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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Compétences non techniques en neurochirurgie / Non-technical Skills in Neurosurgery

Hénaux, Pierre-Louis 01 April 2019 (has links)
Le domaine de la chirurgie de par son environnement sensible, ses enjeux de qualité et de sécurité se rapproche naturellement d’autres univers tels que l’industrie nucléaire, l’aviation civile et le domaine militaire. La technicité voire même la connaissance déclarative de chaque individu composant un élément de l’ensemble d’individus interagissant ensemble dans ces environnements ne suffisent pas à atteindre des niveaux suffisants de sécurité. Plus de 70% des évènements indésirables graves seraient liés à des problèmes humains de coordination et de communication. Les compétences non techniques (CNT) sont ainsi nécessaires pour assurer une performance efficiente et sûre. La première partie de ce travail fait un état des lieux de la littérature sur les CNT en chirurgie. Après des définitions générales et un positionnement de ces compétences vis-à-vis notamment des compétences techniques et procédurales, nous présentons une revue systématique de la littérature des CNT dans le domaine spécifique de la neurochirurgie. La deuxième partie de ce travail s’intéresse quant à elle aux compétences interpersonnelles en focalisant le propos sur le travail en équipe et la communication. Le concept de familiarité au sein d’une équipe est exploré. Pour ce faire, nous présentons une étude observationnelle qui a été réalisée en environnement réel de bloc opératoire de neurochirurgie portant sur les interruptions de tâches et le travail d’équipe. Ces interruptions de tâches sont en effet des évènements itératifs entrainant la mobilisation de CNT au sein d’un groupe de professionnels. La troisième partie est consacrée aux compétences cognitives avec une étude reposant sur des entretiens de neurochirurgiens de différents niveaux d’expertise ; celle-ci ayant pour objectif de mieux comprendre la représentation mentale que se fait le chirurgien lors de son planning opératoire pré-chirurgical. La méthodologie qualitative de la théorisation enracinée est utilisée dans cette partie et nous justifions son emploi pour ce travail. / The field of surgery with its sensitive environment, its quality and safety issues is naturally close to other work environments such as the nuclear industry, civil aviation and the armed forces. The technical expertise and even the declarative knowledge of each individual component of the set of individuals interacting together in these environments are not sufficient to achieve sufficient safety levels. More than 70% of serious adverse events are due to human coordination and communication issues. Non-technical skills (NTS) are thus essential to ensure efficient and safe performance. The first part of this work is a review of the literature on NTS in surgery. After giving general definitions and positioning these skills with respect to technical and procedural skills, we present a systematic review of the CNT literature in thespecific field of neurosurgery. The second part of this work focuses on interpersonal skills: on teamwork and communication. The concept of crew familiarity is explored. In order to achieve this, we present an observational study carried out in a real neurosurgical operating room environment dealing with workflow disruptions and involving teamwork. These workflow disruptions are iterative events leading to the mobilization of NTS within a group of professionals. The third part is dedicated to cognitive skills with a study based on interviews of neurosurgeons with different levels of expertise. The aim is to better understand the surgeon’s mental representation during preoperative surgical planning. Grounded theory approach, a qualitative methodology, is used in this part and we justify its use for this work.
22

Ohm … Pardon the Interruption! An Exploration of Mindfulness as a Buffer against the Effects of Intrusions

Fletcher, Keaton Allen 29 June 2016 (has links)
Previous research has provided a helpful, albeit narrow, understanding of task interruptions as related to outcomes such as wellness and performance (e.g., Eyrolle & Cellier, 2000). Building on this foundation by viewing interruptions through the broader theoretical context of the theory of mental workload, this study sought to explain the cognitive processes underlying the negative performance effects often associated with interruptions and to apply an intervention aimed at mitigating these effects. Specifically, mindfulness has emerged as a promising method for reducing the cognitive burden of interruptions. This study examined the effects of intrusions (a type of interruption) on psychological strain and performance through perceived mental workload. Although perceived mental workload did predict strain outcomes, the overall mediation models failed to reach significance. Results also failed to support the hypothesized effect of state mindfulness as a potential moderator. A set of post hoc analyses, however, found that intrusion perceptions acted as a mediator between intrusion condition and psychological strain outcomes. Further, this mediation was moderated by state mindfulness, which in turn was moderated by the intrusion time. Specifically, the indirect effect of intrusion condition on strain outcomes was such that individuals experienced more strain if they received an intrusion compared to those who were not given an intrusion, unless they completed the form quickly and were also low on state mindfulness, in which case there was no difference in strain outcomes based on whether they experienced an intrusion. Together, these results suggest that intrusion perceptions play key roles in strain outcomes, and that moderators of these relationships should be further explored.
23

O modelo SLIM (\"Self-Consistently Interception Model\") para estimativa da incidência de descargas atmosféricas em estruturas - avaliação e aplicação na análise do desempenho de linhas de transmissão de energia / The Self-consistently Interception Model (SLIM) for estimating the lightning incidence to structures evaluation of the model and application to the analysis of lightning performance of power transmission lines

Acácio Silva Neto 19 April 2012 (has links)
O desempenho de uma linha de transmissão de energia está diretamente ligado ao número médio anual de descargas que nela incidem, o qual depende da densidade média de descargas ao solo na região e também do grau de exposição da linha. Modelos com diferentes graus de complexidade são encontrados na literatura para a estimativa da área de atração de estruturas a descargas atmosféricas. Entretanto, além das grandes simplificações sobre a física das descargas nas quais a maioria desses modelos se baseia, até recentemente não era possível considerar a configuração tridimensional das estruturas. Essa é uma limitação importante, pois detalhes do objeto afetam o campo elétrico e, consequentemente, o processo de formação do líder ascendente. Nesse contexto, o modelo desenvolvido em 2006 por Becerra e Cooray - SLIM (\"self-consistently interception model\") utiliza os conceitos mais recentes da física das descargas para a análise dos processos de formação e propagação do líder. Ao contrário dos demais modelos, o SLIM possibilita que se leve em conta a geometria tridimensional da estrutura. O modelo foi validado com base em comparações entre valores de campo elétrico para estabilização do líder em função da altura calculados e medidos em experimentos utilizando a técnica de descargas provocadas por foguetes, tendo-se obtido excelente concordância entre os resultados. Este trabalho destaca os aspectos mais importantes do SLIM e apresenta uma análise comparativa do mesmo com outros modelos bastante conhecidos, como o Modelo Eletrogeométrico, o Modelo de Eriksson e o Modelo de Rizk, além do procedimento simplificado recomendado pelo Guia IEEE Std. 1243. A análise é feita em termos da distância e do raio de atração, do número de descargas incidentes em uma linha de transmissão e do desempenho da mesma frente a descargas atmosféricas, discriminando as taxas de falhas causadas por falha de blindagem e por \"backflashover\". / In general, about 20 % to 60 % of the electric power service interruptions of distribution lines are attributed to lightning. For transmission lines, a typical figure is 70 %. The appraisal of the lightning performance of a power line is related to its mean flash collection rate, which depends on the mean ground flash density of the region and on the line exposure to direct lightning strokes. Models of different degrees of complexity are found in the literature for the estimation of lightning striking distances of objects and structures. However, besides the oversimplifications of the physical nature of the lightning discharge on which most of the models are based, till recently the tridimensional structure configuration could not be considered. This is an important limitation, as edges and other details of the object affect the electric field and, consequently, the upward leader initiation. Within this context, the self-consistently interception model (SLIM) proposed in 2006 by Becerra and Cooray is state-of-the-art leader inception and propagation leader model based on the physics of leader discharges which, unlike the other existing models, enables the tridimensional geometry of the structure to be taken into account. For the validation of the model, data obtained in rocket-triggered lightning experiments were used and an excellent agreement was found between measured and calculated leader stabilization electric fields as a function of the height of the rocket. This work describes the most important aspects of the new model and presents a comparative analysis of SLIM and other well-known model such as the Electrogeometric Model (EGM), Erikssons Model, and Rizks Model, as well as the simplified procedure recommended by IEEE Std. 1243. The analysis is done in terms of the striking distance, attractive radius, and the flash collection rate of a transmission line, as well as on its lightning performance, discriminating between the failure rates caused by shielding failure and backflashover.
24

O modelo SLIM (\"Self-Consistently Interception Model\") para estimativa da incidência de descargas atmosféricas em estruturas - avaliação e aplicação na análise do desempenho de linhas de transmissão de energia / The Self-consistently Interception Model (SLIM) for estimating the lightning incidence to structures evaluation of the model and application to the analysis of lightning performance of power transmission lines

Silva Neto, Acácio 19 April 2012 (has links)
O desempenho de uma linha de transmissão de energia está diretamente ligado ao número médio anual de descargas que nela incidem, o qual depende da densidade média de descargas ao solo na região e também do grau de exposição da linha. Modelos com diferentes graus de complexidade são encontrados na literatura para a estimativa da área de atração de estruturas a descargas atmosféricas. Entretanto, além das grandes simplificações sobre a física das descargas nas quais a maioria desses modelos se baseia, até recentemente não era possível considerar a configuração tridimensional das estruturas. Essa é uma limitação importante, pois detalhes do objeto afetam o campo elétrico e, consequentemente, o processo de formação do líder ascendente. Nesse contexto, o modelo desenvolvido em 2006 por Becerra e Cooray - SLIM (\"self-consistently interception model\") utiliza os conceitos mais recentes da física das descargas para a análise dos processos de formação e propagação do líder. Ao contrário dos demais modelos, o SLIM possibilita que se leve em conta a geometria tridimensional da estrutura. O modelo foi validado com base em comparações entre valores de campo elétrico para estabilização do líder em função da altura calculados e medidos em experimentos utilizando a técnica de descargas provocadas por foguetes, tendo-se obtido excelente concordância entre os resultados. Este trabalho destaca os aspectos mais importantes do SLIM e apresenta uma análise comparativa do mesmo com outros modelos bastante conhecidos, como o Modelo Eletrogeométrico, o Modelo de Eriksson e o Modelo de Rizk, além do procedimento simplificado recomendado pelo Guia IEEE Std. 1243. A análise é feita em termos da distância e do raio de atração, do número de descargas incidentes em uma linha de transmissão e do desempenho da mesma frente a descargas atmosféricas, discriminando as taxas de falhas causadas por falha de blindagem e por \"backflashover\". / In general, about 20 % to 60 % of the electric power service interruptions of distribution lines are attributed to lightning. For transmission lines, a typical figure is 70 %. The appraisal of the lightning performance of a power line is related to its mean flash collection rate, which depends on the mean ground flash density of the region and on the line exposure to direct lightning strokes. Models of different degrees of complexity are found in the literature for the estimation of lightning striking distances of objects and structures. However, besides the oversimplifications of the physical nature of the lightning discharge on which most of the models are based, till recently the tridimensional structure configuration could not be considered. This is an important limitation, as edges and other details of the object affect the electric field and, consequently, the upward leader initiation. Within this context, the self-consistently interception model (SLIM) proposed in 2006 by Becerra and Cooray is state-of-the-art leader inception and propagation leader model based on the physics of leader discharges which, unlike the other existing models, enables the tridimensional geometry of the structure to be taken into account. For the validation of the model, data obtained in rocket-triggered lightning experiments were used and an excellent agreement was found between measured and calculated leader stabilization electric fields as a function of the height of the rocket. This work describes the most important aspects of the new model and presents a comparative analysis of SLIM and other well-known model such as the Electrogeometric Model (EGM), Erikssons Model, and Rizks Model, as well as the simplified procedure recommended by IEEE Std. 1243. The analysis is done in terms of the striking distance, attractive radius, and the flash collection rate of a transmission line, as well as on its lightning performance, discriminating between the failure rates caused by shielding failure and backflashover.
25

Interventions to Mitigate the Effects of Interruptions During High-risk Medication Administration

Prakash, Varuna 13 January 2011 (has links)
Research suggests that interruptions are ubiquitous in healthcare settings and have a negative impact on patient safety. However, there is a lack of solutions to reduce harm arising from interruptions. Therefore, this research aimed to design and test the effectiveness of interventions to mitigate the effects of interruptions during medication administration. A three-phased study was conducted. First, direct observation was conducted to quantify the state of interruptions in an ambulatory unit where nurses routinely administered high-risk medications. Secondly, a user-centred approach was used to design interventions targeting errors arising from these interruptions. Finally, the effectiveness of these interventions was evaluated through a high-fidelity simulation experiment. Results showed that medication administration error rates decreased significantly on 4 of 7 measures with the use of interventions, compared to the control condition. Results of this work will help guide the implementation of interventions in nursing environments to reduce medication errors caused by interruptions.
26

Interventions to Mitigate the Effects of Interruptions During High-risk Medication Administration

Prakash, Varuna 13 January 2011 (has links)
Research suggests that interruptions are ubiquitous in healthcare settings and have a negative impact on patient safety. However, there is a lack of solutions to reduce harm arising from interruptions. Therefore, this research aimed to design and test the effectiveness of interventions to mitigate the effects of interruptions during medication administration. A three-phased study was conducted. First, direct observation was conducted to quantify the state of interruptions in an ambulatory unit where nurses routinely administered high-risk medications. Secondly, a user-centred approach was used to design interventions targeting errors arising from these interruptions. Finally, the effectiveness of these interventions was evaluated through a high-fidelity simulation experiment. Results showed that medication administration error rates decreased significantly on 4 of 7 measures with the use of interventions, compared to the control condition. Results of this work will help guide the implementation of interventions in nursing environments to reduce medication errors caused by interruptions.
27

CAREER INTERRUPTIONS: WAGE AND GENDER EFFECTS

Kearns, Jill 01 January 2010 (has links)
This dissertation examines the effects of career interruptions on workers’ wages. In chapter four I examine whether controlling for the type of interruption differently affects men’s and women’s wages and therefore can be used to explain the remaining gender wage differences. The increased participation of married women in the labor force has increased their wages from just 30% of men’s wages in 1890 to nearly 80% as of 2001. Thus, although the gender wage gap has narrowed over time, it has yet to be eliminated. One argument for the persistence of the gender wage gap is that previously researchers have used poor measures of experience to estimate men’s and women’s wages. Although previous studies have made strides in measuring experience, including controls for the timing of work experience, the gender wage gap persists. I extend the wage-gap literature by including controls for the types of interruptions men and women encounter. Because they typically experience different types of interruptions, I examine whether the varying types affect wages differently. I control for the types of interruptions and find similar effects for men’s and women’s wages. My study shows that types of job interruptions do not explain the remaining wage differentials. The fifth chapter extends from the fourth chapter by including controls for all periods of unpaid leave from work. I examine whether wage differences exist between workers who return to their current employer post-interruption versus those who change employers post-interruption. I find differences in the wage effects from different types of unpaid leave for men and women. Chapter six extends from previous chapters by including controls for all periods of paid leave from work in addition to unpaid leaves from work. I examine whether depreciation effects occur when women spend time out of work but receive compensation through paid maternity leaves. I find no evidence that time out of work because of paid maternity leaves depreciates skills.
28

Uma metodologia de anÃlise econÃmica dos serviÃos de atendimento emergencial ao consumidor de energia elÃtrica: estudo do caso do Cearà / A methodology for an economic perfomance analysis of customerâs emergency attendance services of electrical supply company in Ceara State.

Breno Dilherman Botelho 17 August 2010 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As interrupÃÃes no fornecimento de energia elÃtrica provocam diversos prejuÃzos econÃmicos Ãs concessionÃrias e aos seus clientes cuja extensÃo està associada, principalmente, à freqÃÃncia e duraÃÃo do evento e ao tipo de consumidor. Para as concessionÃrias de distribuiÃÃo de energia elÃtrica, que sÃo fiscalizadas pelos ÃrgÃos reguladores e pela sociedade, o grande desafio à a diminuiÃÃo do tempo das interrupÃÃes e, conseqÃentemente, das perdas econÃmicas por elas ocasionadas. Este trabalho apresenta a concepÃÃo e aplicaÃÃo de uma metodologia de anÃlise de desempenho econÃmico dos serviÃos de atendimento emergencial ao consumidor de energia elÃtrica, considerando os impactos econÃmico-financeiros para a distribuidora e para os consumidores de se utilizar um sistema de gestÃo operacional que otimize os parÃmetros que medem este desempenho. No estudo de caso, efetuado sobre o sistema de atendimento emergencial (SAE) da Companhia de Eletricidade do Cearà â COELCE, tem-se como parÃmetro principal de desempenho a duraÃÃo equivalente da interrupÃÃo (DEC), definida pela AgÃncia Nacional de Energia ElÃtrica - ANEEL. Partindo-se do uso de um sistema computacional de gestÃo otimizadora, desenvolvido na Universidade Federal do Cearà (Sistema SAEDE), o qual otimiza o despacho e a alocaÃÃo das equipes de campo responsÃveis pelos serviÃos de reparo na rede elÃtrica, aplicou-se a metodologia proposta no intuito de verificar se haveria benefÃcios justificÃveis para investimentos em sistemas de gestÃo operacional do SAE tanto para a distribuidora quanto para os consumidores. Os principais resultados obtidos atravÃs da aplicaÃÃo da metodologia ao SAE da COELCE apontou que a utilizaÃÃo do Sistema SAEDE contribui para reduzir custos aos usuÃrios devidos Ãs falhas na entrega de energia pela Companhia e, tambÃm, diminui custos a ela imputados quando ocorrem distÃrbios na rede elÃtrica. / Interruptions in electrical supply system normally cause several economic damages both to supplier companies and to their customers which are hard to be estimated. The extension of these damages is a function of the frequency and duration of the blackout and it varies according to the consumerâs characteristics. In Brazil, electrical supplier companies are regulated by federal and state agencies on behalf of the consumers and their major challenge is to reduce breakdown time and consequent economic losses. This work presents the conception and application of a methodology to make the economic performance assessment of customerâs emergency attendance services, according to the parameters and standards set by the Federal Regulatory Agency (ANEEL) and focusing both the supplier and consumers costs related to system breakdown. The proposed methodology was applied to the case of a electrical distribution company in Ceara State, in the northeastern Brazil, to which an optimized operational management system (SAEDE System) was built. SAEDE System is a computational tool that was developed to optimize the dispatch and the staffing of the emergency attendance teams who are employed to repair electrical fails in the regional system. The proposed methodology was applied to search the benefits of investments derived from using SAEDE System in customerâs emergency attendance services of electrical supply Company in Ceara State. Main results of the study point out that the application of SAEDE System contributes to reduce both customerâs costs as well as company costs related to electrical system breakdown in the study area.
29

Too much information! : Information-overload from an IT-management perspective

Mähler, Viktor January 2016 (has links)
As workplaces have become more digitalized and improvements constantly being made in order to optimize performance, it becomes pivotal for managers to understand how stress within organizations can be linked to the information- and communication technology within them. This thesis addresses the research gap of several studies existing regarding technology-related stress, but where a majority of them are quantitative in nature and overlooking the important aspect of organizational culture. The purpose of this thesis is to create an understanding regarding how managers perceive technostress in their organization, and how counterstrategies, if any, are applied. The added value of this research is that it highlights how poorly understood the problem of information overload is amongst certain managers, while highlighting the cultural aspects within organizations and their contributions to the problem. The results show that while many aspects related to information overload are noticed by managers and employees alike, very few – if any – counterstrategies exists in order to highlight and combat the problems that information overload entails. While individual practices existed, few could be realized at an organizational level without first addressing company culture.
30

Conception d’un embrayage de dérivation du couple à courants de Foucault pour les transmissions manuelles automatisées sans interruption de couple dans les véhicules à motorisation électrique ou hybride

Pouliot, Gabriel January 2015 (has links)
Les voitures électriques ont peu d’énergie embarquée pour se mouvoir comparativement aux véhicules thermiques. Il est donc important d’optimiser l’efficacité de la chaîne de traction pour maximiser la distance parcourue entre les recharges. Ces voitures utilisent un ratio simple pour coupler le moteur aux roues de la voiture. Le remplacement du ratio simple par une transmission à plusieurs vitesses dans une voiture électrique améliore l’efficacité du système de propulsion. Cependant, l’introduction d’une transmission à plusieurs ratios ne doit pas seulement améliorer l’efficacité énergétique pour recevoir l’acceptabilité du marché. Elle doit aussi offrir un confort de conduite similaire au ratio simple. L’ajout d’un embrayage de déviation du couple à la transmission manuelle permet de réduire ou d’éliminer les interruptions de celui-ci lors du passage des ratios. Cependant, les technologies d’embrayages à friction secs et humides ne sont pas bien adaptées à cette tâche de déviation du couple cependant. D’abord, l’embrayage est ouvert la majeure partie du temps ce qui fait en sorte qu’un embrayage humide aurait de grandes pertes visqueuses. Ensuite, les moteurs électriques tournent rapidement (11 000 révolutions par minute). Cela fait en sorte que l’embrayage dissipe de grandes quantités de chaleur pour ralentir le moteur avant l’engagement du prochain ratio. Un embrayage sec ne contient pas d’huile pour aider à l’extraction de la chaleur et ses bandes de friction s’usent rapidement sous ces conditions. Ce travail de maîtrise propose d’utiliser un embrayage électromagnétique plutôt qu’un embrayage à friction pour dévier le couple moteur. La démarche de conception d’un tel embrayage est présentée. Premièrement, un modèle analytique simple sert à déterminer les dimensions physiques de l’embrayage pour qu’il développe un certain couple électromagnétique. Ce requis provient des spécifications techniques d’une plateforme véhiculaire électrique disponible à l’Université de Sherbrooke (Projet Phoebus). Deuxièmement, des études par éléments finis des champs magnétiques de l’embrayage servent à valider que l’embrayage produit le niveau de couple désiré. L’embrayage est finalement testé dans une transmission manuelle automatisée installée sur un banc de test dynamométrique. Des changements de ratios sans interruption de couple démontrent la viabilité de l’embrayage à courants de Foucault en tant qu’embrayage de déviation du couple.

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