Search Results for author: Christian S. Jensen

Found 35 papers, 14 papers with code

A Unified Replay-based Continuous Learning Framework for Spatio-Temporal Prediction on Streaming Data

no code implementations23 Apr 2024 Hao Miao, Yan Zhao, Chenjuan Guo, Bin Yang, Kai Zheng, Feiteng Huang, Jiandong Xie, Christian S. Jensen

The widespread deployment of wireless and mobile devices results in a proliferation of spatio-temporal data that is used in applications, e. g., traffic prediction, human mobility mining, and air quality prediction, where spatio-temporal prediction is often essential to enable safety, predictability, or reliability.

Data Augmentation Traffic Prediction

QCore: Data-Efficient, On-Device Continual Calibration for Quantized Models -- Extended Version

1 code implementation22 Apr 2024 David Campos, Bin Yang, Tung Kieu, Miao Zhang, Chenjuan Guo, Christian S. Jensen

The first difficulty in enabling continual calibration on the edge is that the full training data may be too large and thus not always available on edge devices.

Continual Learning

TFB: Towards Comprehensive and Fair Benchmarking of Time Series Forecasting Methods

1 code implementation29 Mar 2024 Xiangfei Qiu, Jilin Hu, Lekui Zhou, Xingjian Wu, Junyang Du, Buang Zhang, Chenjuan Guo, Aoying Zhou, Christian S. Jensen, Zhenli Sheng, Bin Yang

Next, we employ TFB to perform a thorough evaluation of 21 Univariate Time Series Forecasting (UTSF) methods on 8, 068 univariate time series and 14 Multivariate Time Series Forecasting (MTSF) methods on 25 datasets.

Benchmarking Multivariate Time Series Forecasting +2

Missing Value Imputation for Multi-attribute Sensor Data Streams via Message Propagation (Extended Version)

1 code implementation13 Nov 2023 Xiao Li, Huan Li, Hua Lu, Christian S. Jensen, Varun Pandey, Volker Markl

First, we propose a message propagation imputation network (MPIN) that is able to recover the missing values of data instances in a time window.

Attribute Imputation

Exploring Progress in Multivariate Time Series Forecasting: Comprehensive Benchmarking and Heterogeneity Analysis

3 code implementations9 Oct 2023 Zezhi Shao, Fei Wang, Yongjun Xu, Wei Wei, Chengqing Yu, Zhao Zhang, Di Yao, Guangyin Jin, Xin Cao, Gao Cong, Christian S. Jensen, Xueqi Cheng

Moreover, based on the proposed BasicTS and rich heterogeneous MTS datasets, we conduct an exhaustive and reproducible performance and efficiency comparison of popular models, providing insights for researchers in selecting and designing MTS forecasting models.

Benchmarking Multivariate Time Series Forecasting +1

Origin-Destination Travel Time Oracle for Map-based Services

no code implementations6 Jul 2023 Yan Lin, Huaiyu Wan, Jilin Hu, Shengnan Guo, Bin Yang, Youfang Lin, Christian S. Jensen

Given an origin (O), a destination (D), and a departure time (T), an Origin-Destination (OD) travel time oracle~(ODT-Oracle) returns an estimate of the time it takes to travel from O to D when departing at T. ODT-Oracles serve important purposes in map-based services.

Travel Time Estimation

CHGNN: A Semi-Supervised Contrastive Hypergraph Learning Network

no code implementations10 Mar 2023 Yumeng Song, Yu Gu, Tianyi Li, Jianzhong Qi, Zhenghao Liu, Christian S. Jensen, Ge Yu

However, recent studies on hypergraph learning that extend graph convolutional networks to hypergraphs cannot learn effectively from features of unlabeled data.

Contrastive Learning Node Classification

LightTS: Lightweight Time Series Classification with Adaptive Ensemble Distillation -- Extended Version

1 code implementation24 Feb 2023 David Campos, Miao Zhang, Bin Yang, Tung Kieu, Chenjuan Guo, Christian S. Jensen

First, we propose adaptive ensemble distillation that assigns adaptive weights to different base models such that their varying classification capabilities contribute purposefully to the training of the lightweight model.

Classification Decision Making +4

LightCTS: A Lightweight Framework for Correlated Time Series Forecasting

1 code implementation23 Feb 2023 Zhichen Lai, Dalin Zhang, Huan Li, Christian S. Jensen, Hua Lu, Yan Zhao

Many deep learning models have been proposed to improve the accuracy of CTS forecasting.

 Ranked #1 on Traffic Prediction on PeMS04 (FLOPs(M) metric, using extra training data)

Computational Efficiency Correlated Time Series Forecasting +4

A Pattern Discovery Approach to Multivariate Time Series Forecasting

no code implementations20 Dec 2022 Yunyao Cheng, Chenjuan Guo, KaiXuan Chen, Kai Zhao, Bin Yang, Jiandong Xie, Christian S. Jensen, Feiteng Huang, Kai Zheng

To capture the temporal and multivariate correlations among subsequences, we design a pattern discovery model, that constructs correlations via diverse pattern functions.

Multivariate Time Series Forecasting Time Series

Joint Neural Architecture and Hyperparameter Search for Correlated Time Series Forecasting

no code implementations29 Nov 2022 Xinle Wu, Dalin Zhang, Miao Zhang, Chenjuan Guo, Bin Yang, Christian S. Jensen

To overcome these limitations, we propose SEARCH, a joint, scalable framework, to automatically devise effective CTS forecasting models.

Correlated Time Series Forecasting Time Series

A Comparative Study on Unsupervised Anomaly Detection for Time Series: Experiments and Analysis

no code implementations10 Sep 2022 Yan Zhao, Liwei Deng, Xuanhao Chen, Chenjuan Guo, Bin Yang, Tung Kieu, Feiteng Huang, Torben Bach Pedersen, Kai Zheng, Christian S. Jensen

The continued digitization of societal processes translates into a proliferation of time series data that cover applications such as fraud detection, intrusion detection, and energy management, where anomaly detection is often essential to enable reliability and safety.

energy management Fraud Detection +5

Design Automation for Fast, Lightweight, and Effective Deep Learning Models: A Survey

no code implementations22 Aug 2022 Dalin Zhang, KaiXuan Chen, Yan Zhao, Bin Yang, Lina Yao, Christian S. Jensen

A key challenge is that while the application of deep models often incurs substantial memory and computational costs, edge devices typically offer only very limited storage and computational capabilities that may vary substantially across devices.

Edge-computing Model Compression +1

Pre-training General Trajectory Embeddings with Maximum Multi-view Entropy Coding

no code implementations29 Jul 2022 Yan Lin, Huaiyu Wan, Shengnan Guo, Jilin Hu, Christian S. Jensen, Youfang Lin

Spatio-temporal trajectories provide valuable information about movement and travel behavior, enabling various downstream tasks that in turn power real-world applications.

Contrastive Learning Data Augmentation

Decoupled Dynamic Spatial-Temporal Graph Neural Network for Traffic Forecasting

1 code implementation18 Jun 2022 Zezhi Shao, Zhao Zhang, Wei Wei, Fei Wang, Yongjun Xu, Xin Cao, Christian S. Jensen

However, intuitively, traffic data encompasses two different kinds of hidden time series signals, namely the diffusion signals and inherent signals.

Graph Learning Time Series Forecasting +1

Robust and Explainable Autoencoders for Unsupervised Time Series Outlier Detection---Extended Version

no code implementations7 Apr 2022 Tung Kieu, Bin Yang, Chenjuan Guo, Christian S. Jensen, Yan Zhao, Feiteng Huang, Kai Zheng

This is an extended version of "Robust and Explainable Autoencoders for Unsupervised Time Series Outlier Detection", to appear in IEEE ICDE 2022.

Outlier Detection Time Series +1

Weakly-supervised Temporal Path Representation Learning with Contrastive Curriculum Learning -- Extended Version

1 code implementation30 Mar 2022 Sean Bin Yang, Chenjuan Guo, Jilin Hu, Bin Yang, Jian Tang, Christian S. Jensen

In this setting, it is essential to learn generic temporal path representations(TPRs) that consider spatial and temporal correlations simultaneously and that can be used in different applications, i. e., downstream tasks.

Contrastive Learning Representation Learning +1

AutoCTS: Automated Correlated Time Series Forecasting -- Extended Version

no code implementations21 Dec 2021 Xinle Wu, Dalin Zhang, Chenjuan Guo, Chaoyang He, Bin Yang, Christian S. Jensen

Specifically, we design both a micro and a macro search space to model possible architectures of ST-blocks and the connections among heterogeneous ST-blocks, and we provide a search strategy that is able to jointly explore the search spaces to identify optimal forecasting models.

Correlated Time Series Forecasting Time Series

Deep Spatially and Temporally Aware Similarity Computation for Road Network Constrained Trajectories

1 code implementation17 Dec 2021 Ziquan Fang, Yuntao Du, Xinjun Zhu, Lu Chen, Yunjun Gao, Christian S. Jensen

Trajectory similarity computation has drawn massive attention, as it is core functionality in a wide range of applications such as ride-sharing, traffic analysis, and social recommendation.

Representation Learning

Unsupervised Time Series Outlier Detection with Diversity-Driven Convolutional Ensembles -- Extended Version

no code implementations22 Nov 2021 David Campos, Tung Kieu, Chenjuan Guo, Feiteng Huang, Kai Zheng, Bin Yang, Christian S. Jensen

To improve accuracy, the ensemble employs multiple basic outlier detection models built on convolutional sequence-to-sequence autoencoders that can capture temporal dependencies in time series.

Outlier Detection Time Series +1

UniTE -- The Best of Both Worlds: Unifying Function-Fitting and Aggregation-Based Approaches to Travel Time and Travel Speed Estimation

no code implementations27 Apr 2021 Tobias Skovgaard Jepsen, Christian S. Jensen, Thomas Dyhre Nielsen

An empirical study finds that an instance of UniTE can improve the accuracies of travel speed distribution and travel time estimation by $40-64\%$ and $3-23\%$, respectively, compared to using function fitting or aggregation alone

Travel Time Estimation

SOUP: Spatial-Temporal Demand Forecasting and Competitive Supply

no code implementations24 Sep 2020 Bolong Zheng, Qi Hu, Lingfeng Ming, Jilin Hu, Lu Chen, Kai Zheng, Christian S. Jensen

In this setting, an assignment authority is to assign agents to requests such that the average idle time of the agents is minimized.

Databases Signal Processing

Relational Fusion Networks: Graph Convolutional Networks for Road Networks

1 code implementation16 Jun 2020 Tobias Skovgaard Jepsen, Christian S. Jensen, Thomas Dyhre Nielsen

The application of machine learning techniques in the setting of road networks holds the potential to facilitate many important intelligent transportation applications.

BIG-bench Machine Learning

Graph Convolutional Networks for Road Networks

1 code implementation30 Aug 2019 Tobias Skovgaard Jepsen, Christian S. Jensen, Thomas Dyhre Nielsen

In addition, we provide experimental evidence of the short-comings of state-of-the-art GCNs in the context of road networks: unlike our method, they cannot effectively leverage the road network structure for road segment classification and fail to outperform a regular multi-layer perceptron.

Attribute BIG-bench Machine Learning +3

Recurrent Multi-Graph Neural Networks for Travel Cost Prediction

no code implementations13 Nov 2018 Jilin Hu, Chenjuan Guo, Bin Yang, Christian S. Jensen, Lu Chen

Origin-destination (OD) matrices are often used in urban planning, where a city is partitioned into regions and an element (i, j) in an OD matrix records the cost (e. g., travel time, fuel consumption, or travel speed) from region i to region j.

Learning to Route with Sparse Trajectory Sets---Extended Version

no code implementations22 Feb 2018 Chenjuan Guo, Bin Yang, Jilin Hu, Christian S. Jensen

In the second step, we exploit the above graph-like structure to achieve a comprehensive trajectory-based routing solution.

Clustering

Using Incomplete Information for Complete Weight Annotation of Road Networks -- Extended Version

no code implementations2 Aug 2013 Bin Yang, Manohar Kaul, Christian S. Jensen

This paper formulates and addresses the problem of annotating all edges in a road network with travel cost based weights from a set of trips in the network that cover only a small fraction of the edges, each with an associated ground-truth travel cost.

Cannot find the paper you are looking for? You can Submit a new open access paper.