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196 Uppsatser om Accuracy - Sida 4 av 14
En undersökning av framtidametoder för att säkra förband i produktion
The thesis is an examination of the methods that are appropriate and long-term choice to obtain clamping force and secure screw joints in production. The employer, Scania CV AB, transmission manufactures axle gears to all trucks produced in Södertälje. One of the most common assembly elements is screw joints, where the clamping force is essential to achieve a secure joint. Current methods to secure the joint is due much of the friction effect and is an indirect method to measure the clamping force. The clampforce Accuracy becomes more widely with torque angle control.
Automatisk genreklassifikation : en experimentell studie
This thesis aims at examining to what extent a few, algorithmically very easily extractable document features can be used to classify electronic documents according to genre. A set of experiments is therefore carried out, using only 11 such simple features in an attempt to classify 84 documents belonging to electronic academic journals into three manually identified genres: table of contents, article, and review. The 11 features are also divided into three sets, containing metrics of words and sentences; punctuation marks; and URL links, respectively. The performance when using these sets of features is then measured with regard to classification Accuracy, using a k-NN classifier, four different values of k (1, 3, 5, 7), and both leave-one-out and 10-fold cross-validation. Best results are achieved when using all three feature sets (i.e.
Reglerstrategi för fria ventiler : ? Utveckling av en fyrtakts förbränningsmodell för att prediktera optimala ventilinställningar
As emission legislations across the world continuously pushes engine development forward,engineers constantly need to come up with and implement fuel saving technologies. During thelast decade, variable cam phasing has become a popular solution to increase gas exchangeefficiency. This configuration is typically mechanically constrained by camshaft limitations, anda solution to circumvent this problem would be to use a different valve actuation principle.One example of this is to use pressurized air controlled by electrical solenoids. Such a systemhas been developed byCargine Engineering and this provides the starting point for this work. Tobe able to operate the valvetrain on an actual engine, a control system is needed.
Regressionsmodellering av dynamiska råemissioner från statiska mätningar
By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good Accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodAccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.
Fältmätningar av limträbalkars elasticitetsmoduler : utvärdering av tre mätmetoder
This study investigates three different methods for evaluating MOE,Modulus of Elasticity, in field measurements. The purpose is toinvestigate the possibility to use dynamic measurement methods infield measurements that hitherto (2010) has been performed with staticmethods. The objects of investigation are 20 glulam beams. The firstfield measurement took place in november 2007 and applied a staticmethod based on the standard SS-EN 408. The second measurement,described in this study, took place during summer 2010, and appliedstatic as well as dynamic methods.The MOE of wood is affected by a range different factors.
Prevalence of congenital defects in Swedish Hampshire, Landrace and Yorkshire pig breeds and opinions on their prevalence in Swedish commercial herds
This study concerns congenital defects in pigs; umbilical and scrotal hernia, cryptorchidism, kyphosis, splay legs, anal atresia, intersexuality and congenital tremor. The aim was to describe and estimate the prevalence of these defects and estimate the heritability for the most frequent defects, scrotal hernia and cryptorchidism in purebred Swedish Hampshire, Landrace and Yorkshire populations. Furthermore, information and opinions from herdsmen in commercial herds was collected and analysed. A low proportion of congenital defect pigs is of importance both from animal welfare and economic point of view. The Accuracy of registration of the presence of defects in the litters has a decisive role for the ability to select against these defects.
Mean value modelling of a poppet valve EGR-system
Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.
Ligger bäckarna rätt i kartan?
?Are the headwaters streams at the right position in the map? is a study that has been performed on behalf of Holmen Forest, region Örnsköldsvik. This study will be the basis for deciding if the Hydrology Layer Property map or Holmen Forest map will be used for planning nitrogen fertilization in forestry. The background to this study is that nitrogen fertilization near water will increase the risk of nitrogen leaching out into the water systems, which has a negative impact on the environment. The headstreams positions have been recorded in the field with a GPS and the data analyzed in the geographic information system ArcMap.
MeasureApp : Utveckling av en Android-applikation fo?r ma?tning och kartvisning med hja?lp av GPS
The objective of this project was to develop an application for mobile phones using the Android operating system. The main goal was, with the help of GPS, to pinpoint locations, measure distance traveled and illustrate the progress on a map. Functionalities for just showing the map, fetching addresses and saving to a database was also implemented. The result of the work was a proper application, called MeasureApp, that fulfills the goals set in the planning stages of the project. MeasureApp can be used to measure distances where Accuracy is not a main factor, i.e walks or runs.
Två metoder av finutsättning och dess noggrannheter
This report describes a study of two different methods to achive the best possible result in setting out apartment details. These two methods are the setting out of details with a measuring tape from baselines and the setting out procedure with an instrument (totalstation).Through our knowledge in surveying and mapping technology and help from a carpenter, this investigation has been implemented. The setting out using a tape has been performed by letting the carpenter to set out windows, bathroom and water- and drain-details from baselines and drawing. The setting out using a surveying instrument was carried out by means of a Trimble Total Station. These two methods have been compared in order to detect and show the difference that occurs.The report shows the investigation background story from the practice of Swedish Mätcenter in Karlstad.A result of differences in Accuracy and time is described in the report, as well as their theoretical consequences.
Utveckling av applikation för android-plattformen : Förenklad medicinering genom ny teknik
The objective of this project was to develop an application for mobile phones using the Android operating system. The main goal was, with the help of GPS, to pinpoint locations, measure distance traveled and illustrate the progress on a map. Functionalities for just showing the map, fetching addresses and saving to a database was also implemented. The result of the work was a proper application, called MeasureApp, that fulfills the goals set in the planning stages of the project. MeasureApp can be used to measure distances where Accuracy is not a main factor, i.e walks or runs.
Visuellt jämföra filmtrailers med hjälp av matlab
The primary intention of this paper was to visually compare film trailers without considering semantic information, through use of a self-developed Matlab program, resembling that of human perception. Circa 150 people participated in an online survey where they were shown two film trailers and asked to rate their visual similarities. The result from the program was weighted against the survey results in such a way that the weights corresponded to a 75% Accuracy between the program?s and the participant?s (for participants with prior experience in the field of photography and/or film) comparisons.How accurate can we compare still images from film trailers, and find similar trailers for the human viewer, by analyzing saturation, color tone, contrast and lightness with a self-developed Matlab program..
Introduktion av Open Source som arbetssätt
In early January 2010 the authors participated in a meeting with the chief engineer for a company in which a central part is manufacturing of printed circuit boards (PCB). At this meeting it emerged that the machinery and production methods have changed substantially since the early 1990's. The spreadsheet for preliminary production time calculations by the company is today based on conditions from almost 20 years ago. The company has over the years been trying to adjust the spreadsheet template. The result of these adjustments has filled it with historical residue, something which makes the template difficult and time consuming when the primary user tries to handle it.The purpose of this study was to help the company increase its Accuracy in the representation of the production times for the different PCB-based products by developing a new costing model based on an already existing but inadequate spreadsheet template. The company also expressed the wish that the new costing model would be less time consuming to work with.The methods used to achieve the goal are interviewing, participatory observations and meetings with relevant persons. The data obtained were analyzed using the theory on PCB production and visualization of data.
Kommunikation med drivlina : Implementering av seriell kommunikation och LabView-gra?nssnitt fo?r DSPer i drivlina
The objective of this project was to develop an application for mobile phones using the Android operating system. The main goal was, with the help of GPS, to pinpoint locations, measure distance traveled and illustrate the progress on a map. Functionalities for just showing the map, fetching addresses and saving to a database was also implemented. The result of the work was a proper application, called MeasureApp, that fulfills the goals set in the planning stages of the project. MeasureApp can be used to measure distances where Accuracy is not a main factor, i.e walks or runs.
Prognostisering av räntabilitet på eget kapital - En jämförelsestudie av tre regressionsmodellers prognosförmåga applicerat på svenska data
A multivariate cross-sectional model is used in this thesis to proxy for expected earnings and to estimate return on equity for 214 companies over the period 2009-2013, using Swedish data. The model, which has never been tested on Swedish data before, is first confirmed to function as a forecasting model for expected return. Furthermore, the model is evaluated through a comparison with two univariate models based on the assumption that return on equity follows a mean reversion process. Forecast Accuracy is calculated as the difference of estimated returns and actual returns. The results show that the univariate models' forecasts are superior to the multivariate model's..