Dispersed air flotation of fine particles

Imperial Users onl

Rearranging trees for robust consensus

In this paper, we use the H2 norm associated with a communication graph to characterize the robustness of consensus to noise. In particular, we restrict our attention to trees and by systematic attention to the effect of local changes in topology, we derive a partial ordering for undirected trees according to the H2 norm. Our approach for undirected trees provides a constructive method for deriving an ordering for directed trees. Further, our approach suggests a decentralized manner in which trees can be rearranged in order to improve their robustness.Comment: Submitted to CDC 201

Structures And Strategies Of Attentional Deployment In Schizophrenia

Inconsistent findings within three areas of schizoprenia research--processing of stimulus characteristics, attention, and hemispheric functional asymmetry--suggested the importance of examining the attentional resources associated with the cerebral hemispheres among schizophrenics. A cognitive task battery was developed which assessed the functioning of the left and right hemispheres under varying attentional loads. This battery was administered to paranoid and nonparanoid schizophrenics, and three control groups. Error rate and reaction time were monitored. It was found that the schizophrenics, particularly the nonparanoids, displayed evidence of a generalized decrease in available resources across attentional pools. In addition, overall reaction time data suggested the existence of internally generated attentional loads associated with the left hemisphere in paranoids, and the right hemisphere in nonparanoids. These loads appeared to affect hemispheric functioning without interacting with the differential sensitivity of the hemispheres to stimulus characteristics. The findings were speculatively interpreted as indicating the deployment of anomalous attentional strategies by schizophrenics, rather than directly resulting from defective cognitive structures

A Course in Legal English and U.S. Law for Undergraduate Japanese Law Students

In this paper, I discuss the design of a Legal English and U.S. Law course for undergraduate Japanese law students visiting for a semester at the University of Wisconsin-Milwaukee’s English Language Academy. I review how I went about analyzing the students’ needs and wants and the factors affecting their motivation. I explain my philosophy of second language teaching, in particular, that second language teaching should contain an element of play. I describe how I sought to introduce a play element in the course through such techniques as watching law-related movies, role play activities, Kahoot quizzes, and pronunciation drills. Course design included, as well, vocabulary study, readings of authentic legal texts as well as teacher-prepared writings, guest speakers, and field trips. I report the students’ reactions to the course, as indicated in a mid-semester survey

Starling flock networks manage uncertainty in consensus at low cost

Flocks of starlings exhibit a remarkable ability to maintain cohesion as a group in highly uncertain environments and with limited, noisy information. Recent work demonstrated that individual starlings within large flocks respond to a fixed number of nearest neighbors, but until now it was not understood why this number is seven. We analyze robustness to uncertainty of consensus in empirical data from multiple starling flocks and show that the flock interaction networks with six or seven neighbors optimize the trade-off between group cohesion and individual effort. We can distinguish these numbers of neighbors from fewer or greater numbers using our systems-theoretic approach to measuring robustness of interaction networks as a function of the network structure, i.e., who is sensing whom. The metric quantifies the disagreement within the network due to disturbances and noise during consensus behavior and can be evaluated over a parameterized family of hypothesized sensing strategies (here the parameter is number of neighbors). We use this approach to further show that for the range of flocks studied the optimal number of neighbors does not depend on the number of birds within a flock; rather, it depends on the shape, notably the thickness, of the flock. The results suggest that robustness to uncertainty may have been a factor in the evolution of flocking for starlings. More generally, our results elucidate the role of the interaction network on uncertainty management in collective behavior, and motivate the application of our approach to other biological networks.Comment: 19 pages, 3 figures, 9 supporting figure