TRINITY: Tradable Mobility Credits for Efficient Transportation

可交易出行信用（TMC）作为一种出行需求管理方式，近年来受到交通领域的广泛关注。在TMC计划中，监管机构最初向所有潜在的旅行者提供初始的移动信用或代币。为了使用交通系统，用户需要花费一定数量的代币，这些代币可能会随着出行方式、路线、出发时间等的选择而变化。代币可以在市场上以由代币需求和供应决定的价格进行买卖。该项目将设计、建模和评估一个名为Trinity的实时运行tmc系统。Trinity针对每个用户进行个性化设计，旨在通过对交通系统的未来预测来改善社会福利等系统级目标。这项研究有可能加速对tmc的理解和实际部署，并通过缓解拥堵、减少能源和排放，帮助交通机构和运营商实现可持续发展的长期社会目标。在该项目下开发的算法和软件将是开源和公开共享的。它们将与交通系统预测和控制平台DynaMIT集成，这将为研究人员进一步扩展科学知识提供有用的工具。该项目的教育效益包括培养研究生和博士后研究人员参与本科和研究生的教学活动和指导。具体来说，该项目追求以下目标：(1)设计并实现一个为“在线”应用量身定制的新型双层优化框架，该框架包括两个组件：通过利用交通网络的短期预测，定期（实时）确定不同移动选项的“最佳”令牌（移动信用）费率的系统级优化，以及用户级优化，将确定个性化的“最佳”移动选项菜单，以显示给每个受最佳系统级令牌收费政策约束的单个用户；(2)通过考虑用户（个人买卖决策和包含异质性的合理行为模型）和监管机构的行为，对代币市场的运营/动态进行建模；(3)进行广泛的模拟？基于现实世界网络的实验，以深入了解TMC方案的设计、用户行为和网络条件如何影响性能和市场动态（例如：如何设计令牌的分配/获取/到期；监管机构如何以及何时干预市场，如何设计令牌策略以允许优化和网络控制的可扩展性/有效性？）。Trinity系统采用复杂的基于模拟的分类运输和市场模型，将允许研究人员社区了解当代币收费、交通流量模式和市场价格一起演变时的系统行为。这是一个非常有趣的话题，但迄今为止受到的关注有限。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Tradable mobility credit (TMC) schemes as a way to manage travel demand have received significant attention in the transportation domain in recent years. In a TMC scheme, a regulator initially provides an initial endowment of mobility credits or tokens to all potential travelers. In order to use the transportation system, users need to spend a certain amount of tokens that could vary with the choice of travel mode, route, departure time etc. The tokens can be bought and sold in a market at a price that is determined by token demand and supply. This project will design, model and evaluate a system of TMCs--named Trinity--that operate in real-time. Trinity is personalized for each user and is designed to improve system-level objectives such as social welfare using future predictions of the transportation system. This study has the potential to accelerate the understanding and real-world deployment of TMCs and aid transportation agencies and operators in achieving long-term societal goals of sustainability by mitigating congestion and reducing energy and emissions. Algorithms and software developed under the project will be open-source and publically shared. They will be integrated with a transportation system prediction and control platform, DynaMIT, which will provide a useful tool for researchers to further extend the scientific knowledge. Educational benefits from the project include the training of graduate students and the involvement of postdoctoral researchers in undergraduate and graduate teaching activities and advising. Specifically, the project pursues the following goals: (1) Design and implement a novel bi-level optimization framework tailored for 'online' applications that includes two components: a system-level optimization that periodically (in real-time) determines 'optimal' token (mobility credit) rates for different mobility options by utilizing short term predictions of the transportation network, and a user-level optimization that will determine a personalized 'optimal' menu of mobility options to display to each individual user subject to the optimal system-level token charging policy; (2) Model the operation/dynamics of the token market by considering actions of the user (individual buying and selling decisions and plausible behavioral models incorporating heterogeneity) and regulator; and (3) Perform extensive simulation?based experiments on real-world networks to gain insights into how the design of the TMC schemes, user behavior, and network conditions can impact performance and market dynamics (for example: how should the allocation/acquisition/expiration of tokens be designed; how and when does the regulator intervene in the market, how should the token policies be designed to allow for scalability/effectiveness of optimization and network control?). The Trinity system, in employing complex simulation-based disaggregate transportation and market models, will allow a community of researchers to gain insights into system behavior when the token charges, traffic flow patterns and market price evolve together?a topic of immense interest which has received limited attention thus far.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.