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1483 Uppsatser om Water vapour transmission - Sida 55 av 99
Väggjutning med självkompakterande betong : Vad påverkar gjutresultatet?
AbstractThis master thesis was performed at Scania transmission department in Södertälje, where the manufacturing of gears is done. Today a large amount of manual handling is performed between the machining and the hardening process. Most of the manual handling is done at the heat treatment department. The purpose of this master thesis is to give a suggestion on how to reduce or eliminate the manual handling at the heat treatment department. The possibility to use the same packaging throughout the processes will also be investigated.
Torsionsanalys av vevaxeln kamaxeln och motortransmissionen på Scanias D12: a
Syftet med examensarbetet är att ta fram en modell för torsionssvängningar i systemet vevaxel, motortransmission och kamaxeln på SCANIA's 12 liters dieselmotor DC1201. Det höga gastrycket och injektortrycket på SCANIA's dieselmotorer ger upphov till stora moment på både vevaxeln och kamaxeln. Dessa moment varierar kraftigt med tiden och skapar torsionssvängningar hos de båda axlarna samt hos motortransmissionen. Modellen som presenteras är linjär och av frekvens respons typ, den beskriver förloppet i fortvarighet. Axlarna och transmissionen är diskretiserade med totalt 37 frihetsgrader.
En jämförande studie kring några av dagens produkter inom Store and Forward och Live
SVT is Sweden?s largest TV-network and broadcasts more then 22 000 hours of TV each year. SVT is a public service company where the basic idea is to reflect the world from different perspectives and news is very important for providing neutral and versatile information in a variety of areas. An important part of the flow of information is to continuously receive reports from all corners of the world around the clock. This places very high demands on the technology used and it is important that it function and develops to meet current and future growing needs.
Ett träd och dess liv : Förskolebarns uppfattningar om träd
The aim of this study was to investigate preschool children's perceptions of trees in and it was done through qualitative interviews. The children were drawing trees and told me what the tree needs to grow and what happens to the leaves in autumn. In a playful way, they learned more about trees and the purpose was also to examine whether they had acquired new experiences and thoughts on the trees, photosynthesis and decomposition. Then the children were interviewed again to see if their answers were different. The results showed that the children gave different answers at the second interview.
Hiv i Sverige - Prevention, sexuella attityder & beteenden
ABSTRACT. Introduction: Human Immunodeficiency Virus (HIV) is a retrovirus which occurs worldwide and spreads between humans mainly through sex, from mother to child, blood and blood products and between injecting drug users. After been infected with HIV for a couple of years the final stage of the infection progress into Acquired Immune Deficiency Syndrome (AIDS), and there is no cure or vaccine, only medication that delays the development of the disease. Objective: The aim of this thesis is to examine the preventive work against HIV in Sweden, the groups at risk for getting infected and to highlight sexual attitudes and behaviours among adolescents and young adults. Method: A literature based study method was used and the material is based on scientific articles and reports from active actors within the field of HIV prevention.
På jakt efter den produkt som flytt - en studie om uppskjuten produktlansering och dess effekter
Many product launches are postponed today, however very little research regarding to customer responses to such events has been carried out. The purpose of this paper is to investigate how people react to a postponed product launch. An experimental study of responses to a postponed launch of a mobile phone, a mineral water and a music album is used to investigate customer reactions. The respondents exposed to the postponed launch showed a higher value of reactance. This reactance affects the attitude, purchase intention and perceived quality of the product in a negative way.
Design och konstruktion av mätuppställning för induktiv mätning av magnetisk spinndynamik
Development in spin dynamic occurs in the whole world because of therising demands on fast electronic storage for example hard drivesand RAM (Random Access Memory). Measuring the spin resonance of amaterial gives you the insight of the theoretical speed for amagnetic memory. This means the maximum storage speed is below thefirst resonance. All magnetic materials have different propertiesthat will inflict the resonance frequency which brings that theconstructors of memories need to know which magnetic material theywill use to obtain best results. In the market for normal users themaximum storage speed in a RAM memory is 1.6 GHz.
Screens : tävling om strandpromenaden i Helsingborg
The competition for the beach promenade in Helsingborg was announced in 2001 and was arranged by the city of Helsingborg. My contribution to the competition represents the main part of my thesis in the Landscape Architecture Programme.
The competition entry is based on the concept of crossing screens of vertical elements which connect the pattern and structure of the city to the beach and the water. The different materials and designs of the screens relate to the various characters of the different parts of the area and they form a sequence and uniting theme along the beach.
In addition to the competition entry which was made in 2001, the thesis contains a second part, made in the spring of 2006. It consists of an Introduction with the competition programme and a description of the starting points, a part called Method where the process is described, and the Conclusion with reflections on the competition entry and the process where I also introduce and comment on some other projects which in different ways have are connected to my concept.
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BAMBUVISKOS ? En hållbar fiber för framtiden?
Naturskyddsföreningen gav författarna uppgiften att undersöka förekommande viskosprocesser och alternativa regenereringsprocesser, detta för att identifiera hur hållbara de är ur ett miljöperspektiv och vilka processer som går att applicera på bambu. Detta för att se möjligheten att märka bambuviskos med Bra Miljöval och för att klargöra frekvent uppkommande frågor angående bambuviskos. Syftet är att se på de olika processernas kemiska innehåll samt vilka utsläpp de orsakar till luft och vatten. Ett delmål med rapporten är att den ska kunna användas som material vid vidareutveckling av kriterierna för Bra Miljöval Textil. Resultat som erhållits vid jämförelser av studerad litteratur är att de betydande faktorerna för miljöpåverkan från massaframställningen samt viskos- och lyocellprocessen beror av: använda kemikalier i processen, energianvändningen och vilken typ av energi, möjligheten till rening av utsläpp till luft och vatten samt återvinning av energi och kemikalier.
Hantering av kugghjul : -Vägen från mjukbearbetning till hårdbearbetning
AbstractThis master thesis was performed at Scania transmission department in Södertälje, where the manufacturing of gears is done. Today a large amount of manual handling is performed between the machining and the hardening process. Most of the manual handling is done at the heat treatment department. The purpose of this master thesis is to give a suggestion on how to reduce or eliminate the manual handling at the heat treatment department. The possibility to use the same packaging throughout the processes will also be investigated.
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..
Optimering av informationsinsamlingvid prototyptillverkning
This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.
Tillförlitlighet i Stockholms elnät : En analys med hjälp av Tekla NIS
Outages in the electric grid can be costly for society. Because of this, reliability is one of the parameters used to regulate network companies. Reliability in electrical grids can be measured with SAIDI, system average interruption duration index, which for Fortum Distribution has increased in Stockholm?s distribution network (11 kV) in the early 2000?s.By using outage data for Stockholm from 2011-2013, sets of parameters to be used for reliability calculations in the network information program Tekla NIS were derived. Two different options for investment were then analysed: changing old cables with high fault frequencies, and installing automatic switching in distribution substations.
Ny stamstation i Yttermalung för anslutning av vindkraft : Nätstudie av olika utföranden i normal- och reservdrift
Since 2004, wind power has had the largest installation of new capacity compared to other energy sources in Sweden. Accommodating new wind power may require strengthening or rebuilding of the existing grid in areas where the grid is already loaded to maximum capacity. This master thesis examine the possibility of a new 400/130 kV substation in Yttermalung, Sweden, with a connection to the two neighboring regional grids in Dalarna and Värmland owned by Fortum. This substation would provide a new connection point to the Swedish transmission system as well as an interconnection of the two, currently separated, regional grids. Different expansion scenarios where a substation with and without series compensation or a phase shifting transformer (PST) to control active power flow were studied.
Fisksamhället i Spexhultasjön, Nässjö
The lake Spexhultasjön is a moderate humic mesotrophic lake that is not acidified. The fish fauna was investigated by using a standard method for sampling freshwater fish with multi mesh gill nets. The fish fauna was diverse with perch, pike, tench, common whitefish, and roach. Perch and roach dominated. There were few pikes.