Bibliographies: 'Texture (evaluation)' – Grafiati (2024)

Abstract:

We describe a computer procedure which allows us to introduce experimental initial textures as starting conditions for texture simulation (instead of a theoretical random texture). We apply the procedure on two batches of copper with weak initial textures and on fine-grained and coarse-grained aluminium with moderately strong initial textures. In copper the initial texture turns out to be too weak to have any significant effect. In aluminium the initial texture has a very significant effect on the simulated textures—similar to the effect it has on the experimental textures. However, there are differences between the simulated and the experimental aluminium textures that can only be explained as a grain-size effect. Possible future applications of the procedure are discussed.

Abstract:

The study shows the need for express systems, in which it is necessary to perform the analysis of texture images in various areas of diagnosis, for example, in medical express diagnostics of dermatologic disorders. Since the reliability of decision-making in such systems depends on the quality of image segmentation, which, as a rule, have the nature of spectral-statistical textures, it is advisable to develop methods for segmentation of such images and models for their presentation. A model of spectral-statistical texture is proposed, which takes into account the random nature of changes in the field variations and quasi-harmonics. On its basis, a vector-difference method of texture segmentation has been developed, which is based on the vector transformation of images of spectral and statistical textures based on vector algebra. The stages of the vector-difference method are the following: an evaluation of the spectral texture feature; an evaluation of the statistical texture feature; vector-difference transformation of texture images; a boundary detection of the homogeneous regions. For each pixel of the image in the processing aperture, the features of the spectral and statistical texture are evaluated. Statistical texture evaluation was performed by the quadratic-amplitude transformation. At the stage of vector-difference transformation of texture images, a vector of features of each pixel of an image is constructed, the elements of which are estimates of features of a spectral and statistical texture, and the modulus of the difference of two vectors is calculated. At the stage of boundary detection of homogeneous regions, Canny method was applied. The developed vector-difference texture segmentation method was applied both to model images of spectral-statistical texture and to texture images obtained in technical and medical diagnostics systems, namely, for images of psoriasis disease and wear zones of cutting tools. To compare the segmentation results, frequency-detector and amplitude-detector methods of texture segmentation were applied to these images. The quality of segmentation of homogeneous textured regions was evaluated by the Pratt's criterion and by constructing a confusion matrix. The research results showed that the developed vector-difference texture segmentation method has increased noise tolerance at a sufficient processing speed.

Abstract:

In this paper we present T1K+, a very large, heterogeneous database of high-quality texture images acquired under variable conditions. T1K+ contains 1129 classes of textures ranging from natural subjects to food, textile samples, construction materials, etc. T1K+ allows the design of experiments especially aimed at understanding the specific issues related to texture classification and retrieval. To help the exploration of the database, all the 1129 classes are hierarchically organized in 5 thematic categories and 266 sub-categories. To complete our study, we present an evaluation of hand-crafted and learned visual descriptors in supervised texture classification tasks.

Abstract:

To improve the performance of a hydrostatic bearing, a method of constructing micro-textures on the inner surface of a bearing is proposed to increase the bearing capacity and reduce the friction coefficient. In this paper, the composite texture is innovatively proposed, and the theoretical models of hydrostatic radial bearings under four situations including non-texture, square, spherical, and composite textures are established. The effect of texture shapes and texture parameters on bearing performance is numerically studied and the influence level of various factors on bearing performance is evaluated innovatively using the cross-correlation analysis. The results show that the presence of a micro-texture can improve the bearing capacity and reduce the friction coefficient of the bearing compared with smooth surface bearings; the composite micro-texture increases the bearing capacity by about 9.5%, the stiffness increases by about 8.2%, and the friction coefficient is reduced by about 10.5%; there is an optimal micro-texture unit area ratio (between 30% and 40%) making the bearing capacity largest and the friction coefficient smallest; finally, the influence level of various factors on the bearing performance is evaluated. The relative depth of the texture has the greatest influence on it, followed by the number of textures, and finally the unit area ratio. The above results will provide a theoretical basis for the design of hydrostatic bearings with micro-textures.

Abstract:

Purpose The purpose of this study is to investigate the influence of texture on hydrodynamic lubrication performance of slide surface from the perspective of skewness and kurtosis. Design/methodology/approach Hydrodynamic lubrication theoretical model of textured surface was established based on two-dimensional Reynolds equation, and finite difference algorithm was used as the numerical approach in the paper. Skewness and kurtosis of surface were obtained by discrete calculation. Findings Numerical analysis results show that the influence law of texture types on skewness, kurtosis and hydrodynamic lubrication was the more negative skewness and higher kurtosis, the better hydrodynamic lubrication performance when texture cross section contour and geometric parameters were the same. Similarly, the same influence law of skewness, kurtosis and hydrodynamic lubrication performance by texture cross-section contour was observed. However, it was unable to evaluate the effect of texture angle on hydrodynamic lubrication performance of textured surface from the perspective of skewness and kurtosis. Originality/value This paper confirms the feasibility of evaluating influence of texture types and texture cross-section contour on hydrodynamic lubrication performance from the perspective of skewness and kurtosis and provides a way to optimize texture type and texture cross section.

Abstract:

AbstractAustenite–ferrite duplex steels generally consist of two differently textured polycrystalline phases with different glide mechanisms. For estimating the effective mechanical behavior of heterogeneous materials, there exist well established approaches, two of which are the classes of mean-field and full-field methods. In this work, the local fields resulting from these different approaches are compared using analytical calculations and full-field simulations. Duplex steels of various textures measured using X-ray diffraction are considered. Special emphasis is given to the influence of the crystallographic texture on the stress and strain distributions.

Abstract:

Two- and three-dimensional macrotexture characteristics of various surfaces were measured using five different testing methods including sand patch method, laser profiler, laser texture scanner, circular texture meter, and x-ray computed tomography (CT) scanning. A dynamic friction tester was also used to measure the friction resistance of the same surfaces. Asphalt and Portland cement concrete samples of various mix designs and finishes and other commonly manufactured textured samples were used. Relationship between the macrotexture and friction was investigated. Mean texture depth (MTD) of 26 laboratory specimens was obtained from volumetric sand patch tests. Two-dimensional profiles and mean profile depth (MPD) of specimens were measured by a laser profiler. A laser texture scanner and a circular texture meter were also used to calculate the MPD of sample surfaces. Three-dimensional rendering of the surfaces were obtained from laser texture scanner and x-ray CT scans. Using the experimental data collected in this study, relationships between friction resistance and macrotexture obtained from different methods were investigated. The estimated texture depths predicted from laser profiler, laser texture scanner, and CT meter were comparable to the MTD obtained from sand patch tests. Also, the friction resistance increased with increasing surface macrotexture.

Abstract:

As the main place of people’s daily activities, indoor space (its size, shape, colors, material and textures, and so on) has important physical, emotional and health-based implications on people’s behavior and quality of life. Material texture is an integral part of architectural environment perception and quality evaluation, but the effect of material texture on perceptual spaciousness lacks the support of experimental data. This research examined the effects between different wall textures on the observer’s perception of spaciousness in indoor space, the influence of wall texture changes in different room sizes, and how the associational meaning of texture affects the degree of influence of wall texture on the spaciousness of indoor space. By using VR technology and the magnitude estimation (ME) analysis method, the authors found that the effect of wall texture on perceptual spaciousness varies depending on the wall material, and the textural effect is affected by room size. The perception of spaciousness is influenced by the observer’s associational meaning of material texture, and the influence of associational meaning of material texture varies contingent on the room size. In relatively small rooms, the objective aspect (such as hardness, surface reflectivity, texture direction and texture depth) of the wall texture has a significant impact on perceived space. In contrast, the effects of subjective aspects (such as affinity and ecology) become more pronounced in relatively larger rooms. This research makes up for the lack of material texture research in perceptual spaciousness, and provides a new way for the designer to choose materials for the design of a spatial scale.

Abstract:

In response to the development of new materials and the application of materials and components in new technologies the direct measurement, calculation and evaluation of textures and residual stresses has gained worldwide significance in recent years. Non-destructive analysis for phase specific residual stresses and textures is only possible by means of diffraction methods. The determination of global texture and the local variation of texture for example by inhomogeneous deformation are very important due to the coherence between the texture and the physical and mechanical properties of materials.

Abstract:

Students who are blind or have low-vision (BLV) do not have the same access to graphical curricular content as their sighted peers. This significantly affects their education, particularly in STEM subjects. Introduction of interactive tactile graphics is one of the only ways for BLV students to access graphical content, and is uniquely suited to teaching drawing skills. The goal of this engineering design project was to expand the capacity of printing technology that produces interactive raised-line graphics by creating a system to print textures that meet specific criteria for usefulness. The addition of textures to tactile graphics is essential for the graphics to be unambiguous and to communicate information about spaces and regions. Maps, geometric figures and graphs are prime examples.The system developed in this project for printing tactile textures was designed as an enhancement of an existing beta prototype printer for interactive tactile graphics co-developed at UVM and E.A.S.Y. LLC. Preliminary experimentation indicated that varying the size of the drawing stylus tip would afford the greatest range of printed textures. Based on this finding, the Texture Creation System (TCS) was designed with this new functionality. This thesis describes the process by which the categories of possible designs were refined and how the TCS - based on a system of interchangeable self-locking tapered tips - was designed, built, revised, and tested.We developed a set of six tactile textures (the Texture Set) as examples of the capabilities of the TCS. We then designed and performed an experiment in which six BLV subjects assessed the textures based on their Distinctness, Recognizability, and Variability in Degree. In all tests that mimic real-world use, the Texture Set was found to be successful in at least 75% of trials. The design also successfully addressed constraints for speed of operation, system cost, noise volume, and compatibility with the beta printer. The design also met standards for reliability and mechanical strength. Future engineering will be required to add sensors to monitor mechanical operation. Also, larger-scale user testing of the Texture Set (and other textures) will be needed for statistical significance and to provide insight into what objective properties of the textures elicit certain subjective responses, i.e. why certain textures meet design criteria better than others.

Abstract:

This thesis presents a preliminary investigation into the determination of enginerring important surface texture (of around a few microns) using ultrasonic pulse-echo signals. Current texture measurements and parameterisation techniques are reviewed, identifying their deficiencies, the requirements of a texture measurement device and the potential benefits of an ultrasonic technique. Plane compressional wave, high resolution, commercial NDT probes are considered, with the received signal being modelled as a first type Fredholm equation. The characteristics of these probes are considered in detail and realistic numerical simulations are presented, showing the variation in sound field and receiver voltage with the geometry and electrical condition of the test configuration. Inversion of the signal model is considered as a direct and useful route to characterising the surface. Techniques for this inversion are reviewed indicating their salient features and showing their inter-relationships. Several linear inversion techniques are considered in detail, using numerical simulations. These demonstrate their characteristics and the predictability of their performance. A simple 'interpolation' technique is shown to yield excellent results when applied under appropriate conditions. The Maximum Entropy algorithm is shown to yield significant improvements over linear techniques, in terms of reduced noise and filter artefacts and also possibly in improved resolution. Various characteristics of the algorithm performance are considered. Finally, preliminary results using real pulse echo signals are considered, with Maximum Entropy again yielding considerably superior results. While the achievable resolution is still somewhat below that desired, these results clearly demonstrate that the use of ultrasonics for surface texture evaluation is highly feasible and that the continued investigation of these, and other, ultrasonic techniques is fully justified.

Abstract:

Master of Science
Department of Animal Sciences and Industry
Travis G. O'Quinn
The objective of this research was to evaluate the role of marbling texture on beef palatability, muscle histology, and collagen characteristics of beef strip loin steaks. Beef strip loins (n = 117) were selected from three quality grade treatments [Top Choice (Modest[superscript 00] – Moderate[superscript 100] marbling), Low Choice (Small[superscript 0] – Small[superscript 100] marbling), and Select (Slight[superscript 0] – Slight[superscript 100] marbling)] to equally represent three different marbling texture groups: fine, medium and coarse, via visual appraisal with the USDA marbling texture standards. Consumers (n = 104) rated all marbling texture groups similar (P > 0.05) for tenderness, juiciness, flavor, and overall liking, as well as rated a similar (P > 0.05) percentage of samples from each marbling texture group acceptable for each palatability trait. Moreover, consumers indicated no preference (P > 0.05) among marbling texture groups for visual desirability or likelihood to purchase. There were no differences (P > 0.05) among marbling texture treatments for Warner-Bratzler shear force, slice shear force, and pressed juice percentage. However, trained sensory panelists rated coarse marbled steaks higher (P < 0.05) than fine or medium marbled steaks for both beef flavor intensity and sustained juiciness as well as higher (P < 0.05) for initial juiciness than medium textured steaks. This minimal impact on palatability was further supported through evaluation of muscle histology and collagen traits. Marbling texture did not affect collagen characteristics, as coarse marbled steaks were similar (P > 0.05) to both fine and medium marbled steaks for soluble collagen, insoluble collagen, and total collagen content. Furthermore, all marbling texture groups (fine, medium, and coarse) performed similarly (P > 0.05) during the peak thermal transition phase of the perimysial fraction of collagen. However, marbling texture impacted (P < 0.05) adipocyte cross-sectional area, where coarse steaks had larger adipocytes in comparison to fine marbled steaks, but medium marbled steaks were similar (P > 0.05) to both coarse and fine marbled steaks. Similarly, quality grade affected adipocyte size, as Top Choice and Low Choice possessed larger (P < 0.05) adipocytes than Select steaks. However, marbling texture did not impact (P > 0.05) perimysial thickness. Additionally, marbling texture did not affect the percentage of myosin heavy chain (MHC) Type I fibers within each steak. However, medium marbled steaks possessed a greater (P < 0.05) percentage of MHC Type 2A fibers than both fine and coarse marbled steaks. The opposite trend was displayed in the percentage of MHC Type IIX fibers, as fine and coarse marbled steaks possessed more (P < 0.05) MHC Type IIX fibers in comparison to medium marbled steaks. There were no differences (P > 0.05) among quality grades for fiber type or marbling texture and quality grade for fiber cross-sectional area. Results from this study indicate marbling texture has minimal impact on eating quality and muscle histology; therefore coarse marbled carcasses should not be excluded from current and future branded beef programs.

Abstract:

Ler à primeira vista ao órgão é considerada uma tarefa complexa, visto que na execução do instrumento é necessário conciliar a leitura de três pentagramas e a utilização de pés e mãos simultaneamente. O objetivo desta pesquisa é investigar as abordagens apresentadas por organistas na tarefa de leitura à primeira vista com dois trechos contrastantes (texturas homofônica e polifônica). Estudos apontam que a diferença de textura pode influenciar o resultado na leitura à primeira vista. Outros objetivos incluem: investigar se aspectos de análise musical são utilizados conscientemente na prática da leitura à primeira vista; observar o desempenho em leitura à primeira vista com sujeitos de diferentes níveis de formação e/ou experiências musicais; identificar os aspectos observados pelos participantes referente à leitura e à autorreflexão do processo. Surgem as seguintes questões de pesquisa: o resultado da leitura à primeira vista ao órgão é mais satisfatório no trecho homofônico ou no polifônico? A autoavaliação após assistir ao vídeo modifica a percepção de sua interpretação? Dez sujeitos de idades e níveis de formação musical distintos, vinculados à Universidade Federal do Rio Grande do Sul (UFRGS) foram selecionados. Utilizou-se questionário, filmagem das execuções dos dois trechos, duas entrevistas semiestruturadas, mostra dos vídeos das execuções para os participantes e avaliadores externos. Concluímos que a autoavaliação posterior à mostra do vídeo modificou a percepção da execução com a maioria dos participantes, mostrando-se uma ferramenta útil neste processo. Os níveis de formação não foram determinantes na textura homofônica, e a textura contrapontística foi considerada a mais difícil pela maioria.
Sight-reading on the organ is a complex task since this instrument requires one to reconcile reading in three staves while playing with feet and hands simultaneously. The purpose of this research is to investigate the approaches used by organists in a sight-reading exercise with two contrasting excerpts, one of homophonic and the other of polyphonic texture. Studies indicate that the difference in texture can influence the result of sight-reading tasks. Others goals include: to determine if aspects of musical analysis are utilized consciously during sight-reading; observe the performance in sight-reading with subjects of different levels of training and/or musical experiences; identify the aspects, observed by the participants relative to sight-reading and self-reflection. Thus, the research questions arise: Is the result of sight-reading on the organ more satisfactory in homophonic or polyphonic excerpts? Did the self-evaluation after watching the video modify the perception of their interpretations? Ten subjects of distinct ages and music backgrounds were selected, all linked to the Universidade Federal do Rio Grande do Sul (UFRGS). A questionnaire, videos of the performance of both excerpts, two semi-structured interviews and the exhibit of the videos to the participants were used. The audios of the performances were submitted to seven external evaluators. We concluded that self-evaluation after watching their videos modified the perception of the majority of the participants, proving to be a useful tool in this process. The musical background was not determinant in the homophonic texture, and the contrapuntal texture was considered more difficult among most participants.

Abstract:

Les propriétés sensorielles des matériaux constituent un élément important de la valeur perçue. L’enjeu est de mettre en relation 3 espaces de caractérisation des matériaux : un espace physique décrit par des données mesurables par des instruments, un espace psychophysique décrit par des données mesurables par l’appareil perceptif humain, un espace sémantique qui traduit une perception plus globale du matériau. Des méthodes de l’analyse sensorielle sont utilisées pour collecter des données de perception visuelle, tactile et visio-tactile. En parallèle, la sensation tactile est étudiée plus en détail à l’aide d’instruments de tribologie tactile. Les différents jeux d’échantillons sélectionnés permettent d’explorer les 3 espaces de caractérisation. L’analyse des vibrations induites par le contact entre le doigt et des textures artificielles, périodiques et isotropes, montre que la valeur efficace du signal d’accélération ainsi que le coefficient de frottement sont cohérents avec les résultats des tests de perception tactile. En étudiant des archétypes du bois, il apparaît que les échantillons sont différenciés selon deux critères principaux : la rugosité et l’hétérogénéité. Ce dernier faisant référence à la présence ou non de singularités caractéristiques du bois. Par ailleurs, l’analyse des vibrations induites est cohérente avec les résultats des tests de perception tactile. Enfin, l’étude d’un même ensemble de textures présentées sous forme d’un disque de matière et sous forme d’un objet identifié a permis de montrer que, contrairement aux textures artificielles, les textures naturelles ou identifiables sont perçues de manière similaire dans les deux contextes de présentation
The sensory properties of material provide leverage of perceived value. The challenge is to relate 3 spaces of material characterization: a physical space describe by measurable data using instruments, a psychophysical space describes by measurable data collected with the human perceptive system, and a semantical space which represent a more global perception of the material. Sensory evaluation methods are used to collect data of visual, tactile and visio-tactile perception. In parallel, the tactile sensation is studied more in detail using tribo-tactile instruments. The different sets of samples allow the exploration of the 3 characterization spaces. The analysis of friction induced vibrations when the finger is scanning periodic and isotropic surfaces reveal that the root mean square value of the acceleration spectra as well as the friction coefficient are coherent with the tactile perception test results. The study of wood archetype texture shows that samples discrimination is based on two main criteria: the roughness and the heterogeneousness, the latter referring to the presence or not of characteristic peculiarities of the wood. Besides, the analysis of friction induced vibrations is also coherent with the results of the tactile perception test. Finally, the study of same set of textures presented in the form of piece of material and in the form of an identified object shows that, contrary to the artificial textures, the natural or familiar textures are perceived in a similar way in both contexts of presentation

Abstract:

De nouvelles options thérapeutiques sont en cours d'introduction pour les maladies musculaires génétiques telles que les dystrophies musculaires et les myopathies congénitales, maladies jusque là sans traitement causal. Ces développements récents ont suscité un intérêt renouvelé et croissant pour les méthodes atraumatiques en vue de caractériser et de suivre les muscles atteints, en particulier pendant et après une intervention thérapeutique. Dans ce contexte, les modèles animaux sont essentiels pour mieux comprendre les mécanismes des maladies et pour tester des nouvelles thérapies. Récemment, il y a eu des avancées significatives dans l'évaluation atraumatique de modèles murins de maladies musculaires génétiques. Néanmoins, nombre de lignées de souris n'ont pas encore été caractérisées de façon atraumatique et il reste à mettre au point des méthodes plus sensibles pour identifier précocement des altérations subtiles dans le muscle des souris malades. L'objectif de cette thèse est d'appliquer des techniques atraumatiques innovantes à l'étude du muscle de modèles murins de maladies musculaires génétiques avec des phénotypes variés. Trois lignées de souris modèles de dystrophies musculaires (mdx, Large_myd et mdx/Large_myd) et une lignée de souris modèle de la myopathie congénitale (KI-Dnm2_R465W) ont été étudiées par des méthodes de Résonance Magnétique Nucléaire (RMN). Deux lignées dystrophiques (Large_myd et mdx/Large_myd) plus des souris normales après une blessure ont été étudiées par micro-tomographie (micro-CT). En RMN, toutes les souches de souris affectées ont présenté un T2 musculaire augmenté, en relation avec une gamme d'anomalies histologiques, y comprises nécrose et inflammation, mais aussi des groupes de fibres en régénération ou des fibres avec altérations de l'architecture. Avec la combinaison de la RMN et de l'analyse de la texture, il a été possible d'identifier sans ambiguïté toutes les lignées dystrophiques, alors que la seule mesure du T2 ne permettait pas de les différencier. Les souris mdx ont présenté des altérations fonctionnelles et morphologiques du réseau vasculaire musculaire. Pour les souris KI-Dnm2_R465W, des études préliminaires ont révélé une tendance à développer des altérations fonctionnelles musculaires. Finalement, les images de micro-CT n'ont pas pu détecter des différences du contenu musculaire dans les souris dystrophiques. L'ensemble des résultats non seulement enrichit le panel de modèles murins de maladies génétiques musculaires caractérisés de manière atraumatique, il révèle également un certain degré de spécificité des anomalies dans l'imagerie, comme l'a montré l'analyse de texture. Les résultats démontrent aussi que des méthodes de RMN non-invasives peuvent être assez sensibles pour identifier des altérations subtiles dans le phénotype musculaire murin, même à des stades précoces. Cette thèse a été développée dans le cadre d'une co-tutelle internationale entre la France et le Brésil, et elle a comporté un important transfert de compétence, qui a permis de réaliser les premières explorations atraumatiques du muscle murin effectuées au Brésil
Novel therapeutic approaches are being introduced for genetic muscle diseases such as muscle dystrophies and congenital myopathies, all of them having remained without cure so far. These recent developments have motivated a renewed and augmented interest in non-invasive methods for muscle characterization and monitoring, particularly during and after therapeutic intervention. In this context, animal models are essential to better understand the disease mechanisms and to test new therapies. Recently, significant advances in the non-invasive evaluation of mouse models for genetic muscle diseases have been achieved. Nevertheless, there were still several mouse strains not characterized non-invasively, and it was necessary to develop sensitive methods to identify subtle alterations in the murine affected muscle. The purpose of this thesis was to apply non-invasive techniques in the study of murine models for genetic muscle diseases with variable phenotypes. Three mouse models for muscle dystrophy (mdx, Large_myd, mdx/Large_myd) and one mouse model for congenital myopathy (KI-Dnm2_R465W) were studied with Nuclear Magnetic Resonance (NMR) methods. Two dystrophic strains (Large_myd, mdx/Large_myd) and normal mice after injury were studied through micro-Computed Tomography (micro-CT). On NMR, all affected mouse strains presented increased muscle T2, which could be related to variable features in the histological evaluation, including necrosis and inflammation, but also to clusters of fibers under regeneration or with altered cytoarchitecture. The combination of NMR and texture analyses allowed the unambiguous differential identification of all the dystrophic strains, although it was not feasible when comparing the muscle T2 measurements only. Mdx mice showed functional and morphological alterations of vascular network. In the KI-Dnm2_R465W mice, a pilot study revealed tendencies of functional impairment. Finally, micro-CT images were unable to detect differences in muscle´s content in dystrophic mice. Altogether, these results not only increased the number of murine models for genetic muscle diseases non-invasively characterized, it also demonstrated some degree of specificity of the imaging anomalies, as revealed by texture analysis. It also showed that non-invasive NMR methods can be sensitive enough to identify subtle alterations in murine muscle phenotype, even in early stages. This thesis was developed under an international joint supervision between France and Brazil, and comprised an important transfer of technology, with the first non-invasive studies of murine muscles performed in Brazil

Abstract:

Orientador: Celso Costa Lopes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho estudou o processo de obtenção de banana nanica crocante através da secagem a altas temperaturas e curto período de tempo (HTST - High Temperature and Short Time). O processo consistiu de um pré-tratamento a 70°C durante 5 minutos, de uma etapa à alta temperatura (130°C, 1400C e 150°C) e curto tempo (9, 12 e 15 minutos) e de uma etapa à temperatura de 70°C até atividade de água em torno de 0,320. De modo a verificar a influência da etapa HTST no processo, montou-se um planejamento experimental fatorial 22 com 3 pontos centrais, cujas respostas do processo foram o grau de reidratação, o parâmetro k do modelo de Lewis (para a etapa HTST, 70°C e secagem completa) e a crocância, avaliada por medidas sensoriais e instrumentais de textura. O planejamento experimental resultou numa matriz com as condições de ensaios de 130°C-9min, 130°C-15min, 150°C-9min, 150°C-15min e três pontos centrais a 140°C-12min. Banana crocante foi obtida com as condições de 140°C-12min e 150°C-15min de etapa HTST, com atividade de água de 0,345 e 0,363, respectivamente. Os resultados mostram que o melhor grau de reidratação ocorreu para os tempos de 10 e 5 minutos e que existe uma significativa relação entre a crocância e a temperatura da fase HTST. Não foi possível encontrar um ajuste adequado ao parâmetro k do modelo de Lewis para a etapa HTST e a 70°C, porque as umidades iniciais eram diferentes e promoveram grande diferença nos valores desse parâmetro. Adicionalmente, caracterizou-se a crocância de frutas comerciais liofilizadas e determinou-se a aw. Os resultados obtidos para a banana comercial liofilizada foram comparados com os da banana desidratada obtida neste estudo. As medidas instrumentais e sensoriais mostraram que ambas foram consideradas crocantes
Abstract: We present here a study about producing crispy banana using a HTST (High Temperature Short Time) process. The process involves pretreatment of the fruit during 5 minutes at 70°C, a dry HTST stage (130, 140 and 150°C and 9, 12 and 15 minutes) and, finally, a dry stage at 70°C until the water activity (aw) is near 0,300. In order to evaluate the HTST stage in the process, we used a factorial 22 design with 3 center points. The results produced by this analysis were the rehydratation degree, the model parameter of Lewis k (considering either the complete process, the HTST stage and the dry stage at 70°C). Also, crispness was analyzed according to sensorial and instrumental measurements. This process generated a matrix containing the results of several trial runs for the following settings: 130°C-9min, 130°C-15min, 150°C-9min, 150°C-15min and 3 center points at 140°C-12min. Crispy banana was obtained only with 140°C-12min and 150°C15min, where aw = 0,345 and aw = 0,363, respectively. The results show that the best rehydration degree occurs for 10 and 5 minutes. Also, there exists a relationship between the crispness (sensorial and instrumental) and the HTST stage. However, it was not possible to find a suitable value to the Lewis Model parameter k to HTST and 70°C dry stages. This is because the initial moisture of the fruits was not the same for all tests, which produced different values for k. In addition, we evaluated the crispness of commercial freeze-dried fruits and the water activity value. Finally, we compared measurements of the commercial banana with the dried banana obtained in this work. Both were considered crispy
Mestrado
Mestre em Engenharia de Alimentos

Abstract:

Glaucoma is a significant cause of blindness in the world. Doctors use computerized images to detect these diseases. Early detection of the disease increases the chances of treatment, reducing the adverse effects. This work proposes an evaluation of texture maps combinations as input to Convolutional Neural Networks for glaucoma classification in retinal images. In our experiments, we used three textures maps, three CNN architectures, and three classifiers. We achieve a Kappa =0.708±0.054 and a Accuracy = 0.859±0.021. We conclude that using the combination of texture maps can improve the automatic detection of glaucoma compared to single-channel inputs, and could be used by state-of-the-art methods to improve their classification rates.

Abstract:

A surface texture is a common design factor that affects a customer’s sensory perception of product quality. Customers perceive a surface quality using multiple sensory modalities, for example, vision and touch, and switch them through an interaction with a product, for example, a transition from vision to touch. Between such sensory modality transitions, human beings often predict subsequent modal perceptions using a prior modality, for example, predicting the tactile quality of a product from its appearance before actually touching it. We believe that a disconfirmation between prediction using a modality and an experience using another modality affects a perceived quality. In this paper, we propose a method to evaluate the quality of a surface texture with attention to the effects of a disconfirmation between a prior visual prediction and posterior tactual experience. To identify the textural factors contributing to such an effect, we conducted a sensory evaluation experiment with combinations of visual and tactile texture samples that were synthesized using a half-mirror. We demonstrate the appropriateness of the method with analysis of the results of an experiment using fourteen plastic texture samples having different textures that are commonly used in a product design.

Abstract:

The Indiana Department of Transportation (INDOT) completed a total of 25 high friction surface treatment (HFST) projects across the state in 2018. This research study attempted to investigate the durability and performance of HFST in terms of its HFST-pavement system integrity and surface friction performance. Laboratory tests were conducted to determine the physical and mechanical properties of epoxy-bauxite mortar. Field inspections were carried out to identify site conditions and common early HFST distresses. Cyclic loading test and finite element method (FEM) analysis were performed to evaluate the bonding strength between HFST and existing pavement, in particular chip seal with different pretreatments such as vacuum sweeping, shotblasting, and scarification milling. Both surface friction and texture tests were undertaken periodically (generally once every 6 months) to evaluate the surface friction performance of HFST. Crash records over a 5-year period, i.e., 3 years before installation and 2 years after installation, were examined to determine the safety performance of HFST, crash modification factor (CMF) in particular. It was found that HFST epoxy-bauxite mortar has a coefficient of thermal expansion (CTE) significantly higher than those of hot mix asphalt (HMA) mixtures and Portland cement concrete (PCC), and good cracking resistance. The most common early HFST distresses in Indiana are reflective cracking, surface wrinkling, aggregate loss, and delamination. Vacuum sweeping is the optimal method for pretreating existing pavements, chip seal in particular. Chip seal in good condition is structurally capable of providing a sound base for HFST. On two-lane highway curves, HFST is capable of reducing the total vehicle crash by 30%, injury crash by 50%, and wet weather crash by 44%, and providing a CMF of 0.584 in Indiana. Great variability may arise in the results of friction tests on horizontal curves by the use of locked wheel skid tester (LWST) due both to the nature of vehicle dynamics and to the operation of test vehicle. Texture testing, however, is capable of providing continuous texture measurements that can be used to calculate a texture height parameter, i.e., mean profile depth (MPD), not only for evaluating friction performance but also implementing quality control (QC) and quality assurance (QA) plans for HFST.

Abstract:

Multiple oil discoveries reveal the global scale and economic importance of a distinctive reservoir type composed of possible microbial lacustrine carbonates like the Lower Cretaceous pre-salt reservoirs in deepwater offshore Brazil and Angola. Marine microbialite reservoirs are also important in the Neoproterozoic to lowest Cambrian starta of the South Oman Salt Basin as well as large Paleozoic deposits including those in the Caspian Basin of Kazakhstan (e.g., Tengiz field), and the Cedar Creek Anticline fields and Ordovician Red River “B” horizontal play of the Williston Basin in Montana and North Dakota, respectively. Evaluation of the various microbial fabrics and facies, associated petrophysical properties, diagenesis, and bounding surfaces are critical to understanding these reservoirs. Utah contains unique analogs of microbial hydrocarbon reservoirs in the modern Great Salt Lake and the lacustrine Tertiary (Eocene) Green River Formation (cores and outcrop) within the Uinta Basin of northeastern Utah. Comparable characteristics of both lake environments include shallowwater ramp margins that are susceptible to rapid widespread shoreline changes, as well as compatible water chemistry and temperature ranges that were ideal for microbial growth and formation/deposition of associated carbonate grains. Thus, microbialites in Great Salt Lake and from the Green River Formation exhibit similarities in terms of the variety of microbial textures and fabrics. In addition, Utah has numerous examples of marine microbial carbonates and associated facies that are present in subsurface analog oil field cores.