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Raw Materials - Recycler, Chemical Industry, and Plastic Manufacturer
No full text251301Chapter 10 deals with the recyclate production based on technologies currently in use and under development. Depending on the technology used, recyclates are produced as a secondary raw material for further processing by various players such as mechanical recyclers, the chemical and plastics manufacturing industries. The fundamental technological principles of mechanical recycling of plastic waste are shown in Sect. 10.1. The various pre-treatment processes are covered in detail, as well as extrusion, melt filtration, odor removal and process water treatment. Beyond the technological description, the outlook draws conclusions on the further development of mechanical recycling in a changing economic and regulatory environment. Section 10.2 gives an overview of the quality improvement methods of recycled plastics to obtain recyclates for closed-loop and high-value applications. Key steps for high-grade materials in the thermal transformation process from regrind to recyclate compound are smooth processing, degassing steps to remove volatiles, and the addition of stabilizers to avoid polymer degradation and maintain the properties. Additives such as tailor-made products for restabilization, compatibilizers, chain-extenders or odor-reducing agents are described in terms of their functionality and significance for quality improvement of recyclates. Section 10.3 provides an up-to-date overview of the development status of various chemical recycling processes, including the overlap with physical recycling processes. Based on the current input and output capacities of chemical and physical recycling plants in Europe, estimates of future capacity development in Europe and the world are made based on investment announcements. In Sect. 10.4, the reader will find a case study of how a global chemical company is pursuing its own strategy to actively shape and participate in the circular economy to become a future supplier of circular feedstocks. Time, capital investments, and organizational changes are outlined based on published communication. This demonstrates that ambitious timelines are key to establishing a circular economy based on business models
Effective Inelastic Bending Behavior of Multi-Wire Cables Using Finite Elements Accounting forWire Contact
No full text369379This contribution focuses on the investigation of inelastic structural effects occurring during the bending deformation of cables using detailed finite element models of helix wire strands. Due to the complex structure of cables usually consisting of concentric layers of intertwined wires, shields and the outer jacket, inelastic deformation behaviour has to be expected. In this work, we model simplified cables as strands of helix wires discretised with quadratic beam elements to investigate the influence of geometric parameters such as the helix angle of the wires and the interactions of the wires by means of frictionless or frictional contact models. Starting at low model complexity, we use double wire and seven wire models to simulate pure bending of intertwined strands omitting material inelasticity to avoid superposition of structural and material effects. Different variations of contact states in the undeformed configuration of the seven wire strand are taken into account allowing for the direct observation of the influence of active contacts on the strand’s bending response. First steps towards modelling the interactions between wires and objects relevant in cable bundle assembly, e.g. cable ties or clips, are presented for the double wire model. The presented models yield a valuable toolbox for the investigation of specific structural parameters affecting the deformation behaviour of cables
A Qualitative Analysis of the German Road Traffic Regulations (StVO) for Automated Driving
No full textAn Automated Driving Systems (ADS) must comply with traffic regulations that are still primarily written for human drivers, such as the German Road Traffic Regulations (StVO). Automatically assessing legal compliance remains a key challenge, as existing formalization approaches typically cover only limited rule subsets. In this paper, we present a comprehensive qualitative analysis of the StVO, focusing on regulations relevant to passenger vehicles. Using inductive coding, we categorize legal concepts, quantify the relevant share of the regulation that apply to ADSs, and identify recurring sentence structures. The analysis highlights structural limitations such as vague formulations, implicit assumptions, and missing quantification that hinder formalization and verification of ADSs. Based on our results, we motivate recommendations for future legislation that is better suited for automated interpretation and monitoring
Neural Network-Powered Finger-Drawn Biometric Authentication
No full textThis paper investigates neural network-based biometric authentication using finger-drawn digits on touchscreen devices. We evaluated CNN and autoencoder architectures for user authentication through simple digit patterns (0-9) traced with finger input. Twenty participants contributed 2,000 fingerdrawn digits each on personal touchscreen devices. We compared two CNN architectures: a modified Inception-V1 network and a lightweight shallow CNN for mobile environments. Additionally, we examined Convolutional and Fully Connected autoencoders for anomaly detection. Both CNN architectures achieved ∼89% authentication accuracy, with the shallow CNN requiring fewer parameters. Autoencoder approaches achieved ∼75% accuracy. The results demonstrate that finger-drawn symbol authentication provides a viable, secure, and user-friendly biometric solution for touchscreen devices. This approach can be integrated with existing pattern-based authentication methods to create multilayered security systems for mobile applications
Influence of a Two-Cut-Strategy on Tool Wear in Gear Hobbing
No full text225234This report addresses both the empirical and theoretical analysis of a two-cut strategy for gear hobbing with conventional hobs. Tool life and wear behavior of PM-HSS S390 tools are analyzed in fly-cutting trials when machining 20MnCr5 case-hardening steel. By varying the axial feed rate in the first and the second cut, the influence of the interaction between both cuts on the tool wear is investigated. The results are compared to wear measurements from trials conducted with a one-cut strategy. It was shown that at the underlying test conditions, the average proportion of wear in the second cut was about 4%. For a better understanding of the interaction between the two cuts, load collectives were formed based on characteristic chip values calculated with SPARTApro. The collectives were evaluated with regard to the tool life.Part F113
Pupil slicer at high throughput for the EXtreme Precision Spectrograph (EXPRES) at the Lowell Discovery Telescope
No full textThe free-space pupil slicer of Yale University's EXtreme PREcision Spectrograph (EXPRES) at Lowell Observatory's Lowell Discovery Telescope (LDT) is placed in the beam conditioning sub-system of the spectrograph in between fiber feeds for an incoming science fiber at octagonal core dimensions of 66 µm, and a respective outgoing rectangular fiber at half the width and twice the height of the octagonal fiber with core dimensions of 132 x 33 µm2. At this location efficient slicing is accomplished between 380 nm and 680 nm because the near- and far-fields are swapped within a double-scrambler arrangement, thus providing a location to image the pupil. The resolution for EXPRES is ca. 150.000 (the spectrograph design without slicing has a resolution of 75.000), thus the pupil gets sliced two times, and the two images are injected into a rectangular fiber ca. 33x132 µm2 that matches the spectrograph slit at a f-number of 1/4. The pupil slicer provides a throughput of >85%, having only modest losses from reflections on the implemented, precision and miniaturized optics, as well as alignment errors, and the injection of light into the rectangular fiber. We report about the pupil slicer's design, integration and alignment features
Analysis of time-resolved thermal responses in Lock-In thermography by independent component analysis (ICA) for a 3D-spatial separation of weak thermal sources and defects
No full text611Lock-In Thermography is an established non-destructively operating method for the analysis of failures in microelectronic devices. In recent years a major improvement was achieved allowing the acquisition of the time-resolved temperature responses of weak thermal spots that enhances defect localization in 3D stacked semiconductor architectures. The assessment of a defect’s depth based on the numerical estimation of the delay between excitation and thermal response by analyzing the value of the lock-in phase is often prone to thermal noise and parasitic effects. In sample structures that contain partial or full transparence for the infrared signal between the origin and the sample surface, the interference of the direct (radiated) and the conducted signal component largely falsifies the phase value on which the classical depth estimation relies. In the present study blind source separation based on independent component analysis of the thermal signals was successfully applied to separate interfering signal components arising from direct thermal radiation and conduction for a precise estimation of the defect depth
Development of a Framework for Wind Turbine Design and Optimization
No full text105128Dimensioning and assessment of a specific wind turbine imply iterative steps for design optimization, as well as load calculations and performance analyses of the system in various environmental conditions. However, due to the complexity of wind turbine systems, fully coupled aero-hydro-servo-elastic codes are indispensable to represent and simulate the non-linear system behavior. To cope with the large number of simulations to be performed during the design process of a wind turbine system, automation of simulation executions and optimization procedures are required. In this paper, such a holistic simulation and optimization framework is presented, by which means iterative simulations within the wind turbine design assessment and development processes can be managed and executed in an automated and high-performance manner. The focus lies on the application to design load case simulations, as well as the realization of automated optimizations. The proper functioning and the high flexibility of the framework tool is shown based on three exemplary optimization tasks.2
Identification and characterization of the anti-viral interferon lambda 3 as direct target of the Epstein-Barr virus microRNA-BART7-3p
No full textThe human Epstein–Barr virus (EBV), as a member of the human γ herpes viruses (HHV), is known to be linked with distinct tumor types. It is a double-stranded DNA virus and its genome encodes among others for 48 different microRNAs (miRs). Current research demonstrated a strong involvement of certain EBV-miRs in molecular immune evasion mechanisms of infected cells by, e.g., the disruption of human leukocyte antigen (HLA) class Ia and NKG2D functions. To determine novel targets of EBV-miRs involved in immune surveillance, ebv-miR-BART7-3p, an EBV-encoded miR with high expression levels during the different lytic and latent EBV life cycle phases, was overexpressed in human HEK293T cells. Using a cDNA microarray-based comparative analysis, 234 (229 downregulated and 5 upregulated) deregulated human transcripts were identified in ebv-miR-BART7-3p transfectants, which were mainly involved in cellular processes and molecular binding. A statistically significant downregulation of the anti-proliferative and tumor-suppressive hsa-miR-34A and the anti-viral interferon lambda (IFNL)3 mRNA was found. The ebv-miR-BART7-3p-mediated downregulation of IFNL3 expression was due to a direct interaction with the IFNL3 3’-untranslated region (UTR) as determined by luciferase reporter gene assays including the identification of the accurate ebv-miR-BART7-3p binding site. The effect of ebv-miR-BART7-3p on the IFNL3 expression was validated both in human cell lines in vitro and in human tissue specimen with known EBV status. These results expand the current knowledge of EBV-encoded miRs and their role in immune evasion, pathogenesis and malignant transformation.12
Comprehensively Analyzing the Impact of Cyberattacks on Power Grids
No full text10651081The increasing digitalization of power grids and especially the shift towards IP-based communication drastically increase the susceptibility to cyberattacks, potentially leading to blackouts and physical damage. Understanding the involved risks, the interplay of communication and physical assets, and the effects of cyberattacks are paramount for the uninterrupted operation of this critical infrastructure. However, as the impact of cyberattacks cannot be researched in real-world power grids, current efforts tend to focus on analyzing isolated aspects at small scales, often covering only either physical or communication assets. To fill this gap, we present Wattson, a comprehensive research environment that facilitates reproducing, implementing, and analyzing cyberattacks against power grids and, in particular, their impact on both communication and physical processes. We validate Wattson's accuracy against a physical testbed and show its scalability to realistic power grid sizes. We then perform authentic cyberattacks, such as Industroyer, within the environment and study their impact on the power grid's energy and communication side. Besides known vulnerabilities, our results reveal the ripple effects of susceptible communication on complex cyber-physical processes and thus lay the foundation for effective countermeasures