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Bai, T., Johansson, A., Li, S., Johansson, K. H. & Mårtensson, J. (2025). A third-party platoon coordination service: Pricing under government subsidies. Asian Journal of Control, 27(1), 13-26
Open this publication in new window or tab >>A third-party platoon coordination service: Pricing under government subsidies
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2025 (English)In: Asian Journal of Control, ISSN 1561-8625, E-ISSN 1934-6093, Vol. 27, no 1, p. 13-26Article in journal (Refereed) Published
Abstract [en]

This paper models a platooning system consisting of trucks and a third-party service provider (TPSP), which performs platoon coordination, distributes the platooning profit in platoons, and charges trucks in exchange for the services. Government subsidies used to incentivize platooning are also considered. We propose a pricing rule for the TPSP, which keeps part of the platooning profit including the subsidy each time a platoon is formed. In addition, a platoon coordination solution based on the distributed model predictive control (MPC) is proposed, in which the pricing rule under government subsidies is integrated. We perform a realistic simulation over the Swedish road network to evaluate the impact of the pricing rule and subsidies on the achieved profits and fuel savings. Our results show that subsidies are an effective mean to boost fuel savings from platooning. Moreover, the simulation study indicates that high pricing corresponds to a low platooning rate of the system, as trucks' incentives for platooning decrease.

Place, publisher, year, edition, pages
Wiley, 2025
Keywords
distributed model predictive control, government subsidies, platoon coordination, pricing rules
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-360965 (URN)10.1002/asjc.3152 (DOI)001412798300004 ()2-s2.0-85163100237 (Scopus ID)
Note

QC 20250310

Available from: 2025-03-10 Created: 2025-03-10 Last updated: 2025-03-10Bibliographically approved
Bai, T., Li, Y., Johansson, K. H. & Mårtensson, J. (2024). Distributed Charging Coordination of Electric Trucks with Limited Charging Resources. In: 2024 European Control Conference, ECC 2024: . Paper presented at 2024 European Control Conference, ECC 2024, Stockholm, Sweden, Jun 25 2024 - Jun 28 2024 (pp. 2897-2902). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Distributed Charging Coordination of Electric Trucks with Limited Charging Resources
2024 (English)In: 2024 European Control Conference, ECC 2024, Institute of Electrical and Electronics Engineers (IEEE) , 2024, p. 2897-2902Conference paper, Published paper (Refereed)
Abstract [en]

Electric trucks usually need to charge their batteries during long-range delivery missions, and the charging times are often nontrivial. As charging resources are limited, waiting times for some trucks can be prolonged at certain stations. To facilitate the efficient operation of electric trucks, we propose a distributed charging coordination framework. Within the scheme, the charging stations provide waiting estimates to incoming trucks upon request and assign charging ports according to the first-come, first-served rule. Based on the updated information, the individual trucks compute where and how long to charge whenever approaching a charging station in order to complete their delivery missions timely and cost-effectively. We perform empirical studies for trucks traveling over the Swedish road network and compare our scheme with the one where charging plans are computed offline, assuming unlimited charging facilities. It is shown that the proposed scheme outperforms the offline approach at the expense of little communication overhead.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2024
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:kth:diva-351930 (URN)10.23919/ECC64448.2024.10590837 (DOI)001290216502108 ()2-s2.0-85200596068 (Scopus ID)
Conference
2024 European Control Conference, ECC 2024, Stockholm, Sweden, Jun 25 2024 - Jun 28 2024
Note

QC 20250428

Available from: 2024-08-19 Created: 2024-08-19 Last updated: 2025-04-28Bibliographically approved
Jiang, L., Li, Y. & Bai, T. (2024). DSFPAP-Net: Deeper and Stronger Feature Path Aggregation Pyramid Network for Object Detection in Remote Sensing Images. IEEE Geoscience and Remote Sensing Letters, 21, Article ID 6010505.
Open this publication in new window or tab >>DSFPAP-Net: Deeper and Stronger Feature Path Aggregation Pyramid Network for Object Detection in Remote Sensing Images
2024 (English)In: IEEE Geoscience and Remote Sensing Letters, ISSN 1545-598X, E-ISSN 1558-0571, Vol. 21, article id 6010505Article in journal (Refereed) Published
Abstract [en]

Rapid detection of small objects in remote sensing (RS) images is crucial for intelligence acquisition, for instance, enemy ship detection. Instead of employing images with high resolution, low-resolution images of the same size typically cover a wider area and thus facilitate efficient object detection. However, accurately detecting small objects in such images remains a challenge due to their limited visual information and the difficulty in distinguishing them from the background. To address this issue, we propose a small object detection method called the deeper and stronger feature path aggregation pyramid network (DSFPAP-Net) for low-resolution RS images. First, our approach involves designing aggregation networks with deeper paths and utilizing feature layers closer to the shallow layers to enhance the acquisition of information about small objects. Second, to enhance the network's focus on small objects, we propose a resolution-adjustable 3-D weighted attention (RA3-DWA) mechanism. This mechanism enables independent learning of spatial feature information and assigns 3-D weights specifically to small objects, resulting in improved detection accuracy for small objects. Finally, we propose the Fast-EIoU loss function to accelerate the regression of the model boundary. This loss function assigns an acceleration factor to the length loss and width loss, respectively, thereby improving the detection accuracy of small objects. Experiments on Levir-Ship and DOTA demonstrate the effectiveness and efficiency of the proposed method. Compared to the baseline YOLOv5, our method has improved the average detection accuracy of the Levir-Ship dataset by 6.7% (reaching up to 82.6%) and the accuracy of the DOTA dataset by 6.4% (reaching up to 73.7%).

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2024
Keywords
Remote sensing, Feature extraction, Image resolution, YOLO, Semantics, Kernel, Convolution, 3-D attention, fast-EIoU loss function, low-resolution remote sensing images, small objects
National Category
Computer graphics and computer vision
Identifiers
urn:nbn:se:kth:diva-350124 (URN)10.1109/LGRS.2024.3398727 (DOI)001248303400019 ()2-s2.0-85192789805 (Scopus ID)
Note

QC 20240708

Available from: 2024-07-08 Created: 2024-07-08 Last updated: 2025-02-07Bibliographically approved
Ou, J., Jiang, L., Bai, T., Zhan, P., Liu, R. & Xiao, H. (2024). ResTransUnet: An effective network combined with Transformer and U-Net for liver segmentation in CT scans. Computers in Biology and Medicine, 177, Article ID 108625.
Open this publication in new window or tab >>ResTransUnet: An effective network combined with Transformer and U-Net for liver segmentation in CT scans
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2024 (English)In: Computers in Biology and Medicine, ISSN 0010-4825, E-ISSN 1879-0534, Vol. 177, article id 108625Article in journal (Refereed) Published
Abstract [en]

Liver segmentation is a fundamental prerequisite for the diagnosis and surgical planning of hepatocellular carcinoma. Traditionally, the liver contour is drawn manually by radiologists using a slice-by-slice method. However, this process is time-consuming and error-prone, depending on the radiologist's experience. In this paper, we propose a new end-to-end automatic liver segmentation framework, named ResTransUNet, which exploits the transformer's ability to capture global context for remote interactions and spatial relationships, as well as the excellent performance of the original U-Net architecture. The main contribution of this paper lies in proposing a novel fusion network that combines Unet and Transformer architectures. In the encoding structure, a dual-path approach is utilized, where features are extracted separately using both convolutional neural networks (CNNs) and Transformer networks. Additionally, an effective feature enhancement unit is designed to transfer the global features extracted by the Transformer network to the CNN for feature enhancement. This model aims to address the drawbacks of traditional Unet-based methods, such as feature loss during encoding and poor capture of global features. Moreover, it avoids the disadvantages of pure Transformer models, which suffer from large parameter sizes and high computational complexity. The experimental results on the LiTS2017 dataset demonstrate remarkable performance for our proposed model, with Dice coefficients, volumetric overlap error (VOE), and relative volume difference (RVD) values for liver segmentation reaching 0.9535, 0.0804, and −0.0007, respectively. Furthermore, to further validate the model's generalization capability, we conducted tests on the 3Dircadb, Chaos, and Sliver07 datasets. The experimental results demonstrate that the proposed method outperforms other closely related models with higher liver segmentation accuracy. In addition, significant improvements can be achieved by applying our method when handling liver segmentation with small and discontinuous liver regions, as well as blurred liver boundaries. The code is available at the website: https://github.com/Jouiry/ResTransUNet.

Place, publisher, year, edition, pages
Elsevier BV, 2024
Keywords
Deep learning, Liver segmentation, Medical imaging processing, Transformers
National Category
Medical Imaging
Identifiers
urn:nbn:se:kth:diva-347636 (URN)10.1016/j.compbiomed.2024.108625 (DOI)38823365 (PubMedID)2-s2.0-85194911330 (Scopus ID)
Note

QC 20240613

Available from: 2024-06-12 Created: 2024-06-12 Last updated: 2025-02-09Bibliographically approved
Bai, T., Johansson, A., Johansson, K. H. & Mårtensson, J. (2023). Large-Scale Multi-Fleet Platoon Coordination: A Dynamic Programming Approach. IEEE transactions on intelligent transportation systems (Print), 24(12), 14427-14442
Open this publication in new window or tab >>Large-Scale Multi-Fleet Platoon Coordination: A Dynamic Programming Approach
2023 (English)In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 24, no 12, p. 14427-14442Article in journal (Refereed) Published
Abstract [en]

Truck platooning is a promising technology that enables trucks to travel in formations with small inter-vehicle distances for improved aerodynamics and fuel economy. The real-world transportation system includes a vast number of trucks owned by different fleet owners, for example, carriers. To fully exploit the benefits of platooning, efficient dispatching strategies that facilitate the platoon formations across fleets are required. This paper presents a distributed framework for addressing multi-fleet platoon coordination in large transportation networks, where each truck has a fixed route and aims to maximize its own fleet's platooning profit by scheduling its waiting times at hubs. The waiting time scheduling problem of individual trucks is formulated as a distributed optimal control problem with continuous decision space and a reward function that takes non-zero values only at discrete points. By suitably discretizing the decision and state spaces, we show that the problem can be solved exactly by dynamic programming, without loss of optimality. Finally, a realistic simulation study is conducted over the Swedish road network with 5,000 trucks to evaluate the profit and efficiency of the approach. The simulation study shows that, compared to single-fleet platooning, multi-fleet platooning provided by our method achieves around 15 times higher monetary profit and increases the CO2 emission reductions from 0.4% to 5.5%. In addition, it shows that the developed approach can be carried out in real-time and thus is suitable for platoon coordination in large transportation systems.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2023
Keywords
dynamic programming, Large-scale systems, multi-fleet platoon coordination, truck platooning
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-348233 (URN)10.1109/TITS.2023.3298564 (DOI)001047503000001 ()2-s2.0-85166744495 (Scopus ID)
Note

QC 20240620

Available from: 2024-06-20 Created: 2024-06-20 Last updated: 2024-06-20Bibliographically approved
Johansson, A., Bai, T., Johansson, K. H. & Mårtensson, J. (2023). Platoon Cooperation Across Carriers: From System Architecture to Coordination. IEEE Intelligent Transportation Systems Magazine, 15(3), 132-144
Open this publication in new window or tab >>Platoon Cooperation Across Carriers: From System Architecture to Coordination
2023 (English)In: IEEE Intelligent Transportation Systems Magazine, ISSN 1939-1390, Vol. 15, no 3, p. 132-144Article in journal (Refereed) Published
Abstract [en]

Truck platooning is a well-studied technology that has the potential to reduce both the environmental impact and operational costs of trucks. The technology has matured over the last 20 years, and the commercial rollout of platooning is approaching. Cooperation across carriers is essential for the viability of platooning; otherwise, many platooning opportunities are lost. We first present a cross-carrier platooning system architecture in which many carriers cooperate in forming platoons through a platoon-hailing service. Then, we present a cross-carrier platoon coordination approach in which each carrier optimizes its platooning plans according to the predicted plans of other carriers. A profit-sharing mechanism to even out the platooning profit in each platoon is embedded in the platoon coordination approach. Finally, a simulation study over the Swedish road network is performed to evaluate the potential of platooning under realistic conditions. The simulation study shows that the energy consumption of trucks in Sweden can be reduced by 5.4% due to platooning and that cooperation across carriers is essential to achieve significant platooning benefits.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2023
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-330106 (URN)10.1109/MITS.2022.3219997 (DOI)000899945500001 ()2-s2.0-85144749356 (Scopus ID)
Note

QC 20230626

Available from: 2023-06-26 Created: 2023-06-26 Last updated: 2023-06-26Bibliographically approved
Jiang, L., Ou, J., Liu, R., Zou, Y., Xie, T., Xiao, H. & Bai, T. (2023). RMAU-Net: Residual Multi-Scale Attention U-Net For liver and tumor segmentation in CT images. Computers in Biology and Medicine, 158, Article ID 106838.
Open this publication in new window or tab >>RMAU-Net: Residual Multi-Scale Attention U-Net For liver and tumor segmentation in CT images
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2023 (English)In: Computers in Biology and Medicine, ISSN 0010-4825, E-ISSN 1879-0534, Vol. 158, article id 106838Article in journal (Refereed) Published
Abstract [en]

Liver cancer is one of the leading causes of cancer-related deaths worldwide. Automatic liver and tumor segmentation are of great value in clinical practice as they can reduce surgeons' workload and increase the probability of success in surgery. Liver and tumor segmentation is a challenging task because of the different sizes, shapes, blurred boundaries of livers and lesions, and low-intensity contrast between organs within patients. To address the problem of fuzzy livers and small tumors, we propose a novel Residual Multi-scale Attention U-Net (RMAU-Net) for liver and tumor segmentation by introducing two modules, i.e., Res-SE-Block and MAB. The Res-SE-Block can mitigate the problem of gradient disappearance by residual connection and enhance the quality of representations by explicitly modeling the interdependencies and feature recalibration between the channels of features. The MAB can exploit rich multi-scale feature information and capture inter -channel and inter-spatial relationships of features simultaneously. In addition, a hybrid loss function, that combines focal loss and dice loss, is designed to improve segmentation accuracy and speed up convergence. We evaluated the proposed method on two publicly available datasets, i.e., LiTS and 3D-IRCADb. Our proposed method achieved better performance than the other state-of-the-art methods, with dice scores of 0.9552 and 0.9697 for LiTS and 3D-IRCABb liver segmentation, and dice scores of 0.7616 and 0.8307 for LiTS and 3D-IRCABb liver tumor segmentation.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
Liver and tumor segmentation, Multi-scale feature, Attention mechanism, Deep learning, Medical imaging
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:kth:diva-326885 (URN)10.1016/j.compbiomed.2023.106838 (DOI)000974938000001 ()37030263 (PubMedID)2-s2.0-85151674998 (Scopus ID)
Note

QC 20230515

Available from: 2023-05-15 Created: 2023-05-15 Last updated: 2023-05-15Bibliographically approved
Bai, T., Li, Y., Johansson, K. H. & Mårtensson, J. (2023). Rollout-Based Charging Strategy for Electric Trucks With Hours-of-Service Regulations. IEEE Control Systems Letters, 7, 2167-2172
Open this publication in new window or tab >>Rollout-Based Charging Strategy for Electric Trucks With Hours-of-Service Regulations
2023 (English)In: IEEE Control Systems Letters, E-ISSN 2475-1456, Vol. 7, p. 2167-2172Article in journal (Refereed) Published
Abstract [en]

Freight drivers of electric trucks need to design charging strategies for where and how long to recharge the truck in order to complete delivery missions on time. Moreover, the charging strategies should be aligned with drivers' driving and rest time regulations, known as hours-of-service (HoS) regulations. This letter studies the optimal charging problems of electric trucks with delivery deadlines under HoS constraints. We assume that a collection of charging and rest stations is given along a pre-planned route with known detours and that the problem data are deterministic. The goal is to minimize the total cost associated with the charging and rest decisions during the entire trip. This problem is formulated as a mixed integer program with bilinear constraints, resulting in a high computational load when applying exact solution approaches. To obtain real-time solutions, we develop a rollout-based approximate scheme, which scales linearly with the number of stations while offering solid performance guarantees. We perform simulation studies over the Swedish road network based on realistic truck data. The results show that our rollout-based approach provides near-optimal solutions to the problem in various conditions while cutting the computational time drastically.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2023
Keywords
Charging strategy, electric trucks, HoS regulations, rollout
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-332184 (URN)10.1109/LCSYS.2023.3285137 (DOI)001021356700013 ()2-s2.0-85162711815 (Scopus ID)
Note

QC 20230721

Available from: 2023-07-21 Created: 2023-07-21 Last updated: 2023-07-21Bibliographically approved
Bai, T., Johansson, A., Li, S., Johansson, K. H. & Mårtensson, J. (2022). A Pricing Rule for Third-Party Platoon Coordination Service Provider. In: ASCC 2022 - 2022 13th Asian Control Conference, Proceedings: . Paper presented at 13th Asian Control Conference, ASCC 2022, 4 May 2022 through 7 May 2022 (pp. 2344-2349). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>A Pricing Rule for Third-Party Platoon Coordination Service Provider
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2022 (English)In: ASCC 2022 - 2022 13th Asian Control Conference, Proceedings, Institute of Electrical and Electronics Engineers (IEEE) , 2022, p. 2344-2349Conference paper, Published paper (Refereed)
Abstract [en]

We model a platooning system including trucks and a third-party service provider that performs platoon coordination, distributes the platooning profit within platoons, and charges the trucks in exchange for its services. This paper studies one class of pricing rules, where the third-party service provider keeps part of the platooning profit each time a platoon is formed. Furthermore, we propose a platoon coordination solution based on distributed model predictive control in which the pricing rule is integrated. To evaluate the effect of the pricing on the platooning system, we perform a simulation over the Swedish road network. The simulation shows that the platooning rate and profit highly depend on the pricing. This suggests that pricing needs to be set carefully to obtain a satisfactory platooning system in the future.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2022
Keywords
distributed model predictive control, Platoon coordination, pricing rules, profit-sharing, Automobiles, Costs, Model predictive control, Trucks, Wages, ITS Services, Profits sharing, Road network, Service provider, Swedishs, Third parties, Third-party service providers, Profitability
National Category
Transport Systems and Logistics
Identifiers
urn:nbn:se:kth:diva-326673 (URN)10.23919/ASCC56756.2022.9828062 (DOI)2-s2.0-85135613642 (Scopus ID)
Conference
13th Asian Control Conference, ASCC 2022, 4 May 2022 through 7 May 2022
Note

QC 20230510

Available from: 2023-05-10 Created: 2023-05-10 Last updated: 2023-05-10Bibliographically approved
Bai, T., Johansson, A., Johansson, K. H. & Mårtensson, J. (2022). Approximate Dynamic Programming for Platoon Coordination under Hours-of-Service Regulations. In: 2022 IEEE 61ST CONFERENCE ON DECISION AND CONTROL (CDC): . Paper presented at IEEE 61st Conference on Decision and Control (CDC), DEC 06-09, 2022, Cancun, MEXICO (pp. 7663-7669). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Approximate Dynamic Programming for Platoon Coordination under Hours-of-Service Regulations
2022 (English)In: 2022 IEEE 61ST CONFERENCE ON DECISION AND CONTROL (CDC), Institute of Electrical and Electronics Engineers (IEEE) , 2022, p. 7663-7669Conference paper, Published paper (Refereed)
Abstract [en]

Truck drivers are required to stop and rest with a certain regularity according to the driving and rest time regulations, also called Hours-of-Service (HoS) regulations. This paper studies the problem of optimally forming platoons when considering realistic HoS regulations. In our problem, trucks have fixed routes in a transportation network and can wait at hubs along their routes to form platoons with others while fulfilling the driving and rest time constraints. We propose a distributed decision-making scheme where each truck controls its waiting times at hubs based on the predicted schedules of others. The decoupling of trucks' decision-makings contributes to an approximate dynamic programming approach for platoon coordination under HoS regulations. Finally, we perform a simulation over the Swedish road network with one thousand trucks to evaluate the achieved platooning benefits under the HoS regulations in the European Union (EU). The simulation results show that, on average, trucks drive in platoons for 37 % of their routes if each truck is allowed to be delayed for 5 % of its total travel time. If trucks are not allowed to be delayed, they drive in platoons for 12 % of their routes.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2022
Series
IEEE Conference on Decision and Control, ISSN 0743-1546
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-326397 (URN)10.1109/CDC51059.2022.9993403 (DOI)000948128106062 ()2-s2.0-85146971147 (Scopus ID)
Conference
IEEE 61st Conference on Decision and Control (CDC), DEC 06-09, 2022, Cancun, MEXICO
Note

QC 20230502

Available from: 2023-05-02 Created: 2023-05-02 Last updated: 2023-05-02Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-9488-9143

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