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1615 Uppsatser om Two phase flow - Sida 56 av 108

Aktiv bullerdämpning i ventilationssystem

Active headsets have been on the market for years and now it is time for something else to enter the stage. The technology of active noise reduction can for exmple also be used in ventilation systems for reducing ventilation noise. An active control system principally consists of four important components, namely the downstream error microphone, the upstream detection or reference microphone, the digital signal processor (DSP) and a loudspeaker. The upstream reference microphone listen to the primary ventilation noise and sends it to the DSP which makes a phase shift to the signal and sends it to the loudspeaker. The loudspeaker sends out the opposite waveform of the incoming one and reduce the primary ventilation noise.

Förbättrad Kravhantering med hjälp av Lösningsinriktad Pedagogik

Abstract The purpose of writing this thesis was to improve methods during requirements engineering phase. Usercentred system engineering has some problem areas, which are examined and verified to create a new guideline for developers. This guideline tends to make requirements engineering more effective and help developers create more concrete requirements. It is not uncommon that system development projects ends up with unsatisfied users or delay in deliveries. The reasons are different kinds of communication problems between users and developers during verification of requirements. There is a therapy model, called solution-focused therapy, used in family and individual therapy. The model focuses on solutions for the future instead of problems in the past.

Användning av könssorterad sperma i nötkreatursaveln :

Almost for as long as there has been breeding on bovine species, there has been a wish to have a higher proportion of offspring of either one or the other gender. In dairy cattle, heifers are more valuable, while in beef stock bulls are preferred. Semen is sorted based on the difference in DNA content between the X- and Y-chromosome in the genome of the sperm. X-chromosomes contain on average between 3,70 to 4,22% more genetic material than the Y-chromosome. Commercially it is the method of flow cytometry that is being used, which is always under improvement.

Ungas val av fritidsaktiviteter : en studie på vilka faktorer som föranleder valet av fysiskaktivitet

Denna uppsatts består av en kvantitative enkät studie som genomfördes på två högstadieskolor i mellan Sverige under våren 2012. Syftet med uppsatsen är att få en inblick i vad som ligger bakom elevers val av fritidsaktiviteter och då mer precis val av fysisk aktivitet samt att undersöka skolans, och då främst ämnet idrotts och hälsas, roll i elevernas val av aktivitet. Bakgrunden till rapporten kommer från formuleringarna ur lpo 94 och lgr 11 som betonar att ett syfte med ämnet är att främja Idrott och hälsa ämnets uppgift att främja fysisk aktivitet på fritiden. Vi analyserar tidigare forskning som bland annat har undersökt den störta föreningsidrotten som utgörs i Sverige och vad det kan finnas för faktorer till att ungdomar utför den. Tidigare forskning som används i rapporten är bland annat från venska riksidrottsförbundet och ungdomsstyrelsens rapport om unga och föreningsidrotten.

Lärmiljöer och lärare - En studie av hur lärares undervisningsfilosofi präglar arbetet och elevers lärande vid en Musikskola

Title: Teaching environment and teachers. A study of how music education philosophies influence instrumental teaching and learning at a community music school. Question of the research: Which Music philosophical ideas can be traced in the instrumental teaching of a community music school? Two teachers and their students have been videotaped. Data from the tapes and from interviews with the teachers and students have been analyzed by means of a category system, which grew out of the theoretical overview.

Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie

The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..

EW26 : Drivanordning för vertikaltgående fönsterpartier

EW26 is a Bachelor thesis carried out by students, Jessica Blomberg, Sara Danielsson and Mikael Johansson, during the academic year 2010-2011 at the Innovation Engineering Program of Halmstad University. The project was conducted in close cooperation with Ergosafe AB.Ergosafe develops, manufactures and sells electric sliding windows. Due to the company?s current expansion phase they want to increase their product range. The company has identified a need for large windows that moves vertically.

Individuell mätning av hushållsavfall i flerbostadshus : ?Ett incitament för minskad klimatpåverkan?

The electric vehicle market has potential to contribute to Sweden?s national goal to have a fossil fuel independent transport sector by 2030. However, the market answers to a lot of challenges making it difficult for the market to fully reach its potential. The volume of electric vehicles has seen a steady increase during the last year (2012), although many of these vehicles are mostly for PR purposes or bought by the public sector that wants to lead by example. Still, barriers in the form of high purchase costs, an anxiety for the limited battery capacity and the lack of standardisation are some of the problems that the market is struggling to solve.

Informationskvalitet: informationssökares syn på kvalitet

The aim of this thesis is to examine how different kinds of information seekers are evaluating information quality in the information flow online. To address the problem stated, qualitative interviews were carried out with a librarian as a reference person and a group consisting of journalists and scientists. The result of the study implies that the reference person is well aware of the strategies employed by her in the search process. However, the respondents are not aware of the strategies they are actually using. An explanation is the respondents lack of education in information seeking.

Lycksabäcken, ett riksintresse med komplext deglaciationsförlopp : Presentation av ett möjligt scenario över deglaciationen i området

The area of Lycksabäcken northwest of Lycksele is a national interest of natural conservationbecause of its geological values with many unique landforms. Many of these landforms indicatethat the deglaciation process in the area was very complex. However, the deglaciation process inthe area has not previously been fully understood. The aim is to add to the knowledge of theevents that took place during the last deglaciation. To do this, the glaciofluvial landforms in thearea were mapped by studying aerial photographs with a Wild Aviopreter and a five-day fieldinventory of key areas for the interpretation.

Konsekvenser av principbaserade regelverk: En studie av säkringsredovisning på en svensk storbank

IASB is currently working with the replacement of IAS 39 Financial Instruments: Recognition and Measurement. The new standard IFRS 9 Financial Instruments is said to be based on principles as opposed to the more rules-based IAS 39. This thesis examines the third phase of the project regarding micro hedge accounting. The expressed goal from IASB is to provide more useful hedge accounting information by reducing complexity of the standard. To examine the potential effects of the transition from the rules based IAS 39 to the more principles based IFRS 9, we have performed a case study on a major Swedish bank.

Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.

A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ?til April2014.

Vingårdar i Sverige! : farligt för miljön?

The future climate of Sweden is expected to become warmer in the future. This would be beneficial for vineyards and may lead to a greater area being allocated for wine production. The environmental impact concerning eutrophication from Swedish vineyards has not been evaluated before. In this study nutrient balances are constructed for four Swedish vineyards with the goal to estimate the out and in flows of nutrient in the systems for the year 2010. Interviews with focus on farming practices undertaken during the year are conducted with the farmers.

Testikelmått och daglig spermieproduktion hos svenska halvblodshingstar :

Testicular measurements and daily sperm output (DSO) are important factors affecting reproductive capacity of stallions. In the present study testicular measurements of 10 Swedish half-blood stallions were determined (height, length, width and volume). Ejaculates were collected from each stallion once daily for 10 days to evaluate some important seminal characteristics: gel-free ejaculate volume, sperm concentration, percent progressively motile spermatozoa and total number of spermatozoa (TSN). The gel-free ejaculate volume was measured with a graduated cylinder, the sperm concentration was counted in a Bürker chamber, the sperm motility was estimated in a phase-contrast microscope and TSN was determined by multiplying the gel-free seminal volume by the sperm concentration. Testicular measurements were as follows (left and right testis): height 7,5 cm and 7,8 cm, length 10,6 cm and 10,8 cm, width 6,5 cm and 6,6 cm, volume 278,2 cm3 and 293,8 cm3, scrotal width 12,3 cm and total testicular volume 572,0 cm3 .

Biljardproblem

Objective: In recent years there has been an increasing interest within the clinical (medical) science in measuring people?s health. When estimating quality of life, present practise is to use the EQ-5D questionnaire and an index which weighs the different questions. The question is what happens if the individuals estimate there own health, would it differ from the public preferences? The aim is to make a new prediction model based on the opinion of patients and compare it to the present model based on public preferences.Method: A sample of 362 patients with unstable coronary artery disease from the Frisc II trial, valued their quality of life in the acute phase and after 3, 6 and 12 months.

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