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From nurse practitioner to nursing teacher
No full textAnhand von insgesamt 40 Interviews über den Studienverlauf des Studiengangs Pflegepädagogik hinweg, zeigt sich hinsichtlich des Selbstverständnisses eine zweigeteilte Entwicklung der Studierenden hinsichtlich des theoretischen und des praktischen Lernorts. Die Praxisbegleitung benötigt eine klare Profilstärkung, die curricular, pflegedidaktisch und gesetzlich verankert sein sollte, um eine effektive Zusammenarbeit an beiden Lernorten umzusetzen.On the basis of a total of 40 interviews over the course of the nursing education degree programme, a twofold development of the students' self-image with regard to the theoretical and practical learning location is evident. The task of practical placement visits requires a clear profile reinforcement, which should be anchored in the curriculum, nursing didactics and legislation in order to realise effective cooperation at both learning locations
Ride Parcel Pooling -- Nachhaltige Integration von Paketdiensten in Mobility on-Demand Systeme
No full textThis thesis addresses the pressing challenges of climate change, urbanization, e-commerce growth, and evolving urban mobility patterns, emphasizing the need for a comprehensive strategy to mitigate their environmental and societal impacts. It introduces Ride Parcel Pooling, an on-demand mobility service that integrates passenger ride-pooling and urban parcel transportation to deliver environmental, economic, and social benefits. Through thorough analysis, simulation, and real-world testing, the thesis demonstrates the feasibility and benefits of Ride Parcel Pooling.Die Dissertation befasst sich mit den drängenden Herausforderungen des Klimawandels, der Urbanisierung, des Wachstums des Online-Handels und der sich verändernden Mobilitätsbedürfnisse in Städten. Die Konzeptualisierung, Modellierung und Erprobung von Ride Parcel Pooling hat die Machbarkeit und die Vorteile eines integrierten on-demand Mobilitätssystems für Passagiere und Pakete aufgezeigt und seinen potenziellen Beitrag zu einer nachhaltigen urbanen Mobilität für Passagiere und Pakete demonstriert
A Robust Unified Strategy for Maximum Torque Per Ampere and Field Weakening in Permanent Magnet Synchronous Motor
No full textThe intricate control structure and demanding preparations undeniably make the high precision and performance realization of maximum torque per ampere (MTPA) and field weakening (FW) strategies challenging in the permanent magnet synchronous motor (PMSM). This paper proposes a straightforward yet potent strategy to surmount this challenge. By redefining the whole control process as a convex optimization and employing the indicator function to approximate constraints, the MTPA-FW control is seamlessly realized through the calculation of a single equation online, obviating the requirement for any supplementary operation. Meanwhile, a model correction method based on the moving horizon estimator is designed to mitigate the impact of parameter variation and enhance the calculation accuracy. The experimental results have proved the superiority of the proposed strategy
Improved accuracy of continuum surface flux models for metal additive manufacturing melt pool simulations
No full textComputational modeling of the melt pool dynamics in laser-based powder bed fusion metal additive manufacturing (PBF-LB/M) promises to shed light on fundamental mechanisms of defect generation. These processes are accompanied by rapid evaporation so that the evaporation-induced recoil pressure and cooling arise as major driving forces for fluid dynamics and temperature evolution. The magnitude of these interface fluxes depends exponentially on the melt pool surface temperature, which, therefore, has to be predicted with high accuracy. The present work utilizes a diffuse interface finite element model based on a continuum surface flux (CSF) description of interface fluxes to study dimensionally reduced thermal two-phase problems representative for PBF-LB/M in a finite element framework. It is demonstrated that the extreme temperature gradients combined with the high ratios of material properties between metal and ambient gas lead to significant errors in the interface temperatures and fluxes when classical CSF approaches, along with typical interface thicknesses and discretizations, are applied. It is expected that this finding is also relevant for other types of diffuse interface PBF-LB/M melt pool models. A novel parameter-scaled CSF approach is proposed, which is constructed to yield a smoother temperature field in the diffuse interface region, significantly increasing the solution accuracy. The interface thickness required to predict the temperature field with a given level of accuracy is less restrictive by at least one order of magnitude for the proposed parameter-scaled approach compared to classical CSF, drastically reducing computational costs. Finally, we showcase the general applicability of the parameter-scaled CSF to a 3D simulation of stationary laser melting of PBF-LB/M considering the fully coupled thermo-hydrodynamic multi-phase problem, including phase change
Effects of Higher-Fidelity Route Definition in Modeling Fleet Development Influenced by Airport Congestion
No full textChanges in urinary stable nitrogen isotope ratios during controlled short-term energy deficit: a proof-of-principle analysis
No full textPurpose: Stable isotope ratios of nitrogen (δ15N) have previously been shown to increase in human hair during periods of catabolism. The goal of this study was to assess changes in δ15N in urinary urea (δ15Nurea) and Δ15N during a short-term controlled energy deficit.
Methods: We analyzed samples from 6 recreationally active men (25 ± 1 years, BMI: 23.5 ± 0.6 kg/m2) who participated in a repeated measures cross-over study involving 4 days of energy deficit (ED, ~ 15 kcal/kg FFM) without and with exercise (ED-EX, ED + EX) and control conditions in energy balance (CON-EX, CON + EX). δ15Nurea was analyzed from urine samples, and Δ15N was calculated as δ15Nurea–δ15Ndiet, with δ15Ndiet obtained from diet prescriptions.
Results: δ15Nurea was significantly elevated in ED-EX (4.4 ± 0.2‰) when compared to CON-EX (3.7 ± 0.1‰; p = 0.026) and CON + EX (3.34 ± 0.13‰, p = 0.001). As a consequence, Δ15N was positive in ED-EX (0.2 ± 0.2‰) and remained negative in ED + EX (− 0.6 ± 0.5‰), CON-EX (− 1.0 ± 0.2) and CON + EX (− 1.1 ± 0.2). Differences in Δ15N were significant between ED-EX and CON-EX (p = 0.005) and ED-EX and CON + EX (p = 0.006).
Conclusion: Our results suggest that δ15Nurea and subsequently Δ15N are responsive to a short-term energy deficit, likely due to increased amino acid oxidation to meet energy demands and preferable elimination of 14N
Machine Learning Analysis of Human Skin by Optoacoustic Mesoscopy for Automated Extraction of Psoriasis and Aging Biomarkers.
No full textUltra-wideband raster-scan optoacoustic mesoscopy (RSOM) is a novel modality that has demonstrated unprecedented ability to visualize epidermal and dermal structures in-vivo. However, an automatic and quantitative analysis of three-dimensional RSOM datasets remains unexplored. In this work we present our framework: Deep Learning RSOM Analysis Pipeline (DeepRAP), to analyze and quantify morphological skin features recorded by RSOM and extract imaging biomarkers for disease characterization. DeepRAP uses a multi-network segmentation strategy based on convolutional neural networks with transfer learning. This strategy enabled the automatic recognition of skin layers and subsequent segmentation of dermal microvasculature with an accuracy equivalent to human assessment. DeepRAP was validated against manual segmentation on 25 psoriasis patients under treatment and our biomarker extraction was shown to characterize disease severity and progression well with a strong correlation to physician evaluation and histology. In a unique validation experiment, we applied DeepRAP in a time series sequence of occlusion-induced hyperemia from 10 healthy volunteers. We observe how the biomarkers decrease and recover during the occlusion and release process, demonstrating accurate performance and reproducibility of DeepRAP. Furthermore, we analyzed a cohort of 75 volunteers and defined a relationship between aging and microvascular features in-vivo. More precisely, this study revealed that fine microvascular features in the dermal layer have the strongest correlation to age. The ability of our newly developed framework to enable the rapid study of human skin morphology and microvasculature in-vivo promises to replace biopsy studies, increasing the translational potential of RSOM
