227 research outputs found

    Hybrid dynamic modeling and receding horizon speed optimization for liner shipping operations from schedule reliability and energy efficiency perspectives

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    Uncertainties in port handling efficiency can cause port delays in the liner shipping system. Furthermore, policies on carbon emission reduction, such as EEXI standards, restrict the potential for speed optimization in liner shipping operations. Traditional tactical planning speed optimization is unsuitable for operational-level decision making, leading to unreliable schedules. From a schedule-reliability and energy-efficiency perspective, we propose a real-time speed optimization method based on discrete hybrid automaton (DHA) and decentered model predictive control (DMPC). We use a dynamic adjustment of sailing speed to offset the disturbance caused by port handling efficiency uncertainties. First, we establish a DHA model that describes each ship’s hybrid dynamics of state switching between sailing and berthing; then, we develop a prediction model for the DMPC controller, which is analogous to the DHA model. The schedule is transferred into time–position coordinates as controller reference trajectories in the receding horizon speed optimization framework. We consider determining tracking errors, carbon emissions, and fuel consumption as our objectives, and we carry out engine power limitation (EPL) analysis for the sample ship, which turns the EEXI standards into constraints. We attain the recommended speed by solving a mixed-integer optimization. We carry out a case study, and our results indicate the effectiveness of our proposed DHA-DMPC scheme in lowering port delays and achieving the best trade-off between schedule reliability and energy efficiency. Additionally, we conduct further experiments to analyze the impacts of various carbon reduction policies on the performance levels of liner shipping operations

    Integration Strategies for Sustainable Positioning of Shipping Companies in the Maritime Trade Market System

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    Introduction. The maritime transport of individual countries, operating in a single space of the World Ocean, determines the tasks and problems of creating standard requirements for the reliability of cargo flows and system security of operation. This significantly differentiates the conditions for the development of maritime transport as a subsystem of the global maritime transport market between its individual structures, on the one hand, and national maritime transport complexes, on the other. This is what determines the expediency of various integration processes in the system of the maritime trade market. Aim and tasks. The study examined the role of integration technologies in the global maritime trade market and the analysis of the development of the country's maritime transport complex in relation to its real needs for participation in integration processes, as well as possible strategies for integration principles and finding ways to implement such strategies in the activities of the country. Results. The study resulted in the identification of three approaches to the forms of integration in the maritime trade market. The first form includes the processes of creating the gross national product based on the international division of labor, when the global sectoral equilibrium is achieved by combining the technology of producers of one country with the resources and territory of another state. The second form of integration is the M&A strategy for the further development of shipping companies and other enterprises of the maritime complex. The third form is the interaction of individual maritime transport enterprises in intermodal connections. The implementation of all the above forms of integration is in line with globalization trends in the socio-economic development, achievements of technological progress and strategic interests of shipping companies. Conclusions. The development of maritime transport in terms of integration characteristics and technical priorities reflects the principle of sustainability. At the same time, activities are separated in the system of achieving a balance in the state of the main components of the transport services market according to the criteria for optimizing the investment flow. The latter necessitates a constant search for optimization of the fleet's carrying capacity and cargo terminal throughput. The main thing is to study the optimization of development from the perspective of both macroeconomic and business structures

    Port choice: A frequency-based container assignment model

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    The process of containerization has connected the world with a cost-effective freight service, successfully forming a competitive global market. Mixed freight shipping has changed dramatically due to containerization and globalization. The port system has experienced a tough time keeping pace with globalisation in terms of its roles and functions in liner shipping. Consequently, port choice has become a challenging problem to analyse with many stakeholders and complex circumstances. The literature formulating the basis of this maritime container assignment model can be identified as a combination of port choice modelling, a freight flow model and empty container repositioning. It is observed that the maritime container assignment problem shares a greater affinity with transit assignment than with traffic assignment conventionally applied freight in the four step approach, because containers are generally carried by shipping lines which operate services on fixed routes or port rotations. A model capable of representing full and empty container flows at a global level would be useful to almost every stakeholder in the container liner shipping industry, such as shippers, shipping lines, port authorities, terminal operating companies, regional and national planning authorities, marine insurance companies, and others. The classic frequency-based transit assignment approach of Spiess and Florian is transferred and applied to maritime containers as the foundation for a global maritime container assignment model. The first version of this model assigned full and empty containers to routes to minimise expected travel time, which consists of sailing time between ports and dwell time at intermediate transhipment ports. Service frequency and port capacity influence the pattern of full and empty container flows and therefore port choice. In this thesis, the model is further developed to fit the reality of container liner shipping by minimising expected cost rather than expected travel time. The objective is now to assign container flows to routes to minimize the sailing costs and expected dwell costs at the origin port and intermediate transhipment ports. The constraints included are extended to include the maximum number of containers each route can carry. Finally, the capabilities of the cost-based container assignment model are explored through a case study of the Europe-Far East trade lane. A range of strategy and policy options, such as a shipping line planning a new route or modifying an existing route and a port authority considering expansion, are simulated. A possible approach to model validation through independent data is proposed. Recommendations for future research are provided at the end of the thesis. Many aspects are covered in the thesis; an origin-destination matrix estimation, automated virtual (task) network construction from routes and schedules, improvements to the probability distribution used for ship arrivals, a validation procedure, and model extension from port-to-port movements to door-to-door container movements

    Supply Chain Disruption Costs Study in International Containerised Maritime Transportation

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    The global economy relies highly on international trade, and the international maritime transport system acts as the lifeblood carrying and transporting materials and goods globally, realizing the economy globalization in an effective and efficient way. However, globalization increases the interdependence and complexity of global supply chains and drives it to be more vulnerable to disruptions. Meanwhile, the international marine transport system is a complex and intertwined system exposed to high risks and decreased safety due to its very accessibility and operational flexibility. Thereby, global supply chains integrated with international maritime transportation systems are inherently vulnerable to various disruptions. Studies of supply chain disruptions particularly quantifying transport related disruption costs are becoming increasingly important. However, research on maritime transport related supply chain disruptions, in particular, quantifying its disruption costs is under-represented in the transport literature, due largely to the features of supply chain disruptions, but also because of the complexity of maritime related supply chains. Current research in transportation has tended to concentrate on shippers’ transport mode choice and port selection. In the context of a global market, however, the behaviour of maritime containerised shippers has to be viewed as a complex decision and an integral element of the supply chain management strategy. Those shippers’ transportation choice decisions should be emphasized and studied to reveal their behaviour changes between normal operations and disruption circumstance. This research adds to the paucity work on investigating the maritime transport related supply chain disruptions and quantifying its disruption costs based on shippers’ maritime transportation choice behaviour. It presents the results of a microanalysis of freight transport choice decisions in an international containerised maritime transport chain context. The Latent Class Model (LCM) is applied to identify the key service attributes and its preference heterogeneity in maritime transportation and to estimate the marginal values for the quality of maritime transport service with and without a disruption, simultaneously, quantifying the disruption costs through comparing each attribute’s marginal value difference between normal and disruption operations. The Seemingly Unrelated Regression model (SURE) is utilized to explore the sources influencing shippers’ preference heterogeneities. In doing so, we are able to gain an understanding as to where and how much should be invested in order to facilitate recovery in the case of a disruption based on the view of the maritime participants’ perspectives. The research results confirm freight rate, transit time, reliability, damage rate, and frequency as the key service attributes influencing shippers’ transport choice. They also reveal shippers’ VOT increase by more than four-times, VOR nearly double, and VOD increase about twenty percent if a disruption takes place, and identify shippers’ transport decisions vary with its product, shipment, company and supply chain characteristics no matter with or without a disruption. This research quantifies the costs of supply chain disruption in containerised maritime transport context for the first time, and its results provide useful industrial implications for maritime transport chain related parties

    Supply Chain Disruption Costs Study in International Containerised Maritime Transportation

    Get PDF
    The global economy relies highly on international trade, and the international maritime transport system acts as the lifeblood carrying and transporting materials and goods globally, realizing the economy globalization in an effective and efficient way. However, globalization increases the interdependence and complexity of global supply chains and drives it to be more vulnerable to disruptions. Meanwhile, the international marine transport system is a complex and intertwined system exposed to high risks and decreased safety due to its very accessibility and operational flexibility. Thereby, global supply chains integrated with international maritime transportation systems are inherently vulnerable to various disruptions. Studies of supply chain disruptions particularly quantifying transport related disruption costs are becoming increasingly important. However, research on maritime transport related supply chain disruptions, in particular, quantifying its disruption costs is under-represented in the transport literature, due largely to the features of supply chain disruptions, but also because of the complexity of maritime related supply chains. Current research in transportation has tended to concentrate on shippers’ transport mode choice and port selection. In the context of a global market, however, the behaviour of maritime containerised shippers has to be viewed as a complex decision and an integral element of the supply chain management strategy. Those shippers’ transportation choice decisions should be emphasized and studied to reveal their behaviour changes between normal operations and disruption circumstance. This research adds to the paucity work on investigating the maritime transport related supply chain disruptions and quantifying its disruption costs based on shippers’ maritime transportation choice behaviour. It presents the results of a microanalysis of freight transport choice decisions in an international containerised maritime transport chain context. The Latent Class Model (LCM) is applied to identify the key service attributes and its preference heterogeneity in maritime transportation and to estimate the marginal values for the quality of maritime transport service with and without a disruption, simultaneously, quantifying the disruption costs through comparing each attribute’s marginal value difference between normal and disruption operations. The Seemingly Unrelated Regression model (SURE) is utilized to explore the sources influencing shippers’ preference heterogeneities. In doing so, we are able to gain an understanding as to where and how much should be invested in order to facilitate recovery in the case of a disruption based on the view of the maritime participants’ perspectives. The research results confirm freight rate, transit time, reliability, damage rate, and frequency as the key service attributes influencing shippers’ transport choice. They also reveal shippers’ VOT increase by more than four-times, VOR nearly double, and VOD increase about twenty percent if a disruption takes place, and identify shippers’ transport decisions vary with its product, shipment, company and supply chain characteristics no matter with or without a disruption. This research quantifies the costs of supply chain disruption in containerised maritime transport context for the first time, and its results provide useful industrial implications for maritime transport chain related parties

    The provision of efficient transport services in the Iranian maritime and land transport interface.

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    Doctor of Philosophy in Economics. University of KwaZulu-Natal, Westville 2014.This research investigates the efficiency of Iran’s transport system with reference to the seaborne trade and sustainable development of ports, shipping services, logistics centres and transit corridors as the overall objectives. The reason this study is relevant, is it introduces Iran through its potentially cost-effective transport advantages to create an alternative source of revenue for a country that is heavily dependent on oil income. To successfully analyse the provision of effective transport services in the Iranian maritime and land transport interface, the emerging Iranian transport corridors have been under close observation, and a scenario planning approach mixed with a descriptive exploratory comparative cost analysis has been applied. This methodology comprises two stages. The first stage involves the identification of the main features, limitations and challenges of the chosen transport corridors through which the different infrastructure and the development of main ports, routes and corridors are described according to the available data and information. The second and more analytical stage utilises this base to estimate and compare the comparative costs of these through-transport routes, with a view to establishing their cost effectiveness. As research recommendations, the optimisation of efficiency of some alternative land haulage routes, and the International North-South Transport Corridor (INSTC) as a sea cum-land route-rail are elaborated

    Enhancing Civil Military Integration for Strategic Sealift

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    Our political and military leaders consider the efficient deployment and maintenance of personnel and hardware to be of equal importance to the task of planning the military operation. However, inasmuch as today’s military budgets are under great financial strain the military needs to rely on the civilian merchant navy for the provision of additional sealift capability. NATO acknowledges that member countries' ability to meet the politically desired levels of strategic sealift could be inadequate. Without a basic knowledge of the workings of the merchant navy, the military transportation desk officer cannot make an informed decision concerning the sealift capabilities required for strategic defence, humanitarian aid or refugee evacuation. This thesis reviews the range of militarily suitable commercial shipping and the different processes for chartering appropriate vessels while also considering the present state of civil/military synergies within NATO. It also examines the different types of insurance, including hull & machinery, third- party liability and commercial war-risks insurance and presents an overview of the problem of piracy. Its objective is to provide an introduction to the complex operational workings of the merchant navy for the military transportation officer. It is hoped that such knowledge could improve the sealift project not only in terms of operational effectiveness but also through increasing financial efficiency over a broad range of military and civil emergency maritime transportation services. Finally, two case studies are examined to demonstrate that there exists a plethora of solutions to the indicated challenges. A suggested handbook and flowchart are presented to assist in the implementation of this study's conclusions concerning the enhancement of acquired strategic sealift assets for defence, humanitarian aid or refugee evacuation

    Bundling Strategies in Global Supply Chains

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    The development of logistics has offered a wide range of new business opportunities for transport operators. Shipping lines have been taking advantage of these opportunities and have expanded their business scope beyond the movement of cargo, to include, for example, coordination among transport modes, route rationalisation and even value added logistics services. Carriers offer today transportation as part of integrated global supply chain solutions in an attempt to provide a better service to their customers as well as improve their bottom lines. This appears to be a winning strategy since an increasing number of industry players are investing in logistics operations and infrastructure. The offering of products and services jointly as a package or bundle is a common marketing strategy in a variety of industries and also appears to be a successful strategy for enhancing shipping lines’ competitiveness and profitability. Only limited research is available though to better understand under what conditions such bundled sales are possible; what attitude shippers show towards this industry trend; how bundling strategies could be developed optimally; and how they could be priced. This thesis is a contribution to research in this area and provides an analysis of the viability and the benefits of bundling strategies in the container industry, and specifically with reference to the joint provision of ocean transportation and other logistics services

    LOGISTICS IN CONTESTED ENVIRONMENTS

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    This report examines the transport and delivery of logistics in contested environments within the context of great-power competition (GPC). Across the Department of Defense (DOD), it is believed that GPC will strain our current supply lines beyond their capacity to maintain required warfighting capability. Current DOD efforts are underway to determine an appropriate range of platforms, platform quantities, and delivery tactics to meet the projected logistics demand in future conflicts. This report explores the effectiveness of various platforms and delivery methods through analysis in developed survivability, circulation, and network optimization models. Among other factors, platforms are discriminated by their radar cross-section (RCS), noise level, speed, cargo capacity, and self-defense capability. To maximize supply delivered and minimize the cost of losses, the results of this analysis indicate preference for utilization of well-defended convoys on supply routes where bulk supply is appropriate and smaller, and widely dispersed assets on shorter, more contested routes with less demand. Sensitivity analysis on these results indicates system survivability can be improved by applying RCS and noise-reduction measures to logistics assets.Director, Warfare Integration (OPNAV N9I)Major, Israel Defence ForcesCivilian, Singapore Technologies Engineering Ltd, SingaporeCommander, Republic of Singapore NavyCommander, United States NavyCaptain, Singapore ArmyLieutenant, United States NavyLieutenant, United States NavyMajor, Republic of Singapore Air ForceCaptain, United States Marine CorpsLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyCaptain, Singapore ArmyLieutenant Junior Grade, United States NavyCaptain, Singapore ArmyLieutenant Colonel, Republic of Singapore Air ForceApproved for public release. distribution is unlimite
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