1 code implementation • 4 Sep 2024 • Yuexuan Xu, Jianyang Gao, Yutong Gou, Cheng Long, Christian S. Jensen
In this study, instead of materializing a compressed index for every possible query range in preparation for querying, we materialize graph-based indexes, called elemental graphs, for a moderate number of ranges.
1 code implementation • 17 Jul 2024 • Yan Lin, Zeyu Zhou, Yicheng Liu, Haochen Lv, Haomin Wen, Tianyi Li, Yushuai Li, Christian S. Jensen, Shengnan Guo, Youfang Lin, Huaiyu Wan
However, research progress on this topic faces two key challenges: a lack of a comprehensive overview of existing methods, resulting in several related methods not being well-recognized, and the absence of a unified pipeline, complicating the development new methods and the analysis of methods.
no code implementations • 15 May 2024 • Qianru Zhang, Haixin Wang, Cheng Long, Liangcai Su, Xingwei He, Jianlong Chang, Tailin Wu, Hongzhi Yin, Siu-Ming Yiu, Qi Tian, Christian S. Jensen
By integrating generative techniques and providing a standardized framework, the paper contributes to advancing the field and encourages researchers to explore the vast potential of generative techniques in spatial-temporal data mining.
no code implementations • 23 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.
1 code implementation • 22 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.
1 code implementation • 29 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.
1 code implementation • 25 Mar 2024 • Qianru Zhang, Lianghao Xia, Xuheng Cai, SiuMing Yiu, Chao Huang, Christian S. Jensen
To address these challenges, we propose a principled framework called GraphAug.
1 code implementation • 21 Feb 2024 • Zhichen Lai, Huan Li, Dalin Zhang, Yan Zhao, Weizhu Qian, Christian S. Jensen
We propose E2Usd that enables efficient-yet-accurate unsupervised MTS state detection.
1 code implementation • 11 Feb 2024 • Yan Lin, Jilin Hu, Shengnan Guo, Bin Yang, Christian S. Jensen, Youfang Lin, Huaiyu Wan
However, most methods target only one specific task and cannot be applied universally.
no code implementations • 26 Jan 2024 • Mengna Liu, Dong Xiang, Xu Cheng, Xiufeng Liu, Dalin Zhang, ShengYong Chen, Christian S. Jensen
To address these challenges, we propose a multilevel heterogeneous neural network, called MHNN, for sensor data analysis.
no code implementations • 27 Dec 2023 • Minbo Ma, Jilin Hu, Christian S. Jensen, Fei Teng, Peng Han, Zhiqiang Xu, Tianrui Li
Spatio-temporal forecasting of future values of spatially correlated time series is important across many cyber-physical systems (CPS).
1 code implementation • 13 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.
3 code implementations • 9 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.
no code implementations • 19 Jul 2023 • Sean Bin Yang, Jilin Hu, Chenjuan Guo, Bin Yang, Christian S. Jensen
Next, we propose a relational reasoning framework to enable faster training of more robust sparse path encoders.
no code implementations • 6 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.
no code implementations • 10 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.
1 code implementation • 24 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.
1 code implementation • 23 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
no code implementations • 20 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.
no code implementations • 29 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.
no code implementations • 10 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.
no code implementations • 22 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.
no code implementations • 29 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.
1 code implementation • 18 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.
Ranked #4 on Traffic Prediction on PEMS-BAY
no code implementations • 7 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.
1 code implementation • 30 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.
no code implementations • 21 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.
1 code implementation • 17 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.
no code implementations • 22 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.
no code implementations • 27 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
no code implementations • 24 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
1 code implementation • 16 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.
no code implementations • 14 Nov 2019 • Tobias Skovgaard Jepsen, Christian S. Jensen, Thomas Dyhre Nielsen
This is problematic for analysis tasks that rely on such information for machine learning.
1 code implementation • 30 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.
no code implementations • 13 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.
no code implementations • 22 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.
no code implementations • 2 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.