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1540 Uppsatser om Heat flow - Sida 45 av 103

Upplevd trafiksäkerhet med mittbarriär

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

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.

CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla

Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.

Undersökning av samband mellan MCV och geotekniska parametrar. Analys utifrån fält- och laboratorieförsök på finkornig jord

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.

Utredning av Aktiv designprojektet vid RV40. Inriktning mot utveckling av objektiv kontrollmetod med avseende på framtida funktion

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.

Viltbroar i Sverige. En jämförelsestudie på rörbroar av stål som alternativ till traditionella betongbroar vid uppförande av faunapassager

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.

Intern hantering som orsak till defekter: ett Sex sigma
projekt för analys och åtgärdsförslag på Sapa Heat Transfer AB

Detta examensarbete har utförts på Sapa Heat Transfer i Finspång och har tagit upp frågan med hur den interna hanteringen av produkterna kan orsaka defekter. I arbetet har en typ av defekt undersökts särskilt och denna defekt kan ses som ett exempel. Företaget tillverkar aluminiumband till värmeväxlare, främst till fordonsindustrin. Banden levereras på rullar med en diameter upp till 1700 mm, och en bredd mellan 12 mm och 1440 mm. Syftet med detta examensarbete är undersöka en defekt som är orsakad av den interna hanteringen, det vill säga det som sker mellan produktionsstegen.

Finansiella värderingsmodeller : En empirisk studie

This study tests two financial valuation models empirically by valuing three stocks from three industries, with the purpose of studying how well valuation models work empirically and to make a forecast. The models which will be tested are residual income valuation and discounted cash flow. Nine stocks will be picked strategically from the Swedish stock market and additional analysis will follow in the analysis chapter.Based on analysis and valuation, the commodities industry has decent valuation as the healthcare industry is undervalued thanks to the high valuation of AZN. The energy industry has low value due to the capital intensive nature of the industry. When it comes to the models and their practical implementation, DCF has been the most problematic to apply empirically whereas RIV was better but it still shows extreme values, which teaches the student the clear difference between theory and empiri..

Being the media : decentraliseringen av nyhetsproduktionen och dess effekter på tidningsjournalisters informationsbeteende

The Internet provides the common user with a variety of both traditional and non-traditional news sources, and a vast range of possibilities to contribute to the flow of information. By their participation in the production of information ordinary citizens can sometimes function as non-traditional news sources them selves and reach a potentially unlimited audience. The interactive nature of the Internet blurs the line between producers and consumers, and challenges traditional definitions of what counts as "news" as well as who qualifies as a "journalist". The main purpose of this thesis is to examine the potential consequences of this decentralization regarding the information behaviour of newspaper journalists and their perception of their professional role. The study consists of qualitative interviews with six journalists, employed by four of the leading Swedish newspapers, and a review of earlier research in the field.

Lärk eller Impregnerat ? en kvalitativt jämförande livscykelanalys av sibirisk lärk och svensk tryckimpregnerad furu

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.

The Current Emphasis : en diskussion om flödesfilosofi och planering

The current planning philosophy is based on a political utopic modernism founded during the first part of the 20th century. The focus is, in planning a defined area, to maximize the internal efficiency and to create a competitivesociety. During the latter part of the former century globalization changed the context, thus creating the need for a new way of approaching physical planning. This paper shows that the historical and philosophicalmetaphor of flow can be applied to meet the demands in the global city. It also shows how the edge, as where interaction takes place, is an important part of the content that has to be defined.

Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer

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.

Utveckling av modell för kvalitetsstyrning av polyetenreaktor

Allt större och större andel företag väljer att presentera och förmedla varor och tjänster via e-handel. En viktig aspekt vid e-handel är att kunden känner förtroende för e-handelsapplikationen och företaget. Denna rapport redogör för vilken inverkan multimediala inslag har för förtroendet av en e-handelsapplikation, vid initialt användande. En undersökning har genomförts med hjälp av en kooperativ utvärdering av fyra e-handelsapplikationer vilka innehåller olika typer av multimediala inslag har.Resultatet av undersökningen visar att multimediala inslag inverkar positivt på förtroendet för e-handelsapplikationer. Däremot finns indikationer på att för hög grad av multimedialt inslag inverkar negativt på förtroendet för e-handelsapplikationer..

Hur upplever elever raster? : En fenomenologisk studie

The essential thing about breaks has been in relation to time, body, movement, force and room during my examination. Through conversations high-school students from two schools have taken part in this study. The examination is based on conversations with the students and has focused on students? experiences of breaks, and is also carried through by the method of phenomenology. The results of my studie show that students - during their breaks - experience a feeling of allways heading for something and also that time seem to exist in three levels: filled time, non-filled time and flow regarding of time.

Framtagning av ett nytt recept för clear-coat batter av pommes frites : En teknisk och sensorisk utvärdering

The requirements of good quality and appetizing fast food increases continuously as a consequence of a community where food is always available. The crispiness of French fries is an issue that must be considered in this context, since it tends to decrease and give the fries a soft surface not appreciated by the consumer. To prolong the crispiness, the fries can be coated by a batter, a mix of starches. The batters used often consists of modified starches, e.g. cross-linked, acetylated and dextrinizated to increase and prolong crispiness, flour to stabilize the batter and sodium bicarbonate to make the batter ?rise?.The cross-linked starch keeps the granules in a swelled state and prevents them from breaking when exposed to heat or processing: therefore, it delays the gelatinization and decreases the stickiness of the batter.

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