646 research outputs found
A-posteriori provenance-enabled linking of publications and datasets via crowdsourcing
This paper aims to share with the digital library community different opportunities to leverage crowdsourcing for a-posteriori capturing of dataset citation graphs. We describe a practical approach, which exploits one possible crowdsourcing technique to collect these graphs from domain experts and proposes their publication as Linked Data using the W3C PROV standard. Based on our findings from a study we ran during the USEWOD 2014 workshop, we propose a semi-automatic approach that generates metadata by leveraging information extraction as an additional step to crowdsourcing, to generate high-quality data citation graphs. Furthermore, we consider the design implications on our crowdsourcing approach when non-expert participants are involved in the process<br/
Desulfo-glucosinolate sulfotransferases isolated from several Arabidopsis thaliana ecotypes differ in their sequence and enzyme kinetics
The goal was to investigate whether the diverse glucosinolate (Gl) profiles described for different Arabidopsis thaliana (L.) Heynh. ecotypes are at least partially shaped by the kinetic properties of sulfotransferases (SOTs) (EC 2.8.2.-) catalyzing the final step in Gl core structure biosynthesis. This study focuses on only one of the three SOTs that contribute to Gl biosynthesis. Homologues of AtSOT18 proteins were characterized, which was inspired by earlier findings on SOTs from ecotypes Col-0 and C24 differing in two amino acids (aa) and specific enzyme activities. Could there be a correlation of AtSOT18 enzyme activities and differences in Gl profiles between the ecotypes? SOT18 sequences from eight Arabidopsis ecotypes with highly diverse Gl patterns differed in two aa at various positions in the protein sequence. The SOT18 sequence from Col-0 showed the highest similarity to the largest number of other sequences in the alignment. The small differences in the primary sequence lead to important structural changes in secondary and tertiary structure that might be the key of different kinetic activities towards a broad range of substrates. All recombinant AtSOT18 proteins showed low substrate specificity with an indolic Gl, while the specificity for aliphatic substrates varied. There is no correlation in the kinetic behavior with the major ds-Gl contents or with the ratio of C-3/C-4 ds-Gl in the respective ecotype. Therefore, is it unlikely that ds-Gl AtSOT18 proteins play a major role in shaping the Gl profile in Arabidopsis
Views from within a narrative : Evaluating long-term human-robot interaction in a naturalistic environment using open-ended scenarios
Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. Date of acceptance: 16/06/2014This article describes the prototyping of human–robot interactions in the University of Hertfordshire (UH) Robot House. Twelve participants took part in a long-term study in which they interacted with robots in the UH Robot House once a week for a period of 10 weeks. A prototyping method using the narrative framing technique allowed participants to engage with the robots in episodic interactions that were framed using narrative to convey the impression of a continuous long-term interaction. The goal was to examine how participants responded to the scenarios and the robots as well as specific robot behaviours, such as agent migration and expressive behaviours. Evaluation of the robots and the scenarios were elicited using several measures, including the standardised System Usability Scale, an ad hoc Scenario Acceptance Scale, as well as single-item Likert scales, open-ended questionnaire items and a debriefing interview. Results suggest that participants felt that the use of this prototyping technique allowed them insight into the use of the robot, and that they accepted the use of the robot within the scenarioPeer reviewe
Distributed Symmetry Breaking in Hypergraphs
Fundamental local symmetry breaking problems such as Maximal Independent Set
(MIS) and coloring have been recognized as important by the community, and
studied extensively in (standard) graphs. In particular, fast (i.e.,
logarithmic run time) randomized algorithms are well-established for MIS and
-coloring in both the LOCAL and CONGEST distributed computing
models. On the other hand, comparatively much less is known on the complexity
of distributed symmetry breaking in {\em hypergraphs}. In particular, a key
question is whether a fast (randomized) algorithm for MIS exists for
hypergraphs.
In this paper, we study the distributed complexity of symmetry breaking in
hypergraphs by presenting distributed randomized algorithms for a variety of
fundamental problems under a natural distributed computing model for
hypergraphs. We first show that MIS in hypergraphs (of arbitrary dimension) can
be solved in rounds ( is the number of nodes of the
hypergraph) in the LOCAL model. We then present a key result of this paper ---
an -round hypergraph MIS algorithm in
the CONGEST model where is the maximum node degree of the hypergraph
and is any arbitrarily small constant.
To demonstrate the usefulness of hypergraph MIS, we present applications of
our hypergraph algorithm to solving problems in (standard) graphs. In
particular, the hypergraph MIS yields fast distributed algorithms for the {\em
balanced minimal dominating set} problem (left open in Harris et al. [ICALP
2013]) and the {\em minimal connected dominating set problem}. We also present
distributed algorithms for coloring, maximal matching, and maximal clique in
hypergraphs.Comment: Changes from the previous version: More references adde
Разработка SCADA системы гидравлического объекта с использованием программного комплекса WinCC
Выпускная квалификационная работа 00 страниц, 00 рисунков, 00 таблиц, 00 источников, 00 приложения.
Ключевые слова: программируемый контроллер Simatic S-400,гидравлический объект,программный пакет WinCC Explorer и Simatic Step7;
Цель работы — разработка SCADA системы гидравлического объекта с использованием программного комплекса WinCC.
Методы проведения работы: методы сбора,обработки и анализа информации, методы визуализации.
В ходе выполнения выпускной квалификационной работы были получены навыки работы с программно – логическим контроллером Siemens S7-400, программной средой Simatic Step7 и Simatic WinCC Explorer.
Результат выпускной квалификационной работы – разработка SCADA системы модернизированного гидравлического объекта с двумя контурами управления с использованием программного пакета WinCC.Выпускная квалификационная работа 00 страниц, 00 рисунков, 00 таблиц, 00 источников, 00 приложения.
Ключевые слова: программируемый контроллер Simatic S-400, гидравлический объект, программный пакет Проводник WinCC и Simatic Step7;
Цель работы - разработка SCADA системы гидравлического объекта с использованием программного комплекса WinCC.
Методы проведения работы: методы сбора, обработки и анализа информации, методы визуализации.
В ходе выполнения выпускной квалификационной работы были получены навыки работы с программно - логическим контроллером Siemens S7-400, программной средой Simatic Step7 и Simatic WinCC Explorer.
Результат выпускной квалификационной работы - разработка SCADA системы модернизированного гидравлического объекта с двумя контурами управления с использованием программного пакета WinCC
Sleep deprivation causes memory deficits by negatively impacting neuronal connectivity in hippocampal area CA1
Brief periods of sleep loss have long-lasting consequences such as impaired memory consolidation. Structural changes in synaptic connectivity have been proposed as a substrate of memory storage. Here, we examine the impact of brief periods of sleep deprivation on dendritic structure. In mice, we find that five hours of sleep deprivation decreases dendritic spine numbers selectively in hippocampal area CA1 and increased activity of the filamentous actin severing protein cofilin. Recovery sleep normalizes these structural alterations. Suppression of cofilin function prevents spine loss, deficits in hippocampal synaptic plasticity, and impairments in long-term memory caused by sleep deprivation. The elevated cofilin activity is caused by cAMP-degrading phosphodiesterase-4A5 (PDE4A5), which hampers cAMP-PKA-LIMK signaling. Attenuating PDE4A5 function prevents changes in cAMP-PKA-LIMK-cofilin signaling and cognitive deficits associated with sleep deprivation. Our work demonstrates the necessity of an intact cAMP-PDE4-PKA-LIMK-cofilin activation-signaling pathway for sleep deprivation-induced memory disruption and reduction in hippocampal spine density
Bipolaron Binding in Quantum Wires
A theory of bipolaron states in quantum wires with a parabolic potential well
is developed applying the Feynman variational principle. The basic parameters
of the bipolaron ground state (the binding energy, the number of phonons in the
bipolaron cloud, the effective mass, and the bipolaron radius) are studied as a
function of sizes of the potential well. Two cases are considered in detail: a
cylindrical quantum wire and a planar quantum wire. Analytical expressions for
the bipolaron parameters are obtained at large and small sizes of the quantum
well. It is shown that at [where means the radius (halfwidth) of a
cylindrical (planar) quantum wire, expressed in Feynman units], the influence
of confinement on the bipolaron binding energy is described by the function
for both cases, while at small sizes this influence is different
in each case. In quantum wires, the bipolaron binding energy increases
logarithmically with decreasing radius. The shapes and the sizes of a
nanostructure, which are favorable for observation of stable bipolaron states,
are determined.Comment: 17 pages, 6 figures, E-mail addresses: [email protected];
[email protected]
Rigidity percolation in a field
Rigidity Percolation with g degrees of freedom per site is analyzed on
randomly diluted Erdos-Renyi graphs with average connectivity gamma, in the
presence of a field h. In the (gamma,h) plane, the rigid and flexible phases
are separated by a line of first-order transitions whose location is determined
exactly. This line ends at a critical point with classical critical exponents.
Analytic expressions are given for the densities n_f of uncanceled degrees of
freedom and gamma_r of redundant bonds. Upon crossing the coexistence line, n_f
and gamma_r are continuous, although their first derivatives are discontinuous.
We extend, for the case of nonzero field, a recently proposed hypothesis,
namely that the density of uncanceled degrees of freedom is a ``free energy''
for Rigidity Percolation. Analytic expressions are obtained for the energy,
entropy, and specific heat. Some analogies with a liquid-vapor transition are
discussed. Particularizing to zero field, we find that the existence of a
(g+1)-core is a necessary condition for rigidity percolation with g degrees of
freedom. At the transition point gamma_c, Maxwell counting of degrees of
freedom is exact on the rigid cluster and on the (g+1)-rigid-core, i.e. the
average coordination of these subgraphs is exactly 2g, although gamma_r, the
average coordination of the whole system, is smaller than 2g. gamma_c is found
to converge to 2g for large g, i.e. in this limit Maxwell counting is exact
globally as well. This paper is dedicated to Dietrich Stauffer, on the occasion
of his 60th birthday.Comment: RevTeX4, psfig, 16 pages. Equation numbering corrected. Minor typos
correcte
Підвищення якості проведення аудиторних занять шляхом автоматизації методів контролю засвоєння матеріалу студентами
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