Understanding Of Emergent Phenomena Research Articles

Proposal for Unambiguous Electrical Detection of Spin-Charge Conversion in Lateral Spin Valves.

Efficient detection of spin-charge conversion is crucial for advancing our understanding of emergent phenomena in spin-orbit-coupled nanostructures. Here, we provide a proof of principle of an electrical detection scheme of spin-charge conversion that enables full disentanglement of competing spin-orbit coupling (SOC) transport phenomena in diffusive lateral channels, i.e., the inverse spin Hall effect and the spin galvanic effect. A suitable geometry in an applied oblique magnetic field is shown to provide direct access to SOC transport coefficients through a symmetry analysis of the output nonlocal resistance. The scheme is robust against tilting of the spin-injector magnetization, disorder, and spurious non-spin-related contributions to the nonlocal signal and can be used to probe spin-charge conversion effects in both spin-valve and hybrid optospintronic devices.

Emergence of simple patterns in many-body systems: from macroscopic objects to the atomic nucleus

Strongly correlated many-body systems often display the emergence of simple patterns and regular behaviour of their global properties. Phenomena such as clusterization, collective motion and appearance of shell structures are commonly observed across different size, time, and energy scales in our universe. Although at the microscopic level their individual parts are described by complex interactions, the collective behaviour of these systems can exhibit strikingly regular patterns. This contribution provides an overview of the experimental signatures that are commonly used to identify the emergence of shell structures and collective phenomena in distinct physical systems. Examples in macroscopic systems are presented alongside features observed in atomic nuclei. The discussion is focused on the experimental trends observed for exotic nuclei in the vicinity of nuclear closed-shells, and the new challenges that recent experiments have posed in our understanding of emergent phenomena in nuclei.

Combining state-of-the-art experiment and ab initio calculations for a better understanding of the interplay between valence, magnetism and structure in Eu compounds at high pressure

ABSTRACTWe describe how first principle calculations can play a key role in the interpretation of X-ray absorption near-edge structure (XANES) and X-ray magnetic circular dichroism (XMCD) spectra for a better understanding of emergent phenomena in condensed matter physics at high applied pressure. Eu compounds are used as case study to illustrate the advantages of this methodology, ranging from studies of electronic charge transfer probed by quadrupolar and dipolar contributions, to accurately determining electronic valence, and to inform about the influence of pressure on RKKY interactions and magnetism. This description should help advance studies where the pressure dependence of XANES and XMCD data must be tackled with the support of theoretical calculations for a proper understanding of the electronic properties of materials.

Verbatim and Semantic Imitation in Indexing Resources on the Web: A Fuzzy‐trace Account of Social Tagging

SummarySocial tagging is a widespread phenomenon on the Web allowing users to tag resources, such as photos, by freely chosen labels. Imitation of other users' tagging behavior is deemed to increase the inter‐individual consistency of tag assignments. Both verbatim and semantic mechanisms have been proposed where the first case suggests reuse of the exact words and the second reuse of the concept without necessarily the word form. Here, we present a multinomial model of assigning tags that integrates these perspectives. On the basis of the fuzzy‐trace theory, the model includes separate parameters for the retrieval of verbatim and gist traces of encountered tags. Results of two experiments demonstrate that both types of memory traces contribute substantially and independently to tag productions. We conclude that the imitation of tags may be explained within one fuzzy‐trace framework that contributes to our understanding of emergent phenomena in social information systems. Copyright © 2014 John Wiley & Sons, Ltd.

Analysis of the Emergence in Swarm Model Based on Largest Lyapunov Exponent

Emergent behaviors of collective intelligence systems, exemplified by swarm model, have attracted broad interests in recent years. However, current research mostly stops at observational interpretations and qualitative descriptions of emergent phenomena and is essentially short of quantitative analysis and evaluation. In this paper, we conduct a quantitative study on the emergence of swarm model by using chaos analysis of complex dynamic systems. This helps to achieve a more exact understanding of emergent phenomena. In particular, we evaluate the emergent behaviors of swarm model quantitatively by using the chaos and stability analysis of swarm model based on largest Lyapunov exponent. It is concluded that swarm model is at the edge of chaos when emergence occurs, and whether chaotic or stable at the beginning, swarm model will converge to stability with the elapse of time along with interactions among agents.

Responding to the Tsunami

Revision with unchanged content. December 26, 2004, the East Coast of India reverberates with church bells ringing, vendors selling their wares, children’s voices, all oblivious to the fact that an unprecedented disaster, in the guise of a tsunami, was about to befall them. When a disaster of such magnitude hits a community, altruism triggers the need to get involved, and so the locals did. The Villagers and Administration in the State of Tamil Nadu, India, swung into action and res­ponded splendidly to the disastrous happenings that fateful day. Documen­ted here, are their ad hoc groupings, organizations and structures that ap­peared out of thin air and adequately managed tasks delivered by a disaster of such extreme magnitude. This book hopes to reach the administration of coastal towns and villages in India and around the world as well as to practi­tioners of emergency management. It hopes to serve not as a guide book or as an agenda to disaster response, but rather a documentation of emergent structures that made the aftermath of the disaster manageable. This work is not an end in itself but hopes to make strides in the right direction toward a better understanding of emergent phenomena in the wake of disasters.

Explaining systems: Investigating middle school students' understanding of emergent phenomena

Science, as with all cognitive activities, is fundamentally a matter of interpretation, sense-making, and explanation. This study focused on a small group of middle school students as they developed understanding of a particular type of phenomena: emergent systems. Such systems are notable in that macro-level properties emerge as the result of micro-level interactions between system components. I describe students' initial understanding of emergent systems, as well as the ways in which their thinking came to reflect the following heuristics: (a) recognition that there may not be a singular causal force underlying the system; (b) distinguishing between micro- and macro-levels of analysis; and (c) comprehending that even small changes at the micro-level can have significant effects at the macro-level (Resnick, 1994). I conclude by considering some implications for science education. © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 784–806, 2000