regarding the important role of health in economic growth and development, the purpose of the present paper is to investigate the impact of life expectancy, as the most important indicator of health, on economic growth in iran during 1965-2009. the estimated smooth transition regression (str) model supports a nonlinear threshold behavior in the relationship between life expectancy and economic ...

In this paper, we investigate an optimization of threshold level with energy detection to improve the spectrum sensing performance. Determining threshold level to minimize spectrum sensing error both reduces collision probability with primary user and enhances usage level of vacant spectrum, resulting in improving total spectrum efficiency. However, when determining threshold level, spectrum se...

2-D threshold function f is a function defined on the integer interior of a rectangular area [0, m] × [0, n] on a plane and takes values from the set {0, 1} such that there is a straight line separating the pre-images f −1 (0) and f −1 (1). For the number of such functions only asymptotic bounds were known. We give an exact formula for the number of 2-D threshold functions and derive an asympto...

The multiple-look notion holds that the difference limen (DL) decreases with multiple observations. We investigated this notion for temporal discrimination in isochronous sound sequences. In Experiment 1, we established a multiple-look effect when sequences comprised nine standard time intervals (S) followed by an increasing number of comparison time intervals (C), but no multiple-look effect w...

A model has been used to simulate potassium (K) uptake by wheat in a pot culture experiment. Three soils from India, namely Alfisol, Inceptisol and Vertisol, were differentially K exhausted by Sudan grass (Surghum vulgare var. Sudanensis) for a period of 280 days and were used to simulate potassium uptake by wheat (Triticum aestivum) and also to predict the amounts of K released or fixed during...

The negative impact of man-made noise on the hearing of odontocetes has attracted considerable recent attention. In the majority of studies, permanent or temporary reductions in sensitivity, known as permanent or temporary threshold shift (PTS or TTS, respectively), have been investigated. In the present study, the effects of a fatiguing sound on the hearing of a beluga whale, Delphinapterus le...

In order to avoid or predict cavitation erosion, it is necessary to know resistance of materials against to cavitation impacts. The cavitation impacts, which are larger than certain threshold level, only affect cavitation erosion of materials. In the present paper, existence of the threshold level was revealed experimentally. The threshold level of material is a new parameter to predict the cav...