2,091 research outputs found
Fourier analysis of stationary time series in function space
We develop the basic building blocks of a frequency domain framework for
drawing statistical inferences on the second-order structure of a stationary
sequence of functional data. The key element in such a context is the spectral
density operator, which generalises the notion of a spectral density matrix to
the functional setting, and characterises the second-order dynamics of the
process. Our main tool is the functional Discrete Fourier Transform (fDFT). We
derive an asymptotic Gaussian representation of the fDFT, thus allowing the
transformation of the original collection of dependent random functions into a
collection of approximately independent complex-valued Gaussian random
functions. Our results are then employed in order to construct estimators of
the spectral density operator based on smoothed versions of the periodogram
kernel, the functional generalisation of the periodogram matrix. The
consistency and asymptotic law of these estimators are studied in detail. As
immediate consequences, we obtain central limit theorems for the mean and the
long-run covariance operator of a stationary functional time series. Our
results do not depend on structural modelling assumptions, but only functional
versions of classical cumulant mixing conditions, and are shown to be stable
under discrete observation of the individual curves.Comment: Published in at http://dx.doi.org/10.1214/13-AOS1086 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Particle Swarm Optimization in Solving Capacitated Vehicle Routing Problem
The Capacitated Vehicle Routing Problem (CVRP) is an NP-Hard problem, which means it is impossible to find a polynomial time solution for it. So researchers try to reach a near optimum solution by using meta-heuristic algorithms. The aim of CVRP is to find optimum route for every vehicle and a sequence of customers, that vehicle serve. This paper proposes a method on how PSO is adjusted for a discrete space problem like CVRP. The process of tweaking solutions is described in detail. At last for evaluation of proposed approach and show the effectiveness of it, the result of running proposed approach over benchmarking data set of capacitated vehicle routing problem is illustrated
Loop quantum effect and the fate of tachyon field collapse
We study the fate of gravitational collapse of a tachyon field matter. In
presence of an inverse square potential a black hole forms. Loop quantum
corrections lead to the avoidance of classical singularities, which is followed
by an outward flux of energy.Comment: Contribution to the conference of Loops'11, Madri
Particle Swarm Optimization in Solving Capacitated Vehicle Routing Problem
The Capacitated Vehicle Routing Problem (CVRP) is an NP-Hard problem, which means it is impossible to find a polynomial time solution for it. So researchers try to reach a near optimum solution by using meta-heuristic algorithms. The aim of CVRP is to find optimum route for every vehicle and a sequence of customers, that vehicle serve. This paper proposes a method on how PSO is adjusted for a discrete space problem like CVRP. The process of tweaking solutions is described in detail. At last for evaluation of proposed approach and show the effectiveness of it, the result of running proposed approach over benchmarking data set of capacitated vehicle routing problem is illustrated
Effects of dietary aspirin supplementation on liver enzymes, immune response, cecum microflora and fatty acids profile in breast meat of broiler chickens
The present study was performed to investigate the effect of dietary aspirin (A) on broilers. A completely randomized design using 120 one-day-old male broiler chicks Ross 308, three levels of aspirin (0, 50, and 100 mg/kg) was used in 4 replicates, each including 10 chicks, during 42 days. The effects of different levels of aspirin, added to a basal diet, on blood plasma parameters, liver enzymes, immune system, cecal microflora, and fatty acids profile of breast muscle of chicks were investigated. Data analysis was performed by SAS statistical software and the comparison of the means with Duncan's test. The results showed that the effects of aspirin on blood parameters, liver enzymes of broilers (except for alkaline phosphatase which significantly reduced), the humoral immune system in response to antigen injection as sheep red blood cell (SRBC), antibody titer against Newcastle and influenza virus were not significant (P≥0.05). The highest percentage of neutrophils and eosinophils was related to this treatment. Also, aspirin treatments increased numerically the levels of unsaturated fatty acids and decreased saturated fatty acids. Moreover, aspirin led to a reduction in the population of Escherichia coli. So, based on the results of the present study, the use of 100 mg/kg aspirin in the diet of broilers is recommendable
Multi-grid Beam and Warming scheme for the simulation of unsteady flow in an open channel
In this paper, a multi-grid algorithm is applied to a large-scale block matrix that is produced from a Beam and Warming scheme. The Beam and Warming scheme is used in the simulation of unsteady flow in an open channel. The Gauss-Seidel block-wise iteration method is used for a smoothing process with a few iterations. It is also shown that the governing equations determine the type of prolongation and restriction operators for the multi-grid algorithm
Aplicación de fibra y cáscara de coco para decolorar aceite de soja
The bleaching process is an important stage in the edible oil refining operation, and is carried out by using acid-activated bleaching earths. The aim of this study was to evaluate the efficiency of coconut fiber ash, shell ash, acid-activated fiber ash and acid-activated shell ash as compared to the commercial bleaching earth in the bleaching of neutralized soybean oil. Bleaching materials were added to neutralized oil at the concentration of 1% (w/v) with agitation under vacuum at 110 °C for 30 minutes. The values for red and yellow colors, carotenoids, chlorophylls, peroxide value, p-anisidine value, free fatty acid contents, copper and iron levels of the bleached samples were determined. The results indicated that all coconut-based adsorbents have been significantly more effective than commercial bleaching earth in reducing color and the greatest reductions in carotenoid (84.25%) and chlorophyll (82.30%) contents were obtained by using acid-activated fiber ash. The peroxide value for all treatments decreased. The amounts of iron and copper as peroxide compounds decreased considerably (44.59% and 23.53%) by using acid-activated fiber ash and acid-activated shell ash, respectively. Therefore, coconut fiber and shell as agricultural wastes which have been ignored in the past might be employed as effective agents to bleach crude oils, particularly soybean oil, in refining operations.El proceso de decoloración es una etapa importante en la operación de refinación de aceites comestibles que se lleva a cabo utilizando tierras decolorantes activadas con ácido. El objetivo de este estudio fue evaluar la eficiencia de las cenizas de fibra de coco, cenizas de cáscara, cenizas de fibra activada por ácido y cenizas de cáscara activada con ácido, en comparación con la tierra decolorante comercial, en la decoloración de aceite de soja neutralizado. Los materiales de decoloración se añadieron al aceite neutralizado a una concentración del 1 % (p/v) con agitación a vacío a 110 °C durante 30 minutos. Se determinaron los valores de colores rojo y amarillo, carotenoides, clorofilas, índice de peróxido, índice de p-anisidina, contenido de ácidos grasos libres, niveles de cobre y hierro de las muestras decoloradas. Los resultados indicaron que todos los adsorbentes a base de coco han sido significativamente más efectivos que la tierra decolorante comercial para reducir el color y la mayor reducción en los contenidos de carotenoide (84,25 %) y clorofila (82,30 %) se obtuvo mediante el uso de ceniza de fibra activada con ácido. El índice de peróxido en todos los tratamientos disminuyó. Las cantidades de hierro y cobre como compuestos peroxidantes disminuyeron considerablemente (44,59% y 23,53%) al usar ceniza de fibra activada por ácido y ceniza de cáscara activada por ácido, respectivamente. Por lo tanto, la fibra y la cáscara de coco como desechos agrícolas que se han ignorado en el pasado podrían emplearse como agentes efectivos para decolorar los aceites crudos, particularmente el aceite de soja en las operaciones de refinación
Advanced Primary Lymphoma of Oral Cavity: Report of a Case
Abstract
Usually the oral manifestations of NHL are secondary to a more widespread involvement throughout
the body, however, it can rarely present as a primary lesion in the oral cavity, having 0.1% -
0.2% prevalence. In this paper we report a case of highly proliferative oral non-Hodgkin lymphoma
which presented with very mild symptoms, but had a sudden and significant progression in
less than two weeks with involvement of all four quadrants of the oral cavity.
Keywords
Lymphoma; Intra Oral Swelling; Four Quadran
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