Given an urban development plan and the historical traffic observations over the road network, the Conditional Urban Traffic Estimation problem aims to estimate the resulting traffic status prior to the deployment of the plan. This problem is of great importance to urban development and transportation management, yet is very challenging because the plan would change the local travel demands drastically and the new travel demand pattern might be unprecedented in the historical data. To tackle these challenges, we propose a novel Conditional Urban Traffic Generative Adversarial Network (Curb-GAN), which provides traffic estimations in consecutive time slots based on different (unprecedented) travel demands, thus enables urban planners to accurately evaluate urban plans before deploying them. The proposed Curb-GAN adopts and advances the conditional GAN structure through a few novel ideas: (1) dealing with various travel demands as the "conditions" and generating corresponding traffic estimations, (2) integrating dynamic convolutional layers to capture the local spatial auto-correlations along the underlying road networks, (3) employing self-attention mechanism to capture the temporal dependencies of the traffic across different time slots. Extensive experiments on two real-world spatio-temporal datasets demonstrate that our Curb-GAN outperforms major baseline methods in estimation accuracy under various conditions and can produce moremore »
This content will become publicly available on December 7, 2022
QCell: Self-optimization of Softwarized 5G Networks through Deep Q-learning
With the unprecedented rise in traffic demand and mobile subscribers, real-time fine-grained optimization frameworks are crucial for the future of cellular networks. Indeed, rigid and inflexible infrastructures are incapable of adapting to the massive amounts of data forecast for 5G networks. Network softwarization, i.e., the approach of controlling “everything” via software, endows the network with unprecedented flexibility, allowing it to run optimization and machine learning-based frame- works for flexible adaptation to current network conditions and traffic demand. This work presents QCell, a Deep Q-Network- based optimization framework for softwarized cellular networks. QCell dynamically allocates slicing and scheduling resources to the network base stations adapting to varying interference con- ditions and traffic patterns. QCell is prototyped on Colosseum, the world’s largest network emulator, and tested in a variety of network conditions and scenarios. Our experimental results show that using QCell significantly improves user’s throughput (up to 37.6%) and the size of transmission queues (up to 11.9%), decreasing service latency.
- Award ID(s):
- 1925601
- Publication Date:
- NSF-PAR ID:
- 10298727
- Journal Name:
- IEEE Globecom 2021
- Page Range or eLocation-ID:
- 1-6
- Sponsoring Org:
- National Science Foundation
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