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Suche nach „[2017]“ hat 109 Publikationen gefunden
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    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Teisnach Sensorik

    Zeitschriftenartikel

    F. Singer, Maria Kufner

    Model based laser-ultrasound determination of hardness gradients of gas-carburized steel

    NDT & E International, vol. 88, pp. 24-32

    2017

    DOI: 10.1016/j.ndteint.2017.02.006

    Abstract anzeigen

    Gas carburizing is a common industrial process utilized for case hardening of low carbon steels. However, thereis a lack of non-destructive evaluation systems for the measurement of hardness-depth profiles. We propose anovel measurement method for the determination of hardness-depth profiles of two-step gas carburized steelspecimens. The method is based on the measurement of broadband laser excited Rayleigh waves. Rayleighwaves were generated by a pulsed Nd: YAG laser in the thermoelastic regime and measured with a heterodyneMach-Zehnder interferometer in the near-field. From two measurements with different source to receiverdistances the dispersion diagrams were calculated by means of the phase spectral analysis method. In order tosimulate the observed dispersive behavior of the Rayleigh waves,first the two-step gas carburizing process wassimulated using solutions of the diffusion equation. The resulting continuous hardness profile was thendiscretized into up to 100 layers. Thereafter the Rayleigh wave dispersion diagram was calculated from thediscretized stack of layers using a delta-matrix formulation of the Thomson-Haskell transfer matrix method. Inorder to obtain bestfitting hardness profiles, the simulated dispersion diagrams werefitted to measurementswith a curvefitting algorithm. Comparison of the Rayleigh wave inversion method with destructively obtainedVickers hardness profiles shows good quantitative agreement.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Damigos, Y., Tsaoussidis, V., Frankenstein, B., Brady, K., Lenas, S.-A., Loupos, K., Gerhard, R., Schulze, M., Amditis, A., Malliou, C.M., Wirges, W., Dmitry Rychkov, Chatziandreoglou, C.

    Structural health monitoring system for bridges based on skin-like sensor

    IOP Conference Series: Materials Science and Engineering, vol. 236, no. Proceedings of BESTInfra2017 - Building up Efficient and Sustainable TransportInfrastructure 2017

    2017

    DOI: 10.1088/1757-899X/236/1/012100

    Abstract anzeigen

    Structural health monitoring activities are of primal importance for managing transport infrastructure, however most SHM methodologies are based on point-based sensors that have limitations in terms of their spatial positioning requirements, cost of development and measurement range. This paper describes the progress on the SENSKIN EC project whose objective is to develop a dielectric-elastomer and micro-electronics-based sensor, formed from a large highly extensible capacitance sensing membrane supported by advanced microelectronic circuitry, for monitoring transport infrastructure bridges. Such a sensor could provide spatial measurements of strain in excess of 10%. The actual sensor along with the data acquisition module, the communication module and power electronics are all integrated into a compact unit, the SENSKIN device, which is energy-efficient, requires simple signal processing and it is easy to install over various surface types. In terms of communication, SENSKIN devices interact with each other to form the SENSKIN system; a fully distributed and autonomous wireless sensor network that is able to self-monitor. SENSKIN system utilizes Delay-/Disruption-Tolerant Networking technologies to ensure that the strain measurements will be received by the base station even under extreme conditions where normal communications are disrupted. This paper describes the architecture of the SENSKIN system and the development and testing of the first SENSKIN prototype sensor, the data acquisition system, and the communication system.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTC Weißenburg

    Zeitschriftenartikel

    Gerhard, R., Dmitry Rychkov, Wang, J.

    Chemical modification with orthophosphoric acid enhances surface-charge stability on polypropylene electrets

    Applied Physics Letters, vol. 110, no. 19

    2017

    DOI: 10.1063/1.4983348

    Abstract anzeigen

    The low surface-charge stability of polypropylene (PP) frequently limits its application as an electret material. In this paper, we demonstrate how the treatment of PP-film surfaces with orthophosphoric acid (H3PO4) enhances their charge stability. To discriminate between the effects of chemical modification and thermal treatment, as-received and annealed PP films are used as reference samples. The electret properties of treated and non-treated PP films are characterized with thermally stimulated discharge (TSD) and isothermal surface-potential decay (ISPD) experiments, from which considerable improvement in thermal and temporal charge stability is observed for samples modified with H3PO4. The half-value temperature (T1∕2) observed on TSD curves of chemically treated PP increases to 131 and 145 °C for positive and negative charges, respectively. The enhancement might be attributed to the phosphoric compounds detected on the H3PO4-modified surfaces via attenuated-total-reflection infrared spectroscopy. Deeper surface traps formed at the “foreign” phosphorus-containing structures are able to capture the charges over longer time periods and at higher temperatures, thus leading to significant improvements in the temporal and thermal surface-charge stabilities of PP electrets.

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Ermitteln der Remanenz eines Kraftstoffinjektors [EN] Determination of the remanence of a fuel injector [FR] Détermination de rémanence d'un injecteur de carburant

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Ansteuerung von Kraftstoffinjektoren bei variierender Bordnetzspannung [EN] Actuation of fuel injectors in the event of varying vehicle electrical system voltag [FR] Commande d'injecteurs de ...

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Method and device for adapting the opening behaviour of a fuel injector

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Method and device for adapting the opening behaviour of a fuel injector

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Determination of a point in time of a predetermined open state of a fuel injector

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk, U. Wagner

    [DE] Verfahren und Vorrichtung zum Anpassen des Öffnungsverhaltens eines Kraftstoffinjektors [EN] Method and device for adapting the opening behaviour of a fuel injector [FR] Procédé et dispositif ...

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Rösel G., Frank Denk

    [DE] Verfahren zum Betreiben eines Kraftstoffinjektors mit Leerhub [EN] Method for operating a fuel injector with an idle stroke [FR] Procédé permettant de faire fonctionner un injecteur de carburant ...

    2017

    TC Cham

    Patent

    Stutika M., Continental Automotive GmbH, N. Belyaev, Frank Denk, A. Lyubar, G. Roesel, C. Hauser

    Method and device for detecting the commencement of opening of a nozzle needle

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, N. Belyaev, M. Stutika, G. Rösel, Frank Denk, A. Lyubar, C. Hauser

    Method and device for detecting commencement of opening of nozzle needle

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Verfahren zum Betreiben eines Kraftstoffinjektors mit Leerhub [EN] Method for operating a fuel injector with an idle stroke [FR] Procédé de fonctionnement d'un injecteur de fonctionnement d'un injecteur de carburant à course ...

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Bestimmung des elektrischen Widerstands eines Kraftstoffinjektors mit Magnetspulenantrieb

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk, U. Wagner

    Verfahren und Vorrichtung zum Anpassen des Öffnungsverhaltens eines Kraftstoffinjektors

    2017

    TC Cham

    Patent

    Frank Denk

    Verfahren zum Betreiben eines Kraftstoffinjektors mit Leerhub

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    [DE] Präzise Bestimmung des elektrischen Widerstands eines Kraftstoffinjektors mit Magnetspulenanstrieb [EN] Precise determination of the electrical resistance of a fuel injector having a solenoid drive ...

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Ansteuerung von Kraftstoffinjektoren bei variierender Bordnetzspannung

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Ermitteln der Remanenz eines Kraftstoffinjektors

    2017

    TC Cham

    Patent

    Continental Automotive GmbH, Frank Denk

    Device and Method for Controlling an Injection Valve

    2017