371 research outputs found
Investigations of the deformation and burden demolition behaviour at a quay construction
Eine Kaikonstruktion ist ein vielfach statisch unbestimmtes System, dessen Tragverhalten durch komplexe Interaktionen der Tragelemente untereinander und mit dem Boden bestimmt wird. Zur Lösung des Standsicherheitsproblems wird die Konstruktion durch Zerlegung in Teilsysteme vereinfacht. Die fĂŒr Kaikonstruktionen verwendeten Belastungsannahmen und Berechnungsmethoden beruhen auf langjĂ€hrigen Erfahrungen und Untersuchungen. Ein Ziel solcher Untersuchungen war und ist es, das Trag- und Verformungsverhalten einzelner Bauteile in der Gesamtkonstruktion zu ermitteln. Aus wissenschaftlicher Sicht kann hier von einem in-situ-GroĂversuch gesprochen werden. Messungen an der Kaimauerwand haben ergeben, dass die GĂŒltigkeit des Ansatzes des aktiven Erddruckes bestĂ€tigt werden kann. Die theoretisch erforderlichen Bewegungen zur Weckung des vollen Erdwiderstandes konnten messtechnisch nicht festgestellt werden, dennoch herrscht im Gesamtsystem Gleichgewicht, wie ein Vergleich der auftretenden HorizontalkrĂ€fte bestĂ€tigt. Mit UnterstĂŒtzung geodĂ€tischer Kopfpunkteinmessungen kann eine Gesamtbewegung der Kaikonstruktion zur Wasserseite gezeigt werden, in der sich auch in geringerem Umfang der WandfuĂ bewegt. Das Tragverhalten der Gesamtkonstruktion wird mit einer numerischen Berechnung weiter untersucht. Aus der numerischen Berechnung ergeben sich vergleichbare Ergebnisse hinsichtlich der gemessenen Verformungen am Gesamtsystem. Die Untersuchungen zum Lastabtragungs- und Verformungsverhalten an einer Kaikonstruktion haben gezeigt, dass die Vorgehensweise bei der Berechnung der Standsicherheit einer Kaikonstruktion richtig ist. Die Vereinfachung des vielfach statisch unbestimmten Systems in statisch bestimmte Teilsysteme, deren ReaktionskrĂ€fte oder -spannungen als Belastungen auf benachbarte Bauteile anzusetzen sind, ergibt grundsĂ€tzlich ausreichende Sicherheiten bei der Dimensionierung der Konstruktion.A Quay Construction is a multiply indeterminate static system, whose sustaining behaviour is determined through complex interactions of its base elements between each other and with the ground. To resolve the stability problem, its complexity is reduced by dismantling the construction into subsystems. The load assumptions and calculation methods employed for analyzing quay constructions are based on long-standing experiences and investigations. The goal of such investigations is to determine the sustaining and deforming behaviour of individual components in the compound construction. Seen in a scientific perspective, this task can be regarded as a large-scale in-situ-test. Measurements at the quay wall confirm the validity of the approach of the acting earth pressure. The theoretically expected movement for initiating the full ground resistance could not ascertained by measurements. Nevertheless, a balance of power does exist in the compound system, as demonstrated by comparison of the resulting level forces. Using geodesic measurements, a movement of the entire quay construction and a smaller movement of the basement of the wall, both directed to the water front, can be represented. The sustaining behaviour of the construction is further subjected to a numerical analysis. Comparable results referring to the measured deformations of the compound system arise from the numerical calculation. The investigations of the burden demolition and deformation behaviour at a quay construction have verified the correctness of the method for calculating the stability of a quay construction. The breakdown of the multiply indeterminate static system into statically determinate subsystems, whose reaction forces or tensions are to be applied onto neighboring components, shows fundamentally sufficient safety in dimensioning the construction
Development of a virtual sensor for the comparison of heat partitions in milling under cryogenic cooling lubrication and high-pressure cutting fluid supply
Simple renormalizable flavor symmetry for neutrino oscillations
pre-printThe recent measurement of a nonzero neutrino mixing angle Ξ13 requires a modification of the tri-bimaximal mixing pattern that predicts a zero value for it. We propose a new neutrino mixing pattern based on a spontaneously broken A4 flavor symmetry and a type-I seesaw mechanism. Our model allows for approximate tri-bimaximal mixing and nonzero Ξ13, and contains a natural way to implement low- and high-energy CP violations in neutrino oscillations, and leptogenesis with a renormalizable Lagrangian. Both normal and inverted mass hierarchies are permitted within 3Ï experimental bounds, with the prediction of small (large) deviations from maximality in the atmospheric mixing angle for the normal (inverted) case. Interestingly, we show that the inverted case is excluded by the global analysis in 1Ï experimental bounds, while the most recent MINOS data seem to favor the inverted case. Our model make predictions for the Dirac CP phase in the normal and inverted hierarchies, which can be tested in near-future neutrino oscillation experiments. Our model also predicts the effective mass |mee| measurable in neutrinoless double beta decay to be in the range 0:04 †|mee| †0:15 eV for the normal hierarchy and 0:06 †|mee| †0:11 eV for the inverted hierarchy, both of which are within the sensitivity of the next generation experiments
Mass Loss and Displacement Modeling for Multi-Axis Milling
During the cutting process, material of the workpiece is continuously being
removed by the cutting tool, which results in a reduction of mass as well as a
displacement in the center of the workpiece mass. When using workpiece sided
force sensors, such as table dynamometers, the total mass and the displacement
of the center of mass affects the force measurement due to gravitational and
inertial effects. The high flexibility of the milling process leads to a
complex change of volume and mass and necessitates the consideration of the
engagement conditions between tool and workpiece along the tool path in order
to estimate changes in mass and center of mass. This paper proposes a method
for estimating the mass loss and the displacement of the center of mass during
multi-axis milling processes. In this method the tool gets numerically sliced
along the tool axis and the workpiece removal for each slice along an arbitrary
tool path gets calculated. To validate the mass loss model, experiments in both
three-axis milling as well as multi-axis milling processes have been conducted.
Since it is difficult to measure the center of mass, validation for the
displacement of the center of mass was done by comparison with data extracted
from CAD. The results show good agreement between the simulated and measured
mass loss using the proposed approach
A Case for Integrated Data Processing in Large-Scale Cyber-Physical Systems
Large-scale cyber-physical systems such as manufacturing lines generate vast amounts of data to guarantee precise control of their machinery. Visions such as the Industrial Internet of Things aim at making this data available also to computation systems outside the lines to increase productivity and product quality. However, rising amounts and complexities of data and control decisions push existing infrastructure for data transmission, storage, and processing to its limits. In this paper, we exemplarily study a fine blanking line which can produce up to 6.2 Gbit/s worth of data to showcase the extreme requirements found in modern manufacturing. We consequently propose integrated data processing which keeps inherently local and small-scale tasks close to the processes while at the same time centralizing tasks relying on more complex decision procedures and remote data sources. Our approach thus allows for both maintaining control of field-level processes and leveraging the benefits of âbig dataâ applications
Schlussbericht zum BMBF-Vorhaben "KUBA - Nachhaltige Kunststoffwertschöpfungskette: Pilotfall Kunststoffe in Bauwirtschaft und GebÀuden
Effect of the relative shift between the electron density and temperature pedestal position on the pedestal stability in JET-ILW and comparison with JET-C
The electron temperature and density pedestals tend to vary in their relative radial positions, as observed in DIII-D (Beurskens et al 2011 Phys. Plasmas 18 056120) and ASDEX Upgrade (Dunne et al 2017 Plasma Phys. Control. Fusion 59 14017). This so-called relative shift has an impact on the pedestal magnetohydrodynamic (MHD) stability and hence on the pedestal height (Osborne et al 2015 Nucl. Fusion 55 063018). The present work studies the effect of the relative shift on pedestal stability of JET ITER-like wall (JET-ILW) baseline low triangularity (\u3b4) unseeded plasmas, and similar JET-C discharges. As shown in this paper, the increase of the pedestal relative shift is correlated with the reduction of the normalized pressure gradient, therefore playing a strong role in pedestal stability. Furthermore, JET-ILW tends to have a larger relative shift compared to JET carbon wall (JET-C), suggesting a possible role of the plasma facing materials in affecting the density profile location. Experimental results are then compared with stability analysis performed in terms of the peeling-ballooning model and with pedestal predictive model EUROPED (Saarelma et al 2017 Plasma Phys. Control. Fusion). Stability analysis is consistent with the experimental findings, showing an improvement of the pedestal stability, when the relative shift is reduced. This has been ascribed mainly to the increase of the edge bootstrap current, and to minor effects related to the increase of the pedestal pressure gradient and narrowing of the pedestal pressure width. Pedestal predictive model EUROPED shows a qualitative agreement with experiment, especially for low values of the relative shift
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