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System approach to robust acoustic echo cancellation through semi-blind source separation based on independent component analysisWada, Ted S. 28 June 2012 (has links)
We live in a dynamic world full of noises and interferences. The conventional acoustic echo cancellation (AEC) framework based on the least mean square (LMS) algorithm by itself lacks the ability to handle many secondary signals that interfere with the adaptive filtering process, e.g., local speech and background noise. In this dissertation, we build a foundation for what we refer to as the system approach to signal enhancement as we focus on the AEC problem.
We first propose the residual echo enhancement (REE) technique that utilizes the error recovery nonlinearity (ERN) to "enhances" the filter estimation error prior to the filter adaptation. The single-channel AEC problem can be viewed as a special case of semi-blind source separation (SBSS) where one of the source signals is partially known, i.e., the far-end microphone signal that generates the near-end acoustic echo. SBSS optimized via independent component analysis (ICA) leads to the system combination of the LMS algorithm with the ERN that allows for continuous and stable adaptation even during double talk. Second, we extend the system perspective to the decorrelation problem for AEC, where we show that the REE procedure can be applied effectively in a multi-channel AEC (MCAEC) setting to indirectly assist the recovery of lost AEC performance due to inter-channel correlation, known generally as the "non-uniqueness" problem. We develop a novel, computationally efficient technique of frequency-domain resampling (FDR) that effectively alleviates the non-uniqueness problem directly while introducing minimal distortion to signal quality and statistics. We also apply the system approach to the multi-delay filter (MDF) that suffers from the inter-block correlation problem. Finally, we generalize the MCAEC problem in the SBSS framework and discuss many issues related to the implementation of an SBSS system. We propose a constrained batch-online implementation of SBSS that stabilizes the convergence behavior even in the worst case scenario of a single far-end talker along with the non-uniqueness condition on the far-end mixing system.
The proposed techniques are developed from a pragmatic standpoint, motivated by real-world problems in acoustic and audio signal processing. Generalization of the orthogonality principle to the system level of an AEC problem allows us to relate AEC to source separation that seeks to maximize the independence, hence implicitly the orthogonality, not only between the error signal and the far-end signal, but rather, among all signals involved. The system approach, for which the REE paradigm is just one realization, enables the encompassing of many traditional signal enhancement techniques in analytically consistent yet practically effective manner for solving the enhancement problem in a very noisy and disruptive acoustic mixing environment.
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Model Selection and Uniqueness Analysis for Reservoir History MatchingRafiee, Mohammad Mohsen 28 March 2011 (has links) (PDF)
“History matching” (model calibration, parameter identification) is an established method for determination of representative reservoir properties such as permeability, porosity, relative permeability and fault transmissibility from a measured production history; however the uniqueness of selected model is always a challenge in a successful history matching.
Up to now, the uniqueness of history matching results in practice can be assessed only after individual and technical experience and/or by repeating history matching with different reservoir models (different sets of parameters as the starting guess).
The present study has been used the stochastical theory of Kullback & Leibler (K-L) and its further development by Akaike (AIC) for the first time to solve the uniqueness problem in reservoir engineering. In addition - based on the AIC principle and the principle of parsimony - a penalty term for OF has been empirically formulated regarding geoscientific and technical considerations. Finally a new formulation (Penalized Objective Function, POF) has been developed for model selection in reservoir history matching and has been tested successfully in a North German gas field. / „History Matching“ (Modell-Kalibrierung, Parameter Identifikation) ist eine bewährte Methode zur Bestimmung repräsentativer Reservoireigenschaften, wie Permeabilität, Porosität, relative Permeabilitätsfunktionen und Störungs-Transmissibilitäten aus einer gemessenen Produktionsgeschichte (history).
Bis heute kann die Eindeutigkeit der identifizierten Parameter in der Praxis nicht konstruktiv nachgewiesen werden. Die Resultate eines History-Match können nur nach individueller Erfahrung und/oder durch vielmalige History-Match-Versuche mit verschiedenen Reservoirmodellen (verschiedenen Parametersätzen als Startposition) auf ihre Eindeutigkeit bewertet werden.
Die vorliegende Studie hat die im Reservoir Engineering erstmals eingesetzte stochastische Theorie von Kullback & Leibler (K-L) und ihre Weiterentwicklung nach Akaike (AIC) als Basis für die Bewertung des Eindeutigkeitsproblems genutzt. Schließlich wurde das AIC-Prinzip als empirischer Strafterm aus geowissenschaftlichen und technischen Überlegungen formuliert. Der neu formulierte Strafterm (Penalized Objective Function, POF) wurde für das History Matching eines norddeutschen Erdgasfeldes erfolgreich getestet.
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Joan Hambidge se idiolek oor die grense van genres : 'n korpuslinguistiese ondersoek / Mariska NelNel, Mariska January 2014 (has links)
Idiolect refers to an individual’s unique use of language. Therefore, the author of a text can be identified by his/her use of language. This study is focused on Joan Hambidge’s recognisable idiolect across the boundaries of genres. It is expected that Hambidge will have a unique and recognisable idiolect, regardless of the genre she writes in. By making use of forensic linguistic principles, methods and applications, it has been shown that it is possible to determine an individual’s idiolect. Even though forensic principles are specifically focused on identifying an author, the methodology used in the research field can be applied to a corpus linguistic study to determine how clearly an individual’s idiolect features across the boundaries of genres.
By researching the research subject, explaining her oeuvre, creating a literary background, as well as discussing the literary approaches that Hambidge uses in her respective genres, and what she writes about, the necessary literary background was created, which contributes to the complete image of Hambidge and her influences. By creating this background, it is possible to determine which external factors have an influence on Hambidge's idiolect.
Linguistic research was done to determine the origin and background of sociolinguistics; as well as factors that can influence an individual’s idiolect. The background of forensic linguistics was provided, as well as the various corpus linguistic methods that can be used in a study such as this one.
After the background was provided, the empirical analysis was executed, in which both stylistic and stylometric analyses were performed by making use of inter- and intra-corpus linguistic research, according to which Hambidge’s idiolect was identified.
To identify Hambidge’s idiolect, the Taalkommissie corpus was used as a reference corpus to determine whether the idiosyncratic characteristics that were found in the Hambidge corpus truly are a unique feature or whether they can also be found in the Taalkommissie corpus.
The application and execution of the methods made it possible to determine to which extent, if at all, Hambidge has a unique idiolect, and how this idiolect features across the boundaries of genres. The research has determined that Joan Hambidge has a unique idiolect and that the idiolect is especially clear when research is done about her corpus in its entirety. When Hambidge’s separate genres were compared to each other, it was clear that genre influences idiolect, but also that Hambidge did not follow the prescribed genre conventions. Even though the two novels that were compared, did not match as was expected, the other, various genres did agree. Various categories were identified, from which it is clear that distinguishing characteristics can be found in Hambidge’s corpus. It can therefore be said without a doubt that Hambidge has a unique idiolect across the boundaries of genres. / MA (Afrikaans and Dutch), North-West University, Potchefstroom Campus, 2014
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Contracted Preposition-Determiner Forms in German: Semantics and PragmaticsPuig Waldmüller, Estela Sophie 18 June 2008 (has links)
En el trabajo la semántica y pragmática de formas contraídas y no-contraídas en Alemán serán discutidas. Formas contraídas son preposiciones con sufijos flexionales, obligatorias en contextos en las que el contenido descriptivo del sintagma nominal es cierto de un individual o evento (expresiones que excluyen alternativas, referentes deducibles, Situative Unika, infinitivos nominalizados, referentes no específicos). Muchos autores consideran que las formas tienen artículos definidos que fusionan con una preposición. En contrario, propongo un análisis en términos de incorporación semántica en que una preposición tiene rasgos de caso, número y género. Interpretaciones únicas provienen del número singular y del contexto. Interpretaciones no específicas provienen de la semántica y el hecho de que el argumento nominal tiene menos rango que el argumento eventivo. / The semantics and pragmatics of contracted and non-contracted forms found in German will be discussed. Contracted form are prepositions with inflectional endings, and obligatory in contexts in which the descriptive content of the noun fits only one individual or event ("alternative-excluding" expressions, inferable referents, Situative Unika, nominalized infinitives, non-specific referents). Most accounts assume that contracted forms have underlying definite articles which have amalgamated with a preposition. In contrast, I propose to analyse these forms as semantically incorporating prepositions, which are inflected for (singular) number, gender, and case, and combine with noun phrases. Uniqueness effects are derived from singular number and from contextual entailments. Non-specific readings can directly be accounted for since the semantics predicts narrow scope of the nominal argument with respect to the event argument.
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Systémy kompaktních množin v deskriptivní teorii / Collections of compact sets in descriptive set theoryVlasák, Václav January 2011 (has links)
1 Title: Collections of compact sets in descriptive set theory Author: Václav Vlasák Department: Department of Mathematical Analysis Supervisor: Doc. RNDr. Miroslav Zelený, Ph.D. Author's e-mail address: vlasakmm@volny.cz Abstract: This work consists of three articles. In Chapter 2, we dissert on the connections between complexity of a function f from a Polish space X to a Polish space Y and complexity of the set C(f) = {K ∈ K(X); f K is continuous}, where K(X) denotes the space of all compact subsets of X equipped with the Vietoris topology. We prove that if C(f) is analytic, then f is Borel; and assuming ∆1 2-Determinacy we show that f is Borel if and only if C(f) is coanalytic. Similar results for projective classes are also presented. In Chapter 3, we continue in our investigation of collection C(f) and also study its restriction on convergent sequences (C(f)). We prove that C(f) is Borel if and only if f is Borel. Similar results for projective classes are also presented. The Chapter 4 disserts on HN -sets, which form an important subclass of the class of sets of uniqueness for trigonometric series. We investigate the size of these classes which is reflected by the family of measures called polar which annihilate all the sets belonging to the given class. The main aim of this chapter is to answer in...
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Consumer engagement and value enhancement through product individualisationArmellini, Juan Pablo January 2017 (has links)
Product customisation has always been a regular practice as a form of self or group identification. Previous studies have demonstrated that when investing time and effort to customise a product, an emotional attachment to that product develops. Since the 1980s, new technologies in design, manufacturing and communications have facilitated customisation practices for mass manufacturers as well as for individual consumers. For example, computer algorithms can now automate customisation (i.e. individualise), meaning that the investment of time and effort can be significantly lower than in other customisation processes. Such novel automated practices have, however, not considered the effects on emotional attachment to products, which occurs when the consumer personally engages in the process. This research investigates individualisation as a form of customisation by looking at the relationship between an individualised product and the consumers’ attribution of value and emotional attachment to the end result. This was achieved through a mixed methods approach: following a literature review, in-depth interviews, observation and experiments were carried out. Four pilot studies were conducted, involving 42 respondents (designers, company directors, and consumers). The main study engaged a further 44 respondents, profiled as one of two types of consumers depending on their critical engagement with customisation processes, namely Active Consumers (AC) that Passive Consumers (PC). Data was collected through five Action Research cycles and incorporated key features of Design-Based Research. It was then processed, coded and analysed using thematic analysis. This study makes contributions to knowledge in the area of product customisation and individualisation, as well as in the research methods developed, applied and refined over the four pilot iterations and in the main study. Results suggest that despite limiting freedom of choice, individualisation is a valuable approach to product customisation, particularly for PCs willing to relinquish part of the decision making to an automated process, in order to obtain a customised and unique design. ACs, on the other hand, value their freedom to customise their own products and see individualisation as a limitation to the customisation experience and as a hindrance to developing emotional attachment to the product. These findings have the potential to inform entrepreneurs’ and designers’ decisions to better understand and exploit the benefits associated to individualisation processes. Offering specific consumer groups opportunities to engage with the individualisation process can trigger a strong emotional product attachment and potentially generate new business opportunities.
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A singularidade vocal na composição da atriz: notações sobre um percursoLima, Elaine Cardim de 05 November 2011 (has links)
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dissertação para impressão.pdf: 1190765 bytes, checksum: caed78b341b81739d8894144e3d5ad89 (MD5) / Esta dissertação de mestrado tem por objeto uma investigação de natureza teórico-prática
sobre a expressão vocal do intérprete com o intuito de observar a revelação de sua
singularidade vocal, determinada por qualidades sonoras não usuais, particulares e universais.
A partir do registro de uma trajetória acadêmica e profissional, como atriz e pesquisadora –
explicitando a condição de sujeito e objeto desta pesquisa –, observo a apropriação dos
princípios da arte do ator e suas potencialidades com o intuito de desenvolver e registrar um
processo pessoal de desempenho vocal. Este estudo busca apoio nos pressupostos dos
pesquisadores teatrais Stanislávski, Meyerhold, Artaud e Grotowski, apresentados aqui por
meio de uma construção ficcional na qual uma atriz encontra seus mestres e procede a uma
revisão de princípios pertinentes à da prática teatral, sustentando o propósito de elaboração e
ampliação de uma pesquisa pessoal desenvolvida ao longo de sua trajetória artística.
Estabeleço como ponto de partida a observação de dois fatores identificados como inibidores
de uma expressão vocal plena: a existência de padrões vocais impostos em várias instâncias
do fazer artístico e o discurso que divide e identifica a expressão do ator, principalmente entre
corpo e voz, racional e orgânico. Tendo por princípio que o ator é uno e existe em relação; e
que a elaboração do desempenho é resultado do trabalho do artista na solução dos problemas
de atuação enfrentados ao longo de um processo de composição cênica, verifico a
possibilidade de quebra de automatismos limitadores da expressão cênica. A aplicação prática
da pesquisa se dá por intermédio do registro do processo criativo de realização de um
experimento cênico produzido a partir do conto “O ovo e a galinha”, de Clarisse Lispector. O
trabalho foi orientado de modo a fornecer os elementos de uma reflexão sobre o exercício
vocal cênico integrado aos reflexos corpóreos-imagéticos-emocionais do ator experimentados
ao longo do processo. / This Master´s thesis aims at an investigation of a theoretical and practical nature of the vocal
expression of the actor, in order to observe the revelation of their vocal singularity,
determined by unusual, particular and universal sound-related qualities. Starting from the
record of an academic and professional career as an actor and researcher – thus making my
condition of subject and object of this research explicit – I look at the acquisition of the
principles of the actor's art and its potentialities so as to develop and register a personal
process of vocal performance. This study seeks support on the assumptions of the theatrical
researchers Stanislávski, Meyerhold, Artaud and Grotowski, here presented by means of a
fictional construction in which an actor meets their masters and carries out a review of
principles concerning the theatrical practice, which supports the purpose of preparing and
expanding a personal research that has been developed throughout their artistic career. As a
starting point, I established the observation of two factors that have been identified as
inhibitors of a full vocal expression: the existence of vocal patterns that are imposed on
multiple instances of the artistic practice, and the discourse that divides and identifies the
expression of the actor, especially between body and voice, rational and organic. Having in
principle that the actor is one and exists in relation, and that the elaboration of the
performance is the result of the artist's work for solving the acting problems that are faced
throughout a scenic composition process, I verify the possibility of breaking the automatisms
that limit scenic expression. The practical application of this research is done through the
record of the creative process of a scenic experiment based on the short story "The egg and
the chicken", by Clarice Lispector. The work was directed in such a way as to provide the
elements for a reflection on the scenic vocal exercise that is integrated with the actor´s bodilyimagetical-
emotional reflections which are experienced throughout the process.
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Estabilidade assintótica de uma classe de equações quasilineares viscoelásticas com história / Asymptotic stability for a class of quasilinear viscoelastic equations with past historyRawlilson de Oliveira Araujo 23 August 2013 (has links)
Este trabalho é dedicado ao estudo do comportamento a longo prazo de uma classe de equações viscoelásticas não lineares com memória, da forma |\'upsilon IND. t\'| POT. ho\' \'upsilon IND. tt\' - DELTA \'upsilon\' - \'DELTA upsilon IND. tt\' + \'INT. SUP. t INF. \\tau\' upsilon (t- s) \'DELTA epsilon\' (s) ds = h, \'\\tau\' > 0, definida num domínio limitado de \'R POT. N\'. Tal classe de problemas foi estudada por diversos autores desde 2001, com \'\\tau = 0. Os resultados existentes são principalmente devotados à existência de soluções globais, decaimento da energia, com ou sem dissipações adicionais, existência com dados pequenos, entre outros. Entretanto, a questão da unicidade de soluções e existência de atratores globais não foram discutidas em trabalhos anteriores. No presente trabalho, apresentamos resultados de unicidade e existência de atratores globais para essa classe de problemas num contexto mais geral, incluindo o caso em que \'\\tau\' = -\'INFINITO\'. Além disso, incluímos um problema complementar, de quarta ordem onde estudamos a existência de atratores exponenciais / This work is concerned with the long-time behaviour of a class nonlinear viscoelastic equations of the form |\'upsilon IND. t\'| POT. ho\' \'upsilon IND. tt\' - DELTA \'upsilon\' - \'DELTA upsilon IND. tt\' + \'INT. SUP. t INF. \\tau\' upsilon (t- s) \'DELTA epsilon\' (s) ds = h, \'ho\' > 0, defined in a bounded domain of \'R POT. N\'. Such class of problems was studied by several authors since 2001, with \'\\tau\' = 0. Existing results are mainly devoted to global existence, energy decay, with or without additional dampings, existence with small data, among others. However, uniqueness and existence of global attractors were not considered previously. In the present work, we establish some results on the uniqueness of solutions and existence of global attractors in a more general setting, including \'\\tau\' = - \'INFINITY\'. In addition, we have added a second problem concerned with a fourth order equation where we study the existence of exponential attractors
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Unicidade e discretiza??o para problemas de valor inicialNascimento, Marcio Lemos do 13 August 2013 (has links)
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Previous issue date: 2013-08-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This paper has two objectives: (i) conducting a literature search on the criteria
of uniqueness of solution for initial value problems of ordinary differential equations.
(ii) a modification of the method of Euler that seems to be able to converge to a
solution of the problem, if the solution is not unique / O presente trabalho tem dois objetivos: (i) a realiza??o de uma pesquisa bibliografifica sobre os crit?rios de unicidade de solu??o para problemas de valor inicial
de equa??es diferenciais ordin?rias. (ii) Introduzir uma modifica??o do m?todo de Euler que parece ser capaz de convergir a uma das solu??es do problema, caso a solu??o n?o seja ?nica
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Modelamento do ensaio de indentação instrumentada usando elementos finitos e análise dimensional - análise de unicidade, variações experimentais, atrito e geometria e deformações do indentador. / Modeling of the instrumented indetation test using finite element simulations and dimensional analysis - analysis of uniqueness, experimental variation, friction , and elastic deformation and geometry of the indenter.Sara Aida Rodríguez Pulecio 31 March 2010 (has links)
A caracterização de materiais utilizando a técnica de indentação instrumentada difundiu-se significativamente na última década, devido às melhorias dos instrumentos que permitem ensaios por esta técnica e à necessidade de se fazer ensaios em pequenos volumes de materiais, como, por exemplo, em filmes finos e materiais com superfícies modificadas por tratamentos superficiais. Neste texto, abordou-se a elaboração de um algoritmo que permita o estudo da resposta de indentação de superfícies de diferentes materiais metálicos, durante e após o contato com um indentador agudo, empregando simulações por elementos finitos e análise dimensional. Na obtenção do algoritmo analisaram-se os efeitos da formação de borda (pile-up) ou da retração (sink-in) do material indentado, o coeficiente de atrito indentador-amostra, as deformações elásticas do indentador, a geometria do indentador e a variação experimental. As relações obtidas permitiram identificar uma falta fundamental de relação única entre as propriedades mecânicas e a forma da curva de indentação para curvas com razão d r/dmax>0,9, onde d r é a profundidade residual da indentação e dmax é o deslocamento máximo do indentador durante o ensaio. Da mesma forma, concluiu-se que a relação de Sneddon tem que ser corrigida tanto pela geometria da área de contato indentador-amostra quanto pela razão entre os módulos elásticos do material e do indentador (E/Ei). Como a área de contato indentador-amostra é afetada não só pela geometria do indentador mas também pelo nível de pile-up ou sink-in nos indentadores piramidais, uma relação foi identificada entre o nível de pile-up/sink-in e o fator de correção b da equação de Sneddon para os indentadores Vickers e Berkovich. Adicionalmente, pequenas diferenças foram observadas entre as curvas P-h (onde h é a profundidade de indentação abaixo da superfície original da amostra) e as curvas P-d (onde d é o valor da aproximação mútua entre indentador e amostra durante a indentação) para um mesmo valor de módulo reduzido Er quando a razão E/Ei é grande. Assim, o módulo reduzido pode sobreestimar ou subestimar a rigidez do indentador, dependendo das propriedades do material indentado. As análises neste trabalho permitiram igualmente observar que as principais limitações na obtenção das propriedades elasto-plásticas usando a curva de indentação instrumentada vêm da falta de unicidade, seguida pela geometria do indentador, isto é, diferenças entre o cone equivalente e os piramidais Vickers e Berkovich, assim como desvios em relação à geometria ideal do indentador, o que inclui arredondamento da sua ponta. Quando não há unicidade, sabendo-se informações adicionais à curva P-d, por exemplo, o valor da área residual da indentação ou o módulo elástico, uma solução única das propriedades mecânicas pode ser obtida. Em paralelo, a variação experimental pode limitar de forma significativa a precisão no cálculo das propriedades, enquanto o atrito indentador-amostra e as deformações do indentador têm efeitos menos significativos. Em termos gerais, observa-se que as funções que compõem o algoritmo desenvolvido neste trabalho permitem: (i) predizer as curvas carga-deslocamento (curvas P-d), produto do ensaio de indentação instrumentada, para um conjunto de propriedades elasto-plásticas conhecidas; (ii) identificar quando uma mesma curva P-d pode ser obtida de mais de um conjunto de propriedades do material indentado (iii) calcular as propriedades mecânicas (dureza, módulo elástico, coeficiente de encruamento e limite de escoamento) de um material usando a curva P-d quando d r/dmax<0,8 ou faixas de propriedades de materiais quando d r/dmax>0,8 e (iv) calcular as propriedades mecânicas (dureza, módulo elástico, coeficiente de encruamento e limite de escoamento) de um material usando a curva P-d e a área residual da indentação. / The interest in material characterization using instrumented indentation techniques has significantly increased in the last decade, due to improvements in testing instruments and the need to carry out tests on small volumes of materials, such as thin films or materials with surfaces modified by other surface treatments. This work addresses the development of an algorithm to analyze the indentation response of a group of metallic materials, during and after the contact with a sharp indenter, using finite element simulations and dimensional analysis. The formulation of the algorithm considered the effects of pile-up or sink-in of the indented material around the indentation, the friction coefficient between the indenter and the sample, the elastic deformation of the indenter, and the defects of the indenter tip. An analysis considering algorithm output and experimental variation was also conducted. The results allowed identifying a fundamental lack of unique relationship between the mechanical properties and the shape of the indentation curve for indentation curves with ratio d r/dmax>0,9, where d r is the residual indentation depth and dmax is the maximum indenter displacement in the test. Similarly, results allowed concluding that Sneddons equation requires a correction by both the geometry of the contact area and the ratio between the elastic moduli of the material and the indenter (E/Ei). As the shape of contact area is affected not only by the geometry of the indenter but also by the level of pile-up or sink-in in pyramidal indenters, a relationship was observed between the level of pile-up/sink-in and the correction factor b in the Sneddons equation for Vickers and Berkovich indenters. Additionally, it was found that the deformation of the indenter is not fully incorporated into indentation data analysis by the consideration of a reduced modulus (Er). Small differences between P-h curves (where h is the indentation depth below the original surface) and P-d curves (where d is the indenter/sample mutual approach) were observed for the same Er when the ratio E/Ei is large. Thus, the reduced modulus can overestimate or underestimate the indenter stiffness, depending on the mechanical properties of the indented material. Additionally, the analysis in this work has identified that the most important limitations in mechanical properties estimation using the indentation curve arise from the lack of uniqueness, followed by deviations in indenter geometry, such as differences between equivalent cone and pyramidal Vickers or Berkovich and tip defects. When non-uniqueness is present, unique solution may be obtained with the knowledge of additional information, in conjunction with P-d data, such as the residual indentation area or the elastic modulus. Furthermore, even when a unique solution is available the experimental variation may significantly decrease the accuracy in mechanical properties estimation, whereas friction and indenter deformation have less significant effects. In general, it was observed that the proposed algorithm allows: (i) predicting the load-displacement curves P-d of instrumented indentation tests for a set of known elastic-plastic mechanical properties, (ii) identifying when the same P-d curve can be obtained from more than one set of mechanical properties of the indented material, (iii) calculating the mechanical properties (hardness, elastic modulus, yield stress and strain hardening coefficient) from P-d curves when d r/dmax<0,8 or possible ranges for each mechanical property when d r/dmax>0,8 and (iv) calculating the mechanical properties (hardness, elastic modulus, yield stress and strain hardening coefficient) from P-d curves and the knowledge of the residual indentation area.
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