Dynamics of localized spins coupled to the conduction electrons with charge/spin currents

The effects of the charge/spin currents of conduction electrons on the dynamics of the localized spins are studied in terms of the perturbation in the exchange coupling $J_{K}$ between them. The equations of motion for the localized spins are derived exactly up to $O(J_{K}^2)$, and the equations for the two-spin system is solved numerically. It is found that the dynamics depends sensitively upon the relative magnitude of the charge and spin currents, i.e., it shows steady state, periodic motion, and even chaotic behavior. Extension to the multi-spin system and its implications including possible ``spin current detector'' are also discussed.Comment: 5 pages, 4 figures, REVTe

Drawing close: on visual engagements in fieldwork, drawing workshops and the anthropological imagination

Participatory visual methods are becoming the new hype in anthropology. Researchers tend to present participatory visual methods as attractive approaches to not only promote innovative research that engages informants in original and collaborative ways but to engage students eager to find bridges between the academic world and a world progressively addicted to visual consumerism. Unlike photographing and filming, doodling-sketching-drawing – participatory or not – is more about linear image mental processing and communicating (and thus somewhat akin to handwriting, lack of linguistic encoding and propositionality notwithstanding) than an “objective” visual method. Based on discussions from a workshop dedicated to “ethnographic drawing” in the University of Aberdeen, we propose to tackle some of the features of the drawing practice, hoping that its much-misunderstood potential as a knowledge tool helps us reconsider what anthropological understanding is.info:eu-repo/semantics/publishedVersio

Disclosure of environmental matters - Galp Energy

There is a growing number of companies expressing social concerns where environmental worries are also included. Even before legal obliga-tion of environmental disclosures, companies already used to adopt an active stance to safeguard their reputation. However, risk events may have negative impacts on companies’ legitimacy, making it necessary to implement strategies to repair/recover the damaged reputation. This study analyses the annual reports from 2001 to 2011 of the largest Por-tuguese oil company - Galp Energia - in the view of the occurrence of negative events, which, consequently, may have affected the company's reputation. Empirically, legitimacy theory can explain the implementa-tion of strategies to repair reputation. Within this context, most of the existing research is based on common-law countries, with little literature grounded on code-law countries, such as Portugal. Findings have shown that Galp Energia has great concerns about the external perception of society. The company acts immediately after risk events, implementing strategies to minimise the risk impact, especially through the use of cor-rective actions.info:eu-repo/semantics/acceptedVersio

Gaseous Electronics

Contains reports on two research projects.Joint Services Electronics Program (Contract DA36-039-AMC-03200(E)