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1087 Uppsatser om Laboratory tests - Sida 11 av 73
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This technical report describes the master thesis in material engineering called ?Testing of surfaced hardened materials conceivable for gears and shafts?. The work extents 20 academic points. Land systems Hägglunds manufactures and sells different kinds of combat vehicles and terrain vehicles. Since the demands for bigger and stronger vehicles increases all the time, so are the demands on shafts, gears and other transmission details.
Optimism och stress : En enkätundersökning om förhållandet mellan självupplevd optimism och stress
The idea with this study is to examine if there are a connection between how optimistic people are in relation to how stressed they feel. The result from the survey is based on materials from a questionnaire has been sent to fifty persons of varying age and sexes. The questionnaire has also been sent to students from Karlstad University but also to friends and acquaintances. The data is measured with SE- and LOT-tests. The issues concerned in which scope respondents experiences themselves stressed and optimistic and how the connection is between experienced stress and optimism in relation to results on the figure tests.
Noggrannhet vid målinmätning : Analys av ett eldledningsinstrument med förbättringsförslag
This Master Thesis has been conducted as an assignment of the Swedish Defence MaterialAdministration and the Swedish Armed Forces and aims to examine the Target Location Error(TLE) of a Forward Observer System. The targeting accuracy of the system is vital if the systemis to be used as a sensor for precision munitions. The analyzed system, EOI (FOI 2000), wasdelivered to the Swedish Armed Forces in 2007. The targeting sequence starts with deciding theposition of the system with a GPS-receiver, continues with methods where the north direction issettled and ends by measuring the distance, direction and elevation to the target. When allparameters have been measured the system calculates the position of the target.
Mjölkkyl till espressomaskin : Impressive cooler
The project was made in cooperation with Coffee Queen AB, Arvika. The task was to develop and design a new cooler for the milk to Jura Impressa X9, an espresso machine. The good assistance with staff at Coffee Queen and engineers in China and at KPA in Karlstad led to a solution to the problem. It was a long road to get there, many different concepts was developed. When the day came to decide which concept to work with, the choice stood between two different technical solutions.
Design av en ejektorspädare samt ett system för partikelmassmätning av dieselavgaser
This master thesis was a subtask of a project called EMIR-1. The goal with the thesis was tobuild a system for particulate mass measurements in one of the engine test cells at KTH. Theparticulate mass measurements are planned to be measured with a TEOM.The exhaust gases must first be diluted with air before the sample is sent to the TEOM.Therefore an ejector diluter for this matter also was designed and evaluated in the thesis.Emissions measurements have been done both with and without dilution to determine thedilution ratio. Tests have been done for different speeds and loads.Problems with stability of the dilution ratio have been an issue throughout the process andpressure pulsations in the exhaust pipe are believed to be the cause. More tests have to be done tomake sure that this is the problem.One idea is to make the inner diameter of the diluter nozzle smaller and see if it changes thedilution ratio stability.
Fiberföstärkning av Limträbalkar
Glulam is a product that was engineered to make use of timber in a more efficient way. Bychoosing timber of similar quality and discarding natural defects during production, thedevelopment of a stronger cross-section is achieved.Carbon fiber is a relatively new material with a high tension capacity. This feature is used toexamine how the bending capacity of the beams improve by adhering carbon fiber laminateson the lower edge of the beamsThe strength of the material is tested with three experiments: carbon fiber on the bottom of thebeam (a), carbon fiber attached to the lower sides of the beam (b) and carbon fiber in thebeam, covered with a layer of wood (c)The results show that the first case, where the carbon fiber is attached to the bottom of thebeam, gave the best result with an increase in capacity of 59 % compared to the nonreinforcedcontrol. The other two cases also show an improvement in capacity, beam-type 3had a capacity increase of 47% and beam-type 4 increased with 25 %Tests were also made with glulam beams reinforced with fiberglass, but these tests were notanalyzed in depth because the purpose was to compare the capacity to carbon fiber. Thisbeam improved its capacity by 40.3%.The tests show that carbon fiber as a reinforcement material for glulam is a good choice whenthere is a requirement for stronger cross-sections in both new production and renovation ofold buildings.
Optimism & Känsla av Sammanhang : En Jämförelse Mellan Tjänstemän och Kollektivanställda
We set out to compare two different categories of workers: the, so called, white- and blue collar workers. The studies aim was to measure if there were any observable differences between the two in means of optimism and sense of coherence. There are two tools created for measuring optimism and sense of coherence, the Life Orientation Test ? Revised (LOT-R) measures an individual?s level of optimism and Aaron Antonovsky devised a test for measuring an individual?s level of sense of coherence (SOC). Optimism is best explained like a way to measure anticipation, how an individual expect future events to fall out.
Simulering av filtrerade skärmfärger
This report present a working model for simulation of what happens to colors displayed on screens when they are observed through optical filters. The results of the model can be used to visually, on one screen, simulate another screen with an applied optical filter. The model can also produce CIE color difference values for the simulated screen colors. The model is data driven and requires spectral measurements for at least the screen to be simulated and the physical filters that will be used. The model is divided into three separate modules or steps where each of the modules can be easily replaced by alternative implementations or solutions.
Reflekterande eller reproducerande matematik : en jämförande studie mellan två undervisningsmetoder i matematik, det laborativa och det traditionella
In each classroom there is a teacher with good intentions wanting what´s best for their pupils. But grades and tests in mathematics from 2009 in Sweden shows there is a crack between the subject being taught and the learning child. The purpose with this research is to find an understanding from a teaching and learning perspective of which teaching method is more suitable for teaching and learning mathematics by doing a comparison between two methods. The main question is:What are the advantages and disadvantages of the traditional and the laboratory method of teaching, supported by the two keywords teaching method and learning?This C-paper is based on a qualitative research aiming to gather an in-depth understanding of human behavior.
Positive reinforcement training for laboratory mice
The mouse (Mus musculus) is the most commonly used mammal in biomedical research and can easily be restrained by both hand and by a device. Restraining animals causes stress that not only decreases the animal?s wellbeing, but may also influence the research results. The first aim of this study was to train mice to voluntarily stand still using positive reinforcement training. Another benefit of teaching a mouse to stand still is that you can avoid anaesthesia for some procedures.
Matematiksvårigheter : En studie om fyra pedagogers erfarenheter kring matematiksvårigheter med exempel på pedagogiskt arbetssätt
For many years, I have tried to understand why students end up in difficulties in mathematics. As a future teacher, it is extremely important to have knowledge of the various factors that leads to difficulties in mathematics. As a teacher it is obvious to meet the students who find mathematics a difficult subject, and, therefore it is necessary to have a broader knowledge of how to respond and support these students. According to Ahlberg, number of students with mathematics difficulties is increasing every year, therefore, it is important to help students and organize a supporting school environment that promotes and encourages learning (Ahlberg 2001, p. 104-105).
Exercise pens as an environmental enrichment for laboratory rabbits
This thesis analyzes the effects of different fertilization strategies on forest management at Holmen Skog in Umeå district. Harvesting volumes, net present values and fertilization intensity are presented for each fertilization scenario. The planning reserve (percentage area older than minimum final felling age) was also analyzed in this study.The thesis covers the analysis of five different fertilization scenarios, varying in fertilization intensity, from no fertilization at all, to fertilization at every harvesting operation (thinning or final felling). A sub-study was also carried out so the reader in detail can see how the different fertilization scenarios affect individual forest stands of different nature. The analysis has been done with the planning tool PlanWise, which is an application of the Heureka analysis and planning system.
Genetisk analys av data från fölbesiktning och jämförelse med resultat vid treårstest :
More than 1000 Swedish Warmblood foals are shown every year at foal inspections which are arranged around the country. Six traits are evaluated at these inspections: type, head-neck-body, correctness of legs, walk, trot and canter. No previous genetic studies have been done on the data from these evaluations. The purpose of this study was to do genetic analyses of the traits which are evaluated at foal inspections. The purpose was also to see if there are any correlations between the results of the foal inspections and the results from the tests of three-year-old horses.
Utveckling av 22 : -en motkolvs HCCI motor
Environment friendly transports are one of the main topics in the industry and society today.Shell organizes an annual university competition called Shell Eco Marathon. The goal is to buildthe car that consumes the least fuel during a race. KTH participated for the first time in 2006.The engine for this competition, DoubleTwo, has been developed within the school. Theprinciple is a two stroke counter piston HCCI engine with variable compression ratio. HCCIstands for homogenous charge compression ignition.
Störst, Bäst och Vackrast: En studie av varumärkessaliens påverkan på attityder och attributvärdering
The authors study the effects of brand salience on how consumers form brand attitudes and how consumers value the importance of various brand attributes. The study was conducted through two separate tests, the one focusing on the link between brand salience and brand attitudes and the other focusing on the link between brand salience and evaluations of attribute importance. Both tests measured brand salience as the ease with which brands are recalled by respondents who have been cued with a specific product category. The results show that brand salience has direct effects on both brand attitudes and the evaluation of attribute importance. As brands are recalled, high brand salience for a brand creates a more positive attitude towards that brand in the mind of the consumer.