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Die vorliegende Arbeit ist in einen hermeneutischen und einen empirischen Teil untergliedert. Die hermeneutisch bearbeiteten Kapitel informieren über das nötige Hintergrundwissen, welches für die Planung, Durchführung, Auswertung sowie Analyse der Interviews notwendig ist. In Kapitel 2 wird das Auge zunächst anatomisch und funktionell behandelt, um im Folgenden die Gründe für Sehbeeinträchtigungen bei Kindern sowie Definitionen und Klassifizierungen in Bezug auf Sehschwächen anzuführen. Kapitel 3 behandelt die Bedeutung des Sports zunächst allgemein, geht dann aber speziell auf die beiden Schwerpunkte Bedeutung des Sports bei Kindern sowie Bedeutung des Sports bei Menschen mit Beeinträchtigungen ein. Dabei kam heraus, dass Sport einen sehr hohen Stellenwert in der österreichischen Bevölkerung einnimmt und es zahlreiche Motive für die Sportausübung gibt. Das darauf folgende Kapitel 4 setzt sich ausführlich mit dem Allgemeinen Skilehrweg auseinander, um Gemeinsamkeiten und Unterschiede mit dem Kinderskilehrweg und mit Besonderheiten für den Skilauf mit sehbeeinträchtigten Menschen aufzuzeigen. Es stellte sich heraus, dass der Kinderskilehrweg leichte Abwandlungen hat, es bei den Blindensportler(inne)n jedoch keinerlei Unterschiede hinsichtlich des Lehrweges, sondern alleine in der Umsetzung gibt. Mit Kapitel 5 beginnt der empirische Teil der vorliegenden Arbeit, indem die Herangehensweise genauer erklärt wird. Als qualitative Methode wurden leitfadenorientierte Expert(inn)en-Interviews geführt, welche mit Hilfe der Vertiefenden Fallanalyse untersucht wurden.

This work describes the development and fabrication of a novel nanofluidic flow-through sensing chip that utilizes a plasmonic resonator to excite fluorescent tags with sub-wavelength resolution. We cover the design of the microfluidic chip and simulation of the plasmonic resonator using Finite Difference Time Domain (FDTD) software. The fabrication methods are presented, with testing procedures and preliminary results. This research is aimed at improving the resolution limits of the Direct Linear Analysis (DLA) technique developed by US Genomics [1]. In DLA, intercalating dyes which tag a specific 8 base-pair sequence are inserted in a DNA sample. This sample is pumped though a nano-fluidic channel, where it is stretched into a linear geometry and interrogated with light which excites the fluorescent tags. The resulting sequence of optical pulses produces a characteristic "fingerprint" of the sample which uniquely identifies any sample of DNA. Plasmonic confinement of light to a 100 nm wide metallic nano-stripe enables resolution of a higher tag density compared to free space optics. Prototype devices have been fabricated and are being tested with fluorophore solutions and tagged DNA. Preliminary results show evanescent coupling to the plasmonic resonator is occurring with 0.1 micron resolution, however light scattering limits the S/N of the detector. Two methods to reduce scattered light are presented: index matching and curved waveguides.

In this work, we present a novel, fast clustering scheme for codebook generation from local features for object class recognition. It relies on a sequential data analysis and creates compact clusters with low variance. We compare our algorithm to other commonly used algorithms with respect to cluster statistics and classification performance. It turns out that our algorithm is the fastest for codebook generation, without loss in classification performance, when using the right matching scheme. In this context, we propose a well suited matching scheme for assigning data entries to cluster centers based on the sigmoid function.

Content based automatic image classification systems are increasingly finding usage, e.g. in large medical image databases. This paper concentrates on a grayscale radiograph annotation task which was a part of the ImageCLEF 2006. We use local features calculated around interest points, which have recently received excellent results for various image recognition and classification tasks. We propose the use of relational features, which are highly robust to illumination changes, and thus quite suitable for X-Ray images. Results with various feature and classifier settings are reported. A significant improvement in results is seen when the relative positions of the interest points are also taken into account during matching. For the given test set, our best run had a classification error rate of 16.7 %, just 0.5 % higher than the best overall submission, and therewith was ranked second in the medical automatic annotation task at the ImageCLEF 2006. The proposed method is general, can be applied to other image classification tasks and can also be extended to colour images.

We have fabricated polycrystalline diamond hemispheres by hot-filament CVD (HFCVD) in spherical cavities wet-etched into a high temperature glass substrate CTE matched to silicon. Hemispherical resonators 1.4 mm in diameter have a Q of up to 143 000 in the fundamental wineglass mode, for a ringdown time of 2.4 s. Without trimming, resonators have the two degenerate wineglass modes frequency matched as close as 2 Hz, or 0.013% of the resonant frequency (~16 kHz). Laser trimming was used to match resonant modes on hemispheres to 0.3 Hz. Experimental and FEA energy loss studies on cantilevers and hemispheres examine various energy loss mechanisms, showing that surface related losses are dominant. Diamond cantilevers with a Q of 400 000 and a ringdown time of 15.4 s were measured, showing the potential of polycrystalline diamond films for high Q resonators. These resonators show great promise for use as hemispherical resonant gyroscopes (HRGs) on a chip.

Image classification systems have received a recent boost from methods using local features generated over interest points, delivering higher robustness against partial occlusion and cluttered backgrounds. We propose in this paper to use relational features calculated over multiple directions and scales around these interest points. Furthermore, a very important design issue is the choice of similarity measure to compare the bags of local feature vectors generated by each image, for which we propose a novel approach by computing image similarity using cluster co-occurrence matrices of local features. Excellent results are achieved for a widely used medical image classification task, and ideas to generalize to other tasks are discussed

We describe and compare three probabilistic ways to perform Content Based Image Retrieval (CBIR) in compressed domain using images in JPEG2000 format. Our main focus are arbitrary non-uniformly textured color images, as can be found, e.g., in home user image collections. JPEG2000 offers data that can be easily transferred into features for image retrieval. Thus, when converting images to JPEG2000, feature extraction comes at a low cost. For feature creation, wavelet subband data is used. Color and texture features are modelled independently and can be weighted by the user in the retrieval process. For texture features in common databases, we show in which cases modelling wavelet coefficient distributions with Gaussian Mixture Models (GMM) is superior in to approaches with Generalized Gaussian Densities (GGD). Empirical tests with data collected by non-expert users evaluate the usefulness of the ideas presented.

III-V based single photon avalanche diodes (SPADs), avalanche photodiodes (APDs) operated in Geiger-mode, are ideally suited for ultra-weak signal detection in the near infrared for photon counting and photon timing applications. Spaceborne SPADs would provide a rugged, compact alternative to photomultiplier tubes with lower operating voltage requirements, stronger near-IR response, and the possibility for array implementation. Results from a performance characterization of an in-house fabricated In0.53Ga0.47As/InP SPAD are presented. Sensitivity (NEP) and timing resolution (δt) were investigated as a function of bias from T = 135 K to 165 K; an NEP ≈ 5 x 1015W/Hz1/2 at T = 150 K and δt ≈ 230 ps at T = 165 K were measured for λ = 1.55 μm light.

Epitaxial layer transfer was used to fabricate In/sub 0.53/Ga/sub 0.47/As-InP avalanche photodiodes on GaAs substrates. The photodiodes displayed a gain-bandwidth product of 80 GHz, dark current of 10.20 nA at 90% of the breakdown voltage, and responsivity of 5.9 A/W at 2 V below breakdown. Performance is comparable to standard devices fabricated on InP substrates, suggesting the transfer process does not degrade material quality.

In this paper we report the fabrication of hemispherical polycrystalline diamond resonators fabricated on a novel high-temperature glass substrate. The hemispherical resonator gyroscope is one of the most accurate and rugged of the mechanical gyroscopes, and can be operated in either rate or whole-angle mode due to its high degree of symmetry. A fabrication sequence for creating extremely symmetric 3D MEMS hemispheres is presented. Mode shapes and frequencies obtained with a laser vibrometer are shown, as well as curves of Q versus pressure, and the dependence of frequency on anchor size. Fundamental mode frequency matching to

Lipoblastoma is an uncommon benign lipomatous soft tissue mass of childhood, occurring most commonly in children less than 3 years of age. We present a case of lipoblastoma occurring in the foot of a 14-year-old boy and review the literature. The appearance of the mass on magnetic resonance imaging (MRI) is illustrated and is correlated with the findings at gross and microscopic pathological examination. A lobulated architecture, the presence of adipose tissue, thin nonenhancing septa, peripheral lobules of more immature and therefore less specific tissue, and a peripheral pseudocapsule were evident on MRI and at pathological examination.

Dendranthema grandiflora Tzvelev (Chrysanthemum morifolium Ramat.) garden cultivars Vulcan, with deep red ray florest, and Superior, with orange ray petals, were crossed as female with 16 inbred clones and the progeny assessed visually for flower color in 3 environments. Intensity of vacuole pigmentation in ray florets appeared to vary continuously. Evaluation was facilitated by placing plants in 7 color classes ranging from red, the most intense, through orange, an intermediate intensity, to yellow, the apparent lack of vacuole pigmentation. A simple hexaploid model with additive gene action, suggested by the 7 color classes, was inappropriate, as more than 50% of the plants in ‘Vulcan’ families were red and more than 60% of the plants in ‘Superior’ families were orange. Comparing evaluations of parental clones in 2 glasshouse and 2 field environments and considering data from an experiment, in which progeny first classified in the glasshouse were reevaluated in the field, revealed substantial shifts in classification. In the glasshouse, more individuals appeared in the red and orange classes, while field evaluation placed more individuals in classes adjacent to red and orange. However, the predominance of progeny in the color class of the common parent, that is, red for the ‘Vulcan’ and orange for the ‘Superior’ families, occurred in both glasshouse and field. Plants scored as other than red appeared in crosses between ‘Vulcan’ and 3 red inbreds, suggesting that red ray petals are not conditioned by a homozygous genotype. The orange of ‘Superior’ and orange progeny may be due to a single dominant gene causing mosaic-like distribution of red vacuole pigmentation over yellow plastid pigmentation. Because cloned genotypes were classified differently in diverse environments, critical genetic analysis of vacuole pigmentation will require cloned progeny and multiple-environment evaluation.

Two hundred one tibial shaft fractures, 160 closed and 41 open (Grades I and II), were treated between January 1978 and June 1982. Sixty patients underwent closed intramedullary Arbeitsgemeinschart Osteosynthesisfragen/Association for the Study of Problems of Internal Fixation (AO/ASIF) nailing with reaming and 141 patients were treated with closed reduction and cast immobilization. Intramedullary nailing resulted in one (1.7%) nonunion, two (3.3%) infections, and no malunions. In the cast treatment group there were 14 (9.9%) delayed or nonunions, two (1.4%) infections, and six (4.3%) malunions. Within this group there were 19 early failures from either inadequate reduction or loss of reduction, which led to a change from nonoperative to operative methods of management. The interval between injury and return to work was 22 weeks in the nailed group, compared with 25.8 weeks in the cast immobilization group.