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957 Uppsatser om Thermal heat losses - Sida 35 av 64

Opera i Stockholm, Galärvarvet

Suggestion for a new operahouse in stockholm, förslag på nytt operahus i stockholm. Stockholmsoperan..

Portrycksvariationer i lera - Simulering av portrycksvariationer i leror underlagrade av friktionsmaterial

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Västlänken, Citytunneln och Citybanan En jämförande studie mellan de samhällsekonomiska analyserna

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Tidsuppskattning av ritningar i byggkonsultbranschen. En utredning baserad på genomförda projekt hos en byggkonsultfirma

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Biobränsleanvändning och Flameless oxidation i degelugnar för glassmältning

Idag värms glasugnar upp med antingen gasol eller olja, detta projekt vill visa på möjligheten att istället använda gas från biobränsleförgasning som förbränns utan synliga flammor. Detta skulle miljömässigt ge fördelarna att biobränslen inte bidrar till växthuseffekten och ge förutsättningar för att minska kväveoxidutsläppen genom bättre teknik än dagens.För att visa att det är möjligt att både behålla produktionen och reducera kväveoxiderna med förgasningsgas konstruerades en modell av ugnen och strömningsbilden studerades i vattenmodell. För att undersöka värmeöverföringen i ugnen behöver en eller flera kalorimetrar konstrueras för att kunna användas vid varma försök. Dimensionsberäkningar gjordes som visade att detta är möjligt med vissa typer av kalorimetrar..

Quantitative thermal perception thresholds, comparison between methods

Skin temperature is detected through signals in unmyelinated C-fibers and thin myelinated A?-fibers in the peripheral and central nervous system. Disorders in thin nerve fibres are important and not rare but difficult to diagnose by the most common neurophysiological methods. In this pilot study different methods for quantitative sensory testing, QST, were compared to give some ideas about which method could be the most efficient to use in order to point out injuries of the sensory system in clinical practice. The comparison was made between Békésy (separate warmand cold thresholds) and Marstock test (combined warm and cold thresholds).

Personlig hygien på stycknings- och charkanläggningar : hur personalen på tre anläggningar följer och ser på rutiner för personlig hygien

Microwave is a time- efficient device for heating and reheating of foods. Despite the fact that its effects on foods have been evaluated during a long period of time, without any more negative effects shown compared to conventional cooking, one third of the Swedish population believes (in 2010) it accounts for a higher loss of nutrition. This literature review aim to compile studies regarding how food is affected by cooking in microwave, with respect to cooking losses, nutrition, secondary metabolites as well as sensory and textural aspects and compare it with conventional cooking. The compilation shows that different combination of effect (W), time and amount of water during microwave cooking have different effects on foods. The contents of proteins, vitamin B and carbohydrates are generally higher after microwave cooking, while anti-nutritional substances are affected much less during conventional cooking. This also depends on if it is of animal or non-animal origin. However, for the majority of nutrition values the differences are quite small.

Nya renings- och uppgraderingstekniker för biogas

Biogas is a renewable energy source that is produced by anaerobic digestion of organic mate-rial. In Sweden, biogas predominately comes from sewage water sludge and landfills or from organic waste of households and industries. Small scale digestion plants at farms are espe-cially expected to contribute to increased biogas production in the future. Biogas can be ob-tained directly in it?s raw form and used as fuel in a combustion chamber.

Jämförelse mellan olika material i spåröverbyggnadens bärlagerbärighets- och materialprovning av spårväg i Göteborg

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

?Attack är bästa försvar? : en kvalitativ intervjustudie med före detta mobbare

The objective of this study was trying to understand bullying focusing on the bully. The questions at issue were: What can contribute in the making of a bully? What are the benefits and losses in bullying? What are the former bullies? thoughts on bullying, now in comparison to in their youth. This was investigated with a qualitative approach from a former bullys perspective, hence three former bullies were interviewed. The result was presented in themes and was then analysed from a social psychological and social constructionist perspective.

Elektrifiering av jordbruksmaskin : Direktkoppling till solföljare och elnät

The agricultural sector is currently highly dependent on fossil fuels, with diesel beingmost prominent. There are however both historical and modern alternatives thathave not been subject to enough evaluation to disregard them as suitable alternative.This report aims to theoretically investigate the feasibility of converting aconventional diesel driven tractor to run on electricity, delivered via a cableconnected to either the main power grid or on-site electric production, such asphotovoltaic. Delivering electricity to the machine via a cable is a method withhistorical roots in the early 20th century and in the present day mining industry.The economic and technological potential of the technique are evaluated, along withthe examination of several different motor powers, voltages, losses and constructionideas. The report finds the technique to be both possible as well as long termeconomically and environmentally beneficial. To realise this method however, somedeviations from the present methods of agricultural farming must be made,considering the more advanced driving patterns, the limited mobility and therequirement for extra driver awareness.

Passivhus det långsiktiga valet. En konkret jämförelse mellan konventionellt byggande och passivhus

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Incitament för förbättrat miljöarbete. En studie av miljöarbete I relationen mellan beställare och entreprenör

This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.

Sjuksköterskors upplevelser av att ge stöd till anhöriga inom den palliativa hemsjukvården : En intervjustudie

 The purpose of this study was to investigate registered nurses experiences about giving support to relatives to patients within palliative home care. This study was descriptive with qualitative approach. The data collection was made in the form of semi structured qualitative interviews which took place in a Swedish city of medium size, in an area for palliative homecare. Six registrated nurses were interviewed which all gave informed consent. The study suffered no losses and permission from the director of the concerned department had been given prior to the start of this study.

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

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