4,746 research outputs found
PSO based Neural Networks vs. Traditional Statistical Models for Seasonal Time Series Forecasting
Seasonality is a distinctive characteristic which is often observed in many
practical time series. Artificial Neural Networks (ANNs) are a class of
promising models for efficiently recognizing and forecasting seasonal patterns.
In this paper, the Particle Swarm Optimization (PSO) approach is used to
enhance the forecasting strengths of feedforward ANN (FANN) as well as Elman
ANN (EANN) models for seasonal data. Three widely popular versions of the basic
PSO algorithm, viz. Trelea-I, Trelea-II and Clerc-Type1 are considered here.
The empirical analysis is conducted on three real-world seasonal time series.
Results clearly show that each version of the PSO algorithm achieves notably
better forecasting accuracies than the standard Backpropagation (BP) training
method for both FANN and EANN models. The neural network forecasting results
are also compared with those from the three traditional statistical models,
viz. Seasonal Autoregressive Integrated Moving Average (SARIMA), Holt-Winters
(HW) and Support Vector Machine (SVM). The comparison demonstrates that both
PSO and BP based neural networks outperform SARIMA, HW and SVM models for all
three time series datasets. The forecasting performances of ANNs are further
improved through combining the outputs from the three PSO based models.Comment: 4 figures, 4 tables, 31 references, conference proceeding
Universal scaling in BCS superconductivity in two dimensions in non-s waves
The solutions of a renormalized BCS model are studied in two space dimensions
in , and waves for finite-range separable potentials. The gap
parameter, the critical temperature , the coherence length and the
jump in specific heat at as a function of zero-temperature condensation
energy exhibit universal scalings. In the weak-coupling limit, the present
model yields a small and large appropriate to those for high-
cuprates. The specific heat, penetration depth and thermal conductivity as a
function of temperature show universal scaling in and waves.Comment: 11 pages, LATEX, 4 postscript figures embedded using eps
Quantum scattering in one dimension
A self-contained discussion of nonrelativistic quantum scattering is
presented in the case of central potentials in one space dimension, which will
facilitate the understanding of the more complex scattering theory in two and
three dimensions. The present discussion illustrates in a simple way the
concept of partial-wave decomposition, phase shift, optical theorem and
effective-range expansion.Comment: 8 page
Effect of Irrigation and Potash Levels on Keeping Quality of Potato
Irrigation and fertilizer are the most dominating factors, in deciding the keeping quality of potato. It is, therefore, essential to formulate the efficient, reliable and economically viable irrigation management strategy with the use of potassium nutrient in order to produce better keeping quality. The investigation comprising four levels of irrigation (25, 30, 35 and 40 mm CPE (Cumulative pan evaporation) and four levels of potash (0, 100, 125 and 150 kg/ha) was carried out at Research Farm of the Department of Vegetable Science, CCS Haryana Agricultural University, (Haryana) Hisar, India during two years to find out the optimum level of irrigation and potash for obtaining higher yield of potatoes with better keeping quality at ambient room temperature. The potato variety used for the investigation was Kufri Bahar. The treatments were laid out in a split plot design with three replications. The increasing levels of irrigation and potash showed significant improvement in keeping quality parameters of potato. Likewise, the values for physiological loss in weight and decay loss of potato tubers (%) at 15, 30, 45 and 60 days after harvest were the lowest with irrigation level 40 mm CPE and application of potash @ 150 kg/ha. The two years results suggest that the irrigation level 40 mm CPE along with potash @ 150 kg/ha has shown the best treatment combination for the storage of potato at ambient room temperature under semiarid conditions of Hisar (Haryana)
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