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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.
101

Level of nurses' competence in mechanical ventilation in intensive care units of two tertiary health care institutions in Gauteng

Botha, Margaret Lynn January 2012 (has links)
Thesis submitted in fulfillment of the requirements for the degree of Masters of Science in Nursing, Faculty of Community and Health Sciences, Department of Nursing Education, University of the Witwatersrand Johannesburg, 2012 / Studies generally agree the survival of the mechanically ventilated patient in the ICU is largely reliant upon the competence of the nurse undertaking this highly specialized role (Alphonso,Quinones,Mishra,et al. 2004; Burns 2005) However, an audit undertaken by the Critical Care Society of Southern Africa (2004) revealed that 75 % of nurses working in ICU are inexperienced and do not hold an ICU qualification, and as such are unlikely to have acquired the level of competency required to care for the mechanically ventilated patient (Binnekade 2004). A high index of suspicion exists around the competence levels of nurses‟ currently working in ICU in SA as revealed by local studies (Khoza & Ehlers 1998; Scribante & Bhagwanjee 2003; Moeti, van Niekerk, van Velden, 2004; Morolong & Chabeli 2005; Windsor 2005; Perrie & Schmollgruber 2010). The purpose of the study was to determine and describe the level of competence with regard to mechanical ventilation, of nurses working in ICU, who have varying years of experience and training backgrounds, using study specific designed clinical vignettes, in two tertiary healthcare institutions in Gauteng. A descriptive two phase design was utilized for the study. Phase one comprised the development and validation of three clinical vignettes to determine the level of competence of nurses working in ICU‟s with regard to mechanical ventilation. A modified Delphi technique technique using purposively sampled experts from medical technical and nursing backgrounds was used to validate the three clinical vignettes. Content validity was strengthened by computing CVI of the instrument. In Phase two consecutive sampling was used, and data collection comprised of participants (n=136) completing three validated clinical vignettes in the ICU‟s of two tertiary healthcare institutions in Gauteng. All nurses who participated in the study completed the same three clinical vignettes and demographic data. Nurses‟ perceptions regarding their own level of competence with regard to mechanical ventilation were quantified and compared with actual scores achieved in the clinical vignettes. Descriptive and inferential statistics were used to analyse the data. The level of significance was set at <0,05 and confidence levels at 95%. The competency indicator for the vignettes was set at 75% by the expert group, and nurses‟ level of competence was graded according to vignette score outcomes using a grading scale. Statistical assistance was obtained from a statistician from the Medical Research Council (MRC). Results: Results of the study showed that nurses regardless of training background, age, or experience showed a poor level of knowledge, the average score being 48% for ICU qualified nurses and 31% for non-ICU qualified nurses. There was a small significant difference between ICU qualified and non-ICU qualified nurses‟ competence levels in mechanical ventilation when analysed using a two tailed- t- test (p=0.039). Nurses also experienced a misperception regarding their own competence levels in mechanical ventilation when compared to their actual competence levels as determined by three clinical vignettes.
102

Energy systems for multifamily housing : an urban case study

Hale, Stephen Holmes January 1979 (has links)
Thesis. 1979. M.Arch.A.S.--Massachusetts Institute of Technology. Dept. of Architecture. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Includes bibliographical references. / by Stephen Hale. / M.Arch.A.S.
103

Wake survey behind a rotating ventilator

Rashid, Dewan Md. Harunur, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2002 (has links)
With environmental concern growing in both affluent and developing countries, roof top ventilators, a form of natural ventilation requiring only wind energy to ensure quality air circulation and comfort is becoming a considered choice of many households and industries. Unfortunately, however, many of these ventilators have evolved through trial and error and the flow physics associated with these ventilators is barely understood. The present experimental project was, therefore, undertaken as part of UNSW- Industry collaboration program funded under an Australian Research Council Grant to explore whether the aerodynamics forces acting on these ventilators during their operation could be obtained. A commercial roof top ventilator supplied by industry was, therefore, tested in an open jet wind tunnel of the University of New South Wales and the results are presented in this thesis. A novel feature of this project is the examination of the suitability of ???the three dimensional wake traverse??? technique to the wake of rotating ventilator. This technique has so far been applied with limited success to the wake of lifting bodies of fixed wing configuration only. In the absence of adequate data in the literature on rotating ventilator, the aerodynamics force components obtained by this technique have been compared against force balance measurements. The results show that the wake traverse technique is capable of determining lift and total drag forces associated with the ventilator flow during its operation from the pressure and velocity information gathered downstream of a ventilator in its wake. Generally, from these data, the technique also allows isolation of the profile and induced components of the drag force. However, from the induced drag value, while it is possible to determine the lift force, it is however, found that a more accurate value of lift force can be evaluated using axial vorticity formulation. The availability of the above technique which does not require measurements on the test specimen itself, will aid in providing a cost efficient investigation of the aerodynamic forces and consequently the performance of a roof top ventilator.
104

Evaluation de la convivialité de onze ventilateurs de domicile

Laplanche, Virginie. Gonzalez, Jésus January 2005 (has links) (PDF)
Thèse d'exercice : Médecine. Médecine générale : Paris 12 : 2005. / Titre provenant de l'écran-titre. Bibliogr. f. 51-52.
105

Étude de la procédure de sevrage de la ventilation liquidienne totale chez l'agneau nouveau-né à poumons sains

Rochon, Marie-Ève January 2012 (has links)
Le but de cette étude était d'étudier la procédure de sevrage de la ventilation liquidienne totale (VLT) au cours de laquelle deux types de perfluorocarbones (PFC), soit le Perfluorodecalin (PFDEC) et le Perflubron (PFOB) ont été utilisés et ce à l'aide d 'un modèle néonatal ovin. Méthodes : Dix agneaux nouveau-nés à terme étaient d'abord ventilés, anesthésiés et paralysés. Une instrumentation chirurgicale permettait un suivi des gaz artériels et d'index ventilatoires ainsi que de l'état hémodynamique p .. techniques de thermodilution (Pulsion Médical System, Allemagne). Puis, les agneaux étaient randomisés en deux groupes selon le type de PFC utilisé lors de la VLT, soit le PFDEC (F2 Chemicals, UK) (n=5) ou le PFOB (Fluoromed L.P., USA) (n=5). Pour les deux groupes, une VLT d 'une heure a été effectuée à l'aide de ces paramètres: Vt=25 mL/kg, FR=6,5/min, PEEP=1 cm H [indice inférieur 2] O. Puis, le passage en ventilation liquidienne partielle (VLP) se faisait en fin d 'expiration à l'aide de notre prototype Inolivent-4. Le Vt, la PEEP et la FiO[indice inférieur 2] étaient ensuite ajustés périodiquement pendant 12 h et une technique de succion était employée au besoin pour évacuer le mucus du tube endotrachéal. Principaux résultats : Lors de la VLT, les gaz artériels des agneaux ventilés avec le PFOB et avec le PFDEC étaient comparables. Par contre, une baisse de la pression artérielle systémique moyenne (APm) et de la pression pulmonaire artérielle moyenne (PAPm) ont été notées dans le groupe PFDEC. Lors du sevrage de la VLT, les pressions de ventilation étaient plus basses dans le groupe PFOB, mais sans autre différence statistiquement significative. La ventilation alvéolaire était normale dans les deux groupes, mais l'oxygénation s 'est graduellem ent détériorée. Les analyses histologiques ont démontré une bonne préservation de l'architecture pulmonaire globale. Conclusions : Le sevrage de la VLT chez des sujets sains a été effectué en préservant une bonne ventilation alvéolaire, mais avec un niveau d'oxygénation se dégradant au cours des 12h de sevrage et ce peu importe le type de PFC utilisé. Notre hypothèse principale serait une anomalie du rapport ventilation/perfusion lors de la phase de sevrage. Par ailleurs, la phase de VLT a été plus efficace lorsque PFOB était em ployé comparativement au PFDEC.
106

Utvärdering av arbetsmiljön på en träbränslemottagning : En studie om spridning av trämögelsporer / Evaluation of the work environment at a wood fuel reception : A study of the spread of wooden mold spores

Svensson-Höök, Anders January 2015 (has links)
Karlstads Energi AB:s vågstation vid Hedenverket i Karlstad är en anläggning där invägning och analys av träbränsle utförs. Provtagning och hantering av träbränsle hör till de dagliga arbetsuppgifterna för personalen. Vid nära hantering av trämaterial finns risken att exponeras för trämögelsporer. Exponering av mikrobiologiska luftföroreningar kan orsaka hälsobesvär på lungor och luftvägar hos människor. Efter utförd riskbedömning av vågstationen noterades en oro att trämögelsporer och dammpartiklar sprids bortom lokalen för provtagning av träbränsle till andra utrymmen. Bedömningen talar för att ventilationen kanske är bristfällig och inte är anpassad för den aktuella verksamheten. Potentiell spridning av trämögelsporer via hantering, undermålig städning samt via kläder och annan utrustning tillhörde även problematiken. Syftet med detta arbete var att vid provtagningen av träbränsle förtydliga spridning och exponering av luftburna trämögelsporer i arbetsmiljön. Detta med avsikt att identifiera områden och arbetsrutiner där förebyggande åtgärder mot spridning av trämögelsporer kunde införas. Målet var att definiera luftrörelser i lokalen till följd av arbetsrutiner och ventilation. Resultatet från undersökningen fungerade som ett underlag för utvärdering av åtgärder mot spridning och exponering av trämögelsporer. Genom mätningar och observationer kunde luftrörelser och föroreningskällor identifieras. Mätningar avsåg luftens temperatur och hastighet i lokalen. Ventilationen undersöktes genom observation av luftrörelser och inventering av ventilationsutrustning. Arbets- och skyddsrutiner observerades utan social interaktion från observatören. Resultat från mätningar och observationer analyserades och jämfördes med riktvärden presenterade i litteratur, forskningsarbeten samt Arbetsmiljöverkets föreskrifter. Ventilationen i lokalen för provtagning av träbränsle konstateras vara bristfällig för pågående verksamhet. Spridning och exponering av hälsofarliga trämögelsporer utgörs av bristen på tillräcklig processventilation, långa horisontella luftflöden, stillastående luft och cirkulerande av förorenad luft. Observation av arbets- och skyddsrutiner visar på bristande inneslutning av föroreningskällor. Det är även dålig användning av personlig skyddsutrustning samt genomförande av städning. Utifrån resultaten kunde flera förebyggande åtgärder föreslås. Införande av processventilation och reformering av ventilationssystem skulle leda till mindre spridning av trämögelsporer och bättre luftutbyte av lokalen. En granskning av arbets- och skyddsrutiner liksom införande av nya rutiner med en medvetenhet om trämögelsporers förmåga att spridas via luften föreslogs som åtgärd mot exponering. / Karlstads Energi AB's weighing station at Hedenverket in Karlstad is a facility where weighing and analysis of wood fuel are carried out. Sampling and handling of wood fuel is one of the daily duties for the staff at the weigh station. At the close management of wooden material there is a risk of exposure to airborne mold spores. Exposure to microbiological air pollution may cause health problems in the lungs and airways of humans. After performing the risk assessment at the weighing station there was concerns that mold spores and dust particles spread beyond the premises for the sampling of wood fuel to other areas. The assessment indicates that the ventilation may be inadequate and is not adapted to the current work environment. Potential spread of mold spores through handling, poor housekeeping and by clothing and other equipment also belonged to the uncertainties. The aim with this study was by the sampling of wood fuel to clarify the dispersion and exposure to airborne mold spores in the work environment. This is with the intention to identify areas and work routines where preventive measures against the spread of mold spores could be introduced. The goal was to define the air movement within the premises of wood fuel sampling as a result of working practices and ventilation. The results of the study served as a basis for the evaluation of measures against the spread and exposure of mold spores. By measurements and observations the air movements and sources of contamination within the premises could be identified. Measurements relate to the air temperature and air velocity within the premises. The ventilation was investigated by observation of air movement and taking inventory of the ventilation equipment. Work and protective practices were observed without any social interaction by the observer. Results of measurements and observations were analyzed and compared to guidelines presented in literature, research works and the Swedish Work Environment Authority's constitution. The ventilation of the premises for the sampling of wood fuel was found to be flawed for the current work environment. The dispersion and exposure to hazardous mold spores is the lack of sufficient exhaust ventilation, long horizontal air flow, stagnant air and circulating of contaminated air. Observations of work and protective procedures show an insufficient containment of pollution sources. It is also poor use of protective equipment and carrying through with cleaning. Based on the results could several preventative measures be proposed. Introduction of additional exhaust ventilation and reforming of the ventilation system would result in less spread of mold spores and a better air exchange of the premises. A review of work and protective procedures as well as introducing of new procedures with an awareness of mold spores ability to spread via air was suggested as a measure against exposure.
107

Energianalys av fastighet Brynäs 12:1 : Energikartläggning med effektiviseringsåtgärder inriktning mot ventilation

Blomqvist, Sofia, Sundby, Dennis January 2014 (has links)
Energianvändningen i Sverige och världen förväntas öka och bostads- och servicesektorn står för 40 % av världens totala energibehov. Det är viktigt att energieffektivisera redan befintliga byggnader och optimera dess system då en lägre energianvändning gynnar både miljön och ekonomin. En byggnads ventilationssystem står för en stor del av en fastighets energianvändning och det finns ofta stor potential för systemet att optimeras och effektiviseras. En fastighetsägare vill inte ha fastigheter som står outhyrda. Outhyrda lokaler betyder minskade intäkter i hyror och i vissa fall tillkommer energianvändning för de tomma lokalerna i form av uppvärmning och ventilation som fastighetsägaren måste betala. System som helt kan stängas av eller styras beroende på ventilationsbehov behövs för att den sistnämnda kostnaden ska reduceras helt under tiden lokalen är outhyrd och för att den totala energianvändningen ska minska när en hyresgäst flyttar in. Ventilationens syfte är att ventilera bort fukt, värme, partiklar och koldioxid så att ett bra inomhusklimat skapas för de personer som vistas i byggnaden. Den vanligaste ventilationsprincipen för offentliga byggnader är att ventilera luft med ett konstant luftflöde genom ett constant air volume-system. Med behovsanpassad ventilation i form av ett variable air volume-system kan stora besparingar göras då man anpassar luftflödet efter det verkliga ventilationsbehovet istället för att ventilera byggnaden med ett konstant maxflöde. En installation av ett VAV-system i form av CO2- eller närvarostyrning sänker ventilationens energianvändning samtidigt som kvaliteten på inomhusmiljön bibehålls. Arbetet som har utförts innefattar en energikartläggning av fastigheten Brynäs 12:1 då en energikartläggning hjälper till att förstå en byggnads energianvändning och identifierar möjliga energisparåtgärder. Energianvändningen för fastighetens delsystem har kartlagts och analyserats för att ta fram förslag på besparingsåtgärder. Resultatet av energikartläggningen visade att det fanns stor besparingspotential för ventilationsaggregat TA1, TA2 och TA3:s el- och värmeanvändning. Om de åtgärder rörande ventilationen som presenteras i arbetet som till exempel flödes- och tidsreducering vidtas kan en energibesparing på 333 MWh/år uppnås, vilket är 28 % av fastighetens totala årliga energianvändning. / Energy use in Sweden and the world is expected to increase and the residential and services account for 40% of total world energy demand. It is important that the energy efficiency of existing buildings and optimizing its systems as a lower energy benefits both the environment and the economy. A building's ventilation system account for a large proportion of a property's energy use, and there is often great potential for the system to be optimized and streamlined. A property owner does not want properties that are vacant. Vacant premises mean less income in rent and in some cases there will be increased energy costs for the empty space in form of heating and ventilation, for the property owner to pay. Systems that can completely shut off or controlled depending on ventilation requirements needed for the latter cost will be reduced completely when the premises are vacant and that the total energy will decrease when a tenant moves out. Ventilating purpose is to divert moisture, heat, particulates and carbon dioxide so that a good indoor climate is created for the people staying in the building. The most common ventilation principle for public buildings is to vent air with a constant air flow through a CAV system. With demand-based ventilation in the form of a VAV system, huge savings can be made when one adjusts airflow to the actual ventilation requirement instead of ventilating the building with a constant maximum flow. An installation of a VAV system in the form of CO2 or presence control, reduces ventilation energy consumption, while the quality of the indoor environment is maintained. The work that has been carried out includes an energy survey of the property Brynäs 12:1 as an energy survey helps to understand a building's energy use, and identifies potential energy savings. The energy use for the building subsystems have been identified and analyzed in order to develop proposals for cost cutting measures. The results of the energy audit revealed that there was great potential for savings for ventilation units TA1, TA2 and TA3's electricity and heat use. If the measures for ventilation as presented in the work, such as flow and time reduction is taken, an energy saving of 333 MWh/year is achieved, which is 28% of the property's total annual energy consumption.
108

Wake survey behind a rotating ventilator

Rashid, Dewan Md. Harunur, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2002 (has links)
With environmental concern growing in both affluent and developing countries, roof top ventilators, a form of natural ventilation requiring only wind energy to ensure quality air circulation and comfort is becoming a considered choice of many households and industries. Unfortunately, however, many of these ventilators have evolved through trial and error and the flow physics associated with these ventilators is barely understood. The present experimental project was, therefore, undertaken as part of UNSW- Industry collaboration program funded under an Australian Research Council Grant to explore whether the aerodynamics forces acting on these ventilators during their operation could be obtained. A commercial roof top ventilator supplied by industry was, therefore, tested in an open jet wind tunnel of the University of New South Wales and the results are presented in this thesis. A novel feature of this project is the examination of the suitability of ???the three dimensional wake traverse??? technique to the wake of rotating ventilator. This technique has so far been applied with limited success to the wake of lifting bodies of fixed wing configuration only. In the absence of adequate data in the literature on rotating ventilator, the aerodynamics force components obtained by this technique have been compared against force balance measurements. The results show that the wake traverse technique is capable of determining lift and total drag forces associated with the ventilator flow during its operation from the pressure and velocity information gathered downstream of a ventilator in its wake. Generally, from these data, the technique also allows isolation of the profile and induced components of the drag force. However, from the induced drag value, while it is possible to determine the lift force, it is however, found that a more accurate value of lift force can be evaluated using axial vorticity formulation. The availability of the above technique which does not require measurements on the test specimen itself, will aid in providing a cost efficient investigation of the aerodynamic forces and consequently the performance of a roof top ventilator.
109

Advantages of using the ANSI/ASHRAE 110-1995 tracer gas test method vs. the ANSI/AIHA Z9.5-1992 face velocity test method for the chemical laboratory hood certification

Fahim, Mahdi. January 2006 (has links)
Thesis (M.S.)--University of Toledo, 2006. / "In partial fulfillment of the requirements for the degree of Master of Science in Occupational Health." Major advisor: Sheryl Milz. Includes abstract. Document formatted into pages: iv, 66 p. Title from title page of PDF document. Title at ETD Web site: Advantages of using the ANSI/ASHRAE 110-1995 tracer gas test method versus the ANSI/AIHA Z9.5-1992 face velocity test method for chemical laboratory hood certification. Bibliography: pages 58-61.
110

Estudo da eficiência para a ventilação natural dos sheds em hospitais da Rede Sarah / Study of the efficiency of natural ventilation of sheds Sarah network in Hospitals

Camargo, Renata Martinho de 19 August 2018 (has links)
Orientador: Lucila Chebel Labaki / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-19T06:39:40Z (GMT). No. of bitstreams: 1 Camargo_RenataMartinhode_M.pdf: 4984279 bytes, checksum: 362dc581c34f0a018e1778f146c62eab (MD5) Previous issue date: 2011 / Resumo: A ventilação natural em regiões tropicais é uma eficiente estratégia de projeto para a obtenção de conforto térmico e para a redução do consumo de energia. O aproveitamento dos recursos naturais e das condicionantes do clima melhora a integração do edifício com o entorno e a obtenção do conforto através de sistemas passivos de condicionamento. Os efeitos do vento em um edifício são analisados através da dinâmica dos fluidos computacional (CFD, Computational Fluid Dynamics) ou de estudos em túnel de vento. É importante quantificar variáveis como: velocidade, pressão, temperatura e coeficiente de pressão. Os Hospitais da Rede Sarah Kubistchek, projetados por João Filgueiras Lima, Lelé, são considerados bons exemplos de arquitetura bioclimática, devido as suas soluções passivas de conforto, como a utilização dos sheds, que promovem a iluminação e a ventilação natural. Esses hospitais foram construídos em várias capitais brasileiras, com diferentes climas. Este trabalho tem como objetivo avaliar a eficiência da ventilação natural dos Hospitais Sarah localizados nas cidades de Brasília e Belém. Essas cidades foram escolhidas devido às características climáticas bastante diferenciadas - clima quente seco e quente úmido. Os sheds no hospital de Belém funcionam como extratores de vento, ao passo que no hospital de Brasília Lago Norte foram projetados como captadores de vento. A análise é feita através de ensaios em túnel de vento de camada limite atmosférica. Os testes incluem medições de velocidade do ar e pressão em vários pontos dentro e fora dos edifícios. O hospital de Belém é analisado em sua implantação real e na situação em que o vento predominante incide perpendicularmente à fachada. Os resultados mostram que, tanto o conjunto de aberturas e o sistema de sheds do hospital de Belém, quanto a sua implantação, proporcionaram maior velocidade do ar nos ambientes internos do que o hospital Brasília Lago Norte. Os resultados dos coeficientes de pressão permitiram confirmar que, para os dois hospitais analisados, o projeto de ventilação natural aproveita as áreas de maior pressão para posicionamento das aberturas de entrada e saída de ar / Abstract: Natural ventilation in tropical regions is an efficient design strategy for achieving thermal comfort and reducing energy consumption. The utilization of natural resources and climate conditions improves integration of the building with its surroundings and allows comfort conditions through passive systems of conditioning. The effects of wind on a building are analyzed using computational fluid dynamics (CFD, Computational Fluid Dynamics) or wind tunnel studies. It is important to quantify variables such as speed, pressure, temperature and pressure coefficient. The Sarah Kubitschek Network hospital, designed by João Filgueiras Lima, Lelé, are considered good examples of bioclimatic architecture, due to the passive solutions for comfort, such as the use of sheds, which provide natural lighting and ventilation. These hospitals were built in several Brazilian cities with different climates. This study aims to evaluate the efficiency of natural ventilation of Sarah hospitals located in the cities of Brasília and Belém. These cities were chosen because of the different climate characteristics of the two cities - mild dry and hot humid. The sheds in the hospital of Belem act as wind extractors, while those in in Brasilia Lago Norte hospital was designed as a means of wind catchers. The analysis is done through testing in atmospheric boundary layer wind tunnel. The tests include measurements of air velocity and pressure at several points inside and outside of buildings. The Belém hospital is analyzed in its actual implantation and in the situation where the prevailing incident wind is perpendicular to the facade. The results show that both the number of openings and the shed system in the hospital in Belém, as well as its implantation, provided a higher air speed in indoor environments than the hospital Brasília Lago Norte. The results for the pressure coefficients allow to confirm that for both hospitals studied, the design of natural ventilation takes advantage of the higher pressure areas for positioning of the income and exit of air / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil

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