complétés avec des mesures de micropénétromètre (SMP). L’analyse des profils de densité a démontré une bonne concordance avec les densités modélisées (R[indice supérieur 2]=0.76) et donc la résistance simulée pour le SSI a été jugée adéquate. Les couches d’instabilités prédites par SNOWPACK ont été identifiées à l’aide de la variation de la résistance dans les mesures de SMP. L’analyse de la taille de grain optique a révélé une surestimation systématique du modèle ce qui est en accord avec la littérature. L’erreur de taille de grain optique dans un environnement à l’équilibre était assez constante tandis que l’erreur en milieux cinétique était plus variable. Finalement, une approche orientée sur le type de climat représenterait le meilleur moyen pour effectuer une correction de la taille de grain pour une évaluation de la stabilité au Canada.

The Role of Feminine and Masculine Norms in College Women's Alcohol Use

Current literature suggests not only that men and women can conform to both feminine and masculine norms, but that women who adhere to certain masculine norms may be at greater risk for problematic alcohol use. This study examined conformity to both masculine and feminine norms, and how conformity to distinct norms influenced heavy episodic drinking and alcohol-related problems among a sample of underage college women (N= 645). Results demonstrated that the masculine norms risk-taking and emotional control were associated with increased HED, while the masculine norm power over women was associated with a decrease in HED. Traditional feminine norms, including modesty and sexual fidelity, were associated with a decrease in HED and alcohol-related problems. The feminine norm relational was associated with increased HED, while the norms thinness and appearance were associated with increased alcohol-related problems. The study’s theoretical and clinical implications are discussed.

Ketterän ohjelmistokehittämisen hyödyntäminen käyttöliittymäkehityksessä asiakkaiden todellisen tarpeen ymmärtämiseksi

Työn tavoitteena oli toimintatutkimuksen kautta tutkia ketterän ohjelmistokehityksen keinoin toteutetun käyttöliittymäkehityksen kykyä vastata asiakkaiden todellisiin tarpeisiin. Työssä haettiin tapaustutkimusyritykselle olemassa olevan työkalun uuden version käyttöliittymän toteutusvaihtoehtoja ja toteutettiin korkean tarkkuuden prototyyppejä näitä hyödyntäen. Ketterän ohjelmistokehityksen arvot ja periaatteet soveltuivat kehitysprosessissa käytettäviksi erinomaisesti. Iteratiivinen lähestymistapa kehitykseen ja läheinen yhteistyö tapaustutkimusyrityksen ja kandidaatintyöntekijän kanssa mahdollistivat yrityksen odotusten täyttämisen. Työkalun käyttöliittymä saatettiin tasolle, joka mahdollistaa jatkokehittämisen aloituksen. Kattavamman testauttamisen sisällyttäminen kehitysprosessiin olisi edesauttanut vielä paremman lopputuloksen saavuttamista.