Origin of spin incommensurability in hole-doped S=1 Y2-xCaxBaNiO5 chains

Spin incommensurability (IC) has been recently experimentally discovered in the hole-doped Ni-oxide chain compound Y2-xCaxBaNiO5 [G. Xu et al., Science 289, 419 (2000)]. Here a two orbital model for this material is studied using computational techniques. Spin IC is observed in a wide range of densities and couplings. The phenomenon originates in antiferromagnetic correlations across holes dynamically generated to improve hole movement, as it occurs in the one-dimensional Hubbard model and in recent studies of the two-dimensional extended t-J model. The close proximity of ferromagnetic and phase-separated states in parameter space is also discussed.

Extending lean manufacturing in supply chains: a successful case in Brazil

Purpose – The purpose of this paper is to present the results of a success story involving the extending of lean manufacturing practices between a focal firm and its supplier, both located in Brazil, thereby configuring a case of excellence. Design/methodology/approach – An in-depth case study was conducted involving two companies: Company A, focal, leader in its segment, located in Brazil; and Company B, Company A's supplier, also located in Brazil. Findings – Results indicate there are several mechanisms for extending lean manufacturing practices in the supply chain, such as workshops, training, and integrated teams. These mechanisms are shown and guidelines are also introduced for companies seeking to successfully extend lean manufacturing practices. Originality/value – An original use of define, measure, analyze, improve, control for structuring the extending of lean manufacturing practices to suppliers and, consequently, the importance of the lean six-sigma relationship in this context. Furthermore, the guidelines introduced serve as a benchmark for other companies interested in the topic.