Refine
Year of publication
- 2021 (154) (remove)
Institute
- Fachbereich Medizintechnik und Technomathematik (53)
- IfB - Institut für Bioengineering (35)
- Fachbereich Elektrotechnik und Informationstechnik (25)
- Fachbereich Luft- und Raumfahrttechnik (23)
- Fachbereich Energietechnik (17)
- INB - Institut für Nano- und Biotechnologien (15)
- Fachbereich Chemie und Biotechnologie (11)
- Fachbereich Bauingenieurwesen (10)
- Solar-Institut Jülich (10)
- ECSM European Center for Sustainable Mobility (9)
Language
- English (154) (remove)
Document Type
- Article (86)
- Conference Proceeding (48)
- Part of a Book (12)
- Book (2)
- Doctoral Thesis (2)
- Conference: Meeting Abstract (1)
- Other (1)
- Preprint (1)
- Working Paper (1)
Keywords
- Hydrogen (2)
- NOx emissions (2)
- Out-of-plane load (2)
- PCM (2)
- Principal component analysis (2)
- autonomous driving (2)
- building information modelling (2)
- capacitive field-effect sensor (2)
- constructive alignment (2)
- earthquakes (2)
- electro mobility (2)
- examination (2)
- harmonic radar (2)
- hydrogen (2)
- industrial facilities (2)
- installations (2)
- long-term retention (2)
- management (2)
- multimodal (2)
- piping (2)
- practical learning (2)
- robotic process automation (2)
- seismic loading (2)
- 3D object detection (1)
- 3D printing (1)
- 3D-printing (1)
- Adaptive Systems (1)
- Aircraft sizing (1)
- AlterG (1)
- Augmented Reality (1)
- Authenticity (1)
- BIM (1)
- Bacillus sp (1)
- Biosolubilization (1)
- Bloom’s Taxonomy (1)
- Bone quality and biomechanics (1)
- Bootstrap (1)
- Boundary integral equations (1)
- CFD (1)
- Capacitive field-effect sensor (1)
- CellDrum (1)
- Central receiver power plant (1)
- Coefficient of ocular rigidity (1)
- Competence Developing Games (1)
- Computational modeling (1)
- Concentrated systems (1)
- Concentrating solar power (1)
- Corneo-scleral shell (1)
- Cross-platform (1)
- DLR-ESTEC GOSSAMER roadmap for solar sailing (1)
- Deep learning (1)
- Deuterated solvents (1)
- Deuterium NMR (1)
- Differential tonometry (1)
- Drinfeld modules (1)
- EEG (1)
- ESATAN (1)
- Earthquake (1)
- Earthquake Engineering (1)
- Emissions (1)
- Empirical process (1)
- Enterprise Architecture (1)
- Environmental impact (1)
- Error Recovery (1)
- Evaluation (1)
- Eyeball (1)
- Flame residence time (1)
- Flame temperature (1)
- Frame structure (1)
- Frequency Doubler (1)
- Frequency mixing magnetic detection (1)
- Freshmen (1)
- Fresnel power plant (1)
- Fuel-flexibility (1)
- Functional Delta Method (1)
- GEO (1)
- GOSSAMER-1 (1)
- GPU (1)
- Game-based learning (1)
- Gamification (1)
- Gas turbine (1)
- Gas turbine combustion (1)
- Glaucoma (1)
- HVAC (1)
- Hadamard differentiability (1)
- Harmonic Radar (1)
- Helmholtz equation (1)
- Heparin (1)
- Heuristic algorithms (1)
- Hilbert Room (1)
- Hyperdifferentials (1)
- IR (1)
- IR spectroscopy (1)
- IT security education (1)
- ITS (1)
- Impedance Spectroscopy (1)
- Implementation Case (1)
- In- plane damage (1)
- Infused Thermal Solutions (1)
- Interior Neumann eigenvalues (1)
- Keyword analysis (1)
- LEO (1)
- LPS (1)
- Label-free detection (1)
- Langevin theory (1)
- LiDAR (1)
- Lightning protection system (1)
- Linear discriminant analysis (1)
- MUT measurement; scanner (1)
- Machine learning (1)
- Magnetic nanoparticles (1)
- Manufacturer (1)
- Masonry infill (1)
- Micromagnetic simulation (1)
- Micromix (1)
- Mixed-integer nonlinear programming (1)
- Mobile web (1)
- Modelica (1)
- Multi-storey (1)
- Muscle Fascicle (1)
- Muscle Force (1)
- NOx (1)
- Natural language processing (1)
- Nonequilibrium dynamics (1)
- Numerics (1)
- Ocular blood flow (1)
- Operators (1)
- Optimization (1)
- Out-of-plane failure (1)
- Out-of-plane strength (1)
- PWA (1)
- Paired sample (1)
- Parasitic drag (1)
- Piping (1)
- Plant virus (1)
- Postulates (1)
- Potential theory (1)
- Powertrain (1)
- Pressure-volume relationship (1)
- Process model (1)
- Progressive Web App (1)
- Quantenmechanik (1)
- RVA (1)
- Radar (1)
- Rescue System (1)
- Resilience (1)
- Robotic Process Automation (1)
- Robotic process automation (1)
- SFCW (1)
- Schrödingers cat (1)
- Seismic loading (1)
- Septic cardiomyopathy (1)
- Sharing mobility (1)
- Simulation (1)
- Skeletal muscle (1)
- Sleep EEG (1)
- Small Aral Sea (1)
- Small spacecraft (1)
- Smart Building Engineering (1)
- Soft independent modeling of class analogy (1)
- Solar sail (1)
- Standardization (1)
- Stiffness (1)
- TMV adsorption (1)
- Tag (1)
- Tank (1)
- Ta₂O₅ gate (1)
- Tendon Rupture (1)
- Tendons (1)
- Three-dimensional displays (1)
- Tobacco mosaic virus (TMV) (1)
- Transcendence (1)
- Transponder (1)
- UAV (1)
- Ultrasound (1)
- Unreinforced masonry walls (1)
- VOP compression (1)
- Validation (1)
- Vascular response (1)
- Visual field asymmetry (1)
- Water distribution system (1)
- Zeta potential (1)
- acetoin (1)
- acetoin reductase (1)
- actin cytoskeleton (1)
- actuator-sensor system (1)
- additive manufactureing (1)
- alcoholic beverages (1)
- applications (1)
- artificial intelligence (1)
- autonomous navigation (1)
- bioburdens (1)
- biopotential electrodes (1)
- biosensors (1)
- body imaging at UHF MRI (1)
- building energy modelling (1)
- building energy simulation (1)
- business culture (1)
- business models (1)
- business process automation (1)
- capacitive EIS sensor (1)
- capacitive electrolyte–insulator–semiconductor sensors (1)
- capacitive field-effect sensors (1)
- cardiomyocyte biomechanics (1)
- change (1)
- colorization (1)
- combustor (1)
- combustor development (1)
- commercial offthe- shelf solutions (1)
- construction (1)
- control gate (1)
- crop yield (1)
- culpability (1)
- cyber physical production system (1)
- cyber-physical production systems (1)
- detection of charged macromolecules (1)
- digital factory (1)
- digital shadow (1)
- digitalization (1)
- dissemination (1)
- do-it-yourself (1)
- down-conductor (1)
- drop jump (1)
- early warning and response system (1)
- ecological structure (1)
- education (1)
- electrically driven compressors (1)
- embedded hardware (1)
- emote practical training (1)
- energy transition (1)
- engine demonstration (1)
- enzymatic biosensor (1)
- enzyme kinetics (1)
- equivalent circuit (1)
- event-based simulation (1)
- field-effect sensor (1)
- food production (1)
- fragility curves (1)
- frequency mixing magnetic detection (1)
- fuel cell (1)
- fuels (1)
- gait (1)
- gas turbine (1)
- genetic algorithm (1)
- glass (1)
- global optimization (1)
- gold nanoparticles (1)
- graphene oxide (1)
- harmonic radar tags (1)
- heat demand (1)
- heat transfer coefficient (1)
- humic acid (1)
- hyper-gravity (1)
- hypo-gravity (1)
- industrial agents (1)
- industrial gas turbine (1)
- information systems (1)
- integrated transmit coil arrays (1)
- integration SHM in BIM (1)
- interconnected sensor systems (1)
- internal combustion engine (1)
- internet of production (1)
- intraclass correlation coefficient (1)
- large-scale inspection (1)
- laser based powder fusion (1)
- latent heat (1)
- lattice (1)
- layer-by-layer technique (1)
- liability (1)
- light-addressable electrode (1)
- light-addressable potentiometric sensor (1)
- lignite (1)
- lockdown conditions (1)
- locomotion (1)
- low-rank coal (1)
- magnetic nanoparticles (1)
- masonry structures (1)
- metagenomics (1)
- metal façade (1)
- microbial diversity (1)
- microfluidics (1)
- microwave measurements (1)
- mobile manipulation (1)
- mobility behaviour (1)
- model-predictive control (1)
- motivation (1)
- multi-agent systems (1)
- multianalyte detection (1)
- multiplex detection (1)
- muscle fascicle behavior (1)
- muscle mechanics (1)
- nanomaterials (1)
- nonlinear VNA measurements (1)
- nonlinear radar (1)
- on-chip integrated addressable EISCAP sensors (1)
- open educational resources (1)
- parabolic flight (1)
- passive thermal control (1)
- penicillin (1)
- penicillinase (1)
- photoelectrochemistry (1)
- plant virus detection (1)
- polyaniline (1)
- polystyrene sulfonate (1)
- prefabrication (1)
- qNMR (1)
- rehabilitation (1)
- remote teamwork (1)
- renewable energies (1)
- research framework (1)
- roleplay (1)
- running (1)
- sarcomere operating length (1)
- seismic risk (1)
- seismic structural damage detection via SHM (1)
- seismic vulnerability (1)
- sensor networks (1)
- sensors (1)
- series elastic element behavior (1)
- shotgun sequencing (1)
- shoulder (1)
- small and medium scaled companies (1)
- smart building engineering (1)
- smart engineering (1)
- software evaluation (1)
- software selection (1)
- soil amendment (1)
- soil health (1)
- soil remediation (1)
- sprint start (1)
- standard error of measurement (1)
- star tracker (1)
- steel columns (1)
- sterility tests (1)
- sterilization efficacy (1)
- sterilization methods (1)
- stochastic optimization (1)
- storage dispatch (1)
- storage optimisation (1)
- stretch reflex (1)
- subroutine (1)
- surface-orthogonal path planning (1)
- sustainability (1)
- t-modules (1)
- technology (1)
- test-retest reliability (1)
- thermal storage (1)
- thermo-physical (1)
- titanium dioxide photoanode (1)
- tobacco mosaic virus (TMV) (1)
- touch voltage (1)
- transponder (1)
- ultrasonography (1)
- ultrasound imaging (1)
- unloading (1)
- urban farming (1)
- user & usage (1)
- validation methods (1)
- virtual reality (1)
- walking (1)
- wind turbine production (1)
For typical cases of non-isolated lightning protection systems (LPS) the impulse currents are investigated which may flow through a human body directly touching a structural part of the LPS. Based on a basic LPS model with conventional down-conductors especially the cases of external and internal steel columns and metal façades are considered and compared. Numerical simulations of the line quantities voltages and currents in the time domain are performed with an equivalent circuit of the entire LPS.
As a result it can be stated that by increasing the number of conventional down-conductors and external steel columns the threat for a human being can indeed be reduced, but not down to an acceptable limit. In case of internal steel columns used as natural down-conductors the threat can be reduced sufficiently, depending on the low-resistive connection of the steel columns to the lightning equipotential bonding or the earth termination system, resp. If a metal façade is used the threat for human beings touching is usually very low, if the façade is sufficiently interconnected and multiply connected to the lightning equipotential bonding or the earth termination system, resp.
Modern industry and multi-discipline projects require highly trained individuals with resilient science and engineering back-grounds. Graduates must be able to agilely apply excellent theoretical knowledge in their subject matter as well as essential practical “hands-on” knowledge of diverse working processes to solve complex problems. To meet these demands, university education follows the concept of Constructive Alignment and thus increasingly adopts the teaching of necessary practical skills to the actual industry requirements and assessment routines. However, a systematic approach to coherently align these three central teaching demands is strangely absent from current university curricula. We demonstrate the feasibility of implementing practical assessments in a regular theory-based examination, thus defining the term “blended assessment”. We assessed a course for natural science and engineering students pursuing a career in biomedical engineering, and evaluated the benefit of blended assessment exams for students and lecturers. Our controlled study assessed the physiological background of electrocardiograms (ECGs), the practical measurement of ECG curves, and their interpretation of basic pathologic alterations. To study on long time effects, students have been assessed on the topic twice with a time lag of 6 months. Our findings suggest a significant improvement in student gain with respect to practical skills and theoretical knowledge. The results of the reassessments support these outcomes. From the lecturers ́ point of view, blended assessment complements practical training courses while keeping organizational effort manageable. We consider blended assessment a viable tool for providing an improved student gain, industry-ready education format that should be evaluated and established further to prepare university graduates optimally for their future careers.
Delayed cerebral ischemia (DCI) is a common complication after aneurysmal subarachnoid hemorrhage (aSAH) and can lead to infarction and poor clinical outcome. The underlying mechanisms are still incompletely understood, but animal models indicate that vasoactive metabolites and inflammatory cytokines produced within the subarachnoid space may progressively impair and partially invert neurovascular coupling (NVC) in the brain. Because cerebral and retinal microvasculature are governed by comparable regulatory mechanisms and may be connected by perivascular pathways, retinal vascular changes are increasingly recognized as a potential surrogate for altered NVC in the brain. Here, we used non-invasive retinal vessel analysis (RVA) to assess microvascular function in aSAH patients at different times after the ictus.
Purpose Vascular risk factors and ocular perfusion are heatedly discussed in the pathogenesis of glaucoma. The retinal vessel analyzer (RVA, IMEDOS Systems, Germany) allows noninvasive measurement of retinal vessel regulation. Significant differences especially in the veins between healthy subjects and patients suffering from glaucoma were previously reported. In this pilot-study we investigated if localized vascular regulation is altered in glaucoma patients with altitudinal visual field defect asymmetry. Methods 15 eyes of 12 glaucoma patients with advanced altitudinal visual field defect asymmetry were included. The mean defect was calculated for each hemisphere separately (-20.99 ± 10.49 pro- found hemispheric visual field defect vs -7.36 ± 3.97 dB less profound hemisphere). After pupil dilation, RVA measurements of retinal arteries and veins were conducted using the standard protocol. The superior and inferior retinal vessel reactivity were measured consecutively in each eye. Results Significant differences were recorded in venous vessel constriction after flicker light stimulation and overall amplitude of the reaction (p \ 0.04 and p \ 0.02 respectively) in-between the hemispheres spheres. Vessel reaction was higher in the hemisphere corresponding to the more advanced visual field defect. Arterial diameters reacted similarly, failing to reach statistical significance. Conclusion Localized retinal vessel regulation is significantly altered in glaucoma patients with asymmetri altitudinal visual field defects. Veins supplying the hemisphere concordant to a less profound visual field defect show diminished diameter changes. Vascular dysregulation might be particularly important in early glaucoma stages prior to a significant visual field defect.
The term ocular rigidity is widely used in clinical ophthalmology. Generally it is assumed as a resistance of the whole eyeball to mechanical deformation and relates to biomechanical properties of the eye and its tissues. Basic principles and formulas for clinical tonometry, tonography and pulsatile ocular blood flow measurements are based on the concept of ocular rigidity. There is evidence for altered ocular rigidity in aging, in several eye diseases and after eye surgery. Unfortunately, there is no consensual view on ocular rigidity: it used to make a quite different sense for different people but still the same name. Foremost there is no clear consent between biomechanical engineers and ophthalmologists on the concept. Moreover ocular rigidity is occasionally characterized using various parameters with their different physical dimensions. In contrast to engineering approach, clinical approach to ocular rigidity claims to characterize the total mechanical response of the eyeball to its deformation without any detailed considerations on eye morphology or material properties of its tissues. Further to the previous chapter this section aims to describe clinical approach to ocular rigidity from the perspective of an engineer in an attempt to straighten out this concept, to show its advantages, disadvantages and various applications.
The transition within transportation towards battery electric vehicles can lead to a more sustainable future. To account for the development goal ‘climate action’ stated by the United Nations, it is mandatory, within the conceptual design phase, to derive energy-efficient system designs. One barrier is the uncertainty of the driving behaviour within the usage phase. This uncertainty is often addressed by using a stochastic synthesis process to derive representative driving cycles and by using cycle-based optimization. To deal with this uncertainty, a new approach based on a stochastic optimization program is presented. This leads to an optimization model that is solved with an exact solver. It is compared to a system design approach based on driving cycles and a genetic algorithm solver. Both approaches are applied to find efficient electric powertrains with fixed-speed and multi-speed transmissions. Hence, the similarities, differences and respective advantages of each optimization procedure are discussed.
The course Physics for Electrical Engineering is part of the curriculum of the bachelor program Electrical Engineering at University of Applied Science Aachen.
Before covid-19 the course was conducted in a rather traditional way with all parts (lecture, exercise and lab) face-to-face. This teaching approach changed fundamentally within a week when the covid-19 limitations forced all courses to distance learning. All parts of the course were transformed to pure distance learning including synchronous and asynchronous parts for the lecture, live online-sessions for the exercises and self-paced labs at home. Using these methods, the course was able to impart the required knowledge and competencies. Taking the teacher’s observations of the student’s learning behaviour and engagement, the formal and informal feedback of the students and the results of the exams into account, the new methods are evaluated with respect to effectiveness, sustainability and suitability for competence transfer. Based on this analysis strong and weak points of the concept and countermeasures to solve the weak points were identified. The analysis further leads to a sustainable teaching approach combining synchronous and asynchronous parts with self-paced learning times that can be used in a very flexible manner for different learning scenarios, pure online, hybrid (mixture of online and presence times) and pure presence teaching.
Adapting augmented reality systems to the users’ needs using gamification and error solving methods
(2021)
Animations of virtual items in AR support systems are typically predefined and lack interactions with dynamic physical environments. AR applications rarely consider users’ preferences and do not provide customized spontaneous support under unknown situations. This research focuses on developing adaptive, error-tolerant AR systems based on directed acyclic graphs and error resolving strategies. Using this approach, users will have more freedom of choice during AR supported work, which leads to more efficient workflows. Error correction methods based on CAD models and predefined process data create individual support possibilities. The framework is implemented in the Industry 4.0 model factory at FH Aachen.
Component failures within water supply systems can lead to significant performance losses. One way to address these losses is the explicit anticipation of failures within the design process. We consider a water supply system for high-rise buildings, where pump failures are the most likely failure scenarios. We explicitly consider these failures within an early design stage which leads to a more resilient system, i.e., a system which is able to operate under a predefined number of arbitrary pump failures. We use a mathematical optimization approach to compute such a resilient design. This is based on a multi-stage model for topology optimization, which can be described by a system of nonlinear inequalities and integrality constraints. Such a model has to be both computationally tractable and to represent the real-world system accurately. We therefore validate the algorithmic solutions using experiments on a scaled test rig for high-rise buildings. The test rig allows for an arbitrary connection of pumps to reproduce scaled versions of booster station designs for high-rise buildings. We experimentally verify the applicability of the presented optimization model and that the proposed resilience properties are also fulfilled in real systems.
This chapter describes three general strategies to master uncertainty in technical systems: robustness, flexibility and resilience. It builds on the previous chapters about methods to analyse and identify uncertainty and may rely on the availability of technologies for particular systems, such as active components. Robustness aims for the design of technical systems that are insensitive to anticipated uncertainties. Flexibility increases the ability of a system to work under different situations. Resilience extends this characteristic by requiring a given minimal functional performance, even after disturbances or failure of system components, and it may incorporate recovery. The three strategies are described and discussed in turn. Moreover, they are demonstrated on specific technical systems.
Geochemical characterisation of hypersaline waters is difficult as high concentrations of salts hinder the analysis of constituents at low concentrations, such as trace metals, and the collection of samples for trace metal analysis in natural waters can be easily contaminated. This is particularly the case if samples are collected by non-conventional techniques such as those required for aquatic subglacial environments. In this paper we present the first analysis of a subglacial brine from Taylor Valley, (~ 78°S), Antarctica for the trace metals: Ba, Co, Mo, Rb, Sr, V, and U. Samples were collected englacially using an electrothermal melting probe called the IceMole. This probe uses differential heating of a copper head as well as the probe’s sidewalls and an ice screw at the melting head to move through glacier ice. Detailed blanks, meltwater, and subglacial brine samples were collected to evaluate the impact of the IceMole and the borehole pump, the melting and collection process, filtration, and storage on the geochemistry of the samples collected by this device. Comparisons between melt water profiles through the glacier ice and blank analysis, with published studies on ice geochemistry, suggest the potential for minor contributions of some species Rb, As, Co, Mn, Ni, NH4+, and NO2−+NO3− from the IceMole. The ability to conduct detailed chemical analyses of subglacial fluids collected with melting probes is critical for the future exploration of the hundreds of deep subglacial lakes in Antarctica.
Concentrating Solar Power
(2021)
The focus of this chapter is the production of power and the use of the heat produced from concentrated solar thermal power (CSP) systems.
The chapter starts with the general theoretical principles of concentrating systems including the description of the concentration ratio, the energy and mass balance. The power conversion systems is the main part where solar-only operation and the increase in operational hours.
Solar-only operation include the use of steam turbines, gas turbines, organic Rankine cycles and solar dishes. The operational hours can be increased with hybridization and with storage.
Another important topic is the cogeneration where solar cooling, desalination and of heat usage is described.
Many examples of commercial CSP power plants as well as research facilities from the past as well as current installed and in operation are described in detail.
The chapter closes with economic and environmental aspects and with the future potential of the development of CSP around the world.
Test-retest reliability of the internal shoulder rotator muscles' stretch reflex in healthy men
(2021)
Until now the reproducibility of the short latency stretch reflex of the internal rotator muscles of the glenohumeral joint has not been identified. Twenty-three healthy male participants performed three sets of external shoulder rotation stretches with various pre-activation levels on two different dates of measurement to assess test-retest reliability. All stretches were applied with a dynamometer acceleration of 104°/s2 and a velocity of 150°/s. Electromyographical response was measured via surface EMG. Reflex latencies showed a pre-activation effect (ƞ2 = 0,355). ICC ranged from 0,735 to 0,909 indicating an overall “good” relative reliability. SRD 95% lay between ±7,0 to ±12,3 ms.. The reflex gain showed overall poor test-retest reproducibility. The chosen methodological approach presented a suitable test protocol for shoulder muscles stretch reflex latency evaluation. A proof-of-concept study to validate the presented methodical approach in shoulder involvement including subjects with clinically relevant conditions is recommended.
One central challenge for self-driving cars is a proper path-planning. Once a trajectory has been found, the next challenge is to accurately and safely follow the precalculated path. The model-predictive controller (MPC) is a common approach for the lateral control of autonomous vehicles. The MPC uses a vehicle dynamics model to predict the future states of the vehicle for a given prediction horizon. However, in order to achieve real-time path control, the computational load is usually large, which leads to short prediction horizons. To deal with the computational load, the control algorithm can be parallelized on the graphics processing unit (GPU). In contrast to the widely used stochastic methods, in this paper we propose a deterministic approach based on grid search. Our approach focuses on systematically discovering the search area with different levels of granularity. To achieve this, we split the optimization algorithm into multiple iterations. The best sequence of each iteration is then used as an initial solution to the next iteration. The granularity increases, resulting in smooth and predictable steering angle sequences. We present a novel GPU-based algorithm and show its accuracy and realtime abilities with a number of real-world experiments.
Microbial diversity studies regarding the aquatic communities that experienced or are experiencing environmental problems are essential for the comprehension of the remediation dynamics. In this pilot study, we present data on the phylogenetic and ecological structure of microorganisms from epipelagic water samples collected in the Small Aral Sea (SAS). The raw data were generated by massive parallel sequencing using the shotgun approach. As expected, most of the identified DNA sequences belonged to Terrabacteria and Actinobacteria (40% and 37% of the total reads, respectively). The occurrence of Deinococcus-Thermus, Armatimonadetes, Chloroflexi in the epipelagic SAS waters was less anticipated. Surprising was also the detection of sequences, which are characteristic for strict anaerobes—Ignavibacteria, hydrogen-oxidizing bacteria, and archaeal methanogenic species. We suppose that the observed very broad range of phylogenetic and ecological features displayed by the SAS reads demonstrates a more intensive mixing of water masses originating from diverse ecological niches of the Aral-Syr Darya River basin than presumed before.