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Reliable port services are key to maritime freight transport system performance. These systems are vulnerable to disasters of anthropogenic or natural cause, which can significantly impact port capacity, handling times and overall system performance. To improve resilience of individual ports, strategies involving capacity sharing and protective cross-port investments through coalition formation are proposed. This collaborative port protection and investment approach to improve individual and system-level port resilience is formulated as an Equilibrium Problem with Equilibrium Constraints. That is, the program is bi-level with multiple players in the upper level and a common liner shipping problem in the lower level. Its solution is obtained at a Nash equilibrium wherein no port stakeholder can achieve better performance by unilaterally changing its investment plan. A Stackelberg equilibrium between upper and lower levels infers that best investment decisions are made given competition between ports and the market’s response to improvements. The benefits of regional coalitions in this co-opetitive (competitive and collaborative) environment in terms of port and system resilience, port- and system-level demand fulfilment rates and return on investment are investigated from multiple perspectives, including the perspectives of shippers, port owners and the larger shipping network. With insights gained through study of the proposed coalition policies, this work aims to facilitate port authorities in making decisions on port capacity expansion, infrastructure investment and forming strategic partnerships. Shipping companies may also take into consideration the ability of a port to provide service under disruption events when choosing which ports to include in their service loops.
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An updatable and comprehensive global cargo maritime network and strategic seaborne cargo routing model for global containerized and bulk vessel flow estimation 2021
{"Abstract":["The global maritime system provides the backbone of logistics operations for global supply chains and international trade. This paper aims to develop a unifying global network representation and strategic, system-wide decision model, the Strategic Cargo Routing Model, incorporating both liner and bulk shipping markets to estimate real-world traffic flows and study traffic patterns at the global scale. Specifically, taking a shipper's perspective, containerized and bulk movements are jointly modelled within a mixed-integer linear program that includes inbound, outbound, and transshipment cargo flows at ports. An iterative approach that combines heuristic Gradient Descent and Relax-and-Fix Decomposition methods is proposed for the calibration and solution of the Strategic Cargo Routing Model over a proposed joint liner and bulk services Global Cargo Shipping Network representation. The Global Cargo Shipping Network contains 161 seaports covering 52 countries. It is created from updatable, publicly available, data sources, and all data needed for the network representation are made available. Sufficient network details, as well as data sources and methods for extracting needed inputs, are given to allow others to use and update the network. Using the developed maritime network, mathematical model and calibration-solution methodology, 2018 global maritime traffic flow patterns were estimated. The estimates were found to achieve a 91% fit overall to real-world average annual port throughputs. This strategic model provides support to evaluate future, real-world, worldwide changes, such as increased seaborne trade demand, new routes, shipping infrastructure expansion, and transport policies.\n * In the data subnetwork X=(0, 1, 2) refers to containerized cargo, liquid bulk and dry bulk respectively. for example, flowX shows flows in subnetworks of X=(0, 1, 2) accordingly. portThrouX.csv shows port throughputs in subnetworks of X=(0, 1, 2) accordingly.\n **In the uploaded data, the files starting with input... means they are inputs for the model, and other files are outputs.\n **Note that the uploaded materials can be used based on the uploaded paper "Wenjie Li, Ralph Pundt and Elise Miller-Hooks. (2021). An updatable and comprehensive global cargo maritime network and strategic seaborne cargo routing model for global containerized and bulk vessel flow estimation 2021.""]}
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- Award ID(s):
- 1927785
- PAR ID:
- 10639408
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Global cargo shipping Maritime networks Trade Liner shipping Bulk shipping Trade routes
- Format(s):
- Medium: X Other: text/xml
- Location:
- Arctic Data Center
- Institution:
- NSF
- Sponsoring Org:
- National Science Foundation
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