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The reflection performance of periodic acoustic metasurfaces (AMs) subjected to a grazing flow, consisting of a uniform region and a finite sheared layer, is studied. A convective generalized Snell's law (CGSL) is derived to account for the effect of uniform mean flows on the reflection of AMs. Then, an AMs design method considering the mean flow profile is proposed based on the impedance transformation method. The strategy is to form a reflected phase gradient at the interface plane between the uniform and the sheared flow regions. The reflection characteristics of two acoustic porous metasurfaces (APMs), i.e., APM1 and APM2 designed for the uniform and the sheared flows, respectively, are numerically investigated. Results show that APM1 achieves efficient anomalous reflections in uniform flows, and the diffracted orders and directions of the reflected waves are well predicted by the proposed CGSL. However, the performance of APM1 deteriorates under oblique incidences if applied to a typical sheared flow. In contrast, APM2 realizes desired wavefront manipulations under the same conditions. Finally, the CGSL is extended into a three-dimensional (3D) space and is validated numerically. This study provides a means for AMs design in flow conditions, which holds good potential in aeroacoustic noise problems.

This work deals with definition of garments. It explores how little changes a piece of fabric needs to still make it into a garment. What is it that defines a garment, is it just that something is done with a piece of fabric or does it need some recognizing of body parts. The aim is to find new ways of construction without using templates and questioning when textile becomes garments by draping and cutting.Through using how clothes are fitted to the body but instead of using pattern templates work from a rectangle and make it fit the body as garment. Working from two-dimensional to three-dimensional by the help of the body, going directly from fabric to garment. By defining the essential parts in every garment and cutting holes in a rectangle to highlight a certain body part or letting the body go trough different holes to make the fabric turn and drape around the body. Conclusion of the work is that a cut or incision doesn’t always define a garment, that it takes another recognition as well to make the definition. During the development questions have arise as for example how to construct holes in all fabrics and deal with the finishing, how to use raw edges without ripping, how to sew were there is no seam allowance and how to create fabric suited for cutting., Program: Modedesignutbildningen

This work deals with definition of garments. It explores how little changes a piece of fabric needs to still make it into a garment. What is it that defines a garment, is it just that something is done with a piece of fabric or does it need some recognizing of body parts. The aim is to find new ways of construction without using templates and questioning when textile becomes garments by draping and cutting.Through using how clothes are fitted to the body but instead of using pattern templates work from a rectangle and make it fit the body as garment. Working from two-dimensional to three-dimensional by the help of the body, going directly from fabric to garment. By defining the essential parts in every garment and cutting holes in a rectangle to highlight a certain body part or letting the body go trough different holes to make the fabric turn and drape around the body. Conclusion of the work is that a cut or incision doesn’t always define a garment, that it takes another recognition as well to make the definition. During the development questions have arise as for example how to construct holes in all fabrics and deal with the finishing, how to use raw edges without ripping, how to sew were there is no seam allowance and how to create fabric suited for cutting., Program: Modedesignutbildningen

While color video endoscopy has enabled wide-field examination of the gastrointestinal tract, it often misses or incorrectly classifies lesions. Many of these missed lesions exhibit characteristic three-dimensional surface topographies. An endoscopic system that adds topographical measurements to conventional color imagery could therefore increase lesion detection and improve classification accuracy. We introduce photometric stereo endoscopy (PSE), a technique which allows high spatial frequency components of surface topography to be acquired simultaneously with conventional two-dimensional color imagery. We implement this technique in an endoscopic form factor and demonstrate that it can acquire the topography of small features with complex geometries and heterogeneous optical properties. PSE imaging of ex vivo human gastrointestinal tissue shows that surface topography measurements enable differentiation of abnormal shapes from surrounding normal tissue. Together, these results confirm that the topographical measurements can be obtained with relatively simple hardware in an endoscopic form factor, and suggest the potential of PSE to improve lesion detection and classification in gastrointestinal imaging.