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Integrated Approach for the Adjustment of Disruption Programs to the Actual Infrastructural Availability
Get PDFSo-called disruption programs (DRP) are used to deal with suddenly occurring disruptions in commuter railway systems. Since the creation of DRPs is a complicated task, they regularly to support disruptions that result due to the failure of a given set of infrastructural elements (e.g. signal boxes). In case a disruption affects a combination of infrastructural elements that are not explicitly covered by available DRPs, their benefits would be highly affected. Therefore, it becomes necessary to derive approaches that allow an ad-hoc adjustment of the DRPs to the actual infrastructure availability.
This article proposes an approach supporting the adjustment of a manually chosen DRP to the actual infrastructural availability. The approach performs the adjustments by means of a heuristic method. The heuristic method uses a local search to derive the necessary adjustments on the operational measures in the operating concept of the chosen DRP that are conflicting with the actual infrastructural availability. The local search method allows to minimize the extent of the adjustments, as it is considered that the optimal solution resides in the vicinity of the chosen DRP. Ultimately, the adjusted operating concept alternatives generated by the heuristic are assessed to ensure their operational and passenger-transport feasibilities
Cones of orthogonal Shimura subvarieties and equidistribution
Get PDFLet X be an orthogonal Shimura variety, and let Cᵣᵒʳᵗ(X) be the cone generated by the cohomology classes of orthogonal Shimura subvarieties in X of dimension r. We investigate the asymptotic properties of the generating rays of Cᵣᵒʳᵗ(X) for large values of r. They accumulate towards rays generated by wedge products of the Kähler class of X and the fundamental class of an orthogonal Shimura subvariety. We also compare Cᵣᵒʳᵗ(X) with the cone generated by the special cycles of dimension r. The main ingredient to achieve the results above is the equidistribution of orthogonal Shimura subvarieties
A Note on Alexandrov Immersed Mean Curvature Flow
Get PDFWe demonstrate that the property of being Alexandrov immersed is preserved along mean curvature flow. Furthermore, we demonstrate that mean curvature flow techniques for mean convex embedded flows such as noncollapsing and gradient estimates also hold in this setting. We also indicate the necessary modifications to the work of Brendle–Huisken to allow for mean curvature flow with surgery in the Alexandrov immersed, 2-dimensional setting
Der explizite Leser : Kognitionswissenschaftliche Herausforderungen für die Literaturwissenschaft zwischen Korpus- und Rezeptionsanalyse
Get PDFProduktion, Text und Rezeption sind die Gegenstandsfelder der klassischen, hermeneutischen Literaturwissenschaft. Der Beitrag argumentiert, dass diese Felder auch für die Digitale Literaturwissenschaft zusammengehören. Ergebnisse von Untersuchungen im data rich approach, der Korpusanalysen mit der Analyse von Daten aus der Institutionengeschichte der Literatur verbindet, erhärten die Notwendigkeit, sich stärker mit der Rezeptionsseite der Literatur zu befassen. Dazu gehört die Durchführung von Experimenten, deren empirische Daten in die Daten-Systematik der Literaturwissenschaft integriert werden müssen. Für diese Perspektive greift die rezeptionsästhetische Vorstellung vom ›impliziten Leser‹, der auf Textstrukturen nur reagiert, zu kurz. Vor dem Hintergrund neuer Evidenz aus der Kognitionswissenschaft wird gezeigt, dass Lesen immer auch der Eigengesetzlichkeit der dabei beteiligten kognitiven Prozesse unterliegt. Der ›explizite Leser‹ bietet die Möglichkeit, zentrale interdisziplinäre Fragen wie die nach der Funktionsweise von Aufmerksamkeit, nach der Wirkung von Narrativen oder nach den speziellen Wahrscheinlichkeitskalkülen der Literatur neu zu fassen und dies bei der Analyse zu berücksichtigen
Executing Ad-Hoc Queries on Large Geospatial Data Sets Without Acceleration Structures
Get PDFIn this case study, we investigate if it is possible to harness the capabilities of modern commodity hardware to perform ad-hoc queries on large raw geospatial data sets. Normally, this requires building an index structure, which is a time-consuming process. We aim to provide means to individual users who receive a new or updated geospatial data set and want to directly start working with it without having to build such an index structure first. To this end, we conduct various experiments on two distinct types of data: 3D building models and point clouds. For the former, we demonstrate that well-known algorithms such as fast string search allow a wide range of queries to be answered in at most a few seconds on data sets with over a million buildings. The usage of progressive indexing additionally improves query run time by more than a factor of two. Regarding point clouds, we achieve similar run times using the popular LAS file format and a query throughput of up to a billion points per second when using a columnar memory layout. The run time of ad-hoc queries is often on par with that of database-driven solutions, sometimes even outperforming them. Considering that ad-hoc queries require no preprocessing, our results show that they are a viable alternative to acceleration structures when working with geospatial data
Enzymatic synthesis of semi-IPNs within hydrogel-based microfluidics
Get PDFWith the goal of achieving environmentally friendly polymer synthesis strategies, enzyme-promoted polymerisation has gradually attracted people's attention. The development of hydrogel-based microfluidics provides a new carrier system for enzymatic catalysis. Here, we report a new technique for enzyme-promoted free radical polymerisation, supported on hydrogel microdots (μHDs) within a microfluidic chip. Free radical polymerisation initiated by free horseradish peroxidase (HRP) in vials confirmed the formation of poly(N-isopropyl acrylamide) (PNiPAAm), achieving high molecular weight (500 000 Da) in 5 min. For polymerisation in microfluidics, disulphide-bearing μHDs were mounted on a PDMS-on-glass chip. Utilising a disulphide-thiol exchange reaction, modified HRP was then captured “from the flow” through the chip, which was confirmed by fluorescence microscopy. Various polymerisation parameters were studied in the microfluidic chip, and the successful polymer formation was confirmed by copolymerisation with a fluorescent comonomer. The physical entanglement fixed the formed polymer on the μHDs, forming a structure similar to a semi-interpenetrating network (semi-IPN). Thus, this technique provides a new direct approach to achieving semi-IPNs within microfluidic chips, showcasing the versatility in which microfluidic systems can be utilised
Production and purification of molecular ²²⁵Ac at CERN-ISOLDE
Get PDFThe radioactive nuclide ²²⁵Ac is one of the few promising candidates for cancer treatment by targeted-α-therapy, but worldwide production of ²²⁵Ac faces significant limitations. In this work, the Isotope Separation On-Line method was used to produce actinium by irradiating targets made of uranium carbide and thorium carbide with 1.4-GeV protons. Actinium fluoride molecules were formed, ionized through electron impact, then extracted and mass-separated as a beam of molecular ions. The composition of the mass-selected ion beam was verified using time-of-flight mass spectrometry, α- and γ-ray decay spectrometry. Extracted quantities of ²²⁵Ac¹⁹F₂⁺ particles per μC of incident protons were 3.9(3)×10⁷ from a uranium carbide target and 4.3(4)×10⁷ for a thorium carbide target. Using a magnetic mass separator, the long-lived contamination ²²⁷Ac is suppressed to <5.47×10⁻⁷ (95% confidence interval) with respect to ²²⁵Ac by activity. Measured rates scale to collections of 108 kBqμA⁻¹h⁻¹ of directly produced ²²⁵Ac¹⁹F₂⁺
Quantitative comparison of a mobile, tablet-based eye-tracker and two stationary, video-based eye-trackers
Get PDFThe analysis of eye movements is a noninvasive, reliable and fast method to detect and quantify brain (dys)function. Here, we investigated the performance of two novel eye-trackers—the Thomas Oculus Motus-research mobile (TOM-rm) and the TOM-research stationary (TOM-rs)—and compared them with the performance of a well-established video-based eye-tracker, i.e., the EyeLink 1000 Plus (EL). The TOM-rm is a fully integrated, tablet-based mobile device that presents visual stimuli and records head-unrestrained eye movements at 30 Hz without additional infrared illumination. The TOM-rs is a stationary, video-based eye-tracker that records eye movements at either high spatial or high temporal resolution. We compared the performance of all three eye-trackers in two different behavioral tasks: pro- and anti-saccade and free viewing. We collected data from 30 human subjects while running all three eye-tracking devices in parallel. Parameters requiring a high spatial or temporal resolution (e.g., saccade latency or gain), as derived from the data, differed significantly between the EL and the TOM-rm in both tasks. Differences between results derived from the TOM-rs and the EL were most likely due to experimental conditions, which could not be optimized for both systems simultaneously. We conclude that the TOM-rm can be used for measuring basic eye-movement parameters, such as the error rate in a typical pro- and anti-saccade task, or the number and position of fixations in a visual foraging task, reliably at comparably low spatial and temporal resolution. The TOM-rs, on the other hand, can provide high-resolution oculomotor data at least on a par with an established reference system
The stochastic primitive equations with transport noise and turbulent pressure
Get PDFIn this paper we consider the stochastic primitive equation for geophysical flows subject to transport noise and turbulent pressure. Admitting very rough noise terms, the global existence and uniqueness of solutions to this stochastic partial differential equation are proven using stochastic maximal L²-regularity, the theory of critical spaces for stochastic evolution equations, and global a priori bounds. Compared to other results in this direction, we do not need any smallness assumption on the transport noise which acts directly on the velocity field and we also allow rougher noise terms. The adaptation to Stratonovich type noise and, more generally, to variable viscosity and/or conductivity are discussed as well
Procrustean Statistical Inference of Deformations
Get PDFA two step method has been devised for the statistical inference of deformation changes. In the first step of this method and based on Procrustes analysis of deformation tensors, the significance of the change in a time or space series of deformation tensors is statistically analyzed. In the second step significant change(s) in deformations are localized. In other words, they are assigned to certain parameters of deformation tensor. This is done using the Global Model Test. Because of the key role of Procrustes analysis in the proposed method for the inference of deformation changes, it has been given the name of Procrustean Statistical Inference of Deformations. The method has been implemented to synthetic and real deformations. The 3D-deformation tensors of a regional GPS network in the Kenai Peninsula, for analyzing the spatial variation of deformation tensors or the change of deformation within the study area, and a local GPS network in France, for analyzing the temporal variation of deformation tensors or the change of deformation in time at every point of the network in the study area have been used for illustrating the practical application of the proposed method