84 resultados para fuzzy shape evolution
em Scielo Saúde Pública - SP
Resumo:
Modeling of water movement in non-saturated soil usually requires a large number of parameters and variables, such as initial soil water content, saturated water content and saturated hydraulic conductivity, which can be assessed relatively easily. Dimensional flow of water in the soil is usually modeled by a nonlinear partial differential equation, known as the Richards equation. Since this equation cannot be solved analytically in certain cases, one way to approach its solution is by numerical algorithms. The success of numerical models in describing the dynamics of water in the soil is closely related to the accuracy with which the water-physical parameters are determined. That has been a big challenge in the use of numerical models because these parameters are generally difficult to determine since they present great spatial variability in the soil. Therefore, it is necessary to develop and use methods that properly incorporate the uncertainties inherent to water displacement in soils. In this paper, a model based on fuzzy logic is used as an alternative to describe water flow in the vadose zone. This fuzzy model was developed to simulate the displacement of water in a non-vegetated crop soil during the period called the emergency phase. The principle of this model consists of a Mamdani fuzzy rule-based system in which the rules are based on the moisture content of adjacent soil layers. The performances of the results modeled by the fuzzy system were evaluated by the evolution of moisture profiles over time as compared to those obtained in the field. The results obtained through use of the fuzzy model provided satisfactory reproduction of soil moisture profiles.
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This study was carried out to study the physical properties of the jatropha beans over the drying under six air conditions, based on measurements of roundness, sphericity, volume, superficial area, projected area and surface/volume ratio. Jatropha beans with moisture content around 0.61 (decimal d.b.) were subjected to thin-layer drying in oven with forced-air circulation under six temperature conditions (36, 45, 60, 75, 90 and 105 °C) and relative humidity of 31.7; 19.6; 9.4; 4.8; 2.6 and 1.5% respectively, until reaching the moisture content of 0.11 ± 0.006 (decimal d. b.). The results showed that the necessary time for jatropha beans to reach the moisture content of 0.11 ± 0.006 (decimal d.b.) were 1.5; 2.25; 3.0; 4.75; 6.75 and 12.0 h for the drying temperatures of 105, 90, 75, 60, 45 and 36 °C, respectively; and the reduction in the moisture content as well as the drying conditions promoted changes in the shape and reduced the size of the jatropha beans.
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This article reviews the origins and evolution of global banking and addresses the emerging patterns for the year 2000 and beyond.
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Neste artigo, são apresentados testes empíricos para a investigação de ocorrência de fenômenos de sobre-reação e sub-reação no mercado de ações brasileiro. Para esses testes, é proposto um modelo baseado na teoria de conjuntos Fuzzy, que possui forte relação com as heurísticas de representatividade e ancoramento, estabelecidas na teoria de finanças comportamentais. O modelo proposto é empregado para a formação de carteiras e utiliza indicadores financeiros de companhias abertas. Para as análises são utilizados dois conjuntos de ações, um do setor de petróleo e petroquímica e outro do setor têxtil, com indicadores financeiros relativos ao período de 1994 a 2005.
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Este trabalho desenvolve um novo modelo Fuzzy-DEA-Game (FDG) para apoiar o estabelecimento de estratégias de produção. Esse modelo combina a Análise Envoltória de Dados (DEA) com conceitos da Teoria dos Conjuntos Fuzzy e do Jogo da Barganha de Nash. O modelo permite uma avaliação da eficiência produtiva e econômica dos produtos, o que pode resultar num portfólio de produtos mais rentáveis e de interesse do mercado consumidor. O modelo foi aplicado em uma empresa do segmento de energia. Os resultados obtidos com a aplicação do modelo FDG mostraram-se aderentes à realidade da empresa estudada e forneceram metas para a redução dos níveis de recursos (entradas) necessários para a fabricação dos produtos e para aumento dos níveis de resultados (saídas) oriundos da comercialização desses produtos. Como resultado adicional importante, o modelo FDG permitiu a identificação dos produtos do portfólio que são mais sensíveis à ocorrência de incerteza.
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Brazil has become the center of the spotlight of the whole world recently, amongst many other reasons, one of them was because it was chosen to host a series of mega sporting events - Pan American Games in 2007, Confederations Football Cup in 2013, Fifa Football World Cup 2014 Games and 2016 Olympic and Paralympic Games in 2016. However, little is known about the country's administrative governmental structure focused on sport policy. The available studies focus their analysis on the sport policies content, but not on the arrangement of its structural decision-making. The main aim of this article is indeed to describe, based on official documentation, the evolution and the current arrangements of the government responsible for the administrative structure for the planning and implementation of sports policies in Brazil. Thus, we tried to list the main problems arising from the organization of the Brazilian sports' management. These problems are: (1) inappropriate institutional structure in terms of human resources and obstacles to participation by other social actors beyond the officials (parliament and members of the Ministry of Sports) in the sports policy; (2) disarticulation between public institutions generating redundancies and conflicts of jurisdiction due to the poor division of labor between bureaucracy agencies; and (3) inadequate planning proved by the lack of organization of some institutions, and by the lack of assessment and continuity of public policies over time. Therefore, we must emphasize those problems from above, and due to these administrative arrangements, Brazilian sports' policy has big challenges in the sport development in this country, which includes the creation of a national "system" for sports and a priority investment in sport education.
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INTRODUCTION: The evolution of virulence in host-parasite relationships has been the subject of several publications. In the case of HIV virulence, some authors suggest that the evolution of HIV virulence correlates with the rate of acquisition of new sexual partners. In contrast some other authors argue that the level of HIV virulence is independent of the sexual activity of the host population. METHODS: Provide a mathematical model for the study of the potential influence of human sexual behaviour on the evolution of virulence of HIV is provided. RESULTS: The results indicated that, when the probability of acquisition of infection is a function both of the sexual activity and of the virulence level of HIV strains, the evolution of HIV virulence correlates positively with the rate of acquisition of new sexual partners. CONCLUSION: It is concluded that in the case of a host population with a low (high) rate of exchange of sexual partners the evolution of HIV virulence is such that the less (more) virulent strain prevails.
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OBJECTIVE: To introduce a fuzzy linguistic model for evaluating the risk of neonatal death. METHODS: The study is based on the fuzziness of the variables newborn birth weight and gestational age at delivery. The inference used was Mamdani's method. Neonatologists were interviewed to estimate the risk of neonatal death under certain conditions and to allow comparing their opinions and the model values. RESULTS: The results were compared with experts' opinions and the Fuzzy model was able to capture the expert knowledge with a strong correlation (r=0.96). CONCLUSIONS: The linguistic model was able to estimate the risk of neonatal death when compared to experts' performance.
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OBJETIVO: Desenvolver e comparar dois modelos matemáticos, um deles baseado em regressão logística e o outro em teoria de conjuntos fuzzy, para definir a indicação para a realização do exame cintilográfico a partir de resultados dos exames laboratoriais. MÉTODOS: Foram identificados 194 pacientes que tiveram cálcio e paratormônio séricos medidos a partir da base de registros de cintilografia de paratiróides realizadas em laboratório de diagnóstico de São Paulo, no período de janeiro de 2000 a dezembro de 2004. O modelo de regressão logística foi desenvolvido utilizando-se o software SPSS e o modelo fuzzy, o Matlab. A performance dos modelos foi comparada utilizando-se curvas ROC. RESULTADOS: Os modelos apresentaram diferenças estatisticamente significantes (p=0,026) nos seus desempenhos. A área sob a curva ROC do modelo de regressão logística foi de 0,862 (IC 95%: 0,811-0,913) e do modelo de lógica fuzzy foi 0,887 (IC 95%: 0,840-0,933). Este último destacou-se como particularmente útil porque, ao contrário do modelo logístico, mostrou capacidade de utilizar informações de paratormônio em intervalo em que os valores de cálcio mostraram-se pouco discriminantes. CONCLUSÕES: O modelo matemático baseado em teoria de conjuntos fuzzy pareceu ser mais adequado do que o baseado em regressão logística como método para decisão da realização de cintilografia das paratiróides. Todavia, sendo resultado de um exercício metodológico, inferências sobre o comportamento do objeto podem ser impróprias, dada a não representatividade populacional dos dados.
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OBJECTIVE To analyze the temporal evolution of maternal mortality and its spatial distribution.METHODS Ecological study with a sample made up of 845 maternal deaths in women between 10 and 49 years, registered from 1999 to 2008 in the state of Rio Grande do Sul, Southern Brazil. Data were obtained from Information System on Mortality of Ministry of Health. The maternal mortality ratio and the specific maternal mortality ratio were calculated from records, and analyzed by the Poisson regression model. In the spatial distribution, three maps of the state were built with the rates in the geographical macro-regions, in 1999, 2003, and 2008.RESULTS There was an increase of 2.0% in the period of ten years (95%CI 1.00;1.04; p = 0.01), with no significant change in the magnitude of the maternal mortality ratio. The Serra macro-region presented the highest maternal mortality ratio (1.15, 95%CI 1.08;1.21; p < 0.001). Most deaths in Rio Grande do Sul were of white women over 40 years, with a lower level of education. The time of delivery/abortion and postpartum are times of increased maternal risk, with a greater negative impact of direct causes such as hypertension and bleeding.CONCLUSIONS The lack of improvement in maternal mortality ratio indicates that public policies had no impact on women’s reproductive and maternal health. It is needed to qualify the attention to women’s health, especially in the prenatal period, seeking to identify and prevent risk factors, as a strategy of reducing maternal death.
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Two cross-sectional studies on schistosomiasis mansoni were done in Comercinho, Minas Gerais (Brazil), at an interval of 7 years. In 1974 and 1981 feces examinations (KATO-KATZ method) were done in 89 and 90% of the population (about 1,500 inhabitants) and clinical examinations were done in 78 and 92% of the patients who excreted Schistosoma mansoni eggs in the feces, respectively. The rate of infection by S. mansoni did not change (69.9% in 1974 and 70.4% in 1981), but the geometrical mean of eggs per gram of feces (431 ± 4 and 334 ± 4, respectively) and the rate of splenomegaly (11 and 7%, respectively) decreased significantly in 1981, when compared to 1974. This reduction was observed only in the central zones of the town (zones 1-2) where the rate of dwellings with piped water increased from 17 to 44%. In the surroundings (zones 3-4), where the proportion of houses with piped water did not change significantly between 1974 (10%) and 1981 (7%), the geometrical mean of S. mansoni eggs and the rate of splenomegaly did not change either.
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We have evaluated the sensitivity of the classical blood subinoculation method, modified through cyclophosphamide treatment of transferred mice, for the detection of occult parasitaemias in Trypanosoma cruzi chronically infected mice. Besides its simplicity, the method was shown to be highly sensitive for both the "chronic" phase parasites (99% of chronic cases were shown to harbour occult parasitaemias) and for the acute phase parasites (T. cruzi could be detected in 53.8% of animals transferred with one Y strain parasite and in 20% of animals transferred with one CL strain parasite). Using acute phase bloodforms, the assay proved to be more sensitive than conventional subinoculation when dealing with the CL, but not the Y strain of the parasite. With the help of this parasite detection tool, we have studied during a one year period, the evolution of subpatent parasitaemias in a group of mice which survived through chemotherapy from lethal acute phase of T. cruzi infection. Cyclophosphamide transfer assay revealed occult parasitaemias in 100% of the chronic animals, nevertheless, continuous and discontinuous patterns of positivity were observed.
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The recognition profile of the tissue cysts antigens by IgG antibodies was studied during acute and chronic human toxoplasmic infection. Thus the IgG response against Toxoplasma gondii was investigated by immunoblotting in two patients accidentally infected with the RH strain as well as in group of naturally infected patients at acute and chronic phase. There was an overall coincidence of molecular mass among antigens of tachyzoites and tissue cysts recognized by these sera, however, they appear not to be the same molecules. The response against tissue cysts starts early during acute infection, and the reactivity of antibodies is strong against a wide range of antigens. Six bands (between 82 and 151 kDa) were exclusively recognized by chronic phase sera but only the 132 kDa band was positive in more than 50% of the sera analysed. A mixture of these antigens could be used to discriminate between the two infection phases. The most important antigens recognized by the acute and the chronic phase sera were 4 clusters in the ranges 20-24 kDa, 34-39 kDa, 58-80 kDa and 105-130 kDa as well as two additional antigens of 18 and 29 kDa. Both accidentally infected patients and some of the naturally infected patients showed a weak specific response against tissue cyst antigens.
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A total of 24 patients with syphilis and HIV infection were treated from January 1997 to March 2003 at the Infectious Dermatology Outpatient Clinic of the Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil. The caseload consisted of 20 males (83.3%) and four females (16.7%), with a mean age of 38.04 years and mean T CD4+ count of 389.5 cells/mL. Syphilis was diagnosed as secondary in 16 (62.5%) patients, late latent in eight (33.3%), and tertiary in one (4.2%). Manifestations of secondary syphilis were palmar and plantar erythematopapulous cutaneous lesions in nine (37.5%), papulous exanthema in four (16.7%), patchy alopecia in 3 (12.5%) and osteochondritis in one patient (4.2%). Tertiary syphilis was characterized by verrucous lesions. Neurosyphilis was diagnosed in four patients (16.7%), with headache as the only manifestation in two patients. Drugs used in treatment included benzathine penicillin, ceftriaxone, erythromycin, and crystalline penicillin. Cure was achieved in 18 patients (75%). Five patients (20.8%) were retreated, three of whom presented a history of re-exposure. This study confirms the importance of establishing the diagnosis of neurosyphilis in patients with HIV infection, in addition to performing follow-up on treatment for syphilis.
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A case of acute abdomen disease caused by abdominal angiostrongyliasis is reported. A 42-year-old otherwise healthy patient presented with a complaint of nine days of abdominal pain, constipation, disury, fever and right iliac fossa palpable mass. Exploratory laparotomy was performed. After surgical treatment the patient presented serious complications.