yusuke1997/dblp-id-title huggingface dataset:
Adaptive Event-Triggered Fast Finite-Time Stabilization of High-Order Uncertain Nonlinear Systems and its Application in Maglev Systems
A Divide-and-Conquer Bilevel Optimization Algorithm for Jointly Pricing Computing Resources and Energy in Wireless Powered MEC
Distributed Event-Triggered Estimation Over Sensor Networks: A Survey
Generalized 2-D Principal Component Analysis by Lp-Norm for Image Analysis
Loop Closure Detection by Algorithmic Information Theory: Implemented on Range and Camera Image Data
Predictor-Based Neural Dynamic Surface Control for Strict-Feedback Nonlinear Systems With Unknown Control Gains
Fault Detection for Nonlinear Process With Deterministic Disturbances: A Just-In-Time Learning Based Data Driven Method
Correlation Dimension-Based Classifier
Acquisition of Causal Models for Local Distributions in Bayesian Networks
A Secure Adaptive Control for Cooperative Driving of Autonomous Connected Vehicles in the Presence of Heterogeneous Communication Delays and Cyberattacks
Fine-Grained Unsupervised Temporal Action Segmentation and Distributed Representation for Skeleton-Based Human Motion Analysis
Hierarchical Containment Control With Bipartite Cluster Consensus for Heterogeneous Multiagent Systems Under Layer-Signed Digraph
A Generic Method for the Evaluation of Interval Type-2 Fuzzy Linguistic Summaries
A Sampled-Data-Based Secure Control Approach for Networked Control Systems Under Random DoS Attacks
Efficient Approach for RLS Type Learning in TSK Neural Fuzzy Systems
Dual Regression-Enhanced Gaze Target Detection in the Wild
Saturated Adaptive Fuzzy Fixed-Time Nonsingular Integral Terminal Sliding-Mode Control of AUVs
Hybrid Regularized Echo State Network for Multivariate Chaotic Time Series Prediction
Low-Complexity Distributed Prescribed Performance Control of Unknown Nonlinear Multiagent Systems Under Switching Topologies
Distributed Graph Hashing
Multicontroller-Based Fault-Tolerant Control for Uncertain High-Order Sub-Fully Actuated Systems
Efficient Video Stitching Based on Fast Structure Deformation
Dynamic Event-Triggered Safe Control for Nonlinear Game Systems With Asymmetric Input Saturation
Deep Pain: Exploiting Long Short-Term Memory Networks for Facial Expression Classification
Classifying a Person's Degree of Accessibility From Natural Body Language During Social Human-Robot Interactions
Saliency-Based Multilabel Linear Discriminant Analysis
Robot-Assisted Pedestrian Regulation Based on Deep Reinforcement Learning
Fuzzy Rule-Based Design of Evolutionary Algorithm for Optimization
Entanglement Measure-Based Sliding Mode Control for Quantum State Preparation
Hierarchical Heuristic Search Using a Gaussian Mixture Model for UAV Coverage Planning
Fused Sparse Network Learning for Longitudinal Analysis of Mild Cognitive Impairment
Nussbaum-Based Adaptive Fault-Tolerant Control for Nonlinear CPSs With Deception Attacks: A New Coordinate Transformation Technology
Fast UAV Object-Searching in Large-Scale and Complex Environments
Top-k Self-Adaptive Contrast Sequential Pattern Mining
Learning to Solve 3-D Bin Packing Problem via Deep Reinforcement Learning and Constraint Programming
Prespecified-Time Cluster Synchronization of Complex Networks via a Smooth Control Approach
Networked Estimation of a Class of Fuzzy Stochastic Hybrid Systems With Variable Rates of Packet Losses
Identification of Fuzzy Rule-Based Models With Collaborative Fuzzy Clustering
Distributed Resilient Estimator Design for Positive Systems Under Topological Attacks
Distributed Consensus Seeking With Different Convergence Performance Requirements: A Unified Control Framework
Hybrid Metaheuristic Approaches to the Expectation Maximization for Estimation of the Hidden Markov Model for Signal Modeling
Fault Estimation Observer Design for Discrete-Time Takagi-Sugeno Fuzzy Systems Based on Homogenous Polynomially Parameter-Dependent Lyapunov Functions
Editorial: The Transactions in Transition
Robust Adaptive Fixed-Time Sliding-Mode Control for Uncertain Robotic Systems With Input Saturation
Adaptive Anti-Disturbance Control for a Class of Uncertain Nonlinear Systems With Composite Disturbances
Model-Free Control in Wireless Cyber-Physical System With Communication Latency: A DRL Method With Improved Experience Replay
Regionwise Generative Adversarial Image Inpainting for Large Missing Areas
A Multiobjective Evolutionary Algorithm Based on Similarity for Community Detection From Signed Social Networks
Parallel Intelligent Systems for Integrated High-Speed Railway Operation Control and Dynamic Scheduling
An FDES-Based Shared Control Method for Asynchronous Brain-Actuated Robot
Consensus Affinity Graph Learning for Multiple Kernel Clustering
Distributed Event-Triggered Quantized Fault-Tolerant Control of Linear Multiagent Systems With External Disturbances and Parameter Uncertainties
Energy-Efficient Optimal Sensor Scheduling for State Estimation Over Multihop Sensor Networks
Distributed Formation Control of Multiple Euler-Lagrange Systems: A Multilayer Framework
Sampled-Data Asynchronous Control for Switched Nonlinear Systems With Relaxed Switching Rules
Command-Filtered Neuroadaptive Output-Feedback Control for Stochastic Nonlinear Systems With Input Constraint
Understanding the Dimensional Need of Noncontrastive Learning
Learning Spatio-Temporal Representations for Action Recognition: A Genetic Programming Approach
Neural Networks Enhanced Adaptive Admittance Control of Optimized Robot-Environment Interaction
Improved Event-Triggered Dynamic Output Feedback Control for Networked T-S Fuzzy Systems With Actuator Failure and Deception Attacks
Delayed Feedback-Based Suppression of Pathological Oscillations in a Neural Mass Model
Early Screening of Autism in Toddlers via Response-To-Instructions Protocol
Discriminant Kernel Assignment for Image Coding
Solving Nonlinear Optimization Problems of Real Functions in Complex Variables by Complex-Valued Iterative Methods
Diff-MTS: Temporal-Augmented Conditional Diffusion-Based AIGC for Industrial Time Series Toward the Large Model Era
Optimizing Niche Center for Multimodal Optimization Problems
Design and Performance Analysis of Incremental Networked Predictive Control Systems
Semantic Feature Learning for Heterogeneous Multitask Classification via Non-Negative Matrix Factorization
IKT-BT: Indirect Knowledge Transfer Behavior Tree Framework for Multirobot Systems Through Communication Eavesdropping
Learning Fuzzy Automaton's Event Transition Matrix When Post-Event State Is Unknown
Memory-Efficient Inverse Reinforcement Learning for Multiplayer Differential Games
A Novel Cyber Attack Detection Method in Networked Control Systems
Data-Based Reinforcement Learning for Nonzero-Sum Games With Unknown Drift Dynamics
Adaptive Consensus Tracking Control of Uncertain Nonlinear Multiagent Systems With Predefined Accuracy
Discriminative Mixture Variational Autoencoder for Semisupervised Classification
Reliable Filter Design of Takagi-Sugeno Fuzzy Switched Systems With Imprecise Modes
Data-Driven Distributed Predictive Control for Voltage Regulation and Current Sharing in DC Microgrids With Communication Constraints
Novel Dynamic Event-Triggered Consensus Control of Multiagent Systems With Markovian Switching Topologies Under DoS Attacks
Motion Planning and Tracking MPC for Multiagent Systems: A Dynamic Affine Formation Approach
Semi-Supervised Nonnegative Matrix Factorization via Constraint Propagation
Human-in-the-Loop Cooperative Control of a Walking Exoskeleton for Following Time-Variable Human Intention
MPC-Based Cooperative Enclosing for Nonholonomic Mobile Agents Under Input Constraint and Unknown Disturbance
Prescribed Performance Cooperative Control for Multiagent Systems With Input Quantization
Data-Based Output Synchronization of Discrete-Time Heterogeneous Multiagent Systems With Sensor Faults
Enhancing SMT Quality and Efficiency With Self-Adaptive Collaborative Optimization
Iterative Learning Control for MIMO Nonlinear Systems With Iteration-Varying Trial Lengths Using Modified Composite Energy Function Analysis
ATM-R: An Adaptive Tradeoff Model With Reference Points for Constrained Multiobjective Evolutionary Optimization
Granular Robust Mean-CVaR Feedstock Flow Planning for Waste-to-Energy Systems Under Integrated Uncertainty
A Distributed k-Winners-Take-All Model With Binary Consensus Protocols
Discovering Multiple Co-Clusterings With Matrix Factorization
DeepVolume: Brain Structure and Spatial Connection-Aware Network for Brain MRI Super-Resolution
A Novel Neural Dynamics Controller for Weakening the Chaos of Permanent Magnet Synchronous Generator and Its Extended Application
Pervasive Sound Sensing: A Weakly Supervised Training Approach
Predictor-Based Extended-State-Observer Design for Consensus of MASs With Delays and Disturbances
Learning the Inverse Dynamics of Robotic Manipulators in Structured Reproducing Kernel Hilbert Space
ExS-GAN: Synthesizing Anti-Forensics Images via Extra Supervised GAN
Synchronization in Kuramoto Oscillator Networks With Sampled-Data Updating Law
Containment Control of Multiagent Systems With Dynamic Leaders Based on a $PI^{n}$ -Type Approach
Development and Investigation of a Long-Range Time-of-Flight and Color Imaging System
Efficient Unsupervised Dimension Reduction for Streaming Multiview Data
A Packet Loss-Dependent Event-Triggered Cyber-Physical Cooperative Control Strategy for Islanded Microgrid
Automatic Update Summarization by a Multiobjective Number-One-Selection Genetic Approach
Learning Sequential Composition Control
Active Interdiction Defence Scheme Against False Data-Injection Attacks: A Stackelberg Game Perspective
Double Threshold Structure of Sensor Scheduling Policy Over a Finite-State Markov Channel
L ∞ Bumpless Transfer Fault-Tolerant Control for Continuous-Time Switched Systems via Learning-Based Fault Reconstruction
Distributed Control for Nonlinear Time-Delay Multiagent Systems: Hybrid Saturation-Constraint Impulsive Approach
Scale-Limited Lagrange Stability and Finite-Time Synchronization for Memristive Recurrent Neural Networks on Time Scales
Dynamic MOPSO-Based Optimal Control for Wastewater Treatment Process
Dynamically Modulated Mask Sparse Tracking
Dynamic Task Assignment and Path Planning of Multi-AUV System Based on an Improved Self-Organizing Map and Velocity Synthesis Method in Three-Dimensional Underwater Workspace
Evolving Scheduling Heuristics via Genetic Programming With Feature Selection in Dynamic Flexible Job-Shop Scheduling
Optimal Object Association in the Dempster-Shafer Framework
Active Security Control for Switched Systems Under Deception and DoS Attacks Based on Two-Tier Stackelberg Game
Optimal Trajectory Planning Method for the Navigation of WIP Vehicles in Unknown Environments: Theory and Experiment
Adaptive Neural Network Control of an Uncertain Robot With Full-State Constraints
Event-Triggered Active MPC for Nonlinear Multiagent Systems With Packet Losses
Audio-Driven Robot Upper-Body Motion Synthesis
Cooperative Control and Performance Evaluation of a Linear MIMO Parabolic Spatiotemporal Dynamic System on Directed and Switching Topologies
Construction of Barrier in a Fishing Game With Point Capture
Sampled-Data Model-Free Adaptive Control for Nonlinear Continuous-Time Systems
A Neighborhood Regression Optimization Algorithm for Computationally Expensive Optimization Problems
Integrated Decision and Control: Toward Interpretable and Computationally Efficient Driving Intelligence
Auxiliary Demographic Information Assisted Age Estimation With Cascaded Structure
Invariance Principles for Nonlinear Discrete-Time Switched Systems and Its Application to Output Synchronization of Dynamical Networks
Difference of Convex Functions Programming With Machine-Learning Prior for the Imaging Problem in Electrical Capacitance Tomography
Hybrid Residual Multiexpert Reinforcement Learning for Spatial Scheduling of High-Density Parking Lots
Game-Based Approximate Optimal Motion Planning for Safe Human-Swarm Interaction
The Real Eigenpairs of Symmetric Tensors and Its Application to Independent Component Analysis
Improving Metaheuristic Algorithms With Information Feedback Models
Evolutionary Weighted Broad Learning and Its Application to Fault Diagnosis in Self-Organizing Cellular Networks
Fuzzy Adaptive Knowledge-Based Inference Neural Networks: Design and Analysis
Intraspectrum Discrimination and Interspectrum Correlation Analysis Deep Network for Multispectral Face Recognition
Authentic Boundary Proximal Policy Optimization
Finite-Horizon H ∞ Consensus for Multiagent Systems With Redundant Channels via An Observer-Type Event-Triggered Scheme
Takagi-Sugeno Fuzzy Models in the Framework of Orthonormal Basis Functions
Erratum: Event-Triggered Consensus of Homogeneous and Heterogeneous Multiagent Systems With Jointly Connected Switching Topologies
An Online Unsupervised Dynamic Window Method to Track Repeating Patterns From Sensor Data
Necessary and Sufficient Conditions on Pinning Stabilization for Stochastic Boolean Networks
SOS Based Robust H ∞ Fuzzy Dynamic Output Feedback Control of Nonlinear Networked Control Systems
Resilient Distributed Control in the Presence of Misbehaving Agents in Networked Control Systems
Social Synchrony on Complex Networks
Effective Control Method Based on Trajectory Optimization for Three-Link Vertical Underactuated Manipulators With Only One Active Joint
A Study on the Security Levels of Spread-Spectrum Embedding Schemes in the WOA Framework
On Containment for Linear Systems With Switching Topologies: A Novel State Transition Matrix Perspective
Multiview Semantic Representation for Visual Recognition
Fuzzy Control Design of Nonlinear Time-Delay Parabolic PDE Systems Under Mobile Collocated Actuators and Sensors
Clustering by Local Gravitation
Consensus Tracking for High-Order Uncertain Nonlinear MASs via Adaptive Backstepping Approach
Event-Triggered Adaptive Control of Uncertain Strict-Feedback Nonlinear Systems Using Fully Actuated System Approach
A Survey of Imitation Learning: Algorithms, Recent Developments, and Challenges
Weighted Hierarchical Grammatical Evolution
A Multiobjective Framework for Many-Objective Optimization
A Q-Learning Approach to Flocking With UAVs in a Stochastic Environment
Efficiency-Driven Adaptive Task Planning for Household Robot Based on Hierarchical Item-Environment Cognition
Relaxed LMI Conditions for Local Stability and Local Stabilization of Continuous-Time Takagi-Sugeno Fuzzy Systems
SVD-Based Robust Distributed MPC for Tracking Systems Coupled in Dynamics With Global Constraints
Hybridizing Niching, Particle Swarm Optimization, and Evolution Strategy for Multimodal Optimization
Distributed Memetic Algorithm for Outsourced Database Fragmentation
A Hybrid Artificial Immune-Simulated Annealing Algorithm for Multiroute Job Shop Scheduling Problem With Continuous Limited Output Buffers
Nonlocal Low-Rank Tensor Completion for Visual Data
An Autoencoder Framework With Attention Mechanism for Cross-Domain Recommendation
Learning Trajectories for Robot Programing by Demonstration Using a Coordinated Mixture of Factor Analyzers
Intelligent Critic Control With Robustness Guarantee of Disturbed Nonlinear Plants
Distributed Estimation With Cross-Verification Under False Data-Injection Attacks
Global Synchronization of High-Dimensional Heterogeneous Kuramoto Oscillator Networks: Pinning Impulsive Approach
Convergence Analysis of Distributed Gradient Descent Algorithms With One and Two Momentum Terms
An Efficient Second-Order Algorithm for Self-Organizing Fuzzy Neural Networks
Interrelationship-Based Selection for Decomposition Multiobjective Optimization
Controllability of Networked Sampled-Data Systems With Time Delays
MoniNet With Concurrent Analytics of Temporal and Spatial Information for Fault Detection in Industrial Processes
A Variable Projection Approach for Efficient Estimation of RBF-ARX Model
Differential Evolution With Event-Triggered Impulsive Control
A Reduced-Complexity Data-Fusion Algorithm Using Belief Propagation for Location Tracking in Heterogeneous Observations
Evolutionary Metric-Learning-Based Recognition Algorithm for Online Isolated Persian/Arabic Characters, Reconstructed Using Inertial Pen Signals
Distributed Adaptive Output Feedback Consensus of Parabolic PDE Agents on Undirected Networks
A Collaborative Learning Tracking Network for Remote Sensing Videos
Domain-Adversarial-Guided Siamese Network for Unsupervised Cross-Domain 3-D Object Retrieval
Distributed Event-Based Set-Membership Filtering for a Class of Nonlinear Systems With Sensor Saturations Over Sensor Networks
Safe Transfer-Reinforcement-Learning-Based Optimal Control of Nonlinear Systems
Compound Event-Triggered Distributed MPC for Coupled Nonlinear Systems
Multiple Environment Integral Reinforcement Learning-Based Fault-Tolerant Control for Affine Nonlinear Systems
Nonconvex Compressed Sensing by Nature-Inspired Optimization Algorithms
Weak Estimator-Based Stochastic Searching on the Line in Dynamic Dual Environments
Event-Triggered Multiasynchronous H ∞ Control for Markov Jump Systems With Transmission Delay
Differential Evolution With Two-Level Parameter Adaptation
Barrier Lyapunov Function-Based Adaptive Fault-Tolerant Control for a Class of Strict-Feedback Stochastic Nonlinear Systems
Auditory Perspective Taking
A Novel Rapid-Flooding Approach With Real-Time Delay Compensation for Wireless-Sensor Network Time Synchronization
Can We Do Better in Unimodal Biometric Systems? A Rank-Based Score Normalization Framework
SAIL: Summation-bAsed Incremental Learning for Information-Theoretic Text Clustering
Facial Skin Beautification Using Adaptive Region-Aware Masks
Automated Coordination Strategy Design Using Genetic Programming for Dynamic Multipoint Dynamic Aggregation
Implementing Kernel Methods Incrementally by Incremental Nonlinear Projection Trick
Target-Attackers-Defenders Linear-Quadratic Exponential Stochastic Differential Games With Distributed Control
Fault-Tolerant Synchronization Control of Switched Complex Networks by a Proportional-Integral Intermediate Observer Approach
Adaptive Fuzzy Control for Nontriangular Stochastic High-Order Nonlinear Systems Subject to Asymmetric Output Constraints
Autoweighted Multiview Feature Selection With Graph Optimization
Mutual Variational Inference: An Indirect Variational Inference Approach for Unsupervised Domain Adaptation
Integrated Fault-Tolerant Control Design With Sampled-Output Measurements for Interval Type-2 Takagi-Sugeno Fuzzy Systems
A Scalable Algorithm for Event-Triggered State Estimation With Unknown Parameters and Switching Topologies Over Sensor Networks
Video Decolorization Using Visual Proximity Coherence Optimization
Feature Extraction for Classification of Hyperspectral and LiDAR Data Using Patch-to-Patch CNN
Cross-Lingual Knowledge Transferring by Structural Correspondence and Space Transfer
Policy Gradient Adaptive Dynamic Programming for Data-Based Optimal Control
Improvement of Neural-Network Classifiers Using Fuzzy Floating Centroids
Hierarchical One-Class Model With Subnetwork for Representation Learning and Outlier Detection
Deformable Parts Correlation Filters for Robust Visual Tracking
Learning Domain-Invariant Subspace Using Domain Features and Independence Maximization
Fault-Tolerant Cubature Kalman Filter for Engineering Estimation Control Systems
Probabilistic Linear Discriminant Analysis Based on L 1 -Norm and Its Bayesian Variational Inference
Density-Aware Curriculum Learning for Crowd Counting
Adaptive Tracking Control of Surface Vessel Using Optimized Backstepping Technique
Distributed Observers for Linear Time-Invariant Systems With Time-Varying Delays: A Switching Event-Triggered Approach
Prioritizing Useful Experience Replay for Heuristic Dynamic Programming-Based Learning Systems
Subdomain Adaptation With Manifolds Discrepancy Alignment
Speedup 3-D Texture-Less Object Recognition Against Self-Occlusion for Intelligent Manufacturing
Filtering for Discrete-Time Takagi-Sugeno Fuzzy Nonhomogeneous Markov Jump Systems With Quantization Effects
Formation-Containment Control of Euler-Lagrange Systems of Leaders With Bounded Unknown Inputs
Switched Control of HyTAQs: A Framework of Stochastic Hybrid Fuzzy Systems With Variable Dimensions
A Nonparametric Deep Generative Model for Multimanifold Clustering
Blind Audio-Visual Localization and Separation via Low-Rank and Sparsity
Relevance Vector Machines-Based Time Series Prediction for Incomplete Training Dataset: Two Comparative Approaches
View Transformation Model Incorporating Quality Measures for Cross-View Gait Recognition
Optimal Containment Control of a Quadrotor Team With Active Leaders via Reinforcement Learning
Input Time Delay Margin in Event-Triggered Consensus of Multiagent Systems
Consensus Tracking Control of Uncertain Multiagent Systems With Sampled Data and Time-Varying Delay
Cooperation Learning From Multiple Social Networks: Consistent and Complementary Perspectives
Prescribed Fixed-Time Control for Constrained Uncertain Nonlinear Cyber-Physical Systems Against Deception Attacks
Weighted Average Consensus-Based Unscented Kalman Filtering
Robust Adaptive Fault-Tolerant Control for a Riser-Vessel System With Input Hysteresis and Time-Varying Output Constraints
Policy Iteration for H ∞ Optimal Control of Polynomial Nonlinear Systems via Sum of Squares Programming
Discrete Memristive Conservative Chaotic Map: Dynamics, Hardware Implementation, and Application in Secure Communication
Fully Distributed Optimal Position Control of Networked Uncertain Euler-Lagrange Systems Under Unbalanced Digraphs
Distributed Adaptive Control for Asymptotically Consensus Tracking of Uncertain Nonlinear Systems With Intermittent Actuator Faults and Directed Communication Topology
Optimal Regulation Strategy for Nonzero-Sum Games of the Immune System Using Adaptive Dynamic Programming
Deep Nonlinear Metric Learning for 3-D Shape Retrieval
SE(n)++: An Efficient Solution to Multiple Pose Estimation Problems
Distributed Optimization for Graph Matching
Hierarchical Optimization Design for Autonomous Flight of Vision-Based Quadrotor Using Reinforcement Learning
Encryption and Decryption of Audio Signal and Image Secure Communications Using Chaotic System Synchronization Control by TSK Fuzzy Brain Emotional Learning Controllers
High-Confidence Data-Driven Safe Tracking Control Design
Parameterized MDPs and Reinforcement Learning Problems - A Maximum Entropy Principle-Based Framework
Intelligent Fault Diagnosis for Chemical Processes Using Deep Learning Multimodel Fusion
Leveraging Long and Short-Term Information in Content-Aware Movie Recommendation via Adversarial Training
Adaptive Compensation for Nonlinear Time-Varying Multiagent Systems With Actuator Failures and Unknown Control Directions
Recursive Discriminative Subspace Learning With $\ell_{1}$ -Norm Distance Constraint
A Threshold-Parameter-Dependent Approach to Designing Distributed Event-Triggered $H_{\infty}$ Consensus Filters Over Sensor Networks
Minimal-Approximation-Based Distributed Consensus Tracking of a Class of Uncertain Nonlinear Multiagent Systems With Unknown Control Directions
Fast Finite-Time Control for Nonaffine Stochastic Nonlinear Systems Against Multiple Actuator Constraints via Output Feedback
Differential Evolution Enhanced With Multiobjective Sorting-Based Mutation Operators
Semi-Supervised Salient Object Detection Using a Linear Feedback Control System Model
The Impact of Nonminimum-Phase Zeros on Human-in-the-Loop Control Systems
Efficient Minimum Cost Seed Selection With Theoretical Guarantees for Competitive Influence Maximization
Distributed Edge-Based Nash Equilibrium Seeking With Event-Triggered Quantized Communication
Identity Recognition Based on Bioacoustics of Human Body
GRESS: Grouping Belief-Based Deep Contrastive Subspace Clustering
Fatigue Detection of Pilots' Brain Through Brains Cognitive Map and Multilayer Latent Incremental Learning Model
Heterogeneous Domain Adaptation via Covariance Structured Feature Translators
A Dynamic-Memory Event-Triggered Protocol to Multiarea Power Systems With Semi-Markov Jumping Parameter
An Efficient Iterative Learning Predictive Functional Control for Nonlinear Batch Processes
Interval Observer-Based Fault Isolation for Discrete-Time Fuzzy Interconnected Systems With Unknown Interconnections