62 resultados para propositional linear-time temporal logic


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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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Fresh basil (Ocimum basilicum L.) is used in food, phytotherapic industry, and in traditional therapeutic, due to its essential oil content and composition. Nevertheless basil can not be kept for long periods after harvest and its quality can be reduced. This work aimed to assess the influence of the season and harvest time in the postharvest conservation of basil stored for different periods. Basil was harvested at 8 am and 4 pm both in August/1999 and January/2000. Cuttings were conditioned in PVC packages and stored for 3, 6, and 9 days. During storage, chlorophyll content, essential oil content and composition were determined as well as microbiological analyses were carried out. Harvest season and the days of storage influenced the final content of essential oil. There was a linear decrease in the content of essential oil, in the chlorophyll content and in the number of mold and yeast colonies during storage. There was no effect of cropping season or harvest hour on essential oil composition, but the eugenol and linalool content increased during storage. Coliforms were under 0.3 MPN g-1 and the number of Staphylococcus aureus was under 1.0x10² UFC g-1.

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O objetivo deste trabalho foi avaliar a oscilação dos níveis freáticos em uma bacia hidrográfica, no período seco, e modelar a variabilidade espaço-temporal desses níveis por meio de técnicas geoestatísticas multivariadas. A área de estudo foi o alto da Bacia do Rio Jardim, Distrito Federal. O regime hídrico dessa região é marcado pela sazonalidade, com períodos chuvosos (outubro a abril) e secos (maio a setembro) distintos, que determinam o comportamento dos níveis freáticos. Quanto aos fenômenos com indexação espaço-temporal, a geoestatística propõe soluções pelo modelo linear de co-regionalização, permitindo a quantificação e mapeamento das reservas hídricas subterrâneas. Quantificaram-se o volume perdido de água e o risco associado às estimativas pelas medidas de incerteza, criando-se cenários críticos do volume do aqüífero explorado na seca. Na seca, observou-se decréscimo de água nesse aqüífero. O mapa do quantil 10% indicou áreas favoráveis ao uso da água, em que os níveis freáticos oscilaram menos. O mapa do quantil 90% indicou áreas com grandes oscilações dos níveis freáticos que contribuem mais para drenagem e recarga do aqüífero.

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The objective of this study was to adapt a nonlinear model (Wang and Engel - WE) for simulating the phenology of maize (Zea mays L.), and to evaluate this model and a linear one (thermal time), in order to predict developmental stages of a field-grown maize variety. A field experiment, during 2005/2006 and 2006/2007 was conducted in Santa Maria, RS, Brazil, in two growing seasons, with seven sowing dates each. Dates of emergence, silking, and physiological maturity of the maize variety BRS Missões were recorded in six replications in each sowing date. Data collected in 2005/2006 growing season were used to estimate the coefficients of the two models, and data collected in the 2006/2007 growing season were used as independent data set for model evaluations. The nonlinear WE model accurately predicted the date of silking and physiological maturity, and had a lower root mean square error (RMSE) than the linear (thermal time) model. The overall RMSE for silking and physiological maturity was 2.7 and 4.8 days with WE model, and 5.6 and 8.3 days with thermal time model, respectively.

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The objective of this work was to investigate the relationship between changes in the plant community and changes in soil physical properties and water availability, during a succession from alfalfa (Medicago sativa L.) to natural vegetation on the Loess Plateau, China. Data from a succession sere spanning 32 years were collated, and vegetative indexes were compared to changes related to soil bulk density and soil water storage. The alfalfa yield increased for approximately 7 years, then it declined and the alfalfa was replaced by a natural community dominated by Stipa bungeana that began to thrive about 10 years after alfalfa seeding. Soil bulk density increased over time, but the deterioration of the alfalfa was mainly ascribed to a severe reduction in soil water storage, which was lowest around the time when degradation commenced. The results indicated that water consumption by alfalfa could be reduced by reducing plant density. The analysis of the data also suggested that soil water recharge could be facilitated by rotating the alfalfa with other crops, natural vegetation, or bare soil.

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O objetivo deste trabalho foi determinar a melhor alternativa, entre os métodos de agrupamento hierárquico (Ward) e de otimização (Tocher), para a formação de grupos homogêneos de séries de expressão gênica, e realizar previsões quanto à expressão gênica dessas séries, a partir de pequeno número de observações temporais. Os dados utilizados referem-se à expressão de genes que atuam sobre o ciclo celular de Saccharomyces cerevisiae e corresponderam a 114 séries de expressão gênica, cada uma com dez valores de "fold-change" (medida da expressão gênica) ao longo do tempo (0, 15, 30, 45, 60, 75, 90, 105, 120 e 135 min). As estimativas dos parâmetros dos modelos autorregressivos AR(p) foram previamente ajustadas a séries individuais (de cada gene) de dados "microarray time series" e utilizadas, como variáveis, no processo de agrupamento. As previsões da expressão gênica foram feitas dentro de cada grupo formado, a partir dos ajustes no modelo AR(p) para dados em painel. O método de Ward foi o mais apropriado para a formação de grupos de genes com séries homogêneas. Uma vez obtidos esses grupos, é possível ajustar o modelo AR(2) para dados em painel e predizer a expressão gênica em um tempo futuro (135 min), a partir de um pequeno número de observações temporais (os outros nove valores de "fold-change").

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The objective of this work was to evaluate the seasonal variation of soil cover and rainfall erosivity, and their influences on the revised universal soil loss equation (Rusle), in order to estimate watershed soil losses in a temporal scale. Twenty-two TM Landsat 5 images from 1986 to 2009 were used to estimate soil use and management factor (C factor). A corresponding rainfall erosivity factor (R factor) was considered for each image, and the other factors were obtained using the standard Rusle method. Estimated soil losses were grouped into classes and ranged from 0.13 Mg ha-1 on May 24, 2009 (dry season) to 62.0 Mg ha-1 on March 11, 2007 (rainy season). In these dates, maximum losses in the watershed were 2.2 and 781.5 Mg ha-1 , respectively. Mean annual soil loss in the watershed was 109.5 Mg ha-1 , but the central area, with a loss of nearly 300.0 Mg ha-1 , was characterized as a site of high water-erosion risk. The use of C factor obtained from remote sensing data, associated to corresponding R factor, was fundamental to evaluate the soil erosion estimated by the Rusle in different seasons, unlike of other studies which keep these factors constant throughout time.

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A new procedure to find the limiting range of the photomultiplier linear response of a low-cost, digital oscilloscope-based time-resolved laser-induced luminescence spectrometer (TRLS), is presented. A systematic investigation on the instrument response function with different signal input terminations, and the relationship between the luminescence intensity reaching the photomultiplier and the measured decay time are described. These investigations establish that setting the maximum intensity of the luminescence signal below 0.3V guarantees, for signal input terminations equal or higher than 99.7 ohm, a linear photomultiplier response.

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In this manuscript, seasonal and spatial trends of water collected from two sampling places in the Preto River in the Turvo-Grande watershed were evaluated. Water samples were collected during June/07 to July/08 and parameters sulphate, total organic carbon, ammonia, conductivity, dissolved oxygen, temperature, dissolved total solids and nitrate were quantified. Seasonal trend indicated sanitary effluents as a point source of contamination in both sampling points. Vertical trends demonstrated that the Municipal Dam was not stratified and received a diffuse source of pollutants from flooding and agriculture runoffs. It was also verified that there is relatively fast ammonia consumption kinetics having a half-life time of 1.43 h which can explain the low ammonia concentrations found in these aquatic bodies.

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A sarna da macieira, causada por Venturia inaequalis, é uma das principais doenças da cultura. Devido à grande preocupação com os riscos de contaminação ambiental e intoxicação humana, o cultivo orgânico surge como uma alternativa, buscando preservar a qualidade do produto final em relação ao sistema convencional. Com o objetivo de avaliar a epidemiologia da sarna da macieira nos sistemas convencional e orgânico de produção, foi empregada a técnica de análise da dinâmica temporal, nas cultivares Royal Gala e Fuji, nas condições edafo-climáticas do Sul do Brasil. A incidência foi quantificada semanalmente, gerando 16 mapas em cada sistema de produção e quinzenalmente, a severidade da doença foi avaliada em 100 folhas, distribuídas em quatro ramos, de acordo com escala diagramática específica, com 12 repetições. Foram plotadas curvas de progresso da doença e as epidemias comparadas em relação a) início do aparecimento dos sintomas (IAS); b) tempo para atingir a máxima intensidade da doença (TAMID); c) valor máximo de severidade da doença (y max) e d) área abaixo da curva de progresso da doença (AACPD). Os dados de incidência foram analisados por meio de análise de regressão linear simples, ajustados para três modelos empíricos, Logístico, Monomolecular e Gompertz. As cultivares avaliadas foram suscetíveis à V. inaequalis, com diferenças significativas entre as cultivares e entre os sistemas de produção. Houve maiores níveis de intensidade de doença e taxa de progresso da doença (r) no sistema orgânico que no sistema convencional de produção, sendo que o modelo mais apropriado para descrever a curva de progresso da doença foi o Logístico.

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ABSTRACT 'The Duologue of King/Governor Pāyāsi' ("Long Discourses") has long been recognised as a source for the proto-materialism current at the time of the Buddha. What needs to be stressed is the significance of the text as a pointer to the development of Logic in India. Perception (observation and experiment employing the joint method of agreement and difference), which is an accepted method of experimental enquiry, and reasoning from analogy, which can lead at best to a probable conclusion - these two are the only means employed to settle the dispute concerning the existence of the other-world. The Jain version of the same duologue-cum-parable, though varying in minor details regarding the name and identity of the monk refuting the king/governor, contains the same contrast, namely, perception versus analogical reasoning. There can be little doubt that the original parable was conceived with a view to asserting the existence of the other-world. In the Kaṭha Upaniṣad (sixth century BCE), an earlier Brahmanical text, however, instead of argument by analogy, verbal testimony (śabda) was invoked to settle the same point. Naciketas is assailed by doubt about the existence of a person after his or her death. The authority of Yama, the Pluto of Indian mythology, is invoked to convince him that the other-world does exist. Thus, the three parables taken together exhibit three means of knowledge in operation: verbal testimony and argument by analogy pitted against perception.

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O objetivo desse trabalho foi caracterizar os padrões temporal e espacial do Tomato yellow vein streak virus (ToYVSV) em tomatais cultivados em condições de campo, no município de Sumaré, e de estufa plástica, na região de Elias Fausto, Estado de São Paulo. No ensaio de campo, plantado com a variedade Alambra, foram avaliadas 4.032 plantas, distribuídas em oito blocos. Em oito estufas plásticas, com plantios escalonados da variedade Ikram, foram avaliadas 6.016 plantas. As avaliações foram feitas com base nos sintomas característicos induzidos por esse vírus. A confirmação da identidade do vírus foi feita por meio da análise da seqüência de nucleotídeos de parte do DNA-A viral (genes AV1 e AC3). No ensaio em condições de campo, a incidência da doença evoluiu lentamente, desde um mínimo de 0,002 (proporção de plantas sintomáticas) até um máximo de 0,0497. Mesmo assim, foi possível constatar um efeito de borda, pois a incidência média de plantas doentes nos blocos situados nos bordos da área foi 2,1 vezes maior do que naqueles internos. O progresso da incidência da doença foi linear, o que indica que novas infecções foram devidas principalmente a um influxo constante de vetores virulíferos de fora para dentro da área avaliada. Nos plantios em estufas plásticas, os níveis finais de doença foram fortemente dependentes da época de plantio, com médias variando de 4,8% a 69,3%. A distribuição espacial de plantas sintomáticas nesses plantios foi fortemente agregada. Essa agregação provavelmente não se deve a infecções secundárias dentro das estufas plásticas, mas sim à concentração de plantas sintomáticas nos bordos das estufas, conseqüência da migração de vetores virulíferos a partir de áreas externas à estufa. Com base nesses resultados, sugere-se a eliminação de fontes de inóculo representadas por plantios mais velhos de tomateiro e por hospedeiras do vírus na vegetação espontânea como uma das principais medidas para o manejo da doença.

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Contemporary logic is confined to a few paradigmatic attitudes such as belief, knowledge, desire and intention. My purpose is to present a general model-theoretical semantics of propositional attitudes of any cognitive or volitive mode. In my view, one can recursively define the set of all psychological modes of attitudes. As Descartes anticipated, the two primitive modes are those of belief and desire. Complex modes are obtained by adding to primitive modes special cognitive and volitive ways or special propositional content or preparatory conditions. According to standard logic of attitudes (Hintikka), human agents are either perfectly rational or totally irrational. I will proceed to a finer analysis of propositional attitudes that accounts for our imperfect but minimal rationality. For that purpose I will use a non standard predicative logic according to which propositions with the same truth conditions can have different cognitive values and I will explicate subjective in addition to objective possibilities. Next I will enumerate valid laws of my general logic of propositional attitudes. At the end I will state principles according to which minimally rational agents dynamically revise attitudes of any mode.

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The present article shows that there are consistent and decidable many- valued systems of propositional logic which satisfy two or all the three criteria for non- trivial inconsistent theories by da Costa (1974). The weaker one of these paraconsistent system is also able to avoid a series of paradoxes which come up when classical logic is applied to empirical sciences. These paraconsistent systems are based on a 6- valued system of propositional logic for avoiding difficulties in several domains of empirical science (Weingartner (2009)).

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In this article I deal with time as a notion of epistemological content associated though with the notion of a subjective consciousness co-constitutive of physical reality. In this phenomenologically grounded approach I attempt to establish a 'metaphysical' aspect of time, within a strictly epistemological context, in the sense of an underlying absolute subjectivity which is non-objectifiable within objective temporality and thus non-susceptible of any ontological designation. My arguments stem, on the one hand, from a version of quantum-mechanical theory (History Projection Operator theory, HPO theory) in view of its formal treatment of two different aspects of time within a quantum context. The discrete, partial-ordering properties (the notions of before and after) and the dynamical-parameter properties reflected in the wave equations of motion. On the other hand, to strengthen my arguments for a transcendental factor of temporality, I attempt an interpretation of some relevant conclusions in the work of J. Eccles ([5]) and of certain results of experimental research of S. Deahaene et al. ([2]) and others.