We have obtained empirical relations between the p-mode frequency shift and the change in solar activity indices. The empirical relations are determined on the basis of frequencies obtained from BBSO and GONG stations during solar cycle 22. These relations are applied to estimate the change in mean frequency for the cycle 21 and 23. A remarkable agreement between the calculated and observed fre...

We have obtained empirical relations between the p-mode frequency shift and the change in solar activity indices. The empirical relations are determined on the basis of frequencies obtained from BBSO and GONG stations during solar cycle 22. These relations are applied to estimate the change in mean frequency for the cycle 21 and 23. A remarkable agreement between the calculated and observed fre...

In a standard cluster analysis, such as k-means, in addition to clusters locations and distances between them, it’s important to know if they are connected or well separated from each other. The main focus of this paper is discovering the relations between the resulting clusters. We propose a new method which is based on pairwise overlapping k-means clustering, that in addition to means of clus...

after establishment of the world trade organization (wto) in 1995, not only all countries around the world had to receive progressively the wto accession but also those that had higher economic potentials benefited further advantages from their memberships. one goal which has been followed by the wto has relied on economic convergence. it is now a time to ask whether convergence in monetary po...

introduction: evaporation and evapotranspiration are two major components of hydrological cycle which are very important for agricultural studies as well as water resources management. so far, various methods have been addressed for the estimation of daily reference crop evapotranspiration (et0). among them, fao penman-montieth 56 (pmf-56) (allen et al., 1998) is widely used as a standard metho...

Whether or not a formal approach to spatial relations is a cognitively adequate (the term will be explicated in this paper) model of human spatial knowledge is more often based on the intuition of the researchers than on empirical data. In contrast, the research reported here is concerned with an empirical assessment of one of the three general classes of spatial relations, namely topological k...

The concept of alliance or preferably ‘alignment’, as I shall explain below – is central to the conduct of international politics, and thus the discipline of International Relations (IR). Duffield et al. (2008: 291) identify that ‘Alliances are one of the most significant phenomena in security studies and world politics more generally’, while Modelski (1963: 773) considers them ‘one of a dozen ...