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8533 Uppsatser om Hypothetico-deductive method - Sida 19 av 569
Metodik för utmattningsberäkning av svets i vibrationsmiljö
In this work, a method was developed and evaluated for calculating the life of welds under the influence of fatigue loads from a vibration environment. Typically, a shaker table is used for testing a component against vibration loads. The shaker table creates a vibration environment that is defined in the frequency domain by a power spectrum.Similarly, a virtual vibration table can be used to calculate the same type of load environment, which can then be used to calculate the expected lifetime. The benefit of this method is that it can be used in design, as well as in simulation of tests before physical verification tests are carried out.Today there are methods for calculating fatigue life of non-welded base material, but since many components contain welded joints, there is a need to apply this method to those types as well. To achieve this, the thesis combines two different areas, which together provide a method for fatigue assessment of welds using a virtual shaker table.The methodology is carried out by modeling the component, and its welded joints, in a finite element program.
Statusbedömning av asynkronmotorer
Induction motors, often referred to as the workhorse of the industry, play an important role in production today. Therefore, it's important to diagnose any faulty induction motor prior to failure to avoid costly and time consuming production stops.This thesis compares methods for diagnosing induction motors in operation, MCSA, Park's vector approach and the standard method used by Swedish industries today. By simulating broken rotor bars and short-circuit in one of the windings, each method is tested and the results are compared using matlab.The results need further verification due to uncertainties of the condition of the test motor, even though the experiment gives a hint of the different advantages of each method. A combination of the methods should be able to tell if the motor needs further examination..
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.
Jämförelse mellan MultiScat och konventionell beräkning av intensiteter till koncentrationer vid analys med röntgenflourescensspektrometri
In this master thesis work, a new method called MultiScat, is compared with the conventional method with alfa-correction, for computing concentrations from intensities in X-ray spectrometric analysis. The conventional model is a linear model, which only takes the photoelectric effect into consideration. It doesn't consider Rayleigh and Compton scattering even though it has a great impact on the measured intensities. Here MultiScat differs a lot. MultiScat is based on a solution of the Boltzmann transport equation.
A comparison of methods to assess site index in young Norway spruce stands
This study investigates whether the site index curve method (SICM) and the growth intercept method (GIM) can be used for site index predictions in younger Norway spruce (Picea abies (L.) Karst.) stands than recommended by current guidelines. For SICM it was thus investigated whether the method could be used for stands younger than ten years, and for GIM it was tested whether a starting point for the intercept measurements could be used below the recommended
2.5 meter. This was tested based on measurements taken from experimental stands in Tönnersjöheden Research Forest.
For GIM it was found that the method can only be used when the TH-trees of a stand have five complete intercepts above 2.5 meters. For the method to be applicable beyond this, it will be necessary to adapt the underlying equations, perhaps following the Canadian example where a 1.3 meter intercept start is used. In conclusion it is not currently possible to apply the approach beyond the current recommendations.
For SICM, SI predictions are accurate for the study area already form year three.
Estimering av GPS pålitlighet och GPS/INS fusion
The global Positioning System (GPS) provides location and time information as long as there are unobstructed lines of sight to four or more GPS satellites. However, when this is not the case the signal may be inaccurate or sometimes even completely blocked. In these situations the Inertial Navigation System (INS) is an appropriate choice for positioning. An INS has already been proposed in a previous thesis by Erik Andersson and the objective of this thesis is to fuse the GPS with the INS in a proper way. A part of this project is to decide the reliability of the GPS.Three methods for GPS reliability detection have been proposed. One method based on the statistical properties of each of the separate systems, and two methods based on the statistical properties of the residuals between the GPS and INS.
Utveckling av metoder att mäta centrering av skruvhål i skär
There have been, in some rare cases, difficulties with clamping of inserts with U-holesin their tool holder. According to the complaints, the inserts could not be properlyclamped or could fracture when clamped. A study has shown that variations inclamping behaviour are mainly depending by the position of the screw hole in the toolholder and the centering of the screw hole in the insert.The focus of this project has been the centering of screw hole in insert. It has beenshown that the screw holes are not always enough centered in the insert. Theproblem may occur after a certain step in the production, i.e.
Effektiv ordinlärning? : En studie av aktiv ordinlärning i engelska inom gymnasieskolan
The purpose of this essay is to discuss and compare different ways of learning new words and expanding your vocabulary in a foreign language. This is done by an examination of relevant literature and available research, as well as by an empirical study with two upper secondary school classes, in which two different methods are put to the test: one traditional method of the kind that is found to be most common in second language acquisition, and one designed to take existing research into account. The results show that, although effective in the initial stages of acquisition, the traditional method, where words are learned in isolation and via translation to L1, results in a very limited form of knowledge. A big part of the words acquired via this method is also forgotten soon afterwards. The other method, where words were learned and tested in its proper context, was found to result in a broader form of vocabulary knowledge, covering more aspects, and that remained over time.
ELever möter Lagerlöf : en responsstudie av gymnasieelevers första möte med en text
This study examines the way Swedish students in Upper Secondary School respond to two excerpts from a classic Swedish novel. The paper?s aim is both to give an overview over some of the theoretical concepts concerning the field of reader-response criticism, and to describe and analyse what the students experience in their first meeting with an older text. The background to my interest is the many studies showing that young readers regard reading of fiction in school as boring. By using the method of written reading responses I want to contribute to a deeper understanding of how an older text can be received, understood and engage its readers.
Sjuksköterskans arbete med Manchestertriage : arbetstillfredsställelse och kompetens
Background: Triage is the sorting of patients according to the severity of medical assessment. Triage has a long history of use in Anglo-Saxon countries but is a fairly new method in Sweden. Researchers have described the Manchester triage group method (MTS) and a literature review of the concept; working contentment and competence focusing on triage. Aim: The ambition with this study was to describe a number of triage nurses working conditions. The research questions were; working with MTS- does it bring work contentment? What kind of competence is needed? Method: Data was collected from 74 triage nurses by a questionnaire containing 37 questions and two questions provided the nurses the opportunities to describe their triage experiences.
Voltage Sags Indices and Statistics
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Ayatollah Khomeini : I ljuset av imam Alis esoteriska läror om rättvisa och politisk makt, i Nahjul Balagha
The gathered texts and letters from Ali Ibn Abi Talib, found in the book Nahjul Balagha,constitute one of the most important writings of Shiite Islam, next the hadits and the Quran.Imam Ali´s ethics and moral approach in Nahjul Balagha, is considered by imam Ali, to beseen as a guideline for both individual purposes as for any kind of governance. The esotericteachings, about truth and justice in Nahjul Balagha, should therefore probably have been of agreat concern to Ayatollah Khomeini and the Islamic revolution.This essay will from an deductive approach, on a relatively contemporary historic event, try toanalyze Ayatollah Ruhollah Khomeini´s interpreting on imam Ali´s texts and preaching inNahjul Balagha. The Islamic revolution, as the Islamic Republic of Iran, led by AyatollahKhomeini, was confirmed as both brutal and violent. My ambition in this essay, will there forconcern a possible interpreting on justice and political rule, from Ayatollah Khomeini and theIslamic Republic of Iran, on imam Ali´s teachings in Nahjul Balagha..
Kamratbedömning i svenska : Nio lärares tankar och erfarenheter
This paper studies how peer assessment is used as a strategy to improve young learners' results in Swedish as a school subject. Nine teachers are interviewed about their use of the method on 7-12-year-old pupils. Comparisons are made between the interviews and Swedish and international discussion on peer assessment. There are similarities between the practice of the teachers and what is said in the litterature about the method and its advantages and drawbacks. The teachers tend to emphasize the social aspects more, though.
Förskolechefens beslut- att välja inskolningsmetod
I have written an experiential essay about my role as a preschool director and the important work decisions that I face. What is best for the child? That is something that I think is important to take into consideration.In the narrative, I describe how an induction occurs at my preschool. We use an "old" tried and true method which spans two to three weeks, which I believe is best for children under the age of two. They need to first connect withone educator who they are comfortable with before they are secure enough to play and explore the environment of the preschool.In recent years, another method has emerged which is shorter and which has quickly became popular in many preschools.
Hur har det svenska handelsmönstret påverkats av ett medlemskap i EU?
Very often the interesting variables are explained by several underlying variables and in statistical analyses it is common to study the relationship between variables and groups of variables. Because of this multivariate analysis is commonly used in both science and industry. There are two problem with both univariate and multivariate analyses. One is when the variables are correlated. The other is when the number variables of exceeds the number of observations which makes the matrices algebra used in the analysis impossible to execute.