907 resultados para Hierarchy and topology
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The research described in this thesis was motivated by the need of a robust model capable of representing 3D data obtained with 3D sensors, which are inherently noisy. In addition, time constraints have to be considered as these sensors are capable of providing a 3D data stream in real time. This thesis proposed the use of Self-Organizing Maps (SOMs) as a 3D representation model. In particular, we proposed the use of the Growing Neural Gas (GNG) network, which has been successfully used for clustering, pattern recognition and topology representation of multi-dimensional data. Until now, Self-Organizing Maps have been primarily computed offline and their application in 3D data has mainly focused on free noise models, without considering time constraints. It is proposed a hardware implementation leveraging the computing power of modern GPUs, which takes advantage of a new paradigm coined as General-Purpose Computing on Graphics Processing Units (GPGPU). The proposed methods were applied to different problem and applications in the area of computer vision such as the recognition and localization of objects, visual surveillance or 3D reconstruction.
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Apesar de décadas de estudos, as opiniões são controversas. Não existe uma opinião comum entre os pesquisadores sobre o que é e como ocorre a motivação, a satisfação e a insatisfação no trabalho. As condições físicas dos serviços são um factor primordial para a motivação, satisfação ou insatisfação do trabalhador, assim como o tipo de liderança existente no mesmo. Ao longo da nossa história tem-se assistido a muitos exemplos de liderança, uns mais, outros menos eficazes. A satisfação no trabalho é um estado afectivo resultante da apreciação das características percebidas do trabalho e da organização. Neste contexto de mudanças na administração pública em geral e na área da saúde em particular, surge este estudo em contexto hospitalar, motivado pela necessidade de conhecer a satisfação dos enfermeiros de um Centro Hospitalar de Lisboa e a relação com algumas variáveis sócio demográficas. Optou-se pelo paradigma quantitativo, numa amostra de 122 inquiridos pertencentes a um grupo de profissionais de enfermagem de um Hospital Central de Lisboa. Para a elaboração da parte empírica utilizou-se o método por questionário de escolha múltipla. Os objectivos definidos: Objectivo Geral: perceber o nível de motivação/ satisfação dos enfermeiros relativamente à profissão ao serviço e à hierarquia. Objectivos específicos: Identificar o nível de satisfação/motivação dos enfermeiros dos serviços estudados relativamente à profissão, em função das variáveis sociodemográficas. - Caracterizar os aspectos com os quais os enfermeiros têm maior e menor satisfação relacionados com a profissão, serviço e hierarquia. - Identificar se existe relação entre o nível de motivação/satisfação e os sintomas físicos sentidos. Os participantes da amostra são, maioritariamente do sexo feminino, a média de idades é de 32 anos, grande percentagem já tem como habilitações profissionais a licenciatura, têm entre 1 e 28 anos de profissão e 1 e 28 anos no serviço actual, 17,2% exercem funções de chefia. Grande percentagem da amostra tem como horário semanal de trabalho 35 horas e trabalham em horário rotativo. Os enfermeiros são profissionais que mostram insatisfação relativamente à profissão e hierarquia e moderada satisfação relativamente aos serviços. A satisfação dos enfermeiros quanto à profissão altera-se de acordo com o horário de trabalho, vínculo à instituição e os sentimentos que os mesmos têm relativamente ao trabalho. A satisfação dos enfermeiros relativamente ao serviço altera-se consoante o tempo de profissão e com os sentimentos que os profissionais apresentam relativamente ao trabalho. Quanto à satisfação dos enfermeiros relativamente à hierarquia altera-se dependendo da idade dos profissionais, do tempo de profissão e do serviço onde desempenham. Relativamente à satisfação geral com o trabalho, esta pode alterar dependendo da idade, do tempo de profissão, do serviço onde desempenham funções e dos sentimentos dos profissionais relativamente ao trabalho. De salientar que ao analisarmos os serviços estudados separadamente concluímos que os enfermeiros do serviço de urgência são profissionais muito insatisfeitos com a hierarquia e os enfermeiros da Unidade de Urgência Médica são profissionais pouco satisfeitos, mas apesar de tudo satisfeitos com a hierarquia. ABSTRACT; Behind decades of studies, the opinions are controversial. There is a common opinion among researchers about what is and how is the motivation, satisfaction and dissatisfaction at work. The physical conditions of services are a major factor in motivation, satisfaction or dissatisfaction of the worker and the type of leadership exists in it. Throughout our history have seen many examples of leadership, some more, some less effective. Job satisfaction is an affective state resulting from the assessment of the perceived characteristics of work and organization. ln this context of changes in public administration in general and in health in particular, this study appears in the hospital setting, motivated by the need to know the satisfaction of nurses in a Hospital in Lisbon and the relationship with sociodemographic variables. We chose the quantitative paradigm in a sample of 122 respondents belonging to a group of nursing professionals in a central hospital in Lisbon. ln developing the empirical part we used the method for multiple-choice test. The objectives: General Objective: To understand the level of motivation I satisfaction of nurses for the profession and the service hierarchy. Specific objectives: To identify the level of satisfaction I motivation of nursing service studied for the profession, according to the socio-demographic variables. - Characterize the points with which nurses have the highest and lowest satisfaction related to the profession, service and hierarchy. - To identify if there is a relationship between the level of motivation I satisfaction and physical symptoms felt. The sample participants are mostly female, average age is 32 years, a large percentage already has the professional qualifications of the degree, are between and 28 years of occupation and 1 and 28 in the current service, 17.2 % hold positions of leadership. A great percentage of the sample has the working week and working 35 hours on rotating schedule. Nurses are professionals who show dissatisfaction with the profession and the hierarchy and moderately satisfied for the services, the latter fact can be justified by what is possible when the organization professionals are available and perform functions in service to their liking and they like to work. The satisfaction of nurses as the profession changes according to working hours, commitment to the institution and the feelings they have for the work. The satisfaction of nurses for the service changes depending on the length of service and with the feelings that professionals are on the job. The satisfaction of nurses from the hierarchy will change depending on the age of professionals, time and professional service where they play. For the overall satisfaction with the work, this may change depending on age, length of employment, where the service functions and the feelings of the professionals for the job. Note that when analyzing the services studied separately concluded that the nurses in the emergency department professionals are very unhappy with the hierarchy and the nurses of the Unit of Emergency Medical professionals are somewhat satisfied but still happy
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Letras, Programa de Pós-Graduação em Literatura, 2016.
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Based on the empirical comparative study between two churches from Pentecostal guidance - both located in Parnamirim/RN - and supported on a dialogic interaction between my interlocutors and theoretical references, I proposed me to reflect about how this protestant segment represents and articulates questions such as gender and power relationships, and the daily impact of that in their followers life. In other words, this dissertation aims to understand the reason of the asymmetry attributed to male and female, especially in what concerns the distribution of ecclesiastic works and the authority given to male, as well as the implication of this reality in the reconfiguration of morality and religious praxis in daily life of individuals and involved groups. From this perspective, this work was divided in three chapters, in which I investigate the tension/relationship between faith and secularism, for from this question on concessions and/or prohibitions related to the limits and involvement of the followers with the world and with the very Pentecostal ethos arise. I also analyze here aspects concerning to both ecclesiastic hierarchy and power, with the objective of elucidating how it occurs, what kind of criteria and implications they consider as well as about the nature of the religious labor division between men and women and, finally, I try to understand how the conversion/adhesion of members is reflected in the redefinitions of gender and its relationship between the ecclesiastical and domestic spaces. The diligence and energy spent in this work is in the hope that its fruits can corroborate in the expansion of anthropological knowledge which, in this particular case, involves the Brazilian Pentecostal phenomenon
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In design and manufacturing, mesh segmentation is required for FACE construction in boundary representation (BRep), which in turn is central for featurebased design, machining, parametric CAD and reverse engineering, among others -- Although mesh segmentation is dictated by geometry and topology, this article focuses on the topological aspect (graph spectrum), as we consider that this tool has not been fully exploited -- We preprocess the mesh to obtain a edgelength homogeneous triangle set and its Graph Laplacian is calculated -- We then produce a monotonically increasing permutation of the Fiedler vector (2nd eigenvector of Graph Laplacian) for encoding the connectivity among part feature submeshes -- Within the mutated vector, discontinuities larger than a threshold (interactively set by a human) determine the partition of the original mesh -- We present tests of our method on large complex meshes, which show results which mostly adjust to BRep FACE partition -- The achieved segmentations properly locate most manufacturing features, although it requires human interaction to avoid over segmentation -- Future work includes an iterative application of this algorithm to progressively sever features of the mesh left from previous submesh removals
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This study intends to enhance the existing knowledge concerning the patterns of the uses of space for low cost housing in Parnamirim, Rio Grande do Norte, Brazil, by way of comparative morphological studies in spatial arrangements and articulations regarding three distinct, however inter-related, sets of social housing: (1) a development comprising 21 self-built houses erected on public routes and illegal plots within a tract of land originally designed to be an industrial development: (2) architect-designed houses built by the public authority in order to accommodate the previous 21 (plus a few additions) families occupying the self-built dwellings, and (3) modifications performed by dwellers on a total of those 24 houses built by the public authority after an occupation period of one year. The predominant uses of each room within the self-built and modified houses were represented in ground plan, based on empirical observation, surveys with dwellers and the use of analytical procedures of morphologic analysis of nature predominantly geometric (specific) and topology (space syntax analysis). A scale of priorities was identified in relation to the uses of each room, its geometrical arrangement (adjacency, front/back relations etc), and underlying structures (connectivity, depth and spatial integration) in order to establish congruencies and non-congruencies between a social-cultural order embedded in the self-built domestic space and the design logic contained in the houses offered by official agencies. The comparative analysis points towards the convivial existence of two tendencies: one that seems to reinforce a design logic inasmuch as the additions and modifications performed by the dwellers do not alter but even emphasize the original configuration of the designed houses, and another one in which those patterns are subverted in accordance with a logic which, to a lesser or greater degree, coincides with that of the self-built dwellings
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Este estudo tem como objetivo definir linhas orientadoras para as estruturas organizacionais em bibliotecas universitárias portuguesas e baseia-se numa investigação que fez uso de métodos diversificados, tanto quantitativos (em extensão), como qualitativos (em profundidade), e cotejou os dados assim obtidos com as práticas mais inovadoras em bibliotecas de diversos países do mundo. Foi feito o enquadramento teórico, para temas relacionados com os da investigação, como as teorias da gestão, as estruturas organizacionais, a liderança, a motivação, a comunicação e o processo de mudança nas organizações. Considerando o meio onde se integram estas bibliotecas, identificaram-se os principais aspetos da política educativa no ensino superior europeu e português. A revisão da literatura permitiu recolher informação sobre algumas tendências mais recentes nas bibliotecas universitárias, em geral e em Portugal. Foram identificadas as tipologias de estruturas organizacionais, as transformações que as mesmas têm sofrido noutros países e que soluções foram encontradas. A partir dos dados recolhidos com o questionário, caracterizaram-se estas bibliotecas portuguesas e os resultados indicam que há uma grande diversidade e que, em grande parte as suas estruturas organizacionais foram alteradas. Com o estudo de caso, detalharam-se aspetos dessas alterações. Concluiu-se que, com as alterações no ensino superior, as bibliotecas podem ter um papel mais ativo no processo de ensino-aprendizagem. As alterações em estruturas organizacionais de bibliotecas universitárias portuguesas ocorreram, na sua grande parte, por razões legais e houve participação das chefias das bibliotecas e dos técnicos superiores especializados em ciências da informação. As novas estruturas organizacionais procuram adaptar-se às transformações externas e internas, optando por estruturas mais flexíveis que incentivam a participação de todos os funcionários na inovação e tomadas de decisão. Como linhas orientadoras, foram indicados um conjunto de princípios por não ser possível um modelo ideal a aplicar em todas as bibliotecas. Cada caso encontrará uma solução que deverá ser continuamente analisada e adaptada à realidade; Organizational structure of university libraries in Portugal Abstract: The purpose of this study is to define guidelines for the organizational structures of Portuguese university libraries and it is based on a research that used as quantitative (in range) as qualitative (in depth) methods and compared the findings with the most innovative practices in libraries all over the world. An approach was made to the theoretical areas of management, organizational structures, leadership, motivation, communication and the process of change in organizations. Considering that these libraries act in higher education institutions it was referred the education policy for higher education, in Europe and in Portugal. The literature review allowed collecting information about the more recent tendencies of the university libraries in general and in Portugal. The organizational structures models were identified as their changes and solutions. From the data from the questionnaire the Portuguese university libraries were described and the results show there is a great variety among them and most of them have transformed their organizational structures. The case study allowed obtaining more information about the process of change in the three selected libraries. It was concluded that, with the changes of higher education, the libraries can play a more active role in the teaching and learning process. The changes of the organizational structures in the Portuguese university libraries occurred mostly for legal reasons and the top of the libraries hierarchy and librarians participated. With the new organizational structures libraries have made all the efforts to adapt to the external and internal transformations with more flexible structures encouraging all staff to participate with ideas and to take part in the decision process. For the guidelines it was pointed out a set of principles to follow as it is not possible to have an ideal model to apply to all the libraries. Each library must find a solution that will be continually analyzed and adapted.
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Persistent homology is a branch of computational topology which uses geometry and topology for shape description and analysis. This dissertation is an introductory study to link persistent homology and graph theory, the connection being represented by various methods to build simplicial complexes from a graph. The methods we consider are the complex of cliques, of independent sets, of neighbours, of enclaveless sets and complexes from acyclic subgraphs, each revealing several properties of the underlying graph. Moreover, we apply the core ideas of persistence theory in the new context of graph theory, we define the persistent block number and the persistent edge-block number.
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By means of continuous topology optimization, this paper discusses the influence of material gradation and layout in the overall stiffness behavior of functionally graded structures. The formulation is associated to symmetry and pattern repetition constraints, including material gradation effects at both global and local levels. For instance, constraints associated with pattern repetition are applied by considering material gradation either on the global structure or locally over the specific pattern. By means of pattern repetition, we recover previous results in the literature which were obtained using homogenization and optimization of cellular materials.
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Sensors and actuators based on piezoelectric plates have shown increasing demand in the field of smart structures, including the development of actuators for cooling and fluid-pumping applications and transducers for novel energy-harvesting devices. This project involves the development of a topology optimization formulation for dynamic design of piezoelectric laminated plates aiming at piezoelectric sensors, actuators and energy-harvesting applications. It distributes piezoelectric material over a metallic plate in order to achieve a desired dynamic behavior with specified resonance frequencies, modes, and enhanced electromechanical coupling factor (EMCC). The finite element employs a piezoelectric plate based on the MITC formulation, which is reliable, efficient and avoids the shear locking problem. The topology optimization formulation is based on the PEMAP-P model combined with the RAMP model, where the design variables are the pseudo-densities that describe the amount of piezoelectric material at each finite element and its polarization sign. The design problem formulated aims at designing simultaneously an eigenshape, i.e., maximizing and minimizing vibration amplitudes at certain points of the structure in a given eigenmode, while tuning the eigenvalue to a desired value and also maximizing its EMCC, so that the energy conversion is maximized for that mode. The optimization problem is solved by using sequential linear programming. Through this formulation, a design with enhancing energy conversion in the low-frequency spectrum is obtained, by minimizing a set of first eigenvalues, enhancing their corresponding eigenshapes while maximizing their EMCCs, which can be considered an approach to the design of energy-harvesting devices. The implementation of the topology optimization algorithm and some results are presented to illustrate the method.
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The ability to control both the minimum size of holes and the minimum size of structural members are essential requirements in the topology optimization design process for manufacturing. This paper addresses both requirements by means of a unified approach involving mesh-independent projection techniques. An inverse projection is developed to control the minimum hole size while a standard direct projection scheme is used to control the minimum length of structural members. In addition, a heuristic scheme combining both contrasting requirements simultaneously is discussed. Two topology optimization implementations are contributed: one in which the projection (either inverse or direct) is used at each iteration; and the other in which a two-phase scheme is explored. In the first phase, the compliance minimization is carried out without any projection until convergence. In the second phase, the chosen projection scheme is applied iteratively until a solution is obtained while satisfying either the minimum member size or minimum hole size. Examples demonstrate the various features of the projection-based techniques presented.
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This article presents a systematic and logical study of the topology optimized design, microfabrication, and static/dynamic performance characterization of an electro-thermo-mechanical microgripper. The microgripper is designed using a topology optimization algorithm based on a spatial filtering technique and considering different penalization coefficients for different material properties during the optimization cycle. The microgripper design has a symmetric monolithic 2D structure which consists of a complex combination of rigid links integrating both the actuating and gripping mechanisms. The numerical simulation is performed by studying the effects of convective heat transfer, thermal boundary conditions at the fixed anchors, and microgripper performance considering temperature-dependent and independent material properties. The microgripper is fabricated from a 25 mm thick nickel foil using laser microfabrication technology and its static/dynamic performance is experimentally evaluated. The static and dynamic electro-mechanical characteristics are analyzed as step response functions with respect to tweezing/actuating displacements, applied current/power, and actual electric resistance. A microgripper prototype having overall dimensions of 1mm (L) X 2.5mm (W) is able to deliver the maximum tweezing and actuating displacements of 25.5 mm and 33.2 mm along X and Y axes, respectively, under an applied power of 2.32 W. Experimental performance is compared with finite element modeling simulation results.
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Tailoring specified vibration modes is a requirement for designing piezoelectric devices aimed at dynamic-type applications. A technique for designing the shape of specified vibration modes is the topology optimization method (TOM) which finds an optimum material distribution inside a design domain to obtain a structure that vibrates according to specified eigenfrequencies and eigenmodes. Nevertheless, when the TOM is applied to dynamic problems, the well-known grayscale or intermediate material problem arises which can invalidate the post-processing of the optimal result. Thus, a more natural way for solving dynamic problems using TOM is to allow intermediate material values. This idea leads to the functionally graded material (FGM) concept. In fact, FGMs are materials whose properties and microstructure continuously change along a specific direction. Therefore, in this paper, an approach is presented for tailoring user-defined vibration modes, by applying the TOM and FGM concepts to design functionally graded piezoelectric transducers (FGPT) and non-piezoelectric structures (functionally graded structures-FGS) in order to achieve maximum and/or minimum vibration amplitudes at certain points of the structure, by simultaneously finding the topology and material gradation function. The optimization problem is solved by using sequential linear programming. Two-dimensional results are presented to illustrate the method.
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Discussion opposing the Theory of the Firm to the Theory of Stakeholders are contemporaneous and polemical. One focal point of such debates refers to which objective-function companies, should choose, whether that of the shareholders or that of the stakeholders, and whether it is possible to opt for both simultaneously. Several empirical studies. have attempted-to test a possible correlation between both functions, and there has not been any consensus-so far. The objective of the present research is to examine a gap in such discussions: is there (or not) a subordination of the stakeholders` objective-function to that of the shareholders? The research is empirical,and analytical and employs quantitative methods. Hypotheses were tested and data analyzed by using non-parametrical (chi-square test) and parametrical procedures (frequency. correlation `coefficient). Secondary data was collected from he Economitica database and from the Brazilian Institute of Social and-Economic Analyses (IBASE) website, relative to public companies that have published their Social Balance Statements following the IBASE model from 1999 to 2006, whose sample amounted to 65 companies; In order to assess the objective-function of shareholders a proxy was created based on the following three indices: ROE (return on equity), EnterpriseValue and Tobin`s Q. In order to assess the objective-function of stakeholders a proxy was created by employing the following IBASE social balance indices: internal ones (ISI), external ones (ISE), and environmental ones (IAM). The results have shown no evidence of subordination of stakeholders` objective-function to that of the shareholders in analyzed companies, negating initial expectations and calling for deeper investigation of results. Its main conclusion, which states that the attempted subordination does not take place, is limited to the sample herein investigated and calls for ongoing research aiming at improvements which may lead to sample enlargement and, as a consequence, may make feasible the application of other statistical techniques which may yield a more thorough, analysis of the studied phenomehon.
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Most studies of tiller development have not related the physiological and morphological features of each calm to its subsequent fertility. This introduced problems when trying to account for the effects of tillering on yield in crop models. The objective of this study was to detect the most likely early determinants of tiller fertility in sorghum by identifying hierarchies for emergence, fertility and grain number of tillers over a wide range of assimilate availabilities. Emergence, phenology, leaf area development and dry weight partitioning were quantified weekly for individual tillers and main culms of tillering and uniculm plants grown at one of four densities, from two to 16 plants m(-2). For a given plant in any given density, the same tiller hierarchy applied for emergence of tillers, fertility of the emerged tillers and their subsequent grain number. These results were observed over a range of tiller fertility rates (from 7 to 91%), fertile tiller number per plant at maturity (from 0.2 to 4.7), and tiller contribution to grain yield (from 5 to 78%). Tiller emergence was most probably related to assimilate supply and light quality. Development, fertility and contribution to yield of a specific tiller were highly dependent on growing conditions at the time of tiller emergence, particularly via early leaf area development of the tiller, which affected its subsequent leaf area accumulation. Assimilate availability in the main culm at the time of tiller emergence was the most likely early determinant of subsequent tiller fertility in this study. (C) 2002 Annals of Botany Company.