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This study focuses on relay transport carriers (RTCs) that contract with hub providers to lease hub capacity and employ relay transportation via hubs. It enables long-haul freight shipments to be transported by multiple short-haul drivers commuting between fixed-base hubs, promoting a driver-friendly approach. Inspired by Physical Internet, our paper addresses the multi-period capacity planning of logistic hubs within relay networks, accounting for uncertainty in demand and travel times. We model the problem as a two-stage stochastic optimization to determine the dynamic logistic hub throughput capacities for each planning period, ensuring the fulfillment of logistic demand while simultaneously minimizing both hub and transportation costs. This optimization problem falls within the NP-hard complexity class. To alleviate the inherent challenges in solving this problem, we employ a scenario reduction algorithm based on the fast forward selection (FFS) method to reduce computational effort while preserving approximation quality. Experiments with an automotive-delivery RTC in the Southeastern US demonstrate that our capacity planning model enables RTCs to proactively respond to dynamic circumstances, curtail avoidable expenditures, and enhance overall logistical efficiency.

With the development of e-commerce during the Covid-19 pandemic, one of the major challenges for many parcel logistics companies is to design reliable and flexible scheduling algorithms to meet uncertainties of parcel arrivals as well as manpower supplies in logistic hubs, especially for those depending on workforce greatly. Currently, most labor scheduling is periodic and limited to single facility, thus the number of required workers in each hub is constrained to meet the peak demand with high variance. We approach this challenge, recognizing that not only workforce schedules but also working locations could be dynamically optimized by developing a dynamic workforce scheduling and relocation system, fed from updated data with sensors and dynamically updated hub arrival demand predictions. In this paper, we propose novel reactive scheduling heuristics to dynamically match predicted arrivals with shifts at hyperconnected parcel logistics hubs. Dynamic scheduling and allocation mechanisms are carried out dynamically during delivery periods to spatiotemporally adjust the available workforce. We also include penalty costs to keep parcels sorted in time and scheduling adjustments are made in advance to allow sufficient time for crew planning. To assess the proposed methods, we conduct comprehensive case studies based on real-world parcel logistic networks of a logistic company in China. The results show that our proposed approach can significantly outperform traditional workforce scheduling strategies in hubs with limited computation time.

Modern logistics systems worldwide are facing unprecedented challenges due to the explosive growth of e-commerce, driving the need for resilient systems to tackle problems such as vulnerable supplies, volatile demands, and fragile transportation networks. Motivated by the innovative concept of the Physical Internet, this paper focuses on resilient capacity deployment of open-access logistics hubs in hyperconnected transportation under demand uncertainty and geographical disruptions. We propose a two-stage stochastic optimization model, aiming to smartly deploy the hub capacity to achieve delivery timeliness, high consolidation and network resilience while minimizing hub set-up budget and truck fleet cost. Four optimal hub network configurations are derived by applying scenarios at four stress testing levels into the optimization model, including deterministic demands without hub disruptions, deterministic demands with hub disruptions, stochastic demands without hub disruptions as well as stochastic demands with hub disruptions. To test the performances of different optimal networks, a simulation-based study is then performed over an automotive delivery-to-dealer network and dataset in the Southeast US region. Our results demonstrate the key impacts of various uncertainties on hub capacity deployment in terms of capacity configuration distribution, network resilience, delivery timeliness, and cost-effectiveness. Overall, this study provides a reliable network capacity deployment approach with persistent and sustainable economic and social performances in hyperconnected networks, and the results validate the relationship between capacity deployment and network resilience under different types of uncertainties.

Hyperconnected relay transportation enables using a relay system of short-haul drivers to deliver long-haul shipments collectively, which helps address root causes of trucker shortage issues by transforming working conditions with potentials of daily returning home, accessing consistent schedules, and facilitating load matching. This paper investigates hyperconnected relay transportation as a sustainable solution to trucker shortage issues through a logistics platform. We propose a two-stage programming model to optimize consistent working schedules for short-haul drivers while minimizing transportation costs. The first stage involves opening services and contracting truckers under demand uncertainty, where each service has a service route and approximate service schedules adhering to USA federal short-haul hour-of-service regulations. The second stage assigns hauling capacities to open services and manages commodity shipping or outsourcing given the demand realization. We extend the model formulation to account for various operational patterns (e.g., freight loading and unloading or hauler swapping) and schedule consistency requirements (e.g., weekly or daily consistency). A scenario-based approach is employed to solve the model for a case study of automotive delivery in the Southeast USA region. The experimental results validate the proposed approach, and further explore the impact of stochastic demands, operational patterns, consistent schedules, and hauling capacities on hyperconnected service network design. This research aims to offer practical guidance to practitioners in the trucking industry.

In this paper, we attempt to detect an inflection or change-point resulting from the Covid-19 pandemic on supply chain data received from a large furniture company. To accomplish this, we utilize a modified CUSUM (Cumulative Sum) procedure on the company's spatial-temporal order data as well as a GLR (Generalized Likelihood Ratio) based method. We model the order data using the Hawkes Process Network, a multi-dimensional self and mutually exciting point process, by discretizing the spatial data and treating each order as an event that has a corresponding node and time. We apply the methodologies on the company's most ordered item on a national scale and perform a deep dive into a single state. Because the item was ordered infrequently in the state compared to the nation, this approach allows us to show efficacy upon different degrees of data sparsity. Furthermore, it showcases use potential across differing levels of spatial detail., Comment: Accepted to AAAI 2023 Workshop on Graphs and more Complex structures for Learning and Reasoning

The Physical Internet (PI) puts high emphasis on enabling logistics to reliably perform at the speed mandated by and promised to customers, and to do so efficiently and sustainably. To do so, goods to be moved are encapsulated in modular containers and these are flowed from hub to hub in relay mode. At each hub, PI enables fast and efficient dynamic consolidation of sets of containers to be shipped together to next hubs. Each consolidated set is assigned to an appropriate vehicle so to enact the targeted transport. In this paper, we address the case where transportation service providers are available to provide vehicles and trailers of distinct dimensions on demand according to openly agreed and/or contracted terms. We describe the essence of such terms, notably relative to expected frequency distribution of transport requests, and expectations about time between request and arrival at hub. In such a context, we introduce rigorous generic protocols that can be applied at each hub so as to dynamically generate consolidation sets of modular containers and requests for on-demand transportation services, in an efficient, resilient, and sustainable way ensuring reliable pickup and delivery within the promised time windows. We demonstrate the performance of such protocols using a simulation-based experiment for a national intercity express parcel logistic network. We finally provide conclusive remarks and promising avenues for field implementation and further research., Comment: IPIC 2021 International Physical Internet Conference

In high-speed hyperconnected parcel logistics, intermediate hubs play a critical role in reaching economies of scale through consolidating disperse flows of goods. However, resorting small-size parcels at every hub is resource-intensive and can increase hubs' workload and parcels' total travel time. Such resorting can be reduced by smart containerized consolidation, encapsulating together parcels sharing service level and a subsequent destination. In this study, we introduce an optimization model enabling to assess the impact of such consolidation in reducing the expected total pickup-to-delivery times over a parcel logistic network and its consequences on urban logistic operations sustainability. We provide empirical results for a synthetic urban environment, contrasting consolidation performance over different operational and tactical capabilities, network configurations and demand patterns.

Last-mile logistics is regarded as an essential yet highly expensive component of parcel logistics. In dense urban environments, this is partially caused by inherent inefficiencies due to traffic congestion and the disparity and accessibility of customer locations. In parcel logistics, access hubs are facilities supporting relay-based last-mile activities by offering temporary storage locations enabling the decoupling of last-mile activities from the rest of the urban distribution chain. This paper focuses on a novel tactical problem: the geographically dynamic deployment of pooled relocatable storage capacity modules in an urban parcel network operating under space-time uncertainty. In particular, it proposes a two-stage stochastic optimization model for the access hub dynamic pooled capacity deployment problem with synchronization of underlying operations through travel time estimates, and a solution approach based on a rolling horizon algorithm with lookahead and a benders decomposition able to solve large scale instances of a real-sized megacity. Numerical results, inspired by the case of a large parcel express carrier, are provided to evaluate the computational performance of the proposed approach and suggest up to 28% last-mile cost savings and 26% capacity savings compared to a static capacity deployment strategy., Comment: 36 pages, 10 figures

The Physical Internet and hyperconnected logistics concepts promise an open, more efficient and environmentally friendly supply chain for goods. Blockchain and Internet of Things technologies are increasingly regarded as main enablers of improvements in this domain. We describe how blockchain and smart contracts present the potential of being applied to hyperconnected logistics by showing a concrete example of its implementation., Comment: 8 pages, accepted for publication in IT Professional