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324 Uppsatser om Experiments - Sida 1 av 22

En komparativ litteraturstudie av olika termkällor för query expansion

The purpose of this thesis is to make a comparative literary study of ten laboratory Experiments with different kind of sources for query expansion terms. The Experiments are grouped according to categories of term sources, which are: search results, collection dependent knowledge structures, collection independent knowledge structures and one that combines the two last mentioned sources into one. To enable a comparison all other variables were held as constant as possible. There is the improvement measured in mean average precision, which is used to measure the various sources potential. The result from the study shows a strong connection between the kind of source for the expansion term and improvement of the result.

Undersökning av titanföreningar för tillverkning av standarder vid användning av röntgenfluorescens

SECO Tools manufactures tool inserts for all types of metal cutting machining. (Ti,W)C is a common raw material used in the production. At arrival, the material (Ti,W)C is always analyzed. Titanium has previously been analysed with x-ray fluorescence spectrometry, but as the calibration has previously been performed with two different types of titanium (rutile and metallic titanium), the results has differed. Because of that, this thesis project has been devoted to analyze titanium, to find the best titanium compound for producing standards.The work has been performed using literature studies and many Experiments in the laboratories at SECO Tools inFagersta,Sweden.

Kommunikation i multiagentsystem

Communication is an important part of any multi-agent system. There are different ways of communicating and they have different effects on a multi-agent system. This project describes and evaluates two different ways of communication, implicit and explicit. To compare the two methods, two Experiments have been executed. The result of the Experiments have been compared and discussed.

Fällning av kisel från avloppsvatten vid Hellisheidarvirkjun - experimentell studie

This report is about the Experiments with mixing of the separated water and the vacuum pump seal water at Hellisheiði power plant. This is done to prevent silica scaling and clogging in pipes and reinjection wells as well as eliminating vacuum pump seal water from the plant. The Experiments were done in four stages: the first stage comprised of tests with different flows of separated water at 70°C, the second stage was carried out by mixing the separated water at 70°C and the seal water with different amounts of the seal water, the third and the fourth stages were like the first and second but with the separated water at 120°C. The results show that this method is good if the mixture is around 50/50 separated water and seal water, to control the silica scaling in the separated water and to be able to reinject the seal water with the separated water. This does not eliminate the silica scaling in all of the separated water because the amount of separated water is much more than the amount of seal water that comes from the plant. .

Textil och glas ? ett universum

This work is about presenting the weave in a new and different context, by bringing textile and glass together. The work is characterized by material and shape Experiments with silver and copper weave and hand blown glass. From Experiments and sketches, the work has resulted in four sculptures, symbolizing four selected stages in a lifecycle; the birth, the development, the maturity and the death. One important part of the work has been to combine different materials and techniques.Studies of literature, sketching, handweaving and integration of silver and copper weave in the glass have been important methods in the working process. Inspired by the flower, the human being and the universe, a story about the life cycle has taken shape.The paper describes the working process with choices and analyses.

Undersökning av steady state och utvärdering av valskraft och friktion vid kallvalsning av aluminium

The purpose with this thesis was to examine the cold rolling mill located at Högskolan Dalarna and to stabilize the rolling process, to achieve steady state. Experiments with cold rolling of an aluminium strip have given results for rolling force, friction, reduction, strip tension and strain hardening. Results show that steady state has been found for the Experiments with roll force and strain hardening, and not been found for the Experiments with friction and reduction. Results show that increased strip tension gives lower roll forces. The roll force equation of Stone shows comparable results with reality for dry contact with reductions up to 30 %, but starts being incomparable with higher reductions.

Startfosfor till höstvete :

There is always an endeavor to govern the initial products in the plant cultivation with precision in order to keep down the expenditure and in order to decrease environmental impact. Initial phosphorus fertilizer can then be one possibility in order to keep down the fertilizer cost and to decrease environmental impact. This exam study includes a literature study about location of fertilizer and which effects this give and two field Experiments. The aim with initial phosphorus fertilizer to autumn wheat is to accelerate the root growth and to give the crop a big root system before the growth stagnates before the winter. Easy to access phosphorus favours the root growth.

Valsningsteknik för extremt höghållfasta tunna stål

New high strength steels require improved cold rolling techniques. The aim of this degree project was to develop a new and money saving cold rolling technique to manufacture steel strip for saw blades. The work is based on earlier rolling Experiments made with a high carbon steel grade at LuCoil Steel AB. The work also focused on the mill requirements to cold roll high strength steels. The results show that LuCoil?s existing cold rolling mill was actually designed for rolling low carbon steel.

Gjutfel och dålig ornamentik - Om bronsgjutares hantverksskicklighet under skandinavisk bronsålder.

The purpose of this essay is to investigate whether bronze workers during the Bronze Age were exclusively specialized, or there actually existed amateur craftsmen. Through archaeological Experiments and artefact studies I intend to investigate if it has been at all possible for a less experienced bronze caster to produce usable objects. The purpose is also to investigate and put to the test the casting methods used during the Bronze Age in an attempt to find out which steps of the craft are the difficult and crucial ones, and try to determine if it has been possible to manufacture bronze objects on an industrial level..

Kommunikation i multiagentsystem

Communication is an important part of any multi-agent system. There are different ways of communicating and they have different effects on a multi-agent system. This project describes and evaluates two different ways of communication, implicit and explicit. To compare the two methods, two Experiments have been executed. The result of the Experiments have been compared and discussed.

Filter och kapsling för IR-givare

This paper describes the work done trying to diminish the noise present in the signal from an IR-detector. The project was aiming towards two different kinds of applications; heat protection and presence detection. The hypothesis was that the signal-noise ratio would decrease if a filter and a proper installation were used for the detector. Some Experiments were executed to determine what kind of filter were the most suitable for each application and how these could be installed. After executing the Experiments and evaluate the results we recommend to use a specific filter for each application.

Bestämning av lägsta luminans för utrymningsskyltar

This report is based upon an experimental study of exit sign luminescence in different environments. The purpose is to evaluate the lowest luminescence of an exit sign, based upon Swedish regulations. Scientific Experiments have been conducted in a controlled environment, where exit sign luminescence was graded by an evaluation group. The results of these have been verified by similar Experiments that took place in two department stores. The final result of the study is guidelines for appropriate exit sign luminescence in different environments..

Den rätta känlslan : Om den grafiska formgivarens nödvändighet  och förhållande till prosatext

The right touch is a project investigating the necessity of the graphic designer in relation to prose text.The project is partly theoretical and partly practical. A series of interviews with graphic designers, publishers and writers has been conducted to discuss the relationship between content and form in prose. In addition to these interviews, I have done theoretical research on the historical, political and economical context of the designed prose. Based on the findings during the theoretical research, a series of practical Experiments was also executed. This project has had several outcomes but one of the more noteworthy is two methods for challenging the references in the act of designing prose (choosing a typeface, for example) using algorithms.

Inverkan av Kiselhalten på Värmeutvidgningskoefficienten hos Aluminiumlegeringar

The purpose of this report is to document the Experiments carried out, methods used and results gained during research into how the silicon content of an aluminium alloy affects the coefficient of thermal expansion (CTE).The goal of this paper is to better understand and to find a relation between silicon content and the coefficient of thermal expansion.Experiments were carried out using carefully prepared samples of Al Si alloys (0, 7, 10 and 20% Si content). Using these alloys, the CTE could be measured using a dilatometer.Comparative analysis carried out could map the effects of silicon content on the coefficient of thermal expansion and an equation was created. Using simple graphs and the rule of mixture method, the authors were able to build a simple tool for calculating the CTE of specific aluminum silicon alloys..

Dexametasons effekt på trombocytaggregering och syreradikalproduktion

Platelets are important for the healing of damaged blood vessels since they have an importantpart to play in the coagulation process. At the same time, the blood must be kept fluid and notcoagulate at the wrong time. Therefore there are factors that effect the aggregation of plateletsin a positive or a negative way.Previous investigations have shown that platelets during stirring conditions produce reactiveoxygen species (ROS) that weaken the inhibiting effect of nitric oxides (NO) on platelets andthat the drug Dexamethasone (Dex) can reduce the ROS-production.The aim of this project was to investigate if glucocorticoids, in this case Dexamethasone,could restore the inhibiting effect of NO on platelets and if there was any decrease in ROS-production.The result of the ROS-measurements showed a great variance and it was difficult to draw anyconclusions from them, but a clear decrease in ROS, as previous reported, was not shown. In the aggregation Experiments the inhibiting effect of NO was observed through the drug S-nitroso-N-acetylpenicillamine (SNAP), a NO-donator.From the aggregation Experiments, the result seemed to be that SNAP during longerincubation time lost its inhibiting effect, probably because the cells become desensitized.With superoxid dismutase (SOD), the effect of SNAP increased, both in the experiment withlonger and shorter incubation times. Dex seemed to reinforce the aggregation in relation toboth SOD and SNAP.

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