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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.
591

Étude pilote randomisée évaluant une intervention infirmière de mentorat d’aidants familiaux pour gérer le délirium post-chirurgie cardiaque

Mailhot, Tanya 06 1900 (has links)
Le délirium est un état confusionnel aigu se manifestant entre autres par de l’agitation, de la léthargie (APA, 2013). Le délirium survient chez près de la moitié des patients subissant une chirurgie cardiaque malgré les interventions de prévention basées sur des guides de pratique clinique (Gosselt et al., 2015). Les complications associées au délirium sont importantes incluant une augmentation de la durée de séjour et un ralentissement du rétablissement (Inouye, Wastendrop & Saczynski, 2013; Saczynski et al., 2012). Cette étude portait sur le développement et l’évaluation d’une nouvelle intervention infirmière de mentorat visant à faciliter la participation d’un aidant familial dans la gestion du délirium. L’étude portait également sur la validité d’une nouvelle mesure de monitoring du délirium, l’oxymétrie cérébrale. Le but principal de cette étude pilote randomisée était d’évaluer l’acceptabilité et la faisabilité du devis et de l’intervention infirmière de mentorat, ainsi que la validité de l’oxymétrie cérébrale. Le but secondaire était d’évaluer les effets préliminaires de l’intervention. Trente dyades comprenant un patient présentant un délirium post-chirurgie cardiaque et un aidant familial ont été assignées aléatoirement au groupe contrôle recevant les soins usuels ou au groupe recevant l’intervention infirmière. L’intervention, ancrée dans une approche caring, visait à faciliter la transition des aidants dans un rôle participatif auprès de leur proche atteint de délirium ainsi qu’à favoriser le rehaussement de leur sentiment d’efficacité personnelle. L’indicateur principal d’évaluation de l’acceptabilité du devis était l’obtention du consentement d’au moins 75% des aidants approchés pour participer à l’étude. Par la suite, l’acceptabilité et la faisabilité ont été évaluées en se basant sur des critères d’évaluation des études pilotes pour le devis, par exemple, sur des données de recrutement et du domaine de l’évaluation d’interventions infirmières pour l’intervention, par exemple, la satisfaction des participants. Les effets préliminaires de l’intervention pour les patients ont été mesurés au moyen d’un score de sévérité du délirium, du nombre de complications, de la durée du séjour et du rétablissement psychofonctionnel. Auprès des aidants, des scores d’anxiété et d’efficacité personnelle ont été obtenus. Afin de tester la validité de la nouvelle mesure, les valeurs d’oxymétrie cérébrale ont été comparées à des scores de trois échelles d’évaluation du délirium validées. L’indicateur principal d’acceptabilité du devis, a été atteint avec un taux de consentement chez les aidants de 76,9 %. Cependant, le recrutement s’est avéré un grand défi, principalement parce que la prévalence des délirium détectés fut moindre qu’anticipée. L'intervention était acceptable et réalisable, comme en témoigne la participation des aidants familiaux. Les résultats de sévérité du délirium se sont avérés similaires dans les deux groupes, tout comme ceux relatifs aux complications. Les autres mesures de résultats ont présenté une tendance favorisant le groupe intervention dont une durée d’hospitalisation plus courte ainsi qu’un niveau d’anxiété moindre et d’un niveau sentiment d’efficacité personnelle plus élevé chez les aidants. Un effet statistiquement significatif de l’intervention favorisant le groupe intervention a été observé sur le rétablissement psychofonctionnel (p = 0,01). Une relation statistiquement significative entre les valeurs d’oxymétrie cérébrale et la présence et la sévérité du délirium a été observée (p ≤ 0,001). Cette étude contribue à l’avancement des connaissances par la démonstration de l’acceptabilité et la faisabilité d’une intervention pour rehausser la gestion du délirium par un mentorat des aidants familiaux. Une autre contribution réside dans les résultats prometteurs quant à la validité de l’oxymétrie cérébrale comme nouvelle mesure de monitoring du délirium qui pourra rehausser la détection et la gestion du délirium. / Delirium is an acute confusional state accompanied by agitation or lethargy (APA, 2013). Despite the prevention strategies based on clinical practice guidelines, nearly half of the patients undergoing a cardiac surgery will present delirium (Gosselt et al., 2015). Complications of delirium are important and include increased length of stay in addition to a slower recovery (Inouye, Wastendrop & Saczynski, 2013; Saczynski et al., 2012). This study focused, on a new nursing intervention aiming to facilitate participation from a family caregiver in the management of delirium. The study also focused on the validity of a new measure to monitor delirium, cerebral oximetry, a non-invasive measure potentially able to indicate the presence and severity of the delirium. The primary objective of the randomized pilot study was to assess the acceptability and feasibility of the design and nursing interventions, and the validity of cerebral oximetry to monitor delirium. The secondary objective was to assess the preliminary efficacy of the intervention. Thirty dyads including a patient who had post-cardiac surgery delirium and a family caregiver were randomly assigned to either the control group receiving the usual care or a group receiving the experimental nursing interventions. The intervention, rooted in a caring approach, aimed to facilitate family caregivers’ transition to an involved role in delirium management in addition to promoting the enhancement of their self-efficacy. The primary indicator to assess the acceptability of the design was the consent of at least 75 % of family caregivers who were approached to participate in the study. Afterwards, the acceptability and feasibility was were evaluated based on criteria in the field of pilot studies for the study design, for example, on recruitment data, and on criteria in the field of evaluation of nursing interventions for the intervention, for example, the satisfaction of the caregivers . The preliminary effects of the intervention of the patients were measured using a score reflecting delirium severity, the amount of postoperative complications as well as the length of hospital stay and patient’s psycho-functional recovery. Scores for anxiety and self-efficacy were also obtained from the caregivers. In order to test the validity of the new measure of delirium, cerebral oximetry values were compared to scores on three validated delirium rating scales. The primary indicator of the acceptability estimate was achieved with a 76.9 % consent rate among caregivers. However, recruitment has sown itself to be a great challenge, mainly because the number of eligible patients was less than anticipated. The experimental intervention was acceptable and feasible, as evidenced by the participation of the caregivers. Results on delirium severity and complications were similar in the two groups. Results favoring the intervention groups included shorter length of stay and less anxiety along with the added feeling of greater personal effectiveness among caregivers. In addition, a statistically significant effect of the intervention was observed on the psycho-functional recovery favoring the intervention group. (p=0.01). A statistically significant relationship between cerebral oximetry and occurrence and severity of delirium was observed (p ≤ 0.001), supporting the potential of this measure in monitoring the delirium. This study contributes to the advancements of knowledge through the demonstration of the acceptability and feasibility of an intervention to enhance the management of delirium by mentoring caregivers. Another contribution lies in the promising results on the validity of cerebral oximetry as a new monitoring measure of delirium, which has the potential of enhancing delirium detection and management.
592

Self-rated health and respiratory symptoms among civil aviation pilots : Occupational and non-occupational risk factors

Fu, Xi January 2017 (has links)
There is concern about the indoor environment in aircraft but few stud-ies exist on self-rated health (SRH) and respiratory symptoms among pilots. Occupational and non-occupational risk factors for SRH, respira-tory symptoms and other symptoms among commercial pilots were investigated in this thesis. One cohort study and one prevalence study were performed among pilots in one Scandinavian airline company. Fungal DNA, furry pet allergens and volatile organic compounds of microbial origin (MVOC) were measured on board. Cat (fel d1), dog (Can f1) and horse (Ecu cx) allergens were found in all dust samples and allergen levels were 27-75 times higher in aircraft with textile seats as compared to leather surfaces. The sum of MVOCs in the cabin air was 3.7 times higher than in homes in Uppsala and 2-methyl-1-butanol and 3-methyl-1-butanol concentrations were 15-17 times higher. Asper-gillus/Penicillium DNA and Aspergillus versicolor DNA were more common in aircraft with textile seats. One fifth reported SRH as poor or fair, 62% had fatigue, 46% overweight/obesity and 71% insomnia. Poor or fair SRH was associated with overweight/obesity, lack of exercise, insomnia, low sense of coherence (SOC) and high work demand. Re-covery from work was worse among those with insomnia and low social support at work. Fatigue was more common among young or female pilots and related to insomnia and high work demand. Pilots flying MD80 or Saab 2000 aircraft had less fatigue. Pilots exposed to environmental tobacco (ETS) on board had more eye symptoms and fatigue which were reduced after the ban of smoking (in 1997). Pilots with increased work demand developed more rhinitis, dermal symptoms and fartigue and those with decreased work control developed more eye symptoms. The incidence of doctors’ diagnosed asthma and atopy were 2.4 and 16.6 per 1000 person years, respectively. Pilots changing type of flight got more airway infections. Those reporting decreased work control had a higher incidence of atopy. Risk factors in the home environment included ETS, dampness or mould, window pane condensation in winter and living in houses built after 1975. In conclusion, SRH and respiratory health among pilots are associated with specific occupational and non-occupational risk factors.
593

Etude et modélisation de méthodes de séparation du méthane et de H2S, sélection d'une méthode favorisant la valorisation de H2S / Study and modeling of separation methods H2S from methane, selection of a method favoring H2S valorization

Cherif, Hamadi 08 December 2016 (has links)
Le biogaz doit être purifié pour devenir un combustible renouvelable. De nombreux traitements actuels ne sont pas satisfaisants car, pour des raisons de coûts les procédés de séparation privilégiés aboutissent souvent au rejet direct ou indirect du sulfure d'hydrogène (H2S) à l’atmosphère, c’est le cas de la séparation à l’eau sous pression. Les objectifs de la thèse portent d’abord sur l’étude et la modélisation des méthodes connues de séparation de l'hydrogène sulfuré du méthane. Les concentrations typiques varient de 200 à 5000 ppm, et la séparation devra réduire la teneur résiduelle en H2S à moins de 1 ppm. Parallèlement seront étudiées les méthodes de traitement de H2S. Une fois la (ou les) méthode(s) de séparation sélectionnée(s), des essais de validation seront effectués sur un système traitant de l’ordre de 85 Nm3/h de méthane où seront injectées des quantités de H2S variant entre 1 et 100 ppm.Cette thèse requiert des modélisations réalistes sous Aspen Plus® ou sous un code équivalent pour établir a priori des efficacités de séparation selon différentes conditions opératoires et en prenant en compte le paramètre température. L’énergie dépensée pour la séparation effective sera un des critères fort de la comparaison, de même que l’économie de matière.Une approche système est indispensable pour étudier la rétroaction de la méthode de valorisation du H2S sur la ou les méthodes séparatives. A priori c’est aussi l’outil Aspen Plus® ou équivalent qui permettra cette approche système.L’étude du procédé sera menée selon la double approche modélisation et expérimentation, pour l’étude expérimentale des méthodes séparatives, l’échelle du banc sera semi-industrielle et le banc permettra d’étudier les méthodes de séparation jusqu’à -90°C. / Biogas must be purified for becoming a renewable fuel. At now, the most part of the purification techniques are not satisfactory because they imply hydrogen sulfides (H2S) rejection to the atmosphere. One example of these methods is the treatment with high pressure water. The first objective of the thesis is modeling the conventional methods for separating H2S from methane. Typical concentrations of H2S in methane vary from 200 to 5000 pm. Separation methods must decrease the concentration of H2S in methane to less than 1 ppm. At the same time, methods for H2S treatment will be studied.Once the most appropriated separation methods will be selected, some test will be carried out on a pilot plant capable of treating 85 Nm3/h of methane, where quantities of H2S ranging from 1 and 100 ppm will be injected. These tests will allow validating the modeling of the separation process. On the basis of the obtained results, a specific test bench will be conceived and constructed for validating the selected process.The thesis work requires simulating the separation process using the software Aspen Plus® or an equivalent one. The effectiveness of different operative conditions will be tested, varying also the parameter temperature. The energy necessary for the separation will be one of the most important criteria for the comparison, as well as the mass consumption of the different fluids involved in the process.A system approach is fundamental for evaluating the backward effect of the H2S valorization method on the separation techniques. The process simulator (Aspen Plus® or equivalent) will allow the system approach.The study will involve modeling and experimental parts. The experimental part will be carried out taking advantage of a semi-industrial size test bench, allowing studying the separation methods down to -90°C.
594

Istanbul viewed : the representation of the city in Ottoman maps of the sixteenth and seventeenth centuries

Orbay, İffet January 2001 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001. / Includes bibliographical references (p. 361-395). / Starting from the premise that maps are essentially about visualizing space, this dissertation examines what the Ottoman maps of Istanbul reveal about the city's perception, as it evolved in connection to urban development after the conquest. The maps that form the subject of this study appear as illustrations in three manuscript books. The Istanbul maps contained in Mecmu'-i Menazil (1537-8) and HiinernAme (1584) respectively mark the beginning and the accomplishment of the city's architectural elaboration. The other twenty maps, featuring in manuscript copies of Kitab-i Bahriye (1520s), roughly span the period between 1550 and 1700. The variants of a design fixed around 1570 offer an image that fulfills its topographic elaboration in the late-seventeenth century. While the making of this map's design relates to Istanbul's sixteenth century urban development, its topographical elaboration reflects a new perception of the city. These picture-maps, produced in the sixteenth and seventeenth centuries, form a unique group of documents as the only known Ottoman pictorial representations showing the city as a whole. As revealed by the context of the books containing them, their making relates both to Ottoman Empire's territorial expansion and to the appropriation of Constantinople as its new capital. Their cartographic language combines, in different manners, the familiar conventions of Islamic miniature painting with artistic forms encountered and assimilated during territorial expansion, particularly in contact with Venice. / (cont.) Especially the making of the Istanbul maps in Kitfb-i Bahriye copies illustrates the crucial role of the Mediterranean seafaring culture, its navigation manuals, nautical charts and island books. These images of Istanbul can be related to the development of the urban landscape and its symbolic function. Their study as cartographic representations pays attention to both accuracy and emphasis in their topographic contents. Supported by contemporary European visual sources and travel accounts as well as Ottoman topographic and poetic descriptions of Istanbul, the viewing directions, the depictions of buildings, and the overall cartographic composition in these maps are interpreted as features shaping a symbolic landscape that developed from an ideal vision to an actual garden-like urban environment, structured by land, water, and architecture. / by İffet Orbay. / Ph.D.
595

Computer Aided Text Analysis in Personnel Selection

Garrad, Mark, n/a January 2004 (has links)
This program of research was aimed at investigating a novel application of computer aided text analysis (CATA). To date, CATA has been used in a wide variety of disciplines, including Psychology, but never in the area of personnel selection. Traditional personnel selection techniques have met with limited success in the prediction of costly training failures for some occupational groups such as pilot and air traffic controller. Accordingly, the overall purpose of this thesis was to assess the validity of linguistic style to select personnel. Several studies were used to examine the structure of language in a personnel selection setting; the relationship between linguistic style and the individual differences dimensions of ability, personality and vocational interests; the validity of linguistic style as a personnel selection tool and the differences in linguistic style across occupational groups. The participants for the studies contained in this thesis consisted of a group of 810 Royal Australian Air Force Pilot, Air Traffic Control and Air Defence Officer trainees. The results partially supported two of the eight hypotheses; the other six hypotheses were supported. The structure of the linguistic style measure was found to be different in this study compared with the structure found in previous research. Linguistic style was found to be unrelated to ability or vocational interests, although some overlap was found between linguistic style and the measure of personality. In terms of personnel selection validity, linguistic style was found to relate to the outcome of training for the occupations of Pilot, Air Traffic Control and Air Defence Officer. Linguistic style also demonstrated incremental validity beyond traditional ability and selection interview measures. The findings are discussed in light of the Five Factor Theory of Personality, and motivational theory and a modified spreading activation network model of semantic memory and knowledge. A general conclusion is drawn that the analysis of linguistic style is a promising new tool in the area of personnel selection.
596

Evaluation and Justification of an RFID Implementation : Pilot at IKEA Customer Distribution Centre

Larsson, Björn, Qviberg, Ola January 2004 (has links)
<p>The purpose of this final thesis isto develop a model for justification and evaluation of RFID technology. RFID is a new, relatively untested, technology using radio signals for automatic identification of different objects. Our theoretical frame of references focuses on research about RFID and implementation iss ues, we also conducted case studies and interviews in order to learn about RFID. Most RFID installations of today are Pilots or early adopters wanting to try new technology. A lot of the written sources were reports from consultancy firms or suppliers of technology. </p><p>Implementing RFID in real environment gave important insights into potentials and limitations of the technology. It proved that it is difficult to achieve sufficient readability in a steel environment. We also learned that one should not underestimate the time for installation and tuning in order to meet higher readability. The project finally resulted in an iterative model for justification and evaluation of RFID technology.</p>
597

Robustness versus performance tradeoffs in PID tuning

Amiri, Mohammad Sadegh 11 1900 (has links)
Proportional, integral and derivative (PID) controller tuning guidelines in process industry have been in place for over six decades. Nevertheless despite their long design history PID tuning has remained an ‘art’ and no single comprehensive solution yet exists. In this study various considerations, with new and different perspectives, have been taken into account in PID tuning design. This study explores the issue of PID tuning from a practical point of view with particular focus on robust design in the presence of typical problems in process industry: process changes, valve stiction effects and unmeasured disturbances. The IMC tuning rule is recommended for setpoint tracking, while in the case of regulation, a newly proposed tuning rule, based on a combination of IMC and Ziegler-Nichols method, is demonstrated to give satisfactory results. The results were evaluated by simulation and were also validated on a computer-interfaced pilot scale continuous stirred tank heater (CSTH) process. / Chemical Engineering
598

Evaluation and Justification of an RFID Implementation : Pilot at IKEA Customer Distribution Centre

Larsson, Björn, Qviberg, Ola January 2004 (has links)
The purpose of this final thesis isto develop a model for justification and evaluation of RFID technology. RFID is a new, relatively untested, technology using radio signals for automatic identification of different objects. Our theoretical frame of references focuses on research about RFID and implementation iss ues, we also conducted case studies and interviews in order to learn about RFID. Most RFID installations of today are Pilots or early adopters wanting to try new technology. A lot of the written sources were reports from consultancy firms or suppliers of technology. Implementing RFID in real environment gave important insights into potentials and limitations of the technology. It proved that it is difficult to achieve sufficient readability in a steel environment. We also learned that one should not underestimate the time for installation and tuning in order to meet higher readability. The project finally resulted in an iterative model for justification and evaluation of RFID technology.
599

Opportunities and uncertainties in the early stages of development of CO2 capture and storage

Lind, Mårten January 2009 (has links)
The topic of this thesis is carbon dioxide (CO2) capture and storage (CCS), which is a technology that is currently being promoted by industries, scientists and governments, among others, in order to mitigate climate change despite a continued use of fossil fuels. Because of the complex nature of CCS and the risks it entails, it is controversial. The aim of this thesis is to analyse how the technology may be further developed in a responsible manner. In the first part of the thesis different methods for capturing CO2 from industrial processes as well as power plants are analysed. The aim is to identify early opportunities for CO2 capture, which is considered important because of the urgency of the climate change problem. Three potential early opportunities are studied: i) capturing CO2 from calcining processes such as cement industries by using the oxyfuel process, ii) capturing CO2 from pressurised flue gas, and iii) capturing CO2 from hybrid combined cycles. Each opportunity has properties that may make them competitive in comparison to the more common alternatives if CCS is realised. However, there are also drawbacks. For example, while capturing CO2 from pressurised flue gas enables the use of more compact capture plant designs as well as less expensive and less toxic absorbents, the concept is neither suitable for retrofitting nor has it been promoted by the large and influential corporations. The second part of the thesis has a broader scope than the first and is multidisciplinary in its nature with inspiration from the research field of Science and Technology Studies (STS). The approach is to critically analyse stakeholder percep-tions regarding CCS, with a specific focus on the CCS experts. The thesis sheds new light on the complexity and scientific uncertainty of CCS as well as on the optimism among many of its proponents. Because of the uncertain development when it comes to climate change, fossil fuel use and greenhouse gas emissions, the conclusion is that CCS has to be further developed and demonstrated. A responsible strategy for a future development of CCS would benefit from: i) a search for win-win strategies, ii) increasing use of appropriate analytical tools such as life-cycle analysis, iii) a consideration of fossil fuel scarcity and increasing price volatility, iv) funding of unbiased research and v) increasing simultaneous investments in long-term solutions such as renewable energy alternatives and efficiency improvements. / QC 20100727
600

Renovating Sewage Effluent by Ground-Water Recharge

Bouwer, Herman, Lance, J. C., Rice, R. C. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / Sewage effluent is commonly used for the irrigation of crops that are not consumed raw. Due to continued population growth in the Salt River Valley, Arizona, economic reuse of municipal waste waters is becoming essential. The salt river bed has about 3 ft of fine loamy sand underlain by sand and gravel layers to great depth and a groundwater table at about 10 ft depth. These conditions are very favorable for high-rate waste water reclamation by groundwater recharge. The activated sludge plant in phoenix will probably be discharging 250 mgd by the year 2000. At 4.5 ft average annual water use, this could irrigate about 70,000 acres, possibly more than agriculture will need at that time. A sewage effluent renovation pilot project was located about 1.5 miles from the plant. It contains 6 parallel recharge basins 20 to 700 ft each, spaced 20 ft apart. The basins were covered by grass, gravel or were left bare. Observation wells were installed at various locations in the area. Results indicated that infiltration rates were fastest in the grassy basins. Phosphate, nitrogen and median fecal coliform levels were all lower after this form of tertiary treatment. Practical details of the application of this water reclamation method in the Salt River Valley are outlined. Costs would be 5 dollars/af, less than 1/10 the equivalent costs of in-plant tertiary treatments.

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