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Design of Passive Dynamic Walking Robots for Additive Manufacture
Ongoing research in the direction of printable, non-assembly mechatronic systems give
rise to the need for multi-material printing, including electronics. However, there are robotic
systems that do not use electronic components and still exhibit complex dynamic behavior. Such
passive dynamic systems have the potential to save energy and component cost in the field of
robotics compared to actuated systems. Ongoing research in computational design synthesis of
passive dynamic systems aims at automatically generating robotic configurations based on a
given task. However, an automated design-to-fabrication process also requires a flexible
fabrication method. Towards the goal of printing functional, non-assembly passive dynamic
robots using Fused Deposition Modeling (FDM), this paper explores designing and fabricating
passive walking robots and all necessary components using single material FDM. Two
configurations of passive dynamic walkers are re-designed and fabricated in this paper. For one
of them all components are printed in one job and only little assembly after printing is needed.
However, the gait cycle of the second configuration is much more sensitive to small parametric
changes and therefore more flexible prototyping is needed in order to allow adjusting of the robot
after printing. Moreover, FDM printed robotic joints with sufficient smoothness and axial
stiffness are required and a variety of different joint assemblies are designed and tested for the
robot prototypes. Even though the most stable gait for the second robot is achieved using a metal
bearing instead of the FDM printed ones, this is not necessary for the first robot example. The
approach to prototyping with FDM presented in this paper allows achieving functionality through
design iteration without incurring significant cost. To arrive at feasible solutions, a modular
design approach allows to combine different joints, legs, feet and balancing weights and the
connection points of the different elements are adjustable after printing, which makes it possible
to shift the center of gravity and other variables of the robot.Mechanical Engineerin
Kann die 18F-FDG-PET/CT-Untersuchung die Panendoskopie zur Detektion von synchronen Zweitkarzinomen ersetzen?
Ziel der Arbeit war es, die Wertigkeit der 18F-FDG-PET/
CT-Untersuchung bezüglich synchroner Zweitkarzinome im Vergleich mit der Panendoskopie beim initialen Staging zu untersuchen. 311 Patienten wurden mit beiden Untersuchungsmethoden abgeklärt. Als Referenz galt die zytologische, histologische und/oder klinische oder radiologische Untersuchung. Die Prävalenz für synchrone Zweitkarzinome betrug mit der Panendoskopie 4,5%, während die Prävalenz mittels PET/ CT-Untersuchung 6,1% betrug. Die Sensitivität für die Panendoskopie betrug 74%, die Spezifität 99,7%, der positiv prädiktive Wert 93% und der negativ prädiktive Wert 98%. Die Sensitivität für die PET/CT-Untersuchung betrug 100%, die Spezifität 95,7% der positiv prädiktive Wert 59% und der negativ prädiktive Wert
100%. Die PET/CT-Untersuchung scheint der Panendoskopie
überlegen zu sein. Bei bezüglich synchroner Zweitkarzinome unauffälligem PET/CT kann die Panendoskopie auf die Endoskopie und Beurteilung des Primärtumors beschränkt werden kann. Aufgrund der hohen Kosten und der grossen Anzahl falsch positiver Resultate, welche durch das PET/CT generiert werden, empfehlen wir die Durchführung dieser Untersuchung nur bei fortgeschrittenen Tumoren mit der Frage nach Fernmetastasen. Die Panendoskopie bleibt weiterhin der Goldstandar
Combining Monte Carlo generators with next-to-next-to-leading order calculations: event reweighting for Higgs boson production at the LHC
We study a phenomenological ansatz for merging next-to-next-to-leading order
(NNLO) calculations with Monte Carlo event generators. We reweight them to
match bin-integrated NNLO differential distributions. To test this procedure,
we study the Higgs boson production cross-section at the LHC, for which a fully
differential partonic NNLO calculation is available. We normalize PYTHIA and
MC@NLO Monte Carlo events for Higgs production in the gluon fusion channel to
reproduce the bin integrated NNLO double differential distribution in the
transverse momentum and rapidity of the Higgs boson. These events are used to
compute differential distributions for the photons in the pp \to H \to \gamma
\gamma decay channel, and are compared to predictions from fixed-order
perturbation theory at NNLO. We find agreement between the reweighted
generators and the NNLO result in kinematic regions where we expect a good
description using fixed-order perturbation theory. Kinematic boundaries where
resummation is required are also modeled correctly using this procedure. We
then use these events to compute distributions in the pp \to H \to W^+W^- \to
l^+l^- \nu\bar{\nu} channel, for which an accurate description is needed for
measurements at the LHC. We find that the final state lepton distributions
obtained from PYTHIA are not significantly changed by the reweighting
procedure.Comment: 18 pages, 14 fig
NNLO QCD predictions for the H -> WW -> l l nu nu signal at the LHC
We present a first computation of the NNLO QCD cross section at the LHC for
the production of four leptons from a Higgs boson decaying into W bosons. We
study the cross section for a Higgs boson mass Mh = 165 GeV; around this value
a Standard Model Higgs boson decays almost exclusively into W-pairs. We apply
all nominal experimental cuts on the final state leptons and the associated jet
activity and study the magnitude of higher-order effects up to NNLO on all
kinematic variables which are constrained by experimental cuts. We find that
the magnitude of the higher-order corrections varies significantly with the
signal selection cuts. As a main result we give the value of the cross section
at NNLO with all selection cuts envisaged for the search for the Higgs boson.Comment: typos corrected, version accepted in JHE
Social corrections act as a double-edged sword by reducing the perceived accuracy of false and real news in the UK, Germany, and Italy
This is the final version. Available from Nature Research via the DOI in this record. Data availability:
All shareable data are found on the online OSF repository at https://osf.io/jhwfgCode availability:
All the code including reproducible analyses are found on the online OSF repository at
https://osf.io/4hjcf for data relating to the UK, https://osf.io/yvdj4 for Italy, and https://
osf.io/jhwfg Germany.Corrective or refutational posts from ordinary users on social media have the potential to improve the online information ecosystem. While initial evidence of these social corrections is promising, a better understanding of the effects across different topics, formats, and audiences is needed. In three pre-registered experiments (N = 1944 UK, N = 2467 Italy, N = 2210 Germany) where respondents completed a social media post assessment task with false and true news posts on various topics (e.g., health, climate change, technology), we find that social corrections reduce perceived accuracy of and engagement with false news posts. We also find that social corrections that flag true news as false decrease perceived accuracy of and engagement with true news posts. We did not find evidence to support moderation of these effects by correction strength, anti-expert sentiments, cognitive reflection capacities, or susceptibility to social influence. While social corrections can be effective for false news, they may also undermine belief in true news.British AcademyDavidson Colleg
ifo Konjunkturprognose 2017/2018: Deutsche Wirtschaft stark und stabil
Der Aufschwung, in dem sich die deutsche Wirtschaft seit nunmehr 2013 befindet, gewinnt an Stärke und Breite. Das ifo Institut rechnet mit einem Zuwachs des realen Bruttoinlandsprodukts von 1,8% im laufenden und 2,0% im kommenden Jahr. Wie schon in den vergangenen Jahren wird die konjunkturelle Entwicklung von der weiter lebhaften Konsumnachfrage der privaten Haushalte und der regen Bautätigkeit bestimmt. Einen zunehmenden Beitrag zum Aufschwung werden die Exporte leisten
Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter
This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPEnsuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered
Predictors of enhancing human physical attractiveness: Data from 93 countries
People across the world and throughout history have gone to great lengths to enhance their physical appearance. Evolutionary psychologists and ethologists have largely attempted to explain this phenomenon via mating preferences and strategies. Here, we test one of the most popular evolutionary hypotheses for beauty-enhancing behaviors, drawn from mating market and parasite stress perspectives, in a large cross-cultural sample. We also test hypotheses drawn from other influential and non-mutually exclusive theoretical frameworks, from biosocial role theory to a cultural media perspective. Survey data from 93,158 human participants across 93 countries provide evidence that behaviors such as applying makeup or using other cosmetics, hair grooming, clothing style, caring for body hygiene, and exercising or following a specific diet for the specific purpose of improving one physical attractiveness, are universal. Indeed, 99% of participants reported spending >10 min a day performing beauty-enhancing behaviors. The results largely support evolutionary hypotheses: more time was spent enhancing beauty by women (almost 4 h a day, on average) than by men (3.6 h a day), by the youngest participants (and contrary to predictions, also the oldest), by those with a relatively more severe history of infectious diseases, and by participants currently dating compared to those in established relationships. The strongest predictor of attractiveness-enhancing behaviors was social media usage. Other predictors, in order of effect size, included adhering to traditional gender roles, residing in countries with less gender equality, considering oneself as highly attractive or, conversely, highly unattractive, TV watching time, higher socioeconomic status, right-wing political beliefs, a lower level of education, and personal individualistic attitudes. This study provides novel insight into universal beauty-enhancing behaviors by unifying evolutionary theory with several other complementary perspectives.info:eu-repo/semantics/publishedVersio
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