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Globale Tendenzen in nationalen Cybersicherheitsstrategien: Ein Leitfaden für die Strategieentwicklung
No full text92108Der vorliegende Beitrag strengt einen Vergleich aller nationaler Cybersicherheitsstrategien weltweit an, um grundlegende globale Tendenzen herauszuarbeiten, die für zukünftige Strategieentwicklungsprozesse als Orientierungspunkte gelten und potenziell eine Vorbildwirkung entfalten könnten. Aufschlussreich sind zum einen die unterschiedlichen Prozesse einiger Staaten für die Entwicklung ihrer Strategie, u. a. Situationsanalysen, Stärken-Schwächen- und Chancen-Risiko-Analysen und öffentliche Konsultationsprozesse. Zum anderen kommen in den Strategien über regionale Grenzen hinweg Leitbilder, Begriffsbestimmungen, rechtliche Maßnahmen, technische und organisatorische Maßnahmen, Fachkräfte sowie Forschung und Entwicklung, nationale Partnerschaften und internationale Kooperation besonders häufig vor. Diese Themenschwerpunkte erfahren in den jeweiligen Ländern eine individuelle Regulierung, auf die an geeigneter Stelle exemplarisch Bezug genommen wird
Secondary products and bioactive compounds of Hermetia illucens: Extraction, chemical properties, and potential application of chitin and chitosan
No full text155188Chitin, the second most abundant biopolymer after cellulose, is a structural component of the exoskeleton of Hermetia illucens that can be employed for its extraction from the larval to the adult stage. Due to its poor solubility, chitin is converted into chitosan, its more soluble and versatile derivative. The main chemical extraction processes ensure biopolymers with purity and yields comparable to those from crustaceans, the industrial source, and from other insects, already studied in literature. Chitosan from H. illucens, solubilized in an acidic environment, has numerous biological characteristics, such as antimicrobial, antifungal, and antioxidant activities that make it a viable alternative to the commercial biopolymer. It can be applied in the agrifood sector to extend the shelf life of fresh products, as well as in biomedical and pharmaceutical fields. Dipteran-derived biopolymers are also used in nanometric form as carriers for the release of bioactive molecules
DIGITAL TWIN VALIDATION FOR THE IN-SITU AUTOMATED FIBER PLACEMENT PROCESS OF THERMOPLASTIC COMPOSITES
No full textThe digital twin is a methodology accelerating process knowledge for the automated fiber placement (AFP) of unidirectional thermoplastic tape with in-situ consolidation. It implies a continuous assessment and evaluation of data allowing a faster process optimization and reducing ramp-up times. In a previous study, a digital twin is developed allowing the interactive visualization of process data within a digital shadow and the interpretation of quality measures based on analytical methods. In this study, the developed digital twin for predicting the degree of bonding is validated by experimental results. By using destructive testing methods, such as interlaminar shear strength tests and microsections, the degree of bonding is quantified. The results are feedbacked to the initial digital twin forecast and a comparison is made. The results disclose the need to calibrate the analytical models as the underlying assumptions do not hold in a realistic environment. Based on these findings, a methodology is presented enabling a fast calibration of the analytical models. Aim is to reduce extensive experimental work for process optimization and, thus, to accelerate the ramp-up for a flexible series production
Human-machine collaboration on data annotation of images by semi-automatic labeling
No full text552556Deployment of deep neural network architectures in computer vision applications requires labeled images which human workers create in a manual, cumbersome process of drawing bounding boxes and segmentation masks. In this work, we propose an image labeling companion that supports human workers to label images faster and more efficiently. Our data-pipeline utilizes One-Shot, Few-Shot and pre-trained object detection models to provide bounding box suggestions, thereby reducing the required user interactions during labeling to corrective adjustments. The resulting labels are then used to continuously update the underlying suggestion models. Optionally, we apply a refinement step, where an available bounding box is converted into a finer segmentation mask. We evaluate our approach with a group of participants who label images using our tool - both manually and with the system. In all our experiments, the achieved quality is consistently comparable with manually created labels at factor 2 to 6 faster execution times
Analysis of the Impact of Environmental Conditions on the Reliability in 5G PCB Assemblies
No full textThe designs of integrated systems are increasingly compact while the requirements of application, especially in the automotive sector, remain demanding. One main challenge is posed by the environmental conditions. In the present study, their impact on mmWave 5G PCB assemblies is evaluated with respect to both mechanical and high-frequency properties. To that end, material samples were stored at three temperatures for various durations in order to accelerate the ageing effects. Afterwards, the samples were tested by use of mechanical, dielectric and high- frequency test methods. Thermo-oxidative ageing processes were observed and lead to significant changes in mechanical and dielectric properties, with simultaneous changes of sample color. The combined approach of mechanical and high-frequency analysis allows for three innovative advantages: First, a correlation of the degradation in performance with other parameters, e.g. sample change of color, which is much easier to detect. Second, the definition of a Safe Area of Operation and a methodology to estimate the behaviour of a mmWave 5G PCB assembly over its lifetime. Finally, the study opens the pathway to a design for robustness of mmWave communication system in automotive applications
MEMS-Based Fingerprinting Architecture for Trustworthy Electronics
No full textA fingerprint architecture based on a micro electro mechanical system (MEMS) for the use as a hardware security component is presented. The MEMS serves as a physically unclonable function (PUF) and is used for fingerprint ID generation, derived from the MEMS-specific parameters. The fingerprint is intended to allow the unique identifiability of electronic components and thus to ensure protection against unauthorized replacement or manipulation. The MEMS chip consists of 16 individual varactors with continuously adjustable capacitance values that are used for bit derivation ('analog' PUF). The focus is on the design-related forcing of random technological spread to provide a wide range of different parameters per chip or wafer to achieve a maximum key length. Key generation and verification is carried out via fingerprint electronics connected to the MEMS, which is realized by an FPGA
The ISO/IEC 17025 accreditation journey for additive manufacturing in medical engineering
No full textOver the recent years, additive manufacturing has undergone rapid development towards industrial application, so that more and more products and components can be manufactured additively. However, since critical properties of printed parts are strongly influenced by complex interdependencies among process parameters, quality control is facing different challenges as with other, more traditional, means of fabrication. This opens a wide field of new needs for testing standards and procedures for the application and material specific manufacturing of parts, especially in the highly regulated domain of medical engineering. In order to address this need, we have set up a testing laboratory for additively manufactured parts (metals and polymers) according to ISO/IEC 17025, which has its accreditation certificate by the German accreditation body (DAkkS) since the end of February 2025. The particular challenge for research in the section of medical engineering is to integrate the regulatory requirements right into the development of new devices, to avoid additional development loops. Therefore, a quality management system, to be applied in the testing laboratory as defined by ISO/IEC 17025, had to be implemented. In addition, the necessary operating and work instructions were defined for the testing procedures of geometrical and defect analysis, both based on high resolution (for small parts up to 150nm) computed tomography. This includes the development of a supporting document that covers the entire testing process from the customer inquiry to the submission of the test report, ensuring that every testing laboratory employee can be sure that they have completed all steps of the testing process. Among other things, it is now possible to 3D print circuit boards, where special care must be taken, to ensure that the conductor tracks are not interrupted by printing errors. This is an example for the development of new testing methods and quality standards, that can be realized within the testing laboratory, to address the specific requirements of additively manufactured medical devices that has not yet been defined in detail. We share the experience,, which we have gained through the implementation so far, with the community.7S
Pressure Pulse Classification for Flow Disturbance Detection in Micro Diaphragm Pumps
No full text636639Micropumps have the potential to complement or even replace infusion pumps used in hospital and home care environments. For safe and reliable operation, error detection must be available for these devices. In this work we present a machine learning based approach that classifies pressure pulses created by a micropump into several operation states (normal operation, air-in-line, upstream- and downstream occlusion). An automated setup to generate these flow states and to automatically read and label the corresponding pressure pulse sensor data was built. Using this setup, a dataset consisting of 12.000 pressure pulses from five micropumps was recorded. Characteristic statistical features for the four flow states were extracted from this dataset using TSfresh. Using these statistical features, a decision tree model was trained. The model achieved a classification accuracy of 93%
Grid Forming Converters in Interconnected Systems - Final Results from the Joint Research Project VerbundnetzStabil
No full text135140When integrating grid forming converters (GFC) into the power system, it is not just a matter of replacing the converter's current controller with a voltage controller; all aspects of power system dynamics have to be considered in order to design a suitable behavior of GFC. This is necessary in order to fully replace the grid forming and grid stabilizing properties of synchronous generators with converters. Within the joint research project VerbundnetzStabil the partners KACO new energy, TransnetBW, University of Stuttgart and Fraunhofer ISE investigated the stability of interconnected power systems with a high penetration of converters over the past four years. This paper summarizes the work of the project team and their major findings. Keywords— grid forming converters; converter control; power system stability; converter based generatio
Manufacturing of Net-Shape and Wear-Resistant Composite Components via the Combination of Additive Manufacturing and Hot Isostatic Pressing
No full text7884Additive Manufacturing (AM) is an emerging technology with increasing importance in scientific and industrial applications. It is suitable for the manufacturing of very complex components straight from CAD data. Furthermore, it can complement powder metallurgical (PM) Hot Isostatic Pressing (HIP) when it is used to produce geometrical complex capsules, opposed to the manual fabrication by welding of sheet metal. This combined process route is highly automatable and can even be further enhanced when it is accompanied by numerical simulations in the design process of the near-net-shape capsules. Due to design optimization, there is no need to remove the capsule and it becomes an integral and functional part of the component. When the capsule is produced e.g., from wear-resistant materials, it can form a wear-resistant outer layer. This study comprises the manufacturing of net-shape and wear-resistant HIP capsules from the carbide rich cold working tool steel AISI A11 (X245VCrMo10-5-1) via Powder Bed Fusion – Electron Beam (PBF-EB). The capsules are filled with the tough Q+T steel AISI L6 (56NiCrMoV7) and densified by HIP with an integrated heat treatment. The focus is on the validation of the simulation, microstructural analysis, as well as analysis of the wear-resistance