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Pulmonary response prediction through personalized basis functions in a virtual patient model
(2024)
Effiziente Erosion von superabrasiven Werkzeugen : Schwerpunkt auf Schleif- und Abrichtwerkzeugen
(2024)
Ein stationsspezifisches Lärmmanagement auf drei Intensivstationen des Universitätsklinikums Freiburg sollte Pflegefachpersonen im Umgang mit Lärm sensibilisieren, um diesen nachhaltig zu reduzieren. Das eigens dafür entwickelte Projekt „Stille Intensivstation“ hat sich auch mit dem Lärmerleben von Patienten und Angehörigen befasst.
As machine learning becomes increasingly pervasive, its resource demands and financial implications escalate, necessitating energy and cost optimisations to meet stakeholder demands. Quality metrics for predictive machine learning models are abundant, but efficiency metrics remain rare. We propose a framework for efficiency metrics, that enables the comparison of distinct efficiency types. A quality-focused efficiency metric is introduced that considers resource consumption, computational effort, and runtime in addition to prediction quality. The metric has been successfully tested for usability, plausibility, and compensation for dataset size and host performance. This framework enables informed decisions to be made about the use and design of machine learning in an environmentally responsible and cost-effective manner.
This chapter introduces the technology Non-Intrusive Load Monitoring, a method for detecting individual devices from an overall signal. Non-Intrusive Load Monitoring is the research area and technology behind the third word in Smart Meter Inclusive. Using a smart meter as a basis and recognizing devices from the power profile is not a new idea but is now a common practice in Non-Intrusive Load Monitoring. However, the approach to creating such a measurement system that classifies appliances in real-time and visualizes the results directly on the same hardware has not been existing yet. Smart Meter Inclusive wants to leave the data where it originates, namely with the customer. This book chapter provides a general overview of non-intrusive load monitoring to be able to understand the basics and approaches for such a Smart Meter Inclusive.
In this paper, the influence of current sensors of a NILM system is investigated. The current sensors of a classical inductive current transformer and a Rogowski coil are compared. To evaluate the actual influence on the NILM, measurements are performed with two measuring systems with different current sensors. With these measuring systems, 20 different consumers with 50 switch-on and switch-off cycles are measured in parallel. Besides, the influence of the sampling rate on the results of the NILM classification is evaluated. The classification is carried out with features normalized to the performance and without phase information, so only the signal waveform is used to differentiate the devices.
Elevators contribute significantly to the electricity consumption of residential buildings, office buildings and commercial enterprises. In this paper, the electricity consumption is investigated using an elevator system and its individual operating states as example. In addition to analyzing and allocating the energy demand, this work examines how the individual operating states can be determined solely on the basis of the power consumption of the elevator. The knowledge gained from this, such as the usage behavior, the travel profile, or load, is determined independently of the elevator control system. A subsequent installation on any system can be easily realized. In this work, the investigated elevator requires a substantial part of the total annual power consumption in standby (>90 %). This shows an enormous potential for energy savings. The individual elevator states, as well as the load, can be detected very well on the basis of the measured total power consumption. The work thus shows exemplary the potential of an intelligent measurement system for the state detection of elevator systems.
Introduction: The present study investigated the role of training intensity in the dose–response relationship between endurance training and cardiorespiratory fitness (CRF). The hypothesis was that beginners would benefit from an increase in training intensity after an initial training phase, even if the energy expenditure was not altered. For this purpose, 26 weeks of continuous moderate training (control group, CON) was compared to training with gradually increasing intensity (intervention group, INC) but constant energy expenditure.
Methods: Thirty-one healthy, untrained subjects (13 men, 18 women; 46±8 years; body mass index 25.4 ± 3.3 kg m−2; maximum oxygen uptake, VO2max −1 −1 34 ± 4 ml min kg ) trained for 10 weeks with moderate intensity [3 days/week for 50 min/session at 55% heart rate reserve (HRreserve)] before allocation to one of two groups. A minimization technique was used to ensure homogeneous groups. While group CON continued with moderate intensity for 16 weeks, the INC group trained at 70% HRreserve for 8weeks and thereafter participated in a 4 × 4 training program (high-intensity interval training, HIIT) for 8 weeks. Constant energy expenditure was ensured by indirect calorimetry and corresponding adjustment of the training volume. Treadmill tests were performed at baseline and after 10, 18, and 26 weeks.
Results: The INC group showed improved VO2max (3.4 ± 2.7 ml kg−1 min−1) to a significantly greater degree than the CON group (0.4 ± 2.9 ml kg−1 min−1) (P = 0.020). In addition, the INC group exhibited improved Vmax (1.7 ± 0.7 km h−1) to a significantly greater degree than the CON group (1.0 ± 0.5 km h−1) (P = 0.001). The reduction of resting HR was significantly larger in the INC group (7±4bpm) than in the CON group (2±6bpm) (P=0.001). The mean heart rate in the submaximal exercise test was reduced significantly in the CON group (5±6bpm; P=0.007) and in the INC group (8±7bpm; P=0.001), without a significant interaction between group and time point.
Data processed in context is more meaningful, easier to understand and has higher information content, hence it derives its semantic meaning from the surrounding context. Even in the field of acoustic signal processing. In this work, a Deep Learning based approach using Ensemble Neural Networks to integrate context into a learning system is presented. For this purpose, different use cases are considered and the method is demonstrated using acoustic signal processing of machine sound data for valves, pumps and slide rails. Mel-spectrograms are used to train convolutional neural networks in order to analyse acoustic data using image processing techniques.
Separation of ventilation and cardiac activity on recorded voltages before EIT image reconstruction
(2023)
Modelability of processes is a recognized and important characteristic of any modeling language. Nevertheless, it is not always purposeful or easy to create process models for every kind of workflow. This article discusses the opportunities and limitations of modeling agile development projects with SCRUM as an example. For this purpose, a BPMN and an S-BPM model for SCRUM are presented. The discussion along recognized rules for good process models shows that both notations provide possible and accurate insights into the process of SCRUM on the one hand. On the other hand, the models raise questions of necessity, added value, and relevance in practice. Practitioners can use the developed models to technically implement agile project management, while researchers benefit from a discourse on opportunities and limitations of modeling agility.
For many practitioners, considering sustainability during a software development project is a challenge. The Sustainability Awareness Framework (SusAF) is a tool for thinking through short, medium-and long-term impacts of socio-technical systems on its surrounding environment. While SusAF has been used by several companies, is not widely adopted in industry yet. In this Vision Paper, we discuss the options for extending the reach of SusAF and what it would take to evolve SusAF into a (de-facto) standard
Digital transformation is now reaching into topics like End-of-life Care, Funeral Culture, and Coping with Grief. Those developments are inevitably accompanied by the growing challenge to design IT systems that are appropriate and helpful for the stakeholders involved. Our aim in this paper is to further introduce the rather new combined research field of Socioinformatics and Thanatology (the scientific study of death and dying) and to present it with the first results on which requirements to consider for the design of digital tools within ‘Thanatopractice’. By using Participatory Design and the Sustainability Awareness Framework (SusAF) in the context of three workshops on socio-technical systems (Online Pastoral Care, Virtual Graveyards, and AI Memory Avatars), we want to sensitize software practitioners to the multidimensional impacts of their products and services in a field, which the participants in the workshops often described as “highly sensitive”.
On Consistency Viability and Admissibility in Constrained Ensemble and Hierarchical Control Systems
(2023)
Several control architectures, such as decentralized, distributed, and hierarchical control, have been elaborated over the past decades for controlling systems composed of a set of subsystems. However, computational complexity and constraint satisfaction are still challenging tasks. We present an approach to control an ensemble of similar heterogeneous systems with input and state constraints via an identical control input. This control input is globally admissible and computed based on an aggregated system that reflects the overall behavior of the ensemble. To limit the computational complexity of the control task, the aggregated system is designed such that its dimension is independent of the number of subsystems. To guarantee viability, i.e., state constraint satisfaction for all times, appropriate consistency conditions are derived based on invariant set theory. The presented approach is illustrated with a numerical example.
In this paper, we derive set constraints for a reduced order model and augment them into a model predictive control (MPC) scheme to ensure safe operation of the large-scale ensemble system. For the control feedback, only the aggregated information of the whole system is required. For the constraint satisfaction, we consider an adaptive tube formulation to characterize the deviation between the reduced order model and the ensemble system. Employing the robust control invariant set, we ensure recursive feasibility and initial feasibility under an easily verifiable condition.
Im Zuge einer kritischen Diskussion dieses Beitrags ist anzumerken, dass – um eine wissenschaftlich fundierte und abschließende Beantwortung der Frage im Titel zu erarbeiten – mehr Quellen begutachtet und methodisch miteinander abgeglichen werden müssten. Jedoch eröffnet der Beitrag neue Einsichten, z.B. durch die Statements der klugen Köpfe, die Einbindung von Hebammen in technische Projekte oder eine möglichen Sicht des Fußballs auf das Thema »Thinking outside the box«.
Gemeinsam ist den verschiedenen Sichtweisen und Quellen jedoch der Appell, den Kopf oben zu be halten, über den Tellerrand zu schauen und sich um ein offenes Mindset sowie eine kreative Weiterentwicklung zu bemühen. Diese Philosophie ist besonders in Deutschland notwendig, denkt man an die Bedeutung von Innovationen, die geringen Innovationswahrscheinlichkeiten oder an die Problematik der Sprunginnovationen (vgl. Puddig 2019).
Eine weitere wichtige Kernbotschaft offeriert die Transformation von »Thinking outside the box« auf die Aktivitäten nach einer frühen Produktentwicklung: sich als Produktentwickler zuerst auf das Problem und nicht auf die Lösungen zu konzentrieren, in Features – Funktionen– Wirkprinzipien zu denken, Frontloading zu nutzen, Systeme und Domänen untereinander abzustimmen, auch das Service-Business dort bereits festzulegen, schnelle und einfache Prototypen zu bauen, nachhaltige Ansätze schrittweise zu implementieren, fertigungsgerecht zu konstruieren, sich des Werkzeugkastens mit agilen und traditionellen Werkzeugen bewusst zu sein und auch frühes Scheitern zu akzeptieren. Damit sind jedoch nur einige Aktivitäten genannt. Ob diese Empfehlungen aufgrund der schieren Komplexität ohne Assistenzsysteme umsetzbar sind, wird die Zukunft zeigen.
Obwohl alle aufgeführten Themen keine unbekannten sind, tut sich die Industrie mit der Umsetzung doch schwer. Darum ist es dem Autor ein Anliegen, dafür zu sensibilisieren und zu werben sowie die Forschung, wie sich eine erfolgreiche Transformation in die Industrie gestalten könnte, voranzutreiben. Zum gemeinsamen Forschen sowie zu einer offenen und kritischen Diskussion sind alle Interessierten herzlich eingeladen.