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Deep learning-based localisation of combine harvester components in thermal images
No full text7182It is crucial to identify defective machine components in production to ensure quality. Some components generate heat when defective, so automating the inspection process with a thermal imaging camera can provide qualitative measurements. This work aims to use computer vision methods to locate these components in thermal images. Since there is currently no comparison of object detection and semantic segmentation algorithms for this use case, this study compares different architectures with the goal of localising these components for further defect inspection. Moreover, as there are currently no datasets for this use case, this study contributes a novel annotated dataset of thermal images of combine harvester components. The different algorithms are evaluated based on the quality of their predictions and their suitability for further defect inspection. As semantic segmentation and object detection cannot be directly compared with each other, custom weighted metrics are used. The architectures evaluated include RetinaNet, YOLOV8 Detector, DeepLabV3+, and SegFormer. Based on the experimental results, semantic segmentation outperforms object detection regarding the use case, and the SegFormer architecture achieves the best results with a weighted MeanIOU of 0.853
Evaporation reduction and energy generation potential using floating photovoltaic power plants on the Aswan High Dam Reservoir
No full text709720There is an opportunity for efficient implementation of floating photovoltaics (FPV) by coupling with other renewable energies, such as hydropower. The resulting synergies benefit both technologies. Particularly in arid regions, hydropower reservoirs face considerable evaporation. As a benefit, FPV minimizes evaporation while simultaneously generating renewable energy. In this study, we simulate the evaporation reduction due to FPV by applying the hydrodynamic General Lake Model together with the yield simulation model Zenit to the Aswan High Dam Reservoir. We estimate a 49.7% evaporation reduction at 90% FPV occupancy and water savings of up to 5.9 billion m3 per year (BCM a−1). The mean specific water saving of the FPV system is 7.67 m3 a−1 kWp−1. We analyse possible ways to use the saved water, such as additional hydropower, filling up the Toshka Lakes, or agricultural irrigation. The use of FPV water savings for irrigation appeared to be most efficient.69
Rising against the odds: Key lessons for promoting female leaders’ resilience
No full textGiven the many obstacles women encounter on their path to leadership positions, resilience is particularly important for women in leadership. Nevertheless, there is still little knowledge about the specifics of female leader resilience and how it can be enhanced. Drawing on a qualitative interview study, we show how female leaders’ resilience can be promoted at individual, organizational, and societal levels. For this purpose, we conducted 48 in-depth semistructured interviews with female leaders from upper, middle, and lower leadership positions in various industrial sectors. We found that female leader resilience is shaped by individual internal resources (such as achievement orientation, self-confidence, and adaptability) and social support (such as a supportive partner, family, and friends), encouraged by enabling organizational factors (such as inclusive cultures, flexible structures, and mentoring), and influenced by societal factors (such as gender-specific role expectations, early socialization, and access to role models). We further demonstrate that due to persistent inequalities, stereotypes, and prejudices, women rely on their resilience not only in crisis situations but also in the context of everyday leadership. Thus, our study offers valuable insights for developing female leaders’ resilience in both theory and practice.Online Firs
Evaluation of Mechanical and Surface Integrities in Cemented Carbides Processed by Femtosecond Laser Machining and Physical Vapor Deposition-Coating
No full textLasers are widely applied in modern industries, ranging from subtractive machining to additive manufacturing. Pulsed laser technology has significantly advanced precision machining, particularly for hard or refractory materials that are challenging to process using conventional methods. Cemented carbides exemplify such materials, serving as essential components in cutting tools and wear-resistant parts. In practice, these carbides are frequently coated to enhance wear resistance and extend service life. Previous studies show that nanosecond lasers could improve the performance of coated cemented carbides but induce microscale thermal side effects. Femtosecond lasers can minimize these effects, reducing issues like melting and pore formation. This study examines the surface and mechanical integrity of femtosecond laser-machined cemented carbides with subsequent physical vapor deposition coating. Vickers hardness, micro-scratch testing, and post-scratch topographical analysis were applied to evaluate coating performance and surface integrity. Results show that femtosecond laser processing minimally affects surface integrity, inducing only slight changes in morphology (roughness) and microstructure. The laser-induced modification of surface roughness may contribute to improved coating adhesion, while localized carbide enrichment associated with selective binder removal could further reinforce the near-surface region. These effects help explain the enhanced mechanical performance observed for the coated cemented carbides. In particular, low-energy laser processing, especially when sliding perpendicular to the laser-induced features, further enhances coating performance.148
Quality of life measurement in assessing treatment effectiveness in urticaria: European experts position statement
No full text16571667In this study, the European Academy of Dermatology and Venereology (EADV) Task Forces on Quality of Life and Patient-Oriented Outcomes and Urticaria and Angioedema has examined the Health-Related Quality of Life (HRQoL) measurement in the treatment of urticaria. The Dermatology Life Quality Index was the most frequently used HRQoL instrument in clinical trials on urticaria. Many reports of clinical trials of urticaria gave no exact numeric results related to HRQoL changes, making clear conclusions and comparisons with other studies impossible. The interpretation of HRQoL impairment data is more difficult when assessed by instruments without severity stratification systems. The minimal clinically significant difference (MCID) is a more clinically oriented and relevant parameter than depending on statistically significant changes in HRQoL scores. Therefore, using HRQoL instruments with established MCID data in clinical trials and clinical practice is preferred.631
X-maps: Direct Depth Lookup for Event-based Structured Light Systems
No full text40074015We present a new approach to direct depth estimation for Spatial Augmented Reality (SAR) applications using event cameras. These dynamic vision sensors are a great fit to be paired with laser projectors for depth estimation in a structured light approach. Our key contributions involve a conversion of the projector time map into a rectified X-map, capturing x-axis correspondences for incoming events and enabling direct disparity lookup without any additional search. Compared to previous implementations, this significantly simplifies depth estimation, making it more efficient, while the accuracy is similar to the time map-based process. Moreover, we compensate non-linear temporal behavior of cheap laser projectors by a simple time map calibration, resulting in improved performance and increased depth estimation accuracy. Since depth estimation is executed by two lookups only, it can be executed almost instantly (less than 3 ms per frame with a Python implementation) for incoming events. This allows for real-time interactivity and responsiveness, which makes our approach especially suitable for SAR experiences where low latency, high frame rates and direct feedback are crucial. We present valuable insights gained into data transformed into X-maps and evaluate our depth from disparity estimation against the state of the art time map-based results. Additional results and code are available on the X-maps project page
Venture Clienting in Corporate Practice: What Type of Established Companies are Using the Venture Client Model?
No full text225235Start-ups have become a pillar of EC' open innovation initiatives. With the aim of accessing start-up innovation, established companies (EC) use various corporate venturing modes. However, as established corporate venturing modes (e.g. corporate venture capital or accelerators) do not provide direct access to start-up innovation, the venture client model (VCLM) is receiving increasing attention in corporate practice. In the VCLM, ECs become paying customers of start-ups without taking equity - they become venture clients. In joint pilot projects, they apply start-up solutions to their products, processes or business models in order to solve relevant business problems and create strategic impact for increased competitiveness. The literature lists different EC using the VCLM such as BMW, Bosch, Continental, Daimler, Siemens, or ZF. This suggests that the VCLM is only used in EC with tens of thousands of employees, from Germany and in technology-intensive sectors such as automotive, mechanical engineering or telecommunications. On the other hand, GIMMY describes the suitability of the VCLM for any EC. However, in order to develop practical solutions to the challenges of the VCLM (e.g. slow purchasing, legal and IT processes or lack of acceptance of start-ups as collaboration partners), it is necessary to know the users (type of EC) of these solutions. Therefore, the aim of this paper is to characterize the EC using the VCLM with respect to industry, size and regionality
Intercore-gain-crosstalk in multicore fiber amplifiers for telecommunication applications
No full text3135Spatial division multiplexing is the only currently known technique to cope with the forecasted demand for capacity in the long term. Of particular interest is its implementation as multicore fiber system, which offers further capacity increase while simultaneously reducing cost and energy consumption per throughput. Essential components in such a transmission system are cladding pumped multicore amplifiers, which allow for signal amplification in multiple cores via a single uncooled multimode pump. However, above mentioned advantageous features could come with the detriment of a coupling of the pump powers available for amplification in the different cores. The resulting gain crosstalk is investigated by means of simulations for various signal power distribution schemes across the cores. In particular, gain variations in all cores are demonstrated to be negligible for signal power changes in other cores
Numerical model development and cutting force analysis for high-speed blanking of 22MnB5
No full textHigh-speed blanking (HSB) is an advanced cutting process particularly suitable for high-strength steels. Accurate and physically realistic simulation of this process can help to obtain basic understanding of the process mechanisms, but it is challenging due to the very high strain rates, the required thermo-mechanical coupling, and the necessity of representing the elastic characteristics and dynamic behaviour of the tools in the numerical model. Model validation is an added challenge due to the difficulty in accessing the key parameters from the highly dynamic process. In this study, we demonstrate the key aspects of the deforming material and the tool components to be accounted for in the numerical model, as well as the measurement of relevant process variables that can be used to build and validate a realistic process simulation. The validated simulations support interpretation of the experimental results with respect to measured cutting-force curves for two different tools. To describe the deformation behaviour of 22MnB5 under high-speed blanking conditions, the constitutive parameters of the Modified Johnson-Cook model are determined by inverse optimization in LS-OPT for strain rates of up to 3500 s-1. Tensile tests and Split Hopkinson Pressure Bar tests provided the experimental reference for model calibration. For the subsequent HSB process simulation, a three-dimensional LS-DYNA model was built, considering all tool components relevant to the load transmission path. All of these components were modelled as elastic bodies to account for the actual dynamic compliance of the system, which is essential for reproducing the measured time-dependent force. Good agreement between simulated and measured force–time histories demonstrates that accounting for elastic tool deformation in the 3D model is essential for realistic force prediction.1
Towards Wearable Continuous Point-of-Care Monitoring for Deep Vein Thrombosis of the Lower Limb
No full text326335Deep vein thrombosis (DVT) is the formation of a blood clot within the deep veins, most commonly those of the lower limbs, causing obstruction of blood flow. In 50% of people with DVT, the clot eventually breaks off and travels to the lung to cause pulmonary embolism. Clinical assessment of DVT is notoriously unreliable because up to 2/3 of DVT episodes are clinically silent and patients are symptom free even when pulmonary embolism has developed. Early diagnosis of DVT is crucial, and despite the progress made in ultrasound imaging and plethysmography techniques, there is a need for new methods to enable continuous monitoring of DVT at the point of care. This paper presents the conceptual design and methodology towards a novel wearable diagnostic device for point-of-care, operator-free, continuous monitoring in patients with high DVT risk. The device will combine novel wearable hardware for ultrasound imaging and impedance plethysmography with autonomous, AI driven DVT detection, to allow continuous monitoring for blood clot formation in the lower limb. Activity and other physiological measurements will be used to provide a continuous assessment of DVT risk and guide the automated scanning via an intelligent decision support unit that will provide accurate monitoring and alerts. The work is supported by the Horizon project ThrombUS+ co-funded by the European Union. (Grant Agreement No. 101137227)