Dissertations / Theses: 'Improving the Skin Texture'

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Rowe, Dale Christopher. "Face recognition using skin texture." Thesis, University of Kent, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528278.

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Al-Qarni, Garsah Farhan. "Skin texture features for face recognition." Thesis, University of Kent, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633831.

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Face recognition has been deployed in a wide range of important applications including surveillance and forensic identification. However, it still seems to be a challenging problem as its performance severely degrades under illumination, pose and expression variations, as well as with occlusions, and aging. In this thesis, we have investigated the use of local facial skin data as a source of biometric information to improve human recognition. Skin texture features have been exploited in three major tasks, which include (i) improving the performance of conventional face recognition systems, (ii) building an adaptive skin-based face recognition system, and (iii) dealing with circumstances when a full view of the face may not be avai'lable. Additionally, a fully automated scheme is presented for localizing eyes and mouth and segmenting four facial regions: forehead, right cheek, left cheek and chin. These four regions are divided into nonoverlapping patches with equal size. A novel skin/non-skin classifier is proposed for detecting patches containing only skin texture and therefore detecting the pure-skin regions. Experiments using the XM2VTS database indicate that the forehead region has the most significant biometric information. The use of forehead texture features improves the rank-l identification of Eigenfaces system from 77.63% to 84.07%. The rank-l identification is equal 93.56% when this region is fused with Kernel Direct Discriminant Analysis algorithm.

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Pinheiro, Jefferson Magalhães. "A procedural model for snake skin texture generation." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/171371.

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Existem milhares de espécies de serpentes no mundo, muitas com padrões distintos e intricados. Esta diversidade se torna um problema para usuários que precisam criar texturas de pele de serpente para aplicar em modelos 3D, pois a dificuldade em criar estes padrões complexos é considerável. Nós primeiramente propomos uma categorização de padrões de pele de serpentes levando em conta suas características visuais. Então apresentamos um modelo procedural capaz de sintetizar uma vasta gama de textura de padrões de pele de serpentes. O modelo usa processamento de imagem simples (tal como sintetizar bolinhas e listras) bem como autômatos celulares e geradores de ruído para criar texturas realistas para usar em renderizadores modernos. Nossos resultados mostram boa similaridade visual com pele de serpentes reais. As texturas resultantes podem ser usadas não apenas em computação gráfica, mas também em educação sobre serpentes e suas características visuais. Nós também realizamos testes com usuários para avaliar a usabilidade de nossa ferramenta. O escore da Escala de Usabilidade do Sistema foi de 85:8, sugerindo uma ferramenta de texturização altamente efetiva.<br>There are thousands of snake species in the world, many with intricate and distinct skin patterns. This diversity becomes a problem for users who need to create snake skin textures to apply on 3D models, as the difficulty for creating such complex patterns is considerable. We first propose a categorization of snake skin patterns considering their visual characteristics. We then present a procedural model capable of synthesizing a wide range of texture skin patterns from snakes. The model uses simple image processing (such as synthesizing spots and stripes) as well as cellular automata and noise generators to create realistic textures for use in a modern renderer. Our results show good visual similarity with real skin found in snakes. The resulting textures can be used not only for computer graphics texturing, but also in education about snakes and their visual characteristics. We have also performed a user study to assess the usability of our tool. The score from the System Usability Scale was 85:8, suggesting a highly effective texturing tool.

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Round, Andrew John. "Texture and colour for automatic image-based skin lesion analysis." Thesis, Bangor University, 1998. https://research.bangor.ac.uk/portal/en/theses/texture-and-colour-for-automatic-imagebased-skin-lesion-analysis(6f44bc07-d680-4aee-941b-49ba4ddd5314).html.

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The research presented here considers automatic diagnosis support for skin cancer. The role of computer-based diagnosis, and its value within a primary care situation are examined resulting in synthesis of aims, requirements and properties for an effective system -a system based on digital optical images captured and processed using low-cost commercial computer technology. The issues involved in acquisition of lesion boundaries are discussed. The value of accurate and robust boundaries, in terms of both directly obtainable diagnostic features and in enabling lesion property evaluation, is identified. Previous research has proposed the edge focusing process. This work has addressed the improvement, in terms of potential for future development, evaluation and reuse, of this process through porting it to a highly modular form in the Khoros environment. The role of colour analysis and its value in terms of provision of diagnostically useful features is investigated, and the central importance of segmentation is identified. The fundamental properties of effective segmentation of lesion image colours are identified as a need to reflect human perception of colour similarity and a basis on local regions. A new region-based segmentation technique using data transformed to a perception-uniform colour-space is presented and shown to yield promising results. Finally the use of texture information is discussed. The nature and properties of the large-scale texture of skin patterning and its disruption are investigated and an abstracted representation proposed. A new technique is presented and shown to be effective in extracting the qualities of the skin patterning. Methods for analysing this representation of the patterning to quantify the disruption attributable to the lesion are proposed and developed. The combination of these extraction, analysis and disruption evaluation techniques is shown to be effective in relation to both visual assessment of disruption and diagnostic performance.

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Holmberg, Björn. "Estimating Human Limb Motion Using Skin Texture and Particle Filtering." Doctoral thesis, Uppsala universitet, Avdelningen för systemteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9352.

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Estimating human motion is the topic of this thesis. We are interested in accurately estimating the motion of a human body using only video images capturing the subject in motion. Video images from up to two cameras are considered. The first main topic of the thesis is to investigate a new type of input data. This data consists of some sort of texture. This texture can be added to the human body segment under study or it can be the actual texture of the skin. In paper I we investigate if added texture together with the use of a two camera system can provide enough information to make it possible to estimate the knee joint center location. Evaluation is made using a marker based system that is run in parallel to the two camera video system. The results from this investigation show promise for the use of texture. The marker and texture based estimates differ in absolute values but the variations are similar indicating that texture is in fact usable for this purpose. In paper II and III we investigate further the usability in images of skin texture as input for motion estimation. Paper II approaches the problem of estimating human limb motion in the image plane. An image histogram based mutual information criterion is used to decide if an extracted image patch from frame k is a good match to some location in frame k+1. Eval- uation is again performed using a marker based system synchronized to the video stream. The results are very promising for the application of skin texture based motion estimation in 2D. In paper III, basically the same approach is taken as in paper II with the substantial difference that here estimation of three dimensional motion is addressed. Two video cameras are used and the image patch matching is performed both between cameras (inter-camera) in frame k and also in each cameras images (intra-camera) for frame k to k+1. The inter-camera matches yield triangulated three dimensional estimates on the approximate surface of the skin. The intra-camera matches provide a way to connect the three dimensional points between frame k and k+1 The resulting one step three dimensional trajectories are then used to estimate rigid body motion using least squares methods. The results show that there is still some work to be done before this texture based method can be an alternative to the marker based methods. In paper IV the second main topic of the thesis is discussed. Here we present an investigation in using model based techniques for the purpose of estimating human motion. A kinematic model of the thigh and shank segments are built with an anatomic model of the knee. Using this model, the popular particle filter and typical simulated data from the triangulation in paper III, an estimate of the motion variables in the thigh and shank segment can be achieved. This also includes one static model parameter used to describe the knee model. The results from this investigation show good promise for the use of triangulated skin texture as input to such a model based approach.

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Paoli, John. "Selected aspects on improving the management of skin cancer /." Göteborg : Dept. of Dermatology and Veneorology, Sahlgrenska University Hospital, Institute of Clinical Sciences at the Sahlgrenska Academy, University of Gothenburg, 2009. http://hdl.handle.net/2077/20104.

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Tan, Siao Pei. "Improving the skin barrier function in atopic dermatitis." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/11735.

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Atopic dermatitis, AD (synonym eczema) is a chronic inflammatory skin disease. It affects between 10 to 20% of children and 1 to 3% of adults worldwide. It is an important cause of morbidity and is estimated to cost £465 million per annum to the UK. AD is part of a family of Th-2 driven diseases and is often the first of these atopic diseases to manifest. The development of AD is often followed by asthma and allergic rhinitis later in life (a phenomenon known as the ‘atopic march’). Up to 50% of moderate to severe AD cases have been associated with genetic mutations affecting the epidermal barrier protein filaggrin. Filaggrin aggregates keratin filaments during terminal keratinocyte differentiation, allowing normal epidermal stratification. The role of filaggrin in maintaining a functional skin barrier is further supported by a clinical study conducted by ourselves. This is the first clinical study on a European cohort (58 participants) which showed that FLG mutations were associated with experimentally demonstrable defects of skin barrier function (increased baseline transepidermal water loss), more so following exposure to a chemical irritant. However, the majority of patients with AD, especially the milder cases, do not have FLG mutations. Some of the wild-type patients in our study were noticed to have accumulation of the large filaggrin proprotein and a lack of filaggrin monomers, indicating defective proteolysis of profilaggrin into the functional monomers. Our study also found disproportionately raised protease inhibitory activities amongst the AD participants. This inappropriately raised protease inhibition may interfere with profilaggrin proteolysis, leading to the development of AD in some wild-type patients. Having demonstrated that deficiency of filaggrin monomers is associated with a defective skin barrier, we focused on the function of filaggrin in the skin and attempted to improve the skin barrier function. In addition to keratin aggregation, filaggrin constitutes the natural moisturizing factors in the epidermis following its natural breakdown into amino acids. We note that filaggrin is disproportionately rich in amino acid histidine, implying that this amino acid may have a particular significance in maintaining a functional epidermal barrier. Using an in-house skin-equivalent model, we have shown that by increasing the histidine content in the cell culture media, we could increase the expression of filaggrin monomers and reduce the penetration of a fluorescent dye into the skin-equivalents. The latter indicates improved barrier function. Finally, we conducted a pilot human study which showed that histidine, when applied to mechanically damaged skin in AD and healthy participants, was associated with a faster recovery of the skin barrier function. These studies suggest that histidine is of therapeutic benefits in AD. A histidine-based treatment may be developed as an alternative to current anti-inflammatory and immunosuppressive agents used to treat AD.

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Chong, Cassandra. "Improving 3D Scaffolds for Skin Tissue Engineering using Advanced Biotechnology." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16551.

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Existing, dermal, regenerative scaffolds facilitate dermal repair and wound healing of severe burn injuries; however, new tissue is often functionally, mechanically and aesthetically abnormal due to irregular deposition of new extracellular matrix. In the present study two novel, elastin-containing scaffolds were developed, characterised and examined both in vitro and in vivo aiming to minimise wound contraction, improve scar appearance and increase skin elasticity post-healing. The first types of scaffolds were electrospun from a triple polymer solution of collagen, elastin and poly(ϵ-caprolactone) (CEP). Two scaffolds were chosen for characterisation: CEP 1 was fabricated using a 1.5 % (w/v) collagen, 12 % (w/v) elastin and 1.5 % (w/v) poly(ϵ-caprolactone) (PCL) solution, a flow rate of 3 mL/h, an air gap of 15 cm and an applied electric potential of 25 kV; and CEP 2 was electrospun using a 2 % (w/v) collagen, 12 % (w/v) elastin and 1 % (w/v) PCL solution at 1 mL/h, 20 cm and 20 kV. In vitro cell studies using human, dermal fibroblasts (HDFs) and immortalised, human keratinocytes (HaCaTs) revealed CEP 1 and CEP 2 supported cell-seeding and cell proliferation with significantly higher proliferation of both cell types on CEP 1. Additionally, subcutaneous implant studies in mice revealed minimal inflammation in response to both scaffolds with CEP 1 vascularised by week 2 post-surgery. However, CEP 1 was rapidly biodegraded after 2 weeks. Collagen deposition was observed in encapsulating tissue and new tissue with consistent collagen expression over 24 weeks. The second type of scaffold investigated was an elastin-modified version of the commercial, dermal substitute Integra Dermal Regeneration Template (IDRT). Elastin-IDRT (EDRT) was developed by inclusion of 10% human tropoelastin and then investigated in comparison with IDRT. Morphological analysis by scanning electron microscope and mechanical characterisation revealed EDRT had significantly enlarged pores, higher porosity and increased deformability. Higher cell seeding efficiency of HaCaTs on EDRT was observed compared to IDRT but cell proliferation rate was found to be similar over 28 days. HDFs displayed increased cell growth rate on EDRT over 28 days compared to IDRT. Enhanced and accelerated HDF infiltration of EDRT was also visualised with complete infiltration by day 14 post-seeding. An in vivo, mouse, subcutaneous implant model showed that EDRT induced minimal inflammation. Gene expression of mouse collagen was consistent over 24 weeks with non-significant increases in elastin expression from weeks 2 and 4. One-step grafting demonstrated similar contraction between EDRT-, IDRT- and autografted wounds with final contraction around 40 % compared to 100 % in open wounds. EDRT displayed significantly accelerated, early-stage angiogenesis with higher vascularisation than IDRT-grafted, autografted or open wounds 2 weeks post grafting. By week 4 EDRT- and IDRT-grafted wounds had similar levels of vascularisation which were higher than autografted and open wounds. EDRT showed improved mechanical performance, supported enhanced cell interactions in vitro and accelerated angiogenesis in vivo. In summary, investigated scaffolds demonstrated properties that could potentially improve burn wound healing. The inclusion of elastin in scaffolds produced by either electrospinning or lyophilisation improved HDF infiltration and supported formation of a confluent layer of HaCaTs which could result in increased pliability of new skin and accelerated wound healing. In EDRT elastin improved scaffold porosity, pore size and accelerated angiogenesis in vivo indicating EDRT can facilitate and improve wound remodelling. Further investigation of both scaffolds is warranted especially due to the vascular inductive effects of EDRT and the synchronous spatial and temporal biodegradation of CEP 2 observed in vivo.

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Skedung, Lisa. "Tactile Perception : Role of Friction and Texture." Doctoral thesis, KTH, Yt- och korrosionsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-103916.

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Tactile perception is considered an important contributor to the overall consumer experience of a product. However, what physical properties that create the specifics of tactile perception, are still not completely understood. This thesis has researched how many dimensions that are required to differentiate the surfaces perceptually, and then tried to explain these dimensions in terms of physical properties, by interconnecting human perception measurements with various physical measurements. The tactile perception was assessed by multidimensional scaling or magnitude estimation, in which methods human participants assign numbers to how similar pairs of surfaces are perceived or to the relative quantity of a specified perceptual attribute, such as softness, smoothness, coarseness and coolness. The role of friction and surface texture in tactile perception was investigated in particular detail, because typically tactile exploration involves moving (at least) one finger over a textured surface. A tactile approach for measuring friction was developed by means of moving a finger over the surfaces, mounted on a force sensor. The contribution of finger friction to tactile perception was investigated for surfaces of printing papers and tissue papers, as well as for model surfaces with controlled topography. The overarching research goal of this thesis was to study, systematically, the role of texture in tactile perception of surfaces. The model surfaces displayed a sinusoidal texture with a characteristic wavelength and amplitude, fabricated by surface wrinkling and replica molding techniques. A library of surfaces was manufactured, ranging in wavelengths from 270 nm up to 100 µm and in amplitudes from 7 nm up to 6 µm. These surfaces were rigid and cleanable and could therefore be reused among the participants. To my knowledge, this is the first time in a psychophysical experiment, that the surface texture has been controlled over several orders of magnitude in length scale, without simultaneously changing other material properties of the stimuli. The finger friction coefficient was found to decrease with increasing aspect ratio (amplitude/wavelength) of the model surfaces and also with increasing average surface roughness of the printing papers. Analytical modeling of the finger’s interaction with the model surfaces shows how the friction coefficient increases with the real contact area, and that the friction mechanism is the same on both the nanoscale and microscale. The same interaction mechanism also explains the friction characteristics of tissue paper. Furthermore, it was found that the perceptions of smoothness, coarseness, coolness and dryness are satisfactorily related to the real contact area at the finger-surface interface. It is shown that it is possible to discern perceptually among both printing papers and tissue papers, and this differentiation is based on either two or three underlying dimensions. Rough/smooth and thin/thick were the two main dimensions of surface feel found for the printing papers, whereas friction and wavelength were strongly related to the perceptual cues employed in scaling the model surfaces. These experimental results support the duplex theory of texture perception, which holds that both a “spatial sense”; used to discriminate the roughest textures from the others, and a “vibration sense”; used to discriminate among the smoother textures, are involved. The perception of what is considered rough and smooth depends on the experimental stimulus context. It is concluded that friction is important for human differentiation of surface textures below about 10 µm in surface roughness, and for larger surface textures, friction is less important or can even be neglected. The finger friction experiments also allowed the following conclusions to be drawn: (i) The interindividual variation in friction coefficients is too large to allow direct comparison; however, the trends in relative friction coefficients for a group of participants are the same. (ii) Lipids are transferred to the test surface of study, and this lowers the friction. (iii) Many of the studies point to a characteristic frequency during sliding of about 30 Hz, which is both characteristic of the resonance frequency of skin and the expected frequency associated with the fingerprints. (iv) The applied load in surface interrogation is in fact regulated in response to the friction force. The limits in tactile perception were indirectly researched by similarity scaling experiments on the model surfaces. Wrinkle wavelengths of 760 nm and 870 nm could be discriminated from untextured reference surfaces, whereas 270 nm could not. The amplitude of the wrinkles so discriminated was approximately 10 nm, suggesting that nanotechnology may well have a role to play in haptics and tactile perception.<br>Taktil perception bidrar starkt till den sammantagna upplevelsen av en produkt, men hur materials olika ytegenskaper påverkar och styr perceptionen är ännu inte helt klart. Den här avhandlingen undersöker hur många och vilka egenskaper som är viktiga när känslan mellan två ytor jämförs. Tillvägagångssättet är tvärvetenskapligt där fysikaliska mätningar kopplas ihop med perceptions mätningar där människor används som instrument. Två typer av perceptionsförsök har utförts, multidimensionell skalning där försökspersoner sätter siffror på hur lika två ytor känns, samt magnitud estimation där i stället intensiteten på specifika perceptuella storheter som t.ex. upplevt lenhet, upplevd mjukhet och upplevd strävhet bedömdes. Eftersom taktil perception innebär kontakt samt relativ rörelse mellan hud och ytor, har fokus i avhandlingen varit att undersöka hur friktion och ytans struktur (ytråhet) påverkar och bidrar till den taktila perceptionen. Förutom fysikaliska mätningar på friktion och ytstruktur har värmekonduktivitet, mjukhet samt olika standard mätningar inom pappersindustrin mätts. En metod för att mäta friktion mellan ett finger och olika ytor har utvecklats för att i möjligaste mån återspegla friktionskomponenten i upplevt taktil perception. Friktionskoefficienter beräknades och jämfördes mellan alla ytor. De stimuli som har studerats är tryckpapper och mjukpapper samt modellytor, gjorda för att systematiskt undersöka hur ytstruktur påverkar perceptionen. Tillverkningsmetoden för modellytorna valdes så att ytorna var tåliga och kunde tvättas och därmed återanvändas. Strukturen på ytorna bestod av ett vågformat mönster där våglängden varierade mellan 270 nm och 100 µm och amplituden mellan 7 nm och 6 µm. Enligt vår vetskap är det första gången som strukturer i de här skalorna har gjorts utan att samtidigt ändra andra material egenskaper. Friktionskoefficienten minskade med ökad kvot mellan amplituden och våglängden på modellytorna samt med ytråheten på tryckpappren. En analytisk modell tillämpades på kontakten mellan ett finger och ytorna som visade att friktionskoefficienten beror av den verkliga kontaktarean. För de mycket grövre mjukpappren uppmättes inga stora skillnader i friktion förmodligen för att kontakarean mellan de olika mjukpapprena var lika. Den faktiska kontakarean visade sig också vara viktig för perceptionen av lenhet, strävhet, torrhet och svalhet. Det visade sig vara en stor perceptuell skillnad mellan olika typer av tryckpapper och mjukpapper utifrån hur stimuli placerade sig på en taktil karta. För de tre materialen användes enbart två alternativt tre egenskaper hos materialet för att särskilja mellan alla olika par. För tryckpapper verkade en viktig dimension kunna beskrivas av alla de perceptuella och fysikaliska egenskaper som har med kontaktarean att göra, d.v.s. lenhet, svalhet, torrhet, ytråhet, värmekonduktivitet samt friktion. För att taktilt särskilja mellan olika ytor där bara strukturen är varierade, kunde friktion och våglängden relateras till spridningen i kartan. Båda studierna stödjer duplex theory of texture perception, där ett spatialt sinne används för att särskilja en av de grövre ytorna från en slät, och ett vibrationssinne för att särskilja mellan olika släta strukturer. Friktionen visade sig alltså vara en viktig fysikalisk egenskap för strukturer under åtminstone 10 µm i ytråhet. Från fingerfriktions mätningar kunde även följande slutsatser dras: (i) Stora skillnader i friktionskoefficient mellan olika personer uppmättes, men trenderna mellan olika individer var samma, vilket gör att relativa skillnader i friktion från en individ är representativa. (ii) Lipider (fingerfett) som överförs från fingret till ytan vid kontakt sänker friktionen. (iii) Frekvensinnehållet i friktionskraften varierar mellan olika ytor och den frekvenstopp som ses vid 30 Hz kan möjligtvis bero på fingrets struktur eller resonansfrekvensen på huden. (iv) Den pålagda kraften under en friktionsmätning visar sig omedvetet regleras av den friktionskraft som fingret möter under rörelse. Hur små strukturer som kan diskrimineras har indirekt undersökts genom likhetsförsöket på modellytorna där försökspersoner skulle bedöma hur lika alla par av ytor kändes. Resultaten visade att ytorna med våglängder på 760 nm och 870 nm upplevdes olika jämfört med referens ytor utan något systematiskt mönster, medan ytan med 270 nm i våglängd inte kunde särskiljas. Amplituden på ytan som kunde diskrimineras var endast ca 10 nm, vilket indikerar att nanoteknologi mycket väl kan bidra inom haptiken och för att i framtiden kontrollera den taktila perceptionen.<br><p>QC 20121026</p>

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Karlsson, Robin. "Improving Baked Textures as a Content Creator." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4832.

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Problems. This thesis will look at texture-baking for games and the various problems that surrounds it. The problems discussed include topics such as tangent basis synchronization and improving bakes by using methods such as cages, smoothing groups splits, etc. Motivation. The reason for looking at this is that it is an important topic in content creation for modern games. Yet people are still struggling with how to get normalmaps that are interpreted correctly in their game engine of choice and how to get clean bakes. Solution. The results is a few different methods for improving baked textures (such as proxy meshes and cages, etc.) and establishing a pipeline with tangent synchronization via Handplane. The practical results are in the end presented by some comparison images with comparisons for model that do and don’t use the techniques discussed herein. The pipeline created in the thesis has the potential to improve the generation of baked textures in a way so that they will render better in real-time applications. Methodology. The results were established by basing it upon baking experiences regarding baking and texturing models for real-time applications. The experiments were set up so that the I would revisit older, somewhat complex models and try to improve their baking. There were also a comparison of applications that were compared by trying to generate noise-less ambient occlusion textures.<br>En uppsats som handlar om hur man som grafiker till spel och/eller film kan förbättra bakade texturer som exempelvis normal och ambient occlusion texturer.

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Seck, Alassane. "3D surface texture analysis of high resolution normal fields for facial skin condition assessment." Thesis, Aberystwyth University, 2016. http://hdl.handle.net/2160/d3544edf-bcd2-4af1-85af-f125cba675f7.

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In this thesis, we introduce new methods for analysing three dimensional surface texture using high resolution normal fields and apply these to the detection and assessment of skin conditions in human faces, specifically wrinkles, pores and acne. The thesis is part of a project sponsored by Unilever with an interest in applying the outcome of the research to facial skin care product development. This explains our focus on facial skin conditions. The main contributions of this thesis are the introduction of three methods of extracting texture descriptors from high resolution surface orientation fields, a comparative study of two-dimensional and three-dimensional skin texture analysis and the collection of an extensive dataset of high resolution 3D facial scans presenting various skin conditions. The dataset includes human rating judgements on the presence of certain skin conditions. Computer aided skin condition assessment has been mostly addressed using two dimensional texture analysis techniques on skin images or coarse geometrical features extracted from the skin’s three dimensional macro structures. While the first trend ignores the three dimensional nature characterising most of the skin conditions, the latter mainly deals with geometrical features that are not fine enough to capture skin structures at the meso and micro scales. Advances in three dimensional surface imaging during the last few decades brings the possibility of capturing human skin’s fine geometrical structures and re- flectance properties with unprecedented quality and resolution (down to the level ii of the pores). The methods proposed in this work aim at leveraging these advances and revisit the formulation of texture analysis as a three dimensional problem. For data collection we set up a Lightstage to capture high resolution facial normal fields along with reflectance properties. The collected data are photo-realistically rendered and presented to the general public for annotations indicating the presence of the studied skin conditions. These constitute the ground truth on which we apply the proposed methods and learn models for detecting and assessing facial skin conditions. We also demonstrate that some of these three dimensional surface texture descriptors can be extended to synthesize highly detailed skin structures and simulate the studied skin condition on normal faces.

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Bittner, Jason P. "The use of texture in improving the simulation of low-level flight." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29362.pdf.

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Orme, Brian J. "Improving Fat Retention and Texture in Low-Moisture Cheese Manufactured from Ultrafiltered Milk." DigitalCommons@USU, 1998. https://digitalcommons.usu.edu/etd/5453.

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Three serious problems have been experienced in the manufacture of low moisture cheese using ultrafiltration (UF)- high fat-loss, excessive moisture retention, and poor cheese texture. In this work the causes of these problems were identified, and means of overcoming them were developed. Coagulation and cheese-making experiments indicated that UF concentration of milk shifts the control of rennet coagulation toward the casein micelle collision rate and away from rennet activity, resulting in formation of a rough-textured curd structure that resists syneresis. Use of 4x whole milk retentate, instead of 5x, improved rennet curd structure, syneresis, and UF cheese texture without reducing protein retention in the cheese. Use of increased rennet and reduced set temperature (26°C) also improved curd structure, syneresis, and cheese texture. Washing of the rennet curd prepared from 4x milk retentate during cheese-making, instead of diafiltration of retentate, was found to improve cheese texture, and cheese moisture below 39% was achieved. UF retentate was inconsistent as a starter medium because it offered no protection against bacteriophage proliferation, and the growth of some strains of Lactococcus lactis was impaired in UF retentate. Commercial, internally-buffered pH-controlled starter media were more consistent than fermented retentate starter when used for making cheese from 4x retentate. Low-pressure homogenization of milk at a temperature between 37°C and 45°C increased fat recovery in UF cheese made from 4x ultrafiltration concentrated milk with minimal damage to cheese texture and syneresis. A procedure was developed for the manufacture of quality, high-yield, low-moisture cheese from 4 times ultrafiltration concentrated whole milk. Fat retention in the cheese was 95% and protein retention was 85%

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Aldridge, Roger Benjamin Lochore. "Dermato-informatic approaches to understanding and improving lesional diagnostic expertise in cutaneous oncology." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31068.

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Cutaneous malignancies represent a quarter of all new cancer diagnoses in the UK. The key to reducing the tumours’ associated mortality and morbidity is early diagnosis and treatment. Prompt diagnosis remains predominately a clinical skill, but relatively little investigation of the cognitive psychology underpinning expertise in this domain has been undertaken. This thesis aims to improve understanding of these processes and investigate how lesional diagnostic expertise might be enhanced. A large database of diagnostically tagged images was captured specifically for this project. A series of separate studies were undertaken to give insight into how lesional diagnosis occurs and how it can be improved. The studies highlighted that non-analytical pattern recognition (NAPR) is likely to predominate in distinguishing malignant and non-malignant skin lesions and that the widely-promoted rules advocating analytical pattern recognition (APR) are not effective for discriminating melanoma from benign pigmented lesions. The keystone to promoting the development of NAPR and thus diagnostic expertise would seem to be increasing a novice’s personal library of examples with relevant feedback. Studies demonstrated that current undergraduate exposure was variable but universally sparse, so simulation by way of diagnostically tagged images was developed which showed accuracy could be improved by increased exposure. This improvement occurred in both a content specific and dose responsive manner. These studies also highlighted that the learning curves for skin lesions are not uniform. Further studies demonstrated that the choice of images had implications on the development of diagnostic expertise; suggesting it was important that these images represent clinical practice rather than “classic” examples traditionally advocated for teaching purposes. In addition, studies highlighted the potential benefit of the 3D models developed during this project. Building on the idea that a personal catalogue of relevant referent images was crucial to enhanced diagnostic accuracy, prototype software was developed to exteriorise the experts’ library of examples; in the tests described novices utilising the software delivered superior accuracy than medical students on the completion of their undergraduate teaching. In summation, the work described shows that by utilising dermato-informatic approaches lesional diagnostic competence can be improved significantly.

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Montgomery, Dean. "Improving radiotherapy using image analysis and machine learning." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/23554.

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With ever increasing advancements in imaging, there is an increasing abundance of images being acquired in the clinical environment. However, this increase in information can be a burden as well as a blessing as it may require significant amounts of time to interpret the information contained in these images. Computer assisted evaluation is one way in which better use could be made of these images. This thesis presents the combination of texture analysis of images acquired during the treatment of cancer with machine learning in order to improve radiotherapy. The first application is to the prediction of radiation induced pneumonitis. In 13- 37% of cases, lung cancer patients treated with radiotherapy develop radiation induced lung disease, such as radiation induced pneumonitis. Three dimensional texture analysis, combined with patient-specific clinical parameters, were used to compute unique features. On radiotherapy planning CT data of 57 patients, (14 symptomatic, 43 asymptomatic), a Support Vector Machine (SVM) obtained an area under the receiver operator curve (AUROC) of 0.873 with sensitivity, specificity and accuracy of 92%, 72% and 87% respectively. Furthermore, it was demonstrated that a Decision Tree classifier was capable of a similar level of performance using sub-regions of the lung volume. The second application is related to prostate cancer identification. T2 MRI scans are used in the diagnosis of prostate cancer and in the identification of the primary cancer within the prostate gland. The manual identification of the cancer relies on the assessment of multiple scans and the integration of clinical information by a clinician. This requires considerable experience and time. As MRI becomes more integrated within the radiotherapy work flow and as adaptive radiotherapy (where the treatment plan is modified based on multi-modality image information acquired during or between RT fractions) develops it is timely to develop automatic segmentation techniques for reliably identifying cancerous regions. In this work a number of texture features were coupled with a supervised learning model for the automatic segmentation of the main cancerous focus in the prostate - the focal lesion. A mean AUROC of 0.713 was demonstrated with 10-fold stratified cross validation strategy on an aggregate data set. On a leave one case out basis a mean AUROC of 0.60 was achieved which resulted in a mean DICE coefficient of 0.710. These results showed that is was possible to delineate the focal lesion in the majority (11) of the 14 cases used in the study.

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Bangs, Corey F. "Improving Identification of Area Targets by Integrated Analysis of Hyperspectral Data and Extracted Texture Features." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/17317.

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Approved for public release; distribution is unlimited<br>Hyperspectral data were assessed to determine the effect of integrating spectral data and extracted texture features on classification accuracy. Four separate spectral ranges (hundreds of spectral bands total) were used from the VNIR-SWIR portion of the electromagnetic spectrum. Haralick texture features (contrast, entropy, and correlation) were extracted from the average grey level image for each range. A maximum likelihood classifier was trained using a set of ground truth ROIs and applied separately to the spectral data, texture data, and a fused dataset containing both types. Classification accuracy was measured by comparison of results to a separate verification set of ROIs. Analysis indicates that the spectral range used to extract the texture features has a significant effect on the classification accuracy. This result applies to texture-only classifications as well as the classification of integrated spectral and texture data sets. Overall classification improvement for the integrated data sets was near 1per cent. Individual improvement of the Urban class alone showed approximately 9 per cent accuracy increase from spectral-only classification to integrated spectral and texture classification. This research demonstrates the effectiveness of texture features for more accurate analysis of hyperspectral data and the importance of selecting the correct spectral range used to extract these features.

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Whitbread, P. J. "Multi-spectral texture : improving classification of multi-spectral images by the integration of spatial information /." Title page, abstract and contents only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phw5792.pdf.

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Thesis (Ph. D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1994?<br>One computer disk in pocket inside back cover. System requirements for accompanying computer disk: Macintosh computer. Includes bibliographical references (leaves 148-160).

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Brooks, Jill. "An RCT to determine an effective skin regime aimed at improving skin barrier function and quality of life in those with podoconiosis in Ethiopia." Thesis, University of Hull, 2016. http://hydra.hull.ac.uk/resources/hull:13621.

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Podoconiosis is a neglected tropical skin disease caused by a fault in skin barrier function (SBF) combined with a genetic predisposition. Irritant minerals and pathogens entering breaches in plantar skin cause an inflammatory reaction and lower leg lymphoedema. This has a considerable negative impact on the quality of life and economic status of some of the poorest people in 20 countries. Podoconiosis is preventable and treatable but not curable. No previous pre/post controlled intervention studies on skin treatment for the disease have been published. The aim of this randomised control trial (RCT) was to evaluate the effectiveness of a low-cost evidence-based skin care intervention to improve the SBF in the legs/feet and enhance disease related quality of life. A pilot study (n=10) indicated that adding 2% glycerine to the existing skin management regime used in Ethiopia could have a positive effect on stratum corneum (SC) hydration levels and trans-epidermal water loss (TEWL). The study recruited participants from two Ethiopian clinics (n=193). The control group used the existing treatment regime: washing legs/feet with soap, soaking in 6 litres of water with disinfectant added and applying Vaseline®. The experimental group added a 2% dilution of glycerine to 1/6 of the amount of soaking water and 0.0045% less disinfectant. After 3 months the experimental intervention had a highly significant positive effect on TEWL (p = < 0.001) and SC hydration (p = < 0.002) compared to the control. The reduction in foot circumference was highly significant (p = < 0.001). There was no significant group difference in Dermatology Life Quality Index (p = 0.907). The study indicates the very positive effect on SBF of adding 2% glycerine and less disinfectant to the current treatment. This finding offers a significant contribution to the body of knowledge on the management of the disease. The addition of 2% glycerine to treatment regimens may also have positive effects on other skin diseases with compromised SBF.

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Nun, Nicholas. "Improving Skin Wound Healing Using Functional Electrospun Wound Dressings and 3D Printed Tissue Engineering Constructs." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1617985844538101.

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Chiu, Chun-hung, and 趙俊雄. "The role of dynamic cooling in improving clinical efficacy during pulsed dye laser treatment of port wine stain in Chinese." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B26661482.

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Rush, Allison K. "Improving the Mechanistic Understanding of Zinc Pyrithione Bioavailability in Skin through Lateral and Transverse Diffusion Measurements." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439281238.

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Bobjer, Olle. "Friction and discomfort in the design and use of hand tools : exposure to textures at different loads and velocities with reference to contamination." Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/14755.

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The skin of the palm of the hand has no friction. It is only when in contact with other objects that frictional forces appear. This friction does not, however, conform to the classic laws of friction. The thesis shows that static skin friction is lower than dynamic friction, and that increased velocity increases the coefficient of friction, but increasing load reduces it. Consequently, references to coefficient of friction where palm skin is one of the friction partners require velocity, surface pressure and skin conditions to be specified in addition to contaminants in the friction interface, before reliable conclusions can be drawn. Eleven textured and one non-textured samples all made from the same material were investigated using eighteen male subjects. They were exposed to five contaminants, three skin conditions, three levels ofload and velocities in the range 2-128 mm/so It was concluded that velocity in the friction interface is the most dominant factor contributing to palm friction. Only small, non-significant, differences in friction were found between different types of textures under non-contaminated conditions, but major, and significant differences were observed under contaminated conditions. Coarse textures increased discomfort. For static- and dynamic friction the type of texture, coarse or fine, will affect friction in different ways depending on the skin conditions being "clean" or "contaminated." Experiments show that coarse textures generate less friction than fine under the clean conditions. Under contaminated conditions however coarse textures generate more friction than fine. The highest coefficient offriction 1-1=2.22 (SO=1.12) was recorded under dynamic conditions for a clean hand on a non-textured surface when the surface pressure was low - 6.3 kPa (SO 2.1). The lowest coefficient offriction 1-1=0.05 (SO=0.03) was found under static conditions, with lard present on a non-textured surface when the surface pressure was high - 81.4 kPa (SO=31.0). Two regression models were developed. Regression coefficients are presented for surface topography variables as well as skin condition and contamination, velocity surface pressure and discomfort. Two new surface topography representations explain the generation of friction forces. The uppermost 5% of the volume of texture peaks provided significant information for transfer offriction forces.

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Paton, Elizabeth Jane. "Experiences in improving membership engagement and grant success for clinical research networks in particular for the Australian melanoma and skin cancer community." Thesis, The University of Sydney, 2021. https://hdl.handle.net/2123/27778.

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Introduction The purpose of the thesis is to investigate the important role of clinical trial networks (CTNs), specifically the national cancer cooperative trial groups (CCTGs), have in growing high-quality memberships and optimising grant success to support the undertaking of a greater number of investigator-initiated, high-quality, Australian-led, skin cancer clinical trials. This is critically important in Australia which has the highest skin cancer burden globally. Methodology Experiences from CTNs with a particular focus on the skin CCTG have been evaluated. Two studies have been undertaken. Results The essay comprises four chapters that deals with CTN function including membership optimisation and grant application success. Significant underlying themes were found. CTNs need: • to have strong leadership, clear vision and robust governance; • to be supported as they mature and reorganise; • to build a strong culture which can enhance members’ commitment to the cause; • to use resources wisely; • to facilitate appropriate communications with and across all stakeholders when conducting RCTs; • to encourage membership diversity and research participation; and • to encourage their members to have a flexible mindset to optimise research success. Conclusions The thesis provides a significant resource for the CTN and CCTG community. The studies led to significant advances in the national capacity to support an international membership which is capable of securing funding to complete high-quality, Australian-led, investigator-initiated skin cancer research. The thesis demonstrates that a dedicated skin CCTG has a real place globally. The thesis provides a platform for further research in improving CTN function, reducing trial failure and improvements translating results to impact on community practice.

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Radka, Tina. "Improving the efficiency of aminolevulinate-photodynamic therapy of skin cells by combining UVA irradiation and potent iron chelating agents." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642023.

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Photodynamic therapy (PDT) is widely used for the treatment of skin cancer. Mechanistically, in delta-aminolevulinic acid (ALA)-mediated PDT, the addition of ALA to cells bypasses the negative feedback control of heme biosynthesis, leading to accumulation of photosensitizing concentrations of protoporphyrin IX (PPIX). Subsequent activation of cellular PPIX with an external light source (usually red light, 550-750 nm) leads to generation of reactive oxygen species (ROS), resulting in cell death. The major side effect of ALA-PDT treatment is the pain experienced by patients. Management of treatment-related pain still remains a considerable challenge in patients. Further optimization of the treatment protocol including light source, dose and duration therefore seems crucial to try and address this issue. To improve the efficiency of ALA-PDT of skin cells in the present study three approaches were used: (i) The conventional light source was changed to UVA (320-400 nm) that is absorbed more efficiently by PPIX and is 40-fold more potent in killing cultured skin cells than red light; (ii) ALA treatment was combined with the potent iron chelators, salicylaldehyde isonicotinoyl hydrazone (SIH), pyridoxal isonicotinoyl hydrazone (PIH) or desferrioxamine (DFO) to further increase the accumulation of PPIX through the depletion of iron available for ferrochelatase-mediated bioconversion of PPIX to heme; (iii) ALA treatment was combined with UVA-activatable caged iron chelators (CICs) that do not chelate iron unless activated by UVA. The CICs used were aminocinnamoyl-based SIH derivatives, ‘BY123’ and ‘BY128’. Upon activation by UVA, these CICs release the active SIH allowing for specific localised release of iron chelator in the cells. Spontaneously immortalised HaCaT cell line and Met2 cancer line (squamous cell carcinoma) were used as cell models. Cells were pre-treated (or not) for 18 h with SIH, PIH or DFO (20-100 µM), then subjected to ALA (0.5 mM) for 2 h and irradiated with low doses of UVA (5-50 kJ/m2). The quantification of intracellular PPIX was carried out by both HPLC and spectrofluorimetry after treatments of cells with ALA alone or combined with chelators. Cell death was examined 24 h after UVA exposure of ALA+/-chelators-treated cells by flow cytometry using Annexin V-propidium iodide dual staining assay. Pretreatment of HaCaT cells with ALA caused a substantial increase in the intracellular levels of PPIX which in turn sensitized the cells to very low non-cytotoxic UVA doses. Pre-treatment with DFO, PIH and SIH followed by ALA treatment further enhanced the PPIX level in HaCaT cells and caused an additional level of photosensitization to low UVA doses. Among the chelators used, SIH combined with ALA provided the most efficient increase in PPIX and cell killing following UVA irradiation, even at a lower SIH concentration of 20 µM. Among the CICs used, both UVA-activated BY123 and BY128 were as effective as SIH in increasing the level of PPIX and cell killing in ALA-treated cells following exposure to low doses of UVA. UVA-based ALA-PDT combined with SIH (or its caged-derivatives BY123 and BY128) appears therefore to be a promising modality for topical PDT. The high lipophilicity of SIH (and its caged-derivatives) which facilitates skin penetration and their potent cytotoxicity at low UVA doses should therefore allow the current modality for topical PDT to be improved, through a reduction of the time of irradiation and therefore the duration of pain experienced during the treatment. The use of SIH-based CICs will be a safer alternative to topical ALA-PDT than ‘naked’ SIH, as application of these pro-chelators will substantially decrease the exposure of the surrounding normal skin tissue to strong iron chelators and their toxic side effects.

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Matour, Soha. "A new design for double skin facade in warm climates: Improving thermal performance and natural ventilation of the system." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/231909/1/Soha_Matour_Thesis.pdf.

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This thesis contributes to the improvement of Double Skin facades' thermal performance in warm climates. A new design for DSF was proposed and evaluated using an experimental study on a scaled model and Computational Fluid Dynamics simulations. The proposed facade named IS-DSF (Interstitial slat-blind DSF) showed the capability to reduce overheating risk in the cavity due to two applied strategies: shading devices’ specific placement and wind-induced ventilation improvement. Finally, a framework was developed for the implementation of IS-DSF in warm climates applicable at the early stage of building design.

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Julian, Pauline. "Méthodes variationnelles pour la segmentation avec application à la réalité augmentée." Phd thesis, Toulouse, INPT, 2012. http://oatao.univ-toulouse.fr/17822/7/Julian_P.pdf.

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Dans cette thèse, nous nous intéressons au problème de la segmentation de portraits numériques. Nous appelons portrait numérique la photographie d’une personne avec un cadre allant grossièrement du gros plan au plan poitrine. Le problème abordé dans ce travail est un cas spécifique de la segmentation d’images où il s’agit notamment de définir précisément la frontière de la région « cheveux ». Ce problème est par essence très délicat car les attributs de la région « cheveux » (géométrie, couleur, texture) présentent une grande variabilité à la fois entre les personnes et au sein de la région. Notre cadre applicatif est un système d’« essayage virtuel » de lunettes à destination du grand public, il n’est pas possible de contrôler les conditions de prise de vue comme l’éclairage de la scène ou la résolution des images, ce qui accroît encore la diculté du problème. L’approche proposée pour la segmentation de portraits numériques est une approche du plus grossier au plus fin procédant par étapes successives. Nous formulons le problème comme celui d’une segmentation multi-régions, en introduisant comme « régions secondaires », les régions adjacentes à la région « cheveux » , c.-à-d. les régions « peau » et « fond ». La méthode est fondée sur l’apparence (appearance-based method) et a comme spécificité le fait de déterminer les descripteurs de régions les plus adaptés à partir d’une base d’images d’apprentissage et d’outils statistiques. À la première étape de la méthode, nous utilisons l’information contextuelle d’un portrait numérique — connaissances a priori sur les relations spatiales entre régions— pour obtenir des échantillons des régions « cheveux », « peau » et « fond ». L’intérêt d’une approche fondée sur l’apparence est de pouvoir s’adapter à la fois aux conditions de prises de vue ainsi qu’aux attributs de chaque régions. Au cours de cette étape, nous privilégions les modèles de forme polygonaux couplés aux contours actifs pour assurer la robustesse du modèle. Lors de la seconde étape, à partir des échantillons détectés à l’étape précédente, nous introduisons un descripteur prenant en compte l’information de couleur et de texture. Nous proposons une segmentation grossière par classification en nous appuyant à nouveau sur l’information contextuelle : locale d’une part grâce aux champs de Markov, globale d’autre part grâce à un modèle a priori de segmentation obtenu par apprentissage qui permet de rendre les résultats plus robustes. La troisième étape ane les résultats en définissant la frontière des « cheveux » comme une région de transition. Cette dernière contient les pixels dont l’apparence provient du mélange de contributions de deux régions (« cheveux »et « peau » ou «fond »). Ces deux régions de transition sont post-traitées par un algorithme de «démélange » (digital matting) pour estimer les coecients de transparence entre « cheveux » et « peau », et entre « cheveux » et « fond ». À l’issue de ces trois étapes, nous obtenons une segmentation précise d’un portrait numérique en trois « calques », contenant en chaque pixel l’information de transparence entre les régions « cheveux », « peau » et « fond ». Les résultats obtenus sur une base d’images de portraits numériques ont mis en évidence les bonnes performances de notre méthode.

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Lacampagne, Soizic. "Localisation et caractérisation des tannins dans la pellicule du raisin : impact de l'organisation physico-chimique des parois cellulaires sur la composante tannique, la qualité du fruit et la typicité des raisins de Bordeaux." Thesis, Bordeaux 2, 2010. http://www.theses.fr/2010BOR21762/document.

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Qualité du fruit et la typicité des raisins de Bordeaux.La maturation de la pellicule du raisin est un phénomène complexe, caractérisé par de nombreux changements structuraux importants et par l’accumulation de composés œnologiques tels que les tannins. Malgré leurs propriétés biologiques et organoleptiques essentielles pour la qualité des fruits et des vins, peu de travaux concernent l’organisation et la localisation de ces composés au sein du tissu pelliculaire. Dans la pellicule, les tannins peuvent être plus ou moins liés aux constituants cellulaires modulant ainsi leur extractibilité lors des processus de vinification. Notre travail, basé sur des approches biochimiques, moléculaires et microscopiques, apporte des données nouvelles sur la biosynthèse, la localisation et l’organisation des tannins dans la pellicule. Au sein de ce tissu, nous avons souligné l’importance des tannins pariétaux et montré que leurs caractéristiques physico-chimiques dépendaient entre autre des changements structuraux des parois. Ainsi, cette organisation caractérise en partie la texture de la pellicule et conditionne la qualité du fruit. Pour appréhender l’évolution des critères de texture de la pellicule au cours de la maturation du raisin, l’analyse sensorielle des baies et la mesure par pénétrométrie s’avèrent être des outils pertinents<br>Skin grape maturation is a complex phenomenon, characterized by an important number of structural changes as well as by phenolic compounds accumulation (i.e. tannins). Despite their biological and organoleptic properties in fruit and wine quality, few studies report both tannins organization and localization in skin tissue. In skins, tannins may be more or less related with cellular components, modulating their extractability during winemaking process.Our work, based on biochemical, molecular and microscopic approaches reveals new data on skin tannins biosynthesis, localization and organization. Within this tissue, we highlighted the parietal tannins importance, we evidenced that their physicochemical characteristics depend among other structural changes on cell walls. Thus, this organization partially characterized the skin texture and affects fruit quality. To understand the evolution criteria for skin texture during grape berry ripening, sensory analysis and measurements by penetrometer proved to be relevant tools

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Löw, Marjorie. ""Mecanismos de desenvolvimento de textura durante a recristalização primária de aços ferríticos por difração de Raio-X e difração de Elétrons retroespalhados"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-06062007-161839/.

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A difração de raios X e de elétrons retroespalhados, em escalas distintas, foram aplicadas para acompanhar mudanças microestruturais em dois aços ferríticos baixo carbono (2%Si e ABNT 1006), observando-se o desenvolvimento da textura nas etapas de laminação a frio (skin-pass) e recozimento a 760 oC. Para ambos os aços, os resultados permitiram afirmar que o fenômeno que ocorre após a laminação por skin-pass e tratamento térmico, nas condições deste trabalho, é a recristalização primária. A aplicação do skin-pass criou mais discordâncias em grãos com baixo fator de Taylor por sofrerem mais deformações. Observou-se a nucleação e crescimento de grãos em regiões de grande densidade de células de discordâncias. A presença do silício atrasou a recuperação favorecendo o aumento de subcontornos. Não foi observado o crescimento anormal de grãos, nem em função da presença de grãos Goss. Os contornos CSL não garantiram o crescimento do grão. Núcleos de crescimento de grãos deram origem a grãos com orientações distintas, indicando que o crescimento de grãos não dependeu da existência prévia de grãos com as orientações desenvolvidas, demonstrando que o crescimento anormal de grãos não está relacionado necessariamente com os grãos Goss.<br>X ray and electron backscattering diffraction, in distinct levels, were applied to evaluate microstructural changes in two low carbon ferritic steels (2%Si and ABNT 1006), observing the texture development in cold lamination step (skin-pass) and in the subsequent annealing at 760 oC. In these two steels, results showed that after the skin-pass and annealing in the conditions of the present work, the observed phenomenon is the primary recrystallization. By applying skin-pass dislocations were introduced mostly in low Taylor factor grains as they are prone to be more deformed. Nucleation and grain growth were observed in high density dislocation cell regions. Silicon presence delayed the recovery favoring the sub-boundaries increase. It was not observed the abnormal grain growth, even in the presence of Gross grains. CSL boundaries did not guarantee the grains growth. Growing nuclei gave rise to grains with distinct orientations, showing that the grain growth was not dependent on the previous presence of grains with the developed orientation. This fact demonstrates that the abnormal grain growth is not necessarily related to the Gross grains.

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Pilipenco, Alina. "Vliv tenzidů a kosmetických polysacharidů na parametry pleti a její mikrobiom." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-414136.

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The aim of this diploma thesis was to investigate the effect of surfactants and cosmetic polysaccharides on skin parameters and its microbiome. Three surfactants were tested to determine their effect: Sodium Dodecyl Sulfate (SDS), Cocamidopropyl Betaine (CAPB), Decylglucoside (DG). Distilled water was also used for comparison. For the next part of the experimental work were selected 6 polysaccharides: high molecular weight Hyaluronic Acid (HMW HA), very low molecular weight Hyaluronic Acid (VLMW HA), Sodium Caproyl Hyaluronate (CaproylHA), Sodium Carboxymethyl -Glucan (NaCMG), Schizophyllan and Glucomannan. For comparison, placebo and untreated control (only CAPB treatment) were also included in the tests. The first part of the work is a literature search on the assigned topic, which contains the following parts: skin anatomy and its biophysical properties, skin microbiome and its functions, description of used surfactants and polysaccharides. The experimental part is mainly focused on bioengineering methods for evaluation of skin parameters and qRT-PCR to determine the relative proportion of main bacterial species of skin microbiome. First, the effect on the CT gene of 16S rDNA was analysed, and Propionibacterium acnes and Staphylococcus epidermidis strains were selected for further analysis. In conclusion are presented an overview of all properties of selected substances and assessment of their application in cosmetics.

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Tremblay, Clifford Allen. "Two Screens and an Urban Place." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/33120.

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An exploration to utilize the notion of a screen in order to orchestrate an urban response, an urban mixed-use building. It is an investigation into the contradictions of materiality and the inherent values of organistic and rigid geometries and formations in terms of architecture and the facade. Two screens make use of pattern, texture, and layering to create a sense of order and chaos within the same instance. This is most noticeable through the introduction of light, natural and artificial. These screens are a reflection of the ripples, webs, and vibrations of all human activity. This is an investigation into repetition and layering, covering and wrapping, and ultimately creating an enjoyable environment to live, work, and play. The program is quite simple. On the ground floor there is a grocery store, shops, and offices. On the upper levels, there are townhomes and apartments, one and two bedroom.<br>Master of Architecture

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Aldeeb, Nader H. [Verfasser], Olaf [Akademischer Betreuer] Hellwich, Olaf [Gutachter] Hellwich, Stefan [Gutachter] Hinz, and Franz [Gutachter] Rottensteiner. "Analyzing and improving image-based 3D surface reconstruction challenged by weak texture or low illumination / Nader H. Aldeeb ; Gutachter: Olaf Hellwich, Stefan Hinz, Franz Rottensteiner ; Betreuer: Olaf Hellwich." Berlin : Technische Universität Berlin, 2020. http://d-nb.info/1223537307/34.

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Casati, João Paulo Brognoni. "Método para segmentação de pele humana em imagens faciais baseado em informações de cor e textura." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-30012014-152011/.

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A segmentação de pele em imagens é um importante processo para uma vasta gama de aplicações, como detecção e rastreamento de faces, reconhecimento de gestos, computação forense, entre outros. Um dos maiores problemas encontrados neste tipo de aplicação é a presença de objetos que possuem cor de pele nas imagens, mas não fazem parte de segmentos reais de pele, sendo muitas vezes erroneamente classificados como pele. A fim de reduzir a frequência destes falsos positivos, é apresentado neste trabalho um método de segmentação de pele humana em imagens faciais que possui duas diferentes etapas que reduzem a quantidade de falsos positivos do processo sem que se percam quantidades significantes de verdadeiros positivos. Estas duas etapas são chamadas de FPAR (False Positive Area Reduction) e aplicação de textura. A primeira visa remover segmentos não contínuos classificados como pele e a segunda aborda a aplicação de textura nas imagens, removendo áreas em que a textura não se assemelha à textura de pele humana. Para isto, foi desenvolvido o banco de imagens SFA (Skin of FERET and AR), constituído de imagens originais dos bancos de faces FERET e AR, seus respectivos ground truths de segmentação de pele e amostras de pele e não pele extraídas das imagens originais. O método apresentado neste trabalho apresenta resultados promissores atingindo até 46,9% de redução de falsos positivos sem que a acurácia aferida tenha redução significante (apenas 1,8%). Este trabalho tem como contribuições o método desenvolvido e o banco de imagens SFA que fica disponível online para download pela comunidade científica.<br>Skin segmentation is an important process for many kinds of application like face detection, face tracking, gesture recognition, forensic computing and others. One of the main problems found in this kind of application is the presence of objects which have skin color but are not part of actual skin segments, being wrongly classified as skin. Aiming to reduce the frequency of these false positives, this work presents a method of human skin segmentation in facial images which has two different steps that reduces the false positives without losing significant areas of true positives. These two steps are called FPAR (False Positive Area Reduction) and texture application. The first one removes segments classified as skin which are not continuous and the second one is an analysis of the image texture, removing areas which the texture is not alike human skin texture. To achieve this, the SFA (Skin of FERET and AR) image database was developed, constituted of original images retrieved from AR and FERET face databases, their respective ground truths of skin segmentation and skin and non-skin samples retrieved from the original images. The method presented in this work shows promising results, reaching up to 46.9% of false positive reduction without significant reduction of the accuracy (1.8%). This work has as contributions the developed method and the SFA database, which is available for download for scientific community.

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Medeiros, Rafael Sachett. "Detecção de pele humana utilizando modelos estocásticos multi-escala de textura." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/70193.

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A detecção de gestos é uma etapa importante em aplicações de interação humanocomputador. Se a mão do usuário é detectada com precisão, tanto a análise quanto o reconhecimento do gesto de mão se tornam mais simples e confiáveis. Neste trabalho, descrevemos um novo método para detecção de pele humana, destinada a ser empregada como uma etapa de pré-processamento para segmentação de gestos de mão em sistemas que visam o seu reconhecimento. Primeiramente, treinamos os modelos de cor e textura de pele (material a ser identificado) a partir de um conjunto de treinamento formado por imagens de pele. Nessa etapa, construímos um modelo de mistura de Gaussianas (GMM), para determinar os tons de cor da pele e um dicionário de textons, para textura de pele. Em seguida, introduzimos um estratégia de fusão estocástica de regiões de texturas, para determinar todos os segmentos de diferentes materiais presentes na imagem (cada um associado a uma textura). Tendo obtido todas as regiões, cada segmento encontrado é classificado com base nos modelos de cor de pele (GMM) e textura de pele (dicionário de textons). Para testar o desempenho do algoritmo desenvolvido realizamos experimentos com o conjunto de imagens SDC, projetado especialmente para esse tipo de avaliação (detecção de pele humana). Comparado com outras técnicas do estado-daarte em segmentação de pele humana disponíveis na literatura, os resultados obtidos em nossos experimentos mostram que a abordagem aqui proposta é resistente às variações de cor e iluminação decorrentes de diferentes tons de pele (etnia do usuário), assim como de mudanças de pose da mão, mantendo sua capacidade de discriminar pele humana de outros materiais altamente texturizados presentes na imagem.<br>Gesture detection is an important task in human-computer interaction applications. If the hand of the user is precisely detected, both analysis and recognition of hand gesture become more simple and reliable. This work describes a new method for human skin detection, used as a pre-processing stage for hand gesture segmentation in recognition systems. First, we obtain the models of color and texture of human skin (material to be identified) from a training set consisting of skin images. At this stage, we build a Gaussian mixture model (GMM) for identifying skin color tones and a dictionary of textons for skin texture. Then, we introduce a stochastic region merging strategy, to determine all segments of different materials present in the image (each associated with a texture). Once the texture regions are obtained, each segment is classified based on skin color (GMM) and skin texture (dictionary of textons) model. To verify the performance of the developed algorithm, we perform experiments on the SDC database, specially designed for this kind of evaluation (human skin detection). Also, compared with other state-ofthe- art skin segmentation techniques, the results obtained in our experiments show that the proposed approach is robust to color and illumination variations arising from different skin tones (ethnicity of the user) as well as changes of pose, while keeping its ability for discriminating human skin from other highly textured background materials.

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Ahmed, Refat Maggi. "Improving the Success of Melanocyte Keratinocyte Transplantation Surgery in Vitiligo; The Role of JAK Inhibitors, and Ablative Laser Resurfacing." eScholarship@UMMS, 2021. https://escholarship.umassmed.edu/gsbs_diss/1143.

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The Melanocyte Keratinocyte Transplantation Procedure (MKTP) is an effective surgical replacement of lost melanocytes in recalcitrant vitiligo and pigmentary skin disorders. However, it is only effective in stable vitiligo lesions because active autoimmunity destroys the newly transplanted melanocytes. Despite careful selection of candidates based on the reported clinical stability, the success of the procedure is still unpredictable. MKTP candidates with non-segmental, segmental, and mixed vitiligo, as well as hypopigmented scars and Piebaldism patients were enrolled to our studies. Our aim was first, to investigate the possible immunological mechanisms responsible for the unpredictable post- transplantation outcomes, including T cell subsets and inflammatory chemokines, by correlating these biomarkers with clinical phenotypes, duration of stability, and surgical outcomes. We used suction blister biopsy, a minimally invasive technique that we developed to sample human skin. Moreover, we quantified transplanted melanocytes in the suspension using flow cytometry. Following MKTP, we corelated these biomarkers to the repigmentation score. We found that CD8+ T cells remain in some clinically stable vitiligo lesions, correlate negatively with the post-surgical score of repigmentation, and inversely impact the durability of the responses. Interestingly, the number of transplanted melanocytes in the suspension and the duration of stability do not have prognostic roles. Based on our findings and in a second group of patients, we suppressed the activity of T cells to enhance the outcomes of MKTP. We used Ruxolitinib, JAK1/2 inhibitor, in a triple blinded randomized controlled within subject study, in comparison with Tacrolimus (a calcineurin inhibitor and the standard of care treatment in vitiligo) as well as placebo control. We found lower T cell infiltrate, lower chemokines, and better skin repigmentation in lesions treated with MKTP plus Ruxolitinib or Tacrolimus than in lesions treated with MKTP plus placebo. Lastly, we compared two different types of laser in preparation of the recipient skin for MKTP - ablative versus fractional Er:YAG laser. We found that the ablative laser is combined with minimal CD8+ T cell epidermal infiltrate and superior repigmentation score in comparison to more infiltrate and lower repigmentation score with the fractional laser. Taken together, these results from our studies provide novel insight to predict the optimal surgical candidates and will improve surgical outcomes. It advances the treatment of vitiligo by uncovering the impact of autoimmunity on the success of repigmentation and discovering new approaches to optimize the surgical treatment options in patients with vitiligo and pigmentary skin disorders.

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Chang, Ken-Mei, and 張艮媚. "Studies on Texture-Improving for Packed Tofu." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/76333535330102532072.

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碩士<br>國立嘉義大學<br>食品科學系碩士班<br>92<br>There are many defects in quality of packed tofu to be overcome, such as somewhat firm and non-uniform texture, high syneresis and weak soup-absorbing ability during cooking. The studies were conducted at two stages. First, to forge the texture of packed tofu from non-uniform to uniform state, and followed by experiment carried out to improve texture and soup-absorbing ability of packed tofu. At the first stage, 0.3 % ( w/w ) glucono-δ-lactone combined respectively with three concentrations, 0.025, 0.05 and 0.1 % ( w/w ) of magnesium chloride used to solve the problem of non-uniform texture of packed tofu. At the second stage, three processing factors, the amounts of sodium bicarbonate, baking powder and curdlan added, were used to constrain a central composite design with range of 0.1-0.4 %, 0-1.0 % and 0-2.0 % ( w/w ) respectively, to improve the texture and soup-absorbing ability of packed tofu. It was showed that, addition of magnesium chloride even at its minimal amount, 0.025 % ( w/w ), could solve completely problem of non-uniform texture. The soup-absrobing ability were more greatly influenced by sodium bicarbonate than by the other two processing factors, and the more sodium bicarbonate added, the greater the soup-absorbing ability was. It was also found that curdlan brought about a significant increase in hardness of packed tofu. Addition of sodium bicarbonate or baking powder, on the other hand, decreased hardness of packed tofu. The tofu with highest and lowest soup-absorbing ability, without addition of curdlan, showed high overall preference scores in sensory evaluation.

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Zhang, Zhi. "Integrating facial expressions and skin texture in face recognition." 2008. http://proquest.umi.com/pqdweb?did=1594491201&sid=1&Fmt=2&clientId=39334&RQT=309&VName=PQD.

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Thesis (Ph.D.)--State University of New York at Buffalo, 2008.<br>Title from PDF title page (viewed on Jan. 29, 2009) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Govindaraju, Venugopal Includes bibliographical references.

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HARIKESH. "HAND POSTURE RECOGNITION USING SKIN, TEXTURE AND SALIENCY MAP." Thesis, 2016. http://dspace.dtu.ac.in:8080/jspui/handle/repository/14982.

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Hand Gesture Recognition (HGR) systems are paying more attention in the present scenario due to a wide range of application in real life. These systems are based on the processing of an incoming digital image. In this thesis, the first task is to separate the hand from rest of the image. This can be achieved in several ways and depends on whether the image includes only a hand against a background or the entire person. All the techniques proposed have some limitations. Their performance is affected by the illumination or lighting conditions and complex backgrounds of the hand images. To overcome the above mentioned limitations, a new technique is proposed for Hand Posture Recognition using Skin, Texture and Saliency map which involve classification of hand gesture. It efficiently makes the use of different color spaces, skin detection, saliency map and texture of an image. To recognize the hand gesture classes the features are extracted using the proposed methodology. These features are used for the classification purpose. Finally the application of multi-class SVM classifier is employed to recognize the hand gesture class. The experiments show that the proposed model has stable performance for a wide range of images.

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"Intraracial Discrimination: Do Hair Texture and Skin Tone Really Matter?" Master's thesis, 2015. http://hdl.handle.net/2286/R.I.29677.

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abstract: ABSTRACT Colorism is the intra-racial system of inequality based on skin color, hair texture, and facial features. In the African American culture, colorism has deeply rooted origins that continue to affect the lives of African Americans today. This study examined how colorism effects perceptions of personal characteristics, personal attributes, work ability, and hiring decisions of African American women 18 and older. Participants for this study consisted of 188 African American women who self-identified as African American/Black and who were over 18 years of age living in the United States. All participants completed a demographic sheet and three instruments: Occupational Work Ethic Inventory (OWEI; Petty, 1995), Personal Attributes Questionnaire (PAQ; Spence, Helmreich, & Stapp, 1974) and Personal Efficacy Beliefs Scale (PEBS; Riggs et al., 1994). They were randomly assigned to one of six vignettes describing a young African American/Black woman applying for a job. She was described as having one of three skin-tones (light, brown, or dark) and having kinky or straight hair. A multiple analysis of variance (MANOVA) failed to reveal differences in personal characteristics, personal attributes, and work ability due to skin tone or to hair texture. Multiple linear regression analyses revealed that hair texture predicted hiring decision, after controlling for relevant demographic variables. Participant education and vignette hair texture influenced hiring decisions, accounting for 8.2% of the variance. The woman in the vignette with straight hair was more likely to be recommended for hire and more educated participants were more likely to recommend hiring. These findings suggest that education may be an important factor in changing the influence of colorism in African American culture and that hair texture may be a factor of colorism that influences hiring of applicants.<br>Dissertation/Thesis<br>Masters Thesis Counseling 2015

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Favero, Bolson Natanael. "All Organic Polymers Based Morphing Skin with Controllable Surface Texture." Thesis, 2018. http://hdl.handle.net/10754/627873.

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Smart skins are integrating an increasing number of functionalities in order to improve the interaction between the systems they equip and their ambient environment. Here we have developed an electromechanical soft actuator with controlled surface texture due to applied thermal gradient via electrical voltage. The device was fabricated and integrated with optimized process parameters for a prepared heater element [doped PEDOT: PSS (poly-(3, 4 ethylenedioxythiophene): poly (styrene sulfonic acid))], a soft actuator (Ecoflex 00-50/ethanol) and overall packaging case [PDMS (polydimethylsiloxane)]. To study a potential application of the proposed smart skin, we analyze the fluid drag reduction in a texture controlled water flow unit. As a result, we obtained a reduction of approximately 14% in the skin drag friction coefficient during the actuation. We conclude that the proposed soft actuator device is a preferred option for a texture-controlled skin that reduces the skin drag friction coefficient.

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Liu, Yen-Chen, and 劉彥錚. "Improving the Accuracy of Texture Recognition by Multiple Features." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/88398557088232734895.

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碩士<br>國立交通大學<br>電控工程研究所<br>102<br>Recently, the use of computer vision has become more popular. One of the important uses is texture recognition. There are four major problems about the texture recognition: light, scale, angle, and noise. This thesis proposed four texture features to solve the problems: Gray Level Co-occurrence Matrix, Local Binary Pattern, Local Pattern Co-occurrence Matrix and Textons-based Approach. However, using only one of the texture features, we couldn’t solve these problems at one time. For example, using Gray Level Co-occurrence Matrix as the texture feature only solved the problem of rotational change. And the problem of light illumination still remains. The thesis proposes a new method that combines multiple features. The new method could enhance accuracy of texture recognition. Thus the experiment proved that the method could enhance accuracy of texture recognition.

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(9183377), Taeksang Lee. "Improving Reconstructive Surgery through Computational Modeling of Skin Mechanics." Thesis, 2020.

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<div>Excessive deformation and stress of skin following reconstructive surgery plays a crucial role in wound healing, often leading to complications. Yet, despite of this concern, surgeries are still planned and executed based on each surgeon's training and experience rather than quantitative engineering tools. The limitations of current treatment planning and execution stem in part from the difficulty in predicting the mechanical behavior of skin, challenges in directly measuring stress in the operating room, and inability to predict the long term adaptation of skin following reconstructive surgery. Computational modeling of soft tissue mechanics has emerged as an ideal candidate to determine stress contours over sizable skin regions in realistic situations. Virtual surgeries with computational mechanics tools will help surgeons explore different surgeries preoperatively, make prediction of stress contours, and eventually aid the surgeon in planning for optimal wound healing. While there has been significant progress on computational modeling of both reconstructive surgery and skin mechanical and mechanobiological behavior, there remain major gaps preventing computational mechanics to be widely used in the clinical setting. At the preoperative stage, better calibration of skin mechanical properties for individual patients based on minimally invasive mechanical tests is still needed. One of the key challenges in this task is that skin is not stress-free in vivo. In many applications requiring large skin flaps, skin is further grown with the tissue expansion technique. Thus, better understanding of skin growth and the resulting stress-free state is required. The other most significant challenge is dealing with the inherent variability of mechanical properties and biological response of biological systems. Skin properties and adaptation to mechanical cues changes with patient demographic, anatomical location, and from one individual to another. Thus, the precise model parameters can never be known exactly, even if some measurements are available. Therefore, rather than expecting to know the exact model describing a patient, a probabilistic approach is needed. To bridge the gaps, this dissertation aims to advance skin biomechanics and computational mechanics tools in order to make virtual surgery for clinical use a reality in the near future. In this spirit, the dissertation constitutes three parts: skin growth and its incompatibility, acquisition of patient-specific geometry and skin mechanical properties, and uncertainty analysis of virtual surgery scenarios.</div><div>Skin growth induced by tissue expansion has been widely used to gain extra skin before reconstructive surgery. Within continuum mechanics, growth can be described with the split of the deformation gradient akin to plasticity. We propose a probabilistic framework to do uncertainty analysis of growth and remodeling of skin in tissue expansion. Our approach relies on surrogate modeling through multi-fidelity Gaussian process regression. This work is being used calibrate the computational model against animal model data. Details of the animal model and the type of data obtained are also covered in the thesis. One important aspect of the growth and remodeling process is that it leads to residual stress. It is understood that this stress arises due to the nonhomogeneous growth deformation. In this dissertation we characterize the geometry of incompatibility of the growth field borrowing concepts originally developed in the study of crystal plasticity. We show that growth produces unique incompatibility fields that increase our understanding of the development of residual stress and the stress-free configuration of tissues. We pay particular attention to the case of skin growth in tissue expansion.</div><div>Patient-specific geometry and material properties are the focus on the second part of the thesis. Minimally invasive mechanical tests based on suction have been developed which can be used in vivo, but these tests offer only limited characterization of an individual's skin mechanics. Current methods have the following limitations: only isotropic behavior can be measured, the calibration problem is done with inverse finite element methods or simple analytical calculations which are inaccurate, the calibration yields a single deterministic set of parameters, and the process ignores any previous information about the mechanical properties that can be expected for a patient. To overcome these limitations, we recast the calibration problem in a Bayesian framework. To sample from the posterior distribution of the parameters for a patient given a suction test, the method relies on an inexpensive Gaussian process surrogate. For the patient-specific geometry, techniques such as magnetic resonance imaging or computer tomography scans can be used. Such approaches, however, require specialized equipment and set up and are not affordable in many scenarios. We propose to use multi-view stereo (MVS) to capture patient-specific geometry.</div><div>The last part of the dissertation focuses on uncertainty analysis of the reconstructive procedure itself. To achieve uncertainty analysis in the clinical setting we propose to create surrogate and reduced order models, especially principal component analysis and Gaussian process regression. We first show the characterization of stress profiles under uncertainty for the three most common flap designs. For these examples we deal with idealized geometries. The probabilistic surrogates enable not only tasks such as fast prediction and uncertainty quantification, but also optimization. Based on a global sensitivity analysis we show that the direction of anisotropy of skin with respect to the flap geometry is the most important parameter controlled by the surgeon, and we show hot to optimize the flap in this idealized setting. We conclude with the application of the probabilistic surrogates to perform uncertainty analysis in patient-specific geometries. In summary, this dissertation focuses on some of the fundamental challenges that needed to be addressed to make virtual surgery models ready for clinical use. We anticipate that our results will continue to shape the way computational models continue to be incorporated in reconstructive surgery plans.</div>

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Glaister, Jeffrey Luc. "Automatic segmentation of skin lesions from dermatological photographs." Thesis, 2013. http://hdl.handle.net/10012/7718.

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Melanoma is the deadliest form of skin cancer if left untreated. Incidence rates of melanoma have been increasing, especially among young adults, but survival rates are high if detected early. Unfortunately, the time and costs required for dermatologists to screen all patients for melanoma are prohibitively expensive. There is a need for an automated system to assess a patient's risk of melanoma using photographs of their skin lesions. Dermatologists could use the system to aid their diagnosis without the need for special or expensive equipment. One challenge in implementing such a system is locating the skin lesion in the digital image. Most existing skin lesion segmentation algorithms are designed for images taken using a special instrument called the dermatoscope. The presence of illumination variation in digital images such as shadows complicates the task of finding the lesion. The goal of this research is to develop a framework to automatically correct and segment the skin lesion from an input photograph. The first part of the research is to model illumination variation using a proposed multi-stage illumination modeling algorithm and then using that model to correct the original photograph. Second, a set of representative texture distributions are learned from the corrected photograph and a texture distinctiveness metric is calculated for each distribution. Finally, a texture-based segmentation algorithm classifies regions in the photograph as normal skin or lesion based on the occurrence of representative texture distributions. The resulting segmentation can be used as an input to separate feature extraction and melanoma classification algorithms. The proposed segmentation framework is tested by comparing lesion segmentation results and melanoma classification results to results using other state-of-the-art algorithms. The proposed framework has better segmentation accuracy compared to all other tested algorithms. The segmentation results produced by the tested algorithms are used to train an existing classification algorithm to identify lesions as melanoma or non-melanoma. Using the proposed framework produces the highest classification accuracy and is tied for the highest sensitivity and specificity.

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Tang, Yuan-Chia, and 湯源嘉. "the improving analysis of the texture glossiness for plastic injection products." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/09117231785655510523.

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碩士<br>國立勤益科技大學<br>工業工程與管理系<br>103<br>While the consumption patterns and the car habits have changed throughout the years, all of the major motor carriers wanted to promote sale performances by upgrading cars’ abilities, appearances, and the interiors, hoping these will attract the customers. In this paper, we studied the texture glossiness on one of car interior products, the inside handle base, by implementing Taguchi Accumulation Analysis. Via experimenting 5 factors 4 level, and with L16(45) Orthogonal Array, we concluded the optimal conditions from data analysis and calculations. The predicted optimal conditions were verified by experiment, and the texture glossiness yield conditions were improved.

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Sarmento, Ana Sofia Nascimento. "Improving skin conductivity to small ions for enhanced biosignal monitoring." Master's thesis, 2018. https://hdl.handle.net/10216/114359.

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Sarmento, Ana Sofia Nascimento. "Improving skin conductivity to small ions for enhanced biosignal monitoring." Dissertação, 2018. https://hdl.handle.net/10216/114359.

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Sarmento, Ana Sofia Nascimento. "Improving skin conductivity to small ions for enhanced biosignal monitoring." Dissertação, 2002. https://repositorio-aberto.up.pt/handle/10216/114359.

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Fan, Feng-Hsu, and 樊峰旭. "Study on improving external quantum efficiency by using surface texture and wafer bonding technology." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/01297504236118938982.

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碩士<br>中原大學<br>電子工程研究所<br>92<br>High-efficiency light-emitting diodes (LEDs) are desired for many applications such as communication, illumination, traffic, and outdoor displays. It is well known that the AlGaInP LED lattice-matched GaAs substrates have the highest luminous efficiency in the yellow-to-red spectral region. However, the absorbing GaAs substrate significantly limits the light extracting performance. The inferior thermal conductivity (GaAs versus Si) also yields the joule-heating problem, which limits the luminous efficiency at high injection currents. In this thesis, wafer coated with an Au/AuBe reflector was fused to an AlGaInP LED epilayers grown on GaAs. After the wafer bonding process, the GaAs substrate was chemically removed. The metallic interlayer can be not only as an adhesive layer, but also as the reflective mirror and ohmic contact layer. The Si substrate provides a good heat sink. The performance and reliability of wafer-bonded AlGaInP /mirror/ Si light-emitting diodes have been recognized. The fusion temperature for the wafer-bonded AlGaInP LEDs was optimized at 350�aC. To roughen the AlGaInP LED surface we applied wet etching method. In the roughened surface the dynamic of light rays became chaotic. The optical phase-space distribution became random, and allowed more lights to escape from the semiconductor. We have demonstrated that there was additional 34﹪improvement in the efficiency of GaAs LED by employing the above method. The better thermal conductivity of wafer-bonded AlGaInP LED with Si substrate compared that with GaAs substrate will make it possible a high potential in high-brightness, high-power and large-area applications of the wafer-bonded AlGaInP epilayers with mirror substrate.

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Sitahall, Stacy. "The social construction of beauty and the politics of skin color and hair texture among Black women." 2005. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=370496&T=F.

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Darden, Matthew Aguirre. "Investigation of Skin Tribology and Its Effects on Coefficient of Friction and Other Tactile Attributes Involving Polymer Applications." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8993.

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Perception and sense of touch are extremely important factors in design, but until recently, the exploration of skin tribology related to tactility has been relatively untouched. In this emergence, skin-on-polymer interactions are becoming more widely investigated due to the prevalence of polymers in everyday life, and the ability to define these interactions in terms of tactility would be hugely beneficial to the engineering and design process. Previous work has investigated polymer textiles concerning tactility, examining environmental and material properties that affect skin on fabric coefficient of friction. In this study, similar friction procedure was used to compare coefficients of friction of a fingerpad across varying polymer fabrics. Forces were applied in both longitudinal and lateral directions, and it was discovered that force directionality greatly affects coefficient of friction. Specific causes have yet to be determined, but it is suspected that material weave and microscopic surface properties play a major role in this directional behavior. To complement these studies and relate them to tactility, trained human evaluators rated the samples against four tactile attributes: abrasiveness, slipperiness, sensible texture, and fuzziness. These ballots were then analyzed with Quantitative Data Analysis and shown to be repeatable among the participants, and each of the attributes were shown to be statistically independent of coefficient of friction. It should be noted, however, that fuzziness showed the greatest correlation coefficient of R^2=0.27. Material selection plays an integral role in frictional behavior, and researchers have been studying contact theory on both microscopic and macroscopic levels to determine how surface topography affects skin-polymer tribology. To negate material effects discussed in the Greenwood-Williamson contact model, frictional tests were performed on identical polypropylene plaques with textured grooves of varying dimensions. Both geometry and directionality proved to be major frictional contributors; as groove size increased, finger friction in the longitudinal direction decreased, but friction increased laterally. In addition to testing a fingerpad, friction was measured with a silicone wand to simulate a finger with different material properties. The silicone exhibited the opposite trend as skin; as groove width decreased, frictional forces increased longitudinally and decreased laterally. While topography affects frictional behavior, counterface stiffness, and intrinsic material properties may cause the trend shift between skin and silicone.

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Cheng, Tzu-Hsuan, and 鄭紫絢. "A Study of Collagen Hydrolysates Derived from Porcine Skin on Improving Osteoarthritis in Rat Model." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/92977719870501718466.

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碩士<br>國立中興大學<br>動物科學系所<br>102<br>The waste porcine skins were utilized to extract collagen and then the collagen was hydrolyzed with enzyme and dried to prepare a freeze-dried collagen hydrolyzate (CH) powder. In this study Wistar rats were divided into five groups, did not induce osteoarthritis (OA) (C); induced OA (NC); induced OA and given Viartril®-S (V); induced OA and given 20 mg / kg CH (LCH); induced OA and given 100 mg / kg CH (HCH), for a period of nine weeks. The study aim is to improve OA by using CH derived from porcine skin. The results showed: C and LCH gain weight above the trend of other groups. Moreover, according to the experimental rat cage design, rats must hold standing posture to eat the feed, the pain caused by OA will reduce feed intake, and thus other groups gain weight slower than C and LCH. The difference of knee joint diameter of NC were significantly higher than other treatments (p<0.05), LCH individually below the trend of both groups V and HCH, but these three groups had no significant difference with C. Measuring of paw edema level of V, LCH and HCH were significantly lower than NC in 3 to 9 weeks(p<0.05). Monocyte of V, LCH and HCH were significantly lower than NC from 3 weeks(p<0.05) and no significant difference with C. Ca2+ concentration of LCH and HCH were significantly lower than NC and V in 9 weeks(p<0.05) and no significant difference with C. Lactate dehydrogenase(LDH) of V and LCH were significantly lower than NC in 5 weeks(p<0.05) and no significant difference with C. V and HCH were significantly lower than C in 7 weeks(p<0.05). Catalase activity and glutathione(GSH) of V, LCH and HCH were significantly higher than NC (p<0.05). LCH and HCH had no effect on superoxide dismustase activity significantly. Tumor necrosis factor(TNF-α) and interleukin-1β(IL-1β) of NC was significantly higher than V, LCH and HCH (p<0.05). The histological result of V, LCH and HCH which articular surface is smooth and possessed integrity, chondrocytes remain in normal state and were not shrunken and edema compared with the situation of NC. Subchondral bone of V, LCH and HCH reduced the number of osteoclasts and no difference with C. Expression of matrix metalloproteinases-13(MMP-13) in LCH and HCH below the trend of NC. Among, expression of MMP-13 in LCH was the least. X ray performed in 9 weeks, C remains intact knee cartilage and bony surfaces, but in compared with femur and tibia bone of NC were causing serious damage to the articular surface unevenly were observed. Slightly wearing of joints could observe in V, LCH and HCH, and LCH was the most minor wearing among them. The extraction CH of porcine skin can slow down the progression of OA, and hope that it can be developed into a healthy food in the future, that OA patients can effectively slow the progression of OA, low side effects, enhanced the added value of by-products when pigs slaughtered, increased revenue, and reduced pollution waste.

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Dissertations / Theses on the topic 'Improving the Skin Texture'

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