V. Frishfelds, J. She, Jens Murawski, J. W. Nielsen
: Maritime information services supporting European agencies such as the FRONTEX require European ‐ wide forecast solutions. Following a consistent approach, regional and global forecasts of the sea surface conditions from Copernicus Marine Service and national met ‐ ocean services are aggregated in space and time to provide a European ‐ wide forecast service on a common grid for the assistance of Search and Rescue operations. The best regional oceanographic model solutions are selected in regional seas with seamless transition to the global products covering the Atlantic Ocean. The regional forecast models cover the Black Sea, Mediterranean Sea, Baltic Sea, North Sea and combine the North Sea – Baltic Sea at the Danish straits. Two global models have been added to cover the entire model domain, including the regional models. The aggregated product is required to have an update frequency of 4 times a day and a forecasting range of 7 days, which most of the regional models do not provide. Therefore, smooth transition in time, from the shorter time ‐ range, regional forecast models to the global model with longer forecast range are applied. The set of parameter required for Search and Rescue operations include sea surface temperature and currents, waves and winds. The current version of the aggregation method was developed for surface temperature and surface currents but it will be extended to waves in latter stages. The method relies on the calculation of aggregation weights for individual models. For sea surface temperature (SST), near real ‐ time satellite data at clear ‐ sky locations for the past days is used to determine the aggregation weights of individual forecast models. A more complicated method is to use a weighted multi ‐ model ensemble (MME) approach based on best forecast features of individual models and possibly including near real time observations. The developed method explores how satellite observations can be used to assess spatially varying, near real time weights of different forecasts. The results showed that, although
{"title":"Aggregating Sea Surface Hydrodynamic Forecasts From Multi-Models for European Seas","authors":"V. Frishfelds, J. She, Jens Murawski, J. W. Nielsen","doi":"10.12716/1001.17.03.04","DOIUrl":"https://doi.org/10.12716/1001.17.03.04","url":null,"abstract":": Maritime information services supporting European agencies such as the FRONTEX require European ‐ wide forecast solutions. Following a consistent approach, regional and global forecasts of the sea surface conditions from Copernicus Marine Service and national met ‐ ocean services are aggregated in space and time to provide a European ‐ wide forecast service on a common grid for the assistance of Search and Rescue operations. The best regional oceanographic model solutions are selected in regional seas with seamless transition to the global products covering the Atlantic Ocean. The regional forecast models cover the Black Sea, Mediterranean Sea, Baltic Sea, North Sea and combine the North Sea – Baltic Sea at the Danish straits. Two global models have been added to cover the entire model domain, including the regional models. The aggregated product is required to have an update frequency of 4 times a day and a forecasting range of 7 days, which most of the regional models do not provide. Therefore, smooth transition in time, from the shorter time ‐ range, regional forecast models to the global model with longer forecast range are applied. The set of parameter required for Search and Rescue operations include sea surface temperature and currents, waves and winds. The current version of the aggregation method was developed for surface temperature and surface currents but it will be extended to waves in latter stages. The method relies on the calculation of aggregation weights for individual models. For sea surface temperature (SST), near real ‐ time satellite data at clear ‐ sky locations for the past days is used to determine the aggregation weights of individual forecast models. A more complicated method is to use a weighted multi ‐ model ensemble (MME) approach based on best forecast features of individual models and possibly including near real time observations. The developed method explores how satellite observations can be used to assess spatially varying, near real time weights of different forecasts. The results showed that, although","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84927176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: Vessel Traffic Services (VTS) are to improve the safety and efficiency of vessel traffic and to protect the marine environment by interacting with the ship’s traffic in monitored coastal areas. Today, VTS operators are maritime professionals with nautical education from a university or technical college and practical experience on board. This experience and nautical background is a key element of the work as a VTS operator. It is to support understanding the daily work. The current situation in the maritime domain is undergoing substantial changes, such as introducing new technologies, implementing the e ‐ Navigation concept based on sustainable digitalization and ambitions to realize unmanned and autonomous shipping. This paper will present preliminary results of a pilot study conducted in VTS Centres along the coast of North and Baltic Sea and discuss selected options and opportunities for education and training of future VTS operators, which might not have the advantage of practical sea experience anymore.
{"title":"From Ship to Shore – Studies Into Potential Practical Consequences of Autonomous Shipping on VTS Operation and Training","authors":"T. Janßen, M. Baldauf, G. Claresta","doi":"10.12716/1001.17.02.15","DOIUrl":"https://doi.org/10.12716/1001.17.02.15","url":null,"abstract":": Vessel Traffic Services (VTS) are to improve the safety and efficiency of vessel traffic and to protect the marine environment by interacting with the ship’s traffic in monitored coastal areas. Today, VTS operators are maritime professionals with nautical education from a university or technical college and practical experience on board. This experience and nautical background is a key element of the work as a VTS operator. It is to support understanding the daily work. The current situation in the maritime domain is undergoing substantial changes, such as introducing new technologies, implementing the e ‐ Navigation concept based on sustainable digitalization and ambitions to realize unmanned and autonomous shipping. This paper will present preliminary results of a pilot study conducted in VTS Centres along the coast of North and Baltic Sea and discuss selected options and opportunities for education and training of future VTS operators, which might not have the advantage of practical sea experience anymore.","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87297071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Valter Suban, Urban Pegan, Jure DemŁar, Danijela Tuljak-Suban, M. Perkovič, V. Bandelj
: Should an oil spill of tier III magnitude occur in the Northern Adriatic, there is a high probability that the oil will reach and pollute the surrounding coastline. Therefore, it is vital to conduct coastal vulnerability studies to develop priority plans and coastal vulnerability maps to help first responders protect the coastline. As there is no common contingency plan for oil spills in the Northern Adriatic
{"title":"Socio-Economic Factors in the Event of an Oil Spill in the North Adriatic","authors":"Valter Suban, Urban Pegan, Jure DemŁar, Danijela Tuljak-Suban, M. Perkovič, V. Bandelj","doi":"10.12716/1001.17.03.20","DOIUrl":"https://doi.org/10.12716/1001.17.03.20","url":null,"abstract":": Should an oil spill of tier III magnitude occur in the Northern Adriatic, there is a high probability that the oil will reach and pollute the surrounding coastline. Therefore, it is vital to conduct coastal vulnerability studies to develop priority plans and coastal vulnerability maps to help first responders protect the coastline. As there is no common contingency plan for oil spills in the Northern Adriatic","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85279767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Koen van de Merwe, S. Mallam, Ø. Engelhardtsen, Salman Nazir
: Automation transparency is a means to provide understandability and predictability of autonomous systems by disclosing what the system is currently doing, why it is doing it, and what it will do next. To support human supervision of autonomous collision avoidance systems, insight into the system’s internal reasoning is an important prerequisite. However, there is limited knowledge regarding transparency in this domain and its relationship to human supervisory performance. Therefore, this paper aims to investigate how an information processing model and a cognitive task analysis could be used to drive the development of transparency concepts. Also, realistic traffic situations, reflecting the variation in collision type and context that can occur in real ‐ life, were developed to empirically evaluate these concepts. Together, these activities provide the groundwork for exploring the relation between transparency and human performance variables in the autonomous maritime context
{"title":"Operationalising Automation Transparency for Maritime Collision Avoidance","authors":"Koen van de Merwe, S. Mallam, Ø. Engelhardtsen, Salman Nazir","doi":"10.12716/1001.17.02.09","DOIUrl":"https://doi.org/10.12716/1001.17.02.09","url":null,"abstract":": Automation transparency is a means to provide understandability and predictability of autonomous systems by disclosing what the system is currently doing, why it is doing it, and what it will do next. To support human supervision of autonomous collision avoidance systems, insight into the system’s internal reasoning is an important prerequisite. However, there is limited knowledge regarding transparency in this domain and its relationship to human supervisory performance. Therefore, this paper aims to investigate how an information processing model and a cognitive task analysis could be used to drive the development of transparency concepts. Also, realistic traffic situations, reflecting the variation in collision type and context that can occur in real ‐ life, were developed to empirically evaluate these concepts. Together, these activities provide the groundwork for exploring the relation between transparency and human performance variables in the autonomous maritime context","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82528448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Ship Neural Domain Shape on Safe and Optimal Trajectory","authors":"J. Lisowski","doi":"10.12716/1001.17.01.20","DOIUrl":"https://doi.org/10.12716/1001.17.01.20","url":null,"abstract":"","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81053294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: The present paper is aimed at sharing practical experience of organizing active interaction with Maritime English students of remote groups in conditions of permanent online teaching and learning processes. The authors explore various strategies that can be integrated into the design and development of tailored e ‐ books and tutors’ e ‐ courses to foster high level of Maritime English students’ online interaction. In addition, the use of modern digital tools for the successful running of e ‐ books and e ‐ courses is discussed as well as the role these tools play in promoting atmosphere of interaction to allow students be deeply engaged into learning activities and contribute to genuine discussion. A few aspects considered with regard to the process of designing e ‐ books and e ‐ courses are accessibility of learning materials, integration of design elements, and development of students’ online community, encouraging discussions and application of effective assessment methods. The study examines their experience of teaching Maritime English using Moodle and Zoom platforms. The findings of the study can be useful for educators to promote more interactive online learning.
{"title":"Promoting Active Online Interaction with Maritime English Students","authors":"V. Kudryavtseva, S. Barsuk, O. Frolova","doi":"10.12716/1001.17.03.23","DOIUrl":"https://doi.org/10.12716/1001.17.03.23","url":null,"abstract":": The present paper is aimed at sharing practical experience of organizing active interaction with Maritime English students of remote groups in conditions of permanent online teaching and learning processes. The authors explore various strategies that can be integrated into the design and development of tailored e ‐ books and tutors’ e ‐ courses to foster high level of Maritime English students’ online interaction. In addition, the use of modern digital tools for the successful running of e ‐ books and e ‐ courses is discussed as well as the role these tools play in promoting atmosphere of interaction to allow students be deeply engaged into learning activities and contribute to genuine discussion. A few aspects considered with regard to the process of designing e ‐ books and e ‐ courses are accessibility of learning materials, integration of design elements, and development of students’ online community, encouraging discussions and application of effective assessment methods. The study examines their experience of teaching Maritime English using Moodle and Zoom platforms. The findings of the study can be useful for educators to promote more interactive online learning.","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74805054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: In this work, the routes for inbound / outbound from each berth in the port of Chornomorsk were designed according to the ship’s pilotage plan for navigational purposes. On the basis of the received information, a computer ‐ aided planning of recommended routes for pilotage of all types of vessels, which would call the port of Chornomorsk, was developed. The results of the automatic analysis by the computer program are designed as the matrix of coordinates for inbound / outbound at the port. In order to verify the cybersecurity of the introduced model of automatic planning of the path by the coordinates of trajectory points and using the decision support systems for the automatic control of the parameters of maneuvering by technical methods, radar observations were carried out. After observation the comparing analysis of the accuracy of ship and shore radar systems was done, the methodology of the observations for coastal systems developed. Conducted radar observation of 300 arrivals and 200 departures of vessels from the port of Chornomorsk according to the developed plans for each berth in the port. The recommended routes were integrated into the expanded computer program «Path Planning IS», which made it possible to obtain the matrixes of coordinates of the observations. A comparative analysis of the computer simulation and practical transition of ships in the recommended water area of the port demonstrated that the introduced model is confirmed by the results of the observations. On the basis of the analysis, it is determined that the developed model ensures the cybersecurity of the processes of maneuvering in confined waters.
{"title":"Cybersecurity of the Processes of Manoeuvring in Confined Waters","authors":"Igor Surinov, Dmytro Shumilov Shumilov","doi":"10.12716/1001.17.03.25","DOIUrl":"https://doi.org/10.12716/1001.17.03.25","url":null,"abstract":": In this work, the routes for inbound / outbound from each berth in the port of Chornomorsk were designed according to the ship’s pilotage plan for navigational purposes. On the basis of the received information, a computer ‐ aided planning of recommended routes for pilotage of all types of vessels, which would call the port of Chornomorsk, was developed. The results of the automatic analysis by the computer program are designed as the matrix of coordinates for inbound / outbound at the port. In order to verify the cybersecurity of the introduced model of automatic planning of the path by the coordinates of trajectory points and using the decision support systems for the automatic control of the parameters of maneuvering by technical methods, radar observations were carried out. After observation the comparing analysis of the accuracy of ship and shore radar systems was done, the methodology of the observations for coastal systems developed. Conducted radar observation of 300 arrivals and 200 departures of vessels from the port of Chornomorsk according to the developed plans for each berth in the port. The recommended routes were integrated into the expanded computer program «Path Planning IS», which made it possible to obtain the matrixes of coordinates of the observations. A comparative analysis of the computer simulation and practical transition of ships in the recommended water area of the port demonstrated that the introduced model is confirmed by the results of the observations. On the basis of the analysis, it is determined that the developed model ensures the cybersecurity of the processes of maneuvering in confined waters.","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80273663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Martelli, Srdjan ŽuŁkin, R. Zaccone, Igor Rudan
: Groundings and collisions still represent the highest percentage of marine accidents despite the current attention on Maritime Education and Training and the improvement of sensor capability. Most of the time, a collision is caused by a human error with consequences ranging from moderate to severe, with a substantial impact on both environment and life safeguarded at sea. In this paper, a brief statistical data regarding human element as a root cause of marine incidents together with collision regulations misunderstanding is presented as a background chapter. Furthermore, the present work discusses a decision support system architecture to suggest an appropriate action when the risk of a potential collision is detected. The proposed architecture system is based on various modules integrated with proper sensor input data regarding the surrounding navigation area.
{"title":"A COLREGs-Compliant Decision Support Tool to Prevent Collisions at Sea","authors":"M. Martelli, Srdjan ŽuŁkin, R. Zaccone, Igor Rudan","doi":"10.12716/1001.17.02.11","DOIUrl":"https://doi.org/10.12716/1001.17.02.11","url":null,"abstract":": Groundings and collisions still represent the highest percentage of marine accidents despite the current attention on Maritime Education and Training and the improvement of sensor capability. Most of the time, a collision is caused by a human error with consequences ranging from moderate to severe, with a substantial impact on both environment and life safeguarded at sea. In this paper, a brief statistical data regarding human element as a root cause of marine incidents together with collision regulations misunderstanding is presented as a background chapter. Furthermore, the present work discusses a decision support system architecture to suggest an appropriate action when the risk of a potential collision is detected. The proposed architecture system is based on various modules integrated with proper sensor input data regarding the surrounding navigation area.","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87576480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: A seafarer’s personality is based on three distinct stages in the psy chological development of his/her marine self-concept, including self-esteem, i
{"title":"Psychological Internalization of Marine Self-Concept During Studies and on Board","authors":"Saulius Lileikis","doi":"10.12716/1001.17.04.20","DOIUrl":"https://doi.org/10.12716/1001.17.04.20","url":null,"abstract":": A seafarer’s personality is based on three distinct stages in the psy chological development of his/her marine self-concept, including self-esteem, i","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134982650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we consider the possibility of using the radar characteristics under precipitation conditions in order to reduce the echo signal’s negative impact on the object tracking performed by the ship’s radar. Precipitation particles’ size, state (solid or liquid phase), shape, and the factors that determine their combined action play an important role in echo signal formation. The rain particles’ size in comparison with the wavelength of the ship’s radar may contribute to the creation of a larger or smaller noise echo signal on the ship’s radar display. This signal’s power in the Rayleigh scattering area towards the radar is characterized by the effective scattering area. Raindrops represent a combination of randomly located reflectors. Their scattering properties depend on spatial distribution and movement regularity. At the same time, the radar characteristics of clouds with precipitation generated by them can be used in ship radars to determine the intensity of the atmospheric process along the ship’s route. The uncertainty in determining the power attenuation of an electromagnetic wave emitted by a ship’s radar antenna and passing through the precipitation zone can be reduced by the simultaneous use of two wavelengths on which a ship’s radars operate. The presented uncertainty function characterizes a narrow-band polarized scattered signal in regard to radar information about the distance to the sea object and the scatterer's speed. It characterizes the matched multidimensional coherent filter’s properties. This filter provides optimal echo reception against the background of an uncorrelated precipitation echo signal. The matched filter belongs to the class of optimal linear filters according to the criterion of the maximum signalto-noise ratio and is the main element for radar detection devices in the ship radar, which is optimal according to the Neyman-Pearson criteria. Keywords: radar characteristics of precipitation, precipitation intensity, effective scattering area, precipitation particle diameter, dielectric constant, energy attenuation, radio waves, wavelength.
{"title":"Radar Characteristics of Precipitation Affecting the Tracking of Ship’s Radar Objects","authors":"V. Revenko","doi":"10.12716/1001.16.03.10","DOIUrl":"https://doi.org/10.12716/1001.16.03.10","url":null,"abstract":"In this paper, we consider the possibility of using the radar characteristics under precipitation conditions in order to reduce the echo signal’s negative impact on the object tracking performed by the ship’s radar. Precipitation particles’ size, state (solid or liquid phase), shape, and the factors that determine their combined action play an important role in echo signal formation. The rain particles’ size in comparison with the wavelength of the ship’s radar may contribute to the creation of a larger or smaller noise echo signal on the ship’s radar display. This signal’s power in the Rayleigh scattering area towards the radar is characterized by the effective scattering area. Raindrops represent a combination of randomly located reflectors. Their scattering properties depend on spatial distribution and movement regularity. At the same time, the radar characteristics of clouds with precipitation generated by them can be used in ship radars to determine the intensity of the atmospheric process along the ship’s route. The uncertainty in determining the power attenuation of an electromagnetic wave emitted by a ship’s radar antenna and passing through the precipitation zone can be reduced by the simultaneous use of two wavelengths on which a ship’s radars operate. The presented uncertainty function characterizes a narrow-band polarized scattered signal in regard to radar information about the distance to the sea object and the scatterer's speed. It characterizes the matched multidimensional coherent filter’s properties. This filter provides optimal echo reception against the background of an uncorrelated precipitation echo signal. The matched filter belongs to the class of optimal linear filters according to the criterion of the maximum signalto-noise ratio and is the main element for radar detection devices in the ship radar, which is optimal according to the Neyman-Pearson criteria. Keywords: radar characteristics of precipitation, precipitation intensity, effective scattering area, precipitation particle diameter, dielectric constant, energy attenuation, radio waves, wavelength.","PeriodicalId":46009,"journal":{"name":"TransNav-International Journal on Marine Navigation and Safety of Sea Transportation","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82606656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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