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983 Uppsatser om Heat transfer - Sida 30 av 66

?Var är du?? En studie om virtuella kollaborativa designprocesser i en studiemiljö

The design process of an interaction design student is mostly collaborative and computer oriented. Based on this, it?s hard to believe that we have not yet found a tool that will facilitate our needs. With this in mind, which elements do we need to promote collaboration in a virtual design process? This thesis will include design processes, collaboration, creativity and virtual awareness, amongst others.

Underlag för bedömning av energibrunnar inom vattenskyddsområde

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Smarta lokala energisystem, Vision-Teknik-Tillämpning

The energy sector is facing an impending paradigm shift. Today?s technology enables the end-user to generate their own energy locally at home. Furthermore, recently developed storage technologies make it possible to balance energy demand with stored energy and integrate district heating with the local power grid. This means that in the future heat and electric power will interact and energy flows is converted over energy boundaries.

Effektmätning i pump

The interest for power and energy measurement has greatly raised with todays increasing electricity prices and enviromental awareness. In the search for energy efficient solutions, the measurements are more complex due to increasing of non linear components. Harmonics and non sinusoidal voltages put high demands on sampling and filtering. Meanwhile, the price must be controlled so the customer still will find it interesting to invest in smaller plants. ITT W&WW asks for a robust, heat resistant power meter with compact dimensions to allow mounting inside the casing of a pump.

Webbläsartillägg för inhämtning av data

Speedledger is a company that is working to automate electronic accounting for businesses, organizations and associations.In the current situation bank data is sent from the users internet bank to Speedledger via a virtual printer driver. The driver transforms the web page into a PDF and sends it to a server for interpretation.The problem is that PDF is not created for this sort of data transfer and makes the interpretation of data is very problematic.The goal of the thesis is to study whether there is a possibility to develop a browser add-on that can retrieve information on the customer's banking page and send it on to Speedledgers server for interpretation. My task was to implement a add-on for one of the three major browsers Mozilla Firefox, Google Chrome or Microsoft Internet Explorer, and then study the possibility of implementing it to the other two by reading the documentation.What I concluded was that it is possible to implement for all the three browsers. However, the techniques will differ slightly when developing these add-ons.  .

Island - det andra och det samma : Uno von Troils Bref rörande en resa til Island MDCCLXXII som kunskapsförmedling

The purpose of this paper is to study Uno von Troil's book Bref rörande en resa til Island MDCCLXXII as part of the transfer of knowledge about Iceland to Sweden and Europe during the late 1700s. On the basis of discussions on travel books and the image of 'the other', 'I will argue that von Troil, using the skills he already had access to, as well as the skills he acquired after his trip, provides a multifaceted picture of Iceland. At the same time, I will examine how von Troil conveys information about Iceland both to a Swedish and a European audience and illustrate his network relationships and career aspirations..

"Andra människors krig" : En analys av rapporteringen kring det första Tjetjenienkriget sett ur tre svenska tidningar

Detta examensarbete är en undersökning i hur riktlinjer anpassade för Serious Games-genren kan användas i utvecklingen av träningsmoment till ett simpelt kooperativt plattformspusselspel. Undersökningen baserades på en analysmodell vid namn RETAIN (Relevance, Embedding, Transfer, Adaptation, Immersion, Naturalization) vilken utvecklats specifikt för att analysera och hjälpa till vid utvecklingen av inlärningsspel. Denna modell har använts för att analysera plattformspusselspelet Braid, varefter analysen har använts som riktlinjer under utvecklingen av ett eget verk. RETAIN-modellen har även använts för att analysera det egna verket.Efter undersökningen har jag kommit fram till att RETAIN-modellen i sitt originalutförande ej lämpar sig för utveckling av träningsmoment i underhållningsspel då kraven på spel i Serious Games-genren och underhållningsspel är alltför olika..

Relationen mellan cyklister och fotgängare vid Södra Älvstranden, Göteborg En utvärdering av trafiken på cykelstråket Älvsborgsbron - Centrum

This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..

Utvärdering av energieffektiviseringsåtgärder på Bokelundskolan i Växjö

The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.

Solenergi på Kvarnholmen

In recent years it has become more and more evident that man has contributed to much of the climate changes that have taken place during the last century. A major challenge today is to reduce emissions and energy usage at the same time as the global population is growing. To contribute to a better environment, Stockholms Stad has set at target of becoming fossil fuel free by the year of 2050. The construction of new districts is done with this goal in mind; energy efficiency and renewable energy sources are examples of methods to achieve this.Solar energy is considered to be a sustainable energy source and the most common techniques to harvest solar energy in Sweden are solar cells and solar collectors which produce electricity and heat respectively. This report aims to investigate whether an investment in any of these systems would prove to be economically beneficial at Kvarnholmen, a district under construction in eastern Nacka, Stockholm.Since the finished blueprints only cover a small portion of Kvarnholmen, the report examines the possibilities for a house where construction has already begun, Nya Kvarnen.

Utveckling av dataanalysprogram för Opcon Powerbox

Opcon Powerbox is a product developed by Opcon together with the underlying company SRM (Svenska Rotor Maskiner) where surplus heat from the industry is used through an Organic Rankine Cycle (ORC)?process to produce electricity. An ORC-process is a thermodynamic circle process in which a refrigerant is used as the working fluid. The refrigerant makes it possible for the circle process to operate at lower temperatures than the conventional Rankine process.In this master?s thesis a data analysis software for the Opcon Powerbox has been developed in which measurement data is retrieved and handled from the Opcon Powerbox.

En studie av ett grupporganiserat lärande

The sun is an endless energy source and the heat it produces can be used to heatup our homes. This technology is relatively old and was introduced in the late70-s. There are two kinds of solar collectors that are most frequently used todayand these are plain solar collectors and vacuum solar collectors. The plain solarcollectors are the once that are used the most but the vacuum solar collectorshave increased more as a percentage the last couple of years.The biggest question asked regarding an investment in solar heating is if theplant is economically profitable. This question has no direct answer because itis dependent on a couple of prerequisites.

Kunskapssyn och behov av IKT - verktyg

The sun is an endless energy source and the heat it produces can be used to heatup our homes. This technology is relatively old and was introduced in the late70-s. There are two kinds of solar collectors that are most frequently used todayand these are plain solar collectors and vacuum solar collectors. The plain solarcollectors are the once that are used the most but the vacuum solar collectorshave increased more as a percentage the last couple of years.The biggest question asked regarding an investment in solar heating is if theplant is economically profitable. This question has no direct answer because itis dependent on a couple of prerequisites.

GALS,Design och simulering för FPGA med VHDL

Heat, clock scew and frequency optimization are some of the problems a semiconductor designer must face. By splitting a synchrounous block into multiple pieces which comunicates asynchronously with eachother and provide them with independent clocks, these problems may be reduced. GALS (Global Asynchronous Local Synchronous) is a wrapper that wraps a synchronous block and provides it with a clock. Multiple GALS-elements will make the whole system. The clockfrequency may be independently adjusted between each block.

Mail Exchange Protocol (MEP): Ett utkast till nytt protokoll för elektronisk post

SMTP, the current protocol for sending electronic mail (e-mail) over the Internet, has for many years suffered from several problems and limitations. When it was designed, well over twenty years ago, the requirements for e-mail were very different from those of today. A message was a text message in English, and both user and machine were explicitly named in the address. The protocol was not designed to transfer other types of messages, and no mechanism was included to verify the identity of the sender.In order to solve these shortcomings, a new e-mail protocol needs to be defined. This report specifies a basis for what such a protocol may look like.

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