Maritime Networks Research Articles

The Christian Seas of Kyushu: How Local Maritime Networks Facilitated the Introduction of Catholicism to Japan in the Mid-Sixteenth Century

Using sources in both Japanese and Portuguese, this article examines how maritime connections on the island of Kyushu facilitated the spread of Christianity there during the Jesuit mission to Japan in the mid-sixteenth century. Part I builds upon recent Japanese-language scholarship on the prevalence of maritime activity and transportation on Kyushu and highlights the importance of so-called “sea peoples” for individual daimyo (regional lords) who ruled the island. Part II reveals how the first Jesuits, such as Francis Xavier, used preexisting maritime routes to missionize and founded new Christian communities along the coasts of Kyushu. Many Japanese Christians in these communities had expertise in maritime matters, which proved useful for transporting missionaries, going to church, fleeing persecution, and providing mutual assistance in times of need. In examining how local maritime networks and “sea peoples” facilitated missionization in Japan, we gain greater insight into how Christianity spread globally during the period.

Theory-Based Studies of Maritime Networks: A Literature Review

This article reviews the literature regarding maritime networks, including identifying the essential articles and authors and suggesting a categorization of associated topics. Network theory in logistics demonstrates strategic information about and competitive advantages of maritime transport between regions. We analyzed 145 technical/scientific studies of maritime networks, including articles, theses, patents, dissertations, and conference proceedings. After defining the inclusion and exclusion criteria, we selected 103 technical and scientific studies, whose analysis allowed us to suggest six categories of interest: Ports, Economy, Containerized Cargo, Maritime Safety, Clusters, and Technological Solutions and Innovations.

Challenges of Managing Maritime Cultural Heritage in Asia in the Face of Climate Change

Changing weather patterns, increasing frequency and intensity of natural hazards, and rising sea levels associated with global climate change have the potential to threaten cultural heritage sites worldwide. This is especially the case for maritime heritage sites located in the low-lying coastal and delta regions of Asia. Maritime heritage can reflect both highly localized cultural products based on the coupling of people and maritime environments and the historic footprints of complex maritime networks that connect people, ideas, and material over vast distances, creating unique cultural spheres. Furthermore, maritime heritage sites potentially serve as or contain records of how past societies have been impacted by and adapted to past environmental stress. Therefore, their degradation threatens local/regional/global cultural patrimony as well as evidence of human resilience and fragility in the face of environmental change. This makes a strong case for urgent preservation. However, the possible damage caused by climate change and the scale of vulnerable maritime heritage pose seemingly insurmountable challenges. In this paper, we present the ways in which maritime heritage sites across Asia are vulnerable to environmental stresses, such as changing sea levels, coastal erosion, flooding, and storm surges. Our objective is to draw upon our experience documenting endangered cultural heritage across South and Southeast Asia to illustrate that there are unique conceptual and practical characteristics of maritime heritage that complicate effective management and conservation efforts on the scale required to prevent massive loss by climate change. We conclude by stressing the need to reconceptualize debates about the custody and stewardship of maritime heritage and the urgency of employing a wide range of innovative preservation solutions to ensure maritime patrimony is not lost to the rising tides.

Exploring the vulnerability of transportation networks by entropy: A case study of Asia–Europe maritime transportation network

With the rise of global trade, maritime transportation networks have become an indispensable element of logistics networks. Approximately 80% of the global trade volume is transported by sea with the maritime logistics network fueling global economic integration. Due to the uncertainty of the transportation process and the impact of accidents, the reliability analysis of the logistics network is a topic of immense interest. In this paper, we propose an original and novel model to quantitatively analyze the vulnerability of the maritime logistics network by considering the importance of each port in the network. Three centrality measures that consider different topology information of the network are used in this paper to identify the importance of ports. Different information about the network is considered through the joint entropy and the multiscale factor q to evaluate the vulnerability of the logistics network. The Asia–Europe maritime transportation network serves as a real-world example to demonstrate the effectiveness and applicability of our proposed model. The experimental results suggest that the performance of the maritime network is closely related to the heterogeneity of the connectivity pattern and the process of decentralization can reduce the vulnerability of the maritime network.

Evaluation of international maritime network configuration and impact of port cooperation on port hierarchy

The objective of this study is to evaluate the impact of port cooperation on port hierarchy based on network analysis. Specifically, several complex network measures and link predictions using graph embedding are applied. Container ports have intensified the competition for higher positions in the port hierarchy because ports in the higher port hierarchy contribute to the economic development of port regions as the central point of container cargo trade. In this competitive situation, ports, especially those in proximity, build cooperative relationships to achieve higher competitiveness through synergy, such as economies of scale. We analyze the hierarchy of the aggregated Hanshin port (Kobe and Osaka, Japan) in the Japanese cargo network compared to a strong competitor, the Busan port (Korea). We find that building cooperative relationships contributes to a higher position in the port hierarchy and affects the network configuration, such as creating a higher interconnection of ports as a community structure. However, cooperation alone does not produce a higher position in the port hierarchy than a strong competitor. This study can assist policymakers engaged in port management in attaining higher positions in the port hierarchy through port cooperation. In particular, the results are valuable in areas with network configurations similar to the Japanese cargo network, which have nearby dominant hub ports, such as Busan.

Vietnam's Maritime Shipping Ports: Using Data-Driven Model Analysis to Determine Connectivity and Networking

Hu, Z.-H.; Zheng, Y.-X., and Hu, J.-J., 2022. Vietnam's maritime shipping ports: Using data-driven model analysis to determine connectivity and networking. Journal of Coastal Research, 38(3), 639–653. Coconut Creek (Florida), ISSN 0749-0208. Vietnam is a typical coastal country bordering China, Laos, and Cambodia that possesses numerous seaborne transport facilities along the coast and two main river deltas (the Mekong River Delta and Red River Delta). Vietnam's ports and shipping flows were incorporated into a maritime network model. Vietnam's coast is on the Pacific Ocean, so the clustering method is a good way to formulate and investigate the maritime network. On the land side facing Laos and bordering China and Cambodia, Vietnam's maritime network can provide gateways for Laos, Thailand, Cambodia, and even China. Based on a big-data port and shipping system, this study focuses on the interaction between Vietnam's inland and coastal networks and the impact of throughflow as a sea gateway for Laos to connect the world. This analysis includes network connectivity, port positions and evolution, maritime port clusters, and regional deltas using clustering methods. The relationship between the maritime networks and the economic zones of Vietnam and its neighbors was also included in the current study. In summary, Vietnam can coordinate and optimize its seaside and landside networks to contribute to its trade and globally extend its maritime network to serve itself and its region.

Multi-Armed Bandits Learning for Task Offloading in Maritime Edge Intelligence Networks

In the context of complex and dynamic marine environment, the offloading of computing tasks for ships of Internet of Things (IoT) users is a very challenging problem considering the different quality of service (QoS) requirements of maritime applications. Mobile edge computing driven by powerful computing capability and edge intelligence is taken as a promising solution, especially for the resource-constrained and delay-sensitive maritime IoT users. In this paper, we study the optimal edge server selection problem for ship IoT users to jointly minimize the latency and energy consumption for task offloading. Specifically, we first propose a novel space-air-ground-edge (SAGE) integrated maritime network architecture to offload computation-intensive IoT services at sea. Then, the latency and energy consumption of data transmission and processing during offloading are modelled. Based on the models, the edge server selection problem is formulated into a Multi-Armed Bandits learning problem, with considering the task latency requirement and energy budget. To achieve the optimal solution, a novel algorithm, referred to as UCB1-ESSS, is developed, which links the latency, energy consumption, and network constraints by introducing both reward and cost. The simulation results show that the proposed algorithm can achieve considerably lower offloading latency and weighted latency-energy cost compared with the traditional algorithms under different QoS requirements, which proves the efficacy of theproposed algorithm.

The Lower Qishon Late Bronze Age Terrestrial and Maritime Network

During the Late Bronze Age, a complex network of economic interactions constituted of various semi-independent political entities, yet economically interdependent, existed in the Lower Qishon. We conducted a comparative analysis of plainwares from different sites along the Lower Qishon to identify how they interacted during the LBA. We also performed a comparative study of the maritime-imported ceramics to uncover the maritime connections of the network. We conclude that the Lower Qishon network linked the southern Akko/Haifa Bay with the northwestern Jezreel Valley. On land, the network was in contact with Tel Hazor and the Transjordan. At sea, it was directly connected with Syro-Lebanese and Cypriote coastal sites and indirectly with Egypt, coastal Anatolia, and the Aegean.

Finding Common Ground: Halle Pastors in North America and Their Shifting Stance Towards a Transnational Mission to Native Americans, 1742–1807

Abstract While Heinrich Melchior Mühlenberg and his pastor colleagues from Halle have gone down in history for their pioneering work – organizing the Lutheran Church on North American soil – they are not known for missionary projects to Native Americans. This article examines how things changed after a second generation of Halle pastors arrived in Pennsylvania in the 1760s. It was, above all, down to Mühlenberg’s later son-in-law Johann Christoph Kunze, who had a rather different view on America’s indigenous people. During his whole lifespan in America, Kunze pursued his goal of establishing a mission to Native Americans. This engagement contributed to a paradigm shift in the Lutheran Church. In contrast to Mühlenberg and the first generation of Halle pastors, Kunze sought transnational support that was no longer exclusively centered in Halle’s Glaucha Institutions but based on pan-Protestant, maritime networks.

Roman engraved gems from Southeast Asia

In recent years our understanding of ancient maritime networks has evolved significantly. Extensive international joint excavations and a heightened interest in collecting ancient objects among local people have altogether yielded a significant number of Roman artefacts both from Mainland and Island Southeast Asia. Regarding the types of these Roman objects, a quantity of engraved gems bearing western characteristics emerges from the collected materials thereby suggesting recognition and possibly even some degree of appreciation by the local cultures. This paper examines the categories and distribution of Roman engraved gems discovered in Southeast Asia, and aims to show possible imprints on forming evaluation/acceptance of these non-local goods by the receiving cultures.

Emissions assessment of bulk carriers in China's east Coast-Yangtze River maritime network based on different shipping modes

In the past decades, resources such as iron ore were transported to the upper-middle reaches of the Yangtze River by river-sea combined mode in order to support the rapid economic development of Yangtze River Economic Zone. However, emissions from vessels have caused serious negative effect on the environment along the Yangtze River. Therefore, the Chinese government took a series of measures so as to control the emissions in this area. This paper draws comparisons among river-sea combined mode, river-sea mode and mixed mode (combination of the river-sea combined mode and river-sea mode) based on the ship emissions inventory of SOx, PM10, PM2.5, NOx, CO, HC, CO2, N2O and CH4 for 13 common cases in the existing network by bottom-up method. In addition, the paper carries out in-depth analyses, providing evidence for future ship operation directions. The results indicate river-sea mode and mixed mode which implement river-sea vessels record less unit emissions compared to the traditional river-sea combined mode. Moreover, shorter transshipment (lightning) times, proper ports of transshipping and cleaner fuels are able to reduce ship emissions significantly. Hence, we conclude that first, river-sea vessels should be encouraged; second, the initiative of a deep-water channel of the Yangtze River should be continued; and last, stricter regulations of fuels have played a significant role in reducing ship emissions.

Vessel Deployment and De-Hubbing in Maritime Networks: A Case Study on Colombo Port and Its Feeder Market

Generally, vessels are deployed as hub-and-spoke networks to achieve high slot utilization and cost efficiency for shipping lines in global maritime container shipping networks. At the Port of Colombo, most transhipment containers originate from and are destined for Indian ports, the export/import container volume of which has been rapidly increasing, and Indian ports have been developed to accommodate vessel enlargement. In such circumstances, the partial or complete abandonment of a hub (Colombo port) in this region is expected, which is known as “de-hubbing.” This study aims to clarify the impact of port developments and an increase in container cargo demand from the source country on maritime network selection from the perspective of shipping lines. We develop a mixed integer linear programming model to describe vessel deployment, including transhipment via the Colombo port and direct shipment in Indian ports. As a result of the analysis, the number of direct services to Indian ports is expected to increase when the cargo demand of Indian ports increases and the port development of Indian ports is conducted. The progress of the de-hubbing phenomenon decreases vessel size at Colombo port because the container demand at Indian ports is mostly satisfied by newly deployed trunk lines to Indian ports. This study suggests that if Colombo port expects to maintain its hub status, it is critical to consider various other incentives to attract and retain mainline carriers in addition to expanding its port infrastructure. Similarly, if India expects to receive direct calls from mainlines, it is important not only to develop their port infrastructure but also to increase their cargo demand.

A port attractiveness assessment framework: Chittagong Port’s attractiveness from the users’ perspective

This study evaluates the attractiveness of the Chittagong Port of Bangladesh from the port users’ perspective. Existing maritime literature is focused on major ports of Europe, East Asia and North America, but many secondary ports of the mainline maritime network, which play a crucial role in their countries, are overlooked. Chittagong Port is such a port having an enormous impact on the economy of Bangladesh. The perceived attractiveness of this port to its users is assessed in this study based on six factors: port connectivity, facilities, costs, service quality, policy and management, and green port management practices. Data are collected on a 7-point Likert scale for 25 measurement items, and the port attractiveness measurement model is validated using Confirmatory Composite Analysis (CCA). The results indicate that the port users’ find the port’s connectivity most attractive and green port management practices least attractive. We also observe that port users with a high frequency of port usage find Chittagong Port less attractive compared to less frequent users. These findings have significant policy implications for the port authority and policymakers to enhance the port’s attractiveness, which is in a monopolistic position handling more than 90% of international trade for Bangladesh. Further, a validation of the port attractiveness assessment framework enables researchers and practitioners to use it as a standard instrument for assessing the attractiveness of ports having similar characteristics globally.

Long Short-Term Memory and Graph Convolution Network for Forecasting the Crude Oil Traffic Flow

Understanding maritime network structure and traffic flow changes is a challenging task that must incorporate economic, energy, geopolitics, maritime transportation, and network sciences. Crude oil is the most imported energy in the world. Investigating the crude oil maritime network status and predicting the crude oil traffic flow changes has great significance for the global trade, especially for key crude oil importing/exporting regions and countries. To address this, a system-based approach using long short-term memory and graph convolution network for the crude oil traffic flow forecasting named LGCOTFF is introduced. The LGCOTFF approach constructs a maritime transportation network firstly, and then calculates and predicts the node traffic flow based on trajectory data and crude oil berth geographical position. Firstly, we construct a maritime crude oil transportation network based on supply-demand relationship, ship trajectory and route information. Then, we design an approach to calculate how many crude oil ships finished up-load/offtake tasks in a single week for each port, and gather this data to countries and regions. Finally, we design a deep learning neural network named long short-term memory and graph convolution network (L-GCN) to extract the temporal and spatial characteristics of crude oil transportation, and predict the node traffic flow. We evaluate the proposed model on China, Russia, Middle East and America respectively and observe consistent improvement of more than 10% over state-of-the-art baselines.

TRADE ROUTES OF EARLY TAMILAKAM - A STUDY OF THE ARCHAEOLOGICAL SOURCES

Trade activities through the ages have promoted interactions between distant lands connected by the networks of routes. Ancient Tamil region too participated actively in the process of exchange which was facilitated by overland routes and waterways. The diverse physiographic features of Tamilakam necessitated the commodities trade with different regions. Besides the land routes linking various parts of the subcontinent, maritime networks served as important means of communication with other countries. Although literary texts including the foreign accounts throw significant lights in this regard, archeological discoveries supplement with the information that helps in better understanding in order to draw inferences in the context of trade and commerce. This paper focuses upon the excavated remains found at important sites such as Arikamedu, Uraiyur, Korkai, Alagankulam, Poompuhar (Kaveripattinam), Porunthal, Kodumanal Karur and Pattanam (Muciri/Muziris), which enable us to draw an outline of the trade routes in ancient period. The antiquities attest to the presence of various routes for establishing contacts with the coastal and inland centres.

Mobility-Aware Resource Management for Integrated Satellite-Maritime Mobile Networks

The rapid development of the blue economy has generated fast growth in the demand for maritime communications, which requires strong network capacities. Due to the poor climate and construction conditions, maritime communications significantly lag behind their terrestrial counterparts, which hinders the application and optimization of maritime mobile services. Recently, the cloud-edge-terminal (CET) architecture has enabled terrestrial mobile users to use all devices and facilities collaboratively, which effectively alleviates network pressure and improves users' quality of experience (QoE). To bring these advantages to the maritime scenario, this article proposes an integrated satellite-maritime CET architecture, and considers the mobility of maritime vehicles in network resource management, including integrated transmission optimization, CET offloading, and proactive caching with resource-sharing maritime edge clusters. These proposals can provide a new perspective for future maritime network management to be more suitable for the mobility of maritime communication entities.

Coastal Shrines and Transnational Maritime Networks Across India and Southeast Asia by Himanshu Prabha Ray

Coastal Shrines and Transnational Maritime Networks Across India and Southeast Asia by Himanshu Prabha Ray

Cities, Diversity, and Global Maritime Networks

Maritime transport is often overlooked in urban network studies, just like cities rarely appear in shipping network analyses. However, this particular vector carries the vast majority of international trade volumes, and two-thirds of the world’s population resides in coastal areas. From a complex network perspective, this article tests the interdependencies between maritime flows and the urban hierarchy. Nearly 4 million vessel movements connecting about 6000 ports are computed to shed new light on the affinity between traffic volume, diversity, connectivity, interaction range, and city size. Main results point to the high and maintained dominance of the largest cities over three decades (1977–2008), thereby demonstrating that maritime networks are subject to urban regularities in ways similar to other transport and communication networks, despite deep contemporary changes in the distribution of port systems and supply chains. This research also underlines the need to extend the spatial unit under investigation to better catch urban effects.

Location privacy protection of maritime mobile terminals

Mobile Edge Computing (MEC) can support various high-reliability and low-delay applications in Maritime Networks (MNs). However, security risks in computing task offloading exist. In this study, the location privacy leakage risk of Maritime Mobile Terminals (MMTs) is quantified during task offloading and relevant Location Privacy Protection (LPP) schemes of MMT are considered under two kinds of task offloading scenarios. In single-MMT and single-time offloading scenario, a dynamic cache and spatial cloaking-based LPP (DS-CLP) algorithm is proposed; and under the multi-MMTs and multi-time offloading scenario, a pseudonym and alterable silent period-based LPP (PA-SLP) strategy is proposed. Simulation results show that the DS-CLP can save the response time and communication cost compared with traditional algorithms while protecting the MMT location privacy. Meanwhile, extending the alterable silent period, increasing the number of MMTs in the maritime area or improving the pseudonym update probability can enhance the LPP effect of MMTs in PA-SLP. Furthermore, the study results can be effectively applied to MNs with poor communication environments and relatively insufficient computing resources.

The container transport system during Covid-19: An analysis through the prism of complex networks

This paper analyses the changes on the maritime network before and after the Covid-19 outbreak. Using a large sample of vessel movements between ports, we show a decrease in the global maritime connectivity and significant differences between ports and inter-port links. Furthermore, we find that Covid-19 mitigation measures implemented by governments affected regional port hierarchies differently, with a reduction in port concentration in Europe and Africa and an increase in Asia and North America. Globally, very large ports and small but densely inter-connected ones resisted better to the crisis than the others, while small transshipment hubs and bridges appear to have been more negatively impacted. These findings have implications for the design of more resilient port strategies and transport policies by states and firms.