Church-Rosser Properties of Normal Rewriting

We prove a general purpose abstract Church-Rosser result that captures most existing such results that rely on termination of computations. This is achieved by studying abstract normal rewriting in a way that allows to incorporate positions at the abstract level. New concrete Church-Rosser results are obtained, in particular for higher-order rewriting at higher types

Termination of Dependently Typed Rewrite Rules

Our interest is in automated termination proofs of higher-order rewrite rules in presence of dependent types modulo a theory T on base types. We first describe an original transformation to a type discipline without type dependencies which preserves non-termination. Since the user must reason on expressions of the transformed language, we then introduce an extension of the computability path ordering CPO for comparing dependently typed expressions named DCPO. Using the previous result, we show that DCPO is a well-founded order, behaving well in practice

Green supply chain management, supplier environmental commitment, and the roles of supplier perceived relationship attractiveness and justice. A moderated moderation analysis

A key strategic challenge for buying firms is to extend environmental management across the supply chain. This requires a strong environmental commitment on the suppliers' side. Adopting the supplier perspective, this study employs regression analysis with bootstrapping procedures to examine a contingent causal process model of the influence that two major green supply chain management practices widely adopted by buying firms in their relationships with suppliers, t, environmental assessment and environmental collaboration, exert on supplier environmental commitment, and the moderating effects of supplier perceived relationship attractiveness and supplier perceived justice. Results from a survey of 237 Chinese suppliers across multiple industries reveal that, while environmental collaboration positively influences supplier environmental commitment, the impact of environmental assessment is not significant. However, our moderation analysis shows that supplier perceived relationship attractiveness has a positive moderating effect on the influence exerted on supplier environmental commitment by both environmental assessment and collaboration, and our moderated moderation analysis reveals that both the above moderating effects are in turn positively moderated by supplier perceived justice. Focusing on the role of suppliers' perceptions, the study sheds light on the psychological context of the suppliers' choice to commit to the environmental management initiatives of their buying counterparts

Well-founded Path Orderings for Drags

International audienceThe definition herein of the Graph Path Ordering (GPO) on certain graph expressions is inspired by that of the Recursive Path Ordering (RPO), and enjoys all those properties that have made RPO popular, in particular, well-foundedness and monotonicity on variable-free terms.We are indeed interested in a generalization of algebraic expressions called operadic expressions, which are finite graphs each vertex of which is labelled by a function symbol, the arity of which governs the number of vertices it relates to in the graph. These graphs are seen here as terms with sharing and back-arrows. Operadic expressions arethemselves multiplied (an associative operation) to form monomials, which are in turn summed up (an associative commutative operation) to form polynomials. Operadic expressions and their polynomials occur in algebraic topology, and in various areas of computer science, notably concurrency and type theory. Rewriting basic operadic expressions isvery much like rewriting algebraic expressions, while rewriting their monomials and polynomials is very much like the Groebner basis theory. GPO provides an initial building block for computing with operadic expressions and their polynomials

Electron energy-loss spectroscopy and ab initio electronic structure of the LaOFeP superconductor

The electronic band structures of the LaOFeP superconductor have been calculated theoretically by the first principles method and measured experimentally by electron energy loss spectroscopy. The calculations indicate that the Fe atom in LaOFeP crystal shows a weak magnetic moment and does not form a long-range magnetic ordering. Band structure, Fermi surfaces and fluorine-doping effects are also analyzed based on the data of the density functional theory. The fine structures of the EELS data have been carefully examined in both the low loss energy region and the core losses region (O K, Fe L2,3, and La M4,5). A slight bump edge at 44 eV shows notable orientation-dependence: it can be observed in the low loss EELS spectra with q parallel to c, but becomes almost invisible in the q vertical to c spectra. Annealing experiments indicate that low oxygen pressure favors the appearance of superconductivity in LaOFeP, this fact is also confirmed by the changes of Fe L2,3 and O K excitation edges in the experimental EELS data