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...

Assessment of exposure to airborne endotoxins has been studied for several years, especially in occupational environments, but a large number of procedures are used for sampling and analysis. This lack of standardization makes it very difficult to compare results and set internationally accepted threshold limit values (TLVs) or occupational exposure limits (OELs) for endotoxin exposure. This pa...

We extend a result of Ramaré & Rumely, 1996 [3] about Chebyshev function θ in arithmetic progressions. We find a map ε(x) such that | θ(x; k, l) − x/φ(k) |< xε(x) and ε(x) = O ( 1 lna x ) (∀a > 0) whereas ε(x) is a constant in [3]. Now we are able to show that | θ(x; 3, l)− x/2 |< 0.262 x lnx and, for x > 151, π(x; 3, l) > x 2 lnx .

Fuzzy K-means clustering algorithm is a popular approach for exploring the structure of a set of patterns, especially when the clusters are overlapping or fuzzy. However, the fuzzy K-means clustering algorithm cannot be applied when the real-life data contain missing values. In many cases, the number of patterns with missing values is so large that if these patterns are removed, then sufficient...

In this paper, we establish some new recurrence relations between the single moments of record values from the modified Weibull distribution as well as between the double moments. Next, we show that the results for the record values from the Weibull distribution obtained by Balakrishnan and Chan (1993) can be derived from our results as special cases. In addition, we deduce some new recurrence ...

Let (Xn) be a sequence of independent and identically distributed random variables, with common absolutely continuous distribution F . An observation Xn is a near-record if Xn ∈ (Mn−1 − a, Mn−1], where Mn = max{X1, . . . , Xn} and a > 0 is a parameter. We analyze the point process η on [0,∞) of near-record values from (Xn), showing that it is a Poisson cluster process. We derive the probability...