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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.
31

Influência do tipo de polimento pós-clareamento na alteração de rugosidade, cor e brilho da superfície de esmalte dental humano / Different polishing procedures influence in roughness, color and gloss of bleached human dental enamel surface

Ana Carolina Pedreira de Freitas 05 November 2010 (has links)
O tratamento clareador pode resultar em alterações na rugosidade superficial do esmalte dental, as quais podem ser vistas a olho nu como alterações de cor, opacidade e perda de brilho. O objetivo deste estudo foi analisar in vitro a alteração de rugosidade, cor e brilho de superfícies de esmalte dental humano após clareamento com um produto a base de peróxido de hidrogênio (PH) 38% e após polimento com fluoreto de sódio 2% neutro (FS2%) ou pasta dentifrícia contendo partículas de nano-hidroxiapatita. Para isso, coroas de incisivos centrais humanos foram preparadas e tiveram suas faces vestibulares analisadas em microscópio de força atômica (MFA), o qual determinou os valores de rugosidade [Ra, RMS, Z range e Power Spectral Density (PSD)] iniciais. A cor e o brilho destas amostras foram determinados por um espectrofotômetro. Todas as amostras foram clareadas com PH 38% por 135 minutos. Os valores de Ra, RMS, Z range e PSD foram estabelecidos pelo MFA e a cor e o brilho determinados pelo espectrofotômetro. As amostras foram divididas em dois grupos: Flúor, que recebeu um polimento com gel de FS2%; e nHA, que recebeu um polimento com pasta dentifrícia contendo partículas de nano-hidroxiapatita. Os valores de Ra, RMS, Z range, PSD, cor e brilho pós-polimento foram determinados pelo MFA e espectrofotômetro. Após o clareamento, os valores de Ra, RMS, Z range e PSD não apresentaram alteração estatisticamente significante, os valores de L* aumentaram e C* diminuiu significativamente em todas as amostras. O brilho superficial não apresentou alteração significativa após o clareamento. O grupo Flúor não apresentou alteração de rugosidade significativa para Ra, RMS, Z range e PSD após o polimento. Os valores de L*, C* e brilho superficial também não apresentaram alterações significativas após o polimento das superfícies clareadas. No grupo nHA, os valores de Ra e RMS não apresentaram alteração significativa após o polimento das superfícies clareadas, porém os valores de Z range e PSD apresentaram alteração estatisticamente significante. Em comparação à superfície clareada, L* e C* não apresentaram alteração significante após o polimento, porém o brilho superficial foi significativamente maior. O tratamento clareador de consultório mostrou ser eficiente quanto à alteração de cor e não gerou aumento na rugosidade superficial do esmalte dental. Um polimento com pasta dentifrícia contendo partículas de nano-hidroxiapatita realizado após o clareamento é capaz de aumentar o brilho e diminuir a rugosidade superficial do esmalte dental. / Bleaching treatment may result in dental enamel surface roughness alterations, which might be seen as color alterations, opacity and gloss loss. The aim of this research was to in vitro investigate roughness, color and gloss alterations of human dental enamel surfaces after bleaching treatment with 38% hydrogen peroxide (HP) and after polishing with neutral 2% sodium fluoride or dental tooth paste containing nano-hydroxiapatite particles. Human central incisors were prepared and buccal surfaces were analyzed by an atomic force microscope (AFM), which determined roughness values [Ra, RMS, Z range and Power Spectral Density (PSD)]. Surface color and gloss were determined by a spectrophotometer. All samples were bleached with 38% HP for 135 minutes. AFM determined Ra, RMS, Z range and PSD after bleaching. Color and gloss were determined by the spectrophotometer. Samples were distributed in two different groups: Fluor, which was polished with neutral 2% sodium fluoride, and nHA, which was polished with dental tooth paste containing nano-hydroxyapatite particles. Ra, RMS, Z range, PSD, color and gloss values were determined by AFM and spectrophotometer after polishing. After bleaching, Ra, RMS, Z range and PSD didnt show any statistical difference. L* increased and C* decreased significantly in all samples after bleaching. Surface gloss didnt show significant alteration after bleaching. Fluor group didnt show surface roughness alteration considering Ra, RMS, Z range and PSD after polishing. L*, C* and gloss didnt change after bleached surfaces are polished with neutral 2% sodium fluoride. Ra and RMS of nHA group didnt change significantly after polishing, but Z range and PSD showed significant alteration. Despite L* and C* didnt change, gloss increased significantly after polishing with dental tooth paste containing nano-hydroxyapatite. In-office bleaching treatment showed to be efficient as for color enhancement and didnt cause roughness alteration in dental enamel surface. An after-bleaching polishing with dental tooth paste containing nano-hydroxyapatite particles may increase gloss and decrease surface roughness of dental enamel.
32

Effect of CAD/CAM processing on esthetic characteristics of porcelain veneers

Cortes-Contreras, Eduardo 01 January 2014 (has links)
Introduction: Dentistry has changed significantly during the last two decades. Patients are more aware and demanding of the latest technologies available in restorative dentistry. The purpose of this study was to determine any possible changes on the surface roughness, gloss and color change of CAD-CAM milled porcelain veneers following repeated milling times, before and after a glazing process. Methods: A Teflon disk-shaped mold was used as a cast to take a digital impression (BlueCam) in order to fabricate cylindrical-shaped specimens. A total of one hundred (N=100) specimens porcelain veneers using Empress CAD (I10) block, were milled using the CAD/CAM CEREC-SIRONA system. The specimens representing the 1 st , 5th , 10th , 15th , 18th and 20th milling times were evaluated to determine any statistical differences regards surface roughness, gloss and color-change. Subsequently, all milled specimens representing the 1 st , 5th , 10th , 15th , 18th and 20th received a standard surface glaze and surface properties (roughness, gloss and color) were re-measured. Results: There was a statistically significant difference in roughness (Pre-glazing) between test groups at different milling times with a determined p value of 0.027. Regard roughness (Pre and Post-glazing) a statistically significant difference was found between test groups on different milling times, which present a p value of 0.18. A statistically significant difference was found in gloss (Pre and Post glazing) between test groups on different milling times. A significantly higher score after glossing, which present a p = 0.791.There was a significant difference found between samples with the same milling time, (Pre and Post the glazing process). The ΔE range between (2.5021 to 3.0418), which is considered to be detectable only by a skilled person and is clinically acceptable. Also, after perform the SEM evaluation of the burs used after 20 milling times, it showed some lost particles leaving some void on the bur surface. Conclusions: There was a statistically significant change in the surface roughness on porcelain veneers processed by CAD/CAM using the same set of burs prior to the glazing process. There was no statistical difference in porcelain surface roughness between samples of the groups Pre-Glazing. Porcelain gloss was altered significantly between groups Pre and Post-Glazing at all milling times. Porcelain Color-shade, value, and hue were significantly altered after the glazing process. There seem to be a considerable change in the physical and optical characteristics (surface roughness, gloss and color-change) after the glazing process, and this likely has a meaningful impact on the clinical aesthetic qualities of the final restoration.
33

Topographical micro-changes in corrugated board production : effects on flexographic post-print quality

Rehberger, Marcus January 2007 (has links)
The appearance and design of a package are key properties to attract and to focus the attention of a customer. Print quality contributes to a great degree to achieve these requirements. Most critical perceived in terms of quality are print defects like mottling, gloss and stripiness, which all appear in the printing of corrugated board. Stripiness is especially critical because it is a defect directly caused by the corrugated board construction. A further cause can be generated by the production process of corrugated board. Pre-studies by Odeberg Glasenapp (2004) revealed a difference in surface micro-roughness between the regions on the peak line of the liner and the regions in the valley between two peaks of the corrugation. This knowledge was the basis for the work described in this thesis. In a first stage, laboratory trials were conducted with sets of coated and uncoated samples of various grammages. The trial was set-up in order to simulate the conditions in the corrugator as closely as possible. In the evaluations, it was found out that the settings were too high. For that reason, the coated samples were influenced to a too high degree and needed to be excluded from further evaluations. With the uncoated samples, on the other hand, a change in micro surface roughness was detectable. The roughness is decreased on the peaks and the gloss appearance was the conclusion. The analysis of the printed samples focused on shifts in colour and print density. It is unclear if both are affected only surface roughness changes and/or by the typical corrugated board effect of washboarding. A full-scale test was performed in order to confirm the results of the laboratory test. A test series was chosen with coated and uncoated outer liners. Contrary to the lab-test results, the uncoated grades showed no surface roughness changes. Instead, the coated samples were affected to a great extent. The changes in surface roughness and gloss appearance were similar to the lab-test. This confirms that the lab-test samples were exposed to heat, pressure and shear to a too high degree. The print analysis of the full-scale test did not agree with the laboratory test. Gloss lines were visually detectable, but they were difficult to measure. A reason could be that the ink is capable on forming an ink film layer on top of the surface of the paper. This would cover the micro roughness of the matt parts thereby creating an almost homogeneous glossy appearance. / QC 20101116
34

Insights into Chinese Second Language Acquisition: The Relationship between Glossing and Vocabulary Recall in Reading

DeVellis, Steven S 09 August 2023 (has links) (PDF)
Reading enhancement strategies are an important tool utilized by foreign language teachers. One of the most common types of during-reading assistance is the marginal gloss, which provides first language (L1) translations of selected foreign language (L2) terms in the margins of a text. Glossing is an inherently individual approach to reading. It is predominantly motivation-driven, and provides as much assistance to the learner as he or she is willing to use it. Studies to this point have been largely inconsistent in regards to the exact usefulness of glossing, analyzing many variables such as the size, scope, and type of gloss, as well as the language read. The present study uses glossing while reading a text to investigate whether glossing helps L2 learners learn Chinese and/or helps with their long-term memory. The text was adapted from a pedagogical website for Western learners of Chinese, and the gloss comprised six of the most meaningful terms in the text. A total of 10 students learning Chinese as a foreign language participated in the present study. These beginner learners were divided into one of two groups, where the only variable was the presence or absence of a marginal vocabulary gloss. The participants were tasked with reading a short passage in Chinese while responding to comprehension questions in English. Group A read the text without the assistance of a gloss, while Group B read while using a gloss. Participants had access to the text (and gloss, if applicable) while working on the text. One week later, participants were tasked with remembering the meanings of the selected Key Terms which appeared in the passage. They were also asked to briefly summarize the text in as much detail as they remembered. In analyzing the responses of the participants after both Part 1 and Part 2, it was found that glossing provided minimal assistance in regards to vocabulary recall in the future, but did much more to aid in comprehension at the time of reading. In addition, L1 translations which appear in the gloss are more likely to be remembered than the L2 terms to which they correspond. Moreover, this study sheds light on various language acquisition theories, such as incidental vocabulary learning, involvement load, cognitive load, and Input Hypothesis. The results support the efficacy of glossing on during-reading comprehension through the aforementioned theories. Evidence of many of these theories of language processing are evident in the responses of each of the participants and will be analyzed on a case-by-case basis.
35

Тенденции развития фэшн-журналистики на примере российских и зарубежных интернет-изданий : магистерская диссертация / Trends in the development of fashion journalism on the example of Russian and foreign online publications

Власова, А. Р., Vlasova, A. R. January 2022 (has links)
Объект ВКР – отечественная и зарубежная фэшн-журналистика. Цель работы – выявление закономерностей и различий развития модной журналистики в России и за рубежом. Методы исследования: типологический анализ интернет-изданий «Vogue», «Elle», «Cosmopolitan»; контент-анализ, сравнительно-сопоставительный анализ. Результатом работы стали практические рекомендации для дальнейшего изучения фэшн-журналистики в российских и зарубежных СМИ. Научная новизна работы заключается в уточнении тенденций фэшн-журналистики на текущий год, рассмотрении аспектов влияния социальной повестки на редакционную политику глянца, а также отражения политических событий в публикациях. Издания «Vogue», «Elle», «Cosmopolitan» ранее не рассматривались исследователями в качестве эмпирического материала для сравнения контент-анализа между отечественным и зарубежными (в нашем случае — французским и американским) изданиями. Область применения полученных результатов – фэшн-журналистика, научные труды, медиакоммуникации. Значимость работы заключается в необходимости отслеживания развития модной журналистики, как одного из обширных направлений развлекательной журналистики, и, тем самым, понимании тенденций в современном обществе. / The object of the WRC is domestic and foreign fashion journalism. The purpose of the work is to identify patterns and differences in the development of fashion journalism in Russia and abroad. Research methods: typological analysis of the Internet publications "Vogue", "Elle", "Cosmopolitan"; content analysis, comparative analysis. The work resulted in practical recommendations for further study of fashion journalism in Russian and foreign media. The scientific novelty of the work lies in clarifying the trends in fashion journalism for the current year, considering aspects of the influence of the social agenda on the editorial policy of the gloss, as well as reflecting political events in publications. The publications Vogue, Elle, Cosmopolitan have not previously been considered by researchers as empirical material for comparing content analysis between domestic and foreign (in our case, French and American) publications. The scope of the obtained results is fashion journalism, scientific works, media communications. The significance of the work lies in the need to track the development of fashion journalism, as one of the broad areas of entertainment journalism, and, thereby, understanding the trends in modern society.
36

La confrontation au système de la langue française des emprunts lexicaux à l'arabe dans le domaine de la finance islamique : étude graphique, morphosyntaxique, morpholexicale, sémantique et syntaxique / .

Awwad, Mousa 15 December 2017 (has links)
Cette étude traite du sujet des emprunts lexicaux dans le domaine de la finance islamique. Etant donné que ces emprunts sont employés dans un environnement nouveau totalement différent de celui dont ils sont issus, ils rencontrent une confrontation au système de la langue receveuse. C’est cette confrontation qui se manifeste à tous les niveaux linguistiques : graphique, morphologique, morphosyntaxique, morpholexical, sémantique, contextuel et syntaxique que nous nous proposons d’étudier dans notre recherche. Au niveau graphique, nous discutons et analysons la variance formelle que les emprunts de ce domaine ont reçue en français. Au niveau morphologique, nous abordons le sujet des sigles et leur formation dans le domaine de la finance islamique. Concernant la morphosyntaxe, nous nous intéressons à la problématique de la singularisation ou la pluralisation d’un emprunt et le choix du genre de cet emprunt. Au niveau morpholexical, c’est le problème de la dérivation de ces unités qui est analysé et observé dans le corpus. Au niveau contextuel, nous reprenons la question du transcodage et du double transcodage des emprunts que nous essayons de développer, en ajoutant à la littérature déjà existante un axe qui n’a pas été traité auparavant : la problématique de transcodage des emprunts composés. La syntaxe des emprunts, sera traitée dans cette étude à partir de deux points primordiaux. Le premier étant la combinaison lexicale des emprunts avec les lexies de la langue receveuse ; le deuxième concerne, quant à lui, le comportement sémantico-syntaxique des emprunts. / This study deals with the subject of lexical loan words in the Islamic finance field. Therefore, and because these words are used in a new and totally different environment, they encounter a confrontation with the recipient language system. Hence, the purpose of the present thesis is to study this confrontation at all linguistic levels; be it graphic, morphological, morpholexical, semantic, contextual and syntactic. On the graphic level, the analysis will focus on the formal variance that loan words of this domain received in French. On the morphological level, we address the subject of acronyms and their formation in the Islamic finance field. With regard to the morphosyntax, our interest lies not only on the singularization or the pluralization of the loan words but on the choice of the grammatical gender of these loan words as well. On the morpholexical level, an analysis of the problem resulting from the derivation of these units as observed in the corpus. On the contextual level, we address again the issue of transcoding and double-transcoding of loan words that we are trying to develop. A concept that will add to the existing literature an axis that has not been dealt with before: the case of transcoding compound loan words. To sum up, this study deals with the syntax of loan words from two points of view. Firstly, it focusses on the lexical combination of loan words with the lexis of the recipient language and secondly, it focusses on the semantic-syntactic behavior these loan words.
37

A percepção de valor de uma biblioteca médica digital para o embasamento das condutos assistenciais adotadas em um hospital privado no Rio de Janeiro

Vasconcellos, Giselle Francisco de 07 January 2015 (has links)
Submitted by Giselle Francisco de Vasconcellos (gfvasconcellos@hotmail.com) on 2015-03-27T14:05:56Z No. of bitstreams: 1 Dissertação_Giselle Vasconcellos.pdf: 818582 bytes, checksum: 515159ca176c2a4cc30f6d61b8b67ad4 (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2015-04-09T16:46:18Z (GMT) No. of bitstreams: 1 Dissertação_Giselle Vasconcellos.pdf: 818582 bytes, checksum: 515159ca176c2a4cc30f6d61b8b67ad4 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-04-14T17:52:48Z (GMT) No. of bitstreams: 1 Dissertação_Giselle Vasconcellos.pdf: 818582 bytes, checksum: 515159ca176c2a4cc30f6d61b8b67ad4 (MD5) / Made available in DSpace on 2015-04-14T17:52:59Z (GMT). No. of bitstreams: 1 Dissertação_Giselle Vasconcellos.pdf: 818582 bytes, checksum: 515159ca176c2a4cc30f6d61b8b67ad4 (MD5) Previous issue date: 2015-01-07 / This study was developed in a private hospital, in Rio de Janeiro, in order to demonstrate the value of a digital medical library, as a scientific support tool for health care practices adopted by physicians, that resulted in technical glosses and loss of revenue for the institution. Through integrative review methodology, clinical literature related to technical glosses, occurred in the period from january to september 2014, were collected and analyzed from the perspective of the conceptual model presented by Cochrane (LEFEBVRE et al., 2011), which identifies the level of scientific evidence and establishes the degree of recommendation for clinical practice. During the content analysis, considering the techniques proposed by Bardin (1977), the scientific evidences, that gives value to the health care practices, were identified, as proposed by the conceptual model. In addition, the cost of the glosses were included in the analysis of the results, reinforcing the trend of the study to validate the conceptual model that recommends evidence-based medical practice to generate more effective results and better cost / benefit in health. Based on the findings, the theoretical and practical implications are discussed, as well as suggestions for future studies on the subject. / Este estudo foi desenvolvido em um hospital privado, no Rio de Janeiro, com o intuito de demonstrar o valor de uma biblioteca médica digital, como ferramenta de suporte para fundamentação científica das condutas assistenciais adotadas pela equipe médica, que resultaram em glosas técnicas e perda de faturamento para a instituição. Para isso, por meio do método revisão integrativa, foi coletada a literatura clínica referente às glosas, ocorridas durante o período de janeiro a setembro de 2014, e analisada sob a perspectiva do modelo conceitual apresentado pela Cochrane (LEFEBVRE et al., 2011) que identifica o nível da evidência científica e estabelece o seu grau de recomendação para a prática clínica. Durante a análise de conteúdo, considerando as técnicas propostas por Bardin (1977), foram identificadas as evidências científicas que conferem valor à prática assistencial, conforme proposto pelo modelo conceitual. Além disso, o valor dos itens glosados foi incluído na análise dos resultados, reforçando a tendência do estudo para a validação do modelo conceitual que recomenda a prática clínica baseada em evidências científicas para geração de resultados mais efetivos e de melhor custo/benefício na saúde. Com base nos achados, são discutidas as implicações teóricas e práticas, assim como sugestões para futuros estudos sobre o tema.
38

Česká lexikografie 15.století / Czech Lexicography of the 15th Century

Voleková, Kateřina January 2014 (has links)
Mgr. Kateřina Voleková Česká lexikografie 15. století Czech Lexicography of the 15th Century Abstract The thesis deals with Czech medieval lexicography. Based on research into rich manuscript material totalling over 350 items, it describes the development of Czech lexicography from Czech glosses in foreign-language texts and first Latin-Czech glossaries to the flourishing Czech lexicography of the 15th century covering both Latin-Czech, Czech-Latin and multilingual lexicographical works and also infrequently attested Czech monolingual dictionaries. The high number of lexicographical works is divided according to formal and content criteria. With respect to form and macrostructure we discern Czech glosses in Latin and Latin-German glossaries, a bilingual glossaries with Czech as one of the languages, alphabetaries and nomenclators and glossaries lacking an ordering criterion. With respect to the content we distinguish large dictionaries covering as many lexical items as possible on one hand and short glossaries covering only a narrowly delimited part of vocabulary on the other hand. The lexicographical works are supplied with a short description which is in case of short and yet unedited works complemented by an edition using transcription. The thesis also contains description of selected phenomena of...
39

Le Šarḥ al-Kāfiyaẗ de Ibn al-Ḥāǧib : édition critique d’un manuscrit grammatical arabe du VII e/XIII e siècle

Sartori, Manuel 10 November 2012 (has links)
Édition critique d'un traité grammatical arabe du viie/xiiie siècle, dit Imlāʾ ʿalā al-Kāfiyaẗ(«la Scolie du Précis») ou Šarḥ al-Kāfiyaẗ («Le Commentaire du Précis»), ce travail présente l'autocommentaire (1-601) fait par Ibn al-Ḥāğib (désormais IḤ, m. 646/1249) de son propre épitomé grammatical, al-Kāfiyaẗ fī al-naḥw («le Précis en syntaxe»), lui-même résumé du Mufaṣṣal («Capitulaire») de Zamaḫšarī (m. 538/1144). Cette édition se fonde sur quatre sources : trois manuscrits médiévaux (Damas ixe/xve, Dublin xe/xive et Londres 717/1317) et une édition imprimée ancienne (Istanbul, 1311/1894). Un ensemble de notes d'apparat critique justifient le choix de l'éditeur scientifique. Le texte est par ailleurs complété par une table détaillé des matières/notions, des index (versets coraniques, vers poétiques et auteurs cités) et une bibliographie. L'édition est introduite par une partie française qui rapelle l'histoire de l'édition occidentale de textes grammaticaux arabes dans laquelle elle s'insère (Introduction, I, ii-viii) et présente les détails techniques de l'édition en question (Int., II, ix-xvi). Ce travail s'attarde ensuite sur la vie de IḤ et présente ses maîtres, disciples et entourage afin de mieux connaître ce grammairien et jurologue arabe médiéval (Présentation, I, 2-28). / This work, as a critical edition of an Arabic grammatical treatise from the seventh/thirteenth century, called al-Imlāʾ ʿalā al-Kāfiyaẗ(«The Scolia of the Precis») or Šarḥ al-Kāfiyaẗ(«The Commentary on the Precis»), presents the self-commentary (p. 1-601) made by Ibnn al-Ḥāğib (now IḤ, d. 646/1249) of its own grammatical epitome, al-Kāfiyaẗfī al-naḥw («The Precis of the Syntax»), itself being the Mufaṣṣal's summary of Zamaḫšaī's (d. 538/1144). This edition is based on four sources: three medieval manuscripts (Damascus ninth/fifteenth, Dublin tenth/fourteenth and London 717/1317) and an ancient printed edition (Istanbul, 1311/1894). A set of notes that are critical apparatus justify the choice of the editor. The text is also supplemented with a detailes table of contents/concepts, index (Qur'anic verses, poetic verses and quoted authors) and an bibliography. The edition is introduced by a French section that reminds the history of Western editing of Arabic grammatical texts in which this work takes place (Introductio, I, ii-viii) and presents the technical details of the edition in question (Int., II, ix-xvi). Then this work focuses on IḤ's life and presents his masters, followres and acquaintance to learn more about this medieval Arab grammarian and law specialist (Presentation, I, 28-28). Follows a presentation of the works of IḤ, both in grammar and law fields and, in detail, the basic texte (matn) of the self-commentary, al-Kāfiyaẗ(Pres., II, 29-40).
40

Surface Characterization using Radiometric and Fourier Optical Methods

Hansson, Peter January 2003 (has links)
This thesis treats static and dynamic surface characterization using radiometric and Fourier optical methods. A Fourier optical method has been developed for real time image processing in paper production and printing applications. It has been shown that the method can be used to measure crepe frequency, an important parameter in tissue paper production, as well as to monitor the wire mark pattern at paper web velocities of up to 20 m/s. The wire mark pattern has been used to measure dimensional variations across a paper web. These are important for the mechanical properties of paper. Imaging of the moving surfaces onto a spatial light modulator, necessary for Fourier optical analysis of opaque objects, constitutes a motion blur problem. This problem has been solved by means of optical motion compensation using a rotating mirror. A rotating mirror system has also been developed for the inspection of small particles fixed to a rotating sample disc. The optical motion compensation configurations have made exposure times of more than two orders of magnitude longer than the exposure time without compensation possible. A light scattering model for opaque objects, for example coated paper, has also been developed and verified, with a coefficient of determination between theory and measurement ranging from r2=0.84 to r2=0.98, on various paper samples. The light scattering model has been used in the development of an instrument based on the photometric stereo principle. In this instrument the reflectance (or color) and topography of opaque samples are determined from two or more images of the sample illuminated from different directions. The method has been successfully used for studies of the relation between topography and print results in gravure and flexographic printing. Comparisons of surface height profiles measured with the photometric stereo method and profiles obtained with mechanical and optical scanning stylus instruments have shown coefficients of determination of up to r2=0.97. The main advantages of the method are the high speed, the scalability and the ability to obtain reflectance and surface height maps of a surface simultaneously.

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