Article
Refine
Year of publication
Institute
- Fachbereich Medizintechnik und Technomathematik (1358)
- INB - Institut für Nano- und Biotechnologien (503)
- Fachbereich Chemie und Biotechnologie (472)
- Fachbereich Elektrotechnik und Informationstechnik (414)
- IfB - Institut für Bioengineering (411)
- Fachbereich Energietechnik (361)
- Fachbereich Luft- und Raumfahrttechnik (254)
- Fachbereich Maschinenbau und Mechatronik (148)
- Fachbereich Wirtschaftswissenschaften (116)
- Fachbereich Bauingenieurwesen (69)
Language
- English (3277) (remove)
Document Type
- Article (3277) (remove)
Keywords
- Einspielen <Werkstoff> (7)
- avalanche (5)
- Earthquake (4)
- FEM (4)
- Finite-Elemente-Methode (4)
- LAPS (4)
- biosensors (4)
- field-effect sensor (4)
- frequency mixing magnetic detection (4)
- CellDrum (3)
- Heparin (3)
- Label-free detection (3)
- additive manufacturing (3)
- capacitive field-effect sensor (3)
- hydrogen peroxide (3)
- impedance spectroscopy (3)
- magnetic nanoparticles (3)
- shakedown analysis (3)
- snow (3)
- sustainability (3)
- tobacco mosaic virus (TMV) (3)
- Acyl-amino acids (2)
- Aeroelasticity (2)
- Aminoacylase (2)
- Bacillaceae (2)
- Bacillus atrophaeus (2)
- Biotechnological application (2)
- Boundary integral equations (2)
- Brake set-up (2)
- Butanol (2)
- CFD (2)
- Capacitive field-effect sensor (2)
- Chemometrics (2)
- Conductive boundary condition (2)
- Drinfeld modules (2)
- Einspielanalyse (2)
- Empirical process (2)
- Fault detection (2)
- Field-effect sensor (2)
- Freight rail (2)
- Germany (2)
- Goodness-of-fit test (2)
- Hot S-parameter (2)
- IR spectroscopy (2)
- Independence test (2)
- Light-addressable potentiometric sensor (2)
- Lipopolysaccharide (2)
- MINLP (2)
- Methane (2)
- NMR spectroscopy (2)
- Obstacle avoidance (2)
- Paired sample (2)
- Parametric bootstrap (2)
- Path planning (2)
- Principal component analysis (2)
- Pump System (2)
- Raman spectroscopy (2)
- SLM (2)
- Shakedown analysis (2)
- Simulation (2)
- Standardization (2)
- Stiffness (2)
- Subtilases (2)
- Subtilisin (2)
- Traglastanalyse (2)
- Transcendence (2)
- Transmission eigenvalues (2)
- UAV (2)
- bacterial cellulose (2)
- bubble column (2)
- capacitive field-effect sensors (2)
- carbonized rice husk (2)
- constructive alignment (2)
- damage (2)
- energy efficiency (2)
- examination (2)
- factory planning (2)
- fused filament fabrication (2)
- gold nanoparticles (2)
- harmonic radar (2)
- immobilization (2)
- light-addressable potentiometric sensor (2)
- likelihood ratio test (2)
- limit analysis (2)
- locomotion (2)
- long-term retention (2)
- manufacturing flexibility (2)
- methanation (2)
- microfluidics (2)
- multimodal (2)
- muscle fascicle behavior (2)
- not identically distributed (2)
- penicillinase (2)
- plug flow reactor (2)
- practical learning (2)
- prebiotic (2)
- qNMR (2)
- rapid tooling (2)
- rebound-effect (2)
- shakedown (2)
- t-modules (2)
- ultrasound (2)
- ultrasound imaging (2)
- (Bio)degradation (1)
- (Poly)saccharides (1)
- 197m/gHg (1)
- 1P hub loads (1)
- 3-D printing (1)
- 316L (1)
- 3D nonlinear finite element model (1)
- 802.15.4 (1)
- ABE (1)
- Acceleration (1)
- Achilles tendon (1)
- Acid crash (1)
- Active humidity control (1)
- Actuator disk modelling (1)
- Acylation (1)
- Adaptive control (1)
- Additive Manufacturing (1)
- Additive manufacturing (1)
- Afterload (1)
- Ageing (1)
- Air purification (1)
- Aircraft sizing (1)
- Algal Turf Scrubber (1)
- Algal–bacterial bioflm (1)
- Alginate beads (1)
- Alkalihalobacillus okhensis (1)
- Aloe vera (1)
- AlterG (1)
- Alternating plasticity (1)
- Alzheimer's disease (1)
- Analysis (1)
- Analytischer Zulaessigkeitsnachweis (1)
- Anammox (1)
- Anastomotic leakage (1)
- Anatomy (1)
- Annulus Fibrosus (1)
- Antarctic Glaciology (1)
- Antibias (1)
- Architectural design (1)
- Architectural gear ratio (1)
- Artificial intelligence (1)
- Assembly (1)
- Assistive technology (1)
- Asymptotic efficiency (1)
- Authenticity (1)
- Autolysis (1)
- Automated driving (1)
- Automatic control (1)
- Automotive application (1)
- Automotive safety approach (1)
- Autonomy (1)
- Avalanche (1)
- Axialbelastung (1)
- Axially cracked pipe (1)
- BET (1)
- Bacillus atrophaeus spores (1)
- Bacillus sp (1)
- Bacterial cellulose (1)
- Balance (1)
- Balanced hypergraph (1)
- Bank-issued Warrants (1)
- Basis Reduktion (1)
- Basis reduction (1)
- Bauingenieurwesen (1)
- Behaviour factor q (1)
- Benchmark (1)
- Bicharakteristikenverfahren (1)
- Bio-inspired systems (1)
- Bioabsorbable (1)
- Biocatalysis (1)
- Biocomposites (1)
- Biofuel (1)
- Biogas (1)
- Biological hydrogen (1)
- Biomass (1)
- Biomechanical simulation (1)
- Bioreaktor (1)
- Biorefinery (1)
- Biosolubilization (1)
- Biosurfactants (1)
- Blade element method (1)
- Bloom’s Taxonomy (1)
- Bluetooth (1)
- Blutzellenlagerung (1)
- Bone quality and biomechanics (1)
- Booster Station (1)
- Booster Stations (1)
- Bootstrap (1)
- Bootstrapping (1)
- Borehole heat exchanger (1)
- Boundary integral equations, (1)
- Bragg peak (1)
- Brake test (1)
- Braking curves (1)
- Brands (1)
- Broad pH spectrum (1)
- Brownian Pillow (1)
- Buffering Capacity (1)
- C. acetobutylicum (1)
- CAD (1)
- CAV (1)
- CFD propeller simulation (1)
- CNOT (1)
- CO2 emission reduction targets (1)
- CRISPR/Cas9 (1)
- Calorimetric gas sensor (1)
- Capacitive field-effect (1)
- Capacitive model (1)
- Carbon sources (1)
- Cardiac myocytes (1)
- Cardiac tissue (1)
- Cardiovascular MRI (1)
- Cardiovascular Magnetic Resonance (1)
- Carrier solvents (1)
- Categorial variable (1)
- Cell permeability (1)
- Cellular force (1)
- Cellulose nanostructure (1)
- Cement infiltration (1)
- Cementoblast (1)
- Censored data (1)
- Centrifugal twisting moment (1)
- Chance Constraint (1)
- Change (1)
- Chaperone (1)
- Chaperone co-expression (1)
- Charging station (1)
- Chemical images (1)
- Chemical imaging sensor (1)
- Chemical sensor (1)
- Chondroitin sulfate (1)
- Circuit simulation (1)
- Circular Dichroism (1)
- Circular bioeconomy (1)
- Civil engineering (1)
- Clinical decision support systems (1)
- Clostridium acetobutylicum (1)
- Clusterion (1)
- Co-managed care (1)
- Coal (1)
- Collective risk model (1)
- Commercial Vehicle (1)
- Common Rail Injection System (1)
- Competence Developing Games (1)
- Competitiveness (1)
- Complex System (1)
- Complex-valued eigenvalues (1)
- Compliance (1)
- Compression (1)
- Computational biomechanics (1)
- Concomitant (1)
- Conductive Boundary Condition (1)
- Consensus (1)
- Conservation laws (1)
- Constitutive model (1)
- Contractile tension (1)
- Contractility (1)
- Convex optimization (1)
- Cost function (1)
- Cost-effectiveness (1)
- Coverage probability (1)
- Cramér-von-Mises statistic (1)
- Cramér-von-Mises test (1)
- Crashworthiness (1)
- Cross border adjustment mechanism (1)
- Crude heparin (1)
- Crámer–von-Mises distance (1)
- Culture media (1)
- Cyclotron production (1)
- C–V method (1)
- DAC (1)
- DLR-ESTEC GOSSAMER roadmap for solar sailing (1)
- DNA biosensor (1)
- DNA hybridization (1)
- DPA (dipicolinic acid) (1)
- Damage mechanics theory (1)
- Dark fermentation (1)
- Decomposition (1)
- Decoupling (1)
- Deformation (1)
- Dehydrogenase (1)
- Design-by-analysis (1)
- Detergent protease (1)
- Deuterated solvents (1)
- Deuterium NMR (1)
- Diaphorase (1)
- Diesel Engine (1)
- Dietary supplements (1)
- Dimensional splitting (1)
- Disc Degeneration (1)
- Discontinuous fractures (1)
- Discourse ethics (1)
- Discrete Optimization (1)
- Disposition Effect (1)
- Distributed Control Systems, (1)
- Diversity Management (1)
- Drag estimation (1)
- Driver assistance system (1)
- Driving cycle recognition (1)
- Druckbeanspruchung (1)
- Druckbehälter (1)
- Druckbelastung (1)
- Druckgeräte (1)
- Drug simulation (1)
- Dry-low-NOx (DLN) combustion (1)
- Duality (1)
- Dynamic simulation (1)
- E-Mobility (1)
- E. coli detection (1)
- ECMS (1)
- EGG (1)
- EIS capacitive sensor (1)
- ELISA (1)
- ES-FEM (1)
- Effective modal mass (1)
- Eigenvalue trajectories (1)
- Einspiel-Analyse (1)
- Einspiel-Kriterium (1)
- Einspielen (1)
- Elastizität (1)
- Elderly (1)
- Electrochemical impedance spectroscopy (1)
- Electrolyte–insulator–semiconductor (1)
- Electromagnetism (1)
- Electromechanical modeling (1)
- Electronic cigarettes (1)
- Electronic vehicle (1)
- Elemental (1)
- Emilia-Romagna earthquake (1)
- Empirical consequence curves (1)
- Empirical fragility functions (1)
- End-to-end colorectal anastomosis (1)
- Endothelial cells (1)
- Endothelial dysfunction (1)
- Energy management strategies (1)
- Energy-intensive industry (1)
- Engineering Application (1)
- Engineering Habitus (1)
- Enterprise information systems (1)
- Entropy solution (1)
- Environmental impact (1)
- Enzymatic biosensor (1)
- Enzyme coverage (1)
- Enzyme logic gate (1)
- Enzyme-linked immunosorbent assay (1)
- Epithel (1)
- Equivalence test (1)
- Esophageal Doppler monitor (1)
- European Transient Cycle (1)
- Eutectic Silver Copper alloy (1)
- Experiment (1)
- Experimental validation (1)
- Explainability (1)
- Exponential Euler scheme, (1)
- Exponential time differencing (1)
- Extension–twist coupling (1)
- External knee adduction moments (1)
- Extracellular enzymes (1)
- Extraterrestrial Glaciology (1)
- FS-FEM (1)
- Fall prevention (1)
- Fault approximation (1)
- Feature selection (1)
- Fehlerstellen (1)
- Fibroblast (1)
- Field effect (1)
- Field-effect biosensor (1)
- Finite difference methods (1)
- Finite differences (1)
- Finite element analysis (1)
- Finite element method (1)
- Finite element modelling (1)
- Finland (1)
- Fließgrenze (1)
- Floor prices (1)
- Flutter (1)
- Force (1)
- Forces (1)
- Fracture classification (1)
- Fracture configuration (1)
- Fracture simulation (1)
- Frame structure (1)
- Free-base nicotine (1)
- Freeze–thaw process (1)
- Frequency adaption (1)
- Frequency mixing magnetic detection (1)
- Fuel cell (1)
- Full-vehicle crash test (1)
- Functional Delta Method (1)
- Furnace (1)
- Fusion (1)
- GOSSAMER-1 (1)
- Ga-68 (1)
- Game-based learning (1)
- Gamification (1)
- Gamma distribution (1)
- Genetic algorithm (1)
- Geriatric (1)
- German (1)
- Glaciological instruments and methods (1)
- Glaucoma (1)
- Global and local collapse (1)
- Glucosamine (1)
- Gold nanoparticle (AuNP) (1)
- Gold nanoparticles (1)
- Goodness-of-fit tests for uniformity (1)
- Grenzwertberechnung (1)
- Ground-level falls (1)
- H2 (1)
- Hadamard differentiability (1)
- Haemodialysis (1)
- Hall’s Theorem (1)
- Halotolerant protease (1)
- Handbike (1)
- Harnleiter (1)
- Hazard assessment (1)
- Health management system (1)
- Heart tissue culture (1)
- Heat transport (1)
- Helmholtz equation (1)
- Hemoglobin structure (1)
- Heterostructure (1)
- High field MRI (1)
- High hydrogen combustion (1)
- High-field NMR (1)
- Higher derivations (1)
- Higher-order codes (1)
- Hip fractures (1)
- Hodgkin–Huxley models (1)
- Hoeffding-Blum-Kiefer-Rosenblatt independence test (1)
- Homogenization (1)
- Hotelling’s T² test (1)
- Human Development Index (1)
- Human factors (1)
- Human-Computer interaction (1)
- Hydrogen combustion (1)
- Hydrogen gas turbine (1)
- Hydrogen peroxide (1)
- Hydrogenotrophic methanogens (1)
- Hydrolysis (1)
- Hyperdifferentials (1)
- Hypergraph (1)
- Hypersecretion (1)
- Hämoglobin (1)
- Hämoglobinstruktur (1)
- INSYSME (1)
- IP-based networks (1)
- IR (1)
- IT security education (1)
- Illustration (1)
- Image Quality Assessment (1)
- Image Quality Score (1)
- Image Reconstruction (1)
- Imaging (1)
- Impedance analysis (1)
- Impedance spectroscopy (1)
- Implicit methods (1)
- In-plane performance, isolation (1)
- Incident analysis (1)
- Inclusion bodies (1)
- Incomplete data (1)
- Individual Investors (1)
- Induced pluripotent stem cells (1)
- Industrial Automation Technology, (1)
- Infill wall design (1)
- Information extraction (1)
- Inorganic ions (1)
- Inotropic compounds (1)
- Instructional design (1)
- Integrated empirical distribution (survival) function (1)
- Interior Neumann eigenvalues (1)
- Interior transmission eigenvalues (1)
- Interior transmission problem (1)
- Interstellar objects (1)
- Interval Time Series (1)
- Intervertebral Disc (1)
- Intradiscal Pressure (1)
- Inverse Scattering (1)
- Inverse dynamic problem (1)
- Inverse kinematic problem (1)
- Inverse scattering (1)
- Inverse scattering problem (1)
- Inverse spectral problem (1)
- Ion channels (1)
- Ions (1)
- Iterative learning control (1)
- Justice (1)
- Keyword analysis (1)
- Kinetic energy (1)
- Knochen (1)
- Knochenbildung (1)
- Knochenchirugie (1)
- Knochendichte (1)
- Koenig’s Theorem (1)
- Kohlenstofffaser (1)
- LPBF (1)
- LPS (1)
- Lab-on-Chip (1)
- Lactobacillus rhamnosus GG (1)
- Landslide tsunamis (1)
- Langevin theory (1)
- Large scale tests (1)
- Larynx position (1)
- Latvia (1)
- Layer-by-layer adsorption (1)
- LbL films (1)
- Left ventriular function (1)
- Level system (1)
- Li7La3Zr2O12 (1)
- LiGaO2 (1)
- Lidar (1)
- Lifting propeller (1)
- Light-addressable Potentiometric Sensor (1)
- Lignocellulose (1)
- Limit analysis (1)
- Linear discriminant analysis (1)
- Linear elastic analysis (1)
- Liver (1)
- Local path planning (1)
- Long COVID (1)
- Low field NMR (1)
- Low-field NMR (1)
- Luftreiniger (1)
- Luxury (1)
- MCDA (1)
- MILP (1)
- MOS (1)
- MR safety (1)
- MR-stethoscope (1)
- MRI (1)
- MST (1)
- MUT measurement; scanner (1)
- Machine learning (1)
- Magnetic field strength (1)
- Magnetic nanoparticles (1)
- Magnetic resonance imaging (MRI) (1)
- Magneto alert sensor (1)
- Mainstream (1)
- Manipulated variables (1)
- Manufacturer (1)
- Marginal homogeneity test (1)
- Marker-free mutagenesis (1)
- Masonry infill (1)
- Masonry partition walls (1)
- Master stamp (1)
- Matching (1)
- Materialermüdung (1)
- Matrix exponential (1)
- Measurement models (1)
- Measurement uncertainty (1)
- Mechanotransduction (1)
- Medical AI (1)
- Medical radionuclide production (1)
- Medusomyces gisevi (1)
- Meitner-Auger-electron (MAE) (1)
- Metabolic shift (1)
- Metal contaminants (1)
- Metascintillator (1)
- Methanogenesis (1)
- Microcirculation (1)
- Microfluidic solvent extraction (1)
- Micromagnetic simulation (1)
- Micromix combustion (1)
- Mikrosystemtechnik (1)
- Mild cognitive impairment (1)
- Missions (1)
- Mobility (1)
- Mobility tests (1)
- Mobility transition (1)
- Mode converter (1)
- Model-driven software engineering (1)
- Modelica (1)
- Modeling (1)
- Modelling (1)
- Modern constructions (1)
- Molecular modelling (1)
- Molecular weight determination (1)
- Molten salt receiver system (1)
- Molten salt solar tower (1)
- Monotone methods (1)
- Monte Carlo Tree Search (1)
- Morphing (1)
- Multi-criteria decision analysis (1)
- Multi-dimensional partial differential equations (1)
- Multi-objective optimization (1)
- Multi-sample problem (1)
- Multi-storey (1)
- Multianalyte detection (1)
- Multicell (1)
- Multiple TOF kernels (1)
- Multiplexing (1)
- Multirotor UAS (1)
- Muscle (1)
- Muscle Fascicle (1)
- Muscle Force (1)
- Musculoskeletal model (1)
- Musculoskeletal system (1)
- Myocardial infarction and cardiac death (1)
- NGN (1)
- NMR (1)
- NMR exchange relaxometry (1)
- NONOate (1)
- Natural fibres (1)
- Natural frequency (1)
- Negative Feedback Trading (1)
- Negative impedance convertor (1)
- Neural Network (1)
- Nitric Oxide (1)
- Nitric Oxide Donor (1)
- Nitrogen removal (1)
- Non-model-based Evaluation (1)
- Non-parallel fissures (1)
- Nonequilibrium dynamics (1)
- Nonlinear Dynamics (1)
- Nonlinear PDEs (1)
- Nonlinear eigenvalue problems (1)
- Normative standards (1)
- Nucleus Pulposus (1)
- Numerical inversion of Laplace transforms (1)
- Numerical linear algebra (1)
- Numerical modelling (1)
- Numerics (1)
- O2 plasma (1)
- Ocular blood flow (1)
- Online diagnostic (1)
- Operations (1)
- Organic acids (1)
- Organic light-emitting diode display (1)
- Organic waste (1)
- Organizational Culture (1)
- Organkultur (1)
- Osteoporose (1)
- Osteoporosis (1)
- Out-of-plane capacity (1)
- Overland flow (1)
- P2G (1)
- PBEE (1)
- PEM fuel cell (1)
- PIV (1)
- PLS-regression (1)
- PROFINET (1)
- Parabolic SPDEs (1)
- Paralympic sport (1)
- Parasitic drag (1)
- Parking (1)
- Partial nitritation (1)
- Penicillin (1)
- Periods (1)
- Permeability (1)
- Permeabilität (1)
- Peroxidase (1)
- Pflanzenphysiologie (1)
- Pflanzenscanner (1)
- Pflanzenstress (1)
- Pharmacology (1)
- Photolithographic mimics (1)
- Physiology (1)
- Piping (1)
- Plant virus (1)
- Plasma (1)
- Plasma diagnostics (1)
- Plasmacluster ion technology (1)
- Plastizität (1)
- Poly(allylamine hydrochloride) (1)
- Poly(d,l-lacticacid) (1)
- Polyimide (1)
- Polylactide acid (1)
- Polymer-matrix composites (1)
- Polysaccharides (1)
- Porositat (1)
- Post-COVID-19 syndrome (1)
- Potential theory (1)
- Powertrain (1)
- Pre-culture (1)
- Precast buildings (1)
- Predictive battery discharge (1)
- Preference assessment (1)
- Pressure loaded crack-face (1)
- Pretreatment (1)
- Prevention (1)
- Probability distribution mapping (1)
- Process virtualization (1)
- Product bundling (1)
- Product-integration (1)
- Progressive plastic deformation (1)
- Propeller (1)
- Propeller aerodynamics (1)
- Propeller elasticity (1)
- Propeller performance (1)
- Propeller whirl flutter (1)
- Proper Orthogonal Decomposition (1)
- Prophylaxis (1)
- Proximal humerus fracture (1)
- Pulsations (1)
- Pumping systems (1)
- Q-criterion (1)
- Quality control (1)
- Quantum chemistry (1)
- Quartz crystal microbalance (1)
- RAMMS (1)
- RVA (1)
- Radar (1)
- Rapid Prototyping (1)
- Rapid Technologie (1)
- Rapid prototyping (1)
- Ratchetting (1)
- Raumluft (1)
- Reaction-diffusion systems (1)
- Real distinct pole (1)
- Real-time monitoring (1)
- Recombinant activated protein C (1)
- Red blood cell storage (1)
- Regionalization (1)
- Rehabilitation Technology and Prosthetics (1)
- Rehabilitation engineering (1)
- Reinforced concrete frame (1)
- Relative air humidity (1)
- Requirements prioritization (1)
- Requirements relations (1)
- Resampling test (1)
- Reservation system (1)
- Resistive temperature detector (1)
- Resolvent Operator (1)
- Resonance-mode measurement (1)
- Response Surface Method (1)
- Retinal vessel analysis (1)
- Retinal vessels (1)
- Robotic rehabilitation (1)
- Rohr (1)
- Rohrbruch (1)
- Rotary encoder (1)
- Rotator cuff (1)
- Running (1)
- S-FEM (1)
- SFCW (1)
- SOA (1)
- SSE) JEL : O33 (1)
- ScaLAPACK (1)
- Schwammknochen (1)
- Seismic design (1)
- Seismic loading (1)
- Selective Catalytic Reduction (1)
- Self-driving (1)
- Semi-parametric random censorship model (1)
- Septic cardiomyopathy (1)
- Services (1)
- Shakedown (1)
- Shakedown criterion (1)
- Shoulder (1)
- Shunting (1)
- Silk fibroin (1)
- Simultaneous determination (1)
- Skeletal muscle (1)
- Slab deflection (1)
- Small Aral Sea (1)
- Small spacecraft (1)
- Snow (1)
- Sn₃O₄ (1)
- Soft independent modeling of class analogy (1)
- Software and systems modeling (1)
- Solar sail (1)
- Solitary waves (1)
- Sound Pressure Level (1)
- Source term (1)
- Spectroscopy (1)
- Spleen (1)
- Stahl (1)
- Steel industry (1)
- Stenotrophomonas maltophilia (1)
- Sterilisation process (1)
- Stochastic Programming (1)
- Streptomyces griseus (1)
- Streptomyces lividans (1)
- Stress concentrations (1)
- Structural design (1)
- Strukturanalyse (1)
- Subclacial exploration (1)
- Subglacial lakes (1)
- Surface imprinted polymer (1)
- Surgical Navigation and Robotics (1)
- Surgical staplers (1)
- Survival analysis (1)
- Suspension bridge (1)
- TMV adsorption (1)
- TOF PET (1)
- Tank (1)
- Targeted radionuclide therapy (TRT) (1)
- Ta₂O₅ gate (1)
- Technical Operations Research (1)
- Technical Operations Research (TOR) (1)
- Telecommunication (1)
- Temperaturabhängigkeit (1)
- Tendon Rupture (1)
- Tendon properties (1)
- Tendons (1)
- Tension (1)
- Thermal conductivity (1)
- Thin shell finite elements (1)
- Tinetti test (1)
- Tissue Engineering (1)
- Tobacco mosaic virus (TMV) (1)
- Tomography (1)
- Tool support (1)
- Trading Behavior (1)
- Traglast (1)
- Train composition (1)
- Trajectories (1)
- Transfer impedance (1)
- Transformation (1)
- Transient flux distribution (1)
- Transmission Eigenvalues (1)
- Trapeze effect (1)
- Two-phase modelling (1)
- Typographie (1)
- USP (1)
- Uktrahigh field MRI (1)
- Ultrasound (1)
- Uncertainty (1)
- Uniaxial compression test (1)
- Unmanned aerial vehicles (1)
- Unreinforced masonry buildings (1)
- Unsteady aerodynamics (1)
- Uracil-phosphoribosyltransferase (1)
- User study (1)
- Utilization improvement (1)
- VM (1)
- VOF (1)
- VOP compression (1)
- Vapnik–Čhervonenkis class (1)
- Variable height stapler design (1)
- Vascular response (1)
- Vasomotions (1)
- Velocity (1)
- Vertebroplastie (1)
- Vertebroplasty (1)
- Vertex cover (1)
- Vibrio natriegens (1)
- Virtual reality (1)
- Virtuelle Maschine (1)
- Viscous flow (1)
- Viskose Strömung (1)
- Viskosität (1)
- Visual field asymmetry (1)
- Voice assessment (1)
- Volterra integral equation (1)
- Volume of confidence regions (1)
- Volume status (1)
- Wastewater (1)
- Water Distribution (1)
- Water Supply Networks (1)
- Weak organic acids (1)
- Wiegand sensor (1)
- Wind milling (1)
- Wind tunnel experiments (1)
- Wireless Networks (1)
- Wolff's Law (1)
- Wolffsches Gesetz (1)
- Wundheilung (1)
- XOR (1)
- Zeta potential (1)
- Zug-Druck Belastung (1)
- acetoin (1)
- acetoin reductase (1)
- achilles tendon (1)
- actin cytoskeleton (1)
- actuator-sensor system (1)
- adaptive systems (1)
- adipose-derived stromal cells (ASCs) (1)
- adsorption (1)
- agility (1)
- alcoholic beverages (1)
- allocation (1)
- alternierend Verformbarkeit (1)
- aminooctanethiol (1)
- amperometric biosensors (1)
- anaesthetic complications (1)
- anammox (1)
- anisotropy (1)
- annealing (1)
- aortic perfusion (1)
- aquaculture (1)
- aromatic amines (1)
- artificial intelligence (1)
- artificial olfactory image (1)
- aseptic parameters (1)
- aspergillus (1)
- assistance system (1)
- asymptotic relative efficiency (1)
- atomic layer deposition (1)
- automated vehicles (1)
- automotive (1)
- autonomous navigation (1)
- availability (1)
- barium strontium titanate (1)
- batteries and fuel cells (1)
- bi-enzyme biosensor (1)
- biaxial tensile experiment (1)
- bicharacteristics (1)
- bio-methane (1)
- bioavailability (1)
- bioburdens (1)
- biocompatible (1)
- biocompatible materials (1)
- biodegradabl (1)
- biodegradable electronic devices (1)
- biodegradable polymers (1)
- biofilms (1)
- biological dosimeter (1)
- biomechanics (1)
- biomethane (1)
- biopotential electrodes (1)
- biosensor (1)
- body imaging at 7 T MRI (1)
- body imaging at UHF MRI (1)
- body limbs (1)
- bone density (1)
- bone structure (1)
- bootstrap (1)
- borefields (1)
- borehole disposal (1)
- brachytherapy (1)
- building energy modelling (1)
- building energy simulation (1)
- burst pressure (1)
- burst tests (1)
- business culture (1)
- calorimetric gas sensor (1)
- calorimetric gas sensor;hydrogen peroxide;wireless sensor system (1)
- cancellous bone (1)
- capacitive EIS sensor (1)
- capacitive electrolyte–insulator–semiconductor sensors (1)
- capacitive model (1)
- carbon dioxide removal (1)
- carbon electrodes (1)
- cardiac gating (1)
- cardiomyocyte biomechanics (1)
- cardiovascular MR imaging (1)
- catalytic metal (1)
- cell aerosolization (1)
- cell atomization (1)
- central symmetry test (1)
- cerebral small vessel disease (1)
- chance constrained programming (1)
- change (1)
- change management (1)
- chemical sensor (1)
- chip-based sensor setup (1)
- churches (1)
- civil engineering (1)
- climate change (1)
- climate neutrality (1)
- coculture (1)
- cognitive impairment (1)
- coherent structures (1)
- colorization (1)
- community dwelling (1)
- complete block symmetry (1)
- compression behavior (1)
- computational fluid dynamics analysis (1)
- concentrating collector (1)
- conditional excess distribution (1)
- conditional expectation principle (1)
- confidence interval (1)
- connected automated vehicles (1)
- connective tissue (1)
- constitutive modeling (1)
- contactless conductivity sensor (1)
- control gate (1)
- corporate sustainability (1)
- correlation (1)
- coupled Néel–Brownian relaxation dynamics (1)
- covariance principle (1)
- critical (1)
- crop yield (1)
- crystallization (1)
- cyber-physical production systems (1)
- dam-break (1)
- debris flow (1)
- deficit irrigation (1)
- dental trauma (1)
- deserts (1)
- design of technical systems (1)
- detection of charged macromolecules (1)
- detergent protease (1)
- dialysis (1)
- difficult airway (1)
- digital factory (1)
- digital twin (1)
- direct air capture (1)
- direct method (1)
- disposal facility (1)
- distorted element (1)
- distribution grid simulation (1)
- diversity management (1)
- double-lumen tube intubation (1)
- drag force (1)
- drop jump (1)
- drug metabolising enzymes (1)
- drug–drug interactions (1)
- e-mobility (1)
- eVTOL development (1)
- eVTOL safety (1)
- earthquake engineering (1)
- ecological structure (1)
- economics (1)
- efficiency side-effects (1)
- eigensolvers (1)
- elastic scattering (1)
- elastic solids (1)
- elastomers (1)
- electrical conductivity of liquids (1)
- electrocardiogram (1)
- electrolyte-insulator semiconductor sensor (EIS) (1)
- electrolyte-insulator-semiconductor capacitors (1)
- electromyography (1)
- electronic nose (1)
- electrospinning (1)
- encapsulation materials (1)
- endoluminal (1)
- endospores (1)
- energy (1)
- energy absorption (1)
- energy dissipation (1)
- energy transfer (1)
- engineering (1)
- entrepreneurship education (1)
- enzymatic (bio)degradation (1)
- enzymatic biosensor (1)
- enzyme cascade (1)
- enzyme kinetics (1)
- enzyme-logic gate (1)
- epithelization (1)
- equivalent circuit (1)
- equivalent stiffness (1)
- event-based simulation (1)
- exchangeability test (1)
- exopolysaccharides (1)
- experimental evaluation (1)
- extracorporeal membrane oxygenation (1)
- eye movement modelling examples (1)
- fatigue analyses (1)
- fibers (1)
- fibroin (1)
- field-effect structure (1)
- filamentous fungi (1)
- flaw (1)
- force generation (1)
- forecast (1)
- forehead EEG (1)
- fortschreitende plastische Deformation (1)
- frequency mixing (1)
- fuel cell vehicle (1)
- functional data (1)
- ga-doping (1)
- gait (1)
- gamification (1)
- garnet solid electrolyte (1)
- gas sensor (1)
- gaseous hydrogen peroxide (1)
- genetic algorithm (1)
- genome engineering (1)
- geological disposal (1)
- geothermal (1)
- global optimization (1)
- glucose (1)
- glucose oxidase (GOx) (1)
- glycine (1)
- goodness-of-fit test (1)
- granular silo (1)
- graphene oxide (1)
- grey energy (1)
- halotolerant protease (1)
- harmonic radar tags (1)
- healthy aging (1)
- heat demand (1)
- heat transfer coefficient (1)
- heating system (1)
- heavy metals (1)
- hiPS cardiomyocytes (1)
- high field MR imaging (1)
- high-alkaline subtilisin (1)
- high-intensity exercise (1)
- high-k material (1)
- horseradish peroxidase (HRP) (1)
- huge dimensional data (1)
- human dermal fibroblasts (1)
- human metabolites (1)
- humic acid (1)
- hydraulic modelling (1)
- hydrogel (1)
- hydrogels (1)
- hydroxylation (1)
- hyper-gravity (1)
- hyperelastic (1)
- hypo-gravity (1)
- hypoplasticity (1)
- ignition (1)
- impulsive effects (1)
- in-ear EEG (1)
- in-situ monitoring (1)
- incontinence (1)
- independence test (1)
- industrial agents (1)
- industry 4.0 (1)
- infill strategy (1)
- innovation management (1)
- integrated transmit coil arrays (1)
- intelligent control (1)
- intelligent energy management (1)
- intraclass correlation coefficient (1)
- irradiation (1)
- jevons paradox (1)
- key performance indicators (1)
- konvexe Optimierung (1)
- lable-free detection (1)
- large language models (1)
- large-scale inspection (1)
- layer-by-layer technique (1)
- legal obligations (1)
- light-addressable electrode (1)
- light-addressing technologies (1)
- lignite (1)
- limit load (1)
- lipopolysaccharide (1)
- lipopolysaccharides (1)
- liquid-storage tank (1)
- liquid-structure interaction (1)
- literature (1)
- lizards (1)
- load limit (1)
- low-rank coal (1)
- machine learning (1)
- macro-element (1)
- magnetic actuation (1)
- magnetic beads (1)
- magnetic biosensing (1)
- magnetic relaxation (1)
- magnetic resonance imaging (1)
- magnetic sandwich immunoassay (1)
- magnetic sensing (1)
- magnetic sensors (1)
- magnetic separation (1)
- magnetic tweezers (1)
- magnetophoretic velocity (1)
- mainstream deammonification (1)
- management (1)
- manufacturing (1)
- manufacturing data model (1)
- marketing (1)
- mathematical optimization (1)
- mechanical buffer (1)
- mechanical properties (1)
- metagenomics (1)
- metal-oxide-semiconductor structure (1)
- method of fundamental solutions (1)
- microbial diversity (1)
- micromagnetic simulation (1)
- micronutrients (1)
- microplasma (1)
- microwave (MW) plasma (1)
- microwave measurements (1)
- mix flexibility (1)
- mixed-integer linear programming (1)
- mobile manipulation (1)
- model performance (1)
- motivation (1)
- multi-agent systems (1)
- multi-functional material (1)
- multi-sensing platform (1)
- multianalyte detection (1)
- multinomial distribution (1)
- multiparametric immunoassays (1)
- multiplex detection (1)
- multivariate normal distribution (1)
- muscle mechanics (1)
- nanobelts (1)
- nanomaterials (1)
- nanoparticle coverage (1)
- nanostructured carbonized plant parts (1)
- nanostrukturierte carbonisierte Pflanzenteile (1)
- naphtols (1)
- negative emissions (1)
- neutrons (1)
- next generation network (1)
- nitrogen elimination (1)
- non-simplex S-FEM elements (1)
- nonlinear VNA measurements (1)
- nonlinear radar (1)
- nonlinear transient analyses (1)
- novel photoexcitation method (1)
- nuclear waste (1)
- numerical model (1)
- on-chip integrated addressable EISCAP sensors (1)
- onion (1)
- optical fibers (1)
- optical sensor setup (1)
- optical spore trapping (1)
- optical trapping (1)
- optimization (1)
- optimization system (1)
- organosilanes (1)
- overload (1)
- oxidative stable protease (1)
- pH sensors (1)
- parabolic flight (1)
- penicillin (1)
- performance analysis (1)
- performance testing (1)
- phenols (1)
- phonocardiogram (1)
- photoelectrochemistry (1)
- physical model (1)
- physiology (1)
- pipes (1)
- plant scanner (1)
- plant stress (1)
- plant virus detection (1)
- plasma jet (1)
- plug-based microfluidic device (1)
- point-focussing system (1)
- poly(d, l-lactic acid) (1)
- polyaniline (1)
- polyaspartic acid (1)
- polyetheretherketone (1)
- polyetheretherketone (PEEK) (1)
- polystyrene sulfonate (1)
- porous materials (1)
- portfolio risk (1)
- power-to-gas (1)
- prevention (1)
- product bundling (1)
- product liability (1)
- production planning and control (1)
- programming (1)
- prostate cancer (1)
- prostatectomy (1)
- proton therapy (1)
- protons (1)
- psychosocial (1)
- pullulan (1)
- quality of life (1)
- random effects (1)
- random effects meta-regression model (1)
- ratchetting (1)
- raytracing (1)
- recombinant expression (1)
- rehabilitation (1)
- relative dosimetry (1)
- reliability analysis (1)
- reliability of structures (1)
- remote sensing (1)
- research association (1)
- resilience (1)
- resource abundance (1)
- retention time (1)
- retinal microvasculature (1)
- retinal vessels (1)
- review (1)
- rollout (1)
- rubber (1)
- running (1)
- sEMG (1)
- sarcomere operating length (1)
- scanned light pulse technique (1)
- seismic response (1)
- semantic role labeling (1)
- separable Hilbert space (1)
- series elastic element behavior (1)
- service-oriented architectures (1)
- shakedown analyses (1)
- shotgun sequencing (1)
- shoulder (1)
- silanization (1)
- simulation (1)
- sizing (1)
- slum classification (1)
- smart-charging (1)
- smooth muscle contraction (1)
- socio-economic welfare (1)
- soil amendment (1)
- soil health (1)
- soil remediation (1)
- solar process heat (1)
- solid-state battery (1)
- spatial resolution (1)
- speaker attribution (1)
- spore kill rate (1)
- sprint start (1)
- standard error of measurement (1)
- sterilisation (1)
- sterility (1)
- sterility tests (1)
- sterilization (1)
- sterilization conditions (1)
- sterilization efficacy (1)
- sterilization methods (1)
- stiffness (1)
- stochastic optimization (1)
- stochastic programming (1)
- strain energy function (1)
- stretch reflex (1)
- stretch-shortening cycle (1)
- structure-soil-structure interaction (1)
- superabsorbent polymers (1)
- superparamagnetic bead (1)
- superparamagnetic nanoparticles (1)
- supramolecular structures (1)
- surface functionalization (1)
- surface modification (1)
- surface-orthogonal path planning (1)
- survival (1)
- swelling properties (1)
- swimming (1)
- system optimization (1)
- system synthesis (1)
- systematic (1)
- technical operations research (1)
- technology planning (1)
- telecommunication (1)
- temperature (1)
- tendon rupture (1)
- tension–torsion loading (1)
- test-retest reliability (1)
- theory and modeling (1)
- thermal dose (1)
- thermal ratcheting (1)
- thermometry (1)
- tilted constant illumination (1)
- tissue temperature (1)
- titanium dioxide photoanode (1)
- transmit antenna arrays (1)
- transponder (1)
- transporters (1)
- tri-lineage differentiation (1)
- truss (1)
- turnip vein clearing virus (TVCV) (1)
- twin-fluid atomizer (1)
- ultrasonography (1)
- ultrathin gate insulators (1)
- uniformly most powerful invariant test (1)
- unloading (1)
- urease (1)
- validation methods (1)
- vault (1)
- vessels (1)
- video learning (1)
- videolaryngoscopy (1)
- virgin passive (1)
- virtual clean room (1)
- viscoelasticity (1)
- visualization (1)
- volume flexibility (1)
- walking (1)
- walking gait (1)
- wastewater (1)
- water economy (1)
- water supply design (1)
- wind turbine production (1)
- wound healing (1)
- yield (1)
- yield stress (1)
- α-aminoacylase (1)
- ε-lysine acylase (1)
Subglacial environments on Earth offer important analogs to Ocean World targets in our solar system. These unique microbial ecosystems remain understudied due to the challenges of access through thick glacial ice (tens to hundreds of meters). Additionally, sub-ice collections must be conducted in a clean manner to ensure sample integrity for downstream microbiological and geochemical analyses. We describe the field-based cleaning of a melt probe that was used to collect brine samples from within a glacier conduit at Blood Falls, Antarctica, for geomicrobiological studies. We used a thermoelectric melting probe called the IceMole that was designed to be minimally invasive in that the logistical requirements in support of drilling operations were small and the probe could be cleaned, even in a remote field setting, so as to minimize potential contamination. In our study, the exterior bioburden on the IceMole was reduced to levels measured in most clean rooms, and below that of the ice surrounding our sampling target. Potential microbial contaminants were identified during the cleaning process; however, very few were detected in the final englacial sample collected with the IceMole and were present in extremely low abundances (∼0.063% of 16S rRNA gene amplicon sequences). This cleaning protocol can help minimize contamination when working in remote field locations, support microbiological sampling of terrestrial subglacial environments using melting probes, and help inform planetary protection challenges for Ocean World analog mission concepts.
Methane is a valuable energy source helping to mitigate the growing energy demand worldwide. However, as a potent greenhouse gas, it has also gained additional attention due to its environmental impacts. The biological production of methane is performed primarily hydrogenotrophically from H2 and CO2 by methanogenic archaea. Hydrogenotrophic methanogenesis also represents a great interest with respect to carbon re-cycling and H2 storage. The most significant carbon source, extremely rich in complex organic matter for microbial degradation and biogenic methane production, is coal. Although interest in enhanced microbial coalbed methane production is continuously increasing globally, limited knowledge exists regarding the exact origins of the coalbed methane and the associated microbial communities, including hydrogenotrophic methanogens. Here, we give an overview of hydrogenotrophic methanogens in coal beds and related environments in terms of their energy production mechanisms, unique metabolic pathways, and associated ecological functions.
Ga-doped Li7La3Zr2O12 garnet solid electrolytes exhibit the highest Li-ion conductivities among the oxide-type garnet-structured solid electrolytes, but instabilities toward Li metal hamper their practical application. The instabilities have been assigned to direct chemical reactions between LiGaO2 coexisting phases and Li metal by several groups previously. Yet, the understanding of the role of LiGaO2 in the electrochemical cell and its electrochemical properties is still lacking. Here, we are investigating the electrochemical properties of LiGaO2 through electrochemical tests in galvanostatic cells versus Li metal and complementary ex situ studies via confocal Raman microscopy, quantitative phase analysis based on powder X-ray diffraction, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and electron energy loss spectroscopy. The results demonstrate considerable and surprising electrochemical activity, with high reversibility. A three-stage reaction mechanism is derived, including reversible electrochemical reactions that lead to the formation of highly electronically conducting products. The results have considerable implications for the use of Ga-doped Li7La3Zr2O12 electrolytes in all-solid-state Li-metal battery applications and raise the need for advanced materials engineering to realize Ga-doped Li7La3Zr2O12for practical use.
The thermal conductivity of components manufactured using Laser Powder Bed Fusion (LPBF), also called Selective Laser Melting (SLM), plays an important role in their processing. Not only does a reduced thermal conductivity cause residual stresses during the process, but it also makes subsequent processes such as the welding of LPBF components more difficult. This article uses 316L stainless steel samples to investigate whether and to what extent the thermal conductivity of specimens can be influenced by different LPBF parameters. To this end, samples are set up using different parameters, orientations, and powder conditions and measured by a heat flow meter using stationary analysis. The heat flow meter set-up used in this study achieves good reproducibility and high measurement accuracy, so that comparative measurements between the various LPBF influencing factors to be tested are possible. In summary, the series of measurements show that the residual porosity of the components has the greatest influence on conductivity. The degradation of the powder due to increased recycling also appears to be detectable. The build-up direction shows no detectable effect in the measurement series.
In this work, the effect of low air relative humidity on the operation of a polymer electrolyte membrane fuel cell is investigated. An innovative method through performing in situ electrochemical impedance spectroscopy is utilised to quantify the effect of inlet air relative humidity at the cathode side on internal ionic resistances and output voltage of the fuel cell. In addition, algorithms are developed to analyse the electrochemical characteristics of the fuel cell. For the specific fuel cell stack used in this study, the membrane resistance drops by over 39 % and the cathode side charge transfer resistance decreases by 23 % after increasing the humidity from 30 % to 85 %, while the results of static operation also show an increase of ∼2.2 % in the voltage output after increasing the relative humidity from 30 % to 85 %. In dynamic operation, visible drying effects occur at < 50 % relative humidity, whereby the increase of the air side stoichiometry increases the drying effects. Furthermore, other parameters, such as hydrogen humidification, internal stack structure, and operating parameters like stoichiometry, pressure, and temperature affect the overall water balance. Therefore, the optimal humidification range must be determined by considering all these parameters to maximise the fuel cell performance and durability. The results of this study are used to develop a health management system to ensure sufficient humidification by continuously monitoring the fuel cell polarisation data and electrochemical impedance spectroscopy indicators.
Critical quantitative evaluation of integrated health management methods for fuel cell applications
(2024)
Online fault diagnostics is a crucial consideration for fuel cell systems, particularly in mobile applications, to limit downtime and degradation, and to increase lifetime. Guided by a critical literature review, in this paper an overview of Health management systems classified in a scheme is presented, introducing commonly utilised methods to diagnose FCs in various applications. In this novel scheme, various Health management system methods are summarised and structured to provide an overview of existing systems including their associated tools. These systems are classified into four categories mainly focused on model-based and non-model-based systems. The individual methods are critically discussed when used individually or combined aimed at further understanding their functionality and suitability in different applications. Additionally, a tool is introduced to evaluate methods from each category based on the scheme presented. This tool applies the technique of matrix evaluation utilising several key parameters to identify the most appropriate methods for a given application. Based on this evaluation, the most suitable methods for each specific application are combined to build an integrated Health management system.
Meitner-Auger-electron emitters have a promising potential for targeted radionuclide therapy of cancer because of their short range and the high linear energy transfer of Meitner-Auger-electrons (MAE). One promising MAE candidate is 197m/gHg with its half-life of 23.8 h and 64.1 h, respectively, and high MAE yield. Gold nanoparticles (AuNPs) that are labelled with 197m/gHg could be a helpful tool for radiation treatment of glioblastoma multiforme when infused into the surgical cavity after resection to prevent recurrence. To produce such AuNPs, 197m/gHg was embedded into pristine AuNPs. Two different syntheses were tested starting from irradiated gold containing trace amounts of 197m/gHg. When sodium citrate was used as reducing agent, no 197m/gHg labelled AuNPs were formed, but with tannic acid, 197m/gHg labeled AuNPs were produced. The method was optimized by neutralizing the pH (pH = 7) of the Au/197m/gHg solution, which led to labelled AuNPs with a size of 12.3 ± 2.0 nm as measured by transmission electron microscopy. The labelled AuNPs had a concentration of 50 μg (gold)/mL with an activity of 151 ± 93 kBq/mL (197gHg, time corrected to the end of bombardment).
We present the production of 58mCo on a small, 13 MeV medical cyclotron utilizing a siphon style liquid target system. Different concentrated iron(III)-nitrate solutions of natural isotopic distribution were irradiated at varying initial pressures and subsequently separated by solid phase extraction chromatography. The radio cobalt (58m/gCo and 56Co) was successfully produced with saturation activities of (0.35 ± 0.03) MBq μA−1 for 58mCo with a separation recovery of (75 ± 2) % of cobalt after one separation step utilizing LN-resin.
Density reduction effects on the production of [11C]CO2 in Nb-body targets on a medical cyclotron
(2023)
Medical isotope production of 11C is commonly performed in gaseous targets. The power deposition of the proton beam during the irradiation decreases the target density due to thermodynamic mixing and can cause an increase of penetration depth and divergence of the proton beam. In order to investigate the difference how the target-body length influences the operation conditions and the production yield, a 12 cm and a 22 cm Nb-target body containing N2/O2 gas were irradiated using a 13 MeV proton cyclotron. It was found that the density reduction has a large influence on the pressure rise during irradiation and the achievable radioactive yield. The saturation activity of [11C]CO2 for the long target (0.083 Ci/μA) is about 10% higher than in the short target geometry (0.075 Ci/μA).
Elastic transmission eigenvalues and their computation via the method of fundamental solutions
(2020)
A stabilized version of the fundamental solution method to catch ill-conditioning effects is investigated with focus on the computation of complex-valued elastic interior transmission eigenvalues in two dimensions for homogeneous and isotropic media. Its algorithm can be implemented very shortly and adopts to many similar partial differential equation-based eigenproblems as long as the underlying fundamental solution function can be easily generated. We develop a corroborative approximation analysis which also implicates new basic results for transmission eigenfunctions and present some numerical examples which together prove successful feasibility of our eigenvalue recovery approach.
The low-pressure system Bernd involved extreme rainfalls in the Western part of Germany in July 2021,
resulting in major floods, severe damages and a tremendous number of casualties. Such extreme events
are rare and full flood protection can never be ensured with reasonable financial means. But still, this
event must be starting point to reconsider current design concepts. This article aims at sharing some
thoughts on potential hazards, the selection of return periods and remaining risk with the focus on Germany.
Direct sampling method via Landweber iteration for an absorbing scatterer with a conductive boundary
(2024)
In this paper, we consider the inverse shape problem of recovering isotropic scatterers with a conductive boundary condition. Here, we assume that the measured far-field data is known at a fixed wave number. Motivated by recent work, we study a new direct sampling indicator based on the Landweber iteration and the factorization method. Therefore, we prove the connection between these reconstruction methods. The method studied here falls under the category of qualitative reconstruction methods where an imaging function is used to recover the absorbing scatterer. We prove stability of our new imaging function as well as derive a discrepancy principle for recovering the regularization parameter. The theoretical results are verified with numerical examples to show how the reconstruction performs by the new Landweber direct sampling method.
We consider the numerical approximation of second-order semi-linear parabolic stochastic partial differential equations interpreted in the mild sense which we solve on general two-dimensional domains with a C² boundary with homogeneous Dirichlet boundary conditions. The equations are driven by Gaussian additive noise, and several Lipschitz-like conditions are imposed on the nonlinear function. We discretize in space with a spectral Galerkin method and in time using an explicit Euler-like scheme. For irregular shapes, the necessary Dirichlet eigenvalues and eigenfunctions are obtained from a boundary integral equation method. This yields a nonlinear eigenvalue problem, which is discretized using a boundary element collocation method and is solved with the Beyn contour integral algorithm. We present an error analysis as well as numerical results on an exemplary asymmetric shape, and point out limitations of the approach.
Analysis and computation of the transmission eigenvalues with a conductive boundary condition
(2022)
We provide a new analytical and computational study of the transmission eigenvalues with a conductive boundary condition. These eigenvalues are derived from the scalar inverse scattering problem for an inhomogeneous material with a conductive boundary condition. The goal is to study how these eigenvalues depend on the material parameters in order to estimate the refractive index. The analytical questions we study are: deriving Faber–Krahn type lower bounds, the discreteness and limiting behavior of the transmission eigenvalues as the conductivity tends to infinity for a sign changing contrast. We also provide a numerical study of a new boundary integral equation for computing the eigenvalues. Lastly, using the limiting behavior we will numerically estimate the refractive index from the eigenvalues provided the conductivity is sufficiently large but unknown.
An alternative method is presented to numerically compute interior elastic transmission eigenvalues for various domains in two dimensions. This is achieved by discretizing the resulting system of boundary integral equations in combination with a nonlinear eigenvalue solver. Numerical results are given to show that this new approach can provide better results than the finite element method when dealing with general domains.
The hot spots conjecture is only known to be true for special geometries. This paper shows numerically that the hot spots conjecture can fail to be true for easy to construct bounded domains with one hole. The underlying eigenvalue problem for the Laplace equation with Neumann boundary condition is solved with boundary integral equations yielding a non-linear eigenvalue problem. Its discretization via the boundary element collocation method in combination with the algorithm by Beyn yields highly accurate results both for the first non-zero eigenvalue and its corresponding eigenfunction which is due to superconvergence. Additionally, it can be shown numerically that the ratio between the maximal/minimal value inside the domain and its maximal/minimal value on the boundary can be larger than 1 + 10− 3. Finally, numerical examples for easy to construct domains with up to five holes are provided which fail the hot spots conjecture as well.
There is a very large number of very important situations which can be modeled with nonlinear parabolic partial differential equations (PDEs) in several dimensions. In general, these PDEs can be solved by discretizing in the spatial variables and transforming them into huge systems of ordinary differential equations (ODEs), which are very stiff. Therefore, standard explicit methods require a large number of iterations to solve stiff problems. But implicit schemes are computationally very expensive when solving huge systems of nonlinear ODEs. Several families of Extrapolated Stabilized Explicit Runge-Kutta schemes (ESERK) with different order of accuracy (3 to 6) are derived and analyzed in this work. They are explicit methods, with stability regions extended, along the negative real semi-axis, quadratically with respect to the number of stages s, hence they can be considered to solve stiff problems much faster than traditional explicit schemes. Additionally, they allow the adaptation of the step length easily with a very small cost.
Two new families of ESERK schemes (ESERK3 and ESERK6) are derived, and analyzed, in this work. Each family has more than 50 new schemes, with up to 84.000 stages in the case of ESERK6. For the first time, we also parallelized all these new variable step length and variable number of stages algorithms (ESERK3, ESERK4, ESERK5, and ESERK6). These parallelized strategies allow to decrease times significantly, as it is discussed and also shown numerically in two problems. Thus, the new codes provide very good results compared to other well-known ODE solvers. Finally, a new strategy is proposed to increase the efficiency of these schemes, and it is discussed the idea of combining ESERK families in one code, because typically, stiff problems have different zones and according to them and the requested tolerance the optimum order of convergence is different.
A second-order L-stable exponential time-differencing (ETD) method is developed by combining an ETD scheme with approximating the matrix exponentials by rational functions having real distinct poles (RDP), together with a dimensional splitting integrating factor technique. A variety of non-linear reaction-diffusion equations in two and three dimensions with either Dirichlet, Neumann, or periodic boundary conditions are solved with this scheme and shown to outperform a variety of other second-order implicit-explicit schemes. An additional performance boost is gained through further use of basic parallelization techniques.
In this article, a concept of implicit methods for scalar conservation laws in one or more spatial dimensions allowing also for source terms of various types is presented. This material is a significant extension of previous work of the first author (Breuß SIAM J. Numer. Anal. 43(3), 970–986 2005). Implicit notions are developed that are centered around a monotonicity criterion. We demonstrate a connection between a numerical scheme and a discrete entropy inequality, which is based on a classical approach by Crandall and Majda. Additionally, three implicit methods are investigated using the developed notions. Next, we conduct a convergence proof which is not based on a classical compactness argument. Finally, the theoretical results are confirmed by various numerical tests.
The inverse scattering problem for a conductive boundary condition and transmission eigenvalues
(2018)
In this paper, we consider the inverse scattering problem associated with an inhomogeneous media with a conductive boundary. In particular, we are interested in two problems that arise from this inverse problem: the inverse conductivity problem and the corresponding interior transmission eigenvalue problem. The inverse conductivity problem is to recover the conductive boundary parameter from the measured scattering data. We prove that the measured scatted data uniquely determine the conductivity parameter as well as describe a direct algorithm to recover the conductivity. The interior transmission eigenvalue problem is an eigenvalue problem associated with the inverse scattering of such materials. We investigate the convergence of the eigenvalues as the conductivity parameter tends to zero as well as prove existence and discreteness for the case of an absorbing media. Lastly, several numerical and analytical results support the theory and we show that the inside–outside duality method can be used to reconstruct the interior conductive eigenvalues.
The aim of the current study was to investigate the performance of integrated RF
transmit arrays with high channel count consisting of meander microstrip antennas
for body imaging at 7 T and to optimize the position and number of transmit ele-
ments. RF simulations using multiring antenna arrays placed behind the bore liner
were performed for realistic exposure conditions for body imaging. Simulations were
performed for arrays with as few as eight elements and for arrays with high channel
counts of up to 48 elements. The B1+ field was evaluated regarding the degrees of
freedom for RF shimming in the abdomen. Worst-case specific absorption rate
(SARwc ), SAR overestimation in the matrix compression, the number of virtual obser-
vation points (VOPs) and SAR efficiency were evaluated. Constrained RF shimming
was performed in differently oriented regions of interest in the body, and the devia-
tion from a target B1+ field was evaluated. Results show that integrated multiring
arrays are able to generate homogeneous B1+ field distributions for large FOVs, espe-
cially for coronal/sagittal slices, and thus enable body imaging at 7 T with a clinical
workflow; however, a low duty cycle or a high SAR is required to achieve homoge-
neous B1+ distributions and to exploit the full potential. In conclusion, integrated
arrays allow for high element counts that have high degrees of freedom for the pulse
optimization but also produce high SARwc , which reduces the SAR accuracy in the
VOP compression for low-SAR protocols, leading to a potential reduction in array
performance. Smaller SAR overestimations can increase SAR accuracy, but lead to a
high number of VOPs, which increases the computational cost for VOP evaluation
and makes online SAR monitoring or pulse optimization challenging. Arrays with
interleaved rings showed the best results in the study.
In this work, we present a compact, bifunctional chip-based sensor setup that measures the temperature and electrical conductivity of water samples, including specimens from rivers and channels, aquaculture, and the Atlantic Ocean. For conductivity measurements, we utilize the impedance amplitude recorded via interdigitated electrode structures at a single triggering frequency. The results are well in line with data obtained using a calibrated reference instrument. The new setup holds for conductivity values spanning almost two orders of magnitude (river versus ocean water) without the need for equivalent circuit modelling. Temperature measurements were performed in four-point geometry with an on-chip platinum RTD (resistance temperature detector) in the temperature range between 2 °C and 40 °C, showing no hysteresis effects between warming and cooling cycles. Although the meander was not shielded against the liquid, the temperature calibration provided equivalent results to low conductive Milli-Q and highly conductive ocean water. The sensor is therefore suitable for inline and online monitoring purposes in recirculating aquaculture systems.
Magnetic Resonance Imaging (MRI) of moving organs requires synchronization with physiological motion or flow, which dictate the viable window for data acquisition. To meet this challenge, this study proposes an acoustic gating device (ACG) that employs acquisition and processing of acoustic signals for synchronization while providing MRI compatibility, immunity to interferences with electro-magnetic and acoustic fields and suitability for MRI at high magnetic field strengths. The applicability and robustness of the acoustic gating approach is examined in a pilot study, where it substitutes conventional ECG-gating for cardiovascular MR. The merits and limitations of the ACG approach are discussed. Implications for MR imaging in the presence of physiological motion are considered including synchronization with other structure- or motion borne sounds.
As one class of molecular imprinted polymers (MIPs), surface imprinted polymer (SIP)-based biosensors show great potential in direct whole-bacteria detection. Micro-contact imprinting, that involves stamping the template bacteria immobilized on a substrate into a pre-polymerized polymer matrix, is the most straightforward and prominent method to obtain SIP-based biosensors. However, the major drawbacks of the method arise from the requirement for fresh template bacteria and often non-reproducible bacteria distribution on the stamp substrate. Herein, we developed a positive master stamp containing photolithographic mimics of the template bacteria (E. coli) enabling reproducible fabrication of biomimetic SIP-based biosensors without the need for the “real” bacteria cells. By using atomic force and scanning electron microscopy imaging techniques, respectively, the E. coli-capturing ability of the SIP samples was tested, and compared with non-imprinted polymer (NIP)-based samples and control SIP samples, in which the cavity geometry does not match with E. coli cells. It was revealed that the presence of the biomimetic E. coli imprints with a specifically designed geometry increases the sensor E. coli-capturing ability by an “imprinting factor” of about 3. These findings show the importance of geometry-guided physical recognition in bacterial detection using SIP-based biosensors. In addition, this imprinting strategy was employed to interdigitated electrodes and QCM (quartz crystal microbalance) chips. E. coli detection performance of the sensors was demonstrated with electrochemical impedance spectroscopy (EIS) and QCM measurements with dissipation monitoring technique (QCM-D).
This study demonstrates the feasibility of applying free-breathing, cardiac-gated, susceptibility-weighted fast spin-echo imaging together with black blood preparation and navigator-gated respiratory motion compensation for anatomically accurate T₂ mapping of the heart. First, T₂ maps are presented for oil phantoms without and with respiratory motion emulation (T₂ = (22.1 ± 1.7) ms at 1.5 T and T₂ = (22.65 ± 0.89) ms at 3.0 T). T₂ relaxometry of a ferrofluid revealed relaxivities of R2 = (477.9 ± 17) mM⁻¹s⁻¹ and R2 = (449.6 ± 13) mM⁻¹s⁻¹ for UFLARE and multiecho gradient-echo imaging at 1.5 T. For inferoseptal myocardial regions mean T₂ values of 29.9 ± 6.6 ms (1.5 T) and 22.3 ± 4.8 ms (3.0 T) were estimated. For posterior myocardial areas close to the vena cava T₂-values of 24.0 ± 6.4 ms (1.5 T) and 15.4 ± 1.8 ms (3.0 T) were observed. The merits and limitations of the proposed approach are discussed and its implications for cardiac and vascular T₂-mapping are considered.
The simultaneous assessment of glottal dynamics and larynx position can be beneficial for the diagnosis of disordered voice or speech production and swallowing. Up to now, methods either concentrate on assessment of the glottis opening using optical, acoustical or electrical (electroglottography, EGG) methods, or on visualisation of the larynx position using ultrasound, computer tomography or magnetic resonance imaging techniques.
The method presented here makes use of a time-multiplex measurement approach of space-resolved transfer impedances through the larynx. The fast sequence of measurements allows a quasi simultaneous assessment of both larynx position and EGG signal using up to 32 transmit–receive signal paths. The system assesses the dynamic opening status of the glottis as well as the vertical and back/forward motion of the larynx.
Two electrode-arrays are used for the measurement of the electrical transfer impedance through the neck in different directions. From the acquired data the global and individual conductivity is calculated as well as a 2D point spatial representation of the minimum impedance.
The position information is shown together with classical EGG signals allowing a synchronous visual assessment of glottal area and larynx position. A first application to singing voice analysis is presented that indicate a high potential of the method for use as a non-invasive tool in the diagnosis of voice, speech, and swallowing disorders.
Objectives
Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T.
Methods
A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated.
Results
All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm.
Conclusions
This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T.
Background
To demonstrate the applicability of acoustic cardiac triggering (ACT) for imaging of the heart at ultrahigh magnetic fields (7.0 T) by comparing phonocardiogram, conventional vector electrocardiogram (ECG) and traditional pulse oximetry (POX) triggered 2D CINE acquisitions together with (i) a qualitative image quality analysis, (ii) an assessment of the left ventricular function parameter and (iii) an examination of trigger reliability and trigger detection variance derived from the signal waveforms.
Results
ECG was susceptible to severe distortions at 7.0 T. POX and ACT provided waveforms free of interferences from electromagnetic fields or from magneto-hydrodynamic effects. Frequent R-wave mis-registration occurred in ECG-triggered acquisitions with a failure rate of up to 30% resulting in cardiac motion induced artifacts. ACT and POX triggering produced images free of cardiac motion artefacts. ECG showed a severe jitter in the R-wave detection. POX also showed a trigger jitter of approximately Δt = 72 ms which is equivalent to two cardiac phases. ACT showed a jitter of approximately Δt = 5 ms only. ECG waveforms revealed a standard deviation for the cardiac trigger offset larger than that observed for ACT or POX waveforms.
Image quality assessment showed that ACT substantially improved image quality as compared to ECG (image quality score at end-diastole: ECG = 1.7 ± 0.5, ACT = 2.4 ± 0.5, p = 0.04) while the comparison between ECG vs. POX gated acquisitions showed no significant differences in image quality (image quality score: ECG = 1.7 ± 0.5, POX = 2.0 ± 0.5, p = 0.34).
Conclusions
The applicability of acoustic triggering for cardiac CINE imaging at 7.0 T was demonstrated. ACT's trigger reliability and fidelity are superior to that of ECG and POX. ACT promises to be beneficial for cardiovascular magnetic resonance at ultra-high field strengths including 7.0 T.
Purpose
To design and evaluate a four-channel cardiac transceiver coil array for functional cardiac imaging at 7T.
Materials and Methods
A four-element cardiac transceiver surface coil array was developed with two rectangular loops mounted on an anterior former and two rectangular loops on a posterior former. specific absorption rate (SAR) simulations were performed and a Burn:x-wiley:10531807:media:JMRI22451:tex2gif-stack-1 calibration method was applied prior to obtain 2D FLASH CINE (mSENSE, R = 2) images from nine healthy volunteers with a spatial resolution of up to 1 × 1 × 2.5 mm3.
Results
Tuning and matching was found to be better than 10 dB for all subjects. The decoupling (S21) was measured to be >18 dB between neighboring loops, >20 dB for opposite loops, and >30 dB for other loop combinations. SAR values were well within the limits provided by the IEC. Imaging provided clinically acceptable signal homogeneity with an excellent blood-myocardium contrast applying the Burn:x-wiley:10531807:media:JMRI22451:tex2gif-stack-2 calibration approach.
Conclusion
A four-channel cardiac transceiver coil array for 7T was built, allowing for cardiac imaging with clinically acceptable signal homogeneity and an excellent blood-myocardium contrast. Minor anatomic structures, such as pericardium, mitral, and tricuspid valves and their apparatus, as well as trabeculae, were accurately delineated.
Objective
The purpose of this study is to (i) design a small and mobile Magnetic field ALert SEnsor (MALSE), (ii) to carefully evaluate its sensors to their consistency of activation/deactivation and sensitivity to magnetic fields, and (iii) to demonstrate the applicability of MALSE in 1.5 T, 3.0 T and 7.0 T MR fringe field environments.
Methods
MALSE comprises a set of reed sensors, which activate in response to their exposure to a magnetic field. The activation/deactivation of reed sensors was examined by moving them in/out of the fringe field generated by 7TMR.
Results
The consistency with which individual reed sensors would activate at the same field strength was found to be 100% for the setup used. All of the reed switches investigated required a substantial drop in ambient magnetic field strength before they deactivated.
Conclusions
MALSE is a simple concept for alerting MRI staff to a ferromagnetic object being brought into fringe magnetic fields which exceeds MALSEs activation magnetic field. MALSE can easily be attached to ferromagnetic objects within the vicinity of a scanner, thus creating a barrier for hazardous situations induced by ferromagnetic parts which should not enter the vicinity of an MR-system to occur.
Spontaneous language has rarely been subjected to neuroimaging studies. This study therefore introduces a newly developed method for the analysis of linguistic phenomena observed in continuous language production during fMRI.
Most neuroimaging studies investigating language have so far focussed on single word or — to a smaller extent — sentence processing, mostly due to methodological considerations. Natural language production, however, is far more than the mere combination of words to larger units. Therefore, the present study aimed at relating brain activation to linguistic phenomena like word-finding difficulties or syntactic completeness in a continuous language fMRI paradigm. A picture description task with special constraints was used to provoke hesitation phenomena and speech errors. The transcribed speech sample was segmented into events of one second and each event was assigned to one category of a complex schema especially developed for this purpose. The main results were: conceptual planning engages bilateral activation of the precuneus. Successful lexical retrieval is accompanied – particularly in comparison to unsolved word-finding difficulties – by the left middle and superior temporal gyrus. Syntactic completeness is reflected in activation of the left inferior frontal gyrus (IFG) (area 44). In sum, the method has proven to be useful for investigating the neural correlates of lexical and syntactic phenomena in an overt picture description task. This opens up new prospects for the analysis of spontaneous language production during fMRI.
Purpose:
To investigate the feasibility of using magnetohydrodynamic (MHD) effects for synchronization of magnetic resonance imaging (MRI) with the cardiac cycle.
Materials and Methods:
The MHD effect was scrutinized using a pulsatile flow phantom at B0 = 7.0 T. MHD effects were examined in vivo in healthy volunteers (n = 10) for B0 ranging from 0.05–7.0 T. Noncontrast-enhanced MR angiography (MRA) of the carotids was performed using a gated steady-state free-precession (SSFP) imaging technique in conjunction with electrocardiogram (ECG) and MHD synchronization.
Results:
The MHD potential correlates with flow velocities derived from phase contrast MRI. MHD voltages depend on the orientation between B0 and the flow of a conductive fluid. An increase in the interelectrode spacing along the flow increases the MHD potential. In vivo measurement of the MHD effect provides peak voltages of 1.5 mV for surface areas close to the common carotid artery at B0 = 7.0 T. Synchronization of MRI with the cardiac cycle using MHD triggering is feasible. MHD triggered MRA of the carotids at 3.0 T showed an overall image quality and richness of anatomic detail, which is comparable to ECG-triggered MRAs.
Conclusion:
This feasibility study demonstrates the use of MHD effects for synchronization of MR acquisitions with the cardiac cycle. J. Magn. Reson. Imaging 2012;36:364–372. © 2012 Wiley Periodicals, Inc.
Purpose
To design and evaluate a modular transceiver coil array with 32 independent channels for cardiac MRI at 7.0T.
Methods
The modular coil array comprises eight independent building blocks, each containing four transceiver loop elements. Numerical simulations were used for B1+ field homogenization and radiofrequency (RF) safety validation. RF characteristics were examined in a phantom study. The array's suitability for accelerated high spatial resolution two-dimensional (2D) FLASH CINE imaging of the heart was examined in a volunteer study.
Results
Transmission field adjustments and RF characteristics were found to be suitable for the volunteer study. The signal-to-noise intrinsic to 7.0T together with the coil performance afforded a spatial resolution of 1.1 × 1.1 × 2.5 mm3 for 2D CINE FLASH MRI, which is by a factor of 6 superior to standardized CINE protocols used in clinical practice at 1.5T. The 32-channel transceiver array supports one-dimensional acceleration factors of up to R = 4 without impairing image quality significantly.
Conclusion
The modular 32-channel transceiver cardiac array supports accelerated and high spatial resolution cardiac MRI. The array is compatible with multichannel transmission and provides a technological basis for future clinical assessment of parallel transmission techniques at 7.0T.
The concept of energy conversion into platform chemicals using bioelectrochemical systems (BES) has gained increasing attention in recent years, as the technology simultaneously provides an opportunity for sustainable chemical production and tackles the challenge of Power-to-X technologies. There are many approaches to realize the industrial scale of BES. One concept is to equip standard bioreactors with static electrodes. However, large installations resulted in a negative influence on various reactor parameters. In this study, we present a new single-chamber BES based on a stirred tank reactor in which the stirrer was replaced by a carbon fiber brush, performing the functions of the working electrode and the stirrer. The reactor is characterized in abiotic studies and electro-fermentations with Clostridium acetobutylicum. Compared to standard reactors an increase in butanol production of 20.14±3.66 % shows that the new BES can be efficiently used for bioelectrochemical processes.
New insights into the influence of pre-culture on robust solvent production of C. acetobutylicum
(2024)
Clostridia are known for their solvent production, especially the production of butanol. Concerning the projected depletion of fossil fuels, this is of great interest. The cultivation of clostridia is known to be challenging, and it is difficult to achieve reproducible results and robust processes. However, existing publications usually concentrate on the cultivation conditions of the main culture. In this paper, the influence of cryo-conservation and pre-culture on growth and solvent production in the resulting main cultivation are examined. A protocol was developed that leads to reproducible cultivations of Clostridium acetobutylicum. Detailed investigation of the cell conservation in cryo-cultures ensured reliable cell growth in the pre-culture. Moreover, a reason for the acid crash in the main culture was found, based on the cultivation conditions of the pre-culture. The critical parameter to avoid the acid crash and accomplish the shift to the solventogenesis of clostridia is the metabolic phase in which the cells of the pre-culture were at the time of inoculation of the main culture; this depends on the cultivation time of the pre-culture. Using cells from the exponential growth phase to inoculate the main culture leads to an acid crash. To achieve the solventogenic phase with butanol production, the inoculum should consist of older cells which are in the stationary growth phase. Considering these parameters, which affect the entire cultivation process, reproducible results and reliable solvent production are ensured.
Biomass from various types of organic waste was tested for possible use in hydrogen production. The composition consisted of lignified samples, green waste, and kitchen scraps such as fruit and vegetable peels and leftover food. For this purpose, the enzymatic pretreatment of organic waste with a combination of five different hydrolytic enzymes (cellulase, amylase, glucoamylase, pectinase and xylase) was investigated to determine its ability to produce hydrogen (H2) with the hydrolyzate produced here. In course, the anaerobic rod-shaped bacterium T. neapolitana was used for H2 production. First, the enzymes were investigated using different substrates in preliminary experiments. Subsequently, hydrolyses were carried out using different types of organic waste. In the hydrolysis carried out here for 48 h, an increase in glucose concentration of 481% was measured for waste loads containing starch, corresponding to a glucose concentration at the end of hydrolysis of 7.5 g·L−1. In the subsequent set fermentation in serum bottles, a H2 yield of 1.26 mmol H2 was obtained in the overhead space when Terrific Broth Medium with glucose and yeast extract (TBGY medium) was used. When hydrolyzed organic waste was used, even a H2 yield of 1.37 mmol could be achieved in the overhead space. In addition, a dedicated reactor system for the anaerobic fermentation of T. neapolitana to produce H2 was developed. The bioreactor developed here can ferment anaerobically with a very low loss of produced gas. Here, after 24 h, a hydrogen concentration of 83% could be measured in the overhead space.
Direct air capture (DAC) combined with subsequent storage (DACCS) is discussed as one promising carbon dioxide removal option. The aim of this paper is to analyse and comparatively classify the resource consumption (land use, renewable energy and water) and costs of possible DAC implementation pathways for Germany. The paths are based on a selected, existing climate neutrality scenario that requires the removal of 20 Mt of carbon dioxide (CO2) per year by DACCS from 2045. The analysis focuses on the so-called “low-temperature” DAC process, which might be more advantageous for Germany than the “high-temperature” one. In four case studies, we examine potential sites in northern, central and southern Germany, thereby using the most suitable renewable energies for electricity and heat generation. We show that the deployment of DAC results in large-scale land use and high energy needs. The land use in the range of 167–353 km2 results mainly from the area required for renewable energy generation. The total electrical energy demand of 14.4 TWh per year, of which 46% is needed to operate heat pumps to supply the heat demand of the DAC process, corresponds to around 1.4% of Germany's envisaged electricity demand in 2045. 20 Mt of water are provided yearly, corresponding to 40% of the city of Cologne‘s water demand (1.1 million inhabitants). The capture of CO2 (DAC) incurs levelised costs of 125–138 EUR per tonne of CO2, whereby the provision of the required energy via photovoltaics in southern Germany represents the lowest value of the four case studies. This does not include the costs associated with balancing its volatility. Taking into account transporting the CO2 via pipeline to the port of Wilhelmshaven, followed by transporting and sequestering the CO2 in geological storage sites in the Norwegian North Sea (DACCS), the levelised costs increase to 161–176 EUR/tCO2. Due to the longer transport distances from southern and central Germany, a northern German site using wind turbines would be the most favourable.
The successful implementation and continuous development of sustainable corporate-level solutions is a challenge. These are endeavours in which social, environmental, and financial aspects must be weighed against each other. They can prove difficult to handle and, in some cases, almost unrealistic. Concepts such as green controlling, IT, and manufacturing look promising and are constantly evolving. This paper aims to achieve a better understanding of the field of corporate sustainability (CS). It will evaluate the hypothesis by which Corporate Sustainability thrives, via being efficient, increasing the performance, and raising the value of the input of the enterprises to the resources used. In fact, Corporate Sustainability on the surface could seem to contradict the idea, which supports the understanding that it encourages the reduction of the heavy reliance on the use of natural resources, the overall environmental impact, and above all, their protection. To understand how the contradictory notion of CS came about, in this part of the paper, the emphasis is placed on providing useful insight to this regard. The first part of this paper summarizes various definitions, organizational theories, and measures used for CS and its derivatives like green controlling, IT, and manufacturing. Second, a case study is given that combines the aforementioned sustainability models. In addition to evaluating the hypothesis, the overarching objective of this paper is to demonstrate the use of green controlling, IT, and manufacturing in the corporate sector. Furthermore, this paper outlines the current challenges and possible directions for CS in the future.
This publication is intended to present the current state of research on the rebound effect. First, a systematic literature review is carried out to outline (current) scientific models and theories. Research Question 1 follows with a mathematical introduction of the rebound effect, which shows the interdependence of consumer behaviour, technological progress, and interwoven effects for both. Thereupon, the research field is analysed for gaps and limitations by a systematic literature review. To ensure quantitative and qualitative results, a review protocol is used that integrates two different stages and covers all relevant publications released between 2000 and 2019. Accordingly, 392 publications were identified that deal with the rebound effect. These papers were reviewed to obtain relevant information on the two research questions. The literature review shows that research on the rebound effect is not yet comprehensive and focuses mainly on the effect itself rather than solutions to avoid it. Research Question 2 finds that the main gap, and thus the limitations, is that not much research has been published on the actual avoidance of the rebound effect yet. This is a major limitation for practical application by decision-makers and politicians. Therefore, a theoretical analysis was carried out to identify potential theories and ideas to avoid the rebound effect. The most obvious idea to solve this problem is the theory of a Steady-State Economy (SSE), which has been described and reviewed.
Rapid development of virtual and data acquisition technology makes Digital Twin Technology (DT) one of the fundamental areas of research, while DT is one of the most promissory developments for the achievement of Industry 4.0. 48% percent of organisations implementing the Internet of Things are already using DT or plan to use DT in 2020. The global market for DT is expected to grow by 38 percent annually, reaching USD16 billion by 2023. In addition, the number of participating organisations using digital twins is expected to triple by 2022. DTs are characterised by the integration between physical and virtual spaces. The driving idea for DT is to develop, test and build our devices in a virtual environment. The objective of this paper is to study the impact of DT in the automotive industry on the new marketing logic. This paper outlines the current challenges and possible directions for the future DT in marketing. This paper will be helpful for managers in the industry to use the advantages and potentials of DT.
This paper uses a quantitative analysis to examine the interdependence and impact of resource rents on socio-economic development from 2002 to 2017. Nigeria and Norway have been chosen as reference countries due to their abundance of natural resources by similar economic performance, while the ranking in the Human Development Index differs dramatically. As the Human Development Index provides insight into a country’s cultural and socio-economic characteristics and development in addition to economic indicators, it allows a comparison of the two countries. The hypothesis presented and discussed in this paper was researched before. A qualitative research approach was used in the author’s master’s thesis “The Human Development Index (HDI) as a Reflection of Resource Abundance (using Nigeria and Norway as a case study)” in 2018. The management of scarce resources is an important aspect in the development of modern countries and those on the threshold of becoming industrialised nations. The effects of a mistaken resource management are not only of a purely economic nature but also of a social and socio-economic nature. In order to present a partial aspect of these dependencies and influences this paper uses a quantitative analysis to examine the interdependence and impact of resource rents on socio-economic development from 2002 to 2017. Nigeria and Norway have been chosen as reference countries due to their abundance of natural resources by similar economic performance, while the ranking in the Human Development Index differs significantly. As the Human Development Index provides insight into a country’s cultural and socio-economic characteristics and development in addition to economic indicators, it allows a comparison of the two countries. This paper found out in a holistic perspective that (not or poorly managed) resource wealth in itself has a negative impact on socio-economic development and significantly reduces the productivity of the citizens of a state. This is expressed in particular for the years 2002 till 2017 in a negative correlation of GDP per capita and HDI value with the share respectively the size of resources in the GDP of a country.
The following article deals with the basic principles of intercultural management and possible improvements in terms of cultural, ethnic and gender diversification. The results are exemplarily applied to a bank located in Germany. The aim of this paper is to find out to what extent intercultural management could improve the productivity of Relatos-Bank in dealing with foreign employees or employees with a different cultural background. To achieve this goal, the authors con-duct a literature research. The main sources of information are books, journal articles and internet sources. It becomes clear that especially the different perceptions of different generations have a potential for conflict, which can be counteracted by applying presented scientific models. Equalizing the salaries of female and male employees and equalizing the rights and distribution of power could also be the key to becoming an open-minded, dynamic and fair organization that is pre-pared for the rapidly changing environment in which it operates.
The presented paper gives an overview of the most important and most common theories and concepts from the economic field of organisational change and is also enriched with quantitative publication data, which underlines the relevance of the topic. In particular, the topic presented is interwoven in an interdisciplinary way with economic psychological models, which are underpinned within the models with content from leading scholars in the field. The pace of change in companies is accelerating, as is technological change in our society. Adaptations of the corporate structure, but also of management techniques and tasks, are therefore indispensable. This includes not only the right approaches to employee motivation, but also the correct use of intrinsic and extrinsic motivational factors. Based on the hypothesis put forward by the scientist and researcher Rollinson in his book “Organisational behaviour and analysis” that managers believe motivational resources are available at all times, socio-economic and economic psychological theories are contrasted here in order to critically examine this statement. In addition, a fictitious company was created as a model for this work in order to illustrate the effects of motivational deficits in practice. In this context, the theories presented are applied to concrete problems within the model and conclusions are drawn about their influence and applicability. This led to the conclusion that motivation is a very individual challenge for each employee, which requires adapted and personalised approaches. On the other hand, the recommendations for action for supervisors in the case of motivation deficits also cannot be answered in a blanket manner, but can only be solved with the help of professional, expert-supported processing due to the economic-psychological realities of motivation. Identifying, analysing and remedying individual employee motivation deficits is, according to the authors, a problem and a challenge of great importance, especially in the context of rapidly changing ecosystems in modern companies, as motivation also influences other factors such as individual productivity. The authors therefore conclude that good motivation through the individual and customised promotion and further training of employees is an important point for achieving important corporate goals in order to remain competitive on the one hand and to create a productive and pleasant working environment on the other.
Today’s society is undergoing a paradigm shift driven by the megatrend of sustainability. This undeniably affects all areas of Western life. This paper aims to find out how the luxury industry is dealing with this change and what adjustments are made by the companies. For this purpose, interviews were conducted with managers from the luxury industry, in which they were asked about specific measures taken by their companies as well as trends in the industry. In a subsequent evaluation, the trends in the luxury industry were summarized for the areas of ecological, social, and economic sustainability. It was found that the area of environmental sustainability is significantly more focused than the other sub-areas. Furthermore, the need for a customer survey to validate the industry-based measures was identified.
Unmanned Aerial Vehicles (UAV) constantly gain in versatility. However, more reliable path planning algorithms are required until full autonomous UAV operation is possible. This work investigates the algorithm 3DVFH* and analyses its dependency on its cost function weights in 2400 environments. The analysis shows that the 3DVFH* can find a suitable path in every environment. However, a particular type of environment requires a specific choice of cost function weights. For minimal failure, probability interdependencies between the weights of the cost function have to be considered. This dependency reduces the number of control parameters and simplifies the usage of the 3DVFH*. Weights for costs associated with vertical evasion (pitch cost) and vicinity to obstacles (obstacle cost) have the highest influence on the failure probability of the local path planner. Environments with mainly very tall buildings (like large American city centres) require a preference for horizontal avoidance manoeuvres (achieved with high pitch cost weights). In contrast, environments with medium-to-low buildings (like European city centres) benefit from vertical avoidance manoeuvres (achieved with low pitch cost weights). The cost of the vicinity to obstacles also plays an essential role and must be chosen adequately for the environment. Choosing these two weights ideal is sufficient to reduce the failure probability below 10%.
Lifting propellers are of increasing interest for Advanced Air Mobility. All propellers and rotors are initially twisted beams, showing significant extension–twist coupling and centrifugal twisting. Torsional deformations severely impact aerodynamic performance. This paper presents a novel approach to assess different reasons for torsional deformations. A reduced-order model runs large parameter sweeps with algebraic formulations and numerical solution procedures. Generic beams represent three different propeller types for General Aviation, Commercial Aviation, and Advanced Air Mobility. Simulations include solid and hollow cross-sections made of aluminum, steel, and carbon fiber-reinforced polymer. The investigation shows that centrifugal twisting moments depend on both the elastic and initial twist. The determination of the centrifugal twisting moment solely based on the initial twist suffers from errors exceeding 5% in some cases. The nonlinear parts of the torsional rigidity do not significantly impact the overall torsional rigidity for the investigated propeller types. The extension–twist coupling related to the initial and elastic twist in combination with tension forces significantly impacts the net cross-sectional torsional loads. While the increase in torsional stiffness due to initial twist contributes to the overall stiffness for General and Commercial Aviation propellers, its contribution to the lift propeller’s stiffness is limited. The paper closes with the presentation of approximations for each effect identified as significant. Numerical evaluations are necessary to determine each effect for inhomogeneous cross-sections made of anisotropic material.
Electronic cigarettes (e-cigarettes) have become popular worldwide with the market growing exponentially in some countries. The absence of product standards and safety regulations requires urgent development of analytical methodologies for the holistic control of the growing diversity of such products. An approach based on low-field nuclear magnetic resonance (LF-NMR) at 80 MHz is presented for the simultaneous determination of key parameters: carrier solvents (vegetable glycerine (VG), propylene glycol (PG) and water), total nicotine as well as free-base nicotine fraction. Moreover, qualitative and quantitative determination of fourteen weak organic acids deliberately added to enhance sensory characteristics of e-cigarettes was possible. In most cases these parameters can be rapidly and conveniently determined without using any sample manipulation such as dilution, extraction or derivatization steps. The method was applied for 37 authentic e-cigarettes samples. In particular, eight different organic acids with the content up to 56 mg/mL were detected. Due to its simplicity, the method can be used in routine regulatory control as well as to study release behaviour of nicotine and other e-cigarettes constituents in different products.