968 resultados para Saldanha, João Carlos de Saldanha de Oliveira e Daun, Duque de, 1790-1876.
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This work proposes a formulation for optimization of 2D-structure layouts submitted to mechanic and thermal shipments and applied an h-adaptive filter process which conduced to computational low spend and high definition structural layouts. The main goal of the formulation is to minimize the structure mass submitted to an effective state of stress of von Mises, with stability and lateral restriction variants. A criterion of global measurement was used for intents a parametric condition of stress fields. To avoid singularity problems was considerate a release on the stress restriction. On the optimization was used a material approach where the homogenized constructive equation was function of the material relative density. The intermediary density effective properties were represented for a SIMP-type artificial model. The problem was simplified by use of the method of finite elements of Galerkin using triangles with linear Lagrangian basis. On the solution of the optimization problem, was applied the augmented Lagrangian Method, that consists on minimum problem sequence solution with box-type restrictions, resolved by a 2nd orderprojection method which uses the method of the quasi-Newton without memory, during the problem process solution. This process reduces computational expends showing be more effective and solid. The results materialize more refined layouts with accurate topologic and shape of structure definitions. On the other hand formulation of mass minimization with global stress criterion provides to modeling ready structural layouts, with violation of the criterion of homogeneous distributed stress
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The growing demand in the use of composite materials necessitates a better understanding its behavior to many conditions of loading and service, as well as under several ways of connections involved in mechanisms of structural projects. It is know that most of the structural elements are designed with presence of geometric discontinuities (holes, notches, etc) in their longitudinal sections and / or transversals, and that these discontinuities affect the mechanical response of these elements. This work has aims to analyze a study of the mechanical response, when in the presence geometric discontinuity, of polymer matrix composite laminates (orthophthalic polyester) to the uniaxial tensile test. The geometric discontinuity is characterized by the presence of a center hole in the transversal section of the composite. In this study, different kinds of stacking sequences are tested, with and without the presence of the hole, so as to provide better understanding of the mechanical properties. This sense, two laminates were studied: the first is only reinforced by with seven layers short mats of fiberglass-E (CM) and the second where the reinforcement of fiberglass-E comes in the form of bidirectional fabric (CT), with only four layers. The laminate CT has the presence of anisotropy (sense of continuous fibers with respect to the applied load) as the main parameter influencing its mechanical behavior, behavior this, not observed for the CM. In addition to the mechanical properties was also studied the fracture characteristics developed in each composite laminated. The results also showed that the presence of the hole in the transversal section decreased the ultimate strength of laminates and changed the final characteristic of fracture in all kinds of composite laminated studied
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In recent years there has been a significant growth in technologies that modify implant surfaces, reducing healing time and allowing their successful use in areas with low bone density. One of the most widely used techniques is plasma nitration, applied with excellent results in titanium and its alloys, with greater frequency in the manufacture of hip, ankle and shoulder implants. However, its use in dental implants is very limited due to high process temperatures (between 700 C o and 800 C o ), resulting in distortions in these geometrically complex and highly precise components. The aim of the present study is to assess osseointegration and mechanical strength of grade II nitrided titanium samples, through configuration of hollow cathode discharge. Moreover, new formulations are proposed to determine the optimum structural topology of the dental implant under study, in order to perfect its shape, make it efficient, competitive and with high definition. In the nitriding process, the samples were treated at a temperature of 450 C o and pressure of 150 Pa , during 1 hour of treatment. This condition was selected because it obtains the best wettability results in previous studies, where different pressure, temperature and time conditions were systematized. The samples were characterized by X-ray diffraction, scanning electron microscope, roughness, microhardness and wettability. Biomechanical fatigue tests were then conducted. Finally, a formulation using the three dimensional structural topology optimization method was proposed, in conjunction with an hadaptive refinement process. The results showed that plasma nitriding, using the hollow cathode discharge technique, caused changes in the surface texture of test specimens, increases surface roughness, wettability and microhardness when compared to the untreated sample. In the biomechanical fatigue test, the treated implant showed no flaws, after five million cycles, at a maximum fatigue load of 84.46 N. The results of the topological optimization process showed well-defined optimized layouts of the dental implant, with a clear distribution of material and a defined edge
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The topology optimization problem characterize and determine the optimum distribution of material into the domain. In other words, after the definition of the boundary conditions in a pre-established domain, the problem is how to distribute the material to solve the minimization problem. The objective of this work is to propose a competitive formulation for optimum structural topologies determination in 3D problems and able to provide high-resolution layouts. The procedure combines the Galerkin Finite Elements Method with the optimization method, looking for the best material distribution along the fixed domain of project. The layout topology optimization method is based on the material approach, proposed by Bendsoe & Kikuchi (1988), and considers a homogenized constitutive equation that depends only on the relative density of the material. The finite element used for the approach is a four nodes tetrahedron with a selective integration scheme, which interpolate not only the components of the displacement field but also the relative density field. The proposed procedure consists in the solution of a sequence of layout optimization problems applied to compliance minimization problems and mass minimization problems under local stress constraint. The microstructure used in this procedure was the SIMP (Solid Isotropic Material with Penalty). The approach reduces considerably the computational cost, showing to be efficient and robust. The results provided a well defined structural layout, with a sharpness distribution of the material and a boundary condition definition. The layout quality was proporcional to the medium size of the element and a considerable reduction of the project variables was observed due to the tetrahedrycal element
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The aim of this study is to create an artificial neural network (ANN) capable of modeling the transverse elasticity modulus (E2) of unidirectional composites. To that end, we used a dataset divided into two parts, one for training and the other for ANN testing. Three types of architectures from different networks were developed, one with only two inputs, one with three inputs and the third with mixed architecture combining an ANN with a model developed by Halpin-Tsai. After algorithm training, the results demonstrate that the use of ANNs is quite promising, given that when they were compared with those of the Halpín-Tsai mathematical model, higher correlation coefficient values and lower root mean square values were observed
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The development of non-linear controllers gained space in the theoretical ambit and of practical applications on the moment that the arising of digital computers enabled the implementation of these methodologies. In comparison with the linear controllers more utilized, the non -linear controllers present the advantage of not requiring the linearity of the system to determine the parameters of control, which permits a more efficient control especially when the system presents a high level of non-linearity. Another additional advantage is the reduction of costs, since to obtain the efficient control through linear controllers it is necessary the utilization of sensors and more refined actuators than when it is utilized a non-linear controller. Among the non-linear theories of control, the method of control by gliding ways is detached for being a method that presents more robustness, before uncertainties. It is already confirmed that the adoption of compensation on the region of residual error permits to improve better the performance of these controllers. So, in this work it is described the development of a non-linear controller that looks for an association of strategy of control by gliding ways, with the fuzzy compensation technique. Through the implementation of some strategies of fuzzy compensation, it was searched the one which provided the biggest efficiency before a system with high level of nonlinearities and uncertainties. The electrohydraulic actuator was utilized as an example of research, and the results appoint to two configurations of compensation that permit a bigger reduction of the residual error
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Este artigo avalia os resultados do processo de reestruturação da indústria brasileira de máquinas têxteis, originado pelas reformas econômicas liberalizantes iniciadas no final dos anos 1980 e início dos 1990 e pelas medidas macroeconômicas que deram sustentação ao Plano Real, a partir de julho de 1994. Inicialmente, fazemos uma avaliação teórica das fontes do conhecimento e das formas de capacitação tecnológica nessa indústria. A seguir, expomos brevemente as principais características da indústria de máquinas têxteis em âmbito global. Posteriormente, direcionando a discussão para o caso brasileiro, apresentamos as especificidades da indústria têxtil, usuária daqueles bens, e do próprio setor de máquinas nacional. Através dos fluxos de comércio exterior do Brasil entre 1990 e 2004 e da variação do valor médio (US$ FOB/KG) desses fluxos, o artigo examina as mudanças estruturais, tecnológicas e, por conseguinte, na competitividade, que culminaram na transformação da indústria brasileira de máquinas têxteis, em termos de dimensão (escala) e escopo, e em uma nova inserção internacional, agora mais especializada e subordinada.
Integração de redes GNSS: uma proposta metodológica de densificação da rede SIRGAS na América do Sul
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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This master thesis is an overview of how the Egyptian writing became a ruin, and then was mythunderstood by the Western culture through speculations based on its figurative appeal or by its magical nature this invention results not only in new idea of writing, but also in many graphical experiments which take part in the creation of the Renaissance and Baroque visual identity
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The inventory management in hospitals is of paramount importance, since the supply materials and drugs interruption can cause irreparable damage to human lives while excess inventories involves immobilization of capital. Hospitals should use techniques of inventory management to perform replenishment in shorter and shorter intervals, in order to reduce inventories and fixed assets and meet citizens requirements properly. The inventory management can be an even bigger problem for public hospitals, which have restrictions on the use of resources and decisionmaking structure more bureaucratized. Currently the University Hospital Onofre Lopes (HUOL) uses a periodic replacement policy for hospital medical supplies and medicines, which involves one moment surplus stock replenishment, the next out of stock items. This study aims to propose a system for continuous replenishment through order point for inventory of medical supplies and medicines to the hospital HUOL. Therefore, a literature review of Federal University Hospitals Management, Logistics, Inventory Management and Replenishment System in Hospitals was performed, emphasizing the demand forecast, classification or ABC curve and order point system. And also, policies of inventory management and the current proposal were described, dealing with profile of the mentioned institution, the current policy of inventory management and simulation for continuous replenishment order point. For the simulation, the sample consisted of 102 and 44 items of medical and hospital drugs, respectively, selected using the ABC classification of inventory, prioritizing items of Class A, which contains the most relevant items in added value, representing 80 % of the financial value in 2012 fiscal year. Considering that it is a public organization, subject to the laws, we performed two simulations: the first, following the signs for inventory management of Instruction No. 205 (IN 205 ), from Secretary of Public Administration of the Presidency ( SEDAP / PR ), and the second, based on the literature specializing in inventory management hospital. The results of two simulations were compared to the current policy of replenishment system. Among these results are: an indication that the system for continuous replenishment reorder point based on IN 205 provides lower levels of safety stock and maximum stock, enables a 17% reduction in the amount spent for the full replenishment of inventories, in other words, decreasing capital assets, as well as reduction in stock quantity, also the simulation made from the literature has indicated parameters that prevent the application of this technique to all items of the sample. Hence, a change in inventory management of HUOL, with the application of the continuous replenishment according to IN 205, provides a significant reduction in acquisition costs of medical and hospital medicine
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One of the largest problems of the present time resulting from the economic globalization and the modern technology, of the point of view of the biological rhytms of our organism, it is offering services and production of goods available in 24 o'clock, that it demands organized workers in several work schedules besides the hours of the day. Those schedules cause a series of biopsychosocial consequences in the worker's health, in function of circadian, homeostatic and psychosocial alterations. Accordingly, the aim of this study was to accomplish an evaluation of the effects of several works schedules in the pattern of the sleep wake cycle, anxiety, stress and in the health. We counted with a sample of 274 workers subdivided in 49 daytime worker groups and 225 workers in different shift work schedules with different speeds (rotating shift group, slower day shift group, faster day shift group). From the results analysis it is verified irregularities of the daily activities, stress and alterations in the workers' health in all schedules. It was also verified thata the workers thata presented irregularities in the daily activities were the mroe stressed. On the other hand, the shift works were considered more ansious and associated with bad sleep quality. It was verified that the workers with bad sleep quality were those presented larger levels of dispocional anxiety. There was no statistically significant correlation between bad sleep quality and irregular daily lifestyle. However, it can be affirmed thata shift work schendules doesn't are the main determinant for the circadian alterations, but the answers of the individuals to the shifts work; and that the inadequate behavioural strategies to work with the effects of the shift schedules. In conclusion, individual strategies related to the coping of the work in shift (adaptation and tolerance) should be extolled as indispensable tool in the ergonomic evaluation of the work
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Knowledge of quality of life is a very complex and rich in cultural and subjective dimensions, understood in a broad sense and multivariate theme. Considering the rural areas from agriculture, it is observed that the production standard defines significant changes in the environmental context and the quality of life of rural workers. To explain the relationship between quality of life and Family Organic Agriculture, we sought to analyze the quality of life of the organic family farmer, after change in agricultural management. The research, based on a procedure exploratory study supported the articulation theoretically constructed, showed their relevance and allowed to delimit with greater security, the central question of work. The WHOQOL - 100 treated the instrument of research on quality of life that directed the field study with organic farmers from the town of Lagoa Seca / PB. Farmers and family members are from rural regions Almeida, Alvinho, Lagoa de Barro, Lagoa Gravatá, Oiti and Pau Ferro. The average time is 39 years farming and organic family farm is 16 years. In the analysis work was found that the process of production of vegetables and fruits is divided into 08 steps and with respect to workloads observations showed the presence of: physical loads, mechanical stresses, psychological burden and ergonomic factors. Most farmers reported symptoms were fatigue and cramps in the legs . Regarding the quality of life was noticed that the Psychological Domain contributed positively to the quality of life with mean and standard deviation (17.83 ± 12.78) and Domain Environment negatively contributing to the quality of life of this group (9.00 ± 6.82). We conclude that the practice of Family Organic Agriculture should be seen as an effective strategy in promoting quality of life and social values in between, since it presents environmental sustainability with regard to life and socio-cultural diversity of populations
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This work presents the processes and the results of a research concerning the affectivity in children suffering from the Down´s Syndrome (DS). The relevance of the study is justified due to the need of the development of researches, in the area of psychological evaluation of people who suffers from Down´s Syndrome (DS), that are backed by the use of appropriate instruments for such purpose. The thematic discussed focuses the characteristics of the affectivity of children suffering from Down´s Syndrome. Affectivity, conceptually, is considered a wide phenomenon, including several aspects such as emotions, passions, anxiety, anguish, sadness, happiness and even the pleasure sensations and pain. The general objective of the study consisted of investigating the manifestation of the affectivity in children and young with Down´s Syndrome and the parents´ and educators´ perception concerning the expression of the affectivity in the behavior and in the social activities. The specific objectives were: to identify the parents' perceptions about the several manifestations of indicative behaviors of affectivity; to verify in the social atmosphere, outside home, through the teachers' perception, the several forms and intensities of the expression of the affectivity; and, to make possible the use of the technique of Zulliger (Z-test) in people with Down´s Syndrome. 70 (seventy) children and young with Down´s Syndrome participated in the research, in the age group from 04 to 26 years old, which are attended by Institutions of Paraíba and of Rio Grande do Norte. The instruments used were two questionnaires, applied with the parents and teachers, and the projective technique, Z-test, applied, individually, with the children and young with Down´s Syndrome. For analysis of the data of the questionnaires, the program Trideux-Mots was used, with the intention of selecting the main outstanding words for the parents and teachers concerning the expression of the children's affectivity and young with Down´s Syndrome. For so much, it was organized a database that was processed by that program and, soon after, interpreted through the Factorial Analysis by Correspondence (AFC), looking for to clear the modalities of presented answers in an organized way, through a graph. The data of the Z-test were analyzed, taking in consideration the need to characterize the aspects of the affectivity and the elaboration of specific norms for this sample type, through normalized scores. In agreement with the data presented by Tri-deux-Mots, it was observed that in the affective behavior and in the relationship with the other, home and in the school, the children and young with Down´s Syndrome they express your affectivity through positive and negative characteristics, in the same way that any other child that doesn't have to syndrome. The Z-test made possible initial elements to work with that population, however it is necessary that grow other researches with the intention of investigating the reason of the answers they present not the specific categories that you/they are related to the affectivity, since it was well-known the diversity of affective characteristics presented by the researched group
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Introduction: This work intents to characterize behavioral indicators of tack to the hemodialysis treatment in a sample of carrying patients of chronic kidney failure (CKF) in the great Natal/RN. The therapeutical adherence represents the agreement degree between the patient behavior and the health team lapsings. The CKF is the gradual and irreversible loss of the renal function, being the hemodialysis treatment an important alternative to assist or to substitute the kidneys. Method: The sample consisted in 80 chronic kidney patients in hemodialysis treatment in two located clinical centers in the region of the great Natal, RN. It was used as instruments (a) a protocol of clinical data collection, (b) the Millon Index of Personality Styles (MIPS) and (c) a script of halfstructuralized interview. Results: The results show a balance between the genders (51% of female and 48.8% of the male sex), average age and equal average time of dialysis respectively to the 43,4 years (±13,25 years) and 22,04 years (±4,24 years). The marital status of half of the sample is married, predominating basic education (43.6%) and a familiar income until a minimum wage (43.8%). It had been defined six physicianlaboratorial indicators to evaluate the therapeutical adherence, further the use of the evaluation of the health team and the patient themselves. Thus, there was an average adherence around 55.97% of the sample ±18.37%). However only between selfassessment of the patients about the adherence and the assessment made by blood pressure post-dialysis indicated a significant association (p=0,029, qui-square test). On the other hand, there was a significant association (p <0.05, chi-square test) among the criteria for treatment adherence and issues investigated in the interview - the perception on the quality of the health services provided to patients, the difficulties following the prescribed diet, the characterization of the days between dialysis sessions and the perception of patients about the dialysis sessions. It was also noted a significant association (p <0.05, Levene test) between adherence to therapy and scales that constitute the MIPS. The health team characterized the patients more adherent behavior as an attitude of acceptance of the treatment, looking actively for their implementation, for more information and knowledge, and establishing a positive communication with the team and with other patients. Similar results were confirmed by the MIPS evaluation. According to that assessment the more compliant patients adopt a more optimistic attitude, trying to act or adapt themselves to their environment, processing cognitively both concrete and objective information, such as more speculative and symbolic information. In addition they establish a gregarious, cooperative, submissive and flexibly pattern of interpersonal relationships to social demands. These characteristics managed to explain 55.7% of the adherence variation according the health team and 23.3% of the variation according the CaxP laboratory indicator. Conclusions: The MIPS shown to be able to identify the most and least adherent to therapy patients. The use of different adherence indicators is important for an evaluation covering the different facets of this process. The adhesion levels are observed within registered by the relevant literature. There is need for further studies with a larger sample to deepen the data findings in this work