978 resultados para Processing technique
Resumo:
A responsabilidade social é considerada fundamental para a conquista de vantagens competitivas organizacionais. A integração dos seus princípios na estratégia da organização, apresenta-se como uma linha orientadora do foco na satisfação de necessidades das partes interessadas internas e externas. As actuais limitações orçamentais têm afectado significativamente as Instituições de Ensino Superior, nomeadamente as localizadas no interior de Portugal continental, o que dificulta ainda mais a crescente diminuição de estudantes sendo necessário a implementação de estratégias de captação de estudantes nos vários ciclos, fases de idade e locais de proveniência. O sistema de gestão da responsabilidade social, referenciado na NP 4469.1:2008, apresenta um grande desafio ao modelo de gestão das organizações que o implementam, já que este sistema de gestão tem o potencial de optimizar os interesses das diversas partes interessadas. O foco da instituição passa a ser os das suas partes interessadas, maximizando os seus impactes positivos e minimizando os seus impactes negativos em resultado das suas actividades e decisões. O aumento da eficácia organizacional e a equidade dos interesses das partes interessadas, podem clarificar as funções estratégicas das Instituições de Ensino Superior. Os programas e práticas de responsabilidade social implementados nas Instituições de Ensino Superior do interior de Portugal continental são assim estrategicamente vistos, como um factor de diferenciação positiva face às suas congéneres e em consequência, assumido como um factor para a sua sustentabilidade. A presente investigação procura identificar um modelo de governação socialmente responsável que se comprometa com a dinamização de uma estratégia que preveja práticas de responsabilidade social condutoras a aumentos na confiança e reputação organizacionais nos estudantes e colaboradores das Instituições de Ensino Superior. Tendo por base a abordagem de investigação qualitativa, realizaram-se estudos de caso em duas Instituições de Ensino Superior localizadas no Alentejo, recorrendo-se a várias fontes de informação: entrevistas a 45 entrevistados, entre elementos da governação, colaboradores e estudantes, análise documental e observação participante. Como técnica de tratamento dos dados utilizou-se a análise de conteúdo através do software Atlas Ti. Os resultados da investigação empírica permitem identificar que, as duas Instituições de Ensino Superior melhoraram em termos de visibilidade externa e interna, havendo entrevistados que referem uma melhoria na confiança e reputação em resultado da adesão a práticas de responsabilidade social. O líder de uma das Instituições de Ensino Superior é reconhecido pelos seus pares como de elevado compromisso para com os princípios da responsabilidade social enquanto que o outro líder não é reconhecido da mesma forma. Os estudantes entrevistados, não reconhecem vantagens em resultado das práticas de responsabilidade social tanto ao nível da confiança como reputação organizacional; ABSTRACT: Social responsibility is considered essential to the achievement of organizational competitive advantage. The integration of its principles in the organization's strategy, presents itself as a guiding line focus on meeting the needs of internal and external stakeholders. The current budgetary constraints have significantly affected the higher education institutions, further hindering the increasing decline of students being required to implement student recruitment strategies in the various cycles of age stages and places of origin. The management system of social responsibility, referenced in NP 4469.1:2008, presents a major challenge to the model of management of organizations implementing it, since this management system, has the potential to optimize the interests of the various stakeholders. The focus of the institution happens to be out of their stakeholders, maximizing its positive impacts and minimizing the negative impacts as a result of its activities and decisions. Increased organizational effectiveness and equity interests of stakeholders can clarify the strategic functions of the higher education institutions. Social responsibility programs and Social responsibility practices implemented in higher education institutions in the interior of mainland Portugal are so strategically seen as a positive differentiating factor compared to their counterparts and therefore assumed to be a factor in their sustainability. This research seeks to identify socially responsible governance model that is committed to the promotion of a strategy which envisages conducting social responsibility practices to increases in organizational trust and reputation among students and employees of higher education institutions. Based on the qualitative research approach, there were case studies in two higher education institutions located in the Alentejo, making use of several sources of information: interviews with 45 respondents, between elements of governance, employees and students, document analysis and participant observation. As data processing technique was used content analysis by instrumental Atlas Ti. The results of empirical research identifying that the two higher education institutions have improved in terms of internal and external visibility, with respondents who report an improvement in confidence and reputation as a result of adherence to Social responsibility practices. The leader of one of the higher education institutions are recognized by their peers as high commitment to the principles of social responsibility while the other leader is not recognized in the same way. Students do not recognize advantages as a result of social responsibility practices both in terms of trust and organizational reputation.
Resumo:
This project aims to develop energy-saving methods for manufacturing tiles by using geopolymerization as an innovative processing technique. In fact, classical ceramic tiles are usually produced by sintering at temperatures ranging between 1100-1250 °C depending on natural raw materials selected for the mixture. Geopolymers, instead, are amorphous aluminosilicate inorganic polymers obtained by mixing alkali-silicate solutions with reactive aluminosilicate precursors, and geopolymerization may occur at room temperature or at temperature lower than 150 °C, and several types of waste may be used as geopolymer precursors. The possibility to obtain geopolymer tiles with properties comparable with those of ceramic tiles is extremely challenging, but geopolymerization would represent a huge energy-saving in the consolidation process as well as in natural raw materials exploitation.
Resumo:
In the present work, microstructure improvement using FSP (Friction Stir Processing) is studied. In the first part of the work, the microstructure improvement of as-cast A356 is demonstrated. Some tensile tests were applied to check the increase in ductility. However, the expected results couldn’t be achieved. In the second part, the microstructure improvement of a fusion weld in 1050 aluminium alloy is presented. Hardness tests were carried out to prove the mechanical propertyimprovements. In the third and last part, the microstructure improvement of 1050 aluminium alloy is achieved. A discussion of the mechanical property improvements induced by FSP is made. The influence of tool traverse speed on microstructure and mechanical properties is also discussed. Hardness tests and recrystallization theory enabled us to find out such influence
Resumo:
The Shadow Moiré fringe patterns are level lines of equal depth generated by interference between a master grid and its shadow projected on the surface. In simplistic approach, the minimum error is about the order of the master grid pitch, that is, always larger than 0,1 mm, resulting in an experimental technique of low precision. The use of a phase shift increases the accuracy of the Shadow Moiré technique. The current work uses the phase shifting method to determine the surfaces three-dimensional shape using isothamic fringe patterns and digital image processing. The current study presents the method and applies it to images obtained by simulation for error evaluation, as well as to a buckled plate, obtaining excellent results. The method hands itself particularly useful to decrease the errors in the interpretation of the Moiré fringes that can adversely affect the calculations of displacements in pieces containing many concave and convex regions in relatively small areas.
Resumo:
•Introduction •Process Experimental Setup •Experimental Procedure •Experimental Results for Al2024 - T351, Ti6Al4V and AISI 316L - Surface Roughness and Compactation - Residual stresses - Tensile Strength - Fatigue Life •Discussion and Outlook - Prospects for technological applications of LSP
Resumo:
We evaluated the performance of a novel procedure for segmenting mammograms and detecting clustered microcalcifications in two types of image sets obtained from digitization of mammograms using either a laser scanner, or a conventional ""optical"" scanner. Specific regions forming the digital mammograms were identified and selected, in which clustered microcalcifications appeared or not. A remarkable increase in image intensity was noticed in the images from the optical scanner compared with the original mammograms. A procedure based on a polynomial correction was developed to compensate the changes in the characteristic curves from the scanners, relative to the curves from the films. The processing scheme was applied to both sets, before and after the polynomial correction. The results indicated clearly the influence of the mammogram digitization on the performance of processing schemes intended to detect microcalcifications. The image processing techniques applied to mammograms digitized by both scanners, without the polynomial intensity correction, resulted in a better sensibility in detecting microcalcifications in the images from the laser scanner. However, when the polynomial correction was applied to the images from the optical scanner, no differences in performance were observed for both types of images. (C) 2008 SPIE and IS&T [DOI: 10.1117/1.3013544]
Resumo:
Background: Various neuroimaging studies, both structural and functional, have provided support for the proposal that a distributed brain network is likely to be the neural basis of intelligence. The theory of Distributed Intelligent Processing Systems (DIPS), first developed in the field of Artificial Intelligence, was proposed to adequately model distributed neural intelligent processing. In addition, the neural efficiency hypothesis suggests that individuals with higher intelligence display more focused cortical activation during cognitive performance, resulting in lower total brain activation when compared with individuals who have lower intelligence. This may be understood as a property of the DIPS. Methodology and Principal Findings: In our study, a new EEG brain mapping technique, based on the neural efficiency hypothesis and the notion of the brain as a Distributed Intelligence Processing System, was used to investigate the correlations between IQ evaluated with WAIS (Whechsler Adult Intelligence Scale) and WISC (Wechsler Intelligence Scale for Children), and the brain activity associated with visual and verbal processing, in order to test the validity of a distributed neural basis for intelligence. Conclusion: The present results support these claims and the neural efficiency hypothesis.
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The goal of this paper is to study and propose a new technique for noise reduction used during the reconstruction of speech signals, particularly for biomedical applications. The proposed method is based on Kalman filtering in the time domain combined with spectral subtraction. Comparison with discrete Kalman filter in the frequency domain shows better performance of the proposed technique. The performance is evaluated by using the segmental signal-to-noise ratio and the Itakura-Saito`s distance. Results have shown that Kalman`s filter in time combined with spectral subtraction is more robust and efficient, improving the Itakura-Saito`s distance by up to four times. (C) 2007 Elsevier Ltd. All rights reserved.
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Most post-processors for boundary element (BE) analysis use an auxiliary domain mesh to display domain results, working against the profitable modelling process of a pure boundary discretization. This paper introduces a novel visualization technique which preserves the basic properties of the boundary element methods. The proposed algorithm does not require any domain discretization and is based on the direct and automatic identification of isolines. Another critical aspect of the visualization of domain results in BE analysis is the effort required to evaluate results in interior points. In order to tackle this issue, the present article also provides a comparison between the performance of two different BE formulations (conventional and hybrid). In addition, this paper presents an overview of the most common post-processing and visualization techniques in BE analysis, such as the classical algorithms of scan line and the interpolation over a domain discretization. The results presented herein show that the proposed algorithm offers a very high performance compared with other visualization procedures.
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The objective was to study the flow pattern in a plate heat exchanger (PHE) through residence time distribution (RTD) experiments. The tested PHE had flat plates and it was part of a laboratory scale pasteurization unit. Series flow and parallel flow configurations were tested with a variable number of passes and channels per pass. Owing to the small scale of the equipment and the short residence times, it was necessary to take into account the influence of the tracer detection unit on the RID data. Four theoretical RID models were adjusted: combined, series combined, generalized convection and axial dispersion. The combined model provided the best fit and it was useful to quantify the active and dead space volumes of the PHE and their dependence on its configuration. Results suggest that the axial dispersion model would present good results for a larger number of passes because of the turbulence associated with the changes of pass. This type of study can be useful to compare the hydraulic performance of different plates or to provide data for the evaluation of heat-induced changes that occur in the processing of heat-sensitive products. (C) 2011 Elsevier Ltd. All rights reserved.
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The present work reports the porous alumina structures fabrication and their quantitative structural characteristics study based on mathematical morphology analysis by using the SEM images. The algorithm used in this work was implemented in 6.2 MATLAB software. Using the algorithm it was possible to obtain the distribution of maximum, minimum and average radius of the pores in porous alumina structures. Additionally, with the calculus of the area occupied by the pores, it was possible to obtain the porosity of the structures. The quantitative results could be obtained and related to the process fabrication characteristics, showing to be reliable and promising to be used to control the pores formation process. Then, this technique could provide a more accurate determination of pore sizes and pores distribution. (C) 2008 Elsevier Ltd. All rights reserved.
Resumo:
Hydrophilic dentin adhesives are prone to water sorption that adversely affects the durability of resin-dentin bonds. This study examined the feasibility of bonding to dentin with hydrophobic resins via the adaptation of electron microscopy tissue processing techniques. Hydrophobic primers were prepared by diluting 2,2-bis[4(2-hydroxy-3-methacryloyloxy-propyloxy)-phenyl] propane/triethyleneglycol dimethacrylate resins with known ethanol concentrations. They were applied to acid-etched moist dentin using an ethanol wet bonding technique that involved: (1) stepwise replacement of water with a series of increasing ethanol concentrations to prevent the demineralized collagen matrix from collapsing; (2) stepwise replacement of the ethanol with different concentrations of hydrophobic primers and subsequently with neat hydrophobic resin. Using the ethanol wet bonding technique, the experimental primer versions with 40, 50, and 75% resin exhibited tensile strengths which were not significantly different from commercially available hydrophilic three-step adhesives that were bonded with water wet bonding technique. The concept of ethanol wet bonding may be explained in terms of solubility parameter theory. This technique is sensitive to water contamination, as depicted by the lower tensile strength results from partial dehydration protocols. The technique has to be further improved by incorporating elements of dentin permeability reduction to avoid water from dentinal tubules contaminating water-free resin blends during bonding. (c) 2007 Wiley Periodicals, Inc. J Biomed Mater Res 84A: 19-29, 2008.
Resumo:
This is the first paper in a study on the influence of the environment on the crack tip strain field for AISI 4340. A stressing stage for the environmental scanning electron microscope (ESEM) was constructed which was capable of applying loads up to 60 kN to fracture-mechanics samples. The measurement of the crack tip strain field required preparation (by electron lithography or chemical etching) of a system of reference points spaced at similar to 5 mu m intervals on the sample surface, loading the sample inside an electron microscope, image processing procedures to measure the displacement at each reference point and calculation of the strain field. Two algorithms to calculate strain were evaluated. Possible sources of errors were calculation errors due to the algorithm, errors inherent in the image processing procedure and errors due to the limited precision of the displacement measurements. Estimation of the contribution of each source of error was performed. The technique allows measurement of the crack tip strain field over an area of 50 x 40 mu m with a strain precision better than +/- 0.02 at distances larger than 5 mu m from the crack tip. (C) 1999 Kluwer Academic Publishers.
Resumo:
A technique is described to preserve the pigment found in the bodies and the intestine of some brightly coloured and darkly pigmented benedeniine capsalid monogeneans. Previous studies of these pigmented capsalids have proven difficult because the pigmentation usually disappears when the worms are fixed using preservatives containing concentrations of formalin over 5% and/or ethanol, acetic acid, chromic acid, picric acid and mercuric chloride. The technique developed here uses a fixative comprising glycerol, acetone and formalin (GAF). After fixation under light coverslip compression for three minutes, specimens are transferred to absolute acetone for three minutes and cleared in a mixture of nine parts cedar wood oil and one part absolute acetone before mounting in Canada balsam. Processing must be carried out quickly, as these chemicals will cause the pigments to fade if the specimens are exposed to them for too long. Pigmented benedeniines processed using this technique retain the distribution, intensity and colour observed in live worms. The colour and distribution of pigmentation in monogeneans may be of taxonomic importance and this technique aids preparation of whole-mounts suitable for registration as type-material.