Publications

CSSG: A Continuous Spatio-temporal Graph Learning Framework with Scalable Spatial Granularity

Published in SIGKDD, 2026

Public Health Emergencies (PHEs) pose serious threats to public health and cause socio-economic disruptions. During such events, mobility restrictions lead to a surge in online shopping for daily supplies. Predicting multi-category product demand under PHEs is essential to help e-commerce and logistics companies improve the efficiency of material management and regional distribution. However, shifting policy interventions alter both population distribution and consumer intent, making demand prediction particularly challenging. In this paper, we propose M2DP, a novel multi-scale association learning framework for multi-category demand prediction under PHEs. Our approach includes: (1) multi-scale temporal encoders to extract long/short-term demand patterns and an event evolution module to incorporate regional impacts; (2) a dual association learning module that integrates both empirical and adaptive category correlations; and (3) a regional joint prediction module that combines temporal and associative features via a spatial graph for final forecasting. Experiments on real-world e-commerce data show that our model achieves state-of-the-art performance.

Recommended citation: Xia, K., Lin, L., Zhang, Q., Zhang, X., & Wang, S., Hu X. & Yu P (2026, August). CSSG: A Continuous Spatio-temporal Graph Learning Framework with Scalable Spatial Granularity. In Proceedings of the 32st ACM SIGKDD Conference on Knowledge Discovery and Data Mining. 2026.

M2DP: A Multi-Scale Association Learning Framework for Multi-Category Demand Prediction under Public Health Emergencies

Published in IEEE ICASSP, 2026

Public Health Emergencies (PHEs) pose serious threats to public health and cause socio-economic disruptions. During such events, mobility restrictions lead to a surge in online shopping for daily supplies. Predicting multi-category product demand under PHEs is essential to help e-commerce and logistics companies improve the efficiency of material management and regional distribution. However, shifting policy interventions alter both population distribution and consumer intent, making demand prediction particularly challenging. In this paper, we propose M2DP, a novel multi-scale association learning framework for multi-category demand prediction under PHEs. Our approach includes: (1) multi-scale temporal encoders to extract long/short-term demand patterns and an event evolution module to incorporate regional impacts; (2) a dual association learning module that integrates both empirical and adaptive category correlations; and (3) a regional joint prediction module that combines temporal and associative features via a spatial graph for final forecasting. Experiments on real-world e-commerce data show that our model achieves state-of-the-art performance.

Recommended citation: Zhang, X., Lin, L., Xia, K., Feng Y., Zhang, Q. & Wang, S. (2026, May). M2DP: A Multi-Scale Association Learning Framework for Multi-Category Demand Prediction under Public Health Emergencies. In IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). 2026.

ORTCL: Towards Continual Learning of Time Series Foundation Models on Streaming Data via Orthogonal Rotation

Published in AAAI, 2026

Time Series Foundation Models (TSFMs) have emerged as a promising approach in time series analysis. Due to the large-scale parameters of TSFMs and pretraining cost, how to adapt TDFMs in streaming data is always the key factor constraining their application effectiveness. Because streaming data often experiences data distribution and task drifts, which cannot be learnt by offline training. Existing methods typically address streaming data modeling with continuous learning through model fine-tuning or model editing. However, fine-tuning incurs significant computational costs, while editing methods can lead to shifts in the original feature space during streaming updates. To address these limitations, we propose a novel Orthogonal Rotation Transformation-based Continuous Learning method, called ORTCL, for TSFMs. Our key insight is to apply orthogonal matrix rotations to the input and output feature spaces of the TSFMs during model editing. This preserves the metric structure of the original feature space and enables new data to be directly mapped into the existing feature space of the TSFMs. Specifically, we obtain the orthogonal matrix for the input layer via singular value decomposition and derive the corresponding transfor mation matrix for the output layer through least squares optimization. Extensive experimental results demonstrate that ORTCL outperforms existing methods in both single-domain and cross-domain streaming time series forecasting tasks, effectively mitigating catastrophic forgetting.

Recommended citation: Lin, L., Zhang, X., Zhang, Q., Wang, S. &Xia, K. (2026, January). ORTCL: Towards Continual Learning of Time Series Foundation Models on Streaming Data via Orthogonal Rotation. In Proceedings of the AAAI Conference on Artificial Intelligence. 2026.

A Transferable Spatio-temporal Learning Framework for Cross-city Logistics Demand Prediction

Published in ACM SIGKDD, 2025

In logistic systems, demand prediction is an essential task providing the basis for improving the quality of terminal services, such as pick-up and delivery efficiency. However, the geographical scope of operations across multiple cities brings challenges due to the sparsity of user behavior data, hindering accurate predictions. Despite cross-city prediction methods potentially solving this problem by relying on the label of overlapping users in different cities, annotating these overlapping users is expensive. Additionally, the dynamic and diverse nature of user behaviors complicates feature transfer between cities. In this work, we define the logistics demand prediction problem as forecasting pick-up and delivery demand for zones, the smallest operational units in logistics systems, in different cities. To address the challenge, we propose TSTL, a Transferable Spatio-Temporal Learning framework for cross-city logistics prediction with sparse user data. TSTL advances existing methods from two aspects: (1) User-level invariant representation module extracts consistent user representations for overlapping and non-overlapping users across cities. (2) User-zone graph aggregation module enhances user embeddings by integrating dynamic interactions, such as logistics behaviors, into inherent user relations. Finally, the multi-city transfer module fine-tunes model parameters for city-invariant knowledge adoption and predicts future logistics demand. We implement and evaluate TSTL on one of the largest logistics systems. Extensive offline experiments and real-world deployment demonstrate the effectiveness of TSTL.

Recommended citation: Xia, K., Lin, L., Zhang, X., Wang, H., Wang, S., & He, T. (2025, August). A Transferable Spatio-temporal Learning Framework for Cross-city Logistics Demand Prediction. In Proceedings of the 31st ACM SIGKDD Conference on Knowledge Discovery and Data Mining V. 2 (pp. 5071-5082). https://dl.acm.org/doi/abs/10.1145/3711896.3737186

PATR: Periodicity-Aware Trajectory Recovery for Express System via Seq2Seq Model

Published in IEEE Globecom, 2022

The analysis of express trajectory is essential for delivery service optimization and courier management. Express trajectory consists of a large amount of community paths which is different from the trajectory of transportation tools such as taxis which run in the main road of a city. Due to the complexity of the community road networks and the energy constraint of devices, trajectories are collected under a low sampling rate and accuracy. These trajectories need to be recovered and mapped to the road networks for further analysis. Current recovery approaches utilize two-stage or end-to-end models to generate the upsampled trajectories. These methods fail to fully exploit the periodicity relation in historical data, which leads to accuracy losses for complex community road networks. In this paper, we design PATR, a periodicity-aware Seq2Seq model, to recover the couriers’ trajectories by leveraging the periodical patterns of the historical data. We conduct experimental evaluations based on real-world GPS data of JD logistics consisting of 836,959 points and 25,726 road segments, and our model outperforms the state-of-the-art baselines by reducing recovery error by 2.4%-21.9%.

Recommended citation: Zhang, X., Liang, X., Wang, H., Wang, S., & He, T. (2022, December). PATR: Periodicity-Aware Trajectory Recovery for Express System via Seq2Seq Model. In GLOBECOM 2022-2022 IEEE Global Communications Conference (pp. 486-491). IEEE. https://ieeexplore.ieee.org/abstract/document/10001476

Multi-scale Temporal Feature Fusion for Time-Limited Order Prediction

Published in China Conference on Wireless Sensor Networks, 2022

The time-limited order is a new type of real-time delivery service that platforms need to complete the order delivery with different time granularity (e.g. one day, two days, or three days). Predicting the number of time-limited orders plays an important role for real-time order delivery allocation and anomaly detection in logistics IoT scenarios. However, the impact between orders of different time granularity is complex and the contribution of the static order features is unknown. Previous order predicting methods are not suitable for time-limited orders because they do not fully consider the dependencies among orders with different time granularity. In this paper, we propose a spatial-temporal framework based on stacked long short-term memory networks (LSTM) and deep & cross network (DCN) to take the dependencies of multi-scale temporal features into account and fuse cross-domain static features effectively. In addition, we utilize a multi-head attention mechanism to model the heterogeneous strengths of different dependencies. We evaluate our model on a real-world dataset with about 400,000 orders from one of the largest logistics companies in China. The evaluation results show that the Mean Absolute Error and R2 score of our method achieve 9.407 and 0.948, outperforming state-of-the-art solutions. Download paper here

Recommended citation: Wang, J., Zhou, X., Liu, Y., Zhang, X., & Wang, S. (2022, November). Multi-scale Temporal Feature Fusion for Time-Limited Order Prediction. In China Conference on Wireless Sensor Networks (pp. 132-144). Singapore: Springer Nature Singapore. https://link.springer.com/chapter/10.1007/978-981-19-8350-4_11