991 resultados para Plane Fracture Problem


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From 1950 to 1990 a total of 45,862 strains (31,517 isolates from human sources, and 14,345 of non-human origin) were identified at Instituto Adolfo Lutz. No prevalence of any serovars was seen during the period 1950-66 among human sources isolates. Important changing pattern was seen in 1968, when S. Typhimurim surprisingly increased becoming the prevalent serovar in the following decades. During the period of 1970-76, S. Typhimurium represented 77.7% of all serovars of human origin. Significant rise in S. Agona isolation as well as in the number of different serovars among human sources strains were seen in the late 70' and the 80's. More than one hundred different serovars were identified among non-human origin strains. Among serovars isolated from human sources, 74.9%, 15.5%, and 3.7% were recovered from stool, blood, and cerebrospinal fluid cultures, respectively. The outbreak of meningitis by S. Grumpensis in the 60's, emphasizes the concept that any Salmonella serovars can be a cause of epidemics, mainly of the nosocomial origin. This evaluation covering a long period shows the important role of the Public Health Laboratory in the surveillance of salmonellosis, one of the most frequent zoonosis in the world.

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The minimum interval graph completion problem consists of, given a graph G = ( V, E ), finding a supergraph H = ( V, E ∪ F ) that is an interval graph, while adding the least number of edges |F| . We present an integer programming formulation for solving the minimum interval graph completion problem recurring to a characteri- zation of interval graphs that produces a linear ordering of the maximal cliques of the solution graph.

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In this paper we address an order processing optimization problem known as minimization of open stacks (MOSP). We present an integer pro gramming model, based on the existence of a perfect elimination scheme in interval graphs, which finds an optimal sequence for the costumers orders.

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The current study aimed to compare the shoulder kinematics (3D scapular orientation, scapular angular displacement and scapulohumeral rhythm) of asymptomatic participants under unloaded and loaded conditions during unilateral shoulder elevation in the scapular plane. We used a repeated-measures design with a convenience sample. Eleven male participants with an age range of 21–28 years with no recent history of shoulder injury participated in the study. The participants performed isometric shoulder elevation from a neutral position to approximately 150 degrees of elevation in the scapular plane in intervals of approximately 30 degrees during unloaded and loaded conditions. Shoulder kinematic data were obtained with videogrammetry. During shoulder elevation, the scapula rotated upwardly and externally, and tilted posteriorly. The addition of an external load did not affect 3D scapular orientation, scapular angular displacement, or scapulohumeral rhythm throughout shoulder elevation (P > .05). In clinical practice, clinicians should expect to observe upward and external rotation and posterior tilt of the scapula during their assessments of shoulder elevation. Such behavior was not influenced by an external load normalized to 5% of body weight when performed in an asymptomatic population.

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A intervenção humana no manuseamento de veículos submarinos operados remotamente (ROVs) é um requisito necessário para garantir o sucesso da missão e a integridade do equipamento. Contudo, a sua teleoperação não é fácil, pelo que a condução assistida destes veículos torna-se relevante. Esta dissertação propõe uma solução para este problema para ROVs de 3DOF (surge, heave e yaw). São propostas duas abordagens distintas – numa primeira propõe-se um sistema de controlo Image Based Visual Servoing (IBVS) tendo em vista a utilização exclusiva de uma câmara (sensor existente neste tipo de sistemas) por forma a melhorar significativamente a teleoperação de um pequeno ROV; na segunda, propõe-se um sistema de controlo cinemático para o plano horizontal do veículo e um algoritmo de uma manobra capaz de dotar o ROV de movimento lateral através de uma trajectória dente-de-serra. Demonstrou-se em cenários de operação real que o sistema proposto na primeira abordagem permite ao operador de um ROV com 3DOF executar tarefas de alguma complexidade (estabilização) apenas através de comandos de alto nível, melhorando assim drasticamente a teleoperação e qualidade de inspecção do veículo em questão. Foi também desenvolvido um simulador do ROV em MATLAB para validação e avaliação das manobras, onde o sistema proposto na segunda abordagem foi validado com sucesso.

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RESUMO - Contexto: A osteoporose é uma doença sistémica associada à diminuição da resistência óssea que condiciona o aparecimento de fracturas por traumatismos de baixa energia as quais reduzem em muitos casos a esperança e a qualidade de vida, implicando um elevado número de horas de dedicação dos cuidadores e conduzindo, em muitos casos, à necessidade de institucionalização dos doentes. Em Portugal, ocorrem cerca de 40.000 fracturas anualmente, das quais 8.500 do fémur proximal, que se estima consumirem mais de 50 milhões de euros só em cuidados hospitalares1. Objectivo: Avaliar o impacto económico da institucionalização na Rede Nacional de Cuidados Continuados Integrados e Lares da 3ª idade por fractura de etiologia osteoporótica em mulheres no ano 2009, em Portugal. Métodos: O estudo começa por analisar sucintamente os aspectos clínicos, sociais e epidemiológicos da osteoporose, focando a perda de autonomia e qualidade de vida dos doentes vítimas deste episódio e a subsequente necessidade de institucionalização. Descrevem-se os custos associados à institucionalização na RNCCI, em Portugal, ano 2009, utilizando como fonte principal a base de dados da instituição “Gestcare CCI”, complementada com dados da literatura. Apuram-se os custos totais associados ao encaminhamento dos doentes para Lares de 3ª Idade em Portugal no ano 2009, utilizando-se informação proveniente de um painel de Delphi modificado e dados da literatura. A valorização dos recursos tem por base os preços em vigor no território nacional, expressos nos decretos-lei devidamente referenciados. Resultados: No ano 2009 em Portugal foram empregues cerca de 2,5 milhões de euros no internamento das mulheres na RNCCI, na perspectiva da sociedade, sendo cerca de 2,2 milhões atribuíveis à osteoporose (90%). Cerca de 91% dos custos totais são alocados à fractura osteoporótica da anca (2 milhões €). Para a fractura vertebral, úmero e punho os custos foram mais baixos - 7,1%, 1,3% e 1% dos custos totais da osteoporose, respectivamente. Nos Lares de 3ª idade, estimou-se a admissão de aproximadamente 14.372 doentes com fractura osteoporótica em diferentes localizações, em 2009, Portugal, com um custo que oscilou entre os 19 e os 21,6 milhões de euros. A fractura osteoporótica da anca foi a mais incidente e a que representou custos mais elevados para a Segurança Social – entre 17,5 e 19,7 milhões de euros. Considerando como referência os 52 milhões de euros gastos em 2006 no tratamento hospitalar da fractura da anca (DGS, 2006), o encaminhamento das mulheres para a RNCCI e Lares da 3ª Idade corresponde a 42% do bolo total. Assim, os resultados nacionais enquadram-se no que se encontra descrito na literatura internacional - os custos atribuíveis à hospitalização oscilaram entre 17%50 e 63%29 da despesa total da doença e das institucionalizações entre os 16%58 e os 59%51. Conclusões: Em Portugal o impacto económico da institucionalização por fractura osteoporótica, sobretudo por fractura da anca, não é desprezável e mostra que existiriam poupanças significativas se fosse possível reduzir a prevalência da doença em Portugal. Face às alterações demográficas associadas ao envelhecimento da população, é expectável que a incidência e custos com o tratamento das fracturas do colo do fémur, mais associadas à osteoporose, venham a subir nos próximos anos, pelo que o combate à doença deve ser considerada uma prioridade nacional. A decisão pela opção por determinados programas de prevenção da doença ou da comparticipação ou não de determinada terapêutica necessita contudo de ser complementada com a medição da dimensão dos benefícios terapêuticos. --- ABSTRACT - Background: Osteoporosis is a systemic disease associated with the loss off the bone strength and it is one of the major causes of low energy fractures, which in many cases reduce life hope and quality. This happens because it has associated extensive treatments and it usually carries loss of independence, implying many hours of caregivers dedication and leading, in many cases, to the institutionalization of the patients. In Portugal, about 40,000 fractures occur annually, which 8,500 are proximal femur, and that are estimated to consume over 50 million euros only in hospital care. Objective: Evaluate the economic impact of institutionalization on the Integrated Continued Care National Network (RNCCI) and Care Homes associated to osteoporotic fractures in women, in the year 2009 in Portugal. Methods: The study begins by reviewing briefly the clinical, social, and epidemiological studies of osteoporosis and osteoporotic fractures, focusing on the patient autonomy loss and life quality. The total and average costs per episode associated with the institutionalization in RNCCI are described, in Portugal, year 2009, using as main data source the application "Gestcare CCI", complemented with literature data. The total costs associated with the patients referral for the Care Homes in Portugal in 2009 is also calculated, using information from a modified Delphi panel and some literature data. The resources valuation is based on prices prevailing in Portugal. Results: In 2009, women relocation in RNCCI consumed approximately 2.5 million euros, which 2.2 million are attributable to osteoporosis (90%). About 91% of the total costs are allocated to osteoporotic hip fracture (€ 2 million). For vertebral, humerus, and wrist fracture, the associated costs were lower, 7.1%, 1.3%, and 1% of total costs of osteoporosis treatment, respectively. In Care Homes, an intake of approximately 14 372 patients with osteoporotic fracture was estimated, at a cost that is between 19 and 21.6 million euros. The osteoporotic hip fracture was the most frequent and represented higher costs for Social Security - between 17.5 and 19.7 million euros. Taking as reference the 52 million spent in 2006 with hospital treatment of hip fracture (DGS, 2006), referring women to RNCCI and Care Homes represents 42% of the total costs. The results are in accordance with the international literature - costs attributable to hospitalization ranged between 17% and 63% of total expenditure of illness and institutionalization between 16% and 59%. Conclusions: In Portugal, the economic impact of institutionalization for osteoporotic fracture, particularly for hip fracture, is not negligible. It was shown that there would be significant savings if it were possible to reduce the prevalence of the disease in Portugal. Femoral fractures were the second most frequent diagnosis in RNCCI in 2008 and 2009 (16% of all episodes recorded). The execution of RNCCI in 2008 was 75 million euros, and 2.7% consumed by hip fracture and 0.3% by wrist, humerus, and spine fractures. The average cost per episode in 2009, from the perspective of society, for hip fracture, vertebral, humerus, and wrist (or non-osteoporotic) was € 5,195, € 5,160, € 5,030, and € 4,854 respectively. Thus, considering an average cost per episode in RNCCI from January to March of 3230€, the expense related to the treatment of these patients in RNCCI in 2009 was higher. For the Care Homes, an intake of approximately 14 372 patients with osteoporotic fracture in 2009 was estimated, at a cost to Social Security that ranged from 19 to 21.6 million €. The osteoporotic hip fracture was the most frequent and it was shown to absorve higher resources from Social Security - between 17.5 and 19.7 million €. This was followed by the analysis of vertebral and humerus fracture and the results showed that these fractures have a low incidence and low proportion of institutionalization, with a significantly lower cost - only about 4.7% and 3.3% of total expenditure, respectively. With demographic changes associated to ageing, it is expected that the incidence and treatment cost of the femoral neck fractures, more commonly associated with osteoporosis, will climb in coming years, so the fight against the disease should be considered a national priority. The decision to choose a certain disease prevention program or to reimburse a certain drug not should only account about the costs, but also the benefits of it. In fact, the size and impact of this problem, makes it necessary to focus all interventions in the prevention of these episodes either by using an appropriate therapy, either through real programs for disease prevention. Once the problem is installed, we must measure the health gains associated with the patient institutionalization by conducting additional research.

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This paper applies Pseudo Phase Plane (PPP) and Fractional Calculus (FC) mathematical tools for modeling world economies. A challenging global rivalry among the largest international economies began in the early 1970s, when the post-war prosperity declined. It went on, up to now. If some worrying threatens may exist actually in terms of possible ambitious military aggression, invasion, or hegemony, countries’ PPP relative positions can tell something on the current global peaceful equilibrium. A global political downturn of the USA on global hegemony in favor of Asian partners is possible, but can still be not accomplished in the next decades. If the 1973 oil chock has represented the beginning of a long-run recession, the PPP analysis of the last four decades (1972–2012) does not conclude for other partners’ global dominance (Russian, Brazil, Japan, and Germany) in reaching high degrees of similarity with the most developed world countries. The synergies of the proposed mathematical tools lead to a better understanding of the dynamics underlying world economies and point towards the estimation of future states based on the memory of each time series.

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Proceedings of the 10th Conference on Dynamical Systems Theory and Applications

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The use of adhesive joints has increased in recent decades due to its competitive features compared with traditional methods. This work aims to estimate the tensile critical strain energy release rate (GIC) of adhesive joints by the Double-Cantilever Beam (DCB) test. The J-integral is used since it enables obtaining the tensile Cohesive Zone Model (CZM) law. An optical measuring method was developed for assessing the crack tip opening (δn) and adherends rotation (θo). The proposed CZM laws were best approximated by a triangular shape for the brittle adhesive and a trapezoidal shape for the two ductile adhesives.

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The Container Loading Problem (CLP) literature has traditionally evaluated the dynamic stability of cargo by applying two metrics to box arrangements: the mean number of boxes supporting the items excluding those placed directly on the floor (M1) and the percentage of boxes with insufficient lateral support (M2). However, these metrics, that aim to be proxies for cargo stability during transportation, fail to translate real-world cargo conditions of dynamic stability. In this paper two new performance indicators are proposed to evaluate the dynamic stability of cargo arrangements: the number of fallen boxes (NFB) and the number of boxes within the Damage Boundary Curve fragility test (NB_DBC). Using 1500 solutions for well-known problem instances found in the literature, these new performance indicators are evaluated using a physics simulation tool (StableCargo), replacing the real-world transportation by a truck with a simulation of the dynamic behaviour of container loading arrangements. Two new dynamic stability metrics that can be integrated within any container loading algorithm are also proposed. The metrics are analytical models of the proposed stability performance indicators, computed by multiple linear regression. Pearson’s r correlation coefficient was used as an evaluation parameter for the performance of the models. The extensive computational results show that the proposed metrics are better proxies for dynamic stability in the CLP than the previous widely used metrics.

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The Rural Postman Problem (RPP) is a particular Arc Routing Problem (ARP) which consists of determining a minimum cost circuit on a graph so that a given subset of required edges is traversed. The RPP is an NP-hard problem with significant real-life applications. This paper introduces an original approach based on Memetic Algorithms - the MARP algorithm - to solve the RPP and, also deals with an interesting Industrial Application, which focuses on the path optimization for component cutting operations. Memetic Algorithms are a class of Metaheuristics which may be seen as a population strategy that involves cooperation and competition processes between population elements and integrates “social knowledge”, using a local search procedure. The MARP algorithm is tested with different groups of instances and the results are compared with those gathered from other publications. MARP is also used in the context of various real-life applications.

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Although the issue of the out-of-plane response of unreinforced masonry structures under earthquake excitation is well known with consensus among the research community, this issue is simultaneously one of the more complex and most neglected areas on the seismic assessment of existing buildings. Nonetheless, its characterization should be found on the solid knowledge of the phenomenon and on the complete understanding of methodologies currently used to describe it. Based on this assumption, this article presents a general framework on the issue of the out-of-plane performance of unreinforced masonry structures, beginning with a brief introduction to the topic, followed by a compact state of art in which the principal methodologies proposed to assess the out-of-plane behavior of unreinforced masonry structures are presented. Different analytical approaches are presented, namely force and displacement-based, complemented with the presentation of existing numerical tools for the purpose presented above. Moreover, the most relevant experimental campaigns carried out in order to reproduce the phenomenon are reviewed and briefly discussed.

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During the last years, several studies have been made aiming to assess the out-of-plane seismic response of unreinforced stone masonry structures. This fact led to the development of a wide variety of models and approaches, ranging from simple kinematic based analytical models up to complex numerical simulations. Nevertheless, for the sake of simplicity, the out-of-plane seismic response of a masonry wall pier may be obtained by means of a simple single-degree-of-freedom system while still providing good results. In fact, despite the assumptions associated with such a simple formulation, it is also true that the epistemic uncertainty inherent with the selection of appropriate input parameters in more complex models may render them truly ineffective. In this framework, this paper focuses on the study of the out-of-plane bending of unreinforced stone masonry walls (cantilevers) by proposing a simplified analytical approach based on the construction of a linearized four-branch model, which is used to characterize the linear and nonlinear response of such structural elements through an overturning moment-rotation relationship. The formulation of the four-branch model is presented and described in detail and the meaningful parameters used for its construction are obtained from a set of experimental laboratory tests performed on six full-scale unreinforced regular sacco stone masonry specimens. Moreover, a parametric analysis aiming to evaluate the effect of these parameters’ variation on the final configuration of the model is presented and critically discussed. Finally, the results obtained from the application of the developed four-branch model on real unreinforced regular sacco stone masonry walls are thoroughly analysed and the main conclusions obtained from its application are summarized.

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Stone masonry is one of the oldest and most worldwide used building techniques. Nevertheless, the structural response of masonry structures is complex and the effective knowledge about their mechanical behaviour is still limited. This fact is particularly notorious when dealing with the description of their out-of-plane behaviour under horizontal loadings, as is the case of the earthquake action. In this context, this paper describes an experimental program, conducted in laboratory environment, aiming at characterizing the out-of-plane behaviour of traditional unreinforced stone masonry walls. In the scope of this campaign, six full-scale sacco stone masonry specimens were fully characterised regarding their most important mechanic, geometric and dynamic features and were tested resorting to two different loading techniques under three distinct vertical pre-compression states; three of the specimens were subjected to an out-of-plane surface load by means of a system of airbags and the remaining were subjected to an out-of-plane horizontal line-load at the top. From the experiments it was possible to observe that both test setups were able to globally mobilize the out-of-plane response of the walls, which presented substantial displacement capacity, with ratios of ultimate displacement to the wall thickness ranging between 26 and 45 %, as well as good energy dissipation capacity. Finally, very interesting results were also obtained from a simple analytical model used herein to compute a set of experimental-based ratios, namely between the maximum stability displacement and the wall thickness for which a mean value of about 60 % was found.