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15 Uppsatser om Mixer - Sida 1 av 1

Förrotation till omrörare

The primary function of a Mixer is to keep a fluid in constant motion. All mixing applicationsrequire varying degrees of small-scale turbulence and bulk flow. The performance of asubmersible Mixer is measured by the thrust that it produces, while the strength of the bulkflow is dependent on the total amount of installed thrust.In a Mixer, the fluid quickly flows past the propeller, and as a result, the current is mainlyaxial. The fluid will also obtain a rotating velocity, or a swirl, though this is significantly lessthan that of the propeller. During the process, the total amount of energy increases in the formof static pressure and kinetic energy.

Design of a Direct-conversion Radio Receiver Front-end in CMOS Technology

In this Master's thesis, a direct-conversion receiver front-end has been designed in a 0.18um CMOS technology. Direct-conversion receivers (DCR) have obvious advantages over the heterodyne counterpart. Since the intermediate frequency (IF) is zero, the problem of image is circumvented. As a result, no front-end image reject filter is required and the channel selection requires only a low-pass filter, which makes it easy to integrate directly on chip. However, the DCR also suffers from several drawbacks such as extreme sensitivity to DC offsets, 1/f noise, local oscillator (LO) leakage/radiation, front-end nonlinearity and I/Q mismatch.

Tidsstudie - grovfoderhantering :

Since feeding fodder crops to dairy cows is a heavy and time-consuming but often disregarded line of work, this study wishes to view the different possibilities that are currently available to decrease the time to feed and apply this knowledge on an existing farm. For this purpose, four farms have been studied due to what feeding systems that are currently used and how long time the feeding required. The occurring systems are either mobile, i.e. a feed Mixer operated by a tractor witch feeds the cattle via a drivable fodder table, or a stationery Mixer, i.e. an electrically powered Mixer which fills an automatic feeder.

Fyrkanaligt surroundljud med två eller tre mikrofoner

Syftet med denna empiriska studie var att undersöka, utveckla samt verifiera matris/Mixer till en prototyp för 4.0 surroundljud med två alternativt tre kondensatormikrofoner. För att undersöka detta har en Mixer/matris konstruerats och byggts. För att verifiera Mixern/matrisen har ett blindtest utförts. Resultatet av undersökningen visade att metoden fungerar med tre mikrofoner, däremot inte med två mikrofoner..

Metodik för identifiering av T-stycke med risk för termisk utmattning

Thermal fatigue is a serious problem in todays power plants. A large amount of damages around the world circles around that subject. The damage can come from the mechanism of two flows mixing with different temperatures in a T-junction. It is a fundamental prerequisite that these T-junctions are frequently tested for damages. An amount of criterias steers the rate of testings.

Tidsåtgång i system med självgående/självlastande fullfoderblandare :

In this study I have compared two systems of handling TMR, self-propelled/ self loading Mixers and conventional towed Mixers, what has been investigated is the time for filling, mixing and feeding TMR as well as maintenance and fuel consumption. The background of this study is the structural rationalization within the Swedish milk production that has put focus on efficiency and reducing of costs. Forage and labour are the two biggest costs in milk production today. The study has been performed by visiting three farms and with a stopwatch measured the times for filling, mixing and feeding TMR. At the time for the visits, the users have been interviewed regarding maintenance and fuel consumption. They have also had an opportunity to give comments of how they experience the Mixers. The result of the study after processing is that the average stock in the study can save 74000 SEK a year by reducing time for filling, mixing and feeding TMR to cows with a self propelled/ self loading Mixer . The conclusion I can make of this study is that it?s not the size of the stock that decides whether it?s interesting to invest in a self propelled/ self loading Mixer, but the presumptions on the farms, for instance forage logistics and mechanical equipment..

Implementering av lean i ett gjuteri med låga volymer och hög variation

Valmets own foundry in Karlstad has during a long period of time had problems being profitable. The goal today is to turn this around. Today there are three different productionlines; engine blocks, Yankeecylinders and components for the wind turbine industry. This master thesis has focused on examining if value stream mapping is a useful tool to use in a foundry, and therefore outside the typical manufacturing industry. The target has also been to evaluate if there is a possibility to improve the flow in the foundry and also the results.During the 20 weeks this work has been done at the foundry data has been collected and analyzed.

Analys av massapumps- och mixerarbete vid Metsä Board Sverige AB, Husums Fabriker : Energibesparingsåtgärder vid blekeri 4 & 5 med jämförelse mot ny utrustning

Husums plant has a selection of different pulp pumps at bleaching plant 4 and 5. The displacement- (HC-pump, Sund Defibrator PTD-60) and centrifugalpumps (MC-pump, MCA 42-200, MCP 30/20) are of interest in this report. The centrifugal pumps are controlled by throttle valves, which result in an energy loss. Chemical Mixers are used to mix ClO2 into the pulp before proceeding into a holding tower where the bleaching process occurs.The energy demand of the different positions has been measured or calculated to be used in comparisons against new equipment. Quotations were requested and delivered from Valmet and Sulzer.

Automatisk mikrofonmixer

Denna rapport presenterar ett examensarbete som handlar om en konceptstudie för en monteringscell. Examensarbetet har genomförts av Oskar Edström, student inom maskinteknik på Umeå Universitet, under våren 2013.Syftet med arbetet har varit att utveckla en lösning för hur en bussning, som används i Volvos lastvagnar, skall monteras ihop automatiskt i en produktionscell. Arbetet har genomförts i samarbete med uppdragsgivaren HT-Svarv i KalixFör att definiera befintliga problem med dagens konstruktion har förstudier, med kartläggning av företagets behov, genomförts. HT-Svarv vill ändra hur bussningen monteras ihop. Detta för att få kortare operationstid under processen och minska behovet av personal vid montering.

Inte ett leende före höstlovet : En kvalitativ textanalys av lärarens ledarskap sett genom fem läroplaner med auktoritetsperspektiv

This is a qualitative textual analysis of curriculum for primary education in 1962, the curriculum for primary education in 1969, the curriculum for primary education in 1980, the curriculum for the compulsory school system in 1994 and the curriculum for primary school 2011th. Purpose of this thesis is to see how the government through the curriculum specifies directives for how teachers should be more or less authoritative. The boundaries of the essay are to only look at the claims against the teacher in elementary school. The questions are what is required of the teacher directly or indirectly from the curriculum 1962,1969,1980,1994 and 2011, focusing on the concept of authority and what change has taken place? To answer these questions, I have read the current curricula and other research publications in the field.

Byggkostnader inom mjölkproduktionen - jämförelse av olika stallstorlekar och byggnadstekniska utföranden

Investment costs for eight different type housing systems for dairy cows has been calculated in order to compare the building costs as a function of herd size, shelter type and automatization. A commercial calculation programme for building was used and complemented with prices of equipments specific for dairy cow building. Herd sizes were 120, 250 and 400 cows. The milking equipments were automatic milking system (AMS), parallel parlour with 32 stalls (2x16) and rotary parlour with 24 stalls. Shelter was either insulated equipped with automatic cable driven scrapers on solid alleys, automatic feed wagon on rails, or uninsulated with manual manure handling and a tractor driven mobile Mixer wagon on a drive-through feeding table. Building cost per cow or per kg milk was calculated using an average life time and 6 % interest rate and annual milk yield is 9 500 kg/cow and year. Structure effect 3-4 % higher for an insulated structure than in an uninsulated for 400 and 120 herd respectively. This is much lower compared to what is normally argued.

Svinnoptimering VTIS1

The goals of this Bachelors? Thesis were to establish the production loss through the VTIS1 Pasteur at Arla Foods Linköping dairy and then suggest simple but effective solutions to minimize the losses for each production run. If the timeframe allowed it, some of the solutions would be implemented and tested in full production to determine their impact on economic and environmental savings.The very first step of this project was to establish the statistics over what losses there is in the production pipeline through VTIS1, from milk and powders in Mixer tanks to finished and packed products in cold storage. Then, when knowing how much product was actually lost and where, those bottlenecks could be pinpointed and examined more closely. At this stage the focus was switched, from the otherwise complicated and broad manufacturing process, to the VTIS1-aggregate, since early data indicated there were quite substantial losses there.In conjunction with this project Arla Foods purchased an absorption photometer-measuring device (OPTEK AS16) that could be inserted straight into the product stream out of VTIS1, allowing real time measurements of its optical density.

Fullfoder för får :

During recent years the use of TMR (total mixed rations) has increased in Swedish lamb production. For many years TMR has been used for cattle and hence the information and knowledge is vast, while the knowledge concerning sheep and TMR is more limited. The aim of this thesis is to present an overview of the scientific knowledge on the subject, and also to compile practical experience from sheep farmers using TMR. The thesis begins with a literature review where different aspects relevant to the usage of TMR are dealt with. It is concluded that there are differences between sheep and cattle that must be taken into account.

Salmonella prevalence in the poultry feed industry in Pakistan

Abstract One of the leading causes of food borne infections in the world is due to Salmonella by con-suming poultry products including eggs and meat. According to US Food and Drug Admin-istration (2009), 2 to 4 million cases of Salmonellosis in humans occur every year only in US. Salmonella causes wide range of diseases with enteric and typhoid fever, food poisoning, di-arrhea and gastro-enteritis. Many serotypes of Salmonella do not have host specificity and cause disease in all kinds of animals and humans. Salmonella has capability to modify accord-ing to the changing environment and it can develop resistance against routine elimination practices of sanitation, chemical treatments and antibacterial drugs. Newly established poultry industries in Pakistan are confronting various infectious diseases including Salmonellosis while in Sweden Salmonella prevalence in animal products con-sumed for humans is extremely low.

Metodutveckling för analys av PBDE och HBCD i sediment

Brominated flame retardants (BFRs) has for many years been used in products to reduce their flammability, mainly in electronic products, textiles and construction materials. In 2003, Sweden imported 300 tons of brominated flame retardants. Leakage of these compounds has polluted natural environments. Fishes has shown increased contents of these substances, especially fat fish, since brominated flame retardants tends to accumulate in fatty tissues. They are also regarded as persistent and that gives them the ability to travel long distances. What also is really scary is that increased levels of brominated flame retardants have been detected in human breast milk. The knowledge of the brominated flame retardants is limited and not so much research has been done in this field. There are many reasons though, to keep the research going. Partly their structural resemblance to well-known toxics as PCB, but also their ability to accumulate in biological systems and enrich in food chains. In which way they affect humans we really don?t know yet.