Threshold modulation in 1-D error diffusion

Error diffusion (ED) is widely used in digital imaging as a binarization process which preserves fine detail and results in pleasant images. The process resembles the human visual system in that it exhibits an intrinsic edge enhancement An additional extrinsic edge enhancement can be controlled by varying the threshold. None of these characteristics has yet been fully explained due to the lack of a suitable mathematical model of the algorithm. The extrinsic sharpening introduced in 1-D error diffusion is the subject of this thesis. An available pulse density modulation(PDM) model generated from a frequency modulation is used to gain a better understanding of variables in ED. As a result, threshold variation fits the model as an additional phase modulation. Equivalent images are obtained by applying ED with threshold modulation or by preprocessing an image with an appropriate convolution mask and subsequently running standard ED

Effekten van niet-stoichiometrie in DyAlG een-kristallen

SIGLEKULeuven Campusbibliotheek Exacte Wetenschappen / UCL - Université Catholique de LouvainBEBelgiu

Breeding or assisted reproduction? : relevance of the horse model applied to the conservation of endangered equids

Many wild equids are at present endangered in the wild. Concurrently, increased mechanization has pushed back the numbers of some old native horse breeds to levels that are no longer compatible with survival of the breed. Strong concerns arose in the last decade to preserve animal biodiversity, including that of rare horse breeds. Genome Resource Banking refers to the cryostorage of genetic material and is an approach for ex situ conservation, which should be applied in combination with in situ conservation programmes. In this review, we propose that, owing to the great reproductive similarity among the different members of the genus Equus, the domestic horse can be used to optimize cryopreservation and embryo production protocols for future application in wild equids. We will give this hypothesis a scientific underpinning by listing successful applications of epididymal sperm freezing, embryo freezing, intracytoplasmic sperm injection, oocyte vitrification and somatic cell nuclear transfer in domestic horses. Some ART fertilization methods may be performed with semen of very low quality or with oocytes obtained after the death of the mare