004 Datenverarbeitung; Informatik
Refine
Has Fulltext
- yes (203)
Year of publication
Document Type
- Journal article (78)
- Doctoral Thesis (75)
- Working Paper (37)
- Conference Proceeding (8)
- Master Thesis (3)
- Report (2)
Language
- English (183)
- German (19)
- Multiple languages (1)
Keywords
- Datennetz (14)
- Leistungsbewertung (13)
- virtual reality (12)
- Robotik (8)
- Mobiler Roboter (7)
- Autonomer Roboter (6)
- Komplexitätstheorie (5)
- Optimierung (5)
- P4 (5)
- Simulation (5)
- Theoretische Informatik (5)
- artificial intelligence (5)
- machine learning (5)
- Drahtloses Sensorsystem (4)
- Modellierung (4)
- Netzwerk (4)
- Optimization (4)
- Overlay-Netz (4)
- Routing (4)
- SDN (4)
- Verteiltes System (4)
- Algorithmus (3)
- Approximationsalgorithmus (3)
- Computer Vision (3)
- Computersimulation (3)
- Dienstgüte (3)
- Graph (3)
- Graphenzeichnen (3)
- Komplexität (3)
- Künstliche Intelligenz (3)
- Lokalisation (3)
- Mensch-Maschine-Schnittstelle (3)
- Netzwerkmanagement (3)
- Peer-to-Peer-Netz (3)
- Performance Evaluation (3)
- QoE (3)
- Quadrocopter (3)
- Quality of Experience (3)
- Rechnernetz (3)
- Ressourcenmanagement (3)
- Robotics (3)
- approximation algorithm (3)
- augmented reality (3)
- graph drawing (3)
- immersion (3)
- simulation (3)
- 5G (2)
- Algorithmische Geometrie (2)
- Ausfallsicheres System (2)
- Ausfallsicherheit (2)
- Benutzerschnittstelle (2)
- Crowdsourcing (2)
- Data Mining (2)
- Deep learning (2)
- Dot-Depth Problem (2)
- Drahtloses lokales Netz (2)
- Effizienter Algorithmus (2)
- Entscheidbarkeit (2)
- Entscheidungsfindung (2)
- Fernwartung (2)
- Future Internet (2)
- Human-Robot-Interaction (2)
- IEEE 802.11 (2)
- Internet of Things (2)
- IoT (2)
- Kleinsatellit (2)
- Kreuzung (2)
- Localization (2)
- MP-DCCP (2)
- Machine Learning (2)
- Maschinelles Lernen (2)
- Maschinelles Sehen (2)
- Mehragentensystem (2)
- Mensch-Maschine-System (2)
- Mensch-Roboter-Interaktion (2)
- Mixed Reality (2)
- Mustererkennung (2)
- NP-hardness (2)
- PROLOG <Programmiersprache> (2)
- Punktwolke (2)
- Quadrotor (2)
- Resilience (2)
- Resource Management (2)
- Satellit (2)
- Situation Awareness (2)
- Software Defined Networking (2)
- Software Engineering (2)
- Teleoperation (2)
- Theoretical Computer Science (2)
- User Interface (2)
- Verbotsmuster (2)
- XR (2)
- automation (2)
- connected mobility applications (2)
- crossing minimization (2)
- decidability (2)
- deep learning (2)
- dot-depth problem (2)
- education (2)
- educational tool (2)
- endliche Automaten (2)
- endoscopy (2)
- exposure (2)
- finite automata (2)
- fog computing (2)
- forbidden patterns (2)
- fully convolutional neural networks (2)
- games (2)
- gastroenterology (2)
- historical document analysis (2)
- human-computer interaction (2)
- knowledge representation (2)
- measurements (2)
- mobile networks (2)
- mobile robots (2)
- multipath (2)
- multipath scheduling (2)
- navigation (2)
- network calculus (2)
- neural networks (2)
- ontology (2)
- prediction (2)
- regular languages (2)
- reguläre Sprachen (2)
- satellite communication (2)
- scheduling (2)
- self-aware computing (2)
- virtual environments (2)
- 3D Laser Scanning (1)
- 3D Pointcloud (1)
- 3D Punktwolke (1)
- 3D Reconstruction (1)
- 3D Sensor (1)
- 3D Vision (1)
- 3D point cloud (1)
- 3D thermal mapping (1)
- 3D-Rekonstruktion (1)
- 3D-reconstruction methods (1)
- 3DTK toolkit (1)
- 4D-GIS (1)
- 4G Networks (1)
- 5G core network (1)
- 5G-ATSSS (1)
- 5GC (1)
- 6DOF Pose Estimation (1)
- 6G (1)
- ATSSSS (1)
- AVA (1)
- Abhängigskeitsgraph (1)
- Ablaufplanung (1)
- Add-on-Miss (1)
- Admission Control (1)
- Agent <Informatik> (1)
- Agent <Künstliche Intelligenz> (1)
- Agent-based Simulation (1)
- Agentbased System (1)
- Agenten-basierte Simulation (1)
- Angewandte Informatik (1)
- Annotation (1)
- Anwendung (1)
- Anwendungsfall (1)
- Approximation (1)
- Arterie (1)
- Artery (1)
- Aufsatzsammlung (1)
- Aufwandsanalyse (1)
- Automat <Automatentheorie> (1)
- Automata Theory (1)
- Automatentheorie (1)
- Automatisierte Prüfungskorrektur (1)
- Autonomer Agent (1)
- Autonomie (1)
- Autonomous Robot (1)
- Autonomous UAV (1)
- Autonomous multi-vehicle systems (1)
- Autorotation (1)
- Backbone-Netz (1)
- Background Knowledge (1)
- Balloon (1)
- Benutzerinteraktion (1)
- Berechenbarkeit (1)
- Berechnungskomplexität (1)
- Bernoulli stochastics (1)
- Bernoulli-Raum (1)
- Bernoullische Stochastik (1)
- Bernoullispace (1)
- Betriebssystem (1)
- Bewegungsablauf (1)
- Bewegungskompensation (1)
- Bewegungskoordination (1)
- Bewegungsplanung (1)
- Bildverarbeitung (1)
- Bit Parallelität (1)
- BitTorrent (1)
- Bodenstation (1)
- Boolean Grammar (1)
- Boolean equivalence (1)
- Boolean functions (1)
- Boolean hierarchy (1)
- Boolean isomorphism (1)
- Boolesche Funktionen (1)
- Boolesche Grammatik (1)
- Boolesche Hierarchie (1)
- Brüder Grimm Privatbibliothek (1)
- Business Intelligence (1)
- CASE (1)
- CLIP (1)
- Calibration (1)
- Call Graph (1)
- Chord (1)
- Clones (1)
- Cloud Gaming (1)
- Communication Networks (1)
- Complexity Theory (1)
- Compression (1)
- Computational Geometry (1)
- Computational complexity (1)
- Computerspiel (1)
- Computerunterstütztes Lernen (1)
- Containerization (1)
- Content Distribution (1)
- Convolutional Neural Network (1)
- Cost Analysis (1)
- Crowdsensing (1)
- CubeSat (1)
- DHT (1)
- DNA storage (1)
- Daedalus-Projekt (1)
- Databases (1)
- Datenbanken (1)
- Datenbasis (1)
- Datenkommunikationsnetz (1)
- Deep Georeferencing (1)
- Deep Learning (1)
- Dependency Graph (1)
- Design (1)
- Design and Development (1)
- Dezentrale Regelung (1)
- Diagnosesystem (1)
- Dichotomy (1)
- Digitalisierung (1)
- Dijkstra’s algorithm (1)
- Diskrete Simulation (1)
- Distributed Space Systems (1)
- Domänenspezifische Sprache (1)
- Dot-Depth-Hierarchie (1)
- Drahtloses vermaschtes Netz (1)
- Dreidimensionale Rekonstruktion (1)
- Dynamic Environments (1)
- Dynamic Memory Management (1)
- Dynamische Speicherverwaltung (1)
- EPM (1)
- Echtzeitsystem (1)
- Echzeit (1)
- Edge-MEC-Cloud (1)
- Edge-based Intelligence (1)
- Educational Measurement (I2.399) (1)
- Eingebettetes System (1)
- Elasticity tensor (1)
- Elastizitätstensor (1)
- Embedded Systems (1)
- Endnutzer (1)
- Endpoint Mobility (1)
- Energieeffizienz (1)
- Energy efficiency (1)
- Entscheidungsträger (1)
- Erfüllbarkeitsproblem (1)
- Erkennung handschriftlicher Artefakte (1)
- Erweiterte Realität (1)
- Ethik (1)
- Euclidean plane (1)
- Euklidische Ebene (1)
- Expert System (1)
- Expertensystem (1)
- FIFO caching strategies (1)
- Fachgespräch (1)
- Fahrsimulation (1)
- Fahrsimulator (1)
- Fairness (1)
- Fallstudie (1)
- Feature Based Registration (1)
- Feature-Matching (1)
- Fehlertoleranz (1)
- Feldprogrammierbare Architekturen (1)
- Fernsteuerung (1)
- Field programmable gate array (1)
- Field-programmable Gate Arrays (1)
- Flugkörper (1)
- Forces (1)
- Formale Sprache (1)
- Formation (1)
- Formation Flight (1)
- Formationsbewegung (1)
- Forschung (1)
- Frühdruck (1)
- Funkressourcenverwaltung (1)
- GNSS/INS integrated navigation (1)
- Gastroenterologische Endoskopie (1)
- Gay-Array-Bauelement (1)
- Generalisierung <Kartografie> (1)
- Generation Problem (1)
- Generierungsproblem (1)
- Genetic Optimization (1)
- Genetische Optimierung (1)
- Georeferenzierung (1)
- Gllobal self-localisation (1)
- Globale Selbstlokalisation (1)
- Grimm brothers personal library (1)
- Ground Station Networks (1)
- H.264 SVC (1)
- H.264/SVC (1)
- HMD (Head-Mounted Display) (1)
- HSPA (1)
- HTTP adaptive video streaming (1)
- Halbordnungen (1)
- Handschrift (1)
- Hardware (1)
- Herzkatheter (1)
- Herzkathetereingriff (1)
- Hierarchische Simulation (1)
- Hintergrundwissen (1)
- Historical Maps (1)
- Historische Karte (1)
- Historische Landkarten (1)
- Hospital (1)
- IEEE 802.11e (1)
- IEEE 802.15.4 (1)
- INS/LIDAR integrated navigation (1)
- IP (1)
- IT security (1)
- Image Aesthetic Assessment (1)
- Implementierung <Informatik> (1)
- Industrial internet (1)
- Industrie 4.0 (1)
- Inferenz <Künstliche Intelligenz> (1)
- Informatik (1)
- Information Extraction (1)
- Information Retrieval (1)
- Information-Retrieval-System (1)
- Instrument Control Toolbox (1)
- Intelligent Virtual Agents (1)
- InteractionSuitcase (1)
- Interaktion (1)
- Internet (1)
- Internet Protokoll (1)
- Invertierte Liste (1)
- Isomorphie (1)
- Itinerare (1)
- Itineraries (1)
- JCAS (1)
- Java <Programmiersprache> (1)
- Java Message Service (1)
- Kademlia (1)
- Kanalzugriff (1)
- Karte (1)
- Kartierung (1)
- Kathará (1)
- Kerneldensity estimation (1)
- Klassendiagramm (1)
- Klima (1)
- Knowledge Discovery (1)
- Knowledge-based Systems Engineering (1)
- Kombinatorik (1)
- Kommunikation (1)
- Kommunikationsnetze (1)
- Komplexitätsklasse (1)
- Komplexitätsklasse NP (1)
- Konvexe Zeichnungen (1)
- Konzeptsuche (1)
- Kooperierende mobile Roboter (1)
- Krankenhaus (1)
- Kreuzungsminimierung (1)
- Kurve (1)
- LFU (1)
- LRU (1)
- Landkartenbeschriftung (1)
- Landnutzungskartierung (1)
- Laser scanning (1)
- Lava (1)
- Learning (1)
- Lehre (1)
- Lernen (1)
- Lidar (1)
- Lightning (1)
- Link rate adaptation (1)
- Linkratenanpassung (1)
- Linux (1)
- LoRa (1)
- LoRaWAN (1)
- LoRaWan (1)
- Logic Programming (1)
- Logische Programmierung (1)
- Lunar Caves (1)
- Lunar Exploration (1)
- MAC (1)
- MTC (1)
- Mapping (1)
- Mars (1)
- Mathematische Modellierung (1)
- Mathematisches Modell (1)
- Medical Image Analysis (1)
- Medium <Physik> (1)
- Medizin (1)
- Mehrebenensimulation (1)
- Mehrfahrzeugsysteme (1)
- Mehrkriterielle Optimierung (1)
- Mehrpfadübertragung (1)
- Mehrschichtnetze (1)
- Mehrschichtsystem (1)
- Mensch-Maschine-Kommunikation (1)
- Mesh Networks (1)
- Mesh Netze (1)
- Methodologie (1)
- Middleware (1)
- Miniaturisierung (1)
- Minimally invasive vascular intervention (1)
- Missionsbetrieb (1)
- Mobile Roboter (1)
- Mobiles Internet (1)
- Mobilfunk (1)
- Modell (1)
- Modellbasierte Diagnose (1)
- Modellierungstechniken (1)
- Modelling (1)
- Modularität (1)
- Mond (1)
- Motion Planning (1)
- Multi-Agent-Simulation (1)
- Multi-Layer (1)
- Multi-Network Service (1)
- Multi-Netzwerk Dienste (1)
- Multi-Paradigm Programming (1)
- Multi-Paradigm Programming Framework (1)
- Multi-agent system (1)
- Multiagentensimulation (1)
- Multiagentensystem (1)
- Multimedia (1)
- Multipath Transmission (1)
- Multiple-Choice Examination (1)
- Multiple-Choice Prüfungen (1)
- NP (1)
- NP-Vollständigkeit (1)
- NP-complete sets (1)
- NP-hartes Problem (1)
- NP-schweres Problem (1)
- Network Emulator (1)
- Network Experiments (1)
- Network Management (1)
- Network Measurements (1)
- Network Virtualization (1)
- Netzplantechnik (1)
- Netzplanung (1)
- Netzvirtualisierung (1)
- Netzwerkplanung (1)
- Netzwerkvirtualisierung (1)
- Neuronales Netz (1)
- Next Generation Networks (1)
- Nichtholonome Fahrzeuge (1)
- Nichtlineare Regelung (1)
- Object Detection (1)
- Object-Oriented Programming (1)
- Objektorientierte Programmierung (1)
- Open Source (1)
- Operator (1)
- Optical Flow (1)
- Optimale Kontrolle (1)
- Optimierungsproblem (1)
- Overlay (1)
- Overlay Netzwerke (1)
- Overlay networks (1)
- Overlays (1)
- P4-INT (1)
- Panorama Images (1)
- Parameterkalibrierung (1)
- Partition <Mengenlehre> (1)
- Partitionen (1)
- Path Computation Element (1)
- Pattern Recognition (1)
- Peer-to-Peer (1)
- Performance Analysis (1)
- Performance Enhancing Proxies (1)
- Performance Management (1)
- Performance Modeling (1)
- Pfadberechnungselement (1)
- Picosatellite (1)
- Planare Graphen (1)
- Planausführung (1)
- Planung (1)
- Planungssystem (1)
- Poisson surface reconstruction (1)
- Polyeder (1)
- Polypektomie (1)
- Post's Classes (1)
- Postsche Klassen (1)
- Prediction (1)
- Process Optimization (1)
- Programmierbare logische Anordnung (1)
- Prozessoptimierung (1)
- Publish-Subscribe-System (1)
- QUIC (1)
- QoS (1)
- Quality of Experience (QoE) (1)
- Quality of Experience QoE (1)
- Quality of Service (1)
- Quality of Service (QoS) (1)
- Quality-of-Experience (1)
- Quality-of-Service (1)
- Quality-of-Service (QoS) (1)
- Quantor (1)
- RGB-D (1)
- RRM (1)
- Raumdaten (1)
- Real-Time Operating Systems (1)
- Real-time (1)
- Refactoring (1)
- Regelbasiertes System (1)
- Regelung (1)
- Registration (1)
- Registrierung (1)
- Reguläre Sprache (1)
- Rendezvous (1)
- Reproducibility (1)
- Resource and Performance Management (1)
- Ressourcen Management (1)
- Ressourcenallokation (1)
- Rettungsroboter (1)
- Robot (1)
- Roboter (1)
- Rule-based Systems (1)
- SBA (1)
- SDN/NVF (1)
- Scheduling (1)
- Search-and-Rescue (1)
- Selbstkalibrierung (1)
- Self-Evaluation Programs (I2.399.780) (1)
- Self-calibration (1)
- Semantic Web (1)
- Semantics (1)
- Semantik (1)
- Sensing-aaS (1)
- Sensor (1)
- Service Mobility (1)
- Sichtbarkeit (1)
- Similarity Measure (1)
- Simulator (1)
- Situationsbewusstsein (1)
- Skype (1)
- Small Satellites (1)
- Smart User Interaction (1)
- Social Web (1)
- Software (1)
- Software Performance Engineering (1)
- Software Performance Modeling (1)
- Source Code Visualization (1)
- Soziale Software (1)
- Spherical Robot (1)
- Standardisierung (1)
- Standortproblem (1)
- Sternfreie Sprache (1)
- Steuerung (1)
- Stiffness (1)
- Stochastik (1)
- Stochastikon (1)
- Strahlentherapie (1)
- Straubing-Th´erien-Hierarchie (1)
- Straßennetzwerk (1)
- Straßenverkehr (1)
- Structure-from-Motion (1)
- Strukturelle Komplexität (1)
- Subgroup Mining (1)
- Subgruppenentdeckung (1)
- Suchverfahren (1)
- System (1)
- Szenariogenerierung (1)
- TSN (1)
- TTL (1)
- TTL validation of data consistency (1)
- Teaching (1)
- Telematik (1)
- Terramechanics (1)
- Testbed (1)
- Theoretical computer science (1)
- Thermografie (1)
- Torque (1)
- Trainingssystem (1)
- Travelling-salesman-Problem (1)
- Tumor motion (1)
- Tumorbewegung (1)
- U-Bahnlinienplan (1)
- UI and Interaction Design (1)
- UML Klassendiagramm (1)
- UML class diagram (1)
- UMTS (1)
- URL (1)
- URLLC (1)
- Underwater Mapping (1)
- Underwater Scanning (1)
- Unmanned Aerial Vehicle (1)
- Unstetige Regelung (1)
- Usability (1)
- Use case (1)
- User Behavior (1)
- User Participation (1)
- VNF (1)
- VPN (1)
- Venus (1)
- Veranstaltung (1)
- Verbotenes Muster (1)
- Verbände (1)
- Verkehrslenkung (1)
- Verteilung von Inhalten (1)
- Video Quality Monitoring (1)
- Video Streaming (1)
- Videoübertragung (1)
- Virtualisierung (1)
- Virtuelles Netzwerk (1)
- Visibility (1)
- Visual Tracking (1)
- Visualisierung (1)
- Visualization (1)
- Visualized Kathará (1)
- Voice-over-IP (VoIP) (1)
- Volltextsuche (1)
- Vorhersage (1)
- WLAN (1)
- Warteschlangentheorie (1)
- Werkstattdiagnose (1)
- WhatsApp (1)
- Wheel (1)
- Winkel (1)
- Wire relaxation (1)
- Wireless LAN (1)
- Wireless Sensor/Actuator Systems (1)
- Wissensbasiertes System (1)
- Wissensendeckung (1)
- Wissensrepräsentation (1)
- Worterweiterungen (1)
- XR-artificial intelligence combination (1)
- XR-artificial intelligence continuum (1)
- YouTube (1)
- Zeichnen von Graphen (1)
- Zeitdiskretes System (1)
- Zugangskontrolle (1)
- Zählprobleme (1)
- abgeschlossene Klassen (1)
- acrophobia (1)
- adaptation models (1)
- administrative boundary (1)
- admission control (1)
- adult learning (1)
- aerodynamics (1)
- aerospace (1)
- aftermarket diagnostic (1)
- agent-based models (1)
- agents (1)
- agile Prozesse (1)
- agile processes (1)
- angular schematization (1)
- annotation (1)
- anomaly detection (1)
- anomaly prediction (1)
- ant-colony optimization (1)
- anthropomorphism (1)
- anxiety (1)
- application design (1)
- approximation algorithms (1)
- arithmetic calculations (1)
- automatic Layout (1)
- automatisches Layout (1)
- autonomic orchestration (1)
- autonomous (1)
- autonomous UAV (1)
- autorotation (1)
- availability (1)
- avatar embodiment (1)
- avatars (1)
- background knowledge (1)
- baseline detection (1)
- behavior perception (1)
- binary tanglegram (1)
- biosignals (1)
- bit-parallel (1)
- boundary labeling (1)
- building (1)
- camera orientation (1)
- car-like robots (1)
- carbon (1)
- case study (1)
- certifying algorithm (1)
- chain cover (1)
- channel management (1)
- climate (1)
- co-authorships (1)
- co-inventorships (1)
- coherence (1)
- collaboration (1)
- collision (1)
- communication models (1)
- communication networks (1)
- competitive location (1)
- complexity (1)
- computational complexity (1)
- computer performance evaluation (1)
- computergestützte Softwaretechnik (1)
- concept search (1)
- congruence (1)
- constrained forest (1)
- contact representation (1)
- container virtualization (1)
- content-based image retrieval (1)
- continuous-time SLAM (1)
- convex bipartite graph (1)
- convolutional neural network (1)
- cost-sensitive learning (1)
- counting problems (1)
- crowdsensing (1)
- crowdsourced QoE measurements (1)
- crowdsourced measurements (1)
- crowdsourced network measurements (1)
- cultural and media studies (1)
- culturally aware (1)
- curves (1)
- d3web.Train (1)
- data mining (1)
- data plane programming (1)
- data structure (1)
- data warehouse (1)
- database (1)
- dataplane programming (1)
- decision support system (1)
- decision-making (1)
- decission finding (1)
- decoding error rate (1)
- deep metric learning (1)
- definite clause grammars (1)
- deformation-based method (1)
- delay QoS exponent (1)
- delay bound violation probability (1)
- delay constrained (1)
- descent (1)
- design (1)
- design cycle (1)
- detection time simulation (1)
- dial a ride (1)
- digital twin (1)
- dimensions of proximity (1)
- discrete-time analysis (1)
- disjoint multi-paths (1)
- distributed control (1)
- docker (1)
- driving simulation (1)
- dynamic flow migration (1)
- dynamic programming (1)
- dynamische Umgebungen (1)
- eHealth (1)
- early printed books (1)
- edge labeled graphs (1)
- effective Bandwidth (1)
- efficient algorithm (1)
- electronic health records (1)
- elevated plus-maze (1)
- embedding techniques (1)
- emotions (1)
- emulation (1)
- encryption (1)
- end user (1)
- endurance (1)
- energy efficiency (1)
- event detection (1)
- exercise intensity (1)
- experience (1)
- experimental evaluation (1)
- extended reality (XR) (1)
- failure prediction (1)
- fast reroute (1)
- fault detection (1)
- feature matching (1)
- feature-matching (1)
- federated learning (1)
- few-shot learning (1)
- field-programmable architectures (1)
- field-programmable gate arrays (1)
- fixed-parameter tractability (1)
- food quality (1)
- foreign language learning and teaching (1)
- formation driving (1)
- formation flight (1)
- fruit temperature (1)
- full-text search (1)
- future Internet architecture (1)
- future energy grid exploration (1)
- game mechanics (1)
- gamification (1)
- genetic algorithm (1)
- global IPX network (1)
- graph (1)
- graph algorithm (1)
- graph decomposition (1)
- graphs (1)
- group-based communication (1)
- handwriting (1)
- handwritten artefact recognition (1)
- haptic data (1)
- hardness (1)
- hardware-in-the-loop simulation (1)
- hardware-in-the-loop streaming system (1)
- hierarchy (1)
- historical images (1)
- hit ratio analysis and simulation (1)
- hospital data (1)
- human body weight (1)
- human computer interaction (HCI) (1)
- human-artificial intelligence interaction (1)
- human-artificial intelligence interface (1)
- human-centered design (1)
- human-centered, human-robot (1)
- human–computer interaction (1)
- hybrid Diagnostic (1)
- hybrid access (1)
- hybride Diagnose (1)
- illusion of self-motion (1)
- image classification (1)
- image processing (1)
- imbalanced regression (1)
- immersive classroom (1)
- immersive classroom management (1)
- immersive learning technologies (1)
- immersive technologies (1)
- implicit association test (1)
- independent crossing (1)
- induced matching (1)
- informal education (1)
- information extraction (1)
- information systems and information technology (1)
- intelligent transportation systems (1)
- intelligent vehicles (1)
- intelligent virtual agents (1)
- intelligent voice assistant (1)
- intelligente Applikationen (1)
- interactive authoring system (1)
- intercultural learning and teaching (1)
- interdisciplinary education (1)
- internet protocol (1)
- internet traffic (1)
- invasive vascular interventions (1)
- iowa gambling task (1)
- key-insight extraction (1)
- kinect (1)
- labeling (1)
- land-cover area (1)
- landing (1)
- language-image pre-training (1)
- latency (1)
- lattices (1)
- layout recognition (1)
- learning environments (1)
- least cost (1)
- light-gated proteins (1)
- load balancing (1)
- local energy system (1)
- locomotion (1)
- logic programming (1)
- logistics (1)
- long-term analysis (1)
- map projections (1)
- mapping (1)
- mathematical model (1)
- media analysis (1)
- medical records (1)
- medieval manuscripts (1)
- meditation (1)
- metro map (1)
- mindfulness (1)
- misconceptions (1)
- mission operation (1)
- mixed reality (1)
- mixed-cultural (1)
- mixed-cultural settings (1)
- mobile instant messaging (1)
- mobile messaging application (1)
- mobile streaming (1)
- model following (1)
- model output statistics (1)
- model predictive control (1)
- model-base diagnosis (1)
- model-based diagnosis (1)
- modeling techniques (1)
- monotone drawing (1)
- morphing (1)
- multi-vehicle formations (1)
- multi-vehicle rendezvous (1)
- multimodal fusion (1)
- multimodal interface (1)
- multimodal learning (1)
- multipath communication (1)
- multipath packet scheduling (1)
- multiple myeloma (1)
- multirotors (1)
- multiscale encoder (1)
- n-Gramm (1)
- n-gram (1)
- nano-satellite (1)
- nanocellulose (1)
- natural interfaces (1)
- natural language processing (1)
- natural language processing · · · (1)
- natural user interfaces (1)
- network (1)
- network design (1)
- network planning (1)
- network softwarization (1)
- network upgrade (1)
- network virtualization (1)
- networked robotics (1)
- networking (1)
- networks (1)
- neume notation (1)
- neural architecture (1)
- non-native accent (1)
- non-terrestrial networks (1)
- nonholonomic vehicles (1)
- object detection (1)
- octree (1)
- open source (1)
- optical music recognition (1)
- optimization (1)
- orchestration (1)
- overprovisioning (1)
- packet reception method (1)
- partitions (1)
- passage of time (1)
- passive haptic feedback (1)
- path computation (1)
- pattern perception (1)
- perception (1)
- performance (1)
- performance analysis (1)
- performance evaluation (1)
- performance monitoring (1)
- performance prediction (1)
- place-illusion (1)
- plain orchestrating service (1)
- plan execution (1)
- plausibility (1)
- plausibility-illusion (1)
- point cloud (1)
- point cloud compression (1)
- point-to-plane measure (1)
- point-to-point measure (1)
- pollution (1)
- pos (1)
- posets (1)
- positioning (1)
- precision horticulture (1)
- precision training (1)
- presence (1)
- private chat groups (1)
- procedural content generation (1)
- procedural fusion methods (1)
- process model (1)
- prompt engineering (1)
- protein chip (1)
- psychomotor training (1)
- psychophyisology (1)
- public speaking (1)
- q-Gramm (1)
- q-gram (1)
- quadcopter (1)
- quadcopters (1)
- quality assurance (1)
- quality evaluation (1)
- quality of experience (1)
- quality of experience prediction (1)
- radio resource management (1)
- radiology (1)
- ransomware (1)
- real world evidence (1)
- real-world application (1)
- realism (1)
- receding horizon control (1)
- recommender system (1)
- reconfiguration (1)
- regelbasierte Nachbearbeitung (1)
- reload cost (1)
- remote control (1)
- research methods (1)
- resilience (1)
- rich vehicle routing problem (1)
- right angle crossing (1)
- road network (1)
- robotics (1)
- robustness (1)
- rotorcraft (1)
- rotors (1)
- routing (1)
- rule based post processing (1)
- sample weighting (1)
- satisfiability problems (1)
- scalability (1)
- scalability evaluation (1)
- scalable quadcopter (1)
- scenario creation (1)
- science, technology and society (1)
- secure group communication (1)
- segmentation (1)
- self-adaptive (1)
- self-adaptive systems (1)
- self-assembly (1)
- self-aware computing systems (1)
- self-managing systems (1)
- semantic fusion (1)
- semantic understanding (1)
- semantic web (1)
- semantical aesthetic (1)
- semantische Ästhetik (1)
- sensor (1)
- sensor devices (1)
- sensor fusion (1)
- sensor network (1)
- sentinel (1)
- serious games (1)
- service-curve estimation (1)
- sesnsors (1)
- short block-length (1)
- shortest path routing (1)
- signaling traffic (1)
- simulation system (1)
- simultaneous embedding (1)
- single-electron transistors (1)
- skalierbare Diagnose (1)
- sketching (1)
- slam (1)
- smart meter data utilization (1)
- smart speaker (1)
- smooth orthogonal drawing (1)
- snow shoveling (1)
- social VR (1)
- social interaction (1)
- social relationship (1)
- social robot (1)
- social robotics (1)
- social role (1)
- socially interactive agents (1)
- software defined network (1)
- spanning tree (1)
- spatial presence (1)
- standardization (1)
- state management (1)
- statistical validity (1)
- statistics and numerical data (1)
- stereotypes (1)
- stochastic thinking (1)
- stochastisches Denken (1)
- stroke (1)
- structural complexity (1)
- student simulation (1)
- stylus (1)
- sunburn (1)
- supervised learning (1)
- surface model (1)
- survey (1)
- sustainability (1)
- switching navigation (1)
- system (1)
- systematic literature review (1)
- systematic review (1)
- table extraction (1)
- table understanding (1)
- taxonomy (1)
- teacher education (1)
- technology-supported learning (1)
- telematics (1)
- text line detection (1)
- text supervision (1)
- theory (1)
- therapeutic application (1)
- thermal camera (1)
- thermal point cloud (1)
- time calibration (1)
- time perception (1)
- timestamping method (1)
- tools (1)
- topology (1)
- training systems (1)
- trait anxiety (1)
- trajectory planning (1)
- transformer (1)
- translational neuroscience (1)
- transport microenvironments (1)
- transport protocols (1)
- transportation (1)
- tree (1)
- unmanned aerial vehicle (1)
- unmanned aerial vehicles (1)
- usability evaluation (1)
- use cases (1)
- user experience (1)
- user interaction (1)
- user study (1)
- user-generated content (1)
- v (1)
- vection (1)
- vehicle dynamics (1)
- vehicular navigation (1)
- verbal behaviour (1)
- vernetzte Roboter (1)
- virtual agent (1)
- virtual agent interaction (1)
- virtual humans (1)
- virtual queue (1)
- virtual reality training (1)
- virtual stimuli (1)
- virtual tunnel (1)
- virtual-reality-continuum (1)
- vom Nutzer erfahrene Dienstgüte QoE (1)
- voting location (1)
- waypoint parameter (1)
- wearable (1)
- wheel (1)
- wireless network (1)
- word clouds (1)
- word extensions (1)
- zooming (1)
- zukünftige Kommunikationsnetze (1)
- zukünftiges Internet (1)
- Ähnlichkeitsmaß (1)
Institute
- Institut für Informatik (203) (remove)
Schriftenreihe
Sonstige beteiligte Institutionen
In the present day, unmanned aerial vehicles become seemingly more popular every year, but, without regulation of the increasing number of these vehicles, the air space could become chaotic and uncontrollable. In this work, a framework is proposed to combine self-aware computing with multirotor formations to address this problem. The self-awareness is envisioned to improve the dynamic behavior of multirotors. The formation scheme that is implemented is called platooning, which arranges vehicles in a string behind the lead vehicle and is proposed to bring order into chaotic air space. Since multirotors define a general category of unmanned aerial vehicles, the focus of this thesis are quadcopters, platforms with four rotors. A modification for the LRA-M self-awareness loop is proposed and named Platooning Awareness. The implemented framework is able to offer two flight modes that enable waypoint following and the self-awareness module to find a path through scenarios, where obstacles are present on the way, onto a goal position. The evaluation of this work shows that the proposed framework is able to use self-awareness to learn about its environment, avoid obstacles, and can successfully move a platoon of drones through multiple scenarios.
Towards LoRaWAN without data loss: studying the performance of different channel access approaches
(2022)
The Long Range Wide Area Network (LoRaWAN) is one of the fastest growing Internet of Things (IoT) access protocols. It operates in the license free 868 MHz band and gives everyone the possibility to create their own small sensor networks. The drawback of this technology is often unscheduled or random channel access, which leads to message collisions and potential data loss. For that reason, recent literature studies alternative approaches for LoRaWAN channel access. In this work, state-of-the-art random channel access is compared with alternative approaches from the literature by means of collision probability. Furthermore, a time scheduled channel access methodology is presented to completely avoid collisions in LoRaWAN. For this approach, an exhaustive simulation study was conducted and the performance was evaluated with random access cross-traffic. In a general theoretical analysis the limits of the time scheduled approach are discussed to comply with duty cycle regulations in LoRaWAN.
In recent years, satellite communication has been expanding its field of application in the world of computer networks. This paper aims to provide an overview of how a typical scenario involving 5G Non-Terrestrial Networks (NTNs) for vehicle to everything (V2X) applications is characterized. In particular, a first implementation of a system that integrates them together will be described. Such a framework will later be used to evaluate the performance of applications such as Vehicle Monitoring (VM), Remote Driving (RD), Voice Over IP (VoIP), and others. Different configuration scenarios such as Low Earth Orbit and Geostationary Orbit will be considered.
Parametric weighted finite automata (PWFA) are a multi-dimensional generalization of weighted finite automata. The expressiveness of PWFA contains the expressiveness of weighted finite automata as well as the expressiveness of affine iterated function system. The thesis discusses theory and applications of PWFA. The properties of PWFA definable sets are studied and it is shown that some fractal generator systems can be simulated using PWFA and that various real and complex functions can be represented by PWFA. Furthermore, the decoding of PWFA and the interpretation of PWFA definable sets is discussed.
Psycho-pathological conditions, such as depression or schizophrenia, are often accompanied by a distorted perception of time. People suffering from this conditions often report that the passage of time slows down considerably and that they are “stuck in time.” Virtual Reality (VR) could potentially help to diagnose and maybe treat such mental conditions. However, the conditions in which a VR simulation could correctly diagnose a time perception deviation are still unknown. In this paper, we present an experiment investigating the difference in time experience with and without a virtual body in VR, also known as avatar. The process of substituting a person’s body with a virtual body is called avatar embodiment. Numerous studies demonstrated interesting perceptual, emotional, behavioral, and psychological effects caused by avatar embodiment. However, the relations between time perception and avatar embodiment are still unclear. Whether or not the presence or absence of an avatar is already influencing time perception is still open to question. Therefore, we conducted a between-subjects design with and without avatar embodiment as well as a real condition (avatar vs. no-avatar vs. real). A group of 105 healthy subjects had to wait for seven and a half minutes in a room without any distractors (e.g., no window, magazine, people, decoration) or time indicators (e.g., clocks, sunlight). The virtual environment replicates the real physical environment. Participants were unaware that they will be asked to estimate their waiting time duration as well as describing their experience of the passage of time at a later stage. Our main finding shows that the presence of an avatar is leading to a significantly faster perceived passage of time. It seems to be promising to integrate avatar embodiment in future VR time-based therapy applications as they potentially could modulate a user’s perception of the passage of time. We also found no significant difference in time perception between the real and the VR conditions (avatar, no-avatar), but further research is needed to better understand this outcome.
Despite the fact that mixed-cultural backgrounds become of increasing importance in our daily life, the representation of multiple cultural backgrounds in one entity is still rare in socially interactive agents (SIAs). This paper’s contribution is twofold. First, it provides a survey of research on mixed-cultured SIAs. Second, it presents a study investigating how mixed-cultural speech (in this case, non-native accent) influences how a virtual robot is perceived in terms of personality, warmth, competence and credibility. Participants with English or German respectively as their first language watched a video of a virtual robot speaking in either standard English or German-accented English. It was expected that the German-accented speech would be rated more positively by native German participants as well as elicit the German stereotypes credibility and conscientiousness for both German and English participants. Contrary to the expectations, German participants rated the virtual robot lower in terms of competence and credibility when it spoke with a German accent, whereas English participants perceived the virtual robot with a German accent as more credible compared to the version without an accent. Both the native English and native German listeners classified the virtual robot with a German accent as significantly more neurotic than the virtual robot speaking standard English. This work shows that by solely implementing a non-native accent in a virtual robot, stereotypes are partly transferred. It also shows that the implementation of a non-native accent leads to differences in the perception of the virtual robot.
The thesis looks at the question asking for the computability of the dot-depth of star-free regular languages. Here one has to determine for a given star-free regular language the minimal number of alternations between concatenation on one hand, and intersection, union, complement on the other hand. This question was first raised in 1971 (Brzozowski/Cohen) and besides the extended star-heights problem usually refered to as one of the most difficult open questions on regular languages. The dot-depth problem can be captured formally by hierarchies of classes of star-free regular languages B(0), B(1/2), B(1), B(3/2),... and L(0), L(1/2), L(1), L(3/2),.... which are defined via alternating the closure under concatenation and Boolean operations, beginning with single alphabet letters. Now the question of dot-depth is the question whether these hierarchy classes have decidable membership problems. The thesis makes progress on this question using the so-called forbidden pattern approach: Classes of regular languages are characterized in terms of patterns in finite automata (subgraphs in the transition graph) that are not allowed. Such a characterization immediately implies the decidability of the respective class, since the absence of a certain pattern in a given automaton can be effectively verified. Before this work, the decidability of B(0), B(1/2), B(1) and L(0), L(1/2), L(1), L(3/2) were known. Here a detailed study of these classes with help of forbidden patterns is given which leads to new insights into their inner structure. Furthermore, the decidability of B(3/2) is proven. Based on these results a theory of pattern iteration is developed which leads to the introduction of two new hierarchies of star-free regular languages. These hierarchies are decidable on one hand, on the other hand they are in close connection to the classes B(n) and L(n). It remains an open question here whether they may in fact coincide. Some evidence is given in favour of this conjecture which opens a new way to attack the dot-depth problem. Moreover, it is shown that the class L(5/2) is decidable in the restricted case of a two-letter alphabet.
This technical report introduces the Descartes Modeling Language (DML), a new architecture-level modeling language for modeling Quality-of-Service (QoS) and resource management related aspects of modern dynamic IT systems, infrastructures and services. DML is designed to serve as a basis for self-aware resource management during operation ensuring that system QoS requirements are continuously satisfied while infrastructure resources are utilized as efficiently as possible.
This work deals with teams in teleoperation scenarios, where one human team partner (supervisor) guides and controls multiple remote entities (either robotic or human) and coordinates their tasks. Such a team needs an appropriate infrastructure for sharing information and commands. The robots need to have a level of autonomy, which matches the assigned task. The humans in the team have to be provided with autonomous support, e.g. for information integration. Design and capabilities of the human-robot interfaces will strongly influence the performance of the team as well as the subjective feeling of the human team partners. Here, it is important to elaborate the information demand as well as how information is presented. Such human-robot systems need to allow the supervisor to gain an understanding of what is going on in the remote environment (situation awareness) by providing the necessary information. This includes achieving fast assessment of the robot´s or remote human´s state. Processing, integration and organization of data as well as suitable autonomous functions support decision making and task allocation and help to decrease the workload in this multi-entity teleoperation task. Interaction between humans and robots is improved by a common world model and a responsive system and robots. The remote human profits from a simplified user interface providing exactly the information needed for the actual task at hand. The topic of this thesis is the investigation of such teleoperation interfaces in human-robot teams, especially for high-risk, time-critical, and dangerous tasks. The aim is to provide a suitable human-robot team structure as well as analyze the demands on the user interfaces. On one side, it will be looked on the theoretical background (model, interactions, and information demand). On the other side, real implementations for system, robots, and user interfaces are presented and evaluated as testbeds for the claimed requirements. Rescue operations, more precisely fire-fighting, was chosen as an exemplary application scenario for this work. The challenges in such scenarios are high (highly dynamic environments, high risk, time criticality etc.) and it can be expected that results can be transferred to other applications, which have less strict requirements. The present work contributes to the introduction of human-robot teams in task-oriented scenarios, such as working in high risk domains, e.g. fire-fighting. It covers the theoretical background of the required system, the analysis of related human factors concepts, as well as discussions on implementation. An emphasis is placed on user interfaces, their design, requirements and user testing, as well as on the used techniques (three-dimensional sensor data representation, mixed reality, and user interface design guidelines). Further, the potential integration of 3D sensor data as well as the visualization on stereo visualization systems is introduced.
In the last decades, the classical Vehicle Routing Problem (VRP), i.e., assigning a set of orders to vehicles and planning their routes has been intensively researched. As only the assignment of order to vehicles and their routes is already an NP-complete problem, the application of these algorithms in practice often fails to take into account the constraints and restrictions that apply in real-world applications, the so called rich VRP (rVRP) and are limited to single aspects. In this work, we incorporate the main relevant real-world constraints and requirements. We propose a two-stage strategy and a Timeline algorithm for time windows and pause times, and apply a Genetic Algorithm (GA) and Ant Colony Optimization (ACO) individually to the problem to find optimal solutions. Our evaluation of eight different problem instances against four state-of-the-art algorithms shows that our approach handles all given constraints in a reasonable time.
This thesis is devoted to the study of computational complexity theory, a branch of theoretical computer science. Computational complexity theory investigates the inherent difficulty in designing efficient algorithms for computational problems. By doing so, it analyses the scalability of computational problems and algorithms and places practical limits on what computers can actually accomplish. Computational problems are categorised into complexity classes. Among the most important complexity classes are the class NP and the subclass of NP-complete problems, which comprises many important optimisation problems in the field of operations research. Moreover, with the P-NP-problem, the class NP represents the most important unsolved question in computer science. The first part of this thesis is devoted to the study of NP-complete-, and more generally, NP-hard problems. It aims at improving our understanding of this important complexity class by systematically studying how altering NP-hard sets affects their NP-hardness. This research is related to longstanding open questions concerning the complexity of unions of disjoint NP-complete sets, and the existence of sparse NP-hard sets. The second part of the thesis is also dedicated to complexity classes but takes a different perspective: In a sense, after investigating the interior of complexity classes in the first part, the focus shifts to the description of complexity classes and thereby to the exterior in the second part. It deals with the description of complexity classes through leaf languages, a uniform framework which allows us to characterise a great variety of important complexity classes. The known concepts are complemented by a new leaf-language model. To a certain extent, this new approach combines the advantages of the known models. The presented results give evidence that the connection between the theory of formal languages and computational complexity theory might be closer than formerly known.
The increased occurrence of Software-Defined-Networking (SDN) not only improves the dynamics and maintenance of network architectures, but also opens up new use cases and application possibilities. Based on these observations, we propose a new network topology consisting of a star and a ring topology. This hybrid topology will be called wheel topology in this paper. We have considered the static characteristics of the wheel topology and compare them with known other topologies.
Even today, the automatic digitisation of scanned documents in general, but especially the automatic optical music recognition (OMR) of historical manuscripts, still remains an enormous challenge, since both handwritten musical symbols and text have to be identified. This paper focuses on the Medieval so-called square notation developed in the 11th–12th century, which is already composed of staff lines, staves, clefs, accidentals, and neumes that are roughly spoken connected single notes. The aim is to develop an algorithm that captures both the neumes, and in particular its melody, which can be used to reconstruct the original writing. Our pipeline is similar to the standard OMR approach and comprises a novel staff line and symbol detection algorithm based on deep Fully Convolutional Networks (FCN), which perform pixel-based predictions for either staff lines or symbols and their respective types. Then, the staff line detection combines the extracted lines to staves and yields an F\(_1\) -score of over 99% for both detecting lines and complete staves. For the music symbol detection, we choose a novel approach that skips the step to identify neumes and instead directly predicts note components (NCs) and their respective affiliation to a neume. Furthermore, the algorithm detects clefs and accidentals. Our algorithm predicts the symbol sequence of a staff with a diplomatic symbol accuracy rate (dSAR) of about 87%, which includes symbol type and location. If only the NCs without their respective connection to a neume, all clefs and accidentals are of interest, the algorithm reaches an harmonic symbol accuracy rate (hSAR) of approximately 90%. In general, the algorithm recognises a symbol in the manuscript with an F\(_1\) -score of over 96%.
Plenty of theories, models, measures, and investigations target the understanding of virtual presence, i.e., the sense of presence in immersive Virtual Reality (VR). Other varieties of the so-called eXtended Realities (XR), e.g., Augmented and Mixed Reality (AR and MR) incorporate immersive features to a lesser degree and continuously combine spatial cues from the real physical space and the simulated virtual space. This blurred separation questions the applicability of the accumulated knowledge about the similarities of virtual presence and presence occurring in other varieties of XR, and corresponding outcomes. The present work bridges this gap by analyzing the construct of presence in mixed realities (MR). To achieve this, the following presents (1) a short review of definitions, dimensions, and measurements of presence in VR, and (2) the state of the art views on MR. Additionally, we (3) derived a working definition of MR, extending the Milgram continuum. This definition is based on entities reaching from real to virtual manifestations at one time point. Entities possess different degrees of referential power, determining the selection of the frame of reference. Furthermore, we (4) identified three research desiderata, including research questions about the frame of reference, the corresponding dimension of transportation, and the dimension of realism in MR. Mainly the relationship between the main aspects of virtual presence of immersive VR, i.e., the place-illusion, and the plausibility-illusion, and of the referential power of MR entities are discussed regarding the concept, measures, and design of presence in MR. Finally, (5) we suggested an experimental setup to reveal the research heuristic behind experiments investigating presence in MR. The present work contributes to the theories and the meaning of and approaches to simulate and measure presence in MR. We hypothesize that research about essential underlying factors determining user experience (UX) in MR simulations and experiences is still in its infancy and hopes this article provides an encouraging starting point to tackle related questions.
This thesis deals with the management and analysis of source code, which is represented in XML. Using the elementary methods of the XML repository, the XML source code representation is accessed, changed, updated, and saved. We reason about the source code, refactor source code and we visualize dependency graphs for call analysis. The visualized dependencies between files, modules, or packages are used to structure the source code in order to get a system, which is easily to comprehend, to modify and to complete. Sophisticated methods have been developed to slice the source code in order to obtain a working package of a large system, containing only a specific functionality. The basic methods, on which the visualizations and analyses are built on can be changed like changing a plug-in. The visualization methods can be reused in order to handle arbitrary source code representations, e.g., JAML, PHPML, PROLOGML. Dependencies of other context can be visualized, too, e.g., ER diagrams, or website references. The tool SCAV supports source code visualization and analyzing methods.
The rating of perceived exertion (RPE) is a subjective load marker and may assist in individualizing training prescription, particularly by adjusting running intensity. Unfortunately, RPE has shortcomings (e.g., underreporting) and cannot be monitored continuously and automatically throughout a training sessions. In this pilot study, we aimed to predict two classes of RPE (≤15 “Somewhat hard to hard” on Borg’s 6–20 scale vs. RPE >15 in runners by analyzing data recorded by a commercially-available smartwatch with machine learning algorithms. Twelve trained and untrained runners performed long-continuous runs at a constant self-selected pace to volitional exhaustion. Untrained runners reported their RPE each kilometer, whereas trained runners reported every five kilometers. The kinetics of heart rate, step cadence, and running velocity were recorded continuously ( 1 Hz ) with a commercially-available smartwatch (Polar V800). We trained different machine learning algorithms to estimate the two classes of RPE based on the time series sensor data derived from the smartwatch. Predictions were analyzed in different settings: accuracy overall and per runner type; i.e., accuracy for trained and untrained runners independently. We achieved top accuracies of 84.8 % for the whole dataset, 81.8 % for the trained runners, and 86.1 % for the untrained runners. We predict two classes of RPE with high accuracy using machine learning and smartwatch data. This approach might aid in individualizing training prescriptions.
Object six Degrees of Freedom (6DOF) pose estimation is a fundamental problem in many practical robotic applications, where the target or an obstacle with a simple or complex shape can move fast in cluttered environments. In this thesis, a 6DOF pose estimation algorithm is developed based on the fused data from a time-of-flight camera and a color camera. The algorithm is divided into two stages, an annealed particle filter based coarse pose estimation stage and a gradient decent based accurate pose optimization stage. In the first stage, each particle is evaluated with sparse representation. In this stage, the large inter-frame motion of the target can be well handled. In the second stage, the range data based conventional Iterative Closest Point is extended by incorporating the target appearance information and used for calculating the accurate pose by refining the coarse estimate from the first stage. For dealing with significant illumination variations during the tracking, spherical harmonic illumination modeling is investigated and integrated into both stages. The robustness and accuracy of the proposed algorithm are demonstrated through experiments on various objects in both indoor and outdoor environments. Moreover, real-time performance can be achieved with graphics processing unit acceleration.
In the present work, a simulation system is proposed that can be used as an educational tool by physicians in training basic skills of minimally invasive vascular interventions. In order to accomplish this objective, initially the physical model of the wire proposed by Konings has been improved. As a result, a simpler and more stable method was obtained to calculate the equilibrium configuration of the wire. In addition, a geometrical method is developed to perform relaxations. It is particularly useful when the wire is hindered in the physical method because of the boundary conditions. Then a recipe is given to merge the physical and the geometrical methods, resulting in efficient relaxations. Moreover, tests have shown that the shape of the virtual wire agrees with the experiment. The proposed algorithm allows real-time executions, and furthermore, the hardware to assemble the simulator has a low cost.
A complete simulation system is proposed that can be used as an educational tool by physicians in training basic skills of Minimally Invasive Vascular Interventions. In the first part, a surface model is developed to assemble arteries having a planar segmentation. It is based on Sweep Surfaces and can be extended to T- and Y-like bifurcations. A continuous force vector field is described, representing the interaction between the catheter and the surface. The computation time of the force field is almost unaffected when the resolution of the artery is increased.
The mechanical properties of arteries play an essential role in the study of the circulatory system dynamics, which has been becoming increasingly important in the treatment of cardiovascular diseases. In Virtual Reality Simulators, it is crucial to have a tissue model that responds in real time. In this work, the arteries are discretized by a two dimensional mesh and the nodes are connected by three kinds of linear springs. Three tissue layers (Intima, Media, Adventitia) are considered and, starting from the stretch-energy density, some of the elasticity tensor components are calculated. The physical model linearizes and homogenizes the material response, but it still contemplates the geometric nonlinearity. In general, if the arterial stretch varies by 1% or less, then the agreement between the linear and nonlinear models is trustworthy.
In the last part, the physical model of the wire proposed by Konings is improved. As a result, a simpler and more stable method is obtained to calculate the equilibrium configuration of the wire. In addition, a geometrical method is developed to perform relaxations. It is particularly useful when the wire is hindered in the physical method because of the boundary conditions. The physical and the geometrical methods are merged, resulting in efficient relaxations. Tests show that the shape of the virtual wire agrees with the experiment. The proposed algorithm allows real-time executions and the hardware to assemble the simulator has a low cost.
Group-based communication is a highly popular communication paradigm, which is especially prominent in mobile instant messaging (MIM) applications, such as WhatsApp. Chat groups in MIM applications facilitate the sharing of various types of messages (e.g., text, voice, image, video) among a large number of participants. As each message has to be transmitted to every other member of the group, which multiplies the traffic, this has a massive impact on the underlying communication networks. However, most chat groups are private and network operators cannot obtain deep insights into MIM communication via network measurements due to end-to-end encryption. Thus, the generation of traffic is not well understood, given that it depends on sizes of communication groups, speed of communication, and exchanged message types. In this work, we provide a huge data set of 5,956 private WhatsApp chat histories, which contains over 76 million messages from more than 117,000 users. We describe and model the properties of chat groups and users, and the communication within these chat groups, which gives unprecedented insights into private MIM communication. In addition, we conduct exemplary measurements for the most popular message types, which empower the provided models to estimate the traffic over time in a chat group.