2,401 research outputs found
Catalysts for electrochemical generation of oxygen
Several aspects of the electrolytic evolution of oxygen for use in life support systems are analyzed including kinetic studies of various metal and nonmetal electrode materials, the formation of underpotential films on electrodes, and electrode surface morphology and the use of single crystal metals. In order to investigate the role of surface morphology to electrochemical reactions, a low energy electron diffraction and an Auger electron spectrometer are combined with an electrochemical thin-layer cell allowing initial characterization of the surface, reaction run, and then a comparative surface analysis
Nontrivial and Universal Helping for Wait-Free Queues and Stacks
This paper studies two approaches to formalize helping in wait-free implementations of shared objects. The first approach is based on operation valency, and it allows us to make the important distinction between trivial and nontrivial helping. We show that a wait-free implementation of a queue from common2 objects (e.g., Test&Set) requires nontrivial helping. In contrast, there is a wait-free implementation of a stack from Common2 objects with only trivial helping. This separation might shed light on the difficulty of implementing a queue from Common2 objects.
The other approach formalizes the helping mechanism employed by Herlihy\u27s universal wait-free construction and is based on having an operation by one process restrict the possible linearizations of operations by other processes. We show that objects possessing such universal helping can be used to solve consensus
Tunable intervalence charge transfer in ruthenium Prussian blue analogue enables stable and efficient biocompatible artificial synapses
Emerging concepts for neuromorphic computing, bioelectronics, and
brain-computer interfacing inspire new research avenues aimed at understanding
the relationship between oxidation state and conductivity in unexplored
materials. Here, we present ruthenium Prussian blue analogue (RuPBA), a mixed
valence coordination compound with an open framework structure and ability to
conduct both ionic and electronic charge, for flexible artificial synapses that
reversibly switch conductance by more than four orders of magnitude based on
electrochemically tunable oxidation state. Retention of programmed states is
improved by nearly two orders of magnitude compared to the extensively studied
organic polymers, thus reducing the frequency, complexity and energy costs
associated with error correction schemes. We demonstrate dopamine detection
using RuPBA synapses and biocompatibility with neuronal cells, evoking
prospective application for brain-computer interfacing. By application of
electron transfer theory to in-situ spectroscopic probing of intervalence
charge transfer, we elucidate a switching mechanism whereby the degree of mixed
valency between N-coordinated Ru sites controls the carrier concentration and
mobility, as supported by DFT
DepAnn - An Annotation Tool for Dependency Treebanks
DepAnn is an interactive annotation tool for dependency treebanks, providing
both graphical and text-based annotation interfaces. The tool is aimed for
semi-automatic creation of treebanks. It aids the manual inspection and
correction of automatically created parses, making the annotation process
faster and less error-prone. A novel feature of the tool is that it enables the
user to view outputs from several parsers as the basis for creating the final
tree to be saved to the treebank. DepAnn uses TIGER-XML, an XML-based general
encoding format for both, representing the parser outputs and saving the
annotated treebank. The tool includes an automatic consistency checker for
sentence structures. In addition, the tool enables users to build structures
manually, add comments on the annotations, modify the tagsets, and mark
sentences for further revision
Proceedings
Proceedings of the NODALIDA 2011 Workshop
Constraint Grammar Applications.
Editors: Eckhard Bick, Kristin Hagen, Kaili Müürisep, Trond Trosterud.
NEALT Proceedings Series, Vol. 14 (2011), vi+69 pp.
© 2011 The editors and contributors.
Published by
Northern European Association for Language
Technology (NEALT)
http://omilia.uio.no/nealt .
Electronically published at
Tartu University Library (Estonia)
http://hdl.handle.net/10062/19231
Analysis of resource control in nondeterministic mobile ad hoc network systems : an unmanned aerial vehicle example
This thesis utilized known information about a dynamic graph in which resource needy nodes act as relays for control information to a supplier node in order to characterize system performance and analyze the effects of change on the system. The connectivity, or information sharing, was based on distance and since every node moved around a defined space, the connectivity of the graph changed constantly. Several different controllers and scenarios are investigated in order to extract the uniqueness in each performance curve which created a better understanding of this near nondeterministic system. One such application for this dynamic system is the automation of Unmanned Aerial Vehicles (UAVs). This paper utilizes the UAV example in order to bring life, and motivate this research. Note that there are many other applications and problems with similar voids in understanding that this approach could be applied. The United States Department of Defense is increasingly utilizing Unmanned Aerial Vehicles (UAVs) to support current operations. As of August 2010, there were 207 Intelligence, Surveillance, and Reconnaissance (ISR) sorties flown per day to provide essential battlespace situational awareness for Operation Enduring Freedom and Operation Iraqi Freedom [1]. This paper proposes an implementation of an autonomous UAV network that assumes cutting edge technologies can be combined to provide infinite\u27 ISR over a given area. The particular dynamics of this problem are characterized using systems techniques while changes to the performance factors on the system are found using information about the root system.\u2
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