In this paper the performance of the proposed DLMT and CLMT algorithms are compared. These proposed algorithms tend to extend the node lifetime. Decentralized lifetime maximizing tree(DLMT) features in nodes with higher energy to be chosen as data aggregating parents while Centralized Lifetime Maximizing Tree(CLMT) features with the identification of the bottleneck node to collect data in a cen...

In object based data models complex values such as tuples or sets have no special status and must therefore be represented by objects As a consequence di erent objects may represent the same value i e duplicates may occur This paper contains a study of the precise expressive power required for the representation of complex values in typical object based data models supporting rst order queries ...

data mining techniques have been used widely in the area of customer relationship management (crm). in this study, we have applied data mining techniques to address a problem in business-to-business (b2b) setting. in a manufacturer-retailer-consumer chain, a manufacturer should improve its relationship with retailers to continue its business. segmentation is a useful tool for identifying groups...

in the last decade, decrease of the wear rate, increase in the axel load, and the velocity of the trains have changed the main damage mechanism of railway wheels from wear to rolling contact fatigue (rcf). rcf may lead to surface and subsurface cracks. the interaction between wear and rcf, removes the surface cracks, but the subsurface crack propagate gradually, and may lead to deeper and more ...

Over the last few years a theoretical treatment for the weak decays of heavy-flavour hadrons has been developed that is genuinely based on QCD. Its methodology is described as it applies to total lifetimes, and the underlying theoretical issues are discussed. Theoretical expectations are compared with present data. One discrepancy emerges: the beauty baryon lifetime appears to be significantly ...

Within the class of “determinate” object-creating database transformations, identified by Abiteboul and Kanellakis, a natural proper subclass consists of the so-called “constructive” transformations. A determinate transformation is constructive if its input-output pairs satisfy a condition discovered by Jan Paredaens. In this note we point out that when object creation is “tree-structured,” as ...

The formal description of the semantics of object-oriented data models is still an open problem. Some characteristic features of object-oriented data models, such as methods and inheritance, involve investigating data and schema. Therefore they can not be handled straightforwardly with rst order logic. As an alternative, we propose the evolving algebra approach to specify the formal semantics o...

Editorial – Cohabitation, marriage and separation: contrasts in Europe • Premarital cohabitation: more common in the north than in the south p. 2 • Cohabitation leads less often to marriage p. 2 • Fewer men and women are marryingp. 2 • Unions are more short-lived p. 3 • Several unions in a lifetime: a general trend? p. 4 • Box: Study population p. 4 C O N TE N TS are not marrying at all. Unions...

In today's fiercely competitive products market, product warranty has started playing an important role. The warranty period offered by the manufacturer/dealer has been progressively increasing since the beginning of the 20th Century. Currently, a large number of products are being sold with long-term warranty policies in the form of extended warranty, warranty for used products, service contra...