The preconditioning of linear least-squares problems is a hard task. The linear model underpinning least-squares problems, that is the overdetermined matrix defining it, does not have the properties of differential problems that make standard preconditioners effective. Incomplete Cholesky techniques applied to the normal equations do not produce a well conditioned problem. We attempt to remove ...

This paper presents a comprehensive classification of basic illocutions in Modern Greek, extracted following the linguistic choices speakers make when they formulate an utterance, provided such choices form part of a language’s grammar. Our approach lies on the interface between Morphosyntax, Pragmatics and Phonology and allows for basic illocutions to be established depending on the particular...

Investigating relationships in information is an important component of statistical and spatial analysis. Clustering techniques have proven to be effective in helping to find patterns or relationships which otherwise may not have been detected. One of the most popular partitioning based clustering approaches is k-means. In this paper we explore the application of the k-means approach to spatial...

BACKGROUND Early signs interventions show promise but could be further developed. A recent review suggested that 'basic symptoms' should be added to conventional early signs to improve relapse prediction. This study builds on preliminary evidence that basic symptoms predict relapse and aimed to: 1. examine which phenomena participants report prior to relapse and how they describe them; 2. deter...

for identifying drought tolerance genotypes 29 wheat genotypes as cultivar factor and irrigation and non irrigation treatments as an irrigation factor in a split block design with 3 blocks were planted at a research filed of college of agriculture, tehran university, iran. there was a low and non significant correlation (r=0.35) between yield at non irrigating (ys) and yield at irrigating (yp) ...