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Bioakustik, ein interdisziplinäres Gebiet der Biologie zwischen Klang und Umwelt, erfährt durch die Kunstkopf-Hörbilder des Naturforschers und Tonmeisters Walter Tilgner eine plastische, wissenschaftliche Erweiterung. Mit dem binauralen Kunstkopfverfahren zeichnet er nicht nur einzelne tier- und vogelkundliche Laute auf, sondern die gesamte Umgebung und ihr typisches Klangbild. Während die Tierstimmenanalyse etwa der Ornithologie einzelne Formen des Vogelgesangs untersucht, geht es ihm und Hörkünstlern wie Gordon Hempton, dem ‚Soundtracker‘, um das Wechselspiel zwischen den Arten in Zeit und Raum. Auch die pädagogische Seite spielt eine Rolle, um den Rezipienten Naturklang als wertvolle Ressource nahezubringen. 1985 hat der Pionier Tilgner die ersten Naturlandschaften vollständig digital aufgenommen und bei WERGO mit dem Label ‚Natural Sound‘ als CD publiziert. Für den Komponisten und Wissenschaftler Dr. Bernie Krause aus Kalifornien repräsentieren solche Aufnahmen ökologische Nischen in der Landschaft, von typischen Klangverläufen geprägt. In seinem eigenen Vergleich dichter Naturräume in Südamerika, Afrika und Asien werden sie unverwechselbar als akustischer Fingerabdruck nachweisbar. Der Künstler- Forscher hat mit der Spektralanalyse so nicht nur seine ‚Nischen-Hypothese‘ entwickelt und empirisch bestätigt, sondern auch den Begriff der Biophonie geprägt: Naturklänge entfalten sich wie in einem musikalischen Stück, sie sind der Komposition einer (Bio-)Symphonie vergleichbar. Die Stimmen der Spezies bilden arin den ‚materialen Klang‘ (den Ausdruck verdanken wir dem Komponisten Johannes Wallmann in Berlin). Darauf wirken die zeitlichen Prozesse und räumlichen Faktoren der Umwelt, als ‚Geophony‘ aus Klima und Flora, durch Sonne, Wind, Erde und Wasser. Schließlich verändert auch der Mensch die Naturlandschaft durch technische Geräte, wie in der Tonaufnahme, und durch extensives Wirtschaften hin zur ‚Anthrophony‘. Der Klang der Natur ist also menschgemacht, und die Aufnahmen bedeuten nicht nur wertvollen Rohstoff für die Medien. Bioakustik und Biophonie fordern den Dialog von und über Natur und Kultur immer wieder neu heraus, wie hier im Spektrogramm einer Waldcollage, mit einer starken Motorsäge als Mittelpunkt [2].
1000 Meilen unter Strom, Rekordfahrt des in Offenburg entwickelten eFahrzeugs "Schluckspecht"
(2012)
Nach der Entwicklung eines sparsamen Demonstrationsfahrzeugs mit Dieselmotor und Brennstoffzellenfahrzeuge wurde ein Batteriefahrzeug entwickelt, das in Südafrika unter der Aufsicht von FIA-Ingenieuren 626,6 km fuhr, ohne dass die Batterie aufgeladen werden musste. Ein Demonstrationsfahrzeug des Japan Electrical Vehicle Club hielt den damaligen Weltrekordmit 555,6 km.
Knight Götz von Berlichingen (1480–1562) lost his right hand distal to the wrist due to a cannon ball splinter injury in 1504 in the Landshut War of Succession at the age of 24. Early on, Götz commissioned a gunsmith to build the first “Iron Hand,” in which the artificial thumb and two finger blocks could be moved in their basic joints by a spring mechanism and released by a push button. Some years later, probably around 1530, a second “Iron Hand” was built, in which the fingers could be moved passively in all joints. In this review, the 3D computer-aided design (CAD) reconstructions and 3D multi-material polymer replica printings of the first “Iron hand“, which were developed in the last few years at Offenburg University, are presented. Even by today’s standards, the first “Iron Hand”—as could be shown in the replicas—demonstrates sophisticated mechanics and well thought-out functionality and still offers inspiration and food for discussion when it comes to the question of an artificial prosthetic replacement for a hand. It is also outlined how some of the ideas of this mechanical passive prosthesis can be translated into a modern motorized active prosthetic hand by using simple, commercially available electronic components.
Positioning mobile systems with high accuracy is a prerequisite for intelligent autonomous behavior, both in industrial environments and in field robotics. This paper describes the setup of a robotic platform and its use for the evaluation of simultaneous localization and mapping (SLAM) algorithms. A configuration using a mobile robot Husky A200, and a LiDAR (light detection and ranging) sensor was used to implement the setup. For verification of the proposed setup, different scan matching methods for odometry determination in indoor and outdoor environments are tested. An assessment of the accuracy of the baseline 3D-SLAM system and the selected evaluation system is presented by comparing different scenarios and test situations. It was shown that the hdl_graph_slam in combination with the LiDAR OS1 and the scan matching algorithms FAST_GICP and FAST_VGICP achieves good mapping results with accuracies up to 2 cm.
Recent developments in information and communication technology, along with advanced displaying techniques and high computational performance open up new visualisation methods to both scientists and lecturers. Thus simulations of complex processes [1] can be computed and visualised in image sequences. The particular idea in our approach is the outsourcing of computationally intensive calculations to servers which then send the results back to mobile users. In order to improve interpretations of the visualised results, users can view them in a 3D-perspective or stereoscopically, given the technical requirements. Today’s technology even permits to view these visualisations on a mobile phone. An example for such a computationally intensive calculation originating from the theory of relativity is depicted in Figure 4.1-1.
Disturbances of the cardiac conduction system causing reentry mechanisms above the atrioventricular (AV) node are induced by at least one accessory pathway with different conducting properties and refractory periods. This work aims to further develop the already existing and continuously expanding Offenburg heart rhythm model to visualise the most common supraventricular reentry tachycardias to provide a better understanding of the cause of the respective reentry mechanism.
Background: This paper presents a novel approach for a hand prosthesis consisting of a flexible, anthropomorphic, 3D-printed replacement hand combined with a commercially available motorized orthosis that allows gripping.
Methods: A 3D light scanner was used to produce a personalized replacement hand. The wrist of the replacement hand was printed of rigid material; the rest of the hand was printed of flexible material. A standard arm liner was used to enable the user’s arm stump to be connected to the replacement hand. With computer-aided design, two different concepts were developed for the scanned hand model: In the first concept, the replacement hand was attached to the arm liner with a screw. The second concept involved attaching with a commercially available fastening system; furthermore, a skeleton was designed that was located within the flexible part of the replacement hand.
Results: 3D-multi-material printing of the two different hands was unproblematic and inexpensive. The printed hands had approximately the weight of the real hand. When testing the replacement hands with the orthosis it was possible to prove a convincing everyday functionality. For example, it was possible to grip and lift a 1-L water bottle. In addition, a pen could be held, making writing possible.
Conclusions: This first proof-of-concept study encourages further testing with users.
In 4D printing, an additively manufactured component is given the ability to change its shape or function in an intended and useful manner over time. The technology of 4D printing is still in an early stage of development. Nevertheless, interesting research and initial applications exist in the literature. In this work, a novel methodical approach is presented that helps transfer existing 4D printing research results and knowledge into solving application tasks systematically. Moreover, two different smart materials are analyzed, used, and combined following the presented methodical approach to solving the given task in the form of recovering an object from a poorly accessible space. This is implemented by self-positioning, grabbing, and extracting the target object. The first smart material used to realize these tasks is a shape-memory polymer, while the second is a polymer-based magnetic composite. In addition to the presentation and detailed implementation of the methodical approach, the potentials and behavior of the two smart materials are further examined and narrowed down as a result of the investigation. The results show that the developed methodical approach contributes to moving 4D printing closer toward a viable alternative to existing technologies due to its problem-oriented nature.
A simple measuring method for acquiring the radiation pattern of an ultrawide band Vivaldi antenna is presented. The measuring is performed by combining two identical Vivaldi antennas and some of the intrinsic properties of a stepped-frequency continue wave radar (SFCW radar) in the
range from 1.0 GHz to 6.0 GHz. A stepper-motor provided the azimuthal rotation for one of the antennas from 0 ◦ to 360 ◦. The tests have been performed within the conventional environment (laboratory / office) without using an anechoic chamber or absorbing materials. Special measuring devices have not been used either. This method has been tested with different pairs of Vivaldi antennas and it can be also used for different ones (with little or no change in the system), as long as their operational
bandwidth is within the frequency range of the SFCW radar.
Keywords — SFCW Radar, Antenna Gain Characterization,
Azimuthal Radiation Pattern
Gamification is increasingly successful in the field of education and health. However, beyond call-centers and applications in human resources, its utilization within companies remains limited. In this paper, we examine the acceptance of gamification in a large company (with over 17,000 employees) across three generations, namely X, Y, and Z. Furthermore, we investigate which gamification elements are suited for business contexts, such as the dissemination of company principles and facts, or the organization of work tasks. To this end, we conducted focus group discussions, developed the prototype of a gamified company app, and performed a large-scale evaluation with 367 company employees. The results reveal statistically significant intergenerational disparities in the acceptance of gamification: younger employees, especially those belonging to Generation Z, enjoy gamification more than older employees and are most likely to engage with a gamified app in the workplace. The results further show a nuanced range of preferences regarding gamification elements: avatars are popular among all generations, badges are predominantly appreciated by Generations Z and Y, while leaderboards are solely liked by Generation Z. Drawing upon these insights, we provide recommendations for future gamification projects within business contexts. We hope that the results of our study regarding the preferences of the gamification elements and understanding generational differences in acceptance and usage of gamification will help to create more engaging and effective apps, especially within the corporate landscape.
This paper provides a comprehensive overview of approaches to the determination of isocontours and isosurfaces from given data sets. Different algorithms are reported in the literature for this purpose, which originate from various application areas, such as computer graphics or medical imaging procedures. In all these applications, the challenge is to extract surfaces with a specific isovalue from a given characteristic, so called isosurfaces. These different application areas have given rise to solution approaches that all solve the problem of isocontouring in their own way. Based on the literature, the following four dominant methods can be identified: the marching cubes algorithms, the tessellation-based algorithms, the surface nets algorithms and the ray tracing algorithms. With regard to their application, it can be seen that the methods are mainly used in the fields of medical imaging, computer graphics and the visualization of simulation results. In our work, we provide a broad and compact overview of the common methods that are currently used in terms of isocontouring with respect to certain criteria and their individual limitations. In this context, we discuss the individual methods and identify possible future research directions in the field of isocontouring.
A report from the World Economic Forum (2019) stated loneliness as the third societal stressor in the world, mainly in western countries. Moreover, research shows that loneliness tends to be experienced more severely by young adults than other age groups (Rokach, 2000), which is the case of university students who face profound periods of loneliness when attending university in a new place (Diehl et al., 2018). Digital technology, especially mental health apps (MHapps), have been viewed as promising solutions to address this distress in universities, however, little evidence on this topic reveals uncertainty around how these resources impact individual well-being. Therefore, this research proposed to investigate how the gamified social mobile app Noneliness reduced loneliness rates and other associated mental health issues of students from a German university. As little work has focused on digital apps targeting loneliness, this project also proposed to describe and discuss the app’s design and development processes. A multimethod approach was adopted: literature review on high-efficacy MHapps design, gamification for mental health and loneliness interventions; User Experience Design and Human-centered Computing. Evaluations occurred according to the app’s development iterations, which assessed four versions (from prototype to Beta) through quantitative and qualitative studies with university students. The main results obtained regarding the design aspects were: users' preference for minimalistic interfaces; importance in maintaining privacy and establishing trust among users; students' willingness to use an online support space for emotional and educational support. Most used features were those related to group discussions, private chats and university social events. Preferred gamification elements were those that provided positive reinforcement to motivate social interactions (e.g. Points, Levels and Achievements). Results of a pilot randomized controlled trial with university students (N = 12), showed no statistically significant interactions in reducing loneliness among experimental group members (n = 7, x² = 3.500, p-value = 0.477, Cramer’s V = 0.27) who made continued use of the app for six weeks. On the other hand, the app showed effects of moderate magnitude on loneliness reduction in this group. The app also demonstrated relatively strong magnitude effects on other associated variables, such as depression and stress in the experimental group. In addition to motivating the conduct of further studies with larger samples, the findings point to a potential app effectiveness not only to reduce loneliness, but also other variables that may be associated with the distress.
Lithium-ion batteries exhibit slow voltage dynamics on the minute time scale that are usually associated with transport processes. We present a novel modelling approach toward these dynamics by combining physical and data-driven models into a Grey-box model. We use neural networks, in particular neural ordinary differential equations. The physical structure of the Grey-box model is borrowed from the Fickian diffusion law, where the transport domain is discretized using finite volumes. Within this physical structure, unknown parameters (diffusion coefficient, diffusion length, discretization) and dependencies (state of charge, lithium concentration) are replaced by neural networks and learnable parameters. We perform model-to-model comparisons, using as training data (a) a Fickian diffusion process, (b) a Warburg element, and (c) a resistor-capacitor circuit. Voltage dynamics during constant-current operation and pulse tests as well as electrochemical impedance spectra are simulated. The slow dynamics of all three physical models in the order of ten to 30 min are well captured by the Grey-box model, demonstrating the flexibility of the present approach.
Pure orbital blowout fractures occur within the confines of the internal orbital wall. Restoration of orbital form and volume is paramount to prevent functional and esthetic impairment. The anatomical peculiarity of the orbit has encouraged surgeons to develop implants with customized features to restore its architecture. This has resulted in worldwide clinical demand for patient-specific implants (PSIs) designed to fit precisely in the patient’s unique anatomy. Material extrusion or Fused filament fabrication (FFF) three-dimensional (3D) printing technology has enabled the fabrication of implant-grade polymers such as Polyetheretherketone (PEEK), paving the way for a more sophisticated generation of biomaterials. This study evaluates the FFF 3D printed PEEK orbital mesh customized implants with a metric considering the relevant design, biomechanical, and morphological parameters. The performance of the implants is studied as a function of varying thicknesses and porous design constructs through a finite element (FE) based computational model and a decision matrix based statistical approach. The maximum stress values achieved in our results predict the high durability of the implants, and the maximum deformation values were under one-tenth of a millimeter (mm) domain in all the implant profile configurations. The circular patterned implant (0.9 mm) had the best performance score. The study demonstrates that compounding multi-design computational analysis with 3D printing can be beneficial for the optimal restoration of the orbital floor.
Background:
Ankle braces aim to reduce lateral ankle sprains. Next to protection, factors influencing user compliance, such as sports performance, motion restriction, and users’ perceptions, are relevant for user compliance and thus injury prevention. Novel adaptive protection systems claim to change their mechanical behavior based on the intensity of motion (eg, the inversion velocity), unlike traditional passive concepts of ankle bracing.
Purpose:
To compare the performance of a novel adaptive brace with 2 passive ankle braces while considering protection, sports performance, freedom of motion, and subjective perception.
Study Design:
Controlled laboratory study.
Methods:
The authors analyzed 1 adaptive and 2 passive (one lace-up and one rigid brace) ankle braces, worn in a low-cut, indoor sports shoe, which was also the no-brace reference condition. We performed material testing using an artificial ankle joint system at high and low inversion velocities. Further, 20 male, young, healthy team sports athletes were analyzed using 3-dimensional motion analysis in sports-related movements to address protection, sports performance, and active range of motion dimensions. Participants rated subjective comfort, stability, and restriction experienced when using the products.
Results:
Subjective stability rating was not different between the adaptive and passive systems. The rigid brace was superior in restricting peak inversion during the biomechanical testing compared with the passive braces. However, in the material test, the adaptive brace increased its stiffness by approximately 400% during the fast compared with the slow inversion velocities, demonstrating its adaptive behavior and similar stiffness values to passive braces. We identified minor differences in sports performance tasks. The adaptive brace improved active ankle range of motion and subjective comfort and restriction ratings.
Conclusion:
The adaptive brace offered similar protective effects in high-velocity inversion situations to those of the passive braces while improving range of motion, comfort, and restriction rating during noninjurious motions.
Clinical Relevance:
Protection systems are only effective when used. Compared with traditional passive ankle brace technologies, the novel adaptive brace might increase user compliance by improving comfort and freedom of movement while offering similar protection in injurious situations.
The NaSiO Institute (Institute for Sustainable Silicate Research in Offenburg, https://inasio.hs-offenburg.de/) has been working for years on climate-friendly alternatives to insulation materials and inorganic binders, as well as the reasonable use of construction waste in the building industry. The aim of research is to realize the enormous CO 2 saving potential of the construction sector worldwide. A stopping of climate heating will only succeed if these climate-friendly alternatives are used in the construction industry. This is the only way to realize the enormous CO2 savings that will be needed in future to comply with the Paris Agreement.
Treadmills are essential to the study of human and animal locomotion as well as for applied diagnostics in both sports and medicine. The quantification of relevant biomechanical and physiological variables requires a precise regulation of treadmill belt velocity (TBV). Here, we present a novel method for time-efficient tracking of TBV using standard 3D motion capture technology. Further, we analyzed TBV fluctuations of four different treadmills as seven participants walked and ran at target speeds ranging from 1.0 to 4.5 m/s. Using the novel method, we show that TBV regulation differs between treadmill types, and that certain features of TBV regulation are affected by the subjects’ body mass and their locomotion speed. With higher body mass, the TBV reductions in the braking phase of stance became higher, even though this relationship differed between locomotion speeds and treadmill type (significant body mass × speed × treadmill type interaction). Average belt speeds varied between about 98 and 103% of the target speed. For three of the four treadmills, TBV reduction during the stance phase of running was more intense (> 5% target speed) and occurred earlier (before 50% of stance phase) unlike the typical overground center of mass velocity patterns reported in the literature. Overall, the results of this study emphasize the importance of monitoring TBV during locomotor research and applied diagnostics. We provide a novel method that is freely accessible on Matlab’s file exchange server (“getBeltVelocity.m”) allowing TBV tracking to become standard practice in locomotion research.
Melamine (1,3,5-triazine-2,4,6-triamine or cyanuramide, C3H6N6) is a trimer of cyanamide, with a 1,3,5-triazine skeleton (Figure 3.5-1). The molecule contains 66% nitrogen by mass and, if mixed with resins, has fire retardant properties due to its release of nitrogen gas when burned or charred. The word melamine (from German) is a combination of the word melam (which is a distillation derivative of ammonium thiocyanate) and amine [1]. Melamine is also a metabolite of cyromazine, an insecticide in which the proton of an NH2-group is substituted by a cyclopropyl group.
Electronic pills, smart capsules or miniaturized microsystems swallowed by human beings or animals for various biomedical and diagnostic applications are growing rapidly in the last years. This paper searched out the important existing electronic pills in the market and prototypes in research centers. Further objective of this research is to develop a technology platform with enhanced feature to cover the drawback of most
capsules. The designed telemetry unit is a synchronous bidirectional communication block using continuous phase DQPSK of 115 kHz low carrier frequency for inductive data transmission suited for human body energy transfer. The communication system can assist the electronic pill to trigger an actuator for drug delivery, to record temperature, or to measure pH of the body. It consists additionally to a 32bit processor, memory, external peripheries, and detection facility. The complete system is designed to fit small-size mass medical application with low power consumption, size of 7x25mm. The system is designed, simulated and emulated on FPGA.
In recent years, physically unclonable functions (PUFs) have gained significant attraction in IoT security applications, such as cryptographic key generation and entity authentication. PUFs extract the uncontrollable production characteristics of different devices to generate unique fingerprints for security applications. When generating PUF-based secret keys, the reliability and entropy of the keys are vital factors. This study proposes a novel method for generating PUF-based keys from a set of measurements. Firstly, it formulates the group-based key generation problem as an optimization problem and solves it using integer linear programming (ILP), which guarantees finding the optimum solution. Then, a novel scheme for the extraction of keys from groups is proposed, which we call positioning syndrome coding (PSC). The use of ILP as well as the introduction of PSC facilitates the generation of high-entropy keys with low error correction costs. These new methods have been tested by applying them on the output of a capacitor network PUF. The results confirm the application of ILP and PSC in generating high-quality keys.
A novel peptidyl-lys metalloendopeptidase (Tc-LysN) from Tramates coccinea was recombinantly expressed in Komagataella phaffii using the native pro-protein sequence. The peptidase was secreted into the culture broth as zymogen (~38 kDa) and mature enzyme (~19.8 kDa) simultaneously. The mature Tc-LysN was purified to homogeneity with a single step anion-exchange chromatography at pH 7.2. N-terminal sequencing using TMTpro Zero and mass spectrometry of the mature Tc-LysN indicated that the pro-peptide was cleaved between the amino acid positions 184 and 185 at the Kex2 cleavage site present in the native pro-protein sequence. The pH optimum of Tc-LysN was determined to be 5.0 while it maintained ≥60% activity between pH values 4.5—7.5 and ≥30% activity between pH values 8.5—10.0, indicating its broad applicability. The temperature maximum of Tc-LysN was determined to be 60 °C. After 18 h of incubation at 80 °C, Tc-LysN still retained ~20% activity. Organic solvents such as methanol and acetonitrile, at concentrations as high as 40% (v/v), were found to enhance Tc-LysN’s activity up to ~100% and ~50%, respectively. Tc-LysN’s thermostability, ability to withstand up to 8 M urea, tolerance to high concentrations of organic solvents, and an acidic pH optimum make it a viable candidate to be employed in proteomics workflows in which alkaline conditions might pose a challenge. The nano-LC-MS/MS analysis revealed bovine serum albumin (BSA)’s sequence coverage of 84% using Tc-LysN which was comparable to the sequence coverage of 90% by trypsin peptides.
Governments have restricted public life during the COVID-19 pandemic, inter alia closing sports facilities and gyms. As regular exercise is essential for health, this study examined the effect of pandemic-related confinements on physical activity (PA) levels. A multinational survey was performed in 14 countries. Times spent in moderate-to-vigorous physical activity (MVPA) as well as in vigorous physical activity only (VPA) were assessed using the Nordic Physical Activity Questionnaire (short form). Data were obtained for leisure and occupational PA pre- and during restrictions. Compliance with PA guidelines was calculated based on the recommendations of the World Health Organization (WHO). In total, n = 13,503 respondents (39 ± 15 years, 59% females) were surveyed. Compared to pre-restrictions, overall self-reported PA declined by 41% (MVPA) and 42.2% (VPA). Reductions were higher for occupational vs. leisure time, young and old vs. middle-aged persons, previously more active vs. less active individuals, but similar between men and women. Compared to pre-pandemic, compliance with WHO guidelines decreased from 80.9% (95% CI: 80.3–81.7) to 62.5% (95% CI: 61.6–63.3). Results suggest PA levels have substantially decreased globally during the COVID-19 pandemic. Key stakeholders should consider strategies to mitigate loss in PA in order to preserve health during the pandemic.
In recent years, the topic of embedded machine learning has become very popular in AI research. With the help of various compression techniques such as pruning, quantization and others compression techniques, it became possible to run neural networks on embedded devices. These techniques have opened up a whole new application area for machine learning. They range from smart products such as voice assistants to smart sensors that are needed in robotics. Despite the achievements in embedded machine learning, efficient algorithms for training neural networks in constrained domains are still lacking. Training on embedded devices will open up further fields of applications. Efficient training algorithms would enable federated learning on embedded devices, in which the data remains where it was collected, or retraining of neural networks in different domains. In this paper, we summarize techniques that make training on embedded devices possible. We first describe the need and requirements for such algorithms. Then we examine existing techniques that address training in resource-constrained environments as well as techniques that are also suitable for training on embedded devices, such as incremental learning. At the end, we also discuss which problems and open questions still need to be solved in these areas.
Nowadays decarbonisation of the energy system is one of the main concerns for most governments. Renewable energy technologies, such as rooftop photovoltaic systems and home battery storage systems, are changing the energy system to be more decentralised. As a consequence, new ways of energy business models are emerging, e.g., peer-to-peer energy trading. This new concept provides an online marketplace where direct energy exchange can occur between its participants. The purpose of this study is to conduct a content analysis of the existing literature, ongoing research projects, and companies related to peer-to-peer energy trading. From this review, a summary of the most important aspects and journal papers is assessed, discussed, and classified. It was found that the different energy market types were named in various ways and a proposal for standard language for the several peer-to-peer market types and the different actors involved is suggested. Additionally, by grouping the most important attributes from peer-to-peer energy trading projects, an assessment of the entry barrier and scalability potential is performed by using a characterisation matrix.
A Review on Kinetic Energy Harvesting with Focus on 3D Printed Electromagnetic Vibration Harvesters
(2021)
The increasing amount of Internet of Things (IoT) devices and wearables require a reliable energy source. Energy harvesting can power these devices without changing batteries. Three-dimensional printing allows us to manufacture tailored harvesting devices in an easy and fast way. This paper presents the development of hybrid and non-hybrid 3D printed electromagnetic vibration energy harvesters. Various harvesting approaches, their utilised geometry, functional principle, power output and the applied printing processes are shown. The gathered harvesters are analysed, challenges examined and research gaps in the field identified. The advantages and challenges of 3D printing harvesters are discussed. Reported applications and strategies to improve the performance of printed harvesting devices are presented.
Background: Assistive Robotic Arms are designed to assist physically disabled people with daily activities. Existing joysticks and head controls are not applicable for severely disabled people such as people with Locked-in Syndrome. Therefore, eye tracking control is part of ongoing research. The related literature spans many disciplines, creating a heterogeneous field that makes it difficult to gain an overview.
Objectives: This work focuses on ARAs that are controlled by gaze and eye movements. By answering the research questions, this paper provides details on the design of the systems, a comparison of input modalities, methods for measuring the performance of these controls, and an outlook on research areas that gained interest in recent years.
Methods: This review was conducted as outlined in the PRISMA 2020 Statement. After identifying a wide range of approaches in use the authors decided to use the PRISMA-ScR extension for a scoping review to present the results. The identification process was carried out by screening three databases. After the screening process, a snowball search was conducted.
Results: 39 articles and 6 reviews were included in this article. Characteristics related to the system and study design were extracted and presented divided into three groups based on the use of eye tracking.
Conclusion: This paper aims to provide an overview for researchers new to the field by offering insight into eye tracking based robot controllers. We have identified open questions that need to be answered in order to provide people with severe motor function loss with systems that are highly useable and accessible.
A simple Method for quantifying Triazine Herbicides using Thin-Layer Chromatography and a CCD-Camera
(2010)
We present a video-densitometric quantification method for the triazine herbicides atraton, terbumeton, simazine, atrazine, and terbutylazine. Triazine herbicides were separated on silica gel using methyl-t-butyl ether, cyclohexane (1 + 1, v/v) as mobile phase. The quantification is based on a derivation reaction using chlorine and starch-iodine which forms red-brown triazine zones. Measurements were carried out using a 16 bit ST-1603ME CCD camera with 1.56 megapixel from Santa Barbara Instrument Group, Inc., Santa Barbara, USA. A white LED was used for illumination purposes. The range of linearity covers two magnitudes using the (1/R-1) expression data transformation. The signal-to-noise ratio increases directly linearly with the measurement time. The separation method is cheap, fast and reliable.
In short-reach connections, large-diameter multimode fibres allow for robust and easy connections. Unfortunately, their propagation properties depend on the excitation conditions. We propose a launching technique using a fibre stub that can tolerate fabrication tolerances in terms of tilts and off-sets to a large extent. A study of the influence of displaced connectors along the transmission link shows that the power distributions approach a steady-state power distribution very similar to the initial distribution established by the proposed launching scheme.
Decentralized applications (dApp) have proliferated in recent years, but their long-term viability is a topic of debate. However, for dApps to be sustainable, and suitable for integration into a larger service networks, they need to attract users and promise reliable availability. Therefore, assessing their longevity is crucial. Analyzing the utilization trajectory of a service is, however, challenging due to several factors, such as demand spikes, noise, autocorrelation, and non-stationarity. In this study, we employ robust statistical techniques to identify trends in currently popular dApps. Our findings demonstrate that a significant proportion of dApps, across a range of categories, exhibit statistically significant positive overall trends, indicating that success in decentralized computing can be sustainable and transcends specific fields. However, there is also a substantial number of dApps showing negative trends, with a disproportionately high number from the decentralized finance (DeFi) category. Furthermore, a more detailed inspection of time series segments shows a clearly diminishing proportion of positive trends from mid-2021 to the present. In summary, we conclude that the dApp economy might have lost some momentum, and that there is a strong element of uncertainty regarding its future significance.
The increase of the Internet of Things (IoT) calls for secure solutions for industrial applications. The security of IoT can be potentially improved by blockchain. However, blockchain technology suffers scalability issues which hinders integration with IoT. Solutions to blockchain’s scalability issues, such as minimizing the computational complexity of consensus algorithms or blockchain storage requirements, have received attention. However, to realize the full potential of blockchain in IoT, the inefficiencies of its inter-peer communication must also be addressed. For example, blockchain uses a flooding technique to share blocks, resulting in duplicates and inefficient bandwidth usage. Moreover, blockchain peers use a random neighbor selection (RNS) technique to decide on other peers with whom to exchange blockchain data. As a result, the peer-to-peer (P2P) topology formation limits the effective achievable throughput. This paper provides a survey on the state-of-the-art network structures and communication mechanisms used in blockchain and establishes the need for network-based optimization. Additionally, it discusses the blockchain architecture and its layers categorizes existing literature into the layers and provides a survey on the state-of-the-art optimization frameworks, analyzing their effectiveness and ability to scale. Finally, this paper presents recommendations for future work.
In this paper, a temperature-dependent viscoplasticity model is presented that describes thermal and cyclic softening of the hot work steel X38CrMoV5-3 under thermomechanical fatigue loading. The model describes the softening state of the material by evolution equations, the material properties of which can be determined on the basis of a defined experimental program. A kinetic model is employed to capture the effect of coarsening carbides and a new isotropic cyclic softening model is developed that takes history effects during thermomechanical loadings into account. The temperature-dependent material properties of the viscoplasticity model are determined on the basis of experimental data measured in isothermal and thermomechanical fatigue tests for the material X38CrMoV5-3 in the temperature range between 20 and 650 ∘C. The comparison of the model and an existing model for isotropic softening shows an improved description of the softening behavior under thermomechanical fatigue loading. A good overall description of the experimental data is possible with the presented viscoplasticity model, so that it is suited for the assessment of operating loads of hot forging tools.
Air traffic control today still works primarily with classical sensors like primary and Secondary Surveillance Radars (PSR, MSSR, Mode-S) [1]. Upcoming is a new technology, ADS (Automatic Dependent Surveillance), which derives positional information from a Global Navigation Satellite System (GNSS) and distributes this data together with additional information from the on-board Flight Management System (FMS) to other aircraft (air-to-air) and to ADS groundstations (air-to-ground). [2] Because the transmission of the data takes place on a shared broadcasting media, like the 1090 MHz Extended Squitter (ES) channel, the technology is also referred to as ADS-Broadcast (ADS-B).
Featherweight Generic Go (FGG) is a minimal core calculus modeling the essential features of the programming language Go. It includes support for overloaded methods, interface types, structural subtyping, and generics. The most straightforward semantic description of the dynamic behavior of FGG programs is to resolve method calls based on runtime type information of the receiver. This article shows a different approach by defining a type-directed translation from FGG− to an untyped lambda-calculus. FGG− includes all features of FGG but type assertions. The translation of an FGG− program provides evidence for the availability of methods as additional dictionary parameters, similar to the dictionary-passing approach known from Haskell type classes. Then, method calls can be resolved by a simple lookup of the method definition in the dictionary. Every program in the image of the translation has the same dynamic semantics as its source FGG− program. The proof of this result is based on a syntactic, step-indexed logical relation. The step index ensures a well-founded definition of the relation in the presence of recursive interface types and recursive methods. Although being non-deterministic, the translation is coherent.
We present a densitometric quantification method for triclosan in toothpaste, separated by high-performance thin-layer chromatography (HPTLC) and using a 48-bit flatbed scanner as the detection system. The sample was band-wise applied to HPTLC plates (10 × 20 cm), with fluorescent dye, Merck, Germany (1.05554). The plates were developed in a vertical developing chamber with 20 min of chamber saturation over 70 mm, using n-heptane–methyl tert-butyl ether–acetic acid (92:8:0.1, V/V) as solvent. The RF value of triclosan is hRF = 22.4, and quantification is based on direct measurements using an inexpensive 48-bit flatbed scanner for color measurements (in red, green, and blue) after plate staining with 2,6-dichloroquinone-4-chloroimide (Gibbs' reagent). Evaluation of the red channel makes the measurements of triclosan very specific. For linearization, an extended Kubelka–Munk expression was used for data transformation. The range of linearity covers more than two orders of magnitude and is between 91 and 1000 ng. The separation method is inexpensive, fast and reliable.
The Metering Bus, also known as M-Bus, is a European standard EN13757-3 for reading out metering devices, like electricity, water, gas, or heat meters. Although real-life M-Bus networks can reach a significant size and complexity, only very simple protocol analyzers are available to observe and maintain such networks. In order to provide developers and installers with the ability to analyze the real bus signals easily, a web-based monitoring tool for the M-Bus has been designed and implemented. Combined with a physical bus interface it allows for measuring and recording the bus signals. For this at first a circuit has been developed, which transforms the voltage and current-modulated M-Bus signals to a voltage signal that can be read by a standard ADC and processed by an MCU. The bus signals and packets are displayed using a web server, which analyzes and classifies the frame fragments. As an additional feature an oscilloscope functionality is included in order to visualize the physical signal on the bus. This paper describes the development of the read-out circuit for the Wired M-Bus and the data recovery.
For the treatment of bone defects, biodegradable, compressive biomaterials are needed as replacements that degrade as the bone regenerates. The problem with existing materials has either been their insufficient mechanical strength or the excessive differences in their elastic modulus, leading to stress shielding and eventual failure. In this study, the compressive strength of CPC ceramics (with a layer thickness of more than 12 layers) was compared with sintered β-TCP ceramics. It was assumed that as the number of layers increased, the mechanical strength of 3D-printed scaffolds would increase toward the value of sintered ceramics. In addition, the influence of the needle inner diameter on the mechanical strength was investigated. Circular scaffolds with 20, 25, 30, and 45 layers were 3D printed using a 3D bioplotter, solidified in a water-saturated atmosphere for 3 days, and then tested for compressive strength together with a β-TCP sintered ceramic using a Zwick universal testing machine. The 3D-printed scaffolds had a compressive strength of 41.56 ± 7.12 MPa, which was significantly higher than that of the sintered ceramic (24.16 ± 4.44 MPa). The 3D-printed scaffolds with round geometry reached or exceeded the upper limit of the compressive strength of cancellous bone toward substantia compacta. In addition, CPC scaffolds exhibited more bone-like compressibility than the comparable β-TCP sintered ceramic, demonstrating that the mechanical properties of CPC scaffolds are more similar to bone than sintered β-TCP ceramics.
ABSCHIED VOM AUSSEN
(2019)
In pandemic times, the possibilities for conventional sports activities are severely limited; many sports facilities are closed or can only be used with restrictions. To counteract this lack of health activities and social exchange, people are increasingly adopting new digital sports solutions—a behavior change that had already started with the trend towards fitness apps and activity trackers. Existing research suggests that digital solutions increase the motivation to move and stay active. This work further investigates the potentials of digital sports incorporating the dimensions gender and preference for team sports versus individual sports. The study focuses on potential users, who were mostly younger professionals and academics. The results show that the SARS-CoV-19 pandemic had a significant negative impact on sports activity, particularly on persons preferring team sports. To compensate, most participants use more digital sports than before, and there is a positive correlation between the time spent physically active during the pandemic and the increase in motivation through digital sports. Nevertheless, there is still considerable skepticism regarding the potential of digital sports solutions to increase the motivation to do sports, increase performance, or raise a sense of team spirit when done in groups.
Most recently, the federal government in Germany published new climate goals in order reach climate neutrality by 2045. This paper demonstrates a path to a cost optimal energy supply system for the German power grid until the year 2050. With special regard to regionality, the system is based on yearly myopic optimization with the required energy system transformation measures and the associated system costs. The results point out, that energy storage systems (ESS) are fundamental for renewables integration in order to have a feasible energy transition. Moreover, the investment in storage technologies increased the usage of the solar and wind technologies. Solar energy investments were highly accompanied with the installation of short-term battery storage. Longer-term storage technologies, such as H2, were accompanied with high installations of wind technologies. The results pointed out that hydrogen investments are expected to overrule short-term batteries if their cost continues to decrease sharply. Moreover, with a strong presence of ESS in the energy system, biomass energy is expected to be completely ruled out from the energy mix. With the current emission reduction strategy and without a strong presence of large scale ESS into the system, it is unlikely that the Paris agreement 2° C target by 2050 will be achieved, let alone the 1.5° C.
Active participation of industrial enterprises in electricity markets - a generic modeling approach
(2021)
Industrial enterprises represent a significant portion of electricity consumers with the potential of providing demand-side energy flexibility from their production processes and on-site energy assets. Methods are needed for the active and profitable participation of such enterprises in the electricity markets especially with variable prices, where the energy flexibility available in their manufacturing, utility and energy systems can be assessed and quantified. This paper presents a generic model library equipped with optimal control for energy flexibility purposes. The components in the model library represent the different technical units of an industrial enterprise on material, media, and energy flow levels with their process constraints. The paper also presents a case study simulation of a steel-powder manufacturing plant using the model library. Its energy flexibility was assessed when the plant procured its electrical energy at fixed and variable electricity prices. In the simulated case study, flexibility use at dynamic prices resulted in a 6% cost reduction compared to a fixed-price scenario, with battery storage and the manufacturing system making the largest contributions to flexibility.
In a randomized controlled cross-over study ten male runners (26.7 ± 4.9 years; recent 5-km time: 18:37 ± 1:07 min:s) performed an incremental treadmill test (ITT) and a 3-km time trial (3-km TT) on a treadmill while wearing either carbon fiber insoles with downwards curvature or insoles made of butyl rubber (control condition) in light road racing shoes (Saucony Fastwitch 9). Oxygen uptake, respiratory exchange ratio, heart rate, blood lactate concentration, stride frequency, stride length and time to exhaustion were assessed during ITT. After ITT, all runners rated their perceived exertion, perceived shoe comfort and perceived shoe performance. Running time, heart rate, blood lactate levels, stride frequency and stride length were recorded during, and shoe comfort and shoe performance after, the 3-km TT. All parameters obtained during or after the ITT did not differ between the two conditions [range: p = 0.188 to 0.948 (alpha value: 0.05); Cohen's d = 0.021 to 0.479] despite the rating of shoe comfort showing better scores for the control insoles (p = 0.001; d = −1.646). All parameters during and after the 3-km TT showed no differences (p = 0.200 to 1.000; d = 0.000 to 0.501) between both conditions except for shoe comfort showing better scores for control insoles (p = 0.017; d = −0.919). Running with carbon fiber insoles with downwards curvature did not change running performance or any submaximal or maximal physiological or biomechanical parameter and perceived exertion compared to control condition. Shoe comfort is impaired while running with carbon fiber insoles. Wearing carbon fiber insoles with downwards curvature during treadmill running is not beneficial when compared to running with control insoles.
Blockchain-IIoT integration into industrial processes promises greater security, transparency, and traceability. However, this advancement faces significant storage and scalability issues with existing blockchain technologies. Each peer in the blockchain network maintains a full copy of the ledger which is updated through consensus. This full replication approach places a burden on the storage space of the peers and would quickly outstrip the storage capacity of resource-constrained IIoT devices. Various solutions utilizing compression, summarization or different storage schemes have been proposed in literature. The use of cloud resources for blockchain storage has been extensively studied in recent years. Nonetheless, block selection remains a substantial challenge associated with cloud resources and blockchain integration. This paper proposes a deep reinforcement learning (DRL) approach as an alternative to solving the block selection problem, which involves identifying the blocks to be transferred to the cloud. We propose a DRL approach to solve our problem by converting the multi-objective optimization of block selection into a Markov decision process (MDP). We design a simulated blockchain environment for training and testing our proposed DRL approach. We utilize two DRL algorithms, Advantage Actor-Critic (A2C), and Proximal Policy Optimization (PPO) to solve the block selection problem and analyze their performance gains. PPO and A2C achieve 47.8% and 42.9% storage reduction on the blockchain peer compared to the full replication approach of conventional blockchain systems. The slowest DRL algorithm, A2C, achieves a run-time 7.2 times shorter than the benchmark evolutionary algorithms used in earlier works, which validates the gains introduced by the DRL algorithms. The simulation results further show that our DRL algorithms provide an adaptive and dynamic solution to the time-sensitive blockchain-IIoT environment.
Deutschland hat nicht zuletzt durch seine zentrale Lage eine führende Rolle im Bereich der Transportlogistik in Europa übernommen. Allerdings stehen die großen Logistikunternehmen in den letzten Jahren zunehmend vor neuen Herausforderungen. Zum einen steigt die Menge zu transportierender Güter jährlich, zum anderen entstanden durch Verschmelzungen großer Logistikunternehmen wie z. B. Deutsche Post, Danzas und Exel, UPS und Fritz riesige Fahrzeugflotten, deren effiziente Planung die Unternehmen vor enorme Probleme stellt. Die einzige Möglichkeit, diese meist heterogenen, also aus vielen verschiedenen Verkehrsmitteln bestehenden Flotten mit herkömmlichen Mitteln effizient zu planen, ist die Aufteilung in (regionale) Geschäftsbereiche. Dadurch können viele Synergieeffekte nicht genutzt werden, was unter anderem zu unnötig hohen Transportkilometerleistungen und Leerfahrten führt. Mit Hilfe agentenbasierter Systeme können heute schon Kosteneinsparungen von 3 – 6 % bei homogenen Verkehrsmitteln erzielt werden. Das Einsparpotenzial dürfte bei heterogenen Flotten ähnlich hoch, wenn nicht noch etwas höher sein. Allerdings liefern derzeit agentenbasierte Systeme für heterogene Flotten noch keine zufriedenstellenden Ergebnisse. Durch die Kombination der beiden vorrangig für die Transportoptimierung eingesetzten Techniken agentenbasierte (bottomup) Optimierung und der klassischen (topdown)Optimierung soll auch das Einsparpotenzial von heterogenen Flotten realisiert werden. Diese Optimierung ist Gegenstand des Attractive Forschungsprojekts, das von August 2009 bis Juli 2012 im Rahmen des Programms ingenieurNachwuchs gefördert wird.
The significant market growth of stationary electrical energy storage systems both for private and commercial applications has raised the question of battery lifetime under practical operation conditions. Here, we present a study of two 8 kWh lithium-ion battery (LIB) systems, each equipped with 14 lithium iron phosphate/graphite (LFP) single cells in different cell configurations. One system was based on a standard configuration with cells connected in series, including a cell-balancing system and a 48 V inverter. The other system featured a novel configuration of two stacks with a parallel connection of seven cells each, no cell-balancing system, and a 4 V inverter. The two systems were operated as part of a microgrid both in continuous cycling mode between 30% and 100% state of charge, and in solar-storage mode with day–night cycling. The aging characteristics in terms of capacity loss and internal resistance change in the cells were determined by disassembling the systems for regular checkups and characterizing the individual cells under well-defined laboratory conditions. As a main result, the two systems showed cell-averaged capacity losses of 18.6% and 21.4% for the serial and parallel configurations, respectively, after 2.5 years of operation with 810 (serial operation) and 881 (parallel operation) cumulated equivalent full cycles. This is significantly higher than the aging of a reference single cell cycled under laboratory conditions at 20 °C, which showed a capacity loss of only 10% after 1000 continuous full cycles.
Allgemeine Geschäftsbedingungen als Instrument der Vereinfachung betrieblicher Vertragsgestaltung
(2018)
Im Wirtschaftsleben spielen heute AGB eine bedeutende Rolle. Diese sind nach § 305 Abs. 1 BGB alle, für eine Vielzahl von Verträgen vorformulierten Vertragsbedingungen, die eine Vertragspartei (Verwender) der anderen Vertragspartei bei Abschluss eines Vertrags stellt. Vertragsbedingungen sind dabei die Regelungen, die Bestandteil des Vertrages werden sollen.1 Gleichgültig ist, ob die Bestimmungen einen äußerlich gesonderten Bestandteil des Vertrags bilden oder in die Vertragsurkunde selbst aufgenommen werden, welchen Umfang sie aufweisen, in welcher Schriftart sie verfasst sind und welche Form der Vertrag hat (vgl. § 305 Abs. 1 S. 2 BGB). Durch AGB wird grundsätzlich ein Rationalisierungseffekt erreicht. Bei Abschluss von Massenverträgen stellen diese eine Vereinfachung der Vertragsabwicklung dar. Stetig gleichbleibende Vertragsregelungen können einmalig formuliert und ständig wiederverwendet werden. Des Weiteren verfolgen AGB den Zweck, das Risiko ihres Verwenders zu begrenzen. AGB stellen ebenso Regelungen des Rechtsverhältnisses zwischen den Vertragsparteien dar. Neben den Vorteilen, können sich aber auch nachteilige Aspekte für den Verwender ergeben. Durch die Vorformulierung von AGB kann die Gefahr bestehen, dass der AGB-Verwender die Regelungen ausschließlich zu seinen Gunsten und damit zum Nachteil der anderen Vertragspartei gestaltet. In einer Drucksituation kann die Gegenseite des Vertrages so gezwungen sein, sich mit den AGB als einverstanden zu erklären. Als Beispiel kann der AGB-Verwender eine Monopolstellung innehaben oder die andere Vertragspartei benötigt die Vertragsleistung dringend.
In the literature, many studies have described the 3D printing of ceramic-based scaffolds (e.g., printing with calcium phosphate cement) in the form of linear structures with layer rotations of 90°, although no right angles can be found in the human body. Therefore, this work focuses on the adaptation of biological shapes, including a layer rotation of only 1°. Sample shapes were printed with calcium phosphate cement using a 3D Bioplotter from EnvisionTec. Both straight and wavy spokes were printed in a round structure with 12 layers. Depending on the strand diameter (200 and 250 µm needle inner diameter) and strand arrangement, maximum failure loads of 444.86 ± 169.39 N for samples without subsequent setting in PBS up to 1280.88 ± 538.66 N after setting in PBS could be achieved.
Im Rahmen dieser Arbeit wird ein „lowcost“ System für smarthome-Anwendungen vorgestellt. Die Steuerung der smarthome-Komponenten erfolgt durch einen Appliance-Controller auf Basis des FS20 Protokolls, wogegen die „Intelligenz“ des Systems durch eine mobile Anwendung (Android-OS) realisiertwird. Durch Auslagerung der Rechenleistung und der Benutzerschnittstelle auf das smartphone kann eine kostengünstige Alternative zur bestehenden Smarthome-Systemen aufgezeigt werden, die durch Einbindung externer Anwendungen leicht erweitert werden kann.
This paper has the objective of creating a framework for a different cultural dimension of corporate entrepreneurship leading to corporate entrepreneurial culture (CEC). The analysis of CEC is based on a review of existing concepts of organisational culture and entrepreneurship. They are combined to create a framework of CEC, including macro- and microlevels and examples of subcultures. Core ideas of the framework are validated by qualitative interviews with ten experts. The identified organisational category of the CEC framework is defined by the levels of micro-cultures or subcultures and includes the upper levels of the hierarchy, including the industry level. Geographic categories such as regional or national culture are also part of the system. The individual category of the CEC framework is characterised by competencies (including aspects such as motivation, creativity, mobilising others, coping with uncertainty, teamwork and social competencies) and entrepreneurial personalities. The results of the interviews show the importance of these individual competencies for a lively CEC. The different levels, such as national and professional cultures, as a dimension of the organisational category of the framework are also confirmed by the interviews. The findings indicate that the individual category of CEC could be used for job satisfaction or engagement and the degree of CEC of an organisation could be defined and developed by the organisational category. The identified framework contributes to an understanding of this complex topic and supports companies in the implementation of entrepreneurial ideas in different organisational contexts.
A coordinated operation of decentralised micro-scale hybrid energy systems within a locally managed network such as a district or neighbourhood will play a significant role in the sector-coupled energy grid of the future. A quantitative analysis of the effects of the primary energy factors, energy conversion efficiencies, load profiles, and control strategies on their energy-economic balance can aid in identifying important trends concerning their deployment within such a network. In this contribution, an analysis of the operational data from five energy laboratories in the trinational Upper-Rhine region is evaluated and a comparison to a conventional reference system is presented. Ten exemplary data-sets representing typical operation conditions for the laboratories in different seasons and the latest information on their national energy strategies are used to evaluate the primary energy consumption, CO2 emissions, and demand-related costs. Various conclusions on the ecologic and economic feasibility of hybrid building energy systems are drawn to provide a toe-hold to the engineering community in their planning and development.
An in-depth study of U-net for seismic data conditioning: Multiple removal by moveout discrimination
(2024)
Seismic processing often involves suppressing multiples that are an inherent component of collected seismic data. Elaborate multiple prediction and subtraction schemes such as surface-related multiple removal have become standard in industry workflows. In cases of limited spatial sampling, low signal-to-noise ratio, or conservative subtraction of the predicted multiples, the processed data frequently suffer from residual multiples. To tackle these artifacts in the postmigration domain, practitioners often rely on Radon transform-based algorithms. However, such traditional approaches are both time-consuming and parameter dependent, making them relatively complex. In this work, we present a deep learning-based alternative that provides competitive results, while reducing the complexity of its usage, and, hence simplifying its applicability. Our proposed model demonstrates excellent performance when applied to complex field data, despite it being exclusively trained on synthetic data. Furthermore, extensive experiments show that our method can preserve the inherent characteristics of the data, avoiding undesired oversmoothed results, while removing the multiples from seismic offset or angle gathers. Finally, we conduct an in-depth analysis of the model, where we pinpoint the effects of the main hyperparameters on real data inference, and we probabilistically assess its performance from a Bayesian perspective. In this study, we put particular emphasis on helping the user reveal the inner workings of the neural network and attempt to unbox the model.
The aim of this paper is to identify indicators at country level that could prove useful in improving the effectiveness of fraud detection in European Structural and Investment Funds. We analyse data for 454 funds, belonging to the period 2014-2020, from the 28 countries that were members of the European Union in 2014. Explanatory results suggest the convenience of tracking funds, especially in countries with higher GDP and higher transparency levels, and the lesser relevance of the number of irregularities for countries with higher GDP and those receiving larger funds. Fraud and fraud detection rates in individual funds vary significantly across states. Federal states, such as the Federal Republic of Germany, are comparatively successful in detecting fraud in EU funds.
An Overview of Technologies for Improving Storage Efficiency in Blockchain-Based IIoT Applications
(2022)
Since the inception of blockchain-based cryptocurrencies, researchers have been fascinated with the idea of integrating blockchain technology into other fields, such as health and manufacturing. Despite the benefits of blockchain, which include immutability, transparency, and traceability, certain issues that limit its integration with IIoT still linger. One of these prominent problems is the storage inefficiency of the blockchain. Due to the append-only nature of the blockchain, the growth of the blockchain ledger inevitably leads to high storage requirements for blockchain peers. This poses a challenge for its integration with the IIoT, where high volumes of data are generated at a relatively faster rate than in applications such as financial systems. Therefore, there is a need for blockchain architectures that deal effectively with the rapid growth of the blockchain ledger. This paper discusses the problem of storage inefficiency in existing blockchain systems, how this affects their scalability, and the challenges that this poses to their integration with IIoT. This paper explores existing solutions for improving the storage efficiency of blockchain–IIoT systems, classifying these proposed solutions according to their approaches and providing insight into their effectiveness through a detailed comparative analysis and examination of their long-term sustainability. Potential directions for future research on the enhancement of storage efficiency in blockchain–IIoT systems are also discussed.
An Ultra-Low-Power RFID/NFC Frontend IC Using 0.18 μm CMOS Technology for Passive Tag Applications
(2018)
Battery-less passive sensor tags based on RFID or NFC technology have achieved much popularity in recent times. Passive tags are widely used for various applications like inventory control or in biotelemetry. In this paper, we present a new RFID/NFC frontend IC (integrated circuit) for 13.56 MHz passive tag applications. The design of the frontend IC is compatible with the standard ISO 15693/NFC 5. The paper discusses the analog design part in details with a brief overview of the digital interface and some of the critical measured parameters. A novel approach is adopted for the demodulator design, to demodulate the 10% ASK (amplitude shift keying) signal. The demodulator circuit consists of a comparator designed with a preset offset voltage. The comparator circuit design is discussed in detail. The power consumption of the bandgap reference circuit is used as the load for the envelope detection of the ASK modulated signal. The sub-threshold operation and low-supply-voltage are used extensively in the analog design—to keep the power consumption low. The IC was fabricated using 0.18 μm CMOS technology in a die area of 1.5 mm × 1.5 mm and an effective area of 0.7 mm2. The minimum supply voltage desired is 1.2 V, for which the total power consumption is 107 μW. The analog part of the design consumes only 36 μW, which is low in comparison to other contemporary passive tags ICs. Eventually, a passive tag is developed using the frontend IC, a microcontroller, a temperature and a pressure sensor. A smart NFC device is used to readout the sensor data from the tag employing an Android-based application software. The measurement results demonstrate the full passive operational capability. The IC is suitable for low-power and low-cost industrial or biomedical battery-less sensor applications. A figure-of-merit (FOM) is proposed in this paper which is taken as a reference for comparison with other related state-of-the-art researches.
Im Rahmen dieses Projekts wurde im Labor Telekommunikationstechnik der Hochschule Offenburg ein flexibel konfigurierbares Funknetz nach dem ZigBee-Standard aufgebaut. Mit Hilfe diverser Messgeräte und Analyse-Tools wurden die wesentlichen Performance Parameter dieses Funknetzes unter realen Betriebsbedingungen evaluiert. So wurden z.B. Erkenntnisse über die Empfängerempfindlichkeit, die effektiv erreichbare Datenrate sowie das Interferenzpotential gewonnen, die Voraussetzungen für die optimale Nutzung dieser neuen Funktechnologie sind.
„Die Reform kommt – stirbt das Netz?“ So titelte die Süddeutsche Zeitung bereits Mitte April 2019 in Bezug auf die sich anbahnende Urheberrechtsreform. Kaum ein anderes Rechtsgebiet ist derzeit so präsent in der Mitte der Gesellschaft angekommen und löst derart hitzige Diskussionen aus wie die anstehende Urheberrechtsreform durch den europäischen Gesetzgeber. Dabei ist es der Urheberrechtsreform in der Tat gelungen, einen ähnlichen Stellenwert für sich zu vereinnahmen wie die Einführung der lange gefürchteten Datenschutz-Grundverordnung im Jahr 2018.
Im Fokus der Debatte steht dabei insbesondere Artikel 13, der sich mittlerweile als Artikel 17 in der aktuellen Fassung der Richtlinie wiederfindet. Seine breite Aufmerksamkeit verdankt dieser dem Umstand, dass er die Meinungsfreiheit und die freie Netzkultur in erheblichem Maße einschränken könnte. Allerdings geht die gesamte Richtlinie des europäischen Gesetzgebers deutlich über Artikel 17 hinaus, sodass sich neben der breiten Bevölkerung auch weitere Adressaten ergeben, deren Rahmenbedingungen sich ändern werden.
Im Rahmen dieses Projekts wurde im Labor Telekommunikationstechnik der Hochschule Offenburg die Übertragungsqualität von Mehrantennensystemen durch theoretische Analysen und Simulationen analysiert. Dabei zeigt sich bereits in der ersten Projektphase bei einfachen Mehrantennenkonfigurationen mit einer Sendeantenne und mehreren Empfangsantennen wie aufgrund von Antennendiversität bei verschiedenen Kombinationsstrategien der Empfangssignale sich die Übertragungsqualität bei Rayleigh Fading deutlich verbessert.
Mehrantennensysteme (MIMO: MultipleInputMultipleOutput) sind seit einigen Jahren ein zentrales Forschungsthema in der Funkkommunikation. Die Analyse der Kanalkapazität solcher MIMOSysteme in [1] hat gezeigt, welches enorme Potenzial in dieser Technologie steckt. Dieses Potenzial kann auf verschiedene Arten genutzt werden. MIMOVerfahren können grundsätzlich in zwei Klassen eingeteilt werden. Die erste Klasse besteht aus Verfahren, die die Zuverlässigkeit der Übertragung über FadingKanäle verbessert. Dies wird entweder durch Verbesserung des jeweils wirksamen mittleren SNR (engl. SignaltoNoise power ratio) z. B. durch Beamforming oder durch Verminderung der Fluktuationen des SNR durch Diversitätstechniken erreicht. Die zweite Klasse bilden Verfahren, bei denen mehrere unabhängige Datenströme parallel über die verschiedenen Antennen durch räumliches Multiplexen (engl. Spatial Multiplexing) übertragen und so die Datenrate vervielfacht wird. Während bei den Diversitätstechniken und den Verfahren des Spatial Multiplexing die Übertragungseigenschaften zwischen den verschiedenen Sende- und Empfangsantennen durch z. B. ausgeprägte Mehrwegeausbreitung möglichst unkorreliert sein sollen, ist dies bei den Beamforming-Verfahren aber gerade nicht dienlich. Im Rahmen dieses Projekts wurde die Übertragungsqualität von Funksystemen mit MIMOArchitektur analysiert, die spezielle blockbasierte Codierungsverfahren verwenden, die nicht nur die zeitliche, sondern auch die räumliche Dimension zu der Informationsübertragung nutzen (SpaceTimeBlockCoding, STBC) und damit auf einen Diversitätsgewinn abzielen.
Over the last few decades, several grid coupling techniques for hierarchically refined Cartesian grids have been developed to provide the possibility of varying mesh resolution in lattice Boltzmann methods. The proposed schemes can be roughly categorized based on the individual grid transition interface layout they are adapted to, namely cell-vertex or cell-centered approaches, as well as a combination of both. It stands to reason that the specific properties of each of these grid-coupling algorithms influence the stability and accuracy of the numerical scheme. Consequently, this naturally leads to a curiosity regarding the extent to which this is the case. The present study compares three established grid-coupling techniques regarding their stability ranges by conducting a series of numerical experiments for a square duct flow, including various collision models. Furthermore the hybrid-recursive regularized collision model, originally introduced for cell-vertex algorithms with co-located coarse and fine grid nodes, has been adapted to cell-centered and combined methods.
The mobile devices related industries are subject to rapid change, driven by technological advances and dynamic consumer behaviour. Hence, the understanding of the mobile devices markets is an important step in the analysis phase of mobile applications development. In this paper, a brief description of the different markets is introduced followed by an analysis of the main features of the markets leaders' devices which are important in the development process of mobile web applications. Finally, approaches are proposed to deal with the mobile devices diversity.
Photovoltaic-heat pump (PV-HP) combinations with battery and energy management systems are becoming increasingly popular due to their ability to increase the autarchy and utilization of self-generated PV electricity. This trend is driven by the ongoing electrification of the heating sector and the growing disparity between growing electricity costs and reducing feed-in tariffs in Germany. Smart control strategies can be employed to control and optimize the heat pump operation to achieve higher self-consumption of PV electricity. This work presents the evaluation results of a smart-grid ready controlled PV-HP-battery system in a single-family household in Germany, using 1-minute-high-resolution field measurement data. Within 12 months evaluation period, a self-consumption of 43% was determined. The solar fraction of the HP amounts to 36%, enabled also due to higher set temperatures for space heating and domestic hot water production. Accordingly, the SPF decreases by 4.0% the space heating and by 5.7% in the domestic hot water mode. The combined seasonal performance factor for the heat pump system increases from 4.2 to 6.7, when only considering the electricity taken from the grid and disregarding the locally generated electricity supplied from photovoltaic and battery units.
Die Globalisierung, der technische Fortschritt, sowie die politischen Entwicklungen weltweit führen dazu, dass heute kaum ein Unternehmen existiert, das nicht internationale Geschäftsbeziehungen mit ausländischen Unternehmen aufrecht erhält, unabhängig davon, ob als Exporteur oder Importeur. Grenzüberschreitend tätige Unternehmen sehen sich dabei fremden Rechtsordnungen gegenüberstehend. Dies kann Konflikte mit sich bringen und den Handelsverkehr beeinträchtigen. Dabei stellen neben unterschiedlichen Rechtssystemen auch die kulturellen Differenzen und die räumliche Distanz der beteiligten Länder Hindernisse dar. Zumindest auf dem Gebiet der Gesetzgebung gab es Bemühungen nach Vereinheitlichung. So kam das Übereinkommen der Vereinten Nationen über Verträge über den internationalen Warenkauf, kurz UN-Kaufrecht, das den internationalen Warenhandel vereinfachen soll, zustande. Dieses Regelwerk, sowie die Analyse möglicher Vorteile für den deutschen Exporteur sind Thema dieses Arbeitspapieres. Dabei soll die Analyse nicht nur auf der Literaturrecherche beruhen, sondern sich auch damit auseinandersetzen, wie die Handhabung des UN-Kaufrechts in der Praxis durch Unternehmen erfolgt.
Applied Information Technology opens Virtual Platform for the Legacy of Alexander von Humboldt
(2011)
The Humboldt Digital Library (HDL) is a project that aims to provide digital access to the legacy of Alexander von Humboldt. The HDL runs on an open source library developed in the Hochschule Offenburg and provides a virtual research environment in which researchers can work more effectively. This article presents the development made in the HDL to provide alternative ways of content dissemination through the OAI protocol.Through the implemtantion of the OAI-PMH data provider in the HDL, the library is accessibly in many universities and research centers everywhere around the globe.
Appraising the Methodological Quality of Sports Injury Video Analysis Studies: The QA-SIVAS Scale
(2023)
Background
Video analysis (VA) is commonly used in the assessment of sports injuries and has received considerable research interest. Until now, no tool has been available for the assessment of study quality. Therefore, the objective of this study was to develop and evaluate a valid instrument that reliably assesses the methodological quality of VA studies.
Methods
The Quality Appraisal for Sports Injury Video Analysis Studies (QA-SIVAS) scale was developed using a modified Delphi approach including expert consensus and pilot testing. Reliability was examined through intraclass correlation coefficient (ICC3,1) and free-marginal kappa statistics by three independent raters. Construct validity was investigated by comparing QA-SIVAS with expert ratings by using Kendall’s tau analysis. Rating time was studied by applying the scale to 21 studies and computing the mean time for rating per study article.
Results
The QA-SIVAS scale consists of an 18-item checklist addressing the study design, data source, conduct, report, and discussion of VA studies in sports injury research. Inter- and intra-rater reliability were excellent with ICCs > 0.97. Expert ratings revealed a high construct validity (0.71; p < 0.001). Mean rating time was 10 ± 2 min per article.
Conclusion
QA-SIVAS is a reliable and valid instrument that can be easily applied to sports injury research. Future studies in the field of VA should adhere to standardized methodological criteria and strict quality guidelines.
Um sicherzustellen, dass vom Unternehmen keine Verstöße gegen gesetzliche Vorschriften und Regeln erfolgen, ist es unabdingbar, dass die Mitarbeiter des Unternehmens den aufgestellten Pflichten nachkommen und diese befolgen. Dabei kann dies nur verwirklicht werden, wenn die Regelungen für die Arbeitnehmer verbindlich werden und bei Fehlverhalten auch arbeitsrechtliche Sanktionen als Konsequenz durchgesetzt werden können. Damit die Verhaltensrichtlinien und -grundsätze für die Arbeitnehmer verbindlich werden, müssen diese arbeitsrechtlich im Unternehmen implementiert werden. Die Implementierung kann dabei grundsätzlich durch unterschiedliche arbeitsrechtliche Instrumente umgesetzt werden, wobei sowohl das Individual- als auch das Kollektivarbeitsrecht verschiedene Optionen anbietet, welche im Folgenden näher erläutert werden.
Im Institut für Angewandte Forschung (IAF) der Hochschule Offenburg, im ASIC-Design-Center wird seit Jahren an einem Softcore, genannt SIRIUS (Small Imprint Risc for ubi quitions System), entwickelt, der sich inzwischen in drei Familienmitglieder aufteilt: SIRIUS-TINY mit einer internen 16-bit-Struktur und einem 16-bit-Adressraum als kleinen Bruder, dem SIRIUS-JANUS mit einer internen 32-bit-Struktur, aber einem 16-bit-Bus-System, das es erlaubt den 32-bit-Adressraum zu nutzen, und dem großen Bruder, dem SIRIUS-HULK der sowohl intern als auch extern über eine 32-bit-Struktur verfügt, zusätzlich einen 32-bit-Divider enthält und auf den Speicher über einen dualen Cache zugreift.
Young female handball players represent a high-risk population for anterior cruciate ligament (ACL) injuries. While the external knee abduction moment (KAM) is known to be a risk factor, it is unclear how cutting technique affects KAMs in sport-specific cutting maneuvers. Further, the effect of added game specificity (e.g., catching a ball or faking defenders) on KAMs and cutting technique remains unknown. Therefore, this study aimed: (i) to test if athletes grouped into different clusters of peak KAMs produced during three sport-specific fake-and-cut tasks of different complexities differ in cutting technique, and (ii) to test whether technique variables change with task complexity. Fifty-one female handball players (67.0 ± 7.7 kg, 1.70 ± 0.06 m, 19.2 ± 3.4 years) were recruited. Athletes performed at least five successful handball-specific sidestep cuts of three different complexities ranging from simple pre-planned fake-and-cut maneuvers to catching a ball and performing an unanticipated fake-and-cut maneuver with dynamic defenders. A k-means cluster algorithm with squared Euclidean distance metric was applied to the KAMs of all three tasks. The optimal cluster number of koptimal = 2 was calculated using the average silhouette width. Statistical differences in technique variables between the two clusters and the tasks were analyzed using repeated-measures ANOVAs (task complexity) with nested groupings (clusters). KAMs differed by 64.5%, on average, between clusters. When pooling all tasks, athletes with high KAMs showed 3.4° more knee valgus, 16.9% higher downward and 8.4% higher resultant velocity at initial ground contact, and 20.5% higher vertical ground reaction forces at peak KAM. Unlike most other variables, knee valgus angle was not affected by task complexity, likely due to it being part of inherent movement strategies and partly determined by anatomy. Since the high KAM cluster showed higher vertical center of mass excursions and knee valgus angles in all tasks, it is likely that this is part of an automated motor program developed over the players' careers. Based on these results, reducing knee valgus and downward velocity bears the potential to mitigate knee joint loading and therefore ACL injury risk.
Aus Ideen werden Produkte
(2020)
Auswirkung eines Importstopps russischer Energieträger auf die Klimaschutzziele in Deutschland
(2022)
Ein Importstopp russischer Energieträger nach Deutschland wird derzeit vermehrt diskutiert. Wir wollen die Diskussion unterstützen, indem wir einen Weg zeigen, wie das Elektrizitätssystem in Deutschland kurzfristig mit geringen Energieimporten auskommt und welche Maßnahmen notwendig sind, um die Klimaschutzziele trotzdem einzuhalten. Die Ergebnisse eines solchen Energiewendeszenarios mit reduzierter Importabhängigkeit werden mit dem Energiesystemmodell MyPyPSA-Ger berechnet. Die wichtigsten Erkenntnisse sind, dass ein zügiger Ausbau Erneuerbarer Energien und von Speichertechnologien • die Abhängigkeit des deutschen Elektrizitätssystems von Energieimporten deutlich reduziert. • auch langfristig keine wesentlichen Importe der Energieträger Erdgas, Steinkohle und Mineralöl nach sich zieht. • über die Klimaziele der Bundesregierung hinaus das 1,5-Grad-Ziel im Elektrizitätssystem erreicht wird.
Authentic corporate social responsibility: antecedents and effects on consumer purchase intention
(2023)
Purpose
The aim of the research is to identify the factors that create an authentic company's corporate social responsibility (CSR) engagement and to investigate whether an authentic CSR engagement influences the purchase intention. In addition, the study attempts to provide insights into the mediation role of attitude toward the company and frequency of purchase on purchase intention.
Design/methodology/approach
In this study, a theoretical framework is developed in which major antecedents of authentic CSR are identified. A specific example of a brand and its corporate social responsibility activities was used for the study. An online questionnaire was used to collect the data. To verify the hypothesis, structural equation modeling with the partial least squares method was used. A total of 240 people participated in the study.
Findings
The results of the study confirmed that CSR authenticity positively influences consumer purchase intention. Furthermore, the hypothesized impact of CSR authenticity on attitudes toward the company and frequency of purchase could be verified.
Originality/value
Although there is research on the antecedents influencing the consumer's perceived authenticity of CSR, it has not addressed differences in impact and has not presented a full picture of influencing antecedents. In addition, CSR proof as a new antecedent is investigated in the study. Moreover, research on outcomes of perceived CSR authenticity still lacks depth. The study therefore addresses this research gap by providing an extensive research framework including antecedents influencing CSR authenticity and outcomes of CSR authenticity.
Schulgebäude im Liegenschaftsbestand vieler Kommunen treten in den vergangenen Jahren immer stärker ins Interesse der Öffentlichkeit. Viele der Gebäude stammen aus den 70-er oder 80-er Jahren und stehen im Rahmen der Bestandserhaltung für Modernisierungsmaßnahmen an. Insbesondere die hohen Betriebskosten für die Heizung hatten bisher Maßnahmen für den winterlichen Wärmeschutz in den Vordergrund gestellt. Die verstärkt auftretenden sommerlichen Extremtemperaturen an Unterrichtstagen der vergangenen Jahre zeigen zudem einen Handlungsbedarf im Bereich des sommerlichen Wärmeschutzes auf. Für die Aufgaben des Gebäudemanagements und zur Umsetzung eines energieeffizienten Gebäudebetriebs zeigen sich immer stärker die Vorteile einer vielseitig einsetzbaren Gebäudeautomation, die über zentrale Stellen des FM (z.B. Technisches Rathaus) zugänglich ist.
Ziel des Pilotprojektes EnMa-HAW ist die Erarbeitung und Erprobung technisch und organisatorisch übertragbarer Konzepte für ein automationsgestütztes Energiemanagement an allen Hochschulen für angewandte Wissenschaften im Land Baden-Württemberg. Das Energiemanagement wird technisch mittels Messtechnik, Datenerfassung, Datenspeicherung und Visualisierung umgesetzt und organisatorisch mit einem Energiezirkel in den Hochschulen verankert.
An der Hochschule Offenburg wird ein autonomer Hubschrauber entwickelt. Die Zelle besteht aus einem kommerziellen Modellhubschrauber Typ Align TREX 600. Als Antrieb dient ein bürstenloser 1.6-kW-Elektromotor mit ca. 40.000 U/min, der von einem 22-V-Lithium-Polymer-Akkumulator mit 5 Ah Speicherkapazität gespeist wird. Das Abfluggewicht des Hubschraubers beträgt ca. 3 kg. Sein Hauptrotor ist ein Zweiblattrotor mit Bell-Hiller-Mechanik. Der Heckrotor wird über einen Zahnriemen von der Hauptrotorwelle abgehend angetrieben. Der Hubschrauber ist autorotationsfähig. <br>Für die Flugregelung wurde ein Kurs-Lagereferenzsystem entwickelt. Die eigentliche Flugregelung sowie die Datenerfassung der Sensoren erfolgt über zwei Atmega128-Mikroprozessoren. Der Hubschrauber ist mit einem Datenlink über Bluetooth mit einem PC am Boden verbunden.
Building energy management systems (BEMSs), dedicated to sustainable buildings, may have additional duties, such as hosting efficient energy management systems (EMSs) algorithms. This duty can become crucial when operating renewable energy sources (RES) and eventual electric energy storage systems (ESSs). Sophisticated EMS approaches that aim to manage RES and ESSs in real time may need high computing capabilities that BEMSs typically cannot provide. This article addresses and validates a fuzzy logic-based EMS for the optimal management of photovoltaic (PV) systems with lead-acid ESSs using an edge computing technology. The proposed method is tested on a real smart grid prototype in comparison with a classical rule-based EMS for different weather conditions. The goal is to investigate the efficacy of islanding the building local network as a control command, along with ESS power control. The results show the implementation feasibility and performance of the fuzzy algorithm in the optimal management of ESSs in both operation modes: grid-connected and islanded modes.
In this paper, we study the runtime performance of symmetric cryptographic algorithms on an embedded ARM Cortex-M4 platform. Symmetric cryptographic algorithms can serve to protect the integrity and optionally, if supported by the algorithm, the confidentiality of data. A broad range of well-established algorithms exists, where the different algorithms typically have different properties and come with different computational complexity. On deeply embedded systems, the overhead imposed by cryptographic operations may be significant. We execute the algorithms AES-GCM, ChaCha20-Poly1305, HMAC-SHA256, KMAC, and SipHash on an STM32 embedded microcontroller and benchmark the execution times of the algorithms as a function of the input lengths.
Im vorliegenden Beitrag werden verschiedene Methoden für den Entwurf eines Stromreglers für pulsweitenmoduliert betriebene Drehstromantriebe beschrieben und miteinander verglichen. In den Vergleich eingeschlossen sind sowohl zeitkontinuierlich entworfene PI-Regler mit klassischer Entkopplung als auch zeitdiskret entworfene PI-Regler mit weiterentwickelter Entkopplung und zeitdiskret entworfene Zustandsregler. Der Fokus liegt dabei auf der Entkopplung der d- und q-Komponente des Statorstromraumzeigers, auch bei hoher Statorfrequenz oder geringer Schaltfrequenz. Es wird gezeigt, dass die Heranziehung von zeitdiskreten Motormodellen und ein darauf basierender Reglerentwurf mit größer werdendem Quotient aus Statorfrequenz und Schaltfrequenz zunehmend Vorteile bietet.
Die Hochschule Offenburg begleitet seit Juli 2006 in Zusammenarbeit mit dem Fraunhofer ISE in Freiburg und der HfT Stuttgart die Solar unterstützte Klimatisierung der Festo AG & Co. KG in Esslingen. Die Anlage wurde im Rahmen des Forschungsvorhabens Solarthermie-2000plus vom Bundesumweltministerium gefördert. Dabei wurde die bereits bestehende Adsorptionskälteanlage, die bisher mit Kompressorenabwärme und Gaskesseln betrieben wurde, durch eine Betriebsanalyse und energetische Bewertung einer solarthermischen Anlage zur Unterstützung der Kälteversorgung eines Büro- und Verwaltungsgebäudes Solaranlage als dritter Wärmelieferant ergänzt.
Beuys-Gespräch
(2022)
Bio, vegan – oder was?
(2023)
Nachhaltigkeit als gesellschaftlicher Wert beeinflusst auch die Haltung der Konsumierenden gegenüber Fleisch- und Wurstkonsum und kann zum Umkippen bisheriger Konsummuster führen (Tipping-Point). Für EDEKA Südwestfleisch und Schwarzwaldhof erfordert dies – aufbauend auf der bisherigen Ausrichtung an Nachhaltigkeit – eine zukunftsorientierte Planung des Sortiments im veganen, vegetarischen, hybriden Sektor und im Bereich Bio-Produkte und Tierwohl. Hierfür muss auch die Kommunikationspolitik angepasst werden, um jüngere Zielgruppen zu erreichen, damit das Dilemma der Fleischwirtschaft (Tierwohl wird gefordert, aber nicht in gleichem Masse gekauft) nicht zu Lasten des Markterfolgs geht.
Vorgestellt wird ein Konzept zur biologischen Methanisierung von Wasserstoff direkt in Biogasreaktoren, mit dem durch Membranbegasung der Methangehalt des Biogases auf > 96 % erhöht werden kann. Essentiell zum Erreichen solch hoher Methanwerte sind die Einhaltung eines optimalen pH-Bereichs und die Vermeidung von H2-Akkumulation. Im Falle einer Limitierung der Methanbildungsrate durch den eigentlichen anaeroben Abbauprozess der Biomasse ist auch eine externe Zufuhr von CO2 zur weiteren Methanbildung denkbar. Das Verfahren soll weiter optimiert und in einem von der Deutschen Bundesstiftung Umwelt geförderten Projekt in der Biogasanlage einer regionalen Käserei in der Praxis getestet werden. Die hier angestrebte Kombination aus dezentraler Abfallverwertung und Eigenenergieerzeugung eines lebensmittelverarbeitenden Betriebs unter Einbindung in ein intelligentes Erneuerbare Energien - Konzept soll einen zusätzlichen Mehrwert liefern.
Biomechanical Risk Factors of Injury-Related Single-Leg Movements in Male Elite Youth Soccer Players
(2022)
Altered movement patterns during single-leg movements in soccer increase the risk of lower-extremity non-contact injuries. The identification of biomechanical parameters associated with lower-extremity injuries can enrich knowledge of injury risks and facilitate injury prevention. Fifty-six elite youth soccer players performed a single-leg drop landing task and an unanticipated side-step cutting task. Three-dimensional ankle, knee and hip kinematic and kinetic data were obtained, and non-contact lower-extremity injuries were documented throughout the season. Risk profiling was assessed using a multivariate approach utilising a decision tree model (classification and regression tree method). The decision tree model indicated peak knee frontal plane angle, peak vertical ground reaction force, ankle frontal plane moment and knee transverse plane angle at initial contact (in this hierarchical order) for the single-leg landing task as important biomechanical parameters to discriminate between injured and non-injured players. Hip sagittal plane angle at initial contact, peak ankle transverse plane angle and hip sagittal plane moment (in this hierarchical order) were indicated as risk factors for the unanticipated cutting task. Ankle, knee and hip kinematics, as well as ankle and hip kinetics, during single-leg high-risk movements can provide a good indication of injury risk in elite youth soccer players.
BioPower
(2009)
Das Projekt BioPower ist eine Kooperation des Instituts für Angewandte Forschung (IAF) der Hochschule Offenburg mit dem Institut für Mikrosystemtechnik (IMTEK) der Universität Freiburg. Es handelt sich um den Versuch, die im Körper vorhandenen Energiequellen sozusagen direkt anzuzapfen, um sie für technische Zwecke zu nutzen. Von den vielen bestehenden Möglichkeiten konzentriert sich die Forschung hier auf die Nutzung der Glukose im Blut, die auch sonst als Energieträger zur Versorgung der Zellen im Körper dient.
Informatik-Veranstaltungen in der Fakultät Medien und Informationswesen vermitteln meist komplexe Inhalte, die anschließend in begleitenden Laborveranstaltungen praktisch und an konkretenBeispielen vertieft werden. Allerdings benötigen die Studierenden für ein lehrreiches Labor und die selbstständige Erarbeitung korrekter Lösungen einige Grundkenntnisse, die aus der jeweiligen Theorieveranstaltung mitgebracht werden müssen.<br> Um den Studierenden weiterhin die Möglichkeiten zu geben, den Stoff der Lehrveranstaltungen raum- und zeitunabhängig nachzuarbeiten und auch didaktisch aufbereitete Übungen virtuell durchzuführen, haben wir zu den Veranstaltungen Software Engineering, Computernetze und Datenbanken webbasierte E-Learning-Materialien konzipiert und erstellt. Diese Lernarrangements bieten den Lernenden die Möglichkeit, selbstbestimmt im eigenen Lernrhythmus und über unterschiedliche Medien einen Zugang zu der Thematik zu finden. Hybride Lernarrangements (Blended Learning) versuchen hier die Vorteile unterschiedlicher didaktischer Methoden und Medien miteinander zu kombinieren [1].