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Conversion of CIM CGMES data sets to the open source software pandapower – case study including an ENTSO-E test network
No full text479485The need for information and data exchange between multiple grid operators is more important than ever before. In Europe, the “Common Grid Model Exchange Standard” (CGMES) [1] by the “European Network of Transmission System Operators for Electricity” (ENTSO-E) is one of the standard data formats to exchange grid data. Even though CGMES is well defined, it allows for ambiguities, small variations of modelling and interpretation of different grid assets, which can result in errors and wrong power flow results since different applications might interpret the CGMES data differently. A direct intuitive interpretation and validation of CGMES data sets by humans or free available grid analysis tools is barely possible due to their storage in long Extensible Markup Language (XML) files. Thus, a conversion into a simpler, human-readable and open source format is required. In this work, the open source Python package “cim2pp” is introduced, for converting CGMES data sets into the open source grid format “pandapower”. The converter’s accuracy is shown by translating two benchmark data sets, including a reference grid model from ENTSO-E. Additional performance tests demonstrate that cim2pp converts large data sets to pandapower within acceptable computation times
First Characterization of Comb Drive Based Micro Mirror Arrays
No full text327331The demand for more advanced display technologies for virtual- and augmented reality requires new spatial light modulators (SLMs) to fulfil the requirements for fast and accurate phase modulation. Simulations of the developed comb drive design have shown its ability to meet these requirements. The first manufactured devices now proof that the approach of ultra-high-density integration of several million pixels, each only a few µm in size, can lead to the desired goal: a micro mirror array (MMA) based SLM that enables real time holographic imaging
Fabrication of Sustainable 3D Printed Anisotropic Bonded Magnets Using Recycled Nd-Fe-B Powder and Low CO2 Footprint Polyamide 12
No full textPolymer-bonded Nd-Fe-B magnets, made from hard magnetic powder and a polymer binder, are essential in many high-tech applications. The growing demand in energy-conversion devices calls for a more circular and versatile approach to their production. This study presents a sustainable approach to fabricate anisotropic polymer-bonded Nd-Fe-B magnets using recycled powder from end-of-life (EOL) hot-deformed magnets. Employing laser powder bed fusion with a low CO2 footprint polyamide 12 matrix in combination with magnetic powder enables production of complex geometries. Two methods are compared for converting EOL hot-deformed magnets into powder and the resulting performance of printed bonded magnets with these powders. Both powders have an elongated shape with the magnetic easy axis oriented perpendicular to the particle's length. Utilizing these anisotropic powders, based on a previously studied alignment mechanism, anisotropic bonded magnets are fabricated with over 60% higher magnetic performance compared to those made from EOL sintered magnet powders in 3D printing. The fabricated magnets have a remanence of 0.34 T and coercivity of 1238 kA m-1. The findings demonstrate a pathway toward turning parts of the magnet market into a more circular economy by reducing reliance on primary Nd-Fe-B sources and enhancing efficiency of magnetic powder use.7
Development of 3D printed patient-specific skull implants based on 3d surface scans
No full textSometimes cranioplasty is necessary to reconstruct skull bone defects after a neurosurgical operation. If an autologous bone is unavailable, alloplastic materials are used. The standard technical approach for the fabrication of cranial implants is based on 3D imaging by computed tomography using the defect and the contralateral site. A new approach uses 3D surface scans, which accurately replicate the curvature of the removed bone flap. For this purpose, the removed bone flap is scanned intraoperatively and digitized accordingly. When using a design procedure developed for this purpose creating a patient-specific implant for each bone flap shape in short time is possible. The designed skull implants have complex free-form surfaces analogous to the curvature of the skull, which is why additive manufacturing is the ideal manufacturing technology here. In this study, we will describe the intraoperative procedure for the acquisition of scanned data and its further processing up to the creation of the implant.9
Integration of Scaled Real-world Testbeds with Digital Twins for Future AI-Enabled 6G Networks
No full text20372042Future 6G communication systems need to be carefully evaluated under near real-life boundary conditions to prove their performance beyond theoretical considerations and simulations. In this work, we propose a new, lean approach to integrate and evaluate future 6G network architectures and AI-enabled approaches in scaled physical environments that emulate the full-scale communication, mobility, and environmental conditions powered by a Digital Network Twin (DNT). Our approach is enabled by the realistic modeling of the radio environmental impacts within the DNT, such as path loss, shadowing, and interference. One key contribution lies in the specific communication emulation functionality embedded in the real-time capable DNT, which allows imposing specific communication technology properties of the real-life scenario on the scaled physical environment. In this paper, we introduce a prototyping architecture and present a comprehensive case study to demonstrate the effectiveness of the approach: the AI-enabled mesh routing protocol PARRoT is evaluated in three scaled scenarios (teleoperation, platooning, and intralogistic transport). The results show that future 6G networks can be evaluated in realistic, yet safe and cost-efficient environments before moving onto the real world
A Numerical Modeling Tool for Scanning Air-Coupled Ultrasonic Testing Based on the Elastodynamic Finite Integration Technique (EFIT)
No full textIn this article, a numerical simulation tool for the calculation and optimization of scanning air-coupled ultrasonic testing (ACUT) of nearly arbitrary multilayer structures with and without flaws based on the elastodynamic finite integration technique (EFIT) is presented. It includes 2-D and 3-D solvers for flat and curved isotropic and anisotropic layered structures in transmission, pulse-echo, and pitch-catch configuration. During the development, special attention was paid to the minimization of computing time in the scanning mode, which was achieved by various measures. The paper presents the freely configurable parameters of the EFIT solver, typical result output, special features, and an optional LabVIEW-based user interface. Along the way, several simulation examples from air-coupled ultrasonic testing are demonstrated
Demonstration of wafer-level integrated permanent bias micromagnets for magnetic field sensors
No full text452456For the demonstration of magnetic biasing with wafer-level integrated permanent magnets, a Hall sensor is equipped with a back bias magnet by directly integrating the magnet into the silicon substrate. For this purpose, a powder-based micro-fabrication technique, called PowderMEMS, is utilized. The plausibility of the approach to equip magnetic sensors with substrate-integrated bias magnets is investigated by simulation and measurement of the rotation of a soft magnetic gear wheel, representing a typical biased sensor application. In addition, shaping of the magnetic field distribution using customized magnet geometries is performed and investigated
How do institutional conditions influence research use by policy makers?
No full textEffective use of research in policy making is essential to address persistent societal challenges and respond to emerging issues. While much is known about individual preferences and practices of policy-maker research use, the structuring role of institutionalised influences remains less understood. This article addresses that gap by examining how institutional conditions shape research use in policy making, drawing on survey data from 1,606 respondents in Norwegian ministries and directorates. We analyse policy makers’ perceptions of four types of institutional conditions – formal instruction, financial and infrastructural support, peer environment, and informal encouragement - and their relationship to instrumental, conceptual and symbolic uses of research. The findings show that encouraging institutional conditions are stronger determinants of research use than enabling ones, and that the distinction between formal and informal conditions matters. Formal instruction is associated with conceptual use, supporting long-term reflection and planning, while informal encouragement is more strongly linked to instrumental use in short-term, time-constrained policy tasks.Online Firs
Scan path resolved thermal modelling of LPBF
No full textLaser powder bed fusion product quality depends on process parameters (e.g. laser power, scan speed, etc.) and on the scan strategy. The accuracy by which a feature outline is printed defines the surface finish, workpiece fatigue behavior and the extent of post processing needed to achieve surface quality specifications. In this paper we develop a semi-analytic thermal model allowing the resolution of the scan strategy in detail while solving the energy equation to predict the thermal history of the printed component and its features. Experiments are performed using process parameters that have been shown to achieve an IN718 relative density larger than 99.5%. We study the influence of scan strategies on different features’ surface quality while keeping the process parameters unchanged. The model is driven by the build file provided to the 3D printer or using the more accurate in-situ process data describing the laser path and status. The model is verified using high-fidelity models as well as experimental results. We demonstrate both experimentally and numerically how the printer controller changes the build strategy, slightly affecting the quality of fine features. Laser scan dynamics and timing, particularly sky-writing, was shown to have a critical effect on the melt pool morphology and necessary to include in the models.