Publication Server of Aschaffenburg University
Not a member yet
1531 research outputs found
Sort by
Design and testing of a Kirkpatrick-Baez optics variation
Beside Wolter I X-ray optics, which are used at most in currently operating X-ray space telescopes, there exist also other optical designs and their usability for space observations is still the matter of studies. This article covers preliminary testing results of an optical module which is based on a modified Kirkpatrick-Baez optics. This X-ray optics, consisting of four sub-modules, was assembled in Prague and tested at the PANTER test facility of MPE afterward. The sub-modules use different reflective coatings, in part developed by our research group, on complementary flat mirrors, which approximate the shape of a Kirkpatrick-Baez optical design. In this contribution we summarise the design of the optical modules, the details of applied coating layers, and the X-ray characterisation results at the PANTER test facilit
Hybride Hochschulausbildung als erfolgreiches Sales Enablement Training
Um im technischen Vertrieb erfolgreich zu sein, bedarf es umfassender Kenntnisse bei der Vorbereitung und Durchführung von Verhandlungen, auch im interkulturellen Kontext. Dabei gilt es für Berufsanfängerinnen und Berufsanfänger, möglichst frühzeitig Erfahrungen auf diesem Gebiet zu sammeln. Hierfür eignen sich insbesondere spezialisierte Vertriebsstudiengänge. Der Studiengang Internationales Technisches Vertriebsmanagement der TH Aschaffenburg bildet Vertriebsingenieurinnen und -ingenieure u. a. durch Sales-Enablement-Trainings aus, in denen die Studierenden in interaktiven Seminaren praxisnahe Verhandlungen durchführen. Im internationalen Vergleich schneiden diese dabei hervorragend ab, was Sales Contests auf Hochschulebene belegen. Darüber hinaus fassen die Absolventinnen und Absolventen dieses Studiengangs in der Industrie schnell Fuß und erreichen bald leitende Positionen in Vertriebsabteilungen
Networks and Islands of Genome Nano-architecture and Their Potential Relevance for Radiation Biology
The cell nucleus is a complex biological system in which simultaneous reactions and functions take place to keep the cell as an individualized, specialized system running well. The cell nucleus contains chromatin packed in various degrees of density and separated in volumes of chromosome territories and subchromosomal domains. Between the chromatin, however, there is enough “free” space for floating RNA, proteins, enzymes, ATPs, ions, water molecules, etc. which are trafficking by super- and supra-diffusion to the interaction points where they are required. It seems that this trafficking works somehow automatically and drives the system perfectly. After exposure to ionizing radiation causing DNA damage from single base damage up to chromatin double-strand breaks, the whole system “cell nucleus” responds, and repair processes are starting to recover the fully functional and intact system. In molecular biology, many individual epigenetic pathways of DNA damage response or repair of single and double-strand breaks are described. How these responses are embedded into the response of the system as a whole is often out of the focus of consideration. In this article, we want to follow the hypothesis of chromatin architecture’s impact on epigenetic pathways and vice versa. Based on the assumption that chromatin acts like an “aperiodic solid state within a limited volume,” functionally determined networks and local topologies (“islands”) can be defined that drive the appropriate repair process at a given damage site. Experimental results of investigations of the chromatin nano-architecture and DNA repair clusters obtained by means of single-molecule localization microscopy offer hints and perspectives that may contribute to verifying the hypothesis
Holographic multi-spot generation for ultra-short pulse Bessel beam processing of stainless steel
Advanced Control Methods for High Performance Dual Two-Level Inverter for Traction Application
The topology of the dual two-level inverter in combination with an electrical machine with open-end winding is an optimal
solution for the realization of high requirements from the automotive sector for high-performance traction drives. In this
publication, methods for extending the operating range and improving output voltage and current quality are presented
for synchronous as well as asynchronous PWM methods for the entire operating range for this system configuration.
Emphasis is placed on symmetrical power sharing between the inverters to maximize the power range. Optimal integration
of the system is achieved by the topology-related possibility of DC fast charging of the energy storages from a DC grid
without an additional charging unit
Röntgenteleskop-Funktionstests durch Beobachtung astronomischer Objekte am sichtbaren Nachthimmel
Lobster-Eye-Röntgenteleskope nutzen reflektierende Planspiegel unter streifendem Einfall und zeichnen sich durch ein großes Beobachtungsfeld aus. Die Spiegel reflektieren auch sichtbare Strahlung hervorragend. Nach Röntgen-messungen im Labor wurden nun weitere Tests durchgeführt, um die Abbildungs-eigenschaften mit realen Objekten des sichtbaren Himmels zu untersuchen
Automatic track guidance of industrial trucks using AI-based controllers with disturbance compensation
This paper presents a new control concept for automatic track guidance of industrial trucks in intralogistic systems. It is based on Reinforcement Learning (RL), a method of Artificial Intelligence (AI). The presented approach is able to adapt itself to different industrial truck variants and to the associated specific vehicle parameters. In order to avoid starting the whole training of the controller for each truck variant from scratch, the training process is divided into two steps. In the first step, the controller is trained on a model using parameters of a nominal vehicle variant. Based on this, the control parameters are only fine-tuned in the second step. In this way the controller is adapted to the actual truck variant and the corresponding parameter values. Moreover, the influence of the disturbance variable of the system (path curvature) is compensated by considering this a priori knowledge within the control design. Therefore, the Artificial Neural Networks (ANN) of the RL controller and the observation vector are suitably adjusted. In this way, the occurring path curvatures can be considered in both training steps and the control parameters can be optimized accordingly. Thus, the influence of the disturbance variable can be compensated, which significanlty improves the control quality. In order to demonstrate this, the new approach is compared to a RL control concept, not considering the disturbance variable and to a classical two-degrees-of-freedom (2DoF) control approach
Functional connectivity and convolutional neural networks for automatic classification of EEG data
Automatische Spurführung von Flurförderzeugen mittels KI
Im Verbundprojekt KAnIS forscht die TH Aschaffenburg mit Linde Material Handling an neuen KI-basierten Algorithmen zur querdynamischen Fahrzeugführung von Flurförderzeugen. Ziel des Projekts ist die Entwicklung eines universell einsetzbaren Regelungskonzepts, das verschiedene Arten von Flurförderzeugen automatisch führt, im Betrieb auftretenden Fahrzeugparameterschwankungen gezielt Rechnung trägt und darüber hinaus auch den jeweiligen Fitnesszustand der Fahrzeuge berücksichtigt
Femtosecond Laser-Based Micromachining of Rotational-Symmetric Sapphire Workpieces
Sapphire is a robust and wear-resistant material. However, efficient and high-quality micromachining is still a challenge. This contribution demonstrates and discusses two novels, previously unreported approaches for femtosecond laser-based micromachining of rotational-symmetric sapphire workpieces, whereas both methods are in principal hybrids of laser scanning and laser turning or laser lathe. The first process, a combination of a sequential linear hatch pattern in parallel to the workpiece’s main axis with a defined incremental workpiece rotation, enables the fabrication of sapphire fibers with diameters of 50 µm over a length of 4.5 mm. Furthermore, sapphire specimens with a diameter of 25 µm over a length of 2 mm can be fabricated whereas an arithmetical mean height, i.e., Sa parameter, of 281 nm is achieved. The second process combines a constant workpiece feed and orthogonal scanning with incremental workpiece rotation. With this approach, workpiece length limitations of the first process are overcome and sapphire fibers with an average diameter of 90 µm over a length of 20 cm are manufactured. Again, the sapphire specimen exhibits a comparable surface roughness with an average Sa value of 249 nm over 20 cm. Based on the obtained results, the proposed manufacturing method paves an innovative and flexible, all laser-based way towards the fabrication or microstructuring of sapphire optical devices, and thus, a promising alternative to chemical processes