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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.
1

Modelling of energy requirements by a narrow tillage tool

Ashrafi Zadeh, Seyed Reza 04 July 2006
The amount of energy consumed during a tillage operation depends on three categories of parameters: (1) soil parameters (2) tool parameters and (3) operating parameters. Although many research works have been reported on the effects of those parameters on tillage energy, the exact number of affecting parameters and the contribution of each parameter in total energy requirement have not been specified. A study with the objectives of specifying energy consuming components and determining the amount of each component for a vertical narrow tool, particularly at high speeds of operation, was conducted in the soil bin facilities of the Department of Agricultural and Bioresource Engineering, University of Saskatchewan. <p>Based on studies by Blumel (1986) and Kushwaha and Linke (1996), four main energy consuming components were assumed: <p>(1) energy requirements associated with soil-tool interactions;<p>(2) energy requirements associated with interactions between tilled and fixed soil masses;<p>(3) energy requirements associated with soil deformation; and <p>(4) energy requirements associated with the acceleration of the tilled soil. <p> Energy requirement of a vertical narrow tool was calculated based on the draft requirement of the tool measured in the soil bin. The effects of three variables, moisture content, operating depth and forward speed, were studied at different levels: (1) moisture content at 14% and 20%; (2) depth at 40, 80, 120 and 160 mm; and (3) speed at 1, 8, 16 and 24 km h-1. Total energy requirement was divided into these four components based upon the procedure developed in the research. <p>Regression equations for different energy components were developed based on experimental data of two replicates and then validated by extra soil bin experiments conducted at same soil and tool but different operational conditions. The set up of energy components data in the model development showed good correlation with the available experimental data for all four components. Coefficients of all regression equations showed a first order energy-moisture content relationship best applicable to those equations of energy components. For the acceleration component, energy-depth relationship at all speed levels resulted in an equation which included first and second orders of depth. In contrast, if only two higher levels of speed were used in the regression model, the relationship between acceleration energy and depth resulted in the second order of depth. When experimental data of acceleration energy at 8, 16, and 24 km h-1 speeds were used in the regression equation, the acceleration energy-speed relationship resulted in both linear and quadratic relationships. It was concluded that for the tool and soil conditions used in the experiments, 8 km h-1 speed resulted in only linear relationship. On the other hand, 16 and 24 km h-1 speeds resulted in a quadratic relationship. Therefore, for all 3 speeds used in experiments, both linear and quadratic relationships were obtained. Considering that the tool was operating at high speeds, this research is expected to contribute valuable experimental data to the researchers working in the field of soil dynamics.
2

Modelling of energy requirements by a narrow tillage tool

Ashrafi Zadeh, Seyed Reza 04 July 2006 (has links)
The amount of energy consumed during a tillage operation depends on three categories of parameters: (1) soil parameters (2) tool parameters and (3) operating parameters. Although many research works have been reported on the effects of those parameters on tillage energy, the exact number of affecting parameters and the contribution of each parameter in total energy requirement have not been specified. A study with the objectives of specifying energy consuming components and determining the amount of each component for a vertical narrow tool, particularly at high speeds of operation, was conducted in the soil bin facilities of the Department of Agricultural and Bioresource Engineering, University of Saskatchewan. <p>Based on studies by Blumel (1986) and Kushwaha and Linke (1996), four main energy consuming components were assumed: <p>(1) energy requirements associated with soil-tool interactions;<p>(2) energy requirements associated with interactions between tilled and fixed soil masses;<p>(3) energy requirements associated with soil deformation; and <p>(4) energy requirements associated with the acceleration of the tilled soil. <p> Energy requirement of a vertical narrow tool was calculated based on the draft requirement of the tool measured in the soil bin. The effects of three variables, moisture content, operating depth and forward speed, were studied at different levels: (1) moisture content at 14% and 20%; (2) depth at 40, 80, 120 and 160 mm; and (3) speed at 1, 8, 16 and 24 km h-1. Total energy requirement was divided into these four components based upon the procedure developed in the research. <p>Regression equations for different energy components were developed based on experimental data of two replicates and then validated by extra soil bin experiments conducted at same soil and tool but different operational conditions. The set up of energy components data in the model development showed good correlation with the available experimental data for all four components. Coefficients of all regression equations showed a first order energy-moisture content relationship best applicable to those equations of energy components. For the acceleration component, energy-depth relationship at all speed levels resulted in an equation which included first and second orders of depth. In contrast, if only two higher levels of speed were used in the regression model, the relationship between acceleration energy and depth resulted in the second order of depth. When experimental data of acceleration energy at 8, 16, and 24 km h-1 speeds were used in the regression equation, the acceleration energy-speed relationship resulted in both linear and quadratic relationships. It was concluded that for the tool and soil conditions used in the experiments, 8 km h-1 speed resulted in only linear relationship. On the other hand, 16 and 24 km h-1 speeds resulted in a quadratic relationship. Therefore, for all 3 speeds used in experiments, both linear and quadratic relationships were obtained. Considering that the tool was operating at high speeds, this research is expected to contribute valuable experimental data to the researchers working in the field of soil dynamics.
3

Developing a procedure to measure grinding energy of forages as a predictor of forage fragility

Prinsloo, Elfriede January 2014 (has links)
The structural organization of plant organs and tissues determine the intake potential through the ease of forage particle breakdown, the nature of the particles produced as well as the rate of passage from the rumen. The cell wall content of forages influences the amount of energy required for chewing, and accounts for a considerable proportion of the total energy requirement. In the past, neutral detergent fibre (NDF) has been used as the only feed characteristic to predict the filling effects of forages, but there is substantial evidence that NDF alone is inadequate to make these predictions. Forage fragility is defined as the relative rate at which the particle size of forages are reduced during processes such as chewing or milling, and forage fragility might be related to lignin concentration and digestibility, as well as to anatomical differences among plant species. The physical characteristics of feedstuffs are not measured regularly, and these physical characteristics in relation to their nutritional properties should be taken into account for more precise feed formulation. Through the measurement of grinding energy, the possibility exists to predict forage fragility as related to the chemical composition of forages, which could lead to improved predictions of animal chewing activity and energy usage during the process of chewing. In order to investigate the possibility of developing a model for the prediction of forage fragility, twenty eight different forage samples were collected from 11 different locations. Samples included legumes, C3- and C4- grasses. Dried samples were analysed for various chemical components, as well as 24-hour in vitro NDF digestibility (ivNDFd) and rate of NDF degradation (NDFkd). Dried samples were pre-cut with a knife mill, fitted with a 2 cm screen, after which particle size distribution for each sample was determined using a Retsch Sieve shaker. Ten g duplicate samples were milled with a laboratory hammer mill and an ultra-centrifugal mill, both fitted with a 1 mm screen, for the measurement of grinding energy. During the grinding process, energy usage of the specific mill was measured using a data logger with corresponding computer software and energy transducer. Energy measurements were reported as J/g sample on dry matter (DM) basis. The 2 cm samples were milled with the knife mill again, fitted with a 1 mm screen, after which particle size distribution was determined again to analyse change in particle distribution for each forage sample. The results of this study indicated that dry matter, nitrogen, ivNDFd, NDFkd and initial particle size (IPS) can all be associated with increased forage fragility, as there was a decrease in energy usage during grinding with an increase in any of the aforementioned components. The acid detergent fibre (ADF), NDF, total phenols (TP), non-tannic phenols (NTP), as well as the % change in particle size can all be associated with decreased forage fragility, as there was an increase in energy usage during grinding with an increase in any one of these components. It would be expected that acid detergent lignin (ADL) is also associated with decreased forage fragility; however, this can only be assumed as the results for the effect of lignin on forage fragility are inconclusive in this study. Literature on energy requirement for milling operations of forages is inadequate. Grinding energy is related to the stem mechanical properties (such as maximum cutting force and stem shear strength), and physical properties (such as stem diameter, DM density and moisture content). The use of grinding energy has the potential be a practical and useful measure to predict forage fragility, however, the relative contribution of factors such as original particle size, shape, surface area, morphology and many other factors toward the fragility of forages is difficult to predict. More research is needed on the prediction of forage fragility before it can be incorporated as a meaningful input into nutritional models such as NRC, CNCPS and AMTS. / Dissertation (MScAgric)--University of Pretoria, 2014. / tm2015 / Animal and Wildlife Sciences / MScAgric / Unrestricted
4

Partição da energia metabolizável para codornas japonesas na fase de produção de ovos / Partition of metabolizable energy for japanese quails in the egg production phase

Nóbrega, Ingryd Palloma Teodósio da 23 February 2018 (has links)
Submitted by Ingryd Palloma Teodósio da Nóbrega (palloma_nobrega@hotmail.com) on 2018-04-19T12:42:22Z No. of bitstreams: 1 Dissertação de Mestrado_definitivo.pdf: 1192753 bytes, checksum: 780733e53b843a769b459dd932674e60 (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-04-19T12:57:20Z (GMT) No. of bitstreams: 1 nobrega_ipt_me_jabo.pdf: 1192753 bytes, checksum: 780733e53b843a769b459dd932674e60 (MD5) / Made available in DSpace on 2018-04-19T12:57:20Z (GMT). No. of bitstreams: 1 nobrega_ipt_me_jabo.pdf: 1192753 bytes, checksum: 780733e53b843a769b459dd932674e60 (MD5) Previous issue date: 2018-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Compreender o metabolismo energético das aves e como a energia é utilizada para mantença, ganho de peso e produção de ovos, permite a elaboração e avaliação de modelos que estimam a exigência nutricional considerando as diferenças de peso corporal (P), ganho de peso (GP) e massa de ovo (MO) na avicultura industrial. Objetivou-se com esta pesquisa analisar os coeficientes que representam a partição da energia ingerida por codornas japonesas na fase de produção de ovos, a partir de um estudo dose-resposta. Foram utilizadas 70 codornas japonesas da linhagem VICAMI®, com 24 semanas de idade, durante 8 semanas, alojadas em galpão convencional. Duas dietas foram formuladas, uma com alto (3.600 kcal/kg) e a outra com baixo (2.100 kcal/kg) teor de energia. Para modificar a energia retida pelas aves, foi empregada a técnica da diluição, obtendo os níveis crescente de energia metabolizável da dieta. Foram utilizados sete tratamentos distribuídos inteiramente ao acaso, com dez repetições e uma codorna por unidade experimental. Os tratamentos foram 2.118; 2.381; 2.557; 2.776; 2.908; 3.171 e 3.435 kcal/kg, com base na composição analisada das dietas determinadas em ensaio de metabolismo. As variáveis analisadas foram ingestão de energia metabolizável (IEM), produção de calor (PC) e energia retida (ER) expressas em kcal/kg0,67. A energia metabolizável para mantença (EMm) foi obtida a partir da relação entre ER e IEM, considerando a condição ER = 0. A exigência metabolizável para ganho de peso (EMg) foi estimada pela relação entre eficiência de utilização de energia (k) e energia líquida para ganho (ELg). A exigência de energia metabolizável para massa de ovo (EMo), foi obtida por meio da energia retida no ovo, dividida pela eficiência de utilização de energia para massa de ovo (ko). Os valores estimados para EMm, EMg e EMo foram 155,60 kcal/kg P0,67; 5,89 kcal/g e 2,74 kcal/g, respectivamente. Os modelos que predizem a IEM baseados nos parâmetros que representam exigência de energia de acordo com seu fracionamento, foram avaliados por meio da decomposição linear do erro (observado - predito), em erro escalar e viés de predição, obtidos por regressão linear entre os erros e valores preditos. O modelo obtido foi IEM = 155,60 × P0,67 + 5,89 × GP + 2,74 × MO, a composição do erro analisado (3,79 kcal/ave.dia) mostrou que o modelo é imparcial, com 93% de precisão nas estimativas, portanto, capaz de predizer o conjunto de dados analisados, o que valida seu uso. / – To understand the energy metabolism of birds and how energy is used for maintenance, weight gain and egg production, allow the elaboration and evaluation of models that estimate the nutritional requirement considering the differences of body weight (BW), body weight gain (BWG) and egg mass (EO) in industrial poultry. The objective of this research was to analyze the coefficients that represent the partition of the energy ingested by Japanese quails in the egg production phase, from a doseresponse study. In a conventional shed it was housed 70 Japanese quails of VICAMI® line, at 24 weeks old, during 8 weeks. Based on the dilution technique it was formulated two energy levels diets, one with high (3,600 kcal/kg) and other with low (2,100 kcal/kg). Seven treatments were randomly distributed, with ten replicates and one quail per experimental unit. Treatments were levels of metabolizable energy in the diet being: 2,118; 2,381; 2,557; 2,776; 2,908; 3,171 and 3,435 kcal/kg. The variables analyzed were metabolizable energy intake (MEI), heat production (HP) and retained energy (RE) expressed in kcal/kg0.67. The metabolizable energy for maintenance (MEm) was obtained from the relation between RE and MEI, solving the equation RE = 0. The metabolizable requirement for weight gain (MEg) was estimated by the relation between use efficiency of energy (k) and net energy for gain (NEg). The metabolizable energy requirement for egg mass (MEe) was obtained by the relation between energy retained in the egg, divided by the energy utilization efficiency for egg mass (ke). The estimated values for MEm, MEg, MEe were 155.60 kcal/kg BW0.67 , 5.89 kcal/g and 2.74 kcal/g; respectively. The models that predict MEI based on the parameters that represent the energy requirement according to its fractionation were evaluated by linear error decomposition (observed - predicted), in scalar error and prediction bias obtained by linear regression between errors and predicted values. The obtained model was MEI = 155.60 × BW0.67 + 5.89 × BWG + 2.74 × EO, the analyzed error composition (3.79 kcal/bird.day), of display showing the model is unbiased, with 93% accuracy in the estimates, therefore, able to predict the analyzed data set, which validates its use.
5

Captage du CO2 en post combustion par procédé de perméation gazeuse / Gas permeation process for post combustion CO2 capture

Pfister, Marc 05 April 2017 (has links)
La technologie de Captage et Stockage du CO2 (CSC) est considérée comme une des principales solutions pour limiter les rejets de gaz à effet de serre (CO2) et lutter contre le réchauffement climatique. L’étape de captage fait appel à un procédé de séparation des fumées de post combustion qui a pour fonction l’extraction sélective du CO2 des autres composés. Les principales performances visées sont un taux de capture et une pureté du CO2 supérieurs à 90%, ainsi qu’une consommation énergétique minimale afin de ne pas générer un niveau trop élevé d’émissions secondaires de CO2. La perméation gazeuse par membrane dense est une technologie de séparation potentiellement applicable au captage du CO2 en post combustion. Sur la base de différents types de matériaux et mécanisme de transport associés (processus physique ou chimique) une large plage de valeurs de perméabilité et de sélectivité peut être atteinte. Une des dernières familles de membrane ayant démontrée des performances de séparation pouvant être intéressantes pour le captage du CO2 sont les membranes à transport facilité dites ‘’réactives ‘’. Une analyse systématique des performances de séparation de modules membranaires basés sur des membranes physiques (polymères denses) et sur des membranes réactives (transport facilité) pour le traitement de fumées de post combustion a été réalisée. La simulation d’un procédé de captage complet, incluant un ou deux étages de séparation membranaire, une étape de séchage et une étape de compression a ensuite été effectuée. L’ensemble des résultats, en particulier la pénalité énergétique globale du système et l’estimation des surfaces membranaires nécessaires, permet de positionner la technologie de perméation gazeuse comparativement aux autres procédés de captage / CO2 Capture and Storage (CCS) is a promising solution to separate CO2 from flue gas, to reduce the CO2 emissions in the atmosphere, and hence to reduce global warming. In CCS, one important constraint is the high additional energy requirement of the different capture processes. That statement is partly explained by the low CO2 fraction in the inlet flue gas and the high output targets in terms of CO2 capture and purity (>90%).Gas permeation across dense membrane can be used in post combustion CO2 capture. Gas permeation in a dense membrane is ruled by a mass transfer mechanism and separation performance in a dense membrane are characterized by component’s effective permeability and selectivity. One of the newest and encouraging type of membrane in terms of separation performance is the facilitated transport membrane. Each particular type of membrane is defined by a specific mass transfer law. The most important difference to the mass transfer behavior in a dense membrane is related to the facilitated transport mechanism and the solution diffusion mechanism and its restrictions and limitations.Permeation flux modelling across a dense membrane is required to perform a post combustion CO2 capture process simulation. A CO2 gas permeation separation process is composed of a two-steps membrane process, one drying step and a compression unit. Simulation on the energy requirement and surface area of the different membrane modules in the global system are useful to determine the benefits of using dense membranes in a post combustion CO2 capture technology
6

Terapia nutricional em politraumatizados sob ventilação mecânica: estudo comparativo entre prescrição e oferta calórica

Couto, Cecília Flávia Lopes January 2011 (has links)
Introdução: No período de hipermetabolismo em que se encontra o paciente politraumatizado, é necessário que a administração calórica seja adequada e suficiente para suprir o intenso gasto energético do organismo. Com suporte nutricional inadequado, as reservas de aminoácidos dos músculos esqueléticos e respiratórios são exigidas, expondo o paciente crítico ao risco nutricional e suas consequências. Objetivos: Quantificar o aporte calórico administrado a pacientes em ventilação mecânica (VM), analisar a adequação da prescrição e correlacionar as calorias ofertadas com o tempo em VM. Métodos: Estudo de coorte prospectivo observacional conduzido na Unidade de Terapia Intensiva de um hospital público de Porto Alegre (RS) no período de abril de 2008 a julho de 2009. Foram estudados 60 pacientes politraumatizados em Nutrição Enteral e VM e internados por mais de 5 dias na UTI. Foram verificados o tempo de permanência em VM e a oferta calórica durante o período que permaneceram em terapia nutricional enteral. Resultados: A média do percentual de calorias administradas foi de 68,6% (±12,3) do prescrito. Nove pacientes (15,0%) receberam menos da metade do que deveriam, apenas 16 (26,7%) receberam no mínimo 80,0%. Apenas 25,0% dos pacientes receberam prescrição calórica adequadamente (entre 90% e 110%). Não houve associação significativa entre o Valor Energético Total administrado e o tempo de VM (rs=0,130; p=0,321), tempo de UTI (rs=-0,117; p=0,372) e tempo de internação hospitalar (rs=-0,152; p=0,246). Conclusão: Neste estudo foi verificado que maioria dos pacientes politraumatizados em ventilação mecânica não recebeu um aporte energético adequado, ficando assim expostos aos riscos da desnutrição e seus desfavoráveis desfechos clínicos. / Introduction: During the period of hypermetabolism faced by multiple trauma patients, their calorie intake has to be appropriate and sufficient to meet their high energy expenditure. When there is not appropriate nutritional care, the amino acids from the skeletal and respiratory muscles are used; thus critical patients are exposed to nutritional risk and its consequences. Objectives: To quantify the calories provided to patients on mechanical ventilation (MV); to analyze the appropriateness of the prescription; and to correlate the calories offered with the period of time on MV. Methods: Prospective observational cohort study conducted at the intensive care unit (ICU) of a public hospital in Porto Alegre (RS), Brazil, from April 2008 to July 2009. We studied 60 multiple trauma patients on MV receiving enteral nutrition who remained longer than 5 days at the ICU. We investigated the length of time patients were on MV and their calorie intake while receiving enteral nutrition. Results: The mean percentage of calories was 68.6% (±12.3) of the amount prescribed. Nine patients (15.0%) received less than half of the prescription. Only 16 (26.7%) patients received at least 80.0%. Only 25.0% of patients received the amount of calories according to the prescription (between 90% and 110%). There was no significant association between total energy value and the period of time on MV (rs = 0.130, p = 0.321), length of ICU stay (rs = -0.117, p = 0.372), and length of hospital stay (rs = -0.152, p = 0.246). Conclusion: We found that most multiple trauma patients on MV did not receive an adequate energy intake; therefore, they were exposed to the risks of malnutrition and its adverse clinical outcomes.
7

Terapia nutricional em politraumatizados sob ventilação mecânica: estudo comparativo entre prescrição e oferta calórica

Couto, Cecília Flávia Lopes January 2011 (has links)
Introdução: No período de hipermetabolismo em que se encontra o paciente politraumatizado, é necessário que a administração calórica seja adequada e suficiente para suprir o intenso gasto energético do organismo. Com suporte nutricional inadequado, as reservas de aminoácidos dos músculos esqueléticos e respiratórios são exigidas, expondo o paciente crítico ao risco nutricional e suas consequências. Objetivos: Quantificar o aporte calórico administrado a pacientes em ventilação mecânica (VM), analisar a adequação da prescrição e correlacionar as calorias ofertadas com o tempo em VM. Métodos: Estudo de coorte prospectivo observacional conduzido na Unidade de Terapia Intensiva de um hospital público de Porto Alegre (RS) no período de abril de 2008 a julho de 2009. Foram estudados 60 pacientes politraumatizados em Nutrição Enteral e VM e internados por mais de 5 dias na UTI. Foram verificados o tempo de permanência em VM e a oferta calórica durante o período que permaneceram em terapia nutricional enteral. Resultados: A média do percentual de calorias administradas foi de 68,6% (±12,3) do prescrito. Nove pacientes (15,0%) receberam menos da metade do que deveriam, apenas 16 (26,7%) receberam no mínimo 80,0%. Apenas 25,0% dos pacientes receberam prescrição calórica adequadamente (entre 90% e 110%). Não houve associação significativa entre o Valor Energético Total administrado e o tempo de VM (rs=0,130; p=0,321), tempo de UTI (rs=-0,117; p=0,372) e tempo de internação hospitalar (rs=-0,152; p=0,246). Conclusão: Neste estudo foi verificado que maioria dos pacientes politraumatizados em ventilação mecânica não recebeu um aporte energético adequado, ficando assim expostos aos riscos da desnutrição e seus desfavoráveis desfechos clínicos. / Introduction: During the period of hypermetabolism faced by multiple trauma patients, their calorie intake has to be appropriate and sufficient to meet their high energy expenditure. When there is not appropriate nutritional care, the amino acids from the skeletal and respiratory muscles are used; thus critical patients are exposed to nutritional risk and its consequences. Objectives: To quantify the calories provided to patients on mechanical ventilation (MV); to analyze the appropriateness of the prescription; and to correlate the calories offered with the period of time on MV. Methods: Prospective observational cohort study conducted at the intensive care unit (ICU) of a public hospital in Porto Alegre (RS), Brazil, from April 2008 to July 2009. We studied 60 multiple trauma patients on MV receiving enteral nutrition who remained longer than 5 days at the ICU. We investigated the length of time patients were on MV and their calorie intake while receiving enteral nutrition. Results: The mean percentage of calories was 68.6% (±12.3) of the amount prescribed. Nine patients (15.0%) received less than half of the prescription. Only 16 (26.7%) patients received at least 80.0%. Only 25.0% of patients received the amount of calories according to the prescription (between 90% and 110%). There was no significant association between total energy value and the period of time on MV (rs = 0.130, p = 0.321), length of ICU stay (rs = -0.117, p = 0.372), and length of hospital stay (rs = -0.152, p = 0.246). Conclusion: We found that most multiple trauma patients on MV did not receive an adequate energy intake; therefore, they were exposed to the risks of malnutrition and its adverse clinical outcomes.
8

Terapia nutricional em politraumatizados sob ventilação mecânica: estudo comparativo entre prescrição e oferta calórica

Couto, Cecília Flávia Lopes January 2011 (has links)
Introdução: No período de hipermetabolismo em que se encontra o paciente politraumatizado, é necessário que a administração calórica seja adequada e suficiente para suprir o intenso gasto energético do organismo. Com suporte nutricional inadequado, as reservas de aminoácidos dos músculos esqueléticos e respiratórios são exigidas, expondo o paciente crítico ao risco nutricional e suas consequências. Objetivos: Quantificar o aporte calórico administrado a pacientes em ventilação mecânica (VM), analisar a adequação da prescrição e correlacionar as calorias ofertadas com o tempo em VM. Métodos: Estudo de coorte prospectivo observacional conduzido na Unidade de Terapia Intensiva de um hospital público de Porto Alegre (RS) no período de abril de 2008 a julho de 2009. Foram estudados 60 pacientes politraumatizados em Nutrição Enteral e VM e internados por mais de 5 dias na UTI. Foram verificados o tempo de permanência em VM e a oferta calórica durante o período que permaneceram em terapia nutricional enteral. Resultados: A média do percentual de calorias administradas foi de 68,6% (±12,3) do prescrito. Nove pacientes (15,0%) receberam menos da metade do que deveriam, apenas 16 (26,7%) receberam no mínimo 80,0%. Apenas 25,0% dos pacientes receberam prescrição calórica adequadamente (entre 90% e 110%). Não houve associação significativa entre o Valor Energético Total administrado e o tempo de VM (rs=0,130; p=0,321), tempo de UTI (rs=-0,117; p=0,372) e tempo de internação hospitalar (rs=-0,152; p=0,246). Conclusão: Neste estudo foi verificado que maioria dos pacientes politraumatizados em ventilação mecânica não recebeu um aporte energético adequado, ficando assim expostos aos riscos da desnutrição e seus desfavoráveis desfechos clínicos. / Introduction: During the period of hypermetabolism faced by multiple trauma patients, their calorie intake has to be appropriate and sufficient to meet their high energy expenditure. When there is not appropriate nutritional care, the amino acids from the skeletal and respiratory muscles are used; thus critical patients are exposed to nutritional risk and its consequences. Objectives: To quantify the calories provided to patients on mechanical ventilation (MV); to analyze the appropriateness of the prescription; and to correlate the calories offered with the period of time on MV. Methods: Prospective observational cohort study conducted at the intensive care unit (ICU) of a public hospital in Porto Alegre (RS), Brazil, from April 2008 to July 2009. We studied 60 multiple trauma patients on MV receiving enteral nutrition who remained longer than 5 days at the ICU. We investigated the length of time patients were on MV and their calorie intake while receiving enteral nutrition. Results: The mean percentage of calories was 68.6% (±12.3) of the amount prescribed. Nine patients (15.0%) received less than half of the prescription. Only 16 (26.7%) patients received at least 80.0%. Only 25.0% of patients received the amount of calories according to the prescription (between 90% and 110%). There was no significant association between total energy value and the period of time on MV (rs = 0.130, p = 0.321), length of ICU stay (rs = -0.117, p = 0.372), and length of hospital stay (rs = -0.152, p = 0.246). Conclusion: We found that most multiple trauma patients on MV did not receive an adequate energy intake; therefore, they were exposed to the risks of malnutrition and its adverse clinical outcomes.
9

Hodnocení energetické náročnosti budov národním kalkulačním nástrojem NKN II a porovnání s výsledky energetické simulace / Evaluation of energy demands of buildings using NKN II and comparison with results of energy simulation

Hlubinka, Jakub January 2016 (has links)
The Master Thesis evaluates the energy demands of two types of family houses. The calculations are performed using the national calculation tool NKN II and the simulation software TRNSYS. The results of both methods are compared and their differences explained. Both calculation tools are compared from the user point view and finally their applicability for project designers is evaluated.
10

Méthodologie de dimensionnement sur cycle de vie d’une distribution en courant continu dans le bâtiment : applications aux câbles et convertisseurs statiques DC/DC / Sizing methodology on the entire life cycle for building DC distribution : application on wiring and DC/DC converters

Jaouen, Cédric 09 July 2012 (has links)
Avec l’apparition des systèmes PV en toiture et des véhicules électriques, le nouveau contexte énergétique au sein du bâtiment pose, sous un nouvel angle, la question de la distribution en courant continu au sein des bâtiments. Mais comment évaluer objectivement l’intérêt d’un réseau DC ? Dans un contexte où l’énergie et les impacts environnementaux prennent chaque jour plus d’importance, la quantification des performances d’un tel système selon sa seule phase d’usage ne répond pas complètement à la question son impact global. C’est pourquoi nous proposons d’aborder la question via l’éco-dimensionnement des composants constituant ce système. Pour simplifier un problème fondamentalement complexe (multi-critères), nous avons choisi d’effectuer ces dimensionnements sur la base de la minimisation de leur consommation d’énergie primaire sur l’ensemble de leur cycle de vie (pertes + énergie grise = Gross Energy Requirement GER). L’un des objectifs étant d’apporter à la fois une méthodologie mais aussi les premiers éléments qui permettront de déterminer un optimum du niveau de tension d’une distribution en courant continu dans les bâtiments. / Since the development of roof PV systems and electric vehicles, the use of DC distribution for building has to be explored. However, an objective criterion has to be used to evaluate the interest of such distribution. While energy consumption and environmental impact criteria gain in importance, the performance quantification of such system over the use phase is not sufficient to illustrate its whole impact. That’s why we propose to tackle this evaluation through the eco-sizing of distribution component. In order to simplify this complex problem, based on a multi-criterion approach, we propose to size the components based on the minimization of their primary energy consumption over their entire life cycle. The resulting Gross Energy Requirement GER includes the embodied energy and the losses during the use phase. The objectives are to propose a methodology to determine the optimal voltage level for the building DC distribution, and also to illustrate the proposed approach from case studies. This methodology is applied on wiring and DC/DC converters.

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