Search results for "DF"

showing 10 items of 1699 documents

H2 Transformations on Graphene Supported Palladium Cluster: DFT-MD Simulations and NEB Calculations

2020

Molecular dynamics simulations based on density functional theory were employed to investigate the fate of a hydrogen molecule shot with different kinetic energy toward a hydrogenated palladium cluster anchored on the vacant site of a defective graphene sheet. Hits resulting in H2 adsorption occur until the cluster is fully saturated. The influence of H content over Pd with respect to atomic hydrogen spillover onto graphene was investigated. Calculated energy barriers of ca. 1.6 eV for H-spillover suggest that the investigated Pd/graphene system is a good candidate for hydrogen storage.

Materials sciencespilloverhydrogen reactionchemistry.chemical_elementsupported metal catalysts02 engineering and technology010402 general chemistryKinetic energylcsh:Chemical technology01 natural sciencesDFTCatalysislaw.inventionlcsh:ChemistryMolecular dynamicsHydrogen storagelawCluster (physics)lcsh:TP1-1185Physical and Theoretical Chemistryhydrogenation elementary eventsGraphene021001 nanoscience & nanotechnology0104 chemical scienceschemistrylcsh:QD1-999Chemical physicsDensity functional theoryHydrogen spillover0210 nano-technologyPalladiumCatalysts
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The Influence of MSW Landfill Height in the Perched Leachate Formation

2012

During the last decades, the largest part of municipal solid waste (MSW) generated world wide has been disposed of in landfills without any pre-treatment. The main environmental impacts of such landfills, containing high amounts of biodegradable organic matter, are caused by emissions of liq-uid effluents and landfill gas. With no collection and treatment, leachates from landfills pollute groundwater and soils locally. Furthermore, besides the biological processes, many physical phe-nomena occur inside the landfill body which negatively affect landfill management. Indeed, the waste settlement inside the landfill body, with a consequent increase of its density, corresponds to a proportional …

Mathematical modelHydrologic balancesSettore ICAR/03 - Ingegneria Sanitaria-AmbientalePerched leachate zoneLandfill
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A fast heuristic for solving the D1EC coloring problem

2010

In this paper we propose an efficient heuristic for solving the Distance-1 Edge Coloring problem (D1EC) for the on-the-fly assignment of orthogonal wireless channels in wireless as soon as a topology change occurs. The coloring algorithm exploits the simulated annealing paradigm, i.e., a generalization of Monte Carlo methods for solving combinatorial problems. We show that the simulated annealing-based coloring converges fast to a sub optimal coloring scheme even for the case of dynamic channel allocation. However, a stateful implementation of the D1EC scheme is needed in order to speed-up the network coloring upon topology changes. In fact, a stateful D1EC reduces the algorithm’s convergen…

Mathematical optimization:QA Mathematics::QA75 Electronic computers. Computer science [Q Science]TheoryofComputation_COMPUTATIONBYABSTRACTDEVICESChannel allocation schemesHeuristic (computer science)Computer scienceSettore ING-INF/03 - Telecomunicazioni:T Technology (General) [T Technology]Topology (electrical circuits)Greedy coloringEdge coloringTheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGESStateful firewall:Q Science (General) [Q Science]TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYConvergence (routing)Simulated annealing:TK Electrical engineering. Electronics Nuclear engineering [T Technology]Channel assignment Edge coloring Simulated annealing.MathematicsofComputing_DISCRETEMATHEMATICS
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A challenging family of automata for classical minimization algorithms

2010

In this paper a particular family of deterministic automata that was built to reach the worst case complexity of Hopcroft's state minimization algorithm is considered. This family is also challenging for the two other classical minimization algorithms: it achieves the worst case for Moore's algorithm, as a consequence of a result by Berstel et al., and is of at least quadratic complexity for Brzozowski's solution, which is our main contribution. It therefore constitutes an interesting family, which can be useful to measure the efficiency of implementations of well-known or new minimization algorithms.

Mathematical optimizationComputer science[INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS][INFO.INFO-DS] Computer Science [cs]/Data Structures and Algorithms [cs.DS]0102 computer and information sciences02 engineering and technology01 natural sciencesMeasure (mathematics)Classical Minimization AlgorithmAutomatonRegular languageDFA minimization010201 computation theory & mathematics0202 electrical engineering electronic engineering information engineeringWorst-case complexity020201 artificial intelligence & image processingMinificationState (computer science)AlgorithmComputer Science::Formal Languages and Automata TheoryComputingMilieux_MISCELLANEOUS
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A holistic approach to design for 4D Printing

2019

Invented in 1983, as a rapid prototyping process, additive manufacturing (AM) is nowadays considered as a manufacturing process almost in the same way as conventional processes. For example, parts obtained by AM are found in aircraft structures. This AM evolution is mainly due to the shape complexity allowed by the process. The driving forces behind this evolution include: the development of various techniques on the layer-wise manufacturing principle and the improvement both in quantity and quality of the range of materials that can be processed. Many other AM techniques and materials continue to emerge. In the wake of the AM (usually referred to as 3D printing) another mode of manufacturi…

Matériaux intelligentsFabrication additiveConception pour l’impression 4DAdditive manufacturingDfamDesign for 4D Printing (Df4DP)Voxel-Based modelingSmart materials4D printingImpression 4D[PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph][PHYS.MECA.MEMA] Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph]Modélisation à base de voxelsConception pour la fabrication additive
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Sejas un žokļu traumas Paula Stradiņa Klīniskajā Universitātes slimnīcā

2020

Sejas un žokļu traumu ietekme uz hospitalizācijas ilgumu un neiroloģisko simptomātiku Paula Stradiņā Klīniskajā Universitātes slimnīcā. Viena no plašākajām traumu kategorijām, kas tieši pieder pie jebkuras valsts galvenajām sociālekonomiskajām problēmām un skar visus pasaules iedzīvotāju slāņus, un ir galvaskausa, sejas un apakšžokļu traumas. Sejas traumas ir bieži izplatītas, jo seja ir visatklātākā un neaizsargātākā ķermeņa daļa ar nelielu aizsargpārklājumu. Mutes dobuma un augšžokļa sejas traumas, papildus sejas estētikai, ietekmē tādas funkcijas kā elpošana, košļāšanas, rīšanas un runas funkcijas. Darba mērķi: noskaidrot FISS skalas ietekmi uz pareģojošo pacientu hospitalizācijas ilgumu…

Maxillofacial fracture; Midface fractures; Management of frontal sinus fractures; Surgical treatment at midface trauma; History of LeFort classification and study;Corelation betwen FISS and GCS scales;FISS scale and hospitalisation timeNOE fractures; FISS scale; GCS scale;MedicīnaSurgycal treatment of mandibular fracture; ORIF
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Curb your neuroticism – Mindfulness mediates the link between neuroticism and subjective well-being

2015

Abstract Recent research has shown that mindfulness moderates the negative emotional reactivity associated with neuroticism. In two studies, we investigated how neuroticism and mindfulness are associated with subjective well-being (SWB), assuming a moderated mediation. In Study 1, 147 participants (74.2% female, M  = 34.3 years, SD  = 11.9) completed an online survey. Mindfulness partially mediated but did not moderate the relationship between neuroticism and SWB, indicating that low levels of mindfulness were partially accountable for lower SWB in individuals high in neuroticism. In Study 2, 108 participants (80.6% female, M  = 25.2 years, SD  = 6.6) completed daily diaries for 6 days. We …

Mediation (statistics)MindfulnessModerated mediationmental disordersTraitNegative associationSubjective well-beingReactivity (psychology)PsychologyNeuroticismGeneral PsychologyClinical psychologyPersonality and Individual Differences
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Keep calm, pay attention, and carry on: Anxiety and consciousness mediate the effect of, mindfulness on driving performance in young drivers

2021

Abstract Road traffic crashes are currently one of the main causes of deaths in the world and many efforts have been made to develop effective interventions to reduce them. Mindfulness has risen as a method for improving mental and physical well-being and has been hypothesized as potentially beneficial for driving performance. This has led to some commercial ventures based on such hypothesis, despite that the empirical evidence backing up them is still limited. Besides, at the moment there is not yet a clear account of the specific mechanism underlying this proposals. So, it seems plausible that the relationship between mindfulness and driving performance is indirect, and that personality t…

Mediation (statistics)Mindfulnessmedia_common.quotation_subjectApplied psychologyDriving simulatorTransportationConscientiousnessNeuroticismAutomotive EngineeringmedicineAnxietyPersonalitymedicine.symptomBig Five personality traitsPsychologyApplied PsychologyCivil and Structural Engineeringmedia_commonTransportation Research Part F: Traffic Psychology and Behaviour
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2019

IntroductionTeachers and student teachers in Germany are a high-risk population for stress and stress-related mental health problems. This often leads to early retirement in subsequent professional life. Various trials have demonstrated positive effects of stress prevention training on the perceived stress and stress-related symptoms of teachers. Although many studies show positive effects of mindfulness-based stress interventions, there is not yet any mindfulness-based intervention for teachers or student teachers in Germany. The aim of this trial is to evaluate a training that combines mindfulness-based and cognitive interventions into one programme, addressing to the specific burdens of …

Medical educationeducation.field_of_studyMindfulnessDescriptive statisticsbusiness.industryeducation05 social sciencesPopulationPsychological intervention050301 educationRepeated measures designGeneral MedicineBurnout030210 environmental & occupational healthMental healthlaw.invention03 medical and health sciences0302 clinical medicineRandomized controlled triallawMedicinebusinesseducation0503 educationBMJ Open
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Teknologian rooli meditaatioharjoittelussa

2016

Informaatioteknologian kehitys on mahdollistanut meditaatioharjoitteiden tehokkaan leviämisen länsimaisten kulttuurien ulottuville. Digitaalisissa ympäristöissä informaatio leviää erittäin tehokkaasti ja meditaatioharjoitteisiin liittyvään informaatioon törmääminen onkin todennäköisempää kuin koskaan aikaisemmin. Meditoinnin ollaan havaittu edistävän hyvinvointia useilla elämän osa-alueilla ja tuloksien käytännönläheinen soveltaminen edistyy jatkuvasti. Vuosien saatossa informaatioteknologiaa on kehitetty lukuisiin asiayhteyksiin, eikä meditaatioharjoittelu ole jäänyt teknologisen kehityskulun ulkopuolelle. Markkinoilla liikkuu lukuisia erilaisia meditaatioharjoittelua tukevia sovelluksia, …

MeditaatiomindfulnesshyvinvointiteknologiainternetstressiEEGälypuhelinmobiilivirtuaalitodellisuus
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