X-ray computed tomography is a nondestructive method for 3D imaging of inner structure of objects; it is, however, restricted by absorption properties of materials. With phase contrast imaging, observation of samples with low absorption or with parts with similar absorption becomes possible. For a long time, phase contrast imaging has been restricted to synchrotron radiation sources or special techniques due to requirement of spatial coherence of radiation. Along with recent development of X-ray micro and nanofocus tubes and X-ray detectors a phase contrast imaging becomes available also with laboratory sources. In this work an overview of phase contrast imaging methods is given, with an emphassis on propagation based method. Examples of this method and application of phase retrieval algorithm on samples from RIGAKU Nano3DX and GE phoenix v|tome|x L240 stations within Laboratory of X-ray micro and nanotomography CEITEC BUT are shown.

Computer vision and image processing systems are ubiquitous in automotive domain and manufacturing industry. Lane detection warning systems has been an elementary part of the modern automotive industry. Due to the recent progress in the computer vision and image processing methods, economical and flexible use of computer vision is now pervasive and computing with images is not just for the realm of the science, but also for the arts and social science and even for hobbyists. Image processing is a key technology in automotive industry, even now there is hardly a single manufacturing process that is thinkable without imaging. The applications of image processing and computer vision methods in embedded systems platform, is an ongoing research area since many years. OpenCV, an open-source computer vision library containing optimized algorithms and methods for designing and implementing applications based on video and image processing techniques. These method are organized in the form of modules for specific field including, user-graphic interface, machine learning, feature extraction etc [43]. Vision-based automotive application systems become an important mechanism for lane detection and warning systems to alert a driver about the road in localization of the vehicle [1]. In automotive electronic market, for lane detection problem, vision-based approaches has been designed and developed using different electronic hardware and software components including wireless sensor, camera module, Field-Programmable Gate Array (FPGA) based systems, GPU and digital signal processors (DSP) [13]. The software module consists on the top of real-time operating systems and hardware description programming language including Verilog, or VHDL. One of the most time critical task of vision based systems is to test system applications in real physical environment with wide variety of driving scenarios and validating the whole systems as per the automotive industry standards. For validating and testing the advanced driver assistance systems, there are some commercial tools available including Assist ADTF from Elektrobit, EB company [43]. In addition to the design and strict real-time requirements for advanced driver assistance systems applications based on electronic components and embedded platform, the complexity and characteristics of the implemented algorithms are two parameters that need to be taken into consideration choosing hardware and software component [13]. The development of vision-based automotive application, based on alone electronic and micro-controller is not a feasible solution approach [35] [13] and GPU based solution are attractive but has many other issues including power consumption. In this thesis project, image and video processing module is used from OpenCV library for road lane detection problems. In proposed lane detection methods, low-level image processing algorithms and methods are used to extract relevant information for lane detection problem by applying contrast analysis at pixel level intensity values. Furthermore, the work at hand presents different approaches for solving relevant partial problems in the domain of lane detection. The aim of the work is to apply contrast analysis based on low-level image processing methods to extract relevant lane model information from the grid of intensity values of pixel elements available in image frame. The approaches presented in this project work are based on contrast analysis of binary mask image frame extracted after applying range threshold. A set of points, available in an image frame, based lane feature models are used for detecting lanes on color image frame captured from video. For the performance measurement and evaluation, the proposed methods are tested on different systems setup, including Linux, Microsoft Windows, CodeBlocks, Visual Studio 2012 and Linux based Rasbian-Jessie operating systems running on Intel i3, AMD A8 APU, and embedded systems based (Raspberry Pi 2 Model B) ARM v7 processor respectively.

This master's thesis deals with study of the injected charge contrast mechanism of doped semiconductors by using the ultra – high vacuum scanning low electron energy microscope (UHV SLEEM). The aims of this work were to explain the injected charge contrast mechanism, to ability of this contrast mechanism to map the dopant density quantitatively and to identify the influencing factors.

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Studiens syfte är framtaget med bakgrund av att de fyra räknesätten och deras samband har visat sig viktiga för elevernas djupare förståelse inom matematik. Svenska elever i årskurs 4 visar att taluppfattning är det svåraste matematiska området i TIMSS 2015 trots att eleverna redan i årskurs 3 enligt den nuvarande läroplanen (Skolverket, 2011) ska ha arbetat med de fyra räknesätten och deras samband. Fokus i den här studien är multiplikations och divisions samband. Utifrån detta fanns ett behov att bidra med kunskap om elevernas uppfattningar om sambandet mellan räknesätten samt de missuppfattningar och svårigheter som kan uppstå när elevernas räknar med tal som fokuserar sambandet mellan multiplikation och division. Den här studiens syfte är att bidra med förståelse om elevernas uppfattningar och de kritiska aspekter för lärande som kan finnas i elevers förståelse av sambandet mellan division och multiplikation. Studien genomfördes med 8 elevintervjuer som metod, eleverna gick i årskurs 4. Studiens resultat visar att elevernas uppfattning om sambandet mellan multiplikation och division är tydliga när de berättar om sambandet men att det blir mer komplext när de ska lösa uppgifter. Resultatet visa även att 4 kritiska aspekter inom fenomenet sambandet mellan multiplikation och division har identifierats. De fyra kritiska aspekterna är skutträkning, att illustrera multiplikation och division med andra representationsformer än siffror, att skilja multiplikation från addition samt att dividera med 0,5.

The topic of this master thesis was the effects of pattern, size and background contrast of prey on discrimination learning of avian predators. The aim of this study was to investigate the influence of selected components of warning coloration on aversive discrimination learning of avian predators of different age and sex. The choosen model organism was the Great tit (Parus major). The comparision was done between hand-reared naïve birds and wild-caught adults of different age and sex. The experiment was taking place in the experimental cage with one way mirror. The experiment used a design of simultaneous task with two pray which differed in one component of the coloration (pattern, size and background kontrast). The differencies in the ability of discrimination learning was found just between hand-rared naïve birds and wild-caught adults. Better results were shown by the wild-caught adults. The ability of discrimination learning of wild-caught adults was not influenced by the age and sex. Pattern was the only significant component of the warning coloration due to which the birds were able to memorise the discrimination task. Key words: avoidance learning, unpalatable prey, pattern, size, background, contrast

This thesis aims to analyse several translations of J.D. Salinger's short story A Perfect Day for Bananafish: namely two translations and two edited versions of the latter one. The contrastive view is used to discern the main differences in meaning of the original and the translated texts. There are several points of view adopted to recognise the differences. On the syntactic level, the contrast between the texts was found to be present in the treatment of the author's style, predominantly in the narrative perspective. Not employing nominal structures a great deal, the author's style was not lost in the translation process. Comparing the translated texts, a tendency to adhere to the syntactic surface structure of the original text was found in the less recent versions. Another level of analysis explored the temporal relations of the texts, with the original text relying mostly on structures expressing sequences of events and also simultaneity of events, but not the perfective aspect to a great degree. These time relations are also found to be communicated in the translated texts successfully. It is not only the narrator that is discussed in this thesis, as a great portion of the short story consist of dialogues. The analysis aimed, using certain excerpts of the story, to find to what degree...

Syftet med denna studie är att undersöka hur några elever i årskurs 1 skapar förståelse för vad en teknisk artefakt är och vidare hur eleverna ges möjlighet till detta genom att läraren använder variationsmönster under ett lektionstillfälle. Materialet har samlats in genom en learning study vilket innebär att vi har genomfört en praxisnära undersökning. Vi har i studien agerat både forskare och lärare; observerat, planerat och bedrivit undervisning samt analyserat empirin. Vi har studerat tre lektionstillfällen i tre olika grupper med fokus på att tillsammans med eleverna skapa en definition av vad en teknisk artefakt är. Med hjälp av för- och eftertester har vi även undersökt elevernas uppfattningar om tekniska artefakter före och efter lektionstillfället. Som analysredskap har vi använt variationsteori och de begrepp som den innefattar samt kritiska aspekter. Vi jämför sedan resultatet med tidigare forskning. Resultaten visar att lärarens brister och förtjänster påverkar det intentionella lärandeobjektet, det vill säga om eleverna lär sig eller inte. Studien visar även att andra faktorer påverkar lärandet. Eleverna inte har några svårigheter med att urskilja högteknologiska artefakter men hade svårt att förvärva sig förståelsen för att ett naturligt föremål som bearbetas blir till ett tekniskt föremål. Anmärkningsvärt med studien var att vi upptäckte att flera elever tänker cykliskt när de tänker på en teknisk artefakt då de ser till hela tillverkningsprocessen.

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Syfte: Syftet med denna studie var att jämföra Multilens Bilux Iris-glas mot deras vanliga polariserade filterglas på syncentralspatienter med uttalade bländningsbesvär. Metod: I studien undersöktes 15 personer mellan 42-89 år. Försökspersonerna som hade bokad tid hos Syncentralen i Kalmar fick valet att ställa upp på en studie där de skulle få testa ytterligare ett filterglas. Patienterna återkallades efter ett par veckor då synskärpetester gjordes i hög och lågkontrast med och utan bländningsbelysning. Undersökningen innefattade även en intervju under vilken patienten fick berätta vad han/hon tyckte om respektive glas. Resultat: Kontrast påverkade visus. Högkontrast visus påverkades inte nämnvärt med olika filterglasen eller bländning. För lågkontrast visus fanns heller ingen signifikant skillnad mellan filterglasen med eller utan bländning. En del patienter upplevde bättre synförhållanden med Bilux i vissa situationer. Slutsats: Högkontrast samt lågkontrast visus påverkades inte nämnvärt med de olika filterglasen eller med bländning. Subjektivt upplevdes förbättrade synförhållanden i vissa situationer med Bilux och vanliga filterglas. / The aim of this study was to compare Multilens Bilux Iris against their regular polarized filter-glasses on low vision subjects with pronounced light sensitivity. A total of 15 people aged 42-89 years participated in the study. All were patients at the low-vision clinic at the hospital in Kalmar, Sweden. Patients were recruited during a prior routine examination whereby they were asked if they would be willing to participate in a study in which they would have the chance to try an extra pair of filter-glasses. The patients were recalled after a few weeks for the examination. Patients’ high- and low contrast visual acuity was measured both with and without glare. An interview with all of the patients was also conducted regarding the different filter lenses. This study showed no significant difference in high contrast or low contrast visual acuity, with or without the different filters examined during this study. A subjective difference was however detected between filters under certain situations.