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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Morfologia e morfometria das células do endotélio corneal de ovinos (Ovis aires) em diferentes faixas etárias obtidas pela microscopia especular.

Corrêa, Luis Felipe Dutra January 2011 (has links)
Baseado na carência de documentação com respeito ao endotélio da córnea de ovinos, a pesquisa teve como objetivo documentar o endotélio corneal de ovinos em diferentes faixas etárias – jovem, adulto e velho – utilizando a microscopia especular. Logo, buscou-se investigar o efeito da idade sobre a morfologia e morfometria do endotélio da córnea de ovinos. O endotélio corneano foi avaliado com auxilio do microscópio especular de contato. No total, foram avaliados 18 ovinos (Ovis aires) neste estudo. Os animais foram distribuídos em três grupos de 6 animais cada um em função da idade. O grupo I continha animais com idade de 6 meses; o grupo II, animais com idade de 2 a 4 anos; e o grupo III continha animais de 5 a 8 anos. Para a avaliação do endotélio corneal foram levados em consideração a densidade de células endoteliais (DCE), a área celular média, o polimegatismo e o pleomorfismo. Os resultados encontrados revelaram a diminuição na DCE em córneas de ovinos normais com o avanço da idade bem como o aumento da área das células endoteliais e do pleomorfismo. O presente trabalho mostrou que os parâmtros endoteliais valiados sofrem alterações decorrentes da idade. / Based on the lack of information on the corneal endothelium of ovine, the objective of this research was to evaluate the corneal endothelium of sheep in different age groups – young, adult and old - using the specular microscope. So the aim of this study was to investigate the effect of age on morphology and morphometry corneal endothelium of sheep. The corneal endothelium was evaluated with the help of a contact specular microscope. A total of 18 sheep (Ovis aires) were evaluated in this study. The sheep mob was divided into three groups of six animals each according to age. Group I contained animals 6 months old, group II contained animals from 2 to 4 years old and group III contained animals from 5 to 8 years old. To evaluate corneal endothelium we estimated the endothelial cell density (ECD), the average cell area, polymegathism and pleomorphism. The results revealed on ECD decrease in corneas of normal sheep with advancing age, as well as a corresponding increase in endothelial cell area and pleomorphism. The present work suggests that the endothelial parameters evaluated change with advancing age.
12

Morfologia e morfometria das células do endotélio corneal de ovinos (Ovis aires) em diferentes faixas etárias obtidas pela microscopia especular.

Corrêa, Luis Felipe Dutra January 2011 (has links)
Baseado na carência de documentação com respeito ao endotélio da córnea de ovinos, a pesquisa teve como objetivo documentar o endotélio corneal de ovinos em diferentes faixas etárias – jovem, adulto e velho – utilizando a microscopia especular. Logo, buscou-se investigar o efeito da idade sobre a morfologia e morfometria do endotélio da córnea de ovinos. O endotélio corneano foi avaliado com auxilio do microscópio especular de contato. No total, foram avaliados 18 ovinos (Ovis aires) neste estudo. Os animais foram distribuídos em três grupos de 6 animais cada um em função da idade. O grupo I continha animais com idade de 6 meses; o grupo II, animais com idade de 2 a 4 anos; e o grupo III continha animais de 5 a 8 anos. Para a avaliação do endotélio corneal foram levados em consideração a densidade de células endoteliais (DCE), a área celular média, o polimegatismo e o pleomorfismo. Os resultados encontrados revelaram a diminuição na DCE em córneas de ovinos normais com o avanço da idade bem como o aumento da área das células endoteliais e do pleomorfismo. O presente trabalho mostrou que os parâmtros endoteliais valiados sofrem alterações decorrentes da idade. / Based on the lack of information on the corneal endothelium of ovine, the objective of this research was to evaluate the corneal endothelium of sheep in different age groups – young, adult and old - using the specular microscope. So the aim of this study was to investigate the effect of age on morphology and morphometry corneal endothelium of sheep. The corneal endothelium was evaluated with the help of a contact specular microscope. A total of 18 sheep (Ovis aires) were evaluated in this study. The sheep mob was divided into three groups of six animals each according to age. Group I contained animals 6 months old, group II contained animals from 2 to 4 years old and group III contained animals from 5 to 8 years old. To evaluate corneal endothelium we estimated the endothelial cell density (ECD), the average cell area, polymegathism and pleomorphism. The results revealed on ECD decrease in corneas of normal sheep with advancing age, as well as a corresponding increase in endothelial cell area and pleomorphism. The present work suggests that the endothelial parameters evaluated change with advancing age.
13

Morfologia e morfometria das células do endotélio corneal de ovinos (Ovis aires) em diferentes faixas etárias obtidas pela microscopia especular.

Corrêa, Luis Felipe Dutra January 2011 (has links)
Baseado na carência de documentação com respeito ao endotélio da córnea de ovinos, a pesquisa teve como objetivo documentar o endotélio corneal de ovinos em diferentes faixas etárias – jovem, adulto e velho – utilizando a microscopia especular. Logo, buscou-se investigar o efeito da idade sobre a morfologia e morfometria do endotélio da córnea de ovinos. O endotélio corneano foi avaliado com auxilio do microscópio especular de contato. No total, foram avaliados 18 ovinos (Ovis aires) neste estudo. Os animais foram distribuídos em três grupos de 6 animais cada um em função da idade. O grupo I continha animais com idade de 6 meses; o grupo II, animais com idade de 2 a 4 anos; e o grupo III continha animais de 5 a 8 anos. Para a avaliação do endotélio corneal foram levados em consideração a densidade de células endoteliais (DCE), a área celular média, o polimegatismo e o pleomorfismo. Os resultados encontrados revelaram a diminuição na DCE em córneas de ovinos normais com o avanço da idade bem como o aumento da área das células endoteliais e do pleomorfismo. O presente trabalho mostrou que os parâmtros endoteliais valiados sofrem alterações decorrentes da idade. / Based on the lack of information on the corneal endothelium of ovine, the objective of this research was to evaluate the corneal endothelium of sheep in different age groups – young, adult and old - using the specular microscope. So the aim of this study was to investigate the effect of age on morphology and morphometry corneal endothelium of sheep. The corneal endothelium was evaluated with the help of a contact specular microscope. A total of 18 sheep (Ovis aires) were evaluated in this study. The sheep mob was divided into three groups of six animals each according to age. Group I contained animals 6 months old, group II contained animals from 2 to 4 years old and group III contained animals from 5 to 8 years old. To evaluate corneal endothelium we estimated the endothelial cell density (ECD), the average cell area, polymegathism and pleomorphism. The results revealed on ECD decrease in corneas of normal sheep with advancing age, as well as a corresponding increase in endothelial cell area and pleomorphism. The present work suggests that the endothelial parameters evaluated change with advancing age.
14

Objective Image Quality of CRT Displays under Ambient Glare: Assessing the ISO 9241-7 Ergonomic Technical Standard

Kempic, Joy III 27 April 1998 (has links)
This thesis assessed the readability of CRT displays viewed under ambient lighting conditions and then evaluated the findings with respect to the ISO 9241-7 standard. More specifically, two phases of work were conducted in this thesis. In Phase 1, seven monitors were evaluated photometrically according to the ISO 9241-7 standard to determine whether they were Class I, II, or III in positive and negative polarity. Additionally, six filters were attached to each of the monitors and their ISO Class also was assessed. All monitor/filter combinations yielded either Class I or II in positive polarity and Class II, III or failed in negative polarity. In Phase 2, fourteen participants were asked to read Tinker passages from seven display/filter combinations (tested in Phase 1) under five lighting conditions and two screen polarities. The purpose of the Phase 2 was to determine if people perform differently for Class I, II, or III monitor/filter combinations. The dependent measures were the time to read the Tinker passage (reading time) and the ability to identify the out of context word in each passage (accuracy). An Analysis of Variance was used to determine the significant effects of reading time and accuracy. The ANOVA results indicate that specular glare interferes significantly more with reading time than does diffuse glare. Diffuse (200 lux) and Specular reading times also were correlated against two ISO metrics: screen image luminance ratio (Diffuse, 200 lux) and specular reflection luminance ratio. Reading times did not correlate with the screen image luminance ratio, but they did correlate with one of the ISO specular reflection luminance ratios. The results of this thesis indicate that the ISO standard should not equally weight the screen image and the specular reflection luminance ratios. Additionally, the results indicate that it is not necessary to have separate ISO Classes for positive and negative polarity. Furthermore, people did not read differently for Class I, II, or III monitor/filter combinations. Finally, the data of this investigation provide an initial human factors database for use in assessing the validity of ISO 9241-7. / Master of Science
15

Reconstructing specular objects with Image Based Rendering using Color Caching

Chhabra, Vikram 27 April 2001 (has links)
Various Image Based Rendering (IBR) techniques have been proposed to reconstruct scenes from its images. Voxel-based IBR algorithms reconstruct Lambertian scenes well, but fail for specular objects due to limitations of their consistency checks. We show that the conventional consistency techniques fail due to the large variation in reflected color of the surface for different viewing positions. We present a new consistency approach that can predict this variation in color and reconstruct specular objects present in the scene. We also present an evaluation of our technique by comparing it with three other consistency methods.
16

Shape Estimation under General Reflectance and Transparency

Morris, Nigel Jed Wesley 31 August 2011 (has links)
In recent years there has been significant progress in increasing the scope, accuracy and flexibility of 3D photography methods. However there are still significant open problems where complex optical properties of mirroring or transparent objects cause many assumptions of traditional algorithms to break down. In this work we present three approaches that attempt to deal with some of these challenges using a few camera views and simple illumination. First, we consider the problem of reconstructing the 3D position and surface normal of points on a time-varying refractive surface. We show that two viewpoints are sufficient to solve this problem in the general case, even if the refractive index is unknown. We introduce a novel ``stereo matching'' criterion called refractive disparity, appropriate for refractive scenes, and develop an optimization-based algorithm for individually reconstructing the position and normal of each point projecting to a pixel in the input views. Second, we present a new method for reconstructing the exterior surface of a complex transparent scene with inhomogeneous interior. We capture images from each viewpoint while moving a proximal light source to a 2D or 3D set of positions giving a 2D (or 3D) dataset per pixel, called the scatter-trace. The key is that while light transport within a transparent scene's interior can be exceedingly complex, a pixel's scatter trace has a highly-constrained geometry that reveals the direct surface reflection, and leads to a simple ``Scatter-trace stereo'' algorithm for computing the exterior surface geometry. Finally, we develop a reconstruction system for scenes with reflectance properties ranging from diffuse to specular. We capture images of the scene as it is illuminated by a planar, spatially non-uniform light source. Then we show that if the source is translated to a parallel position away from the scene, a particular scene point integrates a magnified region of light from the plane. We observe this magnification at each pixel and show how it relates to the source-relative depth of the surface. Next we show how calibration relating the camera and source planes allows for robustness to specular objects and recovery of 3D surface points.
17

La robe, du voir au voile : pour une psychopathologie du corps féminin habillé / The dress, from the seeing to the veil : for a psychopathology of the dressed female body

Beillard, Ludivine 19 January 2018 (has links)
A la question freudienne « que veut une femme ? », Lacan postule l’inexistence de « Ła femme », conduite par l’idéed’une jouissance féminine dédoublée. Formulation pour le moins énigmatique qui invite à considérer le marquage inconscient d’où éclot ce que de la femme on « diffâme ». Réel d’un « pastout » que la structure langagière de l’inconscient porte en héritage à travers ses stigmates inconscients, et que l’étude des signifiants de l’habillement dégage. C’est ainsi qu’à lire l’habillement dans le champ du symbolique s’entende la supposée frivolité épinglée à l’intérêt vestimentaire. Ce qui conduit une lecture de la fonction du vêtement décalée de ses préjugés imaginaires, mais bien plutôt inscrite dans son fondement structural. De là s’interroge le nouage des femmes aux robes, et les modalités de jouissance qui les accompagnent. A se tisser comme « phallus », une robe peut s’ancrer dans la subjectivité féminine, d’où la logique sous-jacente à la multiplicité des robes dans l’existence de certaines femmes. Objet de désir, une robe engage autant une femme qui la porte qu’un homme qui la regarde, car dans sa fonction captatrice de regards, elle s’articule à la pulsion scopique et à « l’objet a » qu’est le regard. Se questionne alors sa fonction narcissique et ce qu’une femme peut trouver dans son image : serait-ce qu’à l’appui d’une robe, l’hystérique pourrait être « Autre » pour elle-même, quand pour un homme l’obstination à maintenir les femmes du côté de l’image, viendrait comme bouchage face à l’énigme de la féminité. Cela indiquerait que pour « l’Un » et « l’Autre », être belle comme une image participerait de l’accoutrement de l’amour. / To the Freudian question « What does a woman want? » Lacan postulates the non-existence of « Ⱦhe woman », driven bythe idea of a split feminine enjoyment. This less enigmatic formulation invites one to consider the unconscious hatch mark as that of the woman « defamed ». The reality of a « pastout »that the language structure of the unconscious bears inheritance through its unconscious stigmata, and which the study of the signifiers of clothing reveals. Thus, to read clothing in the field of the symbolic shows the supposed frivolity pinned to the interest of dress. This leads to a reading of the function of the garment shifted from its imaginary prejudices, but rather inscribed in its structural foundation. Thence this questions the knotting of women to dresses, and the modes of enjoyment that accompany them. To be woven as « phallus », a dress can be anchored in feminine subjectivity, hence the logic underlying the multiplicity of dresses in the existence of certain women. Object of desire, a dress engages a woman who wears it as much as a man who looks at it, because in its function of capturing glances it articulates to the scopic impulse and to the « object a » that is the glance. Then questions her narcissistic function and what a woman can find in her image: would it be that in support of a dress, the hysteric could be « Other » for herself, when for a man the obstinacy to keep women on the side of the image, would come as a blockage faced with the enigma of femininity. This would indicate that for the « One » and the « Other », to be as pretty as a picture would participate in the accoutrements of love.
18

State vector estimation in the presence of measurement uncertainty

Ekchian, L. K. (Leon K.) January 1980 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 215-218. / by Leon K. Ekchian. / M.S.
19

CHARACTERIZATION OF SEED DEFECTS IN HIGHLY SPECULAR SMOOTH COATED SURFACES

GNANAPRAKASAM, PRADEEP 01 January 2004 (has links)
Many smooth, highly specular coatings such as automotive paints are subjected to considerable performance demands as the customer expectations for appearance of coatings are continually increasing. Therefore it is vital to develop robust methods to monitor surface quality online. An automated visual assessment of specular coated surface that would not only provide a cost effective and reliable solution to the industries but also facilitate the implementation of a real-time feedback loop. The scope of this thesis is a subset of the inspection technology that facilitates real-time close loop control of the surface quality and concentrates on one common surface defect the seed defect. This machine vision system design utilizes surface reflectance models as a rational basis. Using a single high-contrast image the height of the seed defect is computed; the result is obtained rapidly and is reasonably accurate approximation of the actual height.
20

AN INTELLIGENT SYSTEM FOR THE DEFECT INSPECTION OF SPECULAR PAINTED CERAMIC TILES

LI, JINHUA 01 January 2006 (has links)
Product visual inspection is still performed manually or semi automatically in most industries from simple ceramic tile grading to complicated automotive body panel paint defect and surface quality inspection. Moreover, specular surfaces present additional challenges to conventional vision systems due to specular reflections, which may mask the true location of objects and lead to incorrect measurements. Some sophisticated optical inspection methods have already been developed for high precision surface defect inspection in recent years. Unfortunately, most of them are highly computational. Systems built on those methods are either inapplicable or costly to achieve real-time inspection. This thesis describes an integrated low-cost intelligent system developed to automatically capture and extract regular defects of the ceramic tiles with uniformly colored specular coatings. The proposed system is implemented on a group of smart cameras using its on-board processing ability to achieve real-time inspection. The results of this study will be used to facilitate the design of a robust, low-cost, closed-loop inspection system for a class of products with smooth specular coatings. The experimental results on real test panels demonstrate the effectiveness and robustness of proposed system.

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