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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Temperature-Compensated Force/Pressure Sensor Based on Multi-Walled Carbon Nanotube Epoxy Composites

Dinh, Nghia Trong, Kanoun, Olfa 10 November 2015 (has links) (PDF)
In this study, we propose a multi-walled carbon nanotube epoxy composite sensor for force and pressure sensing in the range of 50 N–2 kN. A manufacturing procedure, including material preparation and deposition techniques, is proposed. The electrode dimensions and the layer thickness were optimized by the finite element method. Temperature compensation is realized by four nanocomposites elements, where only two elements are exposed to the measurand. In order to investigate the influence of the filler contents, samples with different compositions were prepared and investigated. Additionally, the specimens are characterized by cyclical and stepped force/pressure loads or at defined temperatures. The results show that the choice of the filler content should meet a compromise between sensitivity, temperature influence and noise behavior. At constant temperature, a force of at least 50N can be resolved. The measurement error due to the temperature influence is 150N in a temperature range of –20°C–50°C.
272

Advanced Joining Technologies for Load and Fibre Adjusted FRP-Metal Hybrid Structures

Klein, Mario, Podlesak , Frank, Höfer, Kevin, Seidlitz, Holger, Gerstenberger, Colin, Mayr, Peter, Kroll, Lothar 27 August 2015 (has links) (PDF)
Multi-material-design (MMD) is commonly realized through the combination of thin sheet metal and fibre reinforced plastics (FRP). To maximize the high lightweight potential of the material groups within a multi-material system as good as possible, a material-adapted and particularly fibre adjusted joining technology must be applied. The present paper focuses on two novel joining technologies, the Flow Drill Joining (FDJ) method and Spin-Blind-Riveting (SBR), which were developed for joining heavy-duty metal/composite hybrids. Tests were carried out with material combinations which are significant for lightweight constructions such as aluminium (AA5083) and carbon fibre-reinforced polyamide in sheet thickness of 1.8 mm. The mechanical testing and manufacturing of those multi-material joints was investigated.
273

Causes and Consequences of Schadenfreude and Sympathy: A Developmental Analysis

Schindler, Rose, Körner, André, Bauer, Sylvia, Hadji, Sarina, Rudolph, Udo 11 November 2015 (has links) (PDF)
Moral judgments and moral emotions are a ubiquitous feature of social interactions. Humans decide quickly and intuitively whether an action is morally right or wrong. Schadenfreude and sympathy, as emotional reactions to the misfortunes of others, are prototypical moral emotions. So far, however, little evidence exists concerning children’s understanding of schadenfreude. Within three studies, we investigated the experience of schadenfreude and sympathy among N = 364 children of different age groups. We interviewed the children while showing them picture stories. In the picture stories, we varied the behavior of the protagonist prior to a misfortune: (1) whether his behavior had been morally right or wrong, (2) whether the protagonist attained his goal, (3) whether the protagonist was responsible for the misfortune. In addition, in one study we varied (4) the emotional relationship of the interviewed children to the protagonist. Furthermore, we asked the children to decide whether they want to sit next to the protagonist or do him a favor. Results show that children experience sympathy as well as schadenfreude at the age of 4 years. Sympathy is more likely to arise when the protagonists of a story are likable, when these actors typically pursue morally positive goals, and if they are not responsible for their misfortune. In contrast, schadenfreude is more likely when the protagonist is disliked, when actors pursue immoral goals and if they are responsible for their misfortune. In addition, sympathy increases approach (helping behavior, sitting next to the agent and doing favors), whereas schadenfreude increases avoidance tendencies.
274

ANNarchy: a code generation approach to neural simulations on parallel hardware

Vitay, Julien, Dinkelbach, Helge Ülo, Hamker, Fred Henrik 07 October 2015 (has links) (PDF)
Many modern neural simulators focus on the simulation of networks of spiking neurons on parallel hardware. Another important framework in computational neuroscience, rate-coded neural networks, is mostly difficult or impossible to implement using these simulators. We present here the ANNarchy (Artificial Neural Networks architect) neural simulator, which allows to easily define and simulate rate-coded and spiking networks, as well as combinations of both. The interface in Python has been designed to be close to the PyNN interface, while the definition of neuron and synapse models can be specified using an equation-oriented mathematical description similar to the Brian neural simulator. This information is used to generate C++ code that will efficiently perform the simulation on the chosen parallel hardware (multi-core system or graphical processing unit). Several numerical methods are available to transform ordinary differential equations into an efficient C++code. We compare the parallel performance of the simulator to existing solutions.
275

Local Dynamic Map als modulares Software Framework für Fahrerassistenzsysteme

Reisdorf, P., Auerswald, A., Wanielik, G. 13 November 2015 (has links) (PDF)
Moderne Fahrerassistenzsysteme basieren auf der Verarbeitung von Informationen, welche durch die Umfeldwahrnehmung mit unterschiedlicher Sensorik erfolgt. Neben den Informationen aus dem eigenen Fahrzeug ergeben sich durch unterschiedliche Kommunikationsmöglichkeiten (Car2Car, Car2X, ...) erweiterte Umfeldwahrnehmungen (siehe Abb. 1). Diese Daten gilt es aufbereitet und zielorientiert einer Anwendung zur Verfügung zu stellen, was mit Hilfe einer Local Dynamic Map (LDM) erfüllt werden kann. Die vorliegende Veröffentlichung beschreibt den Aufbau, Verwendungszweck und Eigenschaften einer entwickelten LDM und geht auf einige Applikationen ein, die mit Hilfe dieser realisiert wurden.
276

Future Cognitive Ability: US IQ Prediction until 2060 Based on NAEP

Rindermann, Heiner, Pichelmann, Stefan 26 November 2015 (has links) (PDF)
The US National Assessment of Educational Progress (NAEP) measures cognitive competences in reading and mathematics of US students (last 2012 survey N = 50,000). The long-term development based on results from 1971 to 2012 allows a prediction of future cognitive trends. For predicting US averages also demographic trends have to be considered. The largest groups’ (White) average of 1978/80 was set at M = 100 and SD = 15 and was used as a benchmark. Based on two past NAEP development periods for 17-year-old students, 1978/80 to 2012 (more optimistic) and 1992 to 2012 (more pessimistic), and demographic projections from the US Census Bureau, cognitive trends until 2060 for the entire age cohort and ethnic groups were estimated. Estimated population averages for 2060 are 103 (optimistic) or 102 (pessimistic). The average rise per decade is dec = 0.76 or 0.45 IQ points. White-Black and White-Hispanic gaps are declining by half, Asian-White gaps treble. The catch-up of minorities (their faster ability growth) contributes around 2 IQ to the general rise of 3 IQ; however, their larger demographic increase reduces the general rise at about the similar amount (-1.4 IQ). Because minorities with faster ability growth also rise in their population proportion the interactive term is positive (around 1 IQ). Consequences for economic and societal development are discussed.
277

Inkjet Printing of Colloidal Nanospheres

Sowade, Enrico, Blaudeck, Thomas, Baumann, Reinhard R. 12 November 2015 (has links) (PDF)
We report on inkjet printing of aqueous colloidal suspensions containing monodisperse silica and/or polystyrene nanosphere particles and a systematic study of the morphology of the deposits as a function of different parameters during inkjet printing and solvent evaporation. The colloidal suspensions act as a model ink for an understanding of layer formation processes and resulting morphologies in inkjet printing in general. We investigated the influence of the surface energy and the temperature of the substrate, the formulation of the suspensions, and the multi-pass printing aiming for layer stacks on the morphology of the deposits. We explain our findings with models of evaporation-driven self-assembly of the nanosphere particles in a liquid droplet and derive methods to direct the self-assembly processes into distinct one- and two-dimensional deposit morphologies.
278

Crystal structure of 3-ferrocenyl-1-phenyl-1H-pyrrole, [Fe(η5-C5H4cC4H3NPh)(η5-C5H5)]

Pfaff, Ulrike, Korb, Marcus, Lang, Heinrich 13 May 2016 (has links) (PDF)
The molecular structure of the title compound, [Fe(C 5 H 5 )(C 15 H 12 N)], consists of a ferrocene moiety with an N-phenylpyrrole heterocycle bound to one cyclopentadienyl ring. The 1,3-disubstitution of the pyrrole results in an L- shaped arrangement of the molecule with plane intersections of 2.78 (17)° between the pyrrole and the N-bonded phenyl ring and of 8.17 (18)° between the pyrrole and the cyclopentadienyl ring. In the crystal, no remarkable intermolecular interactions are observed.
279

Electromechanical Behavior of Chemically Reduced Graphene Oxide and Multi-walled Carbon Nanotube Hybrid Material

Benchirouf, Abderrahmane, Müller, Christian, Kanoun, Olfa 14 May 2016 (has links) (PDF)
In this paper, we propose strain-sensitive thin films based on chemically reduced graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) without adding any further surfactants. In spite of the insulating properties of the thin-film-based GO due to the presence functional groups such as hydroxyl, epoxy, and carbonyl groups in its atomic structure, a significant enhancement of the film conductivity was reached by chemical reduction with hydro-iodic acid. By optimizing the MWCNT content, a significant improvement of electrical and mechanical thin film sensitivity is realized. The optical properties and the morphology of the prepared thin films were studied using ultraviolet-visible spectroscopy (UV-Vis) and scanning electron microscope (SEM). The UV-Vis spectra showed the ability to tune the band gap of the GO by changing the MWCNT content, whereas the SEM indicated that the MWCNTs were well dissolved and coated by the GO. Investigations of the piezoresistive properties of the hybrid nanocomposite material under mechanical load show a linear trend between the electrical resistance and the applied strain. A relatively high gauge factor of 8.5 is reached compared to the commercial metallic strain gauges. The self-assembled hybrid films exhibit outstanding properties in electric conductivity, mechanical strength, and strain sensitivity, which provide a high potential for use in strain-sensing applications.
280

How Do Theories of Cognition and Consciousness in Ancient Indian Thought Systems Relate to Current Western Theorizing and Research?

Sedlmeier, Peter, Srinivas, Kunchapudi 17 August 2016 (has links) (PDF)
Unknown to most Western psychologists, ancient Indian scriptures contain very rich, empirically derived psychological theories that are, however, intertwined with religious and philosophical content. This article represents our attempt to extract the psychological theory of cognition and consciousness from a prominent ancient Indian thought system: Samkhya-Yoga. We derive rather broad hypotheses from this approach that may complement and extend Western mainstream theorizing. These hypotheses address an ancient personality theory, the effects of practicing the applied part of Samkhya-Yoga on normal and extraordinary cognition, as well as different ways of perceiving reality. We summarize empirical evidence collected (mostly without reference to the Indian thought system) in diverse fields of research that allows for making judgments about the hypotheses, and suggest more specific hypotheses to be examined in future research. We conclude that the existing evidence for the (broad) hypotheses is substantial but that there are still considerable gaps in theory and research to be filled. Theories of cognition contained in the ancient Indian systems have the potential to modify and complement existing Western mainstream accounts of cognition. In particular, they might serve as a basis for arriving at more comprehensive theories for several research areas that, so far, lack strong theoretical grounding, such as meditation research or research on aspects of consciousness.

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