56 research outputs found
Accurate measurement of energy dissipated in braking rheostats in DC railway systems
This paper describes the measurement system used to monitor the energy dissipated in the braking rheostat resistors on board a locomotive operating in a DC rail system. The aim of the activity is the accurate estimation of the energy, nowadays wasted, that could be recovered thanks to the implementation of the smart grid paradigm in the DC railway system. To provide metrological reliability to the measured wasted energy, a preliminary identification and estimation of the uncertainty is provided. The target uncertainty of the measurements is 1 %
Genetic Fingerprint of Immunosuppression Following Half-marathon Running in Microarray Study
ABSTRACT
Introduction: An acute bout of exhaustive exercise such as marathon or half-marathon running can interfere with immunity, reflected by transient immunosuppression and inflammation like reaction following the event. To gain more insights into these mechanisms, the capacity of whole blood cultures in profiling gene expression in response to endotoxin (LPS) was studied in athletes before, 30min after, 3h after and 24h after a half-marathon run. Methods: Four well trained men and 4 well trained women participated and gene expression patterns were assessed in LPS-stimulated (1h) and unstimulated whole blood using Affymetrix GeneChip microarrays. Results: exercise significantly altered several genes in LPS-stimualted and unstimulated blood cultures of male and female athletes. A row of genes with prominent anti-inflammatory function were strongly up-regulated in unstimulated cultures in both sexes (ARG-1, SOCS3, DUSP-1, BMX, GOS2, CD177, and GJB6). In the same cultures a row of highly inflammatory and apoptotic genes were down-regulated (Granzymes A-M-B-K-H, PRF1, SPON2, Granulysin, KLRF1, PLEKHF1). Some of these genes which were significantly up-or down-regulated in unstimulated cultures were also strongly regulated in LPS-stimulated cultures (GJB6, ARG-1, ORM2, KLRF1, TRA@///TRD@, Granzymes, SPON2). In addition, there were some strongly regulated genes which could only be detected in LPS-stimulated cultures but not in unstimulated cultures. Among these, TNIP3, PLAU, HIVEP1, and SLED were up-regulated and IFN-β, IFN-γ, L-12B, CXCL4. CXCL10 and TRAF1 were significantly down-regulated. Conclusion: there is a row of genes which are strongly regulated through exercise but can only be detected in (endotoxin) stimulated cultures. This is direct evidence showing that the response to pathogens is strongly down-regulated following prolonged exhaustive exercise through different ways
Flächenauswahlprozess und dynamische Optimierung zur Ermittlung von wertstromdurchgängigen Autoidentifikationstechnologien
Eine wesentliche Voraussetzung intelligenter und vernetzter Produktionssysteme sind Bauteile als Informationsträger, welche in der Lage sind mit den Produktionsressourcen zu kommunizieren. Die Kommunikation erfolgt mittels Autoidentifikationstechnologien. Die vorliegende Arbeit zeigt einen Flächenauswahlprozess auf als auch ein Vorgehen zur Ermittlung wertstromdurchgängiger Autoidentifikationstechnologien für die Umsetzung von Bauteilen als Informationsträger
Pantograph arc location estimation using resonant frequencies in DC railway power systems
Pantograph arcing in electrified railway systems not only reduces the power collection quality of a locomotive but can also damage pantograph strips and overhead lines (OHLs). Most research detects pantograph-to-OHL arcs based on onboard voltage/current measurements, pantograph cameras, and so on. The use of onboard voltage/current data, though being cost-effective, rarely reflects arc locations along OHLs. This article develops an arc positioning method, which matches the position-dependent resonant frequency (RF) of an OHL with the RF extracted from voltage measurements in a pantograph arc event. A particular 20-km DC railway line supplied by two substations is first modelled in MATLAB/Simulink, with the model effectiveness being assessed based on voltage measurements in an arc event. Then, the OHL-related RFs estimated by the model are validated by the Tableau formula and discussed alongside impacts on RFs based on line models, locomotive locations, and line lengths. These evaluations permit the generation of an RF curve that links OHL-related RFs with arc locations. The arc positioning method is tested based on the pantograph arc events presumed at various positions along the 20-km line, showing errors within 0.2 km at certain locations. The ability to determine arc locations will permit periodic inspections to be performed on the determined line sections
Neutral sphingomyelinase mediates the co-morbidity trias of alcohol abuse, major depression and bone defects
Mental disorders are highly comorbid and occur together with physical diseases, which are often considered to arise from separate pathogenic pathways. We observed in alcohol-dependent patients increased serum activity of neutral sphingomyelinase. A genetic association analysis in 456,693 volunteers found associations of haplotypes of SMPD3 coding for NSM-2 (NSM) with alcohol consumption, but also with affective state, and bone mineralisation. Functional analysis in mice showed that NSM controls alcohol consumption, affective behaviour, and their interaction by regulating hippocampal volume, cortical connectivity, and monoaminergic responses. Furthermore, NSM controlled bone–brain communication by enhancing osteocalcin signalling, which can independently supress alcohol consumption and reduce depressive behaviour. Altogether, we identified a single gene source for multiple pathways originating in the brain and bone, which interlink disorders of a mental–physical co-morbidity trias of alcohol abuse—depression/anxiety—bone disorder. Targeting NSM and osteocalcin signalling may, thus, provide a new systems approach in the treatment of a mental–physical co-morbidity trias
Multiple star systems in the Orion nebula
This is the author accepted manuscript. The final fersion is available from EDP Sciences via the DOI in this record.This work presents an interferometric study of the massive-binary fraction in the Orion Trapezium cluster with the recently comissioned GRAVITY instrument. We observed a total of 16 stars of mainly OB spectral type. We find three previously unknown companions for θ1 Ori B, θ2 Ori B, and θ2 Ori C. We determined a separation for the previously suspected companion of NU Ori. We confirm four companions for θ1 Ori A, θ1 Ori C, θ1 Ori D, and θ2 Ori A, all with substantially improved astrometry and photometric mass estimates. We refined the orbit of the eccentric high-mass binary θ1 Ori C and we are able to derive a new orbit for θ1 Ori D. We find a system mass of 21.7 M⊙ and a period of 53 days. Together with other previously detected companions seen in spectroscopy or direct imaging, eleven of the 16 high-mass stars are multiple systems. We obtain a total number of 22 companions with separations up to 600 AU. The companion fraction of the early B and O stars in our sample is about two, significantly higher than in earlier studies of mostly OB associations. The separation distribution hints toward a bimodality. Such a bimodality has been previously found in A stars, but rarely in OB binaries, which up to this point have been assumed to be mostly compact with a tail of wider companions. We also do not find a substantial population of equal-mass binaries. The observed distribution of mass ratios declines steeply with mass, and like the direct star counts, indicates that our companions follow a standard power law initial mass function. Again, this is in contrast to earlier findings of flat mass ratio distributions in OB associations. We excluded collision as a dominant formation mechanism but find no clear preference for core accretion or competitive accretion.Marie Skłodowska-Curie Grant AgreementFCT-PortugalERC Starting Gran
Hochratesynthese von Hartstoffschichten auf Siliciumbasis mittels thermischer Plasmen
Mittels thermischer Plasmen werden Hartstoffschichten auf der Basis von Silicium - SiC, Si3N4 sowie ternäre Si-C-N Verbindungen, aus flüssigen Single Precursoren synthetisiert. Durch die hohen Abscheideraten von bis zu 1.500 µm/h wird das hohe Potenzial der Beschichtungswerkstoffe für den Schutz von Bauteilen, die starken Verschleiß- und Korrosionsbeanspruchungen insbesondere bei hohen Temperaturen ausgesetzt sind, bei wirtschaftlich interessanten Prozesszeiten nutzbar. Der Einfluss der Precursorstruktur und der Prozessführung auf die Mikrostruktur der Schichten sowie die Abscheiderate wird systematisch erarbeitet. Zur Schichtcharakterisierung kommen Lichtmikroskopie, REM, EDX, XRD und im Fall röntgenamorpher Schichten FTIR zum Einsatz. Das Verwenden unterschiedlicher thermischer Plasmen erlaubt das Einstellen eines weiten Prozessfeldes. Mit Hilfe von Enthalpiesonden Messungen werden die Einflüsse der Maschinenparameter auf den Prozesszustand untersucht. Die Ergebnisse sind in einer Prozess - Gefügekarte zusammengefasst. Da das Gefüge der Schichten die Eigenschaften im Einsatz bedingt, bieten diese Arbeiten die Grundlage für das reproduzierbare Herstellen von Schichten mit angepassten Eigenschaften. Über die emissionsspektroskopischen Analysen zu den plasmachemischen Reaktionen gelingt es, die Schichtabscheidemechanismen in Abhängigkeit von den Prozessparametern zu klären und einen Ansatz für eine online Prozesskontrolle zu erarbeiten
Methodik zur Wertstromintegration einer aktiven Bauteilrückverfolgung in die diskrete Variantenfertigung
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