<p>På grund av världens växande befolkning och urbaniseringen blir problem relaterade till fenomenet urbana värmeöar mer och mer påtagliga. Eftersom urbana parker kan minska påfrestningen skapad av urbana värmeöar kan de vara ett kraftfullt verktyg vid klimatdesign i städer. Temperaturen nära en yta bestäms av energiutbytet mellan ytan och luften ovanför och det är därför nödvändigt att man förstår energibalansen vid markytan för att kunna hantera parkernas mikroklimat. Syftet med det här arbetet var att studera skillnaderna mellan energibalansen för olika ytor i parken och i dess omgivning och att relatera skillnaderna i energibalanserna till temperaturskillnaderna.</p><p>Mätningarna utfördes under tre klara sommardagar i parken Humlegården i centrala Stockholm. Mätutrustningen var monterad på en kärra som flyttades från mätplats till mätplats. Mätplatserna representerade olika typiska ytor i Humlegården och i dess omgivning: en skuggad och en öppen gräsmatta, en öppen och en skuggad grusyta och två asfaltytor, varav en löper i nord-sydlig riktning och en i öst-västlig riktning.</p><p>Energiflödena beräknades med hjälp av data för luft- och yttemperatur, vindhastighet, luftfuktighet och nettostrålning.</p><p>Resultaten visade att den tydligaste skillnaden mellan gräs- och grusytorna i parken var att gräsytorna hade ett större nedåtriktat latent värmeflöde under natten och ett mindre markvärmeflöde under hela dygnet. Den mest distinkta skillnaden mellan de skuggade och öppna ytorna i parken var att de skuggade ytorna hade mindre energiflöden under dagen och att de till skillnad från de andra ytorna hade ett nedåtriktat sensibelt värmeflöde under dagen. Den största skillnaden mellan ytorna i och utanför parken var att asfaltytorna hade ett större uppåtriktat sensibelt värmeflöde och markvärmeflöde under natten.</p><p>Under natten var den svalaste mätplasten den öppna gräsmattan, vilken också var den enda mätplasten med ett nedåtriktat sensibelt värmeflöde under natten. Jämfört med de andra ickeskuggade mätplasterna hade den öppna gräsmattan ett mindre markvärmeflöde. Varmaste mätplasterna under natten var asfaltytorna som även hade ett större uppåtriktat sensibelt och markvärmeflöde än de andra ytorna. Under dagen var de skuggade ytorna i parken de svalaste platserna. De var de enda ytorna med ett nedåtriktat sensibelt värmeflöde och nettostrålningen vid ytan var mindre än för de flesta andra mätplatser.</p> / <p>The world’s growing population and the increasing urbanization has made problems related to the urban heat island phenomenon to become more pronounced and since urban parks reduce the stress produced by the urban heat island they can be powerful tools in urban climate design. The temperature near the surface in a park is determined by the energy exchanges between the surface and the air above and it is therefore necessary to understand the surface energy balance of parks to intelligently manage their thermal microclimate. The objectives of this work were to study how the energy balances differ between different surfaces inside parks and in their built-up surroundings and to relate the surface energy balances to temperature differences.</p><p>Measurements were conducted during three clear summer days in the park Humlegården located in central Stockholm. The measuring instruments were mounted on a cart, which was transported from observation site to observation site. The observation sites represented typical surfaces found in an urban park and its surroundings: one shaded and one open grass surface, one open and one shaded gravel surface and two paved surfaces representing streets running in the north-south and east-west directions respectively. The energy fluxes were calculated using air and surface temperatures, wind speed, air humidity and net radiation data.</p><p>The most pronounced differences between the shaded and open surfaces in the park was that the shaded surfaces in general had smaller energy fluxes during daytime and that they had a downward directed sensible heat flux while the open surfaces had an upward directed sensible heat flux during the day. The most significant difference between the grass and the gravel surfaces in the park was that the grass surfaces had a bigger downward directed latent heat flux during the night and a smaller ground heat flux during both day and night. The largest differences between the surfaces inside the park and those in its built-up vicinities were that the paved surfaces had a larger upward directed sensible and ground heat flux during the night than the other surfaces. During the day the north-south directed paved site had a downward directed ground heat flux that was much larger than the ground heat flux for the other sites.</p><p>The coolest site during the night was the non-shaded grass surface, which was the only site with a downward directed sensible heat flux during the night. Compared to the other nonshaded sites the open grass surface had a much smaller ground heat flux. Warmest sites during the night were the paved surfaces, which had a larger upward directed sensible and ground heat flux than the other surfaces. At the built-up sites the walls also contributed with sensible heat flux, i.e. the total sensible heat flux in the built-up area was larger than what comes from the street surface only. During the day the shaded surfaces in the park were the coolest sites. The shaded surfaces had less net radiation compared to the other non-shaded surfaces and were the only sites that had a downward directed sensible heat flux.</p>

The first part of this thesis examines and compares the separate closure formalisms of Wyld and Martin, Siggia, and Rose (MSR). The simplicity of Wyld’s perturbation scheme is offset by an incorrect renormalisation, this contrasts with the formally exact analysis of MSR. The work here shows that a slight change in Wyld’s renormalisation keeps the main results intact and, in doing so, demonstrates that this formalism is equivalent to MSR. The remainder of the thesis is concerned with turbulent dissipation. A numerical solution of the Local Energy Transfer theory, or LET, is reworked and extended to compute decaying and forced turbulence at large Reynolds numbers. Using this numerical simulation, the phenomenon of turbulent dissipation is investigated. In order to use decaying turbulence to study the turbulent dissipation rate as a function of Reynolds number, it is necessary to choose an appropriate time with which a measurement can be taken. Using phenomenological arguments of the evolution of a turbulent fluid, criteria for establishing such a time are developed. An important study in turbulence is the dissipation rate in the limit of vanishing viscosity, also known as the dissipation anomaly. This thesis derives an equation for the dissipation rate from the spectral energy balance equation. Using the LET computation for both decaying and forced turbulence, results are obtained that can be used along with the equation to study the mechanisms behind the dissipation anomaly. It is found that there is a difference in the behaviour of the normalised dissipation rate between decaying and forced turbulence and, for both cases, it is largely controlled by the energy flux.

This project investigates the near surface energy balance on the Murt`el-Corvatsch rock glacier in the Upper Engadine, Swiss Alps, using the 1D physical SNOWPACK model. A correct representation of the near surface energy balance is important to predict the long term evolution of permafrost below rock glaciers. This is of interest in the context of future water availability and management of water resources in a changing climate and also in the context of natural hazards. Some difficulties in modelling the thermal regime of rock glaciers are related to the large pore spaces between the blocks, which allow for different modes of heat transport. With this in mind, different modelling approaches were investigated: using the standard SNOWPACK (without advective heat flux, ventilation or canopy module), adding an advective heat flux, using the ventilation and canopy modules. The most promising results, i.e. the best match between measured and modelled temperatures, were obtained from the ventilation parameterisation. This parameterisation accounts for boundary-layer air penetrating into the blocky layer. Furthermore it was found that the most important input variables are the thickness of the the blocky layer, since this is where the additional modes of heat exchange take place, and the ice and void volume fraction together with the field capacity in the icy layer. The latter are particularly relevant for long term modelling as they determine the amount of ice melt and water transport in the icy layer. Measured and modelled temperatures at depths of 0.5 m, 2.5 m, 3.5 m and 7.5 m were compared. Generally good agreements between modelled and measured temperatures were obtained for the depths 0.5 m, 3.5 m and 7.5 m. The slight warming trend at the end of the modelled period (2012- 2016) that can be observed in the borehole data is also present in the modelled temperatures. The depth of 2.5 m shows the least agreement between modelled and measured temperatures with and overestimation during the snow free period and an underestimation during the snow covered period. However, agreement between modelled and measured temperatures improves for the snow covered period after a simulation period of about ten years.

An energy balance model of human metabolism developed by Hall et al. is extended to compare body composition outcomes among standard and proposed obesity interventions. Standard interventions include a drastic diet or a drastic diet with endurance training. Outcomes for these interventions are typically poor in clinical studies. Proposed interventions include a gradual diet and the addition of resistance training to preserve lean mass and metabolic rate. We see that resistance training, regardless of dietary strategy, achieves these goals. Finally, we observe that the optimal obesity intervention for continued maintenance of a healthy body composition following a diet includes a combination of endurance and resistance training.

The thesis deals with the tree energetic balance closely related to the phenomenon of plant transpiration. Living systems have a unique ability to equilibrate gradients in the nature. Storing energy of the incoming solar radiation into a latent heat of water evaporation is an example of such tree feature. It dissipates energy and simultaneously recycles nutrients and water in the ecosystem. There are few possible ways of energy balance detection shown in this work. The thermal imagining can be used as a method for an indirect indication of transpiration - transpiring plants have lower leaf surface temperature. An alternative method for determining the rate of transpiration is a direct measurement of transpiration on leaves or transpiration flow in a tree trunk. However, extrapolation of the above mentioned methods to entire stands can encounter some difficulties. The first part of the thesis presents a description of a physical background of energetic processes and the ways in which plants operate with water, the biotic pump theory is being discussed. The practical part begins with experiments on single leaves. These experiments are carried out to test the usability of the methods for the following experiments, which are performed on the entire living trees. They are focused on the relationship of the...

Le système endocannabinoïde est un acteur majeur de la régulation de la balance énergétique. Cependant, son rôle au niveau de l’hypothalamus, une région critique dans la régulation de la balance énergétique, reste méconnu. L’objectif général de ce travail de thèse a été de disséquer le rôle du récepteur aux cannabinoïdes de type 1 (CB1) exprimé par des populations neuronales hypothalamiques spécifiques dans la régulation de la balance énergétique et l’homéostasie du glucose en caractérisant trois nouvelles lignées de souris possédant une mutation conditionnelle de CB1. En régime standard, la délétion de CB1 dans l’hypothalamus induit une augmentation de la dépense énergétique et une baisse de prise de poids corporel sans modifier la prise alimentaire alors que la délétion de CB1 dans le noyau ventromédian de l’hypothalamus (VMN-CB1-KO) entraîne une baisse significative de masse grasse, une augmentation de l’oxydation des acides gras in vivo, une augmentation de l’activité du système nerveux sympathique (SNS) et un métabolisme du glucose périphérique amélioré. Enfin, la délétion de CB1 dans le noyau paraventriculaire de l’hypothalamus (PVN-CB1-KO) induit une baisse de poids sans modifier la prise alimentaire ni la composition corporelle. Lors de l’exposition à un régime riche en graisses, les souris VMN-CB1-KO prennent plus de poids et de masse grasse que les WT, tandis que les souris PVN-CB1-KO sont partiellement protégées de l’obésité alimentaire grâce à une dépense énergétique accrue.Ces résultats suggèrent que CB1 exprimé par différentes populations hypothalamiques joue un rôle différent dans la régulation de la balance énergétique, qui dépend aussi du régime alimentaire. / The endocannabinoid system is a major player in energy balance regulation. However, a complete understanding of its role within the hypothalamus, a region critically involved in energy balance regulation, is still missing. The general aim of this PhD work was to dissect the specific role of the cannabinoid type 1 receptor (CB1) expressed on different hypothalamic neuronal populations in energy balance regulation and glucose homeostasis by characterizing three new mouse mutant lines with a conditional deletion of CB1. On standard diet, CB1 deletion within the hypothalamus induced an increase in energy expenditure and a decrease in body weight gain without modifying food intake, while CB1 deletion within the ventromedial nucleus of the hypothalamus (VMN-CB1-KO) decreased fat mass, increased fatty acid oxidation in vivo and sympathetic nervous system (SNS) activity, and improved peripheral glucose metabolism. CB1 deletion within the paraventricular nucleus of the hypothalamus (PVN-CB1-KO) decreased body weight gain without affecting food intake or body composition. When exposed to a high-fat diet, VMN-CB1-KO mice gained significantly more weight and fat mass than their WT, while PVN-CB1-KO mice were partly protected from diet-induced obesity thanks to increased energy expenditure. These results overall suggest that CB1 expressed on different hypothalamic neuronal populations have distinct roles in energy balance regulation, which in turn also depend on the diet consumed.

Topic: Intervention Program for Weight Reduction in Adults Goals: The aim of this thesis is to devise as well as implement an intervention program covering exercise and dietary regimes for individuals that are overweight or obese. The goal also involves verifying the effectiveness by measuring various anthropometric parameters. Methods: The monitoring activities covered the period from 2.2. 2015 until 3.8. 2015. The intervention sample involved 9 individuals aged between 26 and 59. The sample was composed of three women and six men. The intervention program lasted for three weeks and I measured the weight using a normal personal weight and the waist circumference using a measuring tape. Results: The intervention program had a positive impact on the individuals that were involved. This resulted in decreased weight and a reduction in the weight circumference. The average loss of weight was 2.1 kg and the average waist circumference reduction was 2.4 cm. Thanks to the intervention program, the monitored anthropometric values were reduced. However, it also lead to the people achieving a better relationship towards physical activity and increased their awareness of the principles of a healthy diet. Keywords: overweight, obesity, physical activity, nutrition, weight, energy balance

[pt] O presente trabalho realiza uma comparação entre o ciclo Rankine tradicional e uma nova proposta de ciclo Rankine para uma planta de cogeração na indústria siderúrgica. O ciclo inovador é caracterizado por um sistema de regeneração por injeção direta de vapor seguida de bombeamento bifásico substituindo o uso de pré-aquecedores como no ciclo tradicional. Para a simulação dos ciclos de potência é empregado o Software Gate Cycle. São simuladas e estudadas diversas alternativas de configuração para a aplicação da nova tecnologia. A melhor alternativa de configuração do ciclo inovador é então comparada com o ciclo tradicional por meio da aplicação das análises de Primeira e Segunda Leis da Termodinâmica. Observou-se, entretanto, pouca diferença no desempenho do ciclo tradicional e do ciclo modificado. / [en] In the present work, a comparison between a traditional Rankine cycle and a proposed innovative Rankine cycle, for a cogeneration plant in the steel industry, is carried out. The innovative cycle is characterized by a regeneration system with direct steam injection followed by two-phase pumping, instead of the water pre-heaters used in the traditional cycle. Different configuration alternatives for the technology application were simulated and studied. The best alternative was then selected and compared with the traditional cycle using First and Second Laws of Thermodynamics analyses. Little difference was observed, however, between the traditional and the modified cycle performances.

No cenário mundial atual, em que é observado o aumento da população, da demanda por alimentos e da utilização de energia, também é observada a busca por fontes de energia alternativas às fósseis, diminuindo a dependência e risco econômico e ambiental oriundo de seu uso exclusivo. A análise de fluxos de energia possibilita uma avaliação da sustentabilidade de sistemas de produção agrícola, que visa o uso eficiente de insumos em termos energéticos. Essas análises também permitem identificar culturas como fonte de bioenergia, além de poderem ser utilizadas como complemento às análises econômicas, na busca por sistemas de produção mais eficientes. Esse estudo teve como objetivo apresentar uma análise do uso de insumos e energia, bem como a sua eficiência, em sistemas de produção de plantas forrageiras, tradicionalmente utilizadas para alimentação animal, na região dos Campos Gerais, Paraná. Foram determinados o fluxo de materiais (FM), demanda (EE) e disponibilização de energia (ES), balanço energético (BE), lucratividade energética (EROI) e energia incorporada (EI) da biomassa foram aplicados nesses sistemas. O FM determinou o consumo de insumos por área, e serviu de base para o cálculo da EE dos sistemas. Com características das culturas, calculou-se a ES, e com base nesses parâmetros, calculou-se os indicadores BE, EROI e EI. Com base nos resultados, concluiu-se que as culturas que se apresentaram mais eficientes do ponto de vista energético foram as gramíneas perenes, cultivares de P. maximum e Tifton 85, e as gramíneas anuais, milho e sorgo, pois apresentaram os melhores valores de indicadores da eficiência energética (ES, BE, EROI e EI), o que justificaria uma posterior investigação detalhada no uso energético dessas culturas. As culturas da aveia, azevém, cevada e milheto apresentaram os valores menos favoráveis no enfoque energético, portanto não adequadas à finalidade energética em relação às demais culturas estudadas. A operação que apresentou maior demanda de energia foi a distribuição de fertilizantes, devido aos insumos aplicados (mais que 47% da demanda total de todas as operações realizadas nas culturas). Os insumos que apresentaram maiores demandas de energia (mais de 57% do total) nos sistemas foram os fertilizantes, seguidos do diesel. Destacou-se o uso do fertilizante nitrogenado que representou mais de 50% da demanda total de energia em todos os sistemas de produção. O EROI para as cultivares de P. maximum, Tifton 85, milho, sorgo, milheto, azevém, cevada e aveia, foram: 14,2; 13,7; 10,1; 8,9; 7,2; 5,0; 4,6 e 3,8, respectivamente. / In the current world scenario, in which is observed the increase in population, demand for food and energy use, it is also observed the search for alternative energy sources to fossil fuels, decreasing dependence and environmental and economic risk arising from your use. Energy flows analysis enables an assessment of the sustainability of agricultural production systems, aiming the efficient use of inputs in energy terms. These analysis can also identify crops as a bioenergy source, and can be used as a complement to economic analysis, in the search for more efficient production systems. This study aimed to present an analysis of the use of inputs and energy, as well as its efficiency, in forage production systems, traditionally used for food, in the region of Campos Gerais, Paraná. Material flow (MF), demand (ED) and energy availability (EA), energy balance (EB), energy profitability (EROI) and embodied energy (EE) of biomass were calculated for all the systems. MF determined the inputs use per area, and was basis for the ED determination. With crop characteristics, EA was obtained, and based on these parameters, the indicators EB, EROI and EE were determined. Based on the results, it was concluded that the crops that were more efficient in energy terms were the perennial grasses, P. maximum cultivars and Tifton 85, and the annual grasses, maize and sorghum, since they presented the best values in the used energy indicators (EA, EB, EE and EROI), which would justify a further detailed investigation concerning the energy use of these crops. Oats, rye, barley and millet showed less favorable values, therefore not suitable for energy purposes in relation to other studied crops. The mechanized operation with the highest energy demand was the fertilizer distribution due to applied inputs (more than 47% of the total energy demand of all operations performed in cultures). The inputs that presented higher energy demand (more than 57% of the total) were fertilizers, followed by diesel, in all production systems. The use of nitrogen fertilizer is emphasized, since it represented over 50% of total energy demand in all production systems. The EROI for the cultivars of P. maximum, Tifton 85, maize, sorghum, millet, rye, barley and oats, were 14.2, 13.7, 10.1, 8.9, 7.2, 5.0, 4.6 and 3.8 , respectively.

A irrigação de pastagens no Brasil apresentou um crescimento acentuado nos últimos anos, porém devido a ausência de pesquisas sobre a aplicação de água em pastagens, o manejo da irrigação não vem sendo realizado de maneira racional. Os objetivos deste trabalho foram avaliar as relações entre a irradiância solar global e a radiação líquida sobre superfícies vegetadas com capim tânzania (Panicum maximum Jacq.) e com grama batatais (Paspalum notatum flugge); determinar a evapotranspiração do capim tânzania, por meio das medidas de lisímetro de pesagem; aplicar o método do balanço de energia para a estimativa da evapotranspiração do capim tânzania, por meio de um sistema automático de razão de Bowen; e comparar os valores de evapotranspiração do capim tanzânia, medidos em lisímetro de pesagem com os estimados pelo balanço de energia por meio de um sistema automático de razão de Bowen. O experimento foi conduzido em Piracicaba, estado de São Paulo. Por meio de um lisímetro de pesagem e um sistema automático de razão de Bowen foram obtidos valores de evapotranspiração do capim tanzânia (ETc). Também foram obtidos dados de irradiância solar global (Qg) e radiação líquida (Rn) sobre grama batatais e capim tanzânia. Os dados foram coletados diariamente e analisados, estatisticamente, mediante análise de regressão. Os modelos de regressão linear de estimativa da radiação líquida encontrados foram Rn = 0,5418.Qg (r 2 = 0,9297) para uma superfície gramada e Rn = 0,5613.Qg (r 2 = 0,8719) para uma superfície vegetada pelo capim tanzânia. A evapotranspiração média do capim tanzânia foi de 4,13 mm.d -1 , segundo o balanço de energia e 4,34 mm.d -1 , obtido pelo lisímetro de pesagem. Com base nos resultados, concluiu-se que o valores de evapotranspiração diários e horários do capim tanzânia medidos pelo sistema automático de razão de Bowen, foram afetados pelo efeito advectivo e pela precipitação, mas apesar disso houve uma razoável correlação com as medidas feitas em lisímetro de pesagem; e o estabelecimento das relações apresentadas neste trabalho mostra que os saldos de radiação em superfície gramada, assim como no capim tanzânia, podem ser estimados satisfatoriamente a partir da irradiância solar global, tendo a necessidade de se considerar suas variações sazonais. / Pasture irrigation presented a large growth in Brazil in recent years. However, the lack of research on pasture water use has led to inefficient irrigation management practices. The objectives of this work were: to evaluate the relationships between global solar irradiance and net radiation on surfaces covered with Guinea grass (Panicum maximum Jacq.) and Bahia grass (Paspalum notatum flugge); to determine the evapotranspiration of Guinea grass through weighing lysimeter measurements; to apply the energy balance method to estimate the evapotranspiration of Guinea grass by means of an automated Bowen ratio system; and finally to compare the evapotranspiration of Guinea grass measured by a weighing lysimeter versus the evapotranspiration estimated by the automated Bowen ratio energy balance system.. Evapotranspiration (ETc) was obtained for Guinea grass by means of a weighing lysimeter and an automated Bowen ratio system. Global solar irradiance (Qg) and the net radiation (Rn) over Bahia grass and Guinea grass were also obtained. The data were collected daily and statistically analyzed through regression analysis. The linear regression models for Rn estimates were Rn = 0,5418.Qg (r 2 = 0,9297) for a Bahia grass surface and Rn = 0,5613.Qg (r 2 = 0,8719) for a surface covered with Guinea grass. Guinea grass average evapotranspiration was 4.13 mm.day -1 by the energy balance method and 4.34 mm.day -1 as measured by the weighing lysimeter. The results led to the conclusion that the daily and hourly evapotranspiration values of Guinea grass obtained by the Bowen ratio automated system, were affected by the advection and by precipitation. Despite that, it was possible to obtain a correlation between the Bowen ratio evapotranspiration and measurements with the weighing lysimeter. The results show that the net radiation over Bahia grass and Guinea grass can satisfactorily be estimated from the global solar irradiance as long as seasonal variations are taken into account.