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Le concept d’économie circulaire permet d’aborder dans un même référentiel les questions énergétiques et patrimoniales. Forts de cette nouvelle perspective, une spécialiste en politiques publiques de la durabilité et économie circulaire et un architecte du patrimoine plaident pour traiter les enjeux liés aux deux domaines ensemble, dans une même loi.

Rotary mechanisms are commonly used for transferring rotational movement in diverse industrial applications in mechanical engineering. Components such as gears and rolling bearings have found their purpose in various automotive, machinery or agriculture systems. During operation in mechanisms, they are subjected to defects or changes of their key parameters. This paper considers the application of recurrence plots (RP) and recurrence quantification analysis (RQA) in the detection of teeth crack in a planetary gear system and radial internal clearance (RIC) in a double row self-aligning ball bearing. Raw signals are obtained from accelerometers installed in test rigs. The analysis consists of a statistical analysis approach and calculations of basic RQA parameters i.e. recurrence rate, determinism and length of the longest diagonal. In the paper, we extract information about the fault detection in one of the rotary systems and about bearing operational parameters with nonlinear dynamics identification.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019; Aachen 1 Online-Ressource (xii, 187 Seiten) : Illustrationen (2019). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019, In my dissertation I am investigating vaccination behavior theoretically and experimentally from a microeconomic perspective. This dissertation applies a game-theoretical vaccination model (I-Vax game), which considers the direct and indirect effects of vaccination and examines the incentives of a vaccination decision. This model is used for controlled economic laboratory and online experiments to empirically investigate research questions on vaccination behavior. The four chapters of this dissertation each represent one research project. In all projects, I use the I-Vax game as an experimental tool, either as an online or a laboratory experiment, to shed light on and understand vaccination behavior and decisions from different perspectives. The experimental designs of the studies in Chapters 1 and 2 are intended to investigate and understand the behavioral consequences of different policy measures on vaccination decisions. In Chapter 1, it is examined to what extent non-obligatory vaccination recommendations made by health authorities for different risk groups can influence vaccination behavior. Chapter 2 deals with the questions how individual preferences for mandatory and voluntary vaccination policies emerge before and after participants experience these vaccination policies and how individual preferences for these policies change over time. Chapter 3 examines psychological factors that can influence vaccination behavior. I investigate to what extent the responsibility of non-vaccinated individuals in the population influences the vaccination behavior of others who still have to make a vaccination decision. I distinguish between low responsibility individuals, who would like to be vaccinated but cannot, and high responsibility individuals, who do not want to be vaccinated but actually can be. In both contexts, there is the same incentive structure from an economic perspective. Only the perception of the responsibility of the unvaccinated individuals in this project influences vaccination behavior. Chapter 4 deals with economic incentives. If the effectiveness of a vaccine is low, the incentive to be vaccinated increases from an individual rational perspective. I examine whether individuals understand this relationship and whether they behave rationally given the economic incentive structure. All four projects have in common that they analyze factors that influence either vaccination behavior or acceptance (preferences) of vaccination policies., Published by Aachen

Im Rahmen dieser Dissertation wurde eine Messvorrichtung entwickelt, die es ermöglicht, die radiale Lagerluft verschiedener Lagertypen und Lagergrößen präzise vor, während und nach der Montage eines Wälzlagers auf der Welle zu messen und gleichzeitig die Daten im Zeitalter von Industrie 4.0 weiterzuverarbeiten. In der modernen Technik nehmen Wälzlager als Bindeglied zwischen stillstehenden und bewegten Teilen in Maschinen, Fahrzeugen, Anlagen und Geräten eine bedeutende Rolle ein. Häufig fallen Wälzlager allerdings vor dem Erreichen ihrer berechneten Lebensdauer aus, was unter anderem auf Fehler während der Montage zurückzuführen ist.In der Regel werden Wälzlager mit einer bestimmten „Lagerluft“ eingebaut. Unter Lagerluft versteht man das Maß, um das sich ein Lagerring gegenüber dem anderen in radialer Richtung (Radialluft) oder in axialer Richtung (Axialluft) von einer Grenzstellung in die andere verschieben lässt.Für den einwandfreien Lauf eines Lagers ist die Radialluft von entscheidender Bedeutung. Richtig eingestellte Wälzlager führen zu einer längeren Standzeit und verursachen weniger Energieverluste.Durch die neuentwickelte Messvorrichtung können Montagefehler verhindert und die Qualität der montierten Lagereinheiten gesteigert werden. Außerdem werden die Selbstwartung und die Integration des Lagers in einem Internet der Dinge sowie der Übergang zu einer digitalisierten Umgebung ermöglicht.

Most of the bearing positions are designed with rolling bearings. Usually rolling bearings are manufactured with a cer-tain “bearing clearance”. Bearing clearance is defined as the total distance through which one bearing ring can be moved relative to the other in the radial direction (radial clearance) or in the axial direction (axial clearance). The radial clearance of a bearing is of considerable importance if reliable operation expected. Correctly installed rolling bearings increase the lifetime and cause less energy loss. In case of radial rolling bearings with a tapered bore, which are fas-tened on the shaft with an adapter sleeve, the radial clearance is reduced during the process of mounting.There are known measuring devices, that allow to check the radial clearance fully automatically in the uninstalled state. Methods for checking the radial clearance in the installed state are known as well. The simplest method is the use of feeler gauges. Even simple measuring devices are known where the bearing is turned by hand and the radial clearance is read manually via a dial gauge. The measurements of these methods are sometimes subject to large fluctuations because each assembly operator is not performing the task exactly the same – human variation.The intent of this work is to develop a method for measuring radial clearance during the assembly process. The meas-urement result should be reproducible and not influenced by the assembly operator’s natural variation while performing the task. For this reason, a measuring device was developed. The radial clearance can now be measured before, during and immediately after the process of mounting bearings with tapered bore which are fastened on the shaft with an adapter sleeve. The measurement is performed automatically and the measured data is directly logged - specifically for each individual bearing.By developing an intelligent algorithm that adapts to different bearing configurations, the metrological determination of the test load became unnecessary. The trend of the test force was abstracted by a mechanical model and the characteris-tic curve correlated with the bearing clearance. Thus, the sensor technology originally required for this could be re-placed by an intelligent software system.The system that was developed can be incorporated into the quality control system of a rolling bearing manufacturer. It should also be used as a standardized method for checking the radial clearance of bearings after the assembly process.

Most of the bearing positions are designed with rolling bearings. Usually rolling bearings are manufactured with a cer-tain "bearing clearance". Bearing clearance is defined as the total distance through which one bearing ring can be moved relative to the other in the radial direction (radial clearance) or in the axial direction (axial clearance). The radial clearance of a bearing is of considerable importance if reliable operation expected. Correctly installed rolling bearings increase the lifetime and cause less energy loss. In case of radial rolling bearings with a tapered bore, which are fas-tened on the shaft with an adapter sleeve, the radial clearance is reduced during the process of mounting. There are known measuring devices, that allow to check the radial clearance fully automatically in the uninstalled state. Methods for checking the radial clearance in the installed state are known as well. The simplest method is the use of feeler gauges. Even simple measuring devices are known where the bearing is turned by hand and the radial clearance is read manually via a dial gauge. The measurements of these methods are sometimes subject to large fluctuations because each assembly operator is not performing the task exactly the same-human variation. The intent of this work is to develop a method for measuring radial clearance during the assembly process. The meas-urement result should be reproducible and not influenced by the assembly operator's natural variation while performing the task. For this reason, a measuring device was developed. The radial clearance can now be measured before, during and immediately after the process of mounting bearings with tapered bore which are fastened on the shaft with an adapter sleeve. The measurement is performed automatically and the measured data is directly logged-specifically for each individual bearing. By developing an intelligent algorithm that adapts to different bearing configurations, the metrological determination of the test load became unnecessary. The trend of the test force was abstracted by a mechanical model and the characteris-tic curve correlated with the bearing clearance. Thus, the sensor technology originally required for this could be re-placed by an intelligent software system. The system that was developed can be incorporated into the quality control system of a rolling bearing manufacturer. It should also be used as a standardized method for checking the radial clearance of bearings after the assembly process.

Bei der Erfindung handelt es sich um einen Messstand oder Gerät oder Teil davon zur automatisierten Messung der radialen Lagerluft vonWälzlagern vor und nach der Montage auf einer Welle. In ist der Aufbau der Messeinrichtung zur automatischen Erfassung der Lagerluft abgebildet.Zum variablen Verschieben der Messeinrichtung befindet sich an der Unterseite ein Bolzen (1) zum Abnehmen und Verstellen der gesamtenMesseinrichtung. Zentral in der Mitte der Zeichnung befindet sich eine Welle (2) mit einem darauf zu montierendem Lager (3). Der Elektromagnet (4)drückt den Außenring des Lagers nach oben, die hierbei erzeugte Kraft wird durch eine Kraftmessdose (5) erfasst und kann durch eine Regelungkonstant eingestellt werden. Der Weg, um den der Außenring des Lagers angehoben wird, wird von einer Messuhr (6) erfasst und gibt die vorhandenLagerluft bzw. das Spiel im Lager an. An der Oberseite der Messeinrichtung befindet sich ein weiterer Elektromagnet (7) mit Halteeinrichtung (8), der alsVibrationseinrichtung dient. Hierdurch wird dafür gesorgt, dass sich die Wälzkörper im Lager vor einer jeden Messung setzen.