Papers › Solving Traffic4Cast Competition with U-Net and Temporal Domain Adaptation

Solving Traffic4Cast Competition with U-Net and Temporal Domain Adaptation

5 Nov 2021arXiv:2111.03421archive 2025-07-28

Vsevolod Konyakhin, Nina Lukashina, Aleksei Shpilman

In this technical report, we present our solution to the Traffic4Cast 2021 Core Challenge, in which participants were asked to develop algorithms for predicting a traffic state 60 minutes ahead, based on the information from the previous hour, in 4 different cities. In contrast to the previously held competitions, this year's challenge focuses on the temporal domain shift in traffic due to the COVID-19 pandemic. Following the past success of U-Net, we utilize it for predicting future traffic maps. Additionally, we explore the usage of pre-trained encoders such as DenseNet and EfficientNet and employ multiple domain adaptation techniques to fight the domain shift. Our solution has ranked third in the final competition. The code is available at https://github.com/jbr-ai-labs/traffic4cast-2021.

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Tasks

Domain Adaptation

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Methods

1x1 ConvolutionAverage PoolingBatch NormalizationConcatenated Skip ConnectionConvolutionDense BlockDense ConnectionsDepthwise ConvolutionDepthwise Separable ConvolutionDropoutGlobal Average PoolingInverted Residual BlockKaiming InitializationMax PoolingPointwise ConvolutionRMSPropReLUSigmoid ActivationSoftmaxSqueeze-and-Excitation BlockU-Net

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