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In today's ultra-connected world, the significance of audio-visual documentation is rapidly growing. Technological advancements have made it more accessible to obtain powerful and compact audio-visual equipment, thereby reducing the dependency on a larger team for the documentation process. This has favoured the development of what is known as backpack journalism.
This project meets an unmet market need and presents an opportunity for innovative product development. It focuses on backpack journalists working in remote and challenging conditions with unpredictable transportation and working conditions. The proposed backpack design addresses both transport and working setups. Offering a robust and waterproof yet overall lightweight construction for easy equipment carrying, while also providing an extension of the workspace for essential gear.
Eine Sensorvorrichtung (10;110;210;310;410) zur Erfassung eines Magnetfelds, mit einer Wiegand-Sensoreinheit (12;112;212) umfassend: • - mindestens zwei Wiegand-Drähte (20) und • - eine Spulenanordnung (22;122;222), die die mindestens zwei Wiegand-Drähte (20) radial umschließt und die • • • ein Sensorelement (26;126;226) und • • ein Triggerelement (28;128;228), durch das ein Triggermagnetfeld erzeugbar ist, bildet, ist bekannt. Um ein magnetbasiertes Sensorsystem (300;400) zur Erfassung einer Bewegung eines beweglichen Objekts (301;401) zu ermöglichen, das ohne externe Energieversorgung zuverlässig sowie energieeffizient arbeitet und kostengünstig hergestellt werden kann, ist bei der erfindungsgemäßen Sensorvorrichtung (10;110;210;310;410) eine Wiegand-Triggereinheit (14;14a) vorhanden, umfassend: • - einen Wiegand-Draht (30) und • - eine Trigger-Sensorspule (32), die den Wiegand-Draht (30) radial umschließt, wobei ein erstes Ende der Trigger-Sensorspule (32) der Wiegand-Triggereinheit (14;14a) mit einem ersten Ende des Triggerelements (28;128;228) der Wiegand-Sensoreinheit (12;112;212) elektrisch verbunden ist und ein zweites Ende der Trigger-Sensorspule (32) der Wiegand-Triggereinheit (14;14a) mit einem zweiten Ende des Triggerelements (28;128;228) der Wiegand-Sensoreinheit (12;112;212) elektrisch verbunden ist. Auf diese Weise verstärkt ein in der Trigger-Sensorspule (32) erzeugter Impuls das Gesamtmagnetfeld, das auf die Wiegand-Drähte (20) in der Sensoreinheit einwirkt, derart, dass die Triggefeldstärke aller Wiegand-Drähte (20) überschritten wird und diese im wesentlichen zeitgleich auslösen.
Durch das WEMoG (Gesetz v. 16.10.2020, BGBl. I 2187) hat der Gesetzgeber die Regelung des § 20 WEG eingeführt. Demnach ist auch für bauliche Veränderungen an Räumen und Flächen, die einem Sondernutzungsrecht unterliegen, die Zustimmung der Gemeinschaft notwendig. Der BGH hat nun mit Urt. v. 17.3.2023 –V ZR 140/22, MDR 2023, 619 deutlich gemacht, dass bei Fehlen eines entsprechenden Beschlusses, die bauliche Veränderung durch einen einzelnen Wohnungseigentümer nicht vorgenommen werden darf, sondern eine rechtswidrige Eigentumsbeeinträchtigung darstellt. Der folgende Beitrag nimmt die Entscheidung zum Anlass, um die neue Rechtslage durch § 20 WEG eingehend zu erläutern. Gleichzeitig werden die Folgen der aktuellen Entscheidung näher dargestellt.
Das modulare Regalsystem „MORÉ“ ist ein Stauraummöbel, welches sich im Bereich des (Home) Office einordnet. Das Produkt dient zur Aufbewahrung von Büromaterialien und verbessert die Geräuschkulisse sowie die Beschaffenheit am Arbeitsplatz. Die potenzielle Käufergruppe befindet sich im Alter von 25-67 Jahren, im gewöhnlichen Arbeitsalter Zeitraum (obere Mittelschicht). Im Fokus des Regalsystems steht der besonders freundliche Auf- und Abbau, welcher werkzeuglos erfolgt. Es ist in verschiedene Richtungen erweiterbar (Steckverbindung) und bietet unendlichen Spielraum der Gestaltung. Durch verschiedenfarbige Kennzeichnungen bietet das Regal ein Ordnungssystem, wodurch schnelleres Finden und Sortieren von Unterlagen möglich ist (Grundordnung). Die Rückwände dienen neben der Stabilität als Akustik-/ und Sichtschutz. Das Produkt passt sich jeder Raumsituation individuell an. Ist „MORÉ“ dein nächstes Regalsystem?
Pendelleuchte aus Glas
(2023)
Glas ist seit jeher ein faszinierender Werkstoff. Es findet Anwendung in zahlreichen Gebieten und bietet als Material für Leuchten eine besondere Eleganz. Die Pendelleuchte „Calice di fiori“ vereint handwerkliche Kunstfertigkeit und komfortables Design. Sie ist aus mundgeblasenem Glas gefertigt und verleiht durch ihre Färbung eine kraftvolle und dynamische Atmosphäre im Raum. Das besondere Merkmal der Pendelleuchte ist eine Öffnung, die eine einfache und intuitive Montage erleichtert. Die Pendelleuchte ist mit energieeffizienten LEDs ausgestattet und lässt sich mit einem Smart-Home-System bedienen. Die Lichtintensität und Lichtfarbe können den individuellen Bedürfnissen angepasst werden. „Calice di fiori“ mit schnell abnehmbarem Leuchtenschirm fügt sich in modern eingerichtete Räume ein und bringt einen Hauch Blütenflair mit sich.
Der heutige Alltag vieler Menschen ist durch längere Sitz-Einheiten gekennzeichnet, während die körperliche Bewegung vernachlässigt wird. Diese Entwicklung kann einen negativen Einfluss auf die Haltung von Personen und ihre Gesundheit haben. In diesem Fall ist eine korrekte Haltung nicht nur für die körperliche, sondern auch für die psychische Gesundheit von großer Relevanz. Die Bachelorarbeit „LittleHabit“ ermöglicht es, dass bei Kindern die Bewegung nach langen Sitz-Einheiten durch gezieltes Training zur Gewohnheit wird. Hierbei wird zwischen dem Zuhause- und dem Schulbereich differenziert. Zu Hause soll das Kind beim Erledigen der Hausaufgaben durch Animationen und Lichtsignale dazu motiviert werden, Bewegungspausen einzulegen. In der Schule soll dieses Vorhaben in reduzierter Form aufgegriffen und mithilfe von Licht- und Farbsignalen umgesetzt werden. Darüber hinaus fördert es die intrinsische Motivation, sodass Kinder aus eigenem Antrieb ein Interesse dafür entwickeln, sich nach langen Sitz-Einheiten zu bewegen. LittleHabit setzt einen Baustein für die Entwicklung einer gesunden Sitz-Haltung und zielt darauf ab, Haltungsschwächen zu verhindern.
Traditional vulcanization mold manufacturing is complex, costly, and under pressure due to shorter product lifecycles and diverse variations. Additive manufacturing using Fused Filament Fabrication and high-performance polymers like PEEK offer a promising future in this industry. This study assesses the compressive strength of various infill structures (honeycomb, grid, triangle, cubic, and gyroid) when considering two distinct build directions (Z, XY) to enhance PEEK’s economic and resource efficiency in rapid tooling. A comparison with PETG samples shows the behavior of the infill strategies. Additionally, a proof of concept illustrates the application of a PEEK mold in vulcanization. A peak compressive strength of 135.6 MPa was attained in specimens that were 100% solid and subjected to thermal post-treatment. This corresponds to a 20% strength improvement in the Z direction. In terms of time and mechanical properties, the anisotropic grid and isotropic cubic infill have emerged for use in rapid tooling. Furthermore, the study highlights that reducing the layer thickness from 0.15 mm to 0.1 mm can result in a 15% strength increase. The study unveils the successful utilization of a room-temperature FFF-printed PEEK mold in vulcanization injection molding. The parameters and infill strategies identified in this research enable the resource-efficient FFF printing of PEEK without compromising its strength properties. Using PEEK in rapid tooling allows a cost reduction of up to 70% in tool production.
Manufacturing companies across multiple industries face an increasingly dynamic and unpredictable environment. This development can be seen on both the market and supply side. To respond to these challenges, manufacturing companies must implement smart manufacturing systems and become more flexible and agile. The flexibility in operational planning regarding the scheduling and sequencing of customer orders needs to be increased and new structures must be implemented in manufacturing systems’ fundamental design as they constitute much of the operational flexibility available. To this end, smart and more flexible solutions for production planning and control (PPC) are developed. However, scheduling or sequencing is often only considered isolated in a predefined stable environment. Moreover, their orientation on the fundamental logic of the existing IT solutions and their applicability in a dynamic environment is limited. This paper presents a conceptual model for a task-based description logic that can be applied to factory planning, technology planning, and operational control. By using service-oriented architectures, the goal is to generate smart manufacturing systems. The logic is designed to allow for easy and automated maintenance. It is compatible with the existing resource and process allocation logic across operational and strategic factory and production planning.
Melting probes are a proven tool for the exploration of thick ice layers and clean sampling of subglacial water on Earth. Their compact size and ease of operation also make them a key technology for the future exploration of icy moons in our Solar System, most prominently Europa and Enceladus. For both mission planning and hardware engineering, metrics such as efficiency and expected performance in terms of achievable speed, power requirements, and necessary heating power have to be known.
Theoretical studies aim at describing thermal losses on the one hand, while laboratory experiments and field tests allow an empirical investigation of the true performance on the other hand. To investigate the practical value of a performance model for the operational performance in extraterrestrial environments, we first contrast measured data from terrestrial field tests on temperate and polythermal glaciers with results from basic heat loss models and a melt trajectory model. For this purpose, we propose conventions for the determination of two different efficiencies that can be applied to both measured data and models. One definition of efficiency is related to the melting head only, while the other definition considers the melting probe as a whole. We also present methods to combine several sources of heat loss for probes with a circular cross-section, and to translate the geometry of probes with a non-circular cross-section to analyse them in the same way. The models were selected in a way that minimizes the need to make assumptions about unknown parameters of the probe or the ice environment.
The results indicate that currently used models do not yet reliably reproduce the performance of a probe under realistic conditions. Melting velocities and efficiencies are constantly overestimated by 15 to 50 % in the models, but qualitatively agree with the field test data. Hence, losses are observed, that are not yet covered and quantified by the available loss models. We find that the deviation increases with decreasing ice temperature. We suspect that this mismatch is mainly due to the too restrictive idealization of the probe model and the fact that the probe was not operated in an efficiency-optimized manner during the field tests. With respect to space mission engineering, we find that performance and efficiency models must be used with caution in unknown ice environments, as various ice parameters have a significant effect on the melting process. Some of these are difficult to estimate from afar.
Achieving the 17 Sustainable Development Goals (SDGs) set by the United Nations (UN) in 2015 requires global collaboration between different stakeholders. Industry, and in particular engineers who shape industrial developments, have a special role to play as they are confronted with the responsibility to holistically reflect sustainability in industrial processes. This means that, in addition to the technical specifications, engineers must also question the effects of their own actions on an ecological, economic and social level in order to ensure sustainable action and contribute to the achievement of the SDGs. However, this requires competencies that enable engineers to apply all three pillars of sustainability to their own field of activity and to understand the global impact of industrial processes. In this context, it is relevant to understand how industry already reflects sustainability and to identify competences needed for sustainable development.
In addition to the technical content, modern courses at university should also teach professional skills to enhance the competencies of students towards their future work. The competency driven approach including technical as well as professional skills makes it necessary to find a suitable way for the integration into the corresponding module in a scalable and flexible manner. Agile development, for example, is essential for the development of modern systems and applications and makes use of dedicated professional skills of the team members, like structured group dynamics and communication, to enable the fast and reliable development. This paper presents an easy to integrate and flexible approach to integrate Scrum, an agile development method, into the lab of an existing module. Due to the different role models of Scrum the students have an individual learning success, gain valuable insight into modern system development and strengthen their communication and organization skills. The approach is implemented and evaluated in the module Vehicle Systems, but it can be transferred easily to other technical courses as well. The evaluation of the implementation considers feedback of all stakeholders, students, supervisor and lecturers, and monitors the observations during project lifetime.
Throughout the last decade, and particularly in 2022, water scarcity has become a critical concern in Morocco and other Mediterranean countries. The lack of rainfall during spring was worsened by a succession of heat waves during the summer. To address this drought, innovative solutions, including the use of new technologies such as hydrogels, will be essential to transform agriculture. This paper presents the findings of a study that evaluated the impact of hydrogel application on onion (Allium cepa) cultivation in Meknes, Morocco. The treatments investigated in this study comprised two different types of hydrogel-based soil additives (Arbovit® polyacrylate and Huminsorb® polyacrylate), applied at two rates (30 and 20 kg/ha), and irrigated at two levels of water supply (100% and 50% of daily crop evapotranspiration; ETc). Two control treatments were included, without hydrogel application and with both water amounts. The experiment was conducted in an open field using a completely randomized design. The results indicated a significant impact of both hydrogel-type dose and water dose on onion plant growth, as evidenced by various vegetation parameters. Among the hydrogels tested, Huminsorb® Polyacrylate produced the most favorable outcomes, with treatment T9 (100%, HP, 30 kg/ha) yielding 70.55 t/ha; this represented an increase of 11 t/ha as compared to the 100% ETc treatment without hydrogel application. Moreover, the combination of hydrogel application with 50% ETc water stress showed promising results, with treatment T4 (HP, 30 kg, 50%) producing almost the same yield as the 100% ETc treatment without hydrogel while saving 208 mm of water.
Antibias training is increasingly demanded and practiced in academia and industry to increase employees’ sensitivity to discrimination, racism, and diversity. Under the heading of “Diversity Management,” antibias trainings are mainly offered as one-off workshops intending to raise awareness of unconscious biases, create a diversity-affirming corporate culture, promote awareness of the potential of
diversity, and ultimately enable the reflection of diversity in development processes. However, coming from childhood education, research and scientific articles on the sustainable effectiveness of antibias in adulthood, especially in academia, are very scarce. In order to fill this research gap, the article aims to explore how sustainable the effects of individual antibias trainings on participants’ behavior are. In order to investigate this, participant observation in a qualitative pre–post setting was conducted, analyzing antibias training in an academic context. Two observers actively participated in the training sessions and documented the activities and reflection processes of the participants. Overall, the results question the effectiveness of single antibias trainings and show that a target-group adaptive approach is mandatory owing to the background of the approach in early childhood education. Therefore, antibias work needs to be adapted to the target group’s needs and realities of life. Furthermore, the study reveals that single antibias trainings must be embedded in a holistic diversity management approach to stimulate sustainable reflection processes among the target group. This article is one of the first to scientifically evaluate antibias training effectiveness, especially in engineering sciences and the university context.
Vita ist ein Produkt zur Unterstützung von Physiotherapie und Rehabilitation für moderne digitale Profis. Es hilft beim Aufspüren und Erkennen von Haltungsfehlern und gibt positives und sinnvolles Feedback. Ziel des Feedbacks ist es, ein Gefühl des Vertrauens in den Genesungsprozess zu schaffen und durch die Nachahmung der menschlichen Berührung neue, positive Haltungsgewohnheiten zu entwickeln und zu kultivieren.
Unsaid ist ein didaktisches Starterkit für offene Gespräche über Alltagssexismus mit einem Schwerpunkt auf sexueller Belästigung im öffentlichen Raum. Es beinhaltet mehrere Schritte – die Broschüre bietet euch das benötigte Wissen für einen konstruktiven Diskurs. Zusätzlich sind Karten mit Fragen enthalten, die dazu anregen, sexistische Denkmuster und Verhaltensweisen im Alltag zu erkennen und zu reflektieren. Und schließlich zeigt es konkrete Aktionen auf, wie ihr selbst aktiv werden und euch gegen sexistisches Verhalten aussprechen könnt. Das Kit ist darauf ausgerichtet, dass Lehrende an weiterführenden Schulen es in ihren Unterricht integrieren können. Ihr könnt es jedoch genauso gut unter euren Freund*innen, Kolleg*innen oder anderen Interessierten nutzen, um eure Meinungen und Erfahrungen miteinander zu teilen. Unsaid ist ein weiterer Schritt, um Alltagssexismus zu bekämpfen und eine Gesellschaft zu schaffen, in der Gleichberechtigung und Respekt selbstverständlich sind.
Werkstatt voller Historie
(2023)
Das Buch „Werkstatt voller Historie“ gibt einen Einblick in das Handwerk der Restaurierung und Konservierung. Wir leben in einer Gesellschaft, die von Konsum und schneller Verfügbarkeit geprägt ist. Produkte werden in Massen produziert, genutzt und oft schon nach kurzer Zeit wieder weggeworfen. Durch diese Mentalität der Wegwerfgesellschaft werden die Ressourcen unserer Erde erschöpft, und Umweltprobleme werden immer größer. Deshalb ist es wichtig, sich intensiv mit der Bewahrung von Kulturgut auseinanderzusetzen. Durch die Verwendung von Illustrationen und visuellen Darstellungen erleichtert das Buch die Kommunikation. Dadurch kann der Restaurierungsprozess einfacher verstanden werden. Mit dem Projekt soll das Interesse geweckt und über die Grundlagen und Herausforderungen der Restaurierung aufgeklärt werden.
Bachelorzeit
(2023)
Die Bachelorarbeit behandelt die Konzeption und Produktion der Sendung "Bachelorzeit". Ziel ist es, eine innovative Plattform für junge Zuschauer:innen zu schaffen und Einblicke in das Leben und die Themen der Stadt Aachen zu geben. Die Arbeit umfasst den gesamten Produktionsprozess inklusive der Einbindung der Zuschauer:innen und der visuellen Gestaltung. Die erfolgreiche Umsetzung ermöglicht eine ansprechende und nahbare Atmosphäre für ein jüngeres Publikum.
In times of social climate protection movements, such as Fridays for Future, the priorities of society, industry and higher education are currently changing. The consideration of sustainability challenges is increasing. In the context of sustainable development, social skills are crucial to achieving the United Nations Sustainable Development Goals (SDGs). In particular, the impact that educational activities have on people, communities and society is therefore coming to the fore. Research has shown that people with high levels of social competence are better able to manage stressful situations, maintain positive relationships and communicate effectively. They are also associated with better academic performance and career success. However, especially in engineering programs, the social pillar is underrepresented compared to the environmental and economic pillars.
In response to these changes, higher education institutions should be more aware of their social impact - from individual forms of teaching to entire modules and degree programs. To specifically determine the potential for improvement and derive resulting change for further development, we present an initial framework for social impact measurement by transferring already established approaches from the business sector to the education sector. To demonstrate the applicability, we measure the key competencies taught in undergraduate engineering programs in Germany.
The aim is to prepare the students for success in the modern world of work and their future contribution to sustainable development. Additionally, the university can include the results in its sustainability report. Our method can be applied to different teaching methods and enables their comparison.
This book is based on a multimedia course for biological and chemical engineers, which is designed to trigger students' curiosity and initiative. A solid basic knowledge of thermodynamics and kinetics is necessary for understanding many technical, chemical, and biological processes.
The one-semester basic lecture course was divided into 12 workshops (chapters). Each chapter covers a practically relevant area of physical chemistry and contains the following didactic elements that make this book particularly exciting and understandable:
- Links to Videos at the start of each chapter as preparation for the workshop
- Key terms (in bold) for further research of your own
- Comprehension questions and calculation exercises with solutions as learning checks
- Key illustrations as simple, easy-to-replicate blackboard pictures
Humorous cartoons for each workshop (by Faelis) additionally lighten up the text and facilitate the learning process as a mnemonic. To round out the book, the appendix includes a summary of the most popular experiments in basic physical chemistry courses, as well as suggestions for designing workshops with exhibits, experiments, and "questions of the day."
Suitable for students minoring in chemistry; chemistry majors are sure to find this slimmed-down, didactically valuable book helpful as well. The book is excellent for self-study.
Damit Sie auch in den immer häufiger werdenden Onlineveranstaltungen als Moderator gut bestehen, sollten Sie wissen, was bei der Onlinemoderation im Besonderen zu beachten ist.
In diesem dritten Teil der Beitragsserie erfahren Sie, warum online anders als offline ist. Die technischen Möglichkeiten werden vorgestellt und auch wie diese zu nutzen sind. Schließlich erhalten Sie Tipps, die Sie beim Sprechen online beachten sollten.
Damit Sie auch in den immer häufiger werdenden Onlineveranstaltungen als Moderator gut bestehen, sollten Sie wissen, was bei der Onlinemoderation im Besonderen zu beachten ist.
In diesem dritten Teil der Beitragsserie erfahren Sie, warum online anders als offline ist. Die technischen Möglichkeiten werden vorgestellt und auch wie diese zu nutzen sind. Schließlich erhalten Sie Tipps, die Sie beim Sprechen online beachten sollten.
06| Warum es gemeinsam besser geht
10| Interview
14| Wer ist hier der Boss?
18| Schnittstelle zwischen Mensch und Technik
22| Zweite Heimat Jülich
28| Zwischen Angst und Hoffnung
32| Eine Sternstunde für die FH Aachen
36| Gegen alle Widerstände
38| Ein Ort, der bleibt
42| Der Aufblühende
46| Der Computer sitzt am Steuer
52| Da geht das Herz auf
54| Hoch hinaus
58| Beratungsangebote
60| Das alte Schätzchen
Existing residential buildings have an average lifetime of 100 years. Many of these buildings will exist for at least another 50 years. To increase the efficiency of these buildings while keeping costs at reasonable rates, they can be retrofitted with sensors that deliver information to central control units for heating, ventilation and electricity. This retrofitting process should happen with minimal intervention into existing infrastructure and requires new approaches for sensor design and data transmission. At FH Aachen University of Applied Sciences, students of different disciplines work together to learn how to design, build, deploy and operate such sensors. The presented teaching project already created a low power design for a combined CO2, temperature and humidity measurement device that can be easily integrated into most home automation systems
This paper presents an approach for reducing the cognitive load for humans working in quality control (QC) for production processes that adhere to the 6σ -methodology. While 100% QC requires every part to be inspected, this task can be reduced when a human-in-the-loop QC process gets supported by an anomaly detection system that only presents those parts for manual inspection that have a significant likelihood of being defective. This approach shows good results when applied to image-based QC for metal textile products.
Assistance systems have been widely adopted in the manufacturing sector to facilitate various processes and tasks in production environments. However, existing systems are mostly equipped with rigid functional logic and do not provide individual user experiences or adapt to their capabilities. This work integrates human factors in assistance systems by adjusting the hardware and instruction presented to the workers’ cognitive and physical demands. A modular system architecture is designed accordingly, which allows a flexible component exchange according to the user and the work task. Gamification, the use of game elements in non-gaming contexts, has been further adopted in this work to provide level-based instructions and personalised feedback. The developed framework is validated by applying it to a manual workstation for industrial assembly routines.
Next-generation aircraft designs often incorporate multiple large propellers attached along the wingspan. These highly flexible dynamic systems can exhibit uncommon aeroelastic instabilities, which should be carefully investigated to ensure safe operation. The interaction between the propeller and the wing is of particular importance. It is known that whirl flutter is stabilized by wing motion and wing aerodynamics. This paper investigates the effect of a propeller onto wing flutter as a function of span position and mounting stiffness between the propeller and wing. The analysis of a comparison between a tractor and pusher configuration has shown that the coupled system is more stable than the standalone wing for propeller positions near the wing tip for both configurations. The wing fluttermechanism is mostly affected by the mass of the propeller and the resulting change in eigenfrequencies of the wing. For very weak mounting stiffnesses, whirl flutter occurs, which was shown to be stabilized compared to a standalone propeller due to wing motion. On the other hand, the pusher configuration is, as to be expected, the more critical configuration due to the attached mass behind the elastic axis.
This work proposes a hybrid algorithm combining an Artificial Neural Network (ANN) with a conventional local path planner to navigate UAVs efficiently in various unknown urban environments. The proposed method of a Hybrid Artificial Neural Network Avoidance System is called HANNAS. The ANN analyses a video stream and classifies the current environment. This information about the current Environment is used to set several control parameters of a conventional local path planner, the 3DVFH*. The local path planner then plans the path toward a specific goal point based on distance data from a depth camera. We trained and tested a state-of-the-art image segmentation algorithm, PP-LiteSeg. The proposed HANNAS method reaches a failure probability of 17%, which is less than half the failure probability of the baseline and around half the failure probability of an improved, bio-inspired version of the 3DVFH*. The proposed HANNAS method does not show any disadvantages regarding flight time or flight distance.
This work presents the Multi-Bees-Tracker (MBT3D) algorithm, a Python framework implementing a deep association tracker for Tracking-By-Detection, to address the challenging task of tracking flight paths of bumblebees in a social group. While tracking algorithms for bumblebees exist, they often come with intensive restrictions, such as the need for sufficient lighting, high contrast between the animal and background, absence of occlusion, significant user input, etc. Tracking flight paths of bumblebees in a social group is challenging. They suddenly adjust movements and change their appearance during different wing beat states while exhibiting significant similarities in their individual appearance. The MBT3D tracker, developed in this research, is an adaptation of an existing ant tracking algorithm for bumblebee tracking. It incorporates an offline trained appearance descriptor along with a Kalman Filter for appearance and motion matching. Different detector architectures for upstream detections (You Only Look Once (YOLOv5), Faster Region Proposal Convolutional Neural Network (Faster R-CNN), and RetinaNet) are investigated in a comparative study to optimize performance. The detection models were trained on a dataset containing 11359 labeled bumblebee images. YOLOv5 reaches an Average Precision of AP = 53, 8%, Faster R-CNN achieves AP = 45, 3% and RetinaNet AP = 38, 4% on the bumblebee validation dataset, which consists of 1323 labeled bumblebee images. The tracker’s appearance model is trained on 144 samples. The tracker (with Faster R-CNN detections) reaches a Multiple Object Tracking Accuracy MOTA = 93, 5% and a Multiple Object Tracking Precision MOTP = 75, 6% on a validation dataset containing 2000 images, competing with state-of-the-art computer vision methods. The framework allows reliable tracking of different bumblebees in the same video stream with rarely occurring identity switches (IDS). MBT3D has much lower IDS than other commonly used algorithms, with one of the lowest false positive rates, competing with state-of-the-art animal tracking algorithms. The developed framework reconstructs the 3-dimensional (3D) flight paths of the bumblebees by triangulation. It also handles and compares two alternative stereo camera pairs if desired.
Muscle function is compromised by gravitational unloading in space affecting overall musculoskeletal health. Astronauts perform daily exercise programmes to mitigate these effects but knowing which muscles to target would optimise effectiveness. Accurate inflight assessment to inform exercise programmes is critical due to lack of technologies suitable for spaceflight. Changes in mechanical properties indicate muscle health status and can be measured rapidly and non-invasively using novel technology. A hand-held MyotonPRO device enabled monitoring of muscle health for the first time in spaceflight (> 180 days). Greater/maintained stiffness indicated countermeasures were effective. Tissue stiffness was preserved in the majority of muscles (neck, shoulder, back, thigh) but Tibialis Anterior (foot lever muscle) stiffness decreased inflight vs. preflight (p < 0.0001; mean difference 149 N/m) in all 12 crewmembers. The calf muscles showed opposing effects, Gastrocnemius increasing in stiffness Soleus decreasing. Selective stiffness decrements indicate lack of preservation despite daily inflight countermeasures. This calls for more targeted exercises for lower leg muscles with vital roles as ankle joint stabilizers and in gait. Muscle stiffness is a digital biomarker for risk monitoring during future planetary explorations (Moon, Mars), for healthcare management in challenging environments or clinical disorders in people on Earth, to enable effective tailored exercise programmes.
In this paper, the use of reinforcement learning (RL) in control systems is investigated using a rotatory inverted pendulum as an example. The control behavior of an RL controller is compared to that of traditional LQR and MPC controllers. This is done by evaluating their behavior under optimal conditions, their disturbance behavior, their robustness and their development process. All the investigated controllers are developed using MATLAB and the Simulink simulation environment and later deployed to a real pendulum model powered by a Raspberry Pi. The RL algorithm used is Proximal Policy Optimization (PPO). The LQR controller exhibits an easy development process, an average to good control behavior and average to good robustness. A linear MPC controller could show excellent results under optimal operating conditions. However, when subjected to disturbances or deviations from the equilibrium point, it showed poor performance and sometimes instable behavior. Employing a nonlinear MPC Controller in real time was not possible due to the high computational effort involved. The RL controller exhibits by far the most versatile and robust control behavior. When operated in the simulation environment, it achieved a high control accuracy. When employed in the real system, however, it only shows average accuracy and a significantly greater performance loss compared to the simulation than the traditional controllers. With MATLAB, it is not yet possible to directly post-train the RL controller on the Raspberry Pi, which is an obstacle to the practical application of RL in a prototyping or teaching setting. Nevertheless, RL in general proves to be a flexible and powerful control method, which is well suited for complex or nonlinear systems where traditional controllers struggle.
Im Hinblick auf die Klimaziele der Bundesrepublik Deutschland konzentriert sich das Projekt Diggi Twin auf die nachhaltige Gebäudeoptimierung. Grundlage für eine ganzheitliche Gebäudeüberwachung und -optimierung bildet dabei die Digitalisierung und Automation im Sinne eines Smart Buildings. Das interdisziplinäre Projekt der FH Aachen hat das Ziel, ein bestehendes Hochschulgebäude und einen Neubau an klimaneutrale Standards anzupassen. Im Rahmen des Projekts werden bekannte Verfahren, wie das Building Information Modeling (BIM), so erweitert, dass ein digitaler Gebäudezwilling entsteht. Dieser kann zur Optimierung des Gebäudebetriebs herangezogen werden, sowie als Basis für eine Erweiterung des Bewertungssystems Nachhaltiges Bauen (BNB) dienen. Mithilfe von Sensortechnologie und künstlicher Intelligenz kann so ein präzises Monitoring wichtiger Gebäudedaten erfolgen, um ungenutzte Energieeinsparpotenziale zu erkennen und zu nutzen. Das Projekt erforscht und setzt methodische Erkenntnisse zu BIM und digitalen Gebäudezwillingen praxisnah um, indem es spezifische Fragen zur Energie- und Ressourceneffizienz von Gebäuden untersucht und konkrete Lösungen für die Gebäudeoptimierung entwickelt.
Das Projekt "ARRK Journeys" entwickelt ein neues Dokumentarfilm-Format, das darauf abzielt, potenzielle Mitarbeiter für die ARRK Engineering GmbH zu gewinnen
Das Ziel des Projekts ist es, die Vielfalt an Karrieremöglichkeiten bei der ARRK Engineering GmbH aufzuzeigen und die Attraktivität des Unternehmens als Arbeitgeber zu betonen. Durch individuelle Mitarbeitergeschichten werden die Fragen beantwortet, warum eine berufliche Laufbahn bei ARRK erstrebenswert ist, ob jeder die Möglichkeit hat, bei ARRK zu arbeiten, und welche Entwicklungsmöglichkeiten das Unternehmen bietet. "ARRK Journeys" betont das Wohlbefinden der Mitarbeiter und ihre persönliche Bindung zum Unternehmen, um eine positive Arbeitgebermarke zu schaffen.
"ARRK Journeys" präsentiert die ARRK Engineering GmbH als attraktiven Arbeitgeber und inspiriert potenzielle Mitarbeiter dazu, ihren eigenen Weg zu finden.
Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10% vs. 20%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.
To gain insight on chemical sterilization processes, the influence of temperature (up to 70 °C), intense green light, and hydrogen peroxide (H₂O₂) concentration (up to 30% in aqueous solution) on microbial spore inactivation is evaluated by in-situ Raman spectroscopy with an optical trap. Bacillus atrophaeus is utilized as a model organism. Individual spores are isolated and their chemical makeup is monitored under dynamically changing conditions (temperature, light, and H₂O₂ concentration) to mimic industrially relevant process parameters for sterilization in the field of aseptic food processing. While isolated spores in water are highly stable, even at elevated temperatures of 70 °C, exposure to H₂O₂ leads to a loss of spore integrity characterized by the release of the key spore biomarker dipicolinic acid (DPA) in a concentration-dependent manner, which indicates damage to the inner membrane of the spore. Intensive light or heat, both of which accelerate the decomposition of H₂O₂ into reactive oxygen species (ROS), drastically shorten the spore lifetime, suggesting the formation of ROS as a rate-limiting step during sterilization. It is concluded that Raman spectroscopy can deliver mechanistic insight into the mode of action of H₂O₂-based sterilization and reveal the individual contributions of different sterilization methods acting in tandem.
Many important properties of bacterial cellulose (BC), such as moisture absorption capacity, elasticity and tensile strength, largely depend on its structure. This paper presents a study on the effect of the drying method on BC films produced by Medusomyces gisevii using two different procedures: room temperature drying (RT, (24 ± 2 °C, humidity 65 ± 1%, dried until a constant weight was reached) and freeze-drying (FD, treated at − 75 °C for 48 h). BC was synthesized using one of two different carbon sources—either glucose or sucrose. Structural differences in the obtained BC films were evaluated using atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction. Macroscopically, the RT samples appeared semi-transparent and smooth, whereas the FD group exhibited an opaque white color and sponge-like structure. SEM examination showed denser packing of fibrils in FD samples while RT-samples displayed smaller average fiber diameter, lower surface roughness and less porosity. AFM confirmed the SEM observations and showed that the FD material exhibited a more branched structure and a higher surface roughness. The samples cultivated in a glucose-containing nutrient medium, generally displayed a straight and ordered shape of fibrils compared to the sucrose-derived BC, characterized by a rougher and wavier structure. The BC films dried under different conditions showed distinctly different crystallinity degrees, whereas the carbon source in the culture medium was found to have a relatively small effect on the BC crystallinity.
Frequency mixing magnetic detection (FMMD) is a sensitive and selective technique to detect magnetic nanoparticles (MNPs) serving as probes for binding biological targets. Its principle relies on the nonlinear magnetic relaxation dynamics of a particle ensemble interacting with a dual frequency external magnetic field. In order to increase its sensitivity, lower its limit of detection and overall improve its applicability in biosensing, matching combinations of external field parameters and internal particle properties are being sought to advance FMMD. In this study, we systematically probe the aforementioned interaction with coupled Néel–Brownian dynamic relaxation simulations to examine how key MNP properties as well as applied field parameters affect the frequency mixing signal generation. It is found that the core size of MNPs dominates their nonlinear magnetic response, with the strongest contributions from the largest particles. The drive field amplitude dominates the shape of the field-dependent response, whereas effective anisotropy and hydrodynamic size of the particles only weakly influence the signal generation in FMMD. For tailoring the MNP properties and parameters of the setup towards optimal FMMD signal generation, our findings suggest choosing large particles of core sizes dc > 25 nm nm with narrow size distributions (σ < 0.1) to minimize the required drive field amplitude. This allows potential improvements of FMMD as a stand-alone application, as well as advances in magnetic particle imaging, hyperthermia and magnetic immunoassays.
The deformation and damage laws of non-homogeneous irregular structural planes in rocks are the basis for studying the stability of rock engineering. To investigate the damage characteristics of rock containing non-parallel fissures, uniaxial compression tests and numerical simulations were conducted on sandstone specimens containing three non-parallel fissures inclined at 0°, 45° and 90° in this study. The characteristics of crack initiation and crack evolution of fissures with different inclinations were analyzed. A constitutive model for the discontinuous fractures of fissured sandstone was proposed. The results show that the fracture behaviors of fissured sandstone specimens are discontinuous. The stress–strain curves are non-smooth and can be divided into nonlinear crack closure stage, linear elastic stage, plastic stage and brittle failure stage, of which the plastic stage contains discontinuous stress drops. During the uniaxial compression test, the middle or ends of 0° fissures were the first to crack compared to 45° and 90° fissures. The end with small distance between 0° and 45° fissures cracked first, and the end with large distance cracked later. After the final failure, 0° fissures in all specimens were fractured, while 45° and 90° fissures were not necessarily fractured. Numerical simulation results show that the concentration of compressive stress at the tips of 0°, 45° and 90° fissures, as well as the concentration of tensile stress on both sides, decreased with the increase of the inclination angle. A constitutive model for the discontinuous fractures of fissured sandstone specimens was derived by combining the logistic model and damage mechanic theory. This model can well describe the discontinuous drops of stress and agrees well with the whole processes of the stress–strain curves of the fissured sandstone specimens.
Analyzing electroencephalographic (EEG) time series can be challenging, especially with deep neural networks, due to the large variability among human subjects and often small datasets. To address these challenges, various strategies, such as self-supervised learning, have been suggested, but they typically rely on extensive empirical datasets. Inspired by recent advances in computer vision, we propose a pretraining task termed "frequency pretraining" to pretrain a neural network for sleep staging by predicting the frequency content of randomly generated synthetic time series. Our experiments demonstrate that our method surpasses fully supervised learning in scenarios with limited data and few subjects, and matches its performance in regimes with many subjects. Furthermore, our results underline the relevance of frequency information for sleep stage scoring, while also demonstrating that deep neural networks utilize information beyond frequencies to enhance sleep staging performance, which is consistent with previous research. We anticipate that our approach will be advantageous across a broad spectrum of applications where EEG data is limited or derived from a small number of subjects, including the domain of brain-computer interfaces.
Bauwirtschaft
(2024)
Die Leistungen der Bauwirtschaft und deren wirtschaftliche Bedeutung in Deutschland werden anhand einer Vielzahl statistischer Daten verdeutlicht. Die im Vergleich zu anderen Wirtschaftsbereichen auftretenden branchenspezifischen Besonderheiten der Bauwirtschaft werden anhand von verschiedenen Kriterien herausgearbeitet. Das Zusammenspiel der einzelnen Akteure des Sektors und die dabei sich ergebenden bzw. zu beachtenden Rechts- und Vertragsgrundlagen werden dargestellt. Aufgrund der meist erheblichen Höhe des eingesetzten Kapitals werden auch notwendige Formen der Risikoabsicherungen und der in der Branche üblichen und teilweise vorgeschriebenen Versicherungsmöglichkeiten angesprochen.
Durch das öffentliche Baurecht werden die Zulässigkeit, die Grenzen, die Ordnung und die Förderung der baulichen Nutzung des Bodens geregelt.
Die Ausschreibung und die Vergabe sind von essenzieller Bedeutung für ein Bauvorhaben und werden deshalb in der HOAI mit zwei Leistungsphasen abgebildet: nämlich mit der Leistungsphase 6 Vorbereitung der Vergabe sowie der Leistungsphase 7 Mitwirkung bei der Vergabe. Im Zuge der Ausschreibung und der Vergabe werden die für den AG anfallenden Kosten festgelegt und bilden somit die letzte größere Stellschraube für Preiseinsparungen.
n diesem Kapitel werden die Abrechnungsvorschriften wichtiger ATV kurz, aber umfassend zusammengestellt. Einigen Abrechnungsbestimmungen für Einzelleistungen, die keine Nebenleistungen sind ((siehe DIN 18299 und Abschnitt 4 der jeweiligen ATV), sind mit aufgenommen worden; die ATV enthalten jedoch weitergehende Festlegungen über Nebenleistungen und Besondere Leistungen.
Im Anschluss folgen Hinweise zu den Toleranzen im Hochbau sowie im Straßenbau.
Boden, Baugrube, Verbau
(2024)
Die Lösung den Baugrund betreffender Fragestellungen beginnen i. d. R. mit der Durchführung von Baugrunderkundungen, um alle notwendigen Parameter zu erhalten, die für die Planung und Durchführung von Bauvorhaben notwendig sind. Im Folgenden werden die wichtigsten Erkundungen in Abhängigkeit der erforderlichen Güteklasse der Proben beschrieben und vorgestellt.
Die Arbeitsvorbereitung, als ein wesentliches Aufgabengebiet des Baubetriebswesens, ist von enormer Bedeutung für den Erfolg eines Bauprojektes. Die Arbeitsvorbereitung lässt sich zeitlich sowohl in der Angebotsphase (kalkulationsbegleitende Arbeitsvorbereitung), in der Vorbereitungsphase der Baustelle (von Auftragsvergabe bis Baubeginn) als auch baubegleitend einordnen.
Baustoffe
(2024)
Die fotografische Arbeit "Almanya" veranschaulicht Teilaspekte der türkischen Kultur anhand von Repräsentantinnen und Repräsentanten der türkeistämmigen Community in Deutschland. Mit einem Fokus auf Kulinarik und Formen des Zusammenlebens werden Menschen mit türkischen Wurzeln porträtiert, sodass am Ende ein Einblick in deren Lebens- und Gedankenwelt ermöglicht wird und kulinarische Brücken zwischen Deutschen und der türkischen Kultur gebaut werden. Die enthaltene Botschaft, welche das Projekt den Rezipient:innen überbringt, ist in einem multikulturellen Land wie Deutschland von großer Wichtigkeit für gegenseitiges Verständnis und bildet den Boden für ein harmonisches Miteinander.
Durch die Einführung von Building Information Modeling (BIM) sowohl projektspezifisch als auch in ganze Unternehmungen hat die Baubranche einen weitreichenden Veränderungsprozess angestoßen.
Building Information Modeling kann als eine Methode angesehen werden, um die Informationsasymmetrien zwischen den Projektbeteiligten so gering wie möglich zu halten.