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1394 Uppsatser om Air volume flow - Sida 54 av 93

Kappa Control with Online Analyzer Using Samples from the Digester's Mid-phase

In the pulp industry, digesters are used to disolve lignin in wood chips. The concentration of lignin is measured and is called the Kappa number. In this thesis, the question of whether an online Kappa sensor, taking samples from the mid-phase of the digester, is useful or not is analyzed. For the samples to be useful, there has to be a relationship between the measured Kappa at the mid- phase and the measured Kappa in the blowpipe at the bottom of the digester. An ARX model of the lower part of the digester has been estimated.

Energikartläggning av polishuset i Gävle : Åtgärdsförslag för ett minskat energibehov i fastigheten Gävle Söder 17:10

The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.

Transientanalys för Forsmark block 2 och 3 : Studie av hur val av driftpunkt och pumpreglering påverkar torrkokningsgränsvärdet

The dry out criterion (MCPR) has been calculated for the most limiting H2-events for Forsmarks unit 2 and 3, at operating points that are normally not analyzed before each cycle. The operating points that normally are regarded as the ones with the lowest margin to dry out are the ones where the thermal power is the highest at agiven recirculation flow. This report shows that this is not the case for Forsmark 3. MCPR-values at partial power operating points are higher for the limiting case inside rather than on the boundary of the region of operation. It is therefore recommended that the method for determining the dry out criterion for Forsmark 3 is revised to account for this effect.

Osäkerhet i energisimuleringar av flerbostadshus : Analys av fem nybyggnationer

Since energy simulations are used to verify that projected residential buildings will reach the current energy requirements it is important that the results are reliable.This report investigates the extent of uncertainty in energy simulations, estimates the causes of the uncertainty and its economic and environmental consequences.The method used in this report is based on three validation methods; empirical validation, analytical validation and comparative validation. The analysis was carried out for five multi-family dwellings in Uppsala with installed meters for energy measurements. One of these objects, Klockarlunden, was studied in more detail than the others.The results show that the deviations are between 10 and 29% for the studied objects, which means that the uncertainty is estimated to be at least 29%. All simulations underestimate the buildings need of energy. The simulation for Klockarlunden can predict the energy consumption to be within the range of 46-98 kWh/m2year with 90% confidence level based on the current uncertainty.

New Business Model for District Heating Firms Stabilizing the National Energy System with a Future Variable Electricity Production

The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.

Vilka faktorer bidrar till att spelare fastnar i MMORPG spel?

Massiva onlinerollspel är idag mycket populära och försäljningen och spelandet utav dessa ökar markant. I och med detta väcks frågan om vad det är i dessa onlinespel som gör att människor spelar och fortsätter spela. Denna uppsats inriktas främst mot MMORPG:s, Massively Multiplayer Online Role-Playing Games, då författarna anser att det är i denna onlinespelsgenre den största möjligheten att finna och definiera de faktorer, som påverkarspelares vilja att spela, finns. För att ta reda på dessa faktorer skapades en enkät vars frågor utformades med en gameflowmodell i baktanken. Denna enkät lades sedan ut på sex olika onlinespelsanknutna forum, där totalt 105 spelare anonymt deltog.

?Det sade bara klick?: en studie om 15-åriga tjejers Internetanvändning utifrån ett källkritiskt perspektiv

This Masters thesis aims at investigating how 15-year old girls use the Internet, particularly on their free time, taking a source critical perspective. It includes group interviews. The main question of this thesis was whether there is a need for specific user education. The following four questions were asked: What do they do on the Internet during their free time? In what way do the girls learn how to interact with each other on the Internet? How do they relate to different types of web pages and materials from a source critical aspect? What content do they consider to be relevant in a user education? The study is mainly focused on information use and information behaviour in different contexts.

Hur skall skogen skötas? ? en analys av skogsfastigheten Fagerdal 2:10 i Jämtland

The forest property Fagerdal 2:10 was donated to the Swedish University of Agriculture in 1995 by Erik Rönnberg. The dominating species is Norwegian spruce (Picea Abies) and the average age is high due to selective cutting. The aim of this study has been to analyze how the forest on the property should be managed and demonstrate how a better estimated forest data affects the future management. The impact of the management on the carbon stock of the property was also examined. A forestry plan established in 2009 by Skogssällskapet was used as a basis for the analyses.

Re-design av BEV-heater

Denna rapport beskriver det examensarbete som utförts på Calix AB under vårterminen 2013. Calix AB tillverkar värmare för bland annat batteri och kupé till fordonsindustrin. Uppdraget i detta examensarbete var att göra en omkonstruktion på BEV-heatern (Battery Electrical Vehicle) som är en batteri- och kupévärmare till el och hybridfordon. Problemet med den nuvarande konstruktionen är att den bygger på delar från äldre värmare till fordon med förbränningsmotorer, samt att konstruktionen inte är lämplig för produktion i större serier. Krav som Calix AB hade var:Integrerat ChassiMinimera tryckfallUnderlätta montering och tillverkningUppfylla standarder satta av fordonsindustrinKunna monteras ?in-line? i fordonetFör att kunna genomföra projektet var vi till en början tvungna att få kunskap om hur den befintliga BEV-heatern fungerar.

Produkthantering vid tillverkning av roterande verktyg

AB Sandvik Cormorant?s production unit in Gimo has identified a need to examinethe handling of products between operations with the purpose of generatingproposals of improvement for the product handling.The aim of this project is to study the existing manufacturing process and givesuggestions for improvement. The proposals should reduce the manual handling ofproducts, decrease the risk of damaging the products during the manufacturing andform a basis for increased traceability. Based on a mapping of the manufacturingprocess and the problem description, a specification of requirements has beencomposed.The mapping of the manufacturing process suggests that a change of the currentsystem is required. The company is recommended to decide how the producthandling between operations should be performed as guidelines for the productionteam.

Panic - IT-stress och Design med hälsa i tanken

Från början hade vi ställt in oss på att vi ville hitta ett nytt sätt på hur man kan designa IT-relaterade produkter med ungdomars välmående och hälsa i tanke. Detta visade sig inte vara den lättaste uppgift två interaktionsdesigners, utan någon som helst bakgrund eller insyn om människors välmående, kunde tänka sig. Efter mycket efterforskning både i böcker och på Internet började vi förstå att vi inte var ensamma i vårt mål att motverka att stress uppstår i relation till dagens informations teknik. Flera andra forskare med bakgrund inom sjukdomar, rehabilitering och medicin hade varit aktiva inom fältet men bara ett fåtal interaktionsdesigners innan oss hade försökt sig på något liknande. Vi fick mycket inspiration från deras tidigare projekt och vi har försökt använda oss utav deras kunskaper och resultat.

Investeringskalkyl för en ny såglinje : en rapport om investeringskalkylering

This report presents an investment calculation based on an assumed initial investment of a new saw line to an existing sawmill. In order to get as close to reality as possible, we have received data material from northern forest owners who recently made an initial investment in their sawmill in Kåge. In order to calculate and evaluate investments are several different methods, but we, we have chosen to use the discounted cash flow method. The method sums up with the help of a fixed cost of capital together with any future costs and revenues, thereby giving a present value of the investment. We also do a sensitivity analysis to examine how selected factors affect the investment research they change. The study is carried out to a fictitious investment, and therefore the result should not only be studied as a result of the figures. The purpose of this study was that with the help of an investment calculation studying the profitability of a hypothetical investment, and by means of a sensitivity analysis to study the sensitivity of investment to changes. The result demonstrates that the calculations according to the present value method requires a lot of information of the prospective investment.

Miljöpåverkan av äggproduktion : En jämförelse mellan Lilluns ägg och andra svenska äggproducenter

The purpose of this report was to compare Lilluns egg production with other Swedish egg producers based on the flow of nutrients (nitrogen, phosphorus and potassium) in the egg production systems. The main focus in the report was the utilization rate of the forage and the excess of nutrients per kg egg. Additionally, the purpose was to identify the environmental impact from Lilluns egg production and compare the results with other egg producers. The inflow of nutrients associated with forage and poultry was compared with the nutrients that were exported from the production. All of the egg producers in this study had an excess of nutrients.

Mjölkböndernas åsikter om VikingGenetics nya produkter X-Vik och GenVik

VikingGenetics is one of the world's largest breeding companies. 2008 was launched two new products, X-Vik and GenVik. Now VikingGenetics want to get information about the effects of the marketing. We have investigated the differences in knowledge and use of the products between different livestock associations, size of herd and farmers' breeding interests. The method used was by sending out a questionnaire by mail.

Kvantifiering av osäkerheter i lyftkraftsmodellen

With today´s power uprates in BWR reactors the bundle lift force has become aproblem. The lift force is calculated using a best estimate approach and the resultfrom the calculation should pass the existing lift force margin. Lift force margin isdefined so that the lift force may not exceed 80 % of the fuel weight. The margin issupposed to cover all the uncertainties that exist in the lift force calculations.However, no uncertainty analysis has been conducted to quantify the uncertainties.In this report the uncertainties in the lift force model have been quantified. Each inputparameter to the lift force model which has been assumed to have an uncertainty isassigned a probability distribution.

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