scholarly journals Software and technological complex of identification of sea vessels based on the use of radar space images Sentinel 1

2021 ◽  
Vol 8 (4) ◽  
Author(s):  
Anatolii Kuzmin ◽  
Leonid Grekov ◽  
Georgii Veriuzhskyi ◽  
Oleksii Petrov

The paper considers the problem of using images from SAR satellites for the identification of seagoing vessels. It describes the main functions of software and technological complex of the automated monitoring. The system is operated with utilizing space images of SAR satellites Sentinel 1A (B). The algorithmic part, which implements the detection on the sea surface the marks associated with ships, is described in details. To reduce the impact of speckle-noise, the image is pre-processed with the improved Lee-filter. Further processing lies in using an adaptive threshold algorithm that provides detection for each local background fragment of the image the unusually bright pixels, at the same time the algorithm provides a constant probability of error. By solving a nonlinear equation, for each position of the background window the algorithm finds the threshold brightness value and then all pixels above this value are considered vessels. In advance the evaluation of parameters of statistical distribution of pixels’ brightness is performed for each position of the background window. K-mean is used for such distribution. The selected bright pixels are combined into compact groups and their size and coordinates are being determined. The obtained results are compared with the data of the AIS, Automatic Identification System of ships, and the results are displayed on a cartographic basis.

2021 ◽  
Vol 9 (2) ◽  
pp. 180
Author(s):  
Lei Du ◽  
Osiris A. Valdez Banda ◽  
Floris Goerlandt ◽  
Pentti Kujala ◽  
Weibin Zhang

Ship collision is the most common type of accident in the Northern Baltic Sea, posing a risk to the safety of maritime transportation. Near miss detection from automatic identification system (AIS) data provides insight into maritime transportation safety. Collision risk always triggers a ship to maneuver for safe passing. Some frenetic rudder actions occur at the last moment before ship collision. However, the relationship between ship behavior and collision risk is not fully clarified. Therefore, this work proposes a novel method to improve near miss detection by analyzing ship behavior characteristic during the encounter process. The impact from the ship attributes (including ship size, type, and maneuverability), perceived risk of a navigator, traffic complexity, and traffic rule are considered to obtain insights into the ship behavior. The risk severity of the detected near miss is further quantified into four levels. This proposed method is then applied to traffic data from the Northern Baltic Sea. The promising results of near miss detection and the model validity test suggest that this work contributes to the development of preventive measures in maritime management to enhance to navigational safety, such as setting a precautionary area in the hotspot areas. Several advantages and limitations of the presented method for near miss detection are discussed.


2019 ◽  
Vol 73 (1) ◽  
pp. 92-114 ◽  
Author(s):  
Jan Šafář ◽  
Alan Grant ◽  
Paul Williams ◽  
Nick Ward

The Very High Frequency (VHF) Data Exchange System (VDES) is a new radio communication system being developed by the international maritime community, with the principal objectives to safeguard existing Automatic Identification System (AIS) core functions and enhance maritime communication applications, based on robust, efficient and secure data transmission with wider bandwidth than the AIS. VDES is also being considered as a potential component of the R-mode concept, where the same signals used for communication are also used for ranging, thus mitigating the impact of disruptions to satellite positioning services. This paper establishes statistical performance bounds on the ranging precision of VDES R-mode, assuming an additive white Gaussian noise propagation channel. Modified Cramér-Rao bounds on the pseudorange estimation error are provided for all waveforms currently proposed for use in terrestrial VDES communications. These are then used to estimate the maximum usable ranges for AIS/VDES R-mode stations. The results show that, under the assumed channel conditions, all of the new VDES waveforms provide better ranging performance than the AIS waveform, with the best performance being achieved using the 100 kHz bandwidth terrestrial VDE waveforms.


2021 ◽  
Vol 9 (2) ◽  
pp. 145
Author(s):  
Martin Svanberg ◽  
Henrik Holm ◽  
Kevin Cullinane

This paper assesses the impact of a major disruptive event at the port of Gothenburg, Scandinavia’s largest container port. Automatic Identification System (AIS) data is analyzed, in combination with official port statistics on container handling in the four main container ports in Sweden, from 2014–2018. Particular attention is paid to the relationship between container volumes handled and calculated performance metrics at the specific times of the intense labour dispute at the port of Gothenburg during the periods Q2 (2016) and Q4 (2016)–Q2 (2017). The paper concludes that the decline in container volumes handled at Gothenburg over the period is specifically due to fewer ships calling at the port following each of the intense periods of the labour dispute. It is also concluded that the effect on competitor ports in the region were significant in terms of both increased volumes of gateway container traffic and the resulting short-term and medium term impacts on both port user profiles and port efficiency levels.


Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6559
Author(s):  
Krzysztof Naus ◽  
Katarzyna Banaszak ◽  
Piotr Szymak

Mounting offshore renewable energy installations often involves extra risk regarding the safety of navigation, especially for areas with high traffic intensity. The decision-makers planning such projects need to anticipate and plan appropriate solutions in order to manage navigation risks. This process is referred to as “environmental impact assessment”. In what way can these threats be reduced using the available Automatic Identification System (AIS) tool? This paper presents a study of the concept for the methodology of an a posteriori vessel traffic description in the form of quantitative and qualitative characteristics created based on a large set of historical AIS data (big data). The research was oriented primarily towards the practical application and verification of the methodology used when assessing the impact of the planned Offshore Wind Farm (OWF) Baltic II on the safety of ships in Polish Marine Areas, and on the effectiveness of navigation, taking into account the existing shipping routes and customary and traffic separation systems. The research results (e.g., a significant distance of the Baltic II from the nearest customary shipping route equal to 3 Nm, a small number of vessels in its area in 2017 amounting to only 930) obtained on the basis of the annual AIS data set allowed for an unambiguous and reliable assessment of the impact of OWFs on shipping, thus confirming the suitability of the methodology for MREI spatial planning.


2005 ◽  
Vol 58 (1) ◽  
pp. 17-30
Author(s):  
Martha Grabowski ◽  
Hemil Dhami

An Automatic Identification System (AIS) was implemented in the St. Lawrence Seaway during 2003. This paper reports the results of a trial conducted pre- and post-AIS implementation to examine the impact of AIS adoption in a safety-critical system. Analysis of the impact on three types of operators, ship's masters, mates and shore-based traffic management system operators showed that overall AIS significantly improved voyage plan monitoring, contributed to improved monitoring vigilance and offered significant aid to decision making. Recommendations include follow-on studies to include a steady state evaluation of the technology impact once the system is mature and a broadening of the pool of subjects to include a less experienced, more international and less well educated group of operators.


2019 ◽  
Vol 9 (16) ◽  
pp. 3319 ◽  
Author(s):  
Wahyudi Hasbi ◽  
Kamirul ◽  
Mohammad Mukhayadi ◽  
Udo Renner

In this paper, a study on the impact of changing the space-based Automatic Identification System (AIS) monopole antenna orientation on its message reception performance in orbit has been conducted. The study has been carried out by maneuvering the attitude of LAPAN-A2, an equatorial orbiting microsatellite with AIS antenna fixedly mounted on the satellite’s body, into the desired orientation. Based on the analysis of the datasets collected during the maneuver, the orientation of AIS monopole antenna 45° toward its flight direction increases the overall detection performance of the AIS message, including class A ship to 208.80% and also class B ships to 175.93%. This orientation also increases the detection of AIS messages in ocean areas having low detection probability due to AIS signal collision. The result of this research could become a reference in order to specify AIS antenna position and orientation in a small satellite carrying a space-based AIS system for maritime surveillance & monitoring purposes.


Author(s):  
I. Putu Sindhu Asmara ◽  
Eiichi Kobayashi ◽  
Ketut Buda Artana ◽  
Agoes A. Masroeri ◽  
Nobukazu Wakabayashi

This paper proposes a simulation-based method to estimate collision risk for a ship operating in a two-lane canal. According to rule 9 of the Colreg-72 navigation rules, in a narrow canal, a vessel shall keep as near to the wall that lies on its starboard side. However, a busy harbor entered through a narrow canal still presents impact hazards. Certain conditions in a two-lane canal, such as a head-on situation in the straight part of the canal during an overtaking maneuver and large curvature of a turning maneuver in the bend part of the canal, could lead to accidents. In the first condition, the ship alters its own course to the port side to overtake another ship in the same lane but the course altered is too large and hits the wall of the canal. In the second condition, the target ship may take an excessively large turn on the bend part of the canal, causing collision with the ship on the opposite lane. Collision risk is represented as the risk of damage to the ship structure and includes the probability of impact accident and severity of structural damage. Predictions of collision probabilities in a two-lane canal have been developed based on a simulation of ship maneuvering using a mathematical maneuvering group (MMG) model and automatic identification system (AIS) data. First, the propeller revolution and rudder angle of the subject ship are simulated to determine safe trajectories in both parts of the canal. Second, impact accidents are simulated for both conditions. The ship’s speed, and current and wind velocity are randomly simulated based on the distribution of the AIS and environment data for the research area. The structural consequences of the impact accident are measured as collision energy losses, based on the external dynamics of ship collision. The research area of the two-lane canal is located at the Madura Strait between the Java and Madura islands in East Java of Indonesia, as shown by the red line in Figure 1. A project for developing a new port and dredging a new two-lane canal to facilitate an increase in the number of ship calls is currently underway in the research area. Figure 1 shows the ships’ trajectories plotted using the AIS data as on January 1, 2011. The trajectories are mostly seen to be coming out of the canal, confirming that it is shallow and needs to be dredged.


2021 ◽  
Vol 11 (11) ◽  
pp. 5015
Author(s):  
Andrej Androjna ◽  
Marko Perkovič ◽  
Ivica Pavic ◽  
Jakša Mišković

This paper takes a close look at the landscape of the Automatic Identification System (AIS) as a major source of information for maritime situational awareness (MSA) and identifies its vulnerabilities and challenges for safe navigation and shipping. As an important subset of cyber threats affecting many maritime systems, the AIS is subject to problems of tampering and reliability; indeed, the messages received may be inadvertently false, jammed, or intentionally spoofed. A systematic literature review was conducted for this article, complemented by a case study of a specific spoofing event near Elba in December 2019, which confirmed that the typical maritime AIS could be easily spoofed and generate erroneous position information. This intentional spoofing has affected navigation in international waters and passage through territorial waters. The maritime industry is neither immune to cyberattacks nor fully prepared for the risks associated with the use of modern digital systems. Maintaining seaworthiness in the face of the impact of digital technologies requires a robust cybersecurity framework.


2021 ◽  
Vol 2021 (1) ◽  
pp. 685396
Author(s):  
Will Jeffery ◽  
Claire Roberts ◽  
Zhelini Sivanesan

Abstract In recent decades, industrial activity in the marine environment has dramatically increased. Dense offshore infrastructure combined with an increase in shipping activity creates a complex blend of potential oil pollution and environmental risk. Over the last year, CGG Satellite Mapping, supported by the European Space Agency's business applications, Oil Spill Response Limited and key oil and gas companies, created and managed a SeaScope monitoring demonstration service. SeaScope confirms the presence or absence of slicks around infrastructure; reports on the integrity of operations based on slicks observed; identifies the potential origins of pollution slicks or permitted discharge; and has the ability to distinguish between pollution and natural seepage by using routine satellite monitoring. This paper describes how advances in Earth observation radar combined with AIS (Automatic Identification System), metocean data and experts trained in the interpretation of offshore satellite imagery, can be used to regularly monitor sea surface oil slicks and notify offshore operators of anomalous events within the vicinity of offshore infrastructure and high density shipping areas.


2012 ◽  
Vol 19 (1) ◽  
pp. 49-66 ◽  
Author(s):  
Alan Grant ◽  
George Shaw ◽  
Nick Ward

Abstract The General Lighthouse Authorities of the United Kingdom and Ireland (GLA) provide marine Aids-to-Navigation (AtoNs) for the benefit and safety of all mariners within their waters. These AtoNs include traditional lighthouses, buoys and various radionavigation systems. It is recognised that GPS, or more generally Global Navigation Satellite Systems (GNSS), have become the primary means of obtaining Position, Navigation and Timing (PNT) information at sea. Mariners may have come to believe that GPS is infallible, yet it is known to be vulnerable to solar activity, interference and system failures. The Sun continuously releases random bursts of energy and highly charged particles. The impact of these emissions on the Earth is known as space weather. Bursts of electromagnetic energy can result in radio blackouts; bursts of high energy particles can increase ionising radiation and affect space craft performance; and bursts of magnetised plasma can result in the degradation and potential loss of radionavigation signals on Earth. The amount of solar activity is linked with the natural sunspot cycle, which shows the number of sunspots peak approximately every 11 years, with the next peak due in 2013. Sunspots occur almost continuously, but normally give rise to weak solar events that generally go by unnoticed. However significant storms can occur at any time and as we approach peak activity, the number of space weather events will increase. AtoNs generally report their position using radio systems, whether through the Automatic Identification System (AIS), public networks or dedicated links; and often use GNSS to calculate their position and to obtain timing information. Mariners use GNSS for PNT information; with this information integrated into many different bridge systems. Powerful solar storms can affect GNSS performance and the reception of their signals, which may lead to different correlated events, both on and off the ship. During very extreme and very rare storms, national power systems may be switched off to protect the infrastructure which would clearly affect those services relying on mains power without backup. This paper reports the output of a study into the potential effects of space weather on GLA AtoN service provision and presents mitigating actions, where appropriate. The outcome of this study will help the GLA to continue to provide the highest level of AtoN availability, helping to ensure the safety of all mariners.


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