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973 Uppsatser om Mann-Kendall tests - Sida 7 av 65
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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.
Oljetemperaturens inverkan på motoroljans degradering i lastbil
The market for heavy duty engines is constantly requiring engines that should be more andmore powerful, while still maintaining low fuel consumption. As a result of increasing enginepower, the engine and coolant temperature increases as well due to insufficient coolingperformance (because of design issues, cost etc.).Also, emission legislations, both current and future, require more and more measures to betaken by engine manufacturers. One way of meeting the legislations is the use of cooled EGR(Exhaust Gas Recirculation), which also lead to increased coolant temperatures.Both these factors also naturally lead to increased engine oil temperatures, the consequencesof which are not thoroughly investigated.This thesis project aims to investigate effects of high temperatures on engine oil degradation,with focus on the greatest degradation process: oxidation. To do this several engine runs havebeen performed on a 310 hp engine with EGR to see what happens to the engine oil in a realengine when exposed to high temperatures. During the tests oil samples have been taken andanalysed for important parameters.As a complement to these engine tests some laboratory oxidation testing have also beenperformed, to be able to compare engine test data with laboratory tests.One goal of the project was to try to formulate an empirical oxidation model, which would beable to predict oil oxidation levels in an engine, given any running parameters.
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.
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.
FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard
In the last decades, high speed cutting has become an attractive technology in the wood industry. The possibility of reducing global costs in addiction with an increase in productivity, were the main reasons for the enlargement of the use of this technology. As usual, these advantages are accompanied by disadvantages that should be carefully analyzed. If on the one hand cutting forces are reduced with increasing cutting speeds, on the other hand, the centrifugal forces affecting the tool are higher. Exposed to such high loads, there is a considerable risk of tool failure that embeds hazards for both machine and workers.
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.
Fonologiskt korttidsminne hos tvåspråkiga barn med och utan språkstörning
Repetition of Non- word (make- up word that has not some semantic content) has been proposed as a reliable index of phonological memory in children with language impairment (LI). The aim of this study was to find out the possible similarities and differences concerning phonotactic non-words and working memory in 18 bilingual Swedish-Arabic children with and without LI ages 4-6 years. The investigation was undertaken by conducting three tests including NEPSY, WPPSI-III and a Word repetition test. The results showed that there are not significant differences between the two groups regarding various parts of NEPSY. On the other hand the results showed two significant differences in WPPSI-III regarding Picture categories and Word repetition tests for Swedish Non-word.
Ytstridsfartygs ballistiska skydd mot finkalibriga projektiler
This paper is about the extent to which simplified penetration calculations ofsmall-caliber projectiles is a useful tool for assessing the physical protectioncapability. The work should be seen as an attempt to create an accessible tool inthe form of a simplified equation that allows for a better and safer use of thenaval vessels. The tool will also be used at different levels so that decisions andinstructions could be clearer.Performed calculations show a very limited capacity of a ship's basic design interms of physical protection against the use of small-caliber projectiles.How do we know that the calculations correct? By verifying the calculations withpractical shooting tests, a substantial condition to answer the question will becreated. To shoot against a material with two different thicknesses estimated toproduce perforation and non-perforation is a good approximation of the equationusability in the context..