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EN
The paper presents the method of determining ships traffic stream parameters by means of regression method. The aim of the studies was to determine the correlation between the ship's parameters and the parameters of the fairway. Developing the presented model with information on the position of the vessel's antenna and information on the accuracy of position determination will allow creating a model for predicting the parameters of waterways.
2
Content available Sharing ships’ weather data via AIS
EN
In the aftermath of the sinking of the US-flagged containership El Faro in October 2015, one of the U.S. National Transportation Safety Board’s (NTSB) recommendations was for the National Oceanic and Atmospheric Administration (NOAA) to explore increasing the collection of weather data from ships in order to improve the weather forecast products that they distribute. Currently NOAA runs the Voluntary Observing Ship (VOS) program, where ships voluntarily submit weather observations to NOAA. However, only a small fraction of the thousands of vessels sailing worldwide participate in this program, and VOS weather observations are submitted infrequently, typically four times per day via a mainly manual process. One method being explored to automate and increase the frequency of data submittal is by using the existing Automatic identification System (AIS) equipment installed aboard vessels. Most commercial ships (in particular those subject to the International Maritime Organization's (IMO) Safety of Life and Sea (SOLAS) convention) have a Class A AIS transceiver installed to comply with mandatory carriage requirements. Many vessels not required to carry AIS equipment voluntarily install AIS transceivers (either Class A or B). All of these AIS transceivers (except for the Class B “CS”) can be used to transmit an AIS message 8 (broadcast binary message) by sending the transceiver an appropriately formatted NMEA sentence (BBM). Weather data can be embedded in an AIS application-specific message (ASM) carried by the AIS message 8 and automatically transmitted by the ship. This transmission can be received by terrestrial AIS stations (when in range) or by satellite AIS receivers. The AIS weather data can then be converted into the appropriate format and forwarded to the weather forecasting offices for use in models and weather predictions. This data may also be of use to other researchers monitoring climate change or other environmental factors. By leveraging this existing base of AIS transmitters, the volume of weather data being sent to weather forecast offices and others could be greatly increased. The U.S. Army Corps of Engineers (USACE) and U.S. Maritime Administration (MARAD) have been exploring the feasibility of this concept. Following a simple bench test performed by Alion Science in September 2018, an initial proof-of-concept was tested aboard the MARAD vessel Cape Wrath while moored in Baltimore in October 2018. After this successful demonstration, a prototype was installed on the Massachusetts Maritime Academy training ship TS Kennedy during her training cruise Jan-Feb 2019. During this cruise, the AIS equipment aboard the ship transmitted weather data at 3-minute intervals. Several different ASM formats were tested, including two developed specifically for this test to improve satellite reception. This report will discuss the concept, the demonstrations, and the results to date including the efficacy of the various ASM formats.
EN
The Automatic Identification System (AIS) offers automatic traffic control and collision avoidance services to the maritime transportation sector worldwide. Because AIS lacks security mechanisms, it is vulnerable to misuse and exploitation by unlawful adversaries (e.g. sea-pirates, terrorists, smugglers). To address the security issues of the AIS, in an earlier paper [1], we proposed the deployment of a Maritime Certificate-less Identity-Based (mIBC) public-key cryptography infrastructure that enhances AIS with on-demand anonymity, authentication, and encryption capabilities. In this paper we address implementation aspects of that infrastructure. In particular, we propose to use the Sakai-Kasahara Identity-Based Encryption (IBE) approach to implement the mIBC infrastructure, following the IEEE 1363.3-2013 standard for Identity-Based Cryptography.
EN
A Yagi plasma antenna model was established by HFSS according to the relationship between plasma dielectric constant and electron density. The patterns were simulated by changing plasma parameters and the number of director dipoles. Results show that when the passive vibrators were switched off, the antenna is omnidirectional antenna. The directionality increases with the increase of the number of passive dipole and the main lobe of which narrows down. Then the plasma Yagi antenna model is established by plasma tube, the gain changed by changing the number of passive dipoles, so the plasma Yagi antenna has a very good reconfigurability. Results prove that the feasibility of the plasma Yagi antenna can be used on AIS base station of Ships’ Routeing waters. It can promote the communication and capability of maritime supervision in Ships’ Routeing waters.
EN
The Automatic Identification System (AIS) provides situational awareness for vessels at sea. AIS has a number of known security vulnerabilities that can lead to a several types of attacks on AIS, including the ability to create ghost vessels, false warning or meteorological messages, or bogus virtual aids-to-navigation (AtoN). A number of methods, with varying levels of complexity, have been proposed to better secure AIS and, indeed, emerging AIS protocols will implement some of these mechanisms. Nevertheless, little has been done to secure the current standards, which will remain in use for some time. This paper presents Protected AIS (pAIS), a demonstration of capability implementation using public-key cryptography methods to address several AIS security vulnerabilities, maintain backward compatibility, and be able to interoperate with non-pAIS devices.
EN
The operational measures in which a ship needs to avoid specified areas to escape ship stability failures were discussed at the International Maritime Organization as a part of the second generation intact stability criteria. It is necessary that the rationality and practicality of the operational measures are carefully investigated. In this study, master’s route decision-making criteria of trans-ocean vehicle carriers have been clarified by comparing the Pacific and the Atlantic data, derived from Satellite AIS and ocean wave data. Features of voyage routes of each ocean were discussed, followed by analysis of the encountered wave direction and height during a voyage. The master’s route selection criteria were defined by comparing the probability densities of the wave heights that occurred in the navigable area and that of the actual encountered waves. The navigation hours in a stormy area were also studied.
EN
Digital selective calling (DSC) has a certain drawbacks, which have led to the fact that it is practically not used in address radio communications. Attempts to improve it only within the DSC system itself did not lead to any noticeable results due to neglecting of real user needs. The article proposes an approach to improve the user interface of DSC based on the integration of VHF MF/HF DSC equipment with the INS within the three main outputs of strategic direction of e-navigation development related to the integration of communication and navigation systems and, in particular, the S-mode. This approach allows us to significantly simplify the DSC user interface, based on the standardization of DSC integration for all three VHF MF/HF communication sub bands. For implementation such standardization an additional inclusion into the integration a satellite AIS system should be done. The feasibility of the proposal is supported by the existence of relevant IEC standards and IMO documents. The possibility of increasing the cyber security level of AIS messages in this interface is also considered.
EN
Ship route planning is one of the key issues in enhancing traffic safety and efficiency. Many route planning methods have been developed, but most of them are based on the information from charts. This paper proposes a method to generate shipping routes based on historical ship tracks. The ship's historical route information was obtained by processing the AIS data. From which the ship turning point was extracted and clustered as nodes. The ant colony algorithm was used to generate the optimize route. The ship AIS data of the Three Gorges dam area was selected as a case study. The ships’ optimized route was generated, and further compared with the actual ship's navigation trajectory. The results indicate that there is space of improvement for some of the trajectories, especially near the turning areas.
EN
Optimal ship tracks computed via the VISIR model are compared to tracks recorded by the Automatic Identification System (AIS). The evaluation regards 43 tracks in the Southern Atlantic Ocean, sailed during 2016-2017 by different bulk carriers. In this exercise, VISIR is fed by wave analysis fields from the Copernicus Marine Environment Monitoring Service (CMEMS). In order to reproduce vessel speed loss in waves, a new methodology is developed, where kinematic information from AIS is fusioned with wave information from CMEMS. Resulting VISIR tracks are analyzed along with AIS tracks in terms of their topological features and duration. The tracks exhibit quite diverse topological shapes, including orthodromic, loxodromic, and other paths with complex and dynamic diversions. The distribution of AIS to VISIR track durations is analyzed in terms of several parameters, such as the AIS to VISIR track length and their Fréchet distance. Model features of VISIR affecting the results are discussed and future developments suggested by the results are outlined.
EN
Ship navigation and operational activities at sea need meteorological and hydrographic information to enhance safety and efficiency. Besides observations collected from deployed data buoys, marine meteorological information services rely on weather observation reports from ships to increase the data density and thus service quality. Automatic Identification System (AIS), adopted internationally to facilitate ship-ship and ship-shore data exchange, has developed into communication links between ship/shore and buoys with many potential applications. This paper presents AIS applications designed and implemented for marine meteorological information services in a long-term project initiated by the Central Weather Bureau of Taiwan. Achievements of this initiative include: versatile service delivery via shore-based AIS network to shipborne application platforms such as smart phones, remote controllable moving weather data collection, and assisted sharing of weather observation reports from ships. Typhoon forecast and warning is one of the key applications implemented for this region.
11
EN
This paper proposes an approach for identifying and characterizing shipping routes using information contained in Automatic Identification System messages broadcasted by ships and recorded by the coastal Vessel Traffic Service centre. The approach consists of using historical Automatic Identification System data to build a graph, where nodes are cells of a grid covering the geographical area being studied and the weights of directional edges are inversely related to ship movements between cells. Based on this graph, the Dijkstra algorithm is used to identify a potential safe route, assumed to be the most used route by ships between two locations. A second graph is created simultaneously, with the same nodes and edges, but with edge weights equal to the average speed of transitions between cells, thus allowing the determination of the average speed profile for any possible path within the graph. The proposed approach is applied to two scenarios: an approach to the port of Lisbon and the entry through the fairway to a RO-RO terminal in the port of Setubal in Portugal.
EN
This article presents the movement vector research conducted in the radar laboratory of Gdynia Maritime University and during vessel cruises. The precision of designating the vessels' location, course, speed and CPA were researched using on-baord radars and AIS data. It is concluded that the precision of designating the researched parameters is greater than the International Maritime Organization requires.
EN
The traffic density is a basic characteristic of marine traffic for some navigational area. In the case of narrow channels such as Strait of Split (Splitska vrata), apart from the traffic density, the number of simultaneous ship passages is also important as well as ships characteristics. Based on such data, additional navigational safety guidelines and regulations may be planned for the observed area. The purpose of this research is to determine the number of simultaneous ship passages via Strait of Split for a certain period of time. Collected AIS data in SPNMEA format was decoded by AIS Decoder online program to csv file. For five randomly selected days in the summer period, based on AIS data, the number of simultaneous ship passages was determined and ships information presented.
EN
According to the IMO recommendation when the target data from radar tracking and AIS are both available and the association criteria are fulfilled such that the radar and AIS information are considered as for one physical target, then as a default condition in radar equipment should be automatically selected and displayed the AIS target symbol and the alphanumerical AIS target data only. The article presents research conducted in real sea conditions on the reliability of information presented by the ship's AIS and ARPA about the passing distance with the other vessel tracked by radar equipment and fitted with AIS.
EN
The article presents analysis of the automatic radar plotting aid (ARPA) and automatic identification system (AIS) indications reliability performed on the base of the results of measurements conducted on merchant vessels at sea. In the first part of the article titled “Comparative study of the accuracy of AIS and ARPA indications. Part 1. Accuracy of the CPA indications” are described: vessels on which the tests were carried out, AIS and radar equipment installed on them, observed meeting situations and accuracy of the CPA indication. In this article are discussed, for the same meeting situations, accuracy of the information on true course and true speed of the opposite vessel presented by ARPA and AIS and correlation between this accuracies and errors of the CPA indication.
EN
The maritime transportation system is increasingly a target of cyber attacks. This paper describes a taxonomy that supports the creation of adversarial cyber models, risk mitigation, and resiliency plans as applied to the maritime industry, using the Automatic Identification System as a specific illustration of the approach. This method has already been applied to the aviation sector; retooling it for a maritime example demonstrates its broad applicability to the transportation sector, in general.
EN
This paper considers the degree of competition among small and medium-sized container ports located in a multi-port gateway region. The level of port competition is evaluated by means of an analysis of the revealed preferences in the port-calling pattern of container feeder vessels deployed on their various links and routes. Unit of analysis is feeder vessel sailing legs and ports stays at/between adjacent container ports. At these ports’ terminals, ships are moored and loading and unloading of containers are performed. The vessel movement data is provided by the Automatic Identification System (AIS). A study of the principal container ports in the Oslo Fjord area is performed, measuring the actual container feeder traffic during the year of 2015. It is demonstrated to which extent ports in the Oslo Fjord region are acting as substitutes, and to which extent they are functioning more as a complement to each other.
18
EN
Automatic Identification System (AIS) is primarily used as a tracking system for ships, but with the launch of satellites to collect these data, new and previously untested possibilities are emerging. This paper presents the development of heuristics for establishing the specific ship type using information retrieved from AIS data alone. These heuristics expand the possibilities of AIS data, as the specific ship type is vital for several transportation research cases, such as emission analyses of ship traffic and studies on slow steaming. The presented method for developing heuristics can be used for a wider range of vessels. These heuristics may form the basis of large-scale studies on ship traffic using AIS data when it is not feasible or desirable to use commercial ship data registers.
19
EN
It is necessary to develop a useful application to use big data like as AIS for safety and efficiency of ship operation. AIS is very useful system to collect targets information, but this information is not effective use yet. The evaluation method of collision risk is one of the cause disturb. Usually the collision risk of ship is evaluated by the value of the Closest Point of Approach (CPA) which is related to a relative motion. So, it becomes difficult to find out a safety pass in a congested water. Here, Line of Predicted Collision (LOPC) and Obstacle Zone by Target (OZT) for evaluation of collision risk are introduced, these values are related to a true motion and it became visible of dangerous place, so it will make easy to find out a safety pass in a congested water.
EN
Pilotage is considered as the most critical leg of navigation and a complex operation in maritime domain. In this paper, we argue that Distributed Situation Awareness (DSA) is an important construct in pilotage as the information required to carry out operations is distributed between agents and artefacts. We identify the central themes from the theory of DSA which are useful in describing modern day complex socio-technical systems. Further, based on the central themes, we propose guidelines for evaluating bridge teams involved in pilotage operations.
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