Process water is used for cooling and for transporting material in all kinds of industries. To clean the water for reuse, various types of filters can be used. Many conventional process water treatment plants incorporate sand filters, which readily clean the water from suspended matters. However, at some circumstances the sand filters do not remove high enough concentrations of metals. This master thesis compares the water treatment abilities of activated cork, produced by Spikes & Cogs AB, to those of the sand filters used at steel making company Ovako Hofors AB in Hofors. As an on-site pilot study, the thesis investigates the cleaning capacity of three types of activated cork filters: Fats, Oils and Solvents (FOSS) filter, Fast Acting Digesting Enzymes (FADE) filter, and Metal Adsorption and Concentration (MAAC) filter. The cork filters were compared to the sand filters during normal operation and, because of previous problems with the stability of the sand filter performance, during stress tests. The results show that the cleaning capacity of the sand filters is higher than the cleaning capacity of the cork filters at normal operation. At the conditions of the stress tests, at which the sand filters do not function, the cleaning capacity of the cork filters was somewhat lowered but was still well within acceptable limits. An important result from the experiments is that the cork filters neutralize the pH. The sand filters are sensitive to changes in the pH, meaning that the cork filters could function as a buffering unit prior to the sand filters.

The objectives of this study were to examine: (1) the effects of instructional and motivational self-talk verbalized overtly or covertly on self-efficacy and performance in elite golf players; and (2) the preference of motivational and instructional self-talk and how this relates to performance in elite golf players. Participants were 30 elite golf-players, with a mean age of 17.38 (± 0.94) years. A mixed model repeated measures design was implemented. The self-talk overtness manipulation failed in the overt self-talk group, and baseline differences between the groups were detected. Consequently, the original design could not be implemented. With regards to performance, preference, and self-efficacy in the covert self-talk group no significant results were revealed, although there were potentially interesting patterns within the data. Content analysis of after performance debriefing interviews provided insights into participants‟ self-talk use and experimental experiences. The results are discussed in relation to theory, previous research, and methodological issues. Future research and applications are suggested. / Syftet med föreliggande studie var att undersöka: (1) effekterna av instruerande och motiverande self-talk yttrat overt eller kovert på self-efficacy och prestation hos elit golfspelare; samt (2) preferensen av motiverande eller instruerande self-talk och hur detta är relaterat till prestationen hos elit golfspelare. Deltog gjorde 30 elit golfspelare med en medelålder på 17.38 (± 0.94) år. En mixad design med upprepade mätningar implementerades. Manipuleringen av self-talk overtness i den overta self-talk gruppen misslyckades och skillnader mellan grupperna fanns i baslinjemätningen. Därav kunde inte den ursprungliga designen besvaras. Vad gäller prestation, preferens, och self-efficacy i den koverta self-talk gruppen fanns inga signifikanta resultat, men potentiellt intressanta trender fanns i datan. Kvalitativ innehållsanalys av prestations debriefings intervjuerna gav inblick i deltagarnas self-talk användning och upplevelser av experimentet. Resultaten diskuteras i relation till teoretiska ramverk, tidigare forskning, och metodiken i studien. Förslag på framtida forskning och praktiska implikationer ges.

The aim of this paper is discussion on particular aspects of the extension of a classic example in the design of experiments under the presence of correlated errors. Such extension allows us to study the effect of the correlation range on the design. We discuss the dependence of the information gained by the D-optimum design on the covariance bandwidth and also we concentrate to some technical aspects that occurs in such settings. (author's abstract) / Series: Research Report Series / Department of Statistics and Mathematics

The aim of this paper is discussion on particular properties of D-optimal designs under isotropic and intrinsically stationary correlation structures. We show that design points can collapse under the presence of some covariance structures. This enables to include so called nugget effect by natural way. Some numerical examples are also included. (author's abstract) / Series: Research Report Series / Department of Statistics and Mathematics

The massive volumes and the huge variety of large knowledge bases make information exploration and analysis difficult. An important activity is data filtering and selection, in which both querying and visualization play important roles. Interfaces for data exploration environments normally include both, integrating them as tightly as possible. But many features of information exploration environments, such as visual representation of queries, visualization of query results, interactive data selection from visualizations, have only been studied separately. The intrinsic connections between them have not been described formally. The lack of formal descriptions inhibits the development of techniques that produce new representations for queries, and natural integration of visual query specification with query result visualization. This thesis describes a formalism that describes the basic components of information exploration and and their relationships in information exploration environments. The key aspect of the formalism is that it unifies querying and visualization within a single framework, which provides a foundation for designing and analysing visual query interfaces. Various innovative designs of visual query representations can be derived from the formalism. Simply comparing them with existing ones is not enough, it is more important to discover why one visual representation is better or worse than another. To do this it is necessary to understand users’ cognitive activities, and to know how these cognitive activities are enhanced or inhibited by different presentations of a query so that novel interfaces can be created and improved based on user testing. This thesis presents a new experimental methodology for evaluating query representations, which uses stimulus onset asynchrony to separate different aspects of query comprehension. This methodology was used to evaluate a new visual query representation based on Karnaugh maps, and showing that there are two qualitatively different approaches to comprehension: deductive and inductive. The Karnaugh map representation scales extremely well with query complexity, and the experiment shows that its good scaling properties occur because it strongly facilitates inductive comprehension.

I gymnasieskolans kursplan för fysik är ett av målen att eleverna ska delta i planering och genomförande av enkla experiment. Eleverna ska introduceras i ett naturvetenskapligt arbetssätt som delvis består av undersökningar under laborativa former. Laborationer tar ofta en stor del av fysikundervisningen i anspråk. Inte sällan byggs undervisningen upp kring laborationerna. Den sociokulturella och konstruktivistiska teoribeskrivningen framhåller att lärande sker under processer då individen är aktiv. Fysikundervisningen bör alltså ha goda förutsättningar för elevernas lärande. Trots det är det många elever som har svårt att nå målen i fysik och intresset för att läsa fortsättningskurser minskar. Syftet med studien är att undersöka om det finns några speciella hinder under laborationen, som verkar negativt för elevernas lärande. Här undersöks elevernas uppfattningar om organisationen, framställningen och efterarbetet av laborationerna. Arbetet avser också söka svar på vilka metoder som är att föredra för att skapa gynnsamma förutsättningar för lärande. Studien bygger på en enkät som dels består av fasta svarsalternativ, dels av öppna frågor. Enkäten utfördes av 150 gymnasielever på fem olika skolor i Stockholmsområdet. Samtliga elever läser på naturvetenskapliga programmet i åk 1-3. Resultatet av studien visar att elever uppfattar laborationerna som goda lärsituationer då situationen präglas av enkelhet. Det innebär att instruktionerna är enkla att följa, lärarens vägledning är god och experimentet enkelt går att tolka på ett korrekt sätt. När eleverna kunde se händelseförloppet ansåg eleverna att det var lättare att ta till sig kunskaperna. Enkätsvaren antyder att eleverna föredrar lektionsaktiviteter som styrs av läraren där eleverna är mindre aktiva. Föreläsningar och demonstrationer är exempel på sådana situationer. Sådan undervisning kräver mindre resurser och är alltså ekonomiskt försvarbar. Att undersöka laborationens roll i undervisningen och effekt på elevernas kunskapsutveckling är därför viktigt.

The purpose of this paper is to investigate how individuals with different characteristics make their choice-decisions when consuming STIGA table tennis blades, which are combinations of various attributes, such as price, control, attack, etc. It is expected that the general trend of choice behavior on this special commodity can be, at least to some extent, revealed. Data were collected using questionnaires sent to registered members of a table tennis club in China. The questionnaires included information and questions about individuals’ monthly income levels, ages, technique styles, etc. A multinomial logit model was then applied to analyze factors determining Chinese consumers’ choice behavior on STIGA table tennis blades. The results indicated that the main element influencing Chinese consumers’ choice of STIGA ping-pong blades was the technique style and other variables did not seem to influence the choice of table tennis blades. These results might be explained by the limited sample size as well as unmeasured and immeasurable factors. Thus, a more extensive research is needed to be conducted in the future.

The Far-Offset Active-Source Imaging of Mantle (FAIM) experiment was conducted along an 800-km-long transect in the Western Atlantic to study the evolution of 108-157 m.y. lithosphere. The main transect (Line 1) crosses a transition from slow (13-14 mm/yr in half rate) to ultra-slow (~8 mm/yr) paleo spreading rates, and thus represents an ideal setting to study spreading-rate dependent processes as expressed in preserved lithospheric structure. This thesis presents results of four analysis efforts along this transect. We present a crustal model based on seismic refraction and wide-angle traveltime modeling, we extend the crustal model to an upper lithosphere density model using gravity constraints, we constrain Poissons ratio in oceanic Layer 3 using converted shear-wave phases, and we consider regional lithospheric structure by analysis of geoid/topography ratios. The crustal model indicates that a transition in crustal thickness accompanies the spreading-rate change, with the crust produced at slow rates being 1.0-1.5 km thinner. The gravity modeling shows that a density model can be constructed that simultaneously satisfies observed gravity, seismic constraints on crustal thickness, and our expectation of isostacy if ~1.3 km of low-density material is distributed into the upper 30-60 km of the mantle. This amount of material (~1.3 km) roughly equals the difference in thickness between slow and ultra-slow spreading crust, suggesting that that the thinner crust formed during very slow spreading arises due to melt retention in the mantle rather than decreased mantle melting. Modeling of mode-converted S-wave phases reveals a uniform of Poissons ratio (~0.27) in the lower crust. Along with the observation of sharp crust/mantle boundary, this result suggests that crust along the FAIM transect is primarily melt-derived igneous crust. Geoid versus topography relationships along Line 1 and nearby parallel tracks show abrupt changes that may originate from lateral changes in mantle density, possibly in response to the transition from slow to ultra-slow spreading. This type of observation may enable us to extend our inferences to a more regional scale.

For an offshore platform structure applied to wave-energy conversion system, in order to catch the maximum waves to generate more powers, similar to wind-energy power generators, a range of angles for the devices normal to the propagating direction of incident waves is required, particularly when the power converting system has directional preference. In this study, an electro-magnetic wave energy conversion device was developed and tested in a single-mooring offshore platform system. In order to find the best design parameters for the electro-magnetic generators system in various wave periods a water-tank experiment was designed and performed. During the experimental study, both wave parameters and dimensional related parameter of the generator were under investigation. It was found in this study that the newly developed wave conversion system can work well under certain periods and height of waves. The relationships between the parameter were presented into figures.

Wire bonding has been used in integrated circuit packaging for many decades because of its high reliability and performance. The most common metal used has been gold, but with the surge in commodity prices of gold in recent years, copper wire is now used to altered gold wire for cost saving. Many challenges have to be solved to meet its application requirement; coating is one of the applications. In this study, a 3D coated copper wire and coated Al pad is built by finite element method to simulate ultrasonic bonding and thermosonic bonding. To consider the effect of coated material to stress and strain field on ultrasonic bonding and the effect of coated material to temperature field on thermosonic bonding. Then use the Taguchi experiment method to discuss the effect on Cu-Ball and Al pad under different coated material and thickness combination. The results show that with coated material on Al pad or copper wire could reduce more than 48% of effective plastic strain after the bonding process, it obviously reduce the Al splash phenomenon in copper wire bonding. But the coated material such like palladium and nickel which have lower thermal conductivity would resist the heat transfer. And the Taguchi experiment method shows that the most effective way to reduce the effective stress during impact stage and ultrasonic vibration stage is to increase the thickness of palladium and nickel respectively, and when the thickness of coated material Au reached 0.01£gm could increase the temperature of Cu-Ball and Al pad mostly.