International Journal of e-Navigation and Maritime Economy最新文献

A robust adaptive control approach is proposed for underactuated surface ship linear path-tracking control system based on the backstepping control method and Lyapunov stability theory. By employing T-S fuzzy system to approximate nonlinear uncertainties of the control system, the proposed scheme is developed by combining “dynamic surface control” (DSC) and “minimal learning parameter” (MLP) techniques. The substantial problems of “explosion of complexity” and “dimension curse” existed in the traditional backstepping technique are circumvented, and it is convenient to implement in applications. In addition, an auxiliary system is developed to deal with the effect of input saturation constraints. The control algorithm avoids the singularity problem of controller and guarantees the stability of the closed-loop system. The tracking error converges to an arbitrarily small neighborhood. Finally, MATLAB simulation results are given from an application case of Dalian Maritime University training ship to demonstrate the effectiveness of the proposed scheme.

Long-range visual marine aids to navigation are not required for current marine navigational practices. Therefore, the objective of this study was to develop a minimum luminous range for major lighthouses that are still in existence to sustain the operation of the lighthouses in the future. Two steps were involved in the determination of the minimum luminous range, namely the modification of the existing geographical range formula, and the finding of a strong linear correlation between the light intensity and the luminous range with the lowest gradient possible in a graph. The application of the minimum luminous range would eliminate the loom of light beyond the geographical range of the lighthouse. This approach was applied to seven major lighthouses in Peninsular Malaysia, which resulted in a minimum luminous range of between 12 nm to 14 nm, which was a reduction from the existing range of 18 nm to 25 nm. The validation of the minimum luminous range was performed in two ways; using a Full Mission Ship Simulator (FMSS), and matching the proposed minimum luminous range with the lighting system available. The results of the validation by using the FMSS between the luminous range of 25 nm and 14 nm showed that the light could be sighted and identified at 58.7 nm and 58.6 nm, respectively, which was, therefore, not significant. The validation by matching with the lighting equipment available in the market showed that the eight-tier VLB-44, which has replaced the rotating lighting system in the US since 2008, was highly matched with the proposed minimum luminous range. This further validated the minimum luminous range. The minimum luminous range is sufficient for current navigational uses and may reduce the costs for procuring and maintaining lighting systems, and will be able to sustain the operations of lighthouses in this GNSS age.

Based on the inner-effect mechanism of transport infrastructure and regional economic growth, this paper builds a specialized spatial weight matrix by utilizing the panel data from 31 provinces in New Silk Road Economic Belt (NSREB) and other areas from 2005 to 2014, and combines with the spatial panel model to analyze the spatial spillover effects of transport infrastructure. According to the analysis, the transport infrastructure plays an obvious lead role in regional economy growth alongside the NSREB, and the economic growth invigorates common development in surrounding regions. In addition, differences were observed among the different transport infrastructure with regard to their influences on regional economic development, as the highway transport affects regional economic growth to a larger degree than railway transport.

Ocean economy plays a crucial role in the strengthening maritime safety industry and in the welfare of human beings. Electric Submersible Pumps (ESP) have been widely used in floating platforms on the sea to provide oil for machines. However, the ESP fault may lead to ocean environment pollution, on the other hand, a timely fault diagnosis of ESP can improve the ocean economy. In order to meet the strict regulations of the ocean economy and environmental protection, the fault diagnosis of ESP system has become more and more popular in many countries. The vibration mechanical models of typical faults have been able to successfully diagnose the faults of ESP. And different types of sensors are used to monitor the vibration signal for the signal analysis and fault diagnosis in the ESP system. Meanwhile, physical sensors would increase the fault diagnosis challenge. Nowadays, the method of neural network for the fault diagnosis of ESP has been applied widely, which can diagnose the fault of an electric pump accurately based on the large database. To reduce the number of sensors and to avoid the large database, in this paper, algorithms are designed based on feature extraction to diagnose the fault of the ESP system. Simulation results show that the algorithms can achieve the prospective objectives superbly.

The competition of maintenance services in the offshore wind industry is continually increasing. The quality of the services acts as the distinguishing feature in the industry. Furthermore, there are public standards, which lead to the permanent necessity to offer further education and training programs for employees. To meet the requirements for further training in the specific field of application within the offshore wind industry, a gamified e-learning application has been developed and is introduced in this paper. It consists of a complete solution, which contains the automated analysis of service protocols to identify qualification needs, the involvement of service technicians in the generation of learning materials, the preparation, transmission as well as the further development of those materials in accordance with the principles of e-learning. Finally, the solution contains a gamified mobile application for qualification, which is designed to meet the individual learning needs of the service technicians. This concept paper follows a problem-centred approach. Based on the current state of technology and research, the problem and motivation are identified and the urgency is verified. Furthermore, a detailed specification of the solution and a first implementation approach is presented.

The constant increase in marine traffic and the simultaneous growth of the demand for exploiting marine areas (e.g., installing offshore wind power plants) require an adequate planning strategy for managing high traffic volumes. Maritime Spatial Planning (MSP) is the process of public development of an allocation plan for distributing, both spatially and temporally, human activities in marine areas. The adoption of e-Navigation is a possible solution for improving safety and security at sea by integrating maritime information on board and ashore. Automatic Identification System (AIS) data represents a fundamental source of information, since the analysis of AIS data can highlight the presence of congested areas as well as of illegal actions, such as smuggling, pollution, and unauthorized phishing in protected areas. Indeed, those activities are often characterized by abnormal manoeuvres that can be recognized by analyzing the routes of the vessels. However, the huge dimension of the AIS data to process requires the adoption of careful strategies for the data visualization. In this paper, we present a complete pipeline for visualizing ship routes from raw AIS data, which is a fundamental pre-requisite for carrying out a significant AIS-based route analysis, and describe a real case study, where 90 million AIS records, corresponding to one month of world-wide observations, are visualized using only open-source software.

The natural gas market has been expanding in size and has attracted particular attention across the global energy market. Although most natural gas transportation is carried out through pipelines, almost one third of it is done with the help of merchant vessels, capable of carrying liquefied natural gas. These LNG carriers have a special design and thus can be treated as a separate class of global fleet. New vessels are huge capital investments by vessel owning companies and just like other vessel classes; the new shipbuilding prices for the LNG segment continue to be a key aspect in the decision making of business players. Additionally these prices can be volatile as new ship building prices fluctuate with time. This paper attempts to analyse the volatility of new ship building prices of LNG carriers. For the study, the average ship building prices for all the LNG carriers having volume carrying capacity is between 160,000 – 173,000 cbm to be delivered between 2016 – 2019 were taken into account. For the analysis, GARCH and EGARCH methods were applied on the data set. The analysis concluded that there is a great deal of volatility in the new ship building prices of LNG vessels. It was also identified that negative shocks were more persistent the positive shocks.

Supply chain is usually represented by a network (which is called supply chain network) that contains some nodes. In a supply chain network these nodes are suppliers, plants, distribution centers and customers which are some facilities connected by some arcs to each other. The arcs connect the nodes in the direction of their production flow, meaning that each arc shows a route between the facilities for transporting the products. A multi-stage supply chain network (MSCN) is defined as a sequence of multiple supply chain network stages. This paper addresses a typical supply chain network problem which is based on a two-stage single-product system under uncertain conditions such that both cost and constraint parameters are interval numbers. The combination of these uncertain parameters are considered in this typical problem for the first time. In this case, two different order relations (the order relations ≤_UC and ≤_HW) for interval numbers are considered. Then, two solution procedures are developed in order relations for the interval two-stage supply chain network design problem. The efficiency of the proposed method is illustrated by a numerical example where it is proved that the relation ≤_HW shows better performance than the relation ≤_UC.

Many maritime accidents have been caused by human-error including such things as inadequate watch keeping and/or mistakes in ship handling. Also, new navigational equipment has been developed using Information Technology (IT) technology to provide various kinds of information for safe navigation. Despite these efforts, the reduction of maritime accidents has not occurred to the degree expected because, navigational equipment provides too much information, and this information is not well organized, such that users feel it to be complicated rather than helpful. In this point of view, the method of representation of navigational information is more important than the quantity of that information and research is required on the representation of information to make that information more easily understood and to allow decisions to be made correctly and promptly. In this paper, we adopt Augmented Reality (AR) technologies for the representation of information. AR is a 3D computer graphics technology that blends virtual reality and the real world. Recently, this technology has been widely applied in our daily lives because it can provide information more effectively to users. Therefore, we propose a new concept, a navigational system based on AR technology; we review experimental results from a ship-handling simulator and from an open sea test to verify the efficiency of the proposed system.