Identifying Collective Modes via Impurities in the Cuprate Superconductors

We show that the pinning of collective charge and spin modes by impurities in the cuprate superconductors leads to qualitatively different fingerprints in the local density of states (LDOS). In particular, in a pinned (static) spin droplet, the creation of a resonant impurity state is suppressed, the spin-resolved LDOS exhibits a characteristic spatial pattern, and the LDOS undergoes significant changes with increasing magnetic field. Since all of these fingerprints are absent in a charge droplet, impurities are a new probe for identifying the nature and relative strength of collective modes.Comment: 4 pages, 4 figure

Supply Chain Modifications to Improve Additive Manufacturing

Additive manufacturing (AM) offers unique production characteristics which among those, toollessness and production of complex geometries are potentially significant to operations efficiency. Previous research has illustrated the potential sufficiency of this technology to affect the supply chains‟ arrangements and enabling decentralized production configurations. While, one of the important advantages of AM enabled distributed production is the increased flexibility, which is a necessity in today‟s competitive and ever changing global supply chains, number of obstacles have kept this method from wide implementation. In this paper, we study the possible supply chain modifications to decrease the cost of an AM-enabled decentralized production system. In other words, we perform a cost-benefit analysis on various AM supply chain strategies in a spare parts context to realize the independent operational factors affecting the implementation cost of additive manufacturing. Moreover, we analyze the ways to adapt the supply chain management to enable full potential of AM considering the present technology.Mechanical Engineerin

On the generalized linear equivalence of functions over finite fields

In this paper we introduce the concept of generalized linear equivalence between functions defined over finite fields; this can be seen as an extension of the classical criterion of linear equivalence, and it is obtained by means of a particular geometric representation of the functions. After giving the basic definitions, we prove that the known equivalence relations can be seen as particular cases of the proposed generalized relationship and that there exist functions that are generally linearly equivalent but are not such in the classical theory. We also prove that the distributions of values in the Difference Distribution Table (DDT) and in the Linear Approximation Table (LAT) are invariants of the new transformation; this gives us the possibility to find some Almost Perfect Nonlinear (APN) functions that are not linearly equivalent (in the classical sense) to power functions, and to treat them accordingly to the new formulation of the equivalence criterion