Large-scale computing often consists of many speculative tasks to test hypotheses, search for insights, and review potentially finished products. For example, speculative tasks are issued by bioinformaticists comparing DNA sequences and computer graphics artists adjusting scene properties. This paper promotes a new computing model for shared clusters and grids in which researchers and end-users...

†Department of Mathematics, Statistics and Computer Science, College of Basic Sciences and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar-263 145, India ‡Institute of Systems Science, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences, Beijing 100080, China §Department of Management Sciences, City University of Hong Kong, Tat Chee Avenue, Kowloon...

Inspired by a similar use in provability logic, formulas pÂB q and p <B q are introduced in the existing logical framework for discussing beliefs to express that the strength of belief in p is greater than (or equal to) that in q. This explicit mention of the comparison in the logical language aids in defining several other concepts in a uniform way, viz. older and rather clear concepts like th...

In many physical situations, a few specific eigenvalues of a large sparse generalized eigenvalue problem Ax = λBx are needed. If exact linear solves with A − σB are available, implicitly restarted Arnoldi with purification is a common approach for problems where B is positive semidefinite. In this paper, a new approach based on implicitly restarted Arnoldi will be presented that avoids most of ...