971 resultados para Concept of angle


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A model of iron carbonate (FeCO3) film growth is proposed, which is an extension of the recent mechanistic model of carbon dioxide (CO2) corrosion by Nesic, et al. In the present model, the film growth occurs by precipitation of iron carbonate once saturation is exceeded. The kinetics of precipitation is dependent on temperature and local species concentrations that are calculated by solving the coupled species transport equations. Precipitation tends to build up a layer of FeCO3 on the surface of the steel and reduce the corrosion rate. On the other hand, the corrosion process induces voids under the precipitated film, thus increasing the porosity and leading to a higher corrosion rate. Depending on the environmental parameters such as temperature, pH, CO2 partial pressure, velocity, etc., the balance of the two processes can lead to a variety of outcomes. Very protective films and low corrosion rates are predicted at high pH, temperature, CO2 partial pressure, and Fe2+ ion concentration due to formation of dense protective films as expected. The model has been successfully calibrated against limited experimental data. Parametric testing of the model has been done to gain insight into the effect of various environmental parameters on iron carbonate film formation. The trends shown in the predictions agreed well with the general understanding of the CO2 corrosion process in the presence of iron carbonate films. The present model confirms that the concept of scaling tendency is a good tool for predicting the likelihood of protective iron carbonate film formation.

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The concept of crystallographic index termed the effective index is suggested and applied to the design of ceria (CeO2)-based electrolytes to maximize oxide ionic conductivity. The suggested index considers the fluorite structure, and combines the expected oxygen vacancy level with the ionic radius mismatch between host and dopant cations. Using this approach, oxide ionic conductivity of Sm- or La-doped CeO2-based system has been optimized and tested under operating conditions of a solid oxide fuel cell. In the observation of microstructure in atomic scale, both Sm-doped CeO2 and La-doped CeO2 electrolytes had large micro-domains over 10 nm in the lattice. On the other hand, Sm or La and alkaline earth co-doped CeO2-based electrolytes with high effective index had small micro-domains around 1-3 nm in the microstructure. The large micro-domain would prevent oxide ion from passing through the lattice. Therefore, it is concluded that the improvement of ionic conductivity is reflected in changes of microstructure in atomic scale. (C) 2002 Elsevier Science B.V. All rights reserved.

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By examining Japanese fictional novels, this article will discuss how anaphoric devices (noun phrases (NPs), third person pronouns (TPPs), and zero anaphors) are selected and arranged in a given discourse. The traditional view of anaphora considers the co-referential relationship between anaphoric devices to be syntagmatic; that is, a pronoun, for example, refers back to its antecedent. It also declares the hierarchical order of information values between anaphoric devices; NPs are semantically the most informative, indicating an episode boundary, and pronouns less informative. Furthermore, zero anaphora is the most referentially transparent, showing the most accessibility of a topic. However, real text shows the contrary. NPs occur frequently while there is no apparent discourse boundary, and the same episode is continuous. This is because zero anaphors and TPPs (if they occur) break down readily due to the nature of a forthcoming sentence and the NP is reinstated, in order to continue the same topic in a given discourse. Therefore, the article opposes the traditional view of anaphora. Based on the concept of text processing, using ‘mental representations’, this article will determine certain occurrence patterns of the three anaphoric devices.

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O estudo trata da dimensão territorial do conflito israelo-palestino a partir do jornalismo em quadrinhos produzidos por Joe Sacco. Para isso, procura, preliminarmente, desenvolver uma abordagem da representação espacial nos quadrinhos através de sua linguagem visual e textual, que evidencia uma percepção espacial e expressa um conjunto de significados a partir das ações que unem os personagens ao lugar. A partir desse quadro de interpretação, o presente estudo focaliza, através da análise das obras de Joe Sacco, o conflito árabe-israelense para entender os territórios palestinos ocupados como um volume político que retrata a perda de soberania política dos palestinos em sentido amplo. Esse enfoque se volta para uma reflexão a respeito do dia a dia dos palestinos através dos quadrinhos considerando o cotidiano da ocupação e sua dimensão espacial (ou seja, um conteúdo que remete ao território, uma vez que apresenta todo um conjunto de significados que evocam um sentido territorial). Assim, a pesquisa objetiva entender os territórios palestinos ocupados, procurando evidenciar em que medida os quadrinhos de Joe Sacco disponibilizam elementos para a pesquisa em Geografia, na medida em que expressam, sugere-se, uma geograficidade. Tal enfoque, que recorre ao escopo conceitual da Geografia – e notadamente ao conceito de território e seus múltiplos –, mediatizando-os através do recurso às obras de Joe Sacco, possibilita, sugere-se, um ângulo de abordagem peculiar sobre o território em locais de conflito, na medida em que, através dele, torna-se possível observar as formas de controle e precarização territorial dos palestinos em sua formação espaço-territorial.

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This article examines the priority bilateral relations of Brazil, named "strategic partnerships", both because of their tradition and historical relevance and due to the existence of political and economic cooperation projects. An assessment of these relationships, especially under Lula's administration, is made in this work, bearing in mind the concept of "strategic partnerships" and its development in Brazilian foreign policy. There will be considered partnerships with the US; Argentina; Japan; China; India; South Africa and the European Union. In the article, the meaning of the increase in these relationships is interpreted on the grounds of its significance to the international insertion strategy of Brazil

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In the last five years, climate change has been established as a central civilizational driver of our time. As a result of this development, the most diversified social processes - as well as the fields of science which study them - have had their dynamics altered. In International Relations, this double challenge could be explained as follows: 1) in empirical terms, climate change imposes a deepening of cooperation levels on the international community, considering the global common character of the atmosphere; and 2) to International Relations as a discipline, climate change demands from the scientific community a conceptual review of the categories designed to approach the development of global climate governance. The goal of this article is to discuss in both conceptual and empirical terms the structure of global climate change governance, through an exploratory research, aiming at identifying the key elements that allow understanding its dynamics. To do so, we rely on the concept of climate powers. This discussion is grounded in the following framework: we now live in an international system under conservative hegemony that is unable to properly respond to the problems of interdependence, among which - and mainly -, the climate issue.

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Abstract This article presents the increasing demands over the Brazilian Ministry of Foreign Affairs (Itamaraty) for opening its doors to other actors. This discussion will be followed by relevant theoretical and methodological analysis. We will defend the need to overcome problems related to: 1) conceptual vagueness about what the concept of participation means; 2) lack of clarity in the baseline to which comparisons are made; 3) fragile empirical basis; 4) limitations on the use of sources; and 5) how to understand the impact exerted by systemic forces.

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This study is focused on the establishment of relationships between the injection moulding processing conditions, the applied thermomechanical environment (TME) and the tensile properties of talc-filled polypropylene,adopting a new extended concept of thermomechanical indices (TMI). In this approach, TMI are calculated from computational simulations of the moulding process that characterise the TME during processing, which are then related to the mechanical properties of the mouldings. In this study, this concept is extended to both the filling and the packing phases, with new TMI defined related to the morphology developed during these phases. A design of experiments approach based on Taguchi orthogonal arrays was adopted to vary the injection moulding parameters (injection flow rate, injection temperature, mould wall temperature and holding pressure), and thus, the TME. Results from analysis of variance for injection-moulded tensile specimens have shown that among the considered processing conditions, the flow rate is the most significant parameter for the Young’s modulus; the flow rate and melt temperature are the most significant for the strain at break; and the holding pressure and flow rate are the most significant for the stress at yield. The yield stress and Young’s modulus were found to be governed mostly by the thermostress index (TSI, related to the orientation of the skin layer), whilst the strain at break depends on both the TSI and the cooling index (CI, associated to the crystallinity degree of the core region). The proposed TMI approach provides predictive capabilities of the mechanical response of injection-moulded components, which is a valuable input during their design stage.

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Dental implant recognition in patients without available records is a time-consuming and not straightforward task. The traditional method is a complete user-dependent process, where the expert compares a 2D X-ray image of the dental implant with a generic database. Due to the high number of implants available and the similarity between them, automatic/semi-automatic frameworks to aide implant model detection are essential. In this study, a novel computer-aided framework for dental implant recognition is suggested. The proposed method relies on image processing concepts, namely: (i) a segmentation strategy for semi-automatic implant delineation; and (ii) a machine learning approach for implant model recognition. Although the segmentation technique is the main focus of the current study, preliminary details of the machine learning approach are also reported. Two different scenarios are used to validate the framework: (1) comparison of the semi-automatic contours against implant’s manual contours of 125 X-ray images; and (2) classification of 11 known implants using a large reference database of 601 implants. Regarding experiment 1, 0.97±0.01, 2.24±0.85 pixels and 11.12±6 pixels of dice metric, mean absolute distance and Hausdorff distance were obtained, respectively. In experiment 2, 91% of the implants were successfully recognized while reducing the reference database to 5% of its original size. Overall, the segmentation technique achieved accurate implant contours. Although the preliminary classification results prove the concept of the current work, more features and an extended database should be used in a future work.

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Tourism has reached world importance in the economy. The competition in tourism has intensified between destinations, whether the destinations are cities, regions or countries. In this sense, the evaluation of the tourism competitiveness of these destinations may be helpful in planning and prioritizing actions that will benefit the industry. This article discusses the concept of competitiveness by the multidimensional view of performance, efficiency and unit analysis. Using the theoretical framework lifted, this article shows the 'Study on the competitiveness of the 65 destinations inducers of regional tourism development' prepared by the Tourism Ministry, the Brazilian Support Service to Micro and Small Enterprises (Sebrae) and Getulio Vargas Foundation (FGV), its assumptions that guided this study as well its methodological aspects. Based on this methodology, it was carried out a diagnosis of these 65 destinations selected by the Brazilian Ministry of Tourism to be inducers of tourism in their respective regions. The result of competitiveness reached by these 65 inductors destinations is presented in this article, providing a map of the level of competitiveness of tourism in Brazil.

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With the creationof the moving image at the end of the 19th century a new way of representing and expressing the Religious was born. The cinema industry rapidly understood that film has a powerful way to attract new audiences and transformed the explicit religious message into an implicit theological discourse of the fictional film. Today, the concept of "cinema" needs to be rethought and expanded, as well as the notion of "tTranscendental" since the strong reality effect of the film can allow a true religious experience for the spectator.

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This paper aims to evaluate the social impacts of the Tourism Development Program (Prodetur) in the northeastern town of Porto Seguro, Bahia, Brazil. The method used is based on the difference in difference technique applied to the 1991 and 2000 Census microdata. The results suggest social advances following from poverty relief based on income - where the benefits are distributed, generally, in a relatively equal manner between the native and migrant population. There is a relative deterioration in the sanitary situation, which consists of a very serious problem in the mid- and long-term, whose costs are mostly borne by the native population. Therefore, maintaining the natural capital is the main aspect that distances Porto Seguro’s tourism supply from the concept of sustainability. The article also relies on difference in difference estimators to assess the impacts of local public policies related to the sector.

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The concept of explaining the use of an old tool like the Smith chart, using modern tools like MATLAB [1] scripts in combination with e-learning facilities, is exemplified by two MATLAB scripts. These display, step by step, the graphical procedure that must be used to solve the double-stub impedance-matching problem. These two scripts correspond to two different possible ways to analyze this matching problem, and they are important for students to learn by themselves.

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INTRODUCTION: Among psychiatric disorders schizophrenia is often said to be the condition with the most disputed definition.The Bleulerian and Schneiderian approaches have given rise to diagnostic formulations that have varied with time and place. Controversies over the concept of schizophrenia were examined within European/North American settings in the early 1970s but little has since been reported on the views of psychiatrists in developing countries. In Brazil both concepts are referred to in the literature. A scale was developed to measure adherence to Bleulerian and Schneiderian concepts among psychiatrists working in S. Paulo. METHODOLOGY: A self-reported questionnaire comprising seventeen visual analogue-scale statements related to Bleulerian and Schneiderian definitions of Shizophrenia, plus sociodemographic and training characteristics, was distributed to a non-randomised sample of 150 psychiatrists. The two sub-scales were assessed by psychometric methods for internal consistency, sub-scale structure and test-retest reliability. Items selected according to internal consistency were examined by a two-factor model exploratory factor analysis. Intraclass correlation coefficients described the stability of the scale. RESULTS: Replies were received from 117 psychiatrists (mean age 36 (SD 7.9)), 74% of whom were made and 26% female. The Schneiderian scale showed better overall internal consistency than the Bleulerian scale. Intra-class correlation coefficients for test-retest comparisons were between 0.5 and 0.7 for Schneiderian items and 0.2 and 0.7 for Bleulerian items. There was no negative association between Bleulerian and Schneiderian scale scores, suggesting that respondents may hold both concepts. Place of training was significantly associated with the respondent's opinion; disagreement with a Bleulerian standpoint predominated for those trained at the University of S. Paulo. CONCLUSIONS: The less satisfactory reliability for the Bleulerian sub-scale limits confidence in the whole scale but on the other hand this questionnaire contributes to the understanding of the controversy over Bleulerian and Schneiderian models for conceptualisation of schizophrenia, the former requiring more inference and therefore being prone to unreliability.

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Since collaborative networked organisations are usually formed by independent and heterogeneous entities, it is natural that each member holds his own set of values, and that conflicts among partners might emerge because of some misalignment of values. In contrast, it is often stated in literature that the alignment between the value systems of members involved in collaborative processes is a prerequisite for successful co-working. As a result, the issue of core value alignment in collaborative networks started to attract attention. However, methods to analyse such alignment are lacking mainly because the concept of 'alignment' in this context is still ill defined and shows a multifaceted nature. As a contribution to the area, this article introduces an approach based on causal models and graph theory for the analysis of core value alignment in collaborative networks. The potential application of the approach is then discussed in the virtual organisations' breeding environment context.