Communication: Electronic flux induced by crossing the transition state

We present a new effect of chemical reactions, e.g., isomerizations, that occurs when the reactants pass along the transition state, on the way to products. It is based on the well-known fact that at the transition state, the electronic structure of one isomer changes to the other. We discover that this switch of electronic structure causes a strong electronic flux that is well distinguishable from the usual flux of electrons that travel with the nuclei. As a simple but clear example, the effect is demonstrated here for bond length isomerization of Na2 (21Σ+u), with adiabatic crossing the barrier between the inner and outer wells of the double minimum potential that support different “Rydberg” and “ionic” type electronic structures, respectively

A practical inquiry on patterns of corrective feedback and modified output in an adult high-beginning ESL grammar class

1 online resource (PDF, 73 pages). Submitted May, 2013 as a Plan B paper in partial fulfillment of the requirements for a master's degree in English as a Second Language from the University of Minnesota.Corrective feedback has been accorded an important role in second language (L2) acquisition (Chaudron, 1988; Long, 1996), partly because it may allow opportunities for modified output, a process that is claimed to benefit L2 development (Swain, 1985, 1995). Classroom studies have revealed different feedback types associated with different levels of success in inviting modified output depending on various mediating factors, such as characteristics of feedback, learner differences and instructional contexts. The present descriptive self-study examined patterns of corrective feedback and learner responses in an adult high-beginning ESL grammar class. The findings showed that recasts were the most frequent yet least effective feedback type, often followed by a majority of peer-initiated and teacher-initiated topic continuation. The findings also revealed some error patterns in my responses to students’ non-target utterances, but students did not appear to notice my errors. These results suggest some pedagogical implications with respect to my role as a facilitator and monitor as well as raising students’ awareness of self- and peer-corrections. Keywords: self-study, corrective feedback, modified output, ESL, gramma

Panoramic Annular Localizer: Tackling the Variation Challenges of Outdoor Localization Using Panoramic Annular Images and Active Deep Descriptors

Visual localization is an attractive problem that estimates the camera localization from database images based on the query image. It is a crucial task for various applications, such as autonomous vehicles, assistive navigation and augmented reality. The challenging issues of the task lie in various appearance variations between query and database images, including illumination variations, dynamic object variations and viewpoint variations. In order to tackle those challenges, Panoramic Annular Localizer into which panoramic annular lens and robust deep image descriptors are incorporated is proposed in this paper. The panoramic annular images captured by the single camera are processed and fed into the NetVLAD network to form the active deep descriptor, and sequential matching is utilized to generate the localization result. The experiments carried on the public datasets and in the field illustrate the validation of the proposed system.Comment: Accepted by ITSC 201

Nuclear versus electronic ring currents in oriented torsional molecules induced by magnetic fields. I. Nuclear currents of toluene

We develop the theory of nuclear ring currents induced by external magnetic fields in torsional molecules. The theory is applied to toluene, whose torsion axis is oriented along the magnetic field. We obtain magnetically induced diatropic and paratropic contributions to the nuclear ring current flowing in the classical and nonclassical directions, respectively. In the electronic and torsional and rotational ground state of toluene, the strengths of the diatropic and paratropic nuclear ring-current susceptibilities are -19.9 pA/T and 0.4 fA/T, respectively, yielding a net current strength of -19.9 pA/T. The paratropic contribution is very small because the torsional barrier of toluene is very low. The study suggests criteria for observing significant magnetically induced nuclear ring currents in torsional molecules whose axis is oriented along the magnetic field.Peer reviewe

Autopilot Design for Unmanned Surface Vehicle based on CNN and ACO

There is a growing concern to design intelligent controllers for autopiloting unmanned surface vehicles as solution for many naval and civilian requirements. Traditional autopilot’s performance declines due to the uncertainties in hydrodynamics as a result of harsh sailing conditions and sea states. This paper reports the design of a novel nonlinear model predictive controller (NMPC) based on convolutional neural network (CNN) and ant colony optimizer (ACO) which is superior to a linear proportional integral-derivative counterpart. This combination helps the control system to deal with model uncertainties with robustness. The results of simulation and experiment demonstrate the proposed method is more efficient and more capable to guide the vehicle through LOS waypoints particularly in the presence of large disturbances