International recent issues about ecdis, e navigation and safety at sea  marine navigation and safety of sea transportation

Weintrit e-Navigation Concept

Amato, M Fiorini, S Gallone & G Golino 2 Development of Requirements for Communication Management on Board in the Framework

SELEX - Sistemi Integrati, Rome, Italy

ABSTRACT: The International Maritime Organization (IMO) adopted the following definition of e-

e-Navigation involves the systematic collection, integration, and analysis of maritime information using electronic means, both onboard and ashore This approach enhances navigation from berth to berth and improves related services, ensuring safety and security at sea while also protecting the marine environment.

Navigation systems have evolved significantly, showcasing robust electronic positioning capabilities, often with redundancy for enhanced reliability At the IALA-AISM conference in Cape Town in March 2010, manufacturers in the navigation surveillance market unveiled advanced solid-state products for Vessel Traffic Services (VTS) and Aids to Navigation, indicating a promising new trend in this sector This paper provides an overview of global navigation systems and emerging trends in navigation aids, along with a brief discussion on anticipated developments in the field.

Concerning radars, a clear trend emerged from the last IALA-AISM conference held in Cape Town,

March 2010, where almost all the manufactures companies involved on navigation surveillance market present –at various state of development- solid state products for VTS and Aids to Navigation

The evolution of radar technology has transitioned from microwave tubes, such as klystrons and magnetrons, to solid-state technologies This shift was influenced by the IMO resolution 192(79), which aimed to promote the development of low-power, cost-effective radars by eliminating the requirement for S-band radar to activate RACONS starting in July 2008.

Solid-state radar technology offers a promising solution by utilizing low-power and digital signal processing techniques, effectively reducing clutter displays commonly linked to high-power magnetron-based radars.

A full comparison magnetron versus solid state

The VTS radars, as detailed in [7], demonstrate experimental results using live data to illustrate the clutter filtering and range discrimination capabilities of the solid-state LYRA 50 radar Key advantages of solid-state transmission include extended operational life, graceful degradation, coherent processing, high duty cycles, multi-frequency transmission across a wide bandwidth, elimination of high voltage supply requirements, and compact technology.

This article provides an overview of the current advancements in Global Navigation Satellite Systems (GNSS) and Differential GNSS (DGNSS), as discussed in reference [8] It also highlights the role of radio aids to navigation and introduces a novel application of radar technology for validating aids to navigation (AtoN).

In short, based on the IMO definition, three fundamental elements must be in place as pre-requisite for the e-Navigation These are:

1 worldwide coverage of navigation areas by Elec- tronic Navigation Charts (ENC);

2 a robust and possibly redundant electronic positioning system; and

3 an agreed infrastructure of communications to link ship and shore but also ship and ship

To effectively implement e-Navigation, a robust technical architecture is essential, encompassing shipboard entities, physical links, and shore-based entities, as illustrated in Figure 1.

The e-Navigation concept highlights the key components of a ship's technology environment, which includes the transceiver station, various data sources, and data sinks connected to the station, as well as the Integrated Navigation System (INS).

The Integrated Bridge System (IBS) simplifies the representation of transceiver stations by illustrating them as a single unit, despite the possibility of multiple stations in operation The details concerning the link technology are delineated within the confines of a dotted line, emphasizing the entities involved in this aspect.

Figure 1 e-Navigation architecture Source: IALA e- NAV140 [9]

Shore-based technical e-Navigation services provide essential interfaces for user applications, facilitating connections to physical links and integrating with the overall e-Navigation system architecture Utilizing the principle of encapsulation, which compartmentalizes structural and behavioral elements, these services simplify the technology by separating the user interface from its underlying complexity This approach not only conceals the intricacies of the technology but also allows specialized experts to work concurrently on specific link technologies, as long as the functional interfaces are clearly defined.

For the precise technical structure of the shore- base technical e-Navigation services, the common shore-base e-Navigation system architecture is under development for a future IALA Recommendation

The World Wide Radio Navigation System (WWRNS), which encompasses GNSS, is highlighted as an external system to the e-Navigation architecture that delivers essential position and time information Additionally, the Universal Maritime Data Model is introduced as an abstract representation of the maritime domain.

4 USAGE OF RADAR TO VALIDATE AIDS TO NAVIGATION

Barker suggests enhancing AtoN by incorporating additional information sources, specifically focusing on vessel traffic routing data provided by the Automatic Identification System.

The integration of the Automatic Identification System (AIS) enhances the assessment of Aids to Navigation (AtoN) Onboard vessel radars can be utilized to verify the positioning of buoys and beacons, allowing for near real-time confirmation of the information provided by these aids This capability enables timely alerts for necessary maintenance Additionally, the latest generation of Vessel Traffic Service (VTS) and navigation radars significantly improves target classification, facilitating more effective monitoring and management of navigation aids.

4.1 Identification of buoys by solid state VTS / navigation radars

In this section an example of application of the described system is shown

Navigation buoys can experience drift or malfunction, necessitating a reliable method for detecting their presence and accurate positioning This approach involves sending data to a ground base station to verify the buoy's location against navigation maps Additionally, the method serves maintenance purposes by identifying device failures, such as low battery issues, and utilizes a passive reflector situated on top of the buoy.

Traditional VTS and navigation radars struggle with long-distance classification due to their non-coherent receivers and limited range resolution Typically, navigation radars using magnetrons are optimized for medium to high ranges, enhancing navigational safety by employing medium-long pulses (30-75 m), which unfortunately results in inadequate range discrimination.

New generation solid state radars permits to un- couple resolution from transmitted pulse length by using a coherent receiver and long coded pulses

Motz, E Dalinger, S Hửckel & C Mann 3 Advanced Maritime Technologies to Support Manoeuvring in Case of Emergencies –

Fraunhofer Research Institute for Communication, Information Processing and Ergonomics, FKIE, Wachtberg, Germany

The current separation of communication and navigational systems on ships does not align with the International Maritime Organization's (IMO) e-navigation concept, which emphasizes the integration of all relevant information for safe navigation Hydrographic, meteorological, and safety-related data are often presented without adequate filtering, primarily through communication equipment or printouts A task-oriented integration of this information on navigational displays can significantly aid officers in decision-making and enhance safety Central to this integration is the IMO's Integrated Navigation System (INS) concept, which advocates for a modular approach to presenting information based on situational needs To facilitate this, a communication management concept has been developed, informed by an Applied Cognitive Work Analysis (ACWA) that identifies design requirements based on operators' cognitive processes This paper outlines the communication management concept and provides an initial description of maritime communication, serving as a foundation for establishing requirements within the e-navigation framework.

A task-oriented integration and presentation of navigational information on displays ensures that officers have fast, reliable, consistent, and easily interpretable data at their disposal This approach supports decision-making and enhances navigation safety The revised performance standards for Integrated Navigation Systems (INS) introduced by the IMO in 2007, based on a modular concept established in 2008, provide a foundation for further integration of onboard information.

Modular Integrated Navigation Systems (INS) are designed to meet the updated International Maritime Organization (IMO) performance standards, integrating validated data from multiple sensors and functions These systems enable the effective presentation of information across various displays tailored to specific tasks.

Implementing a communication management system on the bridge is essential for assisting mariners in effectively completing communication tasks and providing vital information to the Integrated Navigation System (INS).

The INS aims to enhance safety by integrating navigational information, allowing it to function as a cohesive system rather than standalone equipment on ships, in accordance with SOLAS Chapter V regulation 19 According to the IMO performance standards, this integration can be implemented through a modular approach, accommodating both comprehensive and partial integrations of navigational systems.

An Integrated Navigation System (INS) enhances navigation safety by offering integrated and augmented functionalities to mitigate geographic, traffic, and environmental hazards Designed to be user-friendly for specific tasks within particular contexts, an INS encompasses essential navigational tasks, including route planning and route monitoring.

Collision avoidance systems are crucial components of integrated navigation systems, which encompass various sources, data, and displays According to performance standards, an Inertial Navigation System (INS) is recognized if it successfully performs at least two of the essential navigational tasks or functions.

Effective alert management is essential for the Inertial Navigation System (INS), alongside the display of navigation control data for manual operation Additionally, various navigational tasks can be incorporated into the INS for enhanced functionality.

The following six navigational tasks are described in detail within the performance standards for INS (IMO, 2007b):

Effective route planning and monitoring are essential for optimizing navigation control data and ensuring collision avoidance Alert management and status display features enhance operational efficiency The scope of an Integrated Navigation System (INS) can vary based on the number and type of tasks and functions it encompasses According to performance standards set by the IMO (2007b), the application of requirements for INS can be tailored to the specific integrated tasks and functionalities.

The integration of information from communication systems into navigational displays is guided by INS performance standards, which facilitate the inclusion of tidal, current, weather, and ice data, as well as other relevant information for navigation control and route monitoring For route planning, the INS enables the drafting and refinement of route plans using available meteorological information, while also allowing the display of essential route-related data, such as SAR maneuvers and NAVTEX, on the chart display for effective route monitoring.

The modular bridge concept features distinct operational/functional and sensor/source modules, ensuring a clear separation between task-oriented operational requirements and the presentation of information regarding equipment and systems Additionally, it delineates specific technical requirements for sensors The interfacing module facilitates connections and data exchange with other systems.

Based on the modular bridge concept the design of future systems becomes flexible, task and situation orientated

To develop an effective communication management concept for ship bridges, an analysis of the existing communication infrastructure and procedures on board was performed A literature review focused on GMDSS-required systems and supplementary technology was conducted Additionally, interviews with potential users helped identify key aspects for determining user requirements related to communication management and the integration of information transfer from communication systems into navigational systems.

Based on this information a concept for communication management was developed with the following objectives:

Presentation of information received via communication systems on the navigational displays

(INS) of the ships bridge

User-selectable automatic filtering and processing of information to prevent information overload

Provision of source and channel management (selection of best connection according to criteria, e.g., content, integrity, costs)

Increased availability and reliability due to efficient use of different communication channels

Figure 2 provides a content-related visualisation of the communication management concept

An INS task for "Communication Management" involves organizing information from various communication systems based on its type This organized information is then directed to navigational and other bridge systems or made available upon request The resulting information clusters correspond to the types identified through an analysis of the communication infrastructure.

The communication management system enhances data acquisition and communication by offering effective source and channel management This allows for the selection of data communication connections based on specific criteria such as integrity, content, and costs These criteria can be adjusted through the human-machine interface of the communication management system.

The communication management system evaluates and organizes data based on information type, enabling efficient processing and filtering This approach updates previously received information, prevents data duplication, and ensures the selection of relevant information tailored to the specific vessel type and route.

Ziebold, Z Dai, T Noack & E Engler

A Harmonized ENC Database as a Foundation of Electronic Navigation

Bergmann 6 Navigation Safety Assessment in the Restricted Area with the Use of ECDIS

Jeppesen, a Boeing Company, Frankfurt AmMain Area, Germany

The future of electronic navigation is centered on enhancing ECDIS through the integration of supplementary data streams, such as AIS and real-time tide information While these elements are crucial, it is essential to emphasize that the ENC data layer serves as the foundational component for enabling advanced data visualization.

The current emphasis on ENC production is limited in terms of scale bands and datum codes, which, while effective for meeting the IMO ECDIS mandate, does not adequately prepare future mariners for their electronic navigation needs As discussions within the IMO e-Navigation and IALA e-Navigation Committee progress, they are aligning with the new IHO S-100 and S-101 standards, along with the developing S-10X series The hydrographic community must consider these developments to enhance safety in electronic navigation, especially in an evolving maritime landscape characterized by larger vessels and increased traffic in challenging navigational areas.

The paper will focus on the following topics:

– The ENC data layer as the basis of electronic navigation,

– Closing gaps and overlaps in ENC coverage by adjusting cell boundaries,

– Moving from a cell based data structure to a seamless database structure,

– Integration of Scale-Independent and Scale-Dependent objects,

– Adaption of harmonized and flexible data models – an S-10X outlook,

– Enabling integration of advanced data streams – an e-NAV outlook

Table 1 IMO Timetable for ECDIS carriage requirements – from “ECDIS – What you need to know”, Jeppesen

Key components of these objectives are the standards for the “Electronic Nautical Charts”

The current S-57 standard defines Electronic Navigational Charts (ENCs) as the sole vector data sets that enable the operation of an Electronic Chart Display and Information System (ECDIS) in its designated mode This functionality is essential for performing primary navigation using electronic systems.

IMO has looked at the Hydrographic Offices

(HOs) around the world, represented by IHO, to provide adequate ENC coverage before adapting the

ECDIS mandate The IHO has confirmed to IMO-

MSC and IMO-NAV that by 2012 adequate ENC coverage will be available

All of the above highlights that both IMO as well as IHO see ENCs in ECDIS as the foundation and primary data set for electronic navigation

Following its initiative on ECDIS, IMO has launched another initiative: “e-Navigation” The “e-

The "Navigation Correspondence Group" focuses on "enhanced Navigation," which aims to integrate shore-based and ship-based systems and data streams to improve situational awareness throughout all phases of sailing, thereby further enhancing navigational safety Key concepts discussed include integrated AIS (Automated Identification System), various system overlays onboard, and automated information exchange between shore and ship, such as sharing Vessel Traffic System (VTS) data.

Recent collaborations between the IMO e-Navigation development and the IALA e-Navigation Committee have led to significant progress in harmonizing electronic navigation initiatives Various working groups have focused on aligning the efforts of IHO, IALA, and IMO to shape the future of enhanced navigation During these discussions, stakeholders, including industry representatives and experts, reached a consensus on utilizing the new IHO S-100 and S-101 standards, along with the emerging S-10X series, as foundational elements for developing new marine data models.

The IHO's "GI-Registry," or Geographical Information Registry, plays a crucial role in harmonizing GIS data models within the maritime industry This development establishes a unified platform for integrated systems, enabling the hydrographic community to proactively prepare for the future of electronic navigation By doing so, it aims to enhance navigation safety amid increasing maritime traffic and the challenges posed by larger vessels in complex navigational environments.

The evolving concept of e-Navigation emphasizes the necessity for continuous innovation in navigation practices, highlighting the need for a transformation in performance standards Current ECDIS performance standards are seen as a barrier to innovation, as their update and certification processes do not align with the requirements of modern e-Navigation.

A new concept is being developed to create a framework that integrates and harmonizes multiple data streams, enhancing Situational Awareness in increasingly complex environments.

The development of onboard and onshore systems is essential to enhance navigation safety and security, addressing the critical needs of coastal administrations Additionally, these advancements will significantly improve voyage efficiency, creating a strong demand among ship owners and operators for their implementation.

The dominant argument unifying all stakeholders to move towards common structures and towards the

The IHO-originated model highlights the imminent implementation of S-100 and its related standards, which will soon come to fruition Consequently, Electronic Navigational Charts (ENCs) will adopt this data structure, along with associated data streams such as Inland ENCs and Marine Information Overlays As all stakeholders recognize that the ENC layer serves as the cornerstone for advanced navigational systems, it is a logical progression to align other data streams with this foundational element This development further reinforces the significance of ENCs in modern navigation.

Hydrographic Vector Chart Data Layers, are the necessary ingredients for any navigational display now and in the foreseeable future

The traditional hydrographic work to create the necessary tools for mariners to navigate safely is utilizing classic cartographic concepts

An early chart from the year 1603 illustrates that cartographic art work is used to allow the knowl- edgeable navigator gaining sufficient information for a safe passage

In the traditional paper world, the evolution of information transport has spanned centuries, establishing best practices Today, the paper charts utilized by Hydrographic Offices globally are often exquisite artworks, meticulously designed to assist in maritime navigation.

The concept of electronic navigation began with the use of Raster Charts, notably the Admiralty Raster Chart Service (ARCS) However, stakeholders soon recognized that raster charts limited the full potential of electronic navigation Vector cartography emerged as a superior alternative, offering enhanced situational awareness through data links, full zoom capabilities without distortion, and various other advantages Initially, the first vector charts were developed without regulation, but the introduction of Electronic Navigational Charts (ENCs) has established them as the official electronic navigational charts on SOLAS class ships.

The current Electronic Navigational Charts (ENCs), based on the S-57 standard, are limited in scope as they operate on a "cell-based" system, focusing on defined rectangular areas rather than providing a comprehensive Hydrographic Database Consequently, what is available is merely a collection of related charts housed in a central data repository Hydrographic Offices (HOs) attempt to harmonize these cells to achieve a seamless appearance, but the limitations of the existing system hinder true integration and functionality.

The ECDIS display often presents a "chart by chart" view, making effective harmonization challenging due to the focus on a "scale band" concept Hydrographic data is crafted by cartographers for optimal use at specific zoom levels within individual cells, necessitating harmonization not only within the same scale but also across different scale bands This complexity often leads to the omission of necessary harmonization efforts, resulting in data and display conflicts as vessels navigate and zoom in or out, transitioning between independently developed scale bands.

The chart-centric ENC production process significantly enhances navigation; however, it struggles to improve situational awareness for mariners while minimizing confusion, even when managed by a single Hydrographic Office (HO) As SOLAS vessels often traverse international waters, ECDIS systems must handle data from various countries, leading to increased complexity This complexity can result in problems such as overlapping data, data gaps, and mismatched adjacent cells.

Where “Regional ENC Coordination Centers” (RENCs) are used, those RENCs are also trying to help harmonizing the ENCs, but of limited success, given the complexity of the task

Pietrzykowski & M Wielgosz 7 Increasing Maritime Safety: Integration of the Digital Selective Calling VHF Marine

Maritime University of Szczecin, Szczecin, Poland

This paper analyzes the critical vessel safety parameters utilized in the ECDIS system for navigating restricted areas, identifying essential factors that ensure safe navigation in such waters.

The ship domain function, derived from safety parameters in the ECDIS system, can enhance navigation decision support systems by integrating ECDIS data This new functionality can improve overall system performance, including networking capabilities Additionally, alarms related to navigational functions play a crucial role in signaling significant events that impact navigation safety.

The fourth division categorizes alarms based on their scope of activities, which refers to the functions of alarms linked to various types of threats This classification includes antigrounding alarms, route alarms associated with the ship's path, target or radar alarms, area alarms, other types of alarms, AIS alarms, and alarms related to the scale and type of charts.

Experiments at the Maritime University of Szczecin during ECDIS courses reveal that participants often underutilize the system's capabilities and struggle with interpreting alarms and indications This challenge arises from the distinct differences between working with Electronic Navigational Charts (ENC) and traditional paper or raster charts.

A lack of understanding of ENC content interpretation principles by ECDIS operators leads to underutilization of the system and inconsistent application compared to traditional paper charts This issue arises because navigator training predominantly relies on paper charts, where the user is solely responsible for interpreting the chart's contents To enhance the effective use of ECDIS systems, it is essential to incorporate broader training on ENC usage for navigators.

Alarm type Activation/ Source Scope of Priority deactivation activities

_ a) alarm deactiv equipment, anti- basic impossible sources grounding _ b) indication deactiv system route other possible

Effective utilization of the system can be enhanced through the strategic division and allocation of alarms and indications This includes essential alarms necessary for safe voyage monitoring, along with supplementary alarms that provide additional support.

These criteria and the classifications of alarms are summarized in Table 1

An analysis of alarms and indications was conducted based on the ECDIS scope of activities, focusing on criterion 4 This analysis led to a proposed division of alarms into basic and other categories, as outlined in criterion 5.

The alarms in question are presented in Table 2., categorized by the groups of alarms identified in the ECDIS NaviSailor 3000i system

Table 2 Groups of alarms according to the presented criteria (see Table 1)

Group of Location Criterion alarms/ (ECDIS 1 2 3 4 5 indications NaviSailor

3000i) _ antigroun- monitoring/ a, b *) a, b, c *) b a a ding alarms nav alarms system a, b *) a, b, c *) b a a _ route monitoring/ a a, b *) a, b *) a, b *) a, b *) alarms route mon system a a, b *) a, b *) a, b *) a, b *) _ target/ targets/ a a, b *) a, b *) a, c *) a, b *) alarms ARPA system a a, b *) a, b *) a, c *) a, b *) _ areas/ monitoring a a b d a basic areas nav alarms

_ areas/ monitoring a a b d b add areas nav alarms

_ other monitoring/ a a b e a, b alarms nav alarms system a a b e a, b config a a b e a, b _

AIS alarms _ chart system a, b * b b g a, b *) alarms charts a, b * b b g a, b *) monitoring a, b * b b g a, b *) _

*) due to the diversity of alarms in the group, it was necessary to assign some of them to more than one group according to the criterion

The group of "Antigrounding Alarms" contains: a) Nav danger, b) Safety contour changed, c) An- chor watch, c) Safety contour, e) Safety depth, f) Ag monitoring off, g) Safety scale changed

The group of "Route Alarms" contains: a) Off chart, b) End of route, c) Out of XTE, d) Behind schedule, e) Ahead of schedule, f) WP approach, g)

Course difference, h) Prim / Sec diverged, i) Chart datum unknown, j) Prim not WGS 84, k) Sec not

WGS 84, l) Track control stopped, m) Backup navigation, n) Low speed, o) Dangerous drift, p) Course change

The "Target / Radar Alarms" group includes various alerts essential for radar operation, such as CPA/TCPA, Lost Target, Guard Zone Target, Disk Full Save Reset, Disk Full Adjust Save, Head Marker Failure, Bearing Failure, Trigger Failure, and AIS Message.

The group of alarms "Area Alarms” contains 28

"Basic Areas” alarms and 14 “Additional Areas " alarms

The group of "Other Alarms" contains: a) Timer went off, b) End of watch, c) Time zone changed, d)

No official chart, e) Add info warning, f) Add info chart full

The "AIS Alarms" group includes various malfunctions such as Tx malfunctioning, antenna VSWR exceeding limits, and issues with Rx channels 1, 2, and 70 Additionally, it encompasses general failures, lost MKD connections, and lost external EPFS Other concerns involve the absence of sensor position, invalid SOG and COG information, lost or invalid heading, and no valid ROT information.

The "Chart Alarms" group includes several critical components: a) a Dangerous scale, b) a Not Recommended scale, c) indicators for Layers Lost, d) prompts to Look Up for a better chart, e) availability of Larger Scale charts, f) access to ENC data, g) Chart Priority and HCRF mode, h) a Safety scale that checks against larger scales, and i) the absence of an official chart.

Basic alarms play a crucial role in ensuring the safety of maritime navigation Key alarms include collision warnings, sounder depth alarms, lost target alerts, and cross track error notifications, all of which are essential for maintaining safe sea passage.

The newly introduced alarms for ECDIS systems utilizing vector charts are crucial for enhancing maritime safety These alarms include safety contour, safety depth, area alarm, and navigational danger alerts, all designed to improve navigational awareness and prevent accidents at sea.

Selecting the basic alarms may facilitate their activation, and editing the safety parameters associated with them

The effectiveness of alarms depends on the proper definition of safety parameters associated with them

Efforts to enhance navigation must consider the specific characteristics and conditions of the navigational area It is essential to selectively activate alarms, excluding system alarms, based on the type of area and navigational context Additionally, the selection of alarms should be informed by the navigator's experience and familiarity with the particular sea area, although this aspect is not explored in detail in this article.

The analysis highlights the safety parameters associated with the movement of the vessel on the surface and in the third dimension - depth and underwa- ter hazards

3.1 Navigation safety parameters associated with the movement of the vessel on the water surface

The parameters relevant to navigation safety encompass both fixed and mobile objects, focusing on aspects such as navigation accuracy, vessel positioning, and route maintenance.

The Closest Point of Approach (CPA) and Time to Closest Point of Approach (TCPA) are essential parameters for navigators to activate collision warning alarms These parameters apply to both AIS targets and radar/ARPA objects when AIS presentation is enabled When ARPA is integrated with ECDIS as a sensor, the limit values for CPA and TCPA can be independently adjusted in both systems In this setup, ARPA functions as a system sensor for ECDIS, necessitating that alarms generated by the ARPA system are also replicated in the ECDIS.

Seefeldt 9 The New Electronic Chart Product Specification S-101: An Overview

Hamburg Port Authority (HPA), former Head of the Geographic and Hydrographic Department, retired end of 2009

Work Package Leader within the integrated European Research Project EFFORTS (Effective Operation in ports); responsible for the Subproject Port ECDIS

ABSTRACT: The Hamburg Port Authority (HPA) was about 42 month, between May 2006 and October

In 2009, the Port ECDIS work package was led by HPA as part of the EFFORTS project, collaborating with SevenCs, CARIS BV, and ISSUS Maritime Logistics/TUHH The initiative aimed to develop a new Port ENC standard for navigation in ports, enhancing the capabilities of vessels, Portable Pilot Units (PPUs), and advanced marine simulators Masters and pilots rely on Electronic Chart Display and Information Systems (ECDIS) for essential navigational data, while Harbor Masters require up-to-date information for safe port operations Current ECDIS standards primarily address open sea navigation, leaving a gap for the specific needs of confined waters and port management The new Port ENC standard seeks to provide high-resolution geographic and bathymetric data necessary for managing larger vessels, increasing traffic, and optimizing berth organization and dredging activities Beyond improving electronic charts, Port ECDIS will serve various user groups, including maintenance, planning, and simulation, necessitating additional 3D data representations The Port ENC will enhance interoperability by integrating with other port data sources, playing a crucial role in the e-Navigation concept.

Fig 1: The Port ENC component

The common IHO ECDIS standard for maritime

ENC’s supports navigation in the open sea, coastal areas and in seaports (like the Port of Hamburg), the

The Inland ECDIS standard for Inland ENC’s (IENCs) is designed for navigation on inland waterways, utilizing the same accuracy and quality definitions as the maritime ECDIS standard However, it does not fully address the specific requirements of ports concerning precise navigation, maneuvering, berthing, turning, docking, maintenance, and the necessary aspects of up-to-dateness, scale, and accuracy.

Port ENC requirements exceed current maritime ECDIS and Inland ECDIS standards in terms of up-to-dateness, quality, accuracy, and the reliability of hydrographic and geographic data For effective port operations, specific vertical and horizontal accuracy is essential, which is achieved through advanced sensor technology This level of precision must also be reflected in the underlying electronic charts used in the port.

Port Authorities are responsible for providing standardized source data, such as topography and hydrographic information, in accordance with the proposed Port ENC standard As public institutions, they must ensure that this data is readily available to meet regulatory requirements and support maritime navigation.

At present, there is no standard or extensions considering the special requirements of port operations!

The Port ENC standard necessitates a specialized "Port ECDIS," which includes essential components such as gridded bathymetry and a 3D channel reference model Additionally, it is designed for compatibility with the 7Cs bathymetric ENC, enhancing navigational accuracy and efficiency in port operations.

The Port ENC standard should be an independent but complementary standard to maritime ENC and

Fig 2: ENC gradation including the Port ENC

The Port ENC standard is designed to enhance precision in port operations, aligning with the latest IHO S100 standard for maritime and inland Electronic Navigational Charts (ENCs) This standard aims to bridge the gap between maritime and inland ENCs, recognizing that seaports serve as crucial connections in the shipping industry.

Utilizing a Port ENC as a foundational element allows for the integration of various information types, enhancing the interoperability of harbor operations This includes navigation and ship maneuvering, facilitated by pilots using Portable Piloting Units (PPUs) that incorporate Port ENCs Additionally, the Port Authority can leverage the Port ENC for dredging and maintenance tasks at channels, piers, and berths Furthermore, the same Port ENC serves as a basis for traffic management and route planning within the nautical center (VTMIS).

IHO Standards lack comprehensive topographic source data for integration into Electronic Navigational Charts (ENCs), and do not specify accuracy requirements for various navigational purposes, such as port operations While the IHO S-57 Zone of Confidence (ZOC) assessment indicates the quality of bathymetric data within ENCs and Inland ENCs, it does not apply to topographic data.

Fig 3: Port ENC encoding guide proposal

The IHO S57 Standard and the latest IHO S44

Minimum Standard for hydrographic surveys should be harmonized in terms of their accuracy data

In the Port ENC, we categorize bathymetric and topographic information into two accuracy zones: Zone A and Zone B Zone A represents the highest accuracy level, meeting the IHO S44 Special Order Survey requirements, with horizontal and vertical accuracy for fixed topographical objects critical for berthing and docking better than +/- 0.1 m Zone B also adheres to the S44 Special Order Survey but maintains a topographic accuracy level of better than +/- 0.5 m, which significantly exceeds the current ECDIS standards.

An example is the official ENC of Hamburg, produced and issued by BSH (Federal Maritime and

The Hydrographic Agency of Germany has developed an Electronic Navigational Chart (ENC) that meets all relevant standards and SOLAS V carriage requirements for maritime navigation However, this ENC is limited in scale, lacks bathymetric detail, does not provide up-to-date information, and has poorly defined horizontal accuracy for topographic features like quay walls and piers A comparison between the official maritime ENC and the newly developed Port ENC indicates that the official maritime ENC is unsuitable for specialized operations within the port area.

BSH - ENC has a different purpose to meet (usage band 5 - harbor), but must be used as official ENC in the Port of Hamburg to fulfil SOLAS V carriage requirements

2 THE PORT ECDIS WORK PACKAGE –

Task 1 – Potential user requirements (Meetings, workshops, structured questionnaire)

Task 2 focuses on the technical specifications of Port ENC, emphasizing the accuracy and precision of topography and navigation aids It introduces special new Port ENC objects, detailing their features and attributes Additionally, the task highlights the importance of precise 3D depth information derived from Digital Terrain Models (DTM) technologies, along with 3D gridded bathymetry and the Channel Reference Model (CRM) as a standard for 3D reference.

Task 3 – Prototype of a Port ENC

The Port ENC dataset for the Port of Hamburg includes detailed Port ENC chart data, 3D gridded bathymetry in BAG format, bathymetric ENCs (bENC), and a 3D channel reference model (CRM).

The HPA survey vessels conducted tests that included the use of a Portable Power Unit (PPU) on a container vessel, functional assessments on a Trailer Suction Hopper Dredger (TSHD), and evaluations during the docking process of a cruise liner.

Fig 4: Port ENC + bENC (Bathymetric ENC)

Fig 5: Port ENC + 3D Gridded Bathymetry

Fig 6: Port ENC- calculated safety depth

Fig 7: 3D Gridded bathymetry data versus CRM

Fig 8: 3D gridded bathymetry data versus CRM

The figures 4 – 8 giving an overview about the results specified in Task 2 of the Port ECDIS work package

Task 5 – Defining requirements for follow-up developments and standardization (Port ENC - Roadmap)

The Port ENC serves as foundational data within the Port Information System (PORTIS), integrating various elements such as AIS, Radar, VTMIS, route planning, dredging details, and maintenance information for rivers and port basins, along with current velocity and tidal data Ongoing efforts aim to improve the prototype, expand its applications, and establish standardization.

Port ENC can also be used in Marine Simulators (ship handling, tug simulator…) et cetera

3 PORT ECDIS WORK PACKAGE RESULTS - OVERVIEW

The Port ECDIS work package resulted in a comprehensive proposal for European and international standardization, validated through functional tests in the Port of Hamburg Key outputs included a paper on the current data quality standards for ENC data, comparing S57 and S44 standards, as well as several Port ENC specification documents such as the "Port ENC Feature Catalogue," "Port ENC Encoding Guide," and "Port ENC Product Specification." Additionally, a prototype software and dataset for the Port of Hamburg, including a Port ENC viewer, was developed.

Powell

Applications and Benefits for the Development of Cartographic 3D Visualization Systems

Visualization Systems in support of Maritime Safety

Goralski, C Ray & C Gold 11 Assumptions to the Selective System of Navigational-maneuvering Information Presentation

Institut de Recherche de L’Ecole navale

Faculty of Advanced Technology, University of Glamorgan, UK

Maritime shipping is crucial to the global economy, but increasing traffic levels heighten the risk of marine accidents, threatening the safety of crews, the environment, and shipping profitability This emphasizes the urgent need for advanced maritime navigation systems aimed at enhancing maritime safety Efficient electronic charting and radar display systems are essential for improving situational awareness among ship navigators, Vessel Traffic Services (VTS) operators, and marine pilots The use of cartographic 3-dimensional visualization (3D charting) significantly aids in quickly grasping navigational situations, reducing mental overload, and minimizing fatigue, thereby supporting better decision-making for sailors and maritime authorities Ultimately, these advancements help decrease human error, the leading cause of marine accidents, and this paper explores the latest developments in 3D visualizations for marine navigation, VTS, and pilotage.

Human errors can also come from control centre

Vessel Traffic Services (VTS) play a crucial role in assisting individuals onshore who may struggle to assess and anticipate situations due to heavy maritime traffic While marine pilots possess extensive navigation skills and local knowledge, they are not infallible and can make mistakes An example of this is highlighted in the investigation of the Vallermosa grounding incident, which underscores the importance of VTS in enhancing maritime safety and preventing accidents.

A study by Branch (2009) identifies key factors contributing to accidents involving pilot-led vessels, including inadequate support from ship crews, mental overload, a lack of understanding and control over evolving situations, diminished situational awareness, and insufficient coordination and support from Vessel Traffic Service (VTS) operators.

The latest technological breakthroughs including radar, electronic charting (Electronic Chart Display

Information Systems, ECDIS), traffic control and management (VTS) and automatic identification and communication (Automatic Identification System,

The introduction of AIS has greatly enhanced maritime navigation safety by improving navigational awareness and providing vital collision-avoidance information to navigators Despite these advancements, marine accidents continue to occur frequently, often resulting from factors such as fatigue, mental overload, and a limited understanding of the navigational environment.

Enhancing chart display systems through visually efficient and user-friendly 3D cartographic visualization can significantly improve navigation for pilots, navigators, and VTS operators.

Three-dimensional charts are proven to dramatically reduce the number of human mistakes and improve the accuracy and time efficiency of navigational operations, compared to traditional 2D charts (Porathe

Incorporating Electronic Chart Display Information Systems (ECDIS) in maritime safety management can significantly minimize human error and reduce accidents These systems are applicable at various stages, including on-board navigation, vessel traffic monitoring (VTS), and pilotage Additionally, they play a crucial role in training and offer valuable insights during accident investigations.

Maps, one of the oldest forms of graphical communication, serve as highly effective tools for conveying spatial and geographical information Throughout history, various types of maps have emerged, each reflecting diverse cultural backgrounds and applications in our daily lives In recent years, the transition from paper to digital formats has significantly increased the popularity of maps, making them more accessible and widely used than ever before.

Electronic charts provide significant advantages over paper charts in navigation, enabling real-time analysis of vessel positions and chart data to prevent groundings They seamlessly integrate with bridge equipment and consolidate information from various sensors, including GPS, radar, and AIS Additionally, electronic charts automate routine navigational tasks, such as course plotting and route parameter calculations, enhancing overall navigational efficiency.

This integration and automation helps in reduction of navigators’ workload, and offers more accurate understanding of the navigational situations

Electronic charting is strongly endorsed by the International Maritime Organization (IMO) and the International Hydrographic Organization (IHO), along with member state regulators, who established a standard for the Electronic Chart Display Information System (ECDIS) This initiative aims to replace traditional maritime maps on commercial ships with automated electronic charts An ECDIS system utilizes official nautical chart data from the International Hydrographic Bureau, enhancing navigation safety and efficiency at sea.

The vector IMO/IHO Electronic Navigational Chart (ENC) format, produced by national hydrographic offices, is a type-approved real-time 2D display that meets performance and display standards for a vessel's current GPS position This system includes a user interface for essential navigational tasks and can optionally integrate data from AIS, radar, and other bridge instruments.

Figure 1 ENC chart no GB50162B – the Port of Milford Ha- ven – as viewed in an ECDIS, with additionally marked location of the Port Control (VTS operations centre)

Starting from July 2012, the mandatory carriage of type-approved ECDIS will be implemented on all merchant and passenger ships, with a transitional schedule for different ship categories New passenger ships over 500 gross tons and new tankers above 3000 gross tons must comply by this date, while existing dry cargo ships over 10,000 gross tons will need to retrofit by July 2018.

VTS centers and pilots often utilize unofficial chart display systems that are based on official Electronic Navigational Charts (ENC), providing enhanced functionality for analyzing situations and monitoring port operations.

Leisure boating enthusiasts have access to a wide range of chart plotters that are not bound by regulations, and these devices are increasingly popular due to their enhanced functionality.

The main purpose of a charting system, or an EC-

The Display and Information System (DIS) enhances navigation by overlaying the ship's position, obtained from satellite navigation transponders, onto a digital chart, effectively presenting relevant navigational information.

Digital charts offer the significant advantage of seamlessly integrating additional information from various systems and onboard sensors This includes essential meteorological data from weather stations or forecasts, digital compass readings, and crucial information about surrounding obstacles and traffic, which aids in danger avoidance Sources of this data include radar for detecting drying features and other vessels, sonar for bathymetry, and the Automatic Identification System (AIS) AIS represents a major technological advancement, enabling reliable detection and identification of ships within a range of up to 35 nautical miles An AIS transponder typically combines a transceiver system for enhanced maritime safety.

Gralak 12 Security Modeling Technique: Visualizing Information of Security Plans

Institute of Marine Traffic Engineering, Maritime University of Szczecin, Poland

In the context of advancing transportation technologies, a three-dimensional visualization system has been developed to simulate real navigation scenarios for ships in confined areas This system is an integral component of eNavigation, designed to aid navigators on the ship's bridge, especially during berthing maneuvers The article outlines the technical specifications of the system, highlighting its purpose and innovative features, such as multi-territorial virtualization and the capability to display the actual position of individual vessels.

GPS/DGPS, very cumbersome in mooring maneuvers, vector coastline often do not coincide with the actual shape of the berths, simplified the waterline of the vessel (Fig 1);

Figure 1 ECDIS – costal line deformation (Own work)

Radar / ARPA systems – presentation of vessel’s location and anti-collision system mainly used in the open sea voyage, not very accurate and inefficient inside the ports (Fig 2);

Figure 2 Radar/ARPA echoes distortion (Own work)

DP systems, or Dynamic Positioning systems, are advanced and costly technologies used primarily on specialized vessels and ferries to accurately determine and maintain their location However, implementing these systems on standard merchant fleet units is often prohibitively expensive and inefficient.

Dedicated positioning and presenting of ship’s location systems - systems created against order, dedicated for a specific restricted areas or port infrastructure (LNG, Ferries, Narrow Channels)

Highly accurate positioning systems, including Real Time Kinematic (RTK), ladars, and ultrasound, enable safe navigation for ships These systems primarily provide two-dimensional information presentations with simplified ship models.

Figure 3 Dynamic Positioning Interface (Kongsberg AS

Figure 4 Dedicated LNG positioning system (Gucma, S &

Invariably, for centuries the simplest and most efficient way to assess the vessel's location in space in the restricted areas, in ports is a visual observation

Modern navigation bridge systems cannot fully replace the human factor; therefore, it is essential to equip navigators with comprehensive navigation and maneuvering information presented in an ergonomic format.

The utility of systems that indicate a vessel's position relative to berths during the final phase of passage and berthing maneuvers is significantly constrained due to both systematic and unsystematic errors.

The only reliable source of information for decision-making is a visual observation However, it has two basic limitations:

1 is strongly dependent on the currently prevailing hydro-meteorological conditions, particular on the degree of visibility,

2 the navigator has the ability to simultaneously observe only one side of the ship

Navigating long ships with a stern superstructure presents challenges, as the bridge navigator cannot accurately gauge the distance between the bow and nearby obstacles at waterline height Similarly, a bow superstructure limits visibility of the stern's position To ensure safe approaches and berthing maneuvers, it is essential to provide navigators with external positional information, typically through a crew member using a radio communication device or a CCTV camera installed on the quay or vessel However, both methods face significant limitations in heavy fog conditions.

We developed a selective system for presenting navigational and maneuvering information using mathematical and graphical models tailored for specific vessels and their environments This innovative system enables a comprehensive, multi-level evaluation of a vessel's position in relation to obstacles, ensuring effective navigation under any weather conditions.

The primary objective of the system is to accurately replicate real navigational scenarios using mathematical and graphical models of both the vessel and its surrounding area These models are integrated into a virtual environment, where they utilize standardized data from positioning systems to achieve spatial placement in three degrees of freedom, with plans to expand to six degrees of freedom in the future.

The mathematical graphic ship model is constructed in a three-dimensional environment, utilizing technical documentation from the unit owner This virtual hull accurately replicates the real vessel's scale, location, and shape, encompassing both above and below the waterline.

Figure 5 Graphical ship’s model (Own work)

The level of detail in the model is influenced by the complexity of the original hull's design Additionally, it is possible to create a virtual representation of both the fixed elements attached to the hull and the moving components.

A three-dimensional mathematical model of areas is developed using technical spatial plans and digital maps In cases where accurate plans are lacking, the virtual model of the basin can be created through geodetic measurements of wharves, utilizing technologies such as RTK.

Figure 6 Graphical area’s model (Own work)

In addition to the model of the area coastline it is also necessary to make a virtualization of: buoys and navigation marks hydrotechnical architecture, water surface (simplified model)

Thus prepared, the model is positioned in the WGS84 datum of the behavior of the real values of coordinates Lat / Lon or UTM

The system consists of two blocks:

1 collecting and recording of input data into system memory

The data collection and recording block is a standalone algorithm that enables the integration of variables from diverse independent sources into the system, eliminating the need for modifications to the second block's code This flexibility allows for the seamless connection of various positioning systems and continuous hydro-meteorological data.

Manual defining of the fixed input is also available

Figure 7 Collecting and recording block (Own work)

The reading and data processing block is crucial for dividing and assigning relevant variables to the mathematical and graphical models of the vessel and its surrounding area.

Figure 8 Reading and data processing block (Own work)

In the first version of the software there are available:

The ship's model data includes essential parameters such as the date and time, local coordinates from the bridge's viewpoint, and the antenna's location for the positioning system Additional reference points for the ship's hull can be defined, along with critical metrics like heading, global antenna position, draught, and trim/pitch values, which require an additional gyro for automatic readings Furthermore, the data encompasses roll values, longitudinal and transverse speeds, as well as the strength and direction of current and wind, all crucial for accurate navigation and performance assessment.

The basin model requires essential data inputs, including the current water level, a simplified sea state, and rainfall intensity, which is automatically measured using additional sensors Additionally, fog levels can also be monitored automatically, contingent upon the installation of supplementary sensors.

Models with the actual data associated, create a virtual interface that reflects the actual navigation- maneuvering situation

The concept of an interface for the involves the implementation of the following features (Fig 9):

1 The main screen - a view from the bridge at the centerline of the ship;

2 The navigation bar - the presentation of weather and maneuvering information, with the option of transfer to any location on the screen;

4 New camera button - a function that allows sim- ultaneous viewing up to five places in the vicinity of the ship,

5 Preview of added cameras – by clicking on the thumbnails for the camera larger screen is obtained

Figure 9 Proposal of system interface (Own work)

Ley & E Dalinger

D Ilcev 14 On a Data Fusion Model of the Navigation and Communication Systems of a Ship

Durban University of Technology (DUT), Durban, South Africa

The implementation of Maritime Satellite Communications, Navigation and Surveillance (CNS) systems, utilizing GPS or GLONASS, is crucial for enhancing safety and emergency systems, as well as security and control of vessels, logistics, and freight at sea and on inland waters With the world's merchant fleet expanding, and top 20 ship registers having over 40,000 units under their national flags, the need for improved management and operation of vessels has become more pressing The International Maritime Organization (IMO) and flag states play a vital role in developing International Ship and Port Security (ISPS), which can be effectively implemented through an Approaching and Port Control System (APCS) utilizing satellite CNS for tracking and monitoring vehicle circulation in seaport areas.

Navigation Overlay System (EGNOS) and Japanese

MTSAT Satellite-based Augmentation System

(MSAS), and there are able to provide CNS data from mobiles to the TCC via Geostationary Earth

These three RSAS are integration segments of the

GSAS network and parts of the interoperable GNSS-

1 architecture of GPS and GLONASS and new

GNSS-2 of the European Galileo and Chinese Com- pass, including Inmarsat CNSO (Civil Navigation

Satellite Overlay) and new projects of RSAS infrastructures The additional four RSAS of GNSS-1 networks in development phase are the Russian Sys- tem of Differential Correction and Monitoring

(SDCM), the Chinese Satellite Navigation Augmen- tation System (SNAS), Indian GPS/GLONASS and

GEOS Augmented Navigation (GAGAN) and Afri- can Satellite Augmentation System (ASAS) Only remain something to be done in South America and

Australia for establishment of the GSAS infrastructure globally, illustrated in Figure 1

Courtesy of Book: “Global Aeronautical CNS” by Ilcev [01]

RSAS solutions utilize GNSS-1 signals for augmentation, evolving into the GSAS network, which offers overlay functions and supplementary services The upcoming ASAS Space Segment will include existing GEO satellites like Inmarsat-4 and Artemis or may deploy its own satellite constellation to transmit overlay signals that closely resemble those of GNSS-1.

GPS and GLONASS and provide CNS service The

IS Marine Radio, a South African firm, will oversee the design and development of the ASAS network, collaborating with all regional governments to ensure successful implementation.

RSAS infrastructures are globally available to improve the performance of standalone GPS and GLONASS systems for maritime, land, and aeronautical transport applications User devices can utilize internal sensors to enhance robustness against jamming and assist navigation in urban canyons or mountainous areas where satellite signals may be obstructed Additionally, specialized transport solutions, particularly in maritime and aeronautical sectors, demand higher accuracy and reliability in CNS than what current military GPS and GLONASS infrastructures offer.

To enhance positioning accuracy, correlated errors between multiple GPS and/or GLONASS receivers measuring the same satellites can be eliminated This process utilizes a Reference Receiver (RR) with a precisely known geographical location By calculating the difference between the RR's surveyed position and its electronically derived position at a specific time, the resulting discrepancies indicate measurement errors, referred to as differential corrections This correction information can be transmitted via a GEO data link to user equipment, allowing GPS or GLONASS augmented receivers to effectively remove these errors from their received data.

In non-real-time GNSS solutions, differential corrections are stored with the user's positional data and applied after the data collection period, making this method ideal for surveying applications.

The local area differential mode, akin to the US DGPS for maritime applications, is utilized by mobile users when connected to the RR or Ground Monitoring Station (GMS) As the distance between users and the GMS increases, ranging errors can become decorrelated To address this issue, a network of GMS reference sites can be established across vast geographic areas, such as regions or continents, to broadcast Differential Corrections (DC) via GEO satellites This approach aims to create a comprehensive ASAS network that spans the entire African continent and the Middle East region.

GMS sites connected through Terrestrial Telecommunication Networks (TTN) relay data to Ground Control Stations (GCS) for data correction (DC) and satellite signal integrity checks The GCS then transmits corrections and integrity data to a Ground Earth Station (GES) for uplink to the GEO satellite This differential technique is known as the wide area differential system, implemented by the GNSS system called Wide Augmentation Area (WAA), alongside another system known as Local Augmentation Area.

(LAA) is an implementation of a local area differential [05]

The LAA solution is designed for seamless integration at seaports and airports, enhancing their operational capabilities Meanwhile, the WAA serves as a comprehensive wide-area differential system, supporting a range of CNS applications across maritime, land, and aeronautical sectors, including Inmarsat services.

CNSO and the newly developed Satellite Augmenta- tion WAAS in the USA, the European EGNOS and

Courtesy of Book: “Understanding GPS - Principles and Ap- plications” by E.D Kaplan [03]

These three operational systems are part of the worldwide GSAS network and integration segments of the future interoperable GNSS-1 architecture of

GPS and GLONASS and GNSS-2 of Galileo and

Compass, which includes CNSO as part of its GNSS offerings, provides this service through the Inmarsat-3/4 and Artemis spacecraft This paper introduces the term GSAS, which serves as a more accurate nomenclature for the discussed services.

Satellite-based Augmentation System (SBAS) of

ICAO, which has to be adopted as the more common designation in the field of CNS [06]

As discussed earlier, the current three RSAS networks in development phase are the Russian SDCM,

Chinese SNAS and Indian GAGAN, while African

In early 2011, the Continent and Middle East initiated the development of the ASAS project, marking a significant step forward This foundational effort will pave the way for the upcoming RSAS projects in Australia and South America, which are set to enhance regional growth and collaboration.

Augmented CNS system worldwide, known as an

Three operational RSAS together with Inmarsat

CNSO systems are designed for interoperability and compatibility, consisting of a network of GPS or GLONASS observation stations along with proprietary or leased GEO communication satellites Specifically, the Inmarsat CNSO system provides leased GNSS payloads to the European EGNOS system, which enhances positioning accuracy to within approximately 5 meters and is currently operational.

2009 In fact, it also constitutes the first steps towards forthcoming Galileo, the future European system for civilian global navigation by satellite The

EGNOS system uses leased Inmarsat AOR-E and

IOR satellites and ESA ARTEMIS satellite Thus, the US-based WAAS is using Inmarsat satellites and

The Japanese MSAS utilizes its multipurpose MTSAT spacecraft, which has been operational since 2007 and 2008 The accuracy of the global positioning system associated with this overlay depends on various technical factors, including the ground network architecture The expected positioning accuracy for the US Federal Aviation Administration (FAA) WAAS is approximately 7.6 meters (2 drms, 95%) in the horizontal plane and 7.6 meters (95%) in the vertical plane.

The RSAS network is designed as the primary satellite communication and navigation system for maritime operations, facilitating ocean crossings, navigation in open and coastal waters, and access to ports and anchorages Additionally, it supports land transportation solutions for roads and railways, as well as aviation routes over continents and oceans, enabling efficient management of airport approaches and surface movements of aircraft and vehicles.

It was intended to provide the following services:

The GNSS Integrity Channel (GIC) provides real-time transmission of integrity and health information from each GPS or GLONASS satellite, ensuring that users avoid relying on faulty satellites for navigation.

K Park & Y.-K Kim 15 Automation of Message Interchange Process in Maritime Transport

Division of Maritime Transportation System Mokpo National Maritime University, Republic of Korea

Shipmates must effectively interpret various forms of information, including images, numerical values, text, and audio from radar, AIS, NAVTEX, and VHF, to ensure safe navigation However, the complexity of acquiring and utilizing this data for decision-making during watchkeeping poses significant challenges Therefore, there is a critical need for a system that can consolidate and present multimedia marine information in a voice format for easier understanding by crew members This study proposes a data fusion model aimed at enhancing navigation and communication systems for improved maritime safety.

3.1 Data field of navigational equipments

To use the information provided by navigation equipments, the information provided by the equipment was analyzed and data field for the equipment were prepared

GPS, ARPA and AIS information should provide which is specified in SOLAS resolutions

NAVTEX delivers information in a text format using English alphabet characters, ensuring that natural language processing is effectively applied to achieve accurate data representation.

NAVTEX delivers essential navigation warnings, weather alerts, and urgent safety notifications, including information on new navigation obstructions, changes to navigational aids, construction activities, training exercises, and severe weather events Each notice includes critical details such as the name of the warning, its validity period, and the specific location or area affected.

VHF communication equipment operates on specific frequencies and utilizes human language for direct communication, allowing for limitless information exchange A key advantage of VHF is its ability to convey the intentions of other vessels, enhancing maritime safety and coordination.

Using these, data fields were prepared

To use information that can be provided by navigational equipments, it was assumed that speech recognition and natural language processing had been completed

The Knowledge Representation Model utilizing navigation instruments was developed to illustrate the relationships between subject-related data through a semantic network Each piece of equipment conveys information in straightforward sentences, while the representation of knowledge by subjects is formed through the insights gained from these navigation tools.

3.2.1 Knowledge Representation Model of GPS

All information provided by GPS is included

Figure 2 is Knowledge Representation Model of

GPS and it expressed information which is provided by this model in a simple sentence

“Ownship’s Position’s GPS position Is latitude

Figure 2 Knowledge Representation Model of GPS

3.2.2 Knowledge Representation Model of ARPA

ARPA provides essential location information, including D1: Bearing and D2: Range, which are integrated as positional data This information is then amalgamated with data from other navigation instruments to enhance overall accuracy and reliability.

Figure 3 is Knowledge Representation Model of ARPA, and it expressed information which is provided by this model in a simple sentence

“Ship 1’s Position is Bearing 312 degree.”

Figure 3 Knowledge Representation Model of ARPA

3.2.3 Knowledge Representation Model of AIS

All information which is provided by AIS can be expressed but only D14: GPS position as location information was connected to ship as subject through the vertices as position

Figure 4 is Knowledge Representation Model of AIS, and it expressed information which is provided by this model in a simple sentence

Figure 3 Knowledge Representation Model of AIS

3.2.4 Knowledge Representation Model of NAVTEX

It was designed using data field of NAVTEX

NAVTEX, and it expressed information which is provided by this model in a simple sentence

“Object 1’s Name is Dangerous wreck.”

“Object 1’s Position is latitude 34 12.5 N and longitude 126 22.5 E.”

Figure 5 Knowledge Representation Model of NAVTEX

3.2.5 Knowledge Representation Model of VHF

It was designed using data field of VHF

VHF, and it expressed information which is provided by this model in a simple sentence

Figure 6 Knowledge Representation Model of VHF

A data fusion process is necessary for fusing a knowledge representation model into a data fusion model

To determine if the data from two knowledge representation models pertains to the same objects, it is essential that the data with equivalent meanings is comparable A judgment can be made regarding the similarity of the data, and if this similarity falls within a specified range, it can be concluded that both models provide information about the same objects.

Figure 7 shows a proposed data fusion algorism

3.4.1 Data fusion model in the case of a ship as target

Information about ships can be acquired through ARPA, AIS, and VHF systems This data is effectively represented by integrating the knowledge models of ARPA, AIS, and VHF technologies.

Figure 8 is data fusion model in the case of a ship as target

Figure 8 Data fusion model in the case of a ship as target

3.4.2 Data fusion model in the case of a object as target

Information regarding subjects other than ships can be acquired through systems like ARPA and NAVTEX This data is effectively represented by integrating the knowledge representation models of both ARPA and NAVTEX.

Figure 9 is Data fusion model in the case of a object as target

Figure 9 Data fusion model in the case of the subject as except ship

4 APPLICATION OF DATA FUSION MODEL

4.1 Description of navigation situation using data fusion model by subject

The navigation scenario, along with information about other vessels and marine obstacles, can be effectively represented using a Data Fusion Model, highlighting the subject's relevance in the context of the given navigation situation.

The navigation situation of Figure 10 is a dangerous one in which two ships are encountering while they pass through a narrow channel

Figure 10 Navigational Situation “Dangerous Stage”

4.2 Navigation situation expression of information that can be obtained from Data Fusion Model

Figure 11 shows a data fusion model for the information acquirable in a dangerous situation of scenario

The data fusion model in Figure 11 can provide all the information provided by navigation equipment in a navigation of scenario in a simple sentence

This expresses the meaning of information on

Ship1, Ship2 and Object1 provided by a given data fusion model in a simple sentence

“Ship 1’s Position Is D1:Bearing Is 304.”

“Ship 1’s Position Is D2:Range Is 2.12 miles.”

“Ship 1’s Position Is D14:GPS position Is Lati- tude 34 19.4 N and longitude 126 05.85 E

“Ship 2’s D6:Ture speed Is 10.0 kts.”

“Ship 2’s D18:Rate of turn Is 0.0/min.”

“Object 1’s Position Is D1:Bearing Is 332.”

“Object 1’s Position Is D2:Range Is 1.7 miles.”

“Object 1’s Position Is D14:GPS position Is Lati- tude 34 19.75 N and longitude 126 07.0 E

“Object 1’s D9:Name Is Dangerous wreck.”

Figure 11 Navigation situation expression using the Data Fu- sion Model for each object

4.3 Navigation situation expression using the Data fusion model

Figures 12, 13 and 14 express the information ob- tainable through induction by a mate in a navigation situation of scenario using a data fusion model in Figure 11

The data fusion model reveals that the CPA (Closest Point of Approach) for Ship1, Ship2, and Object1 is within one mile and occurs in less than seven minutes, indicating a significant danger.

The meaning except for the meaning created newly after induction can be expressed linguistically

“Ship1's CPA Is 0.15mile, TCPA Is 5:2, Ship2`s CPA Is 0.0mile, TCPA Is 4:17, Object1`s CPA Is 0.6mile, TCPA Is 6:24.”

Figure 13 expresses the information of a sentence induced by combining the meaning of an object acquired from multiple navigation equipment “Object1 has Bearing 332°, Range 1.7mile, CPA 0.6mile, and

TCPA 6:24, and its name is Dangerous wreck”using a data fusion model

All the meanings of a sentence can be expressed

“Object1 `s Bearing Is 332°, Range Is 1.7mile,

CPA Is 0.6mile, TCPAIs 6:24, Name Is Dangerous wreck.”

Figure 14 expresses the information of a sentence inducing a situation and presenting a solution by combining the meanings of an object acquired from multiple navigation equipment “Ship 1 has CPA

0.15mile and TCPA 5min 2sec, but it doesn’t veer and respond to communication, so do DSC(Digital

Selective Calling) for IMO No 440100002”using a data fusion model

The induced meaning cannot be expressed, but the information can be expressed

“Ship1`s CPA Is 0.15mile, TCPA Is 5min 2sec,

Rate of turn Is 0.0°/min, Intention is nothing, DSC Is

Ship1`s CPA Is 0.15mile, TCPA Is 5min 2sec,

But, Rate of turn Is 0.0°/min, Intention is nothing ଃ

This study introduces a data fusion model that utilizes a semantic network to analyze and interpret information from various navigation equipment, including GPS, ARPA, AIS, NAVTEX, and VHF receivers By integrating data from these sources, the model enhances the understanding of navigation situations and clarifies the types of information that can be obtained and inferred during specific navigational scenarios.

The test of the proposed model in some real navigation situations will be done to verify its validity in future

In the study "Ship Collision Avoidance Support System Using Fuzzy-CBR" by John Leslie Benedictos, published in the Journal of the Korean Institute of Intelligent Systems, Gyei-Kark Park explores innovative methods for enhancing maritime safety The research, featured in Volume 16, Issue 5, pages 635-641, focuses on the application of fuzzy case-based reasoning (CBR) to develop an effective collision avoidance system for ships, highlighting its potential to significantly reduce maritime accidents.

The article titled "Conceptual Model for Fuzzy-CBR Support System for Collision Avoidance at Sea Using Ontology," authored by Woong-Gyu Kim, John Leslie RM Benedic- tos, and published in the Journal of the Korean Institute of Intelligent Systems, discusses a conceptual framework utilizing fuzzy case-based reasoning (CBR) to enhance maritime collision avoidance This research, featured in volume 17, issue 3, pages 390-396 of the 2007 journal, emphasizes the integration of ontology to improve decision-making processes in marine environments, ultimately contributing to safer navigation at sea.

Tae-ho Hong, Ki-Yeol Seo, and Gyei-Kark Park presented their research on developing an Integrated Navigation Guiding System utilizing Electronic Navigational Charts (ENC) This study was published in the Proceedings of the Korean Institute of Intelligent System's Spring Conference, Volume 15, Issue 1, spanning pages 394 to 399 in 2005 Their work contributes to advancements in navigation technology, focusing on the integration of ENCs for improved guidance systems.

Pietrzykowski, G Hoowiski, J Magaj & J Chomski 16 An Invariance of the Performance of Noise-Resistance of Spread Spetrum Signals

Maritime University of Szczecin, Szczecin, Poland

This paper explores the automation of data message interchange in maritime transport, proposing a comprehensive communication system It addresses challenges in automatic communication within marine navigation and outlines the principles and structure of communication utilizing a maritime transport communication ontology with XML Schema The study highlights automated negotiations among communication entities in maritime transport and emphasizes the significance of efficient and user-friendly interfaces in contemporary systems.

The maritime communication system interface must facilitate the visualization of both source and destination entities involved in the communication process This feature is essential for navigators to clearly identify all participants, enhancing operational awareness through visual verification of communication participants.

Figure 1 Scheme of proposed communication between two objects (e.g ships) Note: a gray marked elements show automated data processing

The proposed system concept serves as a foundation for an automated negotiation system in maritime transport, functioning as an expert system to enhance navigation efficiency This automated or semi-automated negotiation support system must incorporate essential functionalities, including information sharing among entities such as ship positions, speeds, and courses, as well as facilitating auto-negotiation through the use of agents.

In Beam 1997 it is acknowledged, with a support of several examples, that building an automated negotiation system is a challenging and difficult task

The study emphasizes the importance of ontology and a clear negotiation strategy in maritime transport Ontology involves categorizing objects to ensure they hold semantic significance for software agents In contrast to traditional trading systems where negotiation strategies remain confidential, a transparent approach is essential in navigational environments.

Automated communication is essential for realizing the aforementioned functionalities The subsequent sections will outline an ontology and its implementation in XML Schema, which are necessary for facilitating this automated communication.

3 THE ONTOLOGICAL STRUCTURE OF MESSAGES IN MARITIME TRANSPORT

Ontology is crucial for enhancing information exchange in maritime transport by offering a unified understanding of the domain It facilitates effective communication and knowledge sharing within the industry The challenges related to ontology in maritime transport have been discussed in various studies, including those by Malyankar et al (1999), Mingyang P et al (2003), and Kopacz et al.

Radiotelephone VHF communication is a key method for exchanging messages between vessels and coast stations Each communication consists of a single message, typically formed by simple sentences conveying essential navigational information For instance, in situations involving ship encounters, these messages play a crucial role in ensuring safe navigation.

Alpha: ‘Our CPA is close to 0’, Alpha: ‘Is it possible that we pass starboard to starboard?’

Navigational information is conveyed through attributes, which are essential components of communication at sea For instance, a complex sentence may include multiple attributes, such as in the example: “I intend to alter my course to starboard soon and cross ahead of you at a safe distance.” This statement effectively communicates the navigator's intention to change course and specifies the closest point of approach after the maneuver, ensuring clarity and safety in maritime navigation.

In a single sentence, multiple attributes can be included if they share the same simple sentence structure when stated individually This means that we cannot convey one piece of information while simultaneously inquiring about another within the same sentence.

Figure 3 Sentence attributes divided into sentence forms

Considering the forms of sentences, we should note that they significantly affect the meaning of formulated messages A single message can be expressed as an interrogative and positive sentence

According to established guidelines and recommendations for maritime communication (IMO 2002, IMO 2005), information is defined as a collection of attributes applicable to various sentence types, including questions and answers.

Figure 3 shows that all information about intentions, permissions, information, warnings and re- quests can be expressed in the form of statements

The collection of attributes concerning intentions, permissions, and information can be expressed through questions, such as inquiries about permission for a specific maneuver, or through answers, which indicate the granting of that permission.

The ontological structure of a message (Fig 4) in the proposed automatic communication results from the structure of verbal communication and technical conditions:

Header – supplemental data placed at the begin- ning of a block of data being transmitted, includes:

Sender – object sending a message (ship, coast station),

The receiver refers to the objects, such as ships or coast stations, that receive messages from the sender within a defined area Key elements of the message include the time it was sent, validity duration, communication ID, and details regarding message repetition.

Body – information content of the message

Messages can be transmitted from a sender to a specific destination using unicast addressing, to a group of interested recipients through multicast, or to locations identified by geographical coordinates via geocasting.

Figure 4 Structure of a message for automatic communication

In the last case the location is pointed by rectangular or circular area described with geographical coordinates, where elevation is an optional parameter

The body of the message consists of three groups of data related to all possible types of sentences: questions, answers and tells

4 USE OF XML SCHEMA TO DESCRIBE

The development of ontology and its technical description of message syntax follows a cyclic process, which involves several key steps in each iteration: updating requirements and analysis, designing the ontology, implementing and testing the technical description of messages, and maintaining the system This iterative cycle ultimately leads to an enhanced version of both the ontology and the document description.

Defining the ontology for maritime transport communication is a crucial step in ensuring effective design Once established, it is essential to detail the syntax and structural constraints, enabling the generation and validation of XML messages within a telecommunications system.

XML Schema or DTDs can be used for that purpose

D Ilcev 18 Shipborne Satellite Antenna Mount and Tracking Systems

This paper highlights the significant impact of surface reflections and local environmental factors on Maritime Satellite Communications (MSC), which can adversely affect satellite link performance while occasionally providing signal enhancements Local environmental influences, such as shadowing and blockage from nearby objects and vegetation, are critical considerations for Ship Earth Stations (SES) and mobile terminals The study explores both the advantages and disadvantages of these effects, examining surface reflections from nearby SES terminals and distant structures like mountains and industrial facilities It concludes with specific challenges faced in mobile environments, including interference from adjacent satellite systems, local environmental influences, noise contributions from nearby ships, and blockages caused by ship superstructures and antenna motion Proposed solutions aim to optimize satellite communication capacity for mobile applications, emphasizing the importance of understanding how circularly polarized waves can become elliptically polarized upon reflection.

2 Specular Reflection from a Smooth Spherical

On Earth, the angle at which a signal grazes the surface matches the angle of reflection The amplitude of the reflected signal is determined by multiplying the amplitude of the incident signal by the absolute value of the reflection coefficient.

When rays are secularly reflected from a spherical surface, the reflection coefficient experiences an effective reduction This phenomenon is attributed to a geometrical effect caused by the divergence of the rays.

4 Reflection from Rough Surface – In many practical cases, the surface of the Earth is not smooth

When a surface is rough, the reflected signal consists of two distinct components: the specular component, which remains coherent with the incident signal, and the diffuse component, which varies in amplitude and phase.

5 Total Reflected Field – The total field above a reflecting surface is a result of the direct field, the coherent specular component and the random diffuse component

6 Reflection Multipath – Owing to the existence of surface reflection phenomena signals may arrive at a receiver from multiple apparent sources

The combination of direct line-of-sight signals with specular and diffusely reflected waves leads to signal fading at the receiver This multipath fading, along with varying levels of shadowing and blockage of the line-of-sight components, can result in significant and rapid reductions in received signal power.

MES and is really the dominant impairment in the

3 FADING IN MMSC AND AMSC SYSTEMS

DUE TO SEA SURFACE REFLECTION

Multipath fading caused by sea reflection occurs due to the interference between direct and reflected radio waves These reflected waves consist of coherent and incoherent components, specifically specular and diffuse reflections, which fluctuate over time with the movement of sea waves Under calm sea conditions and low elevation angles, the coherent component is more prominent, while the incoherent component gains significance during rough sea conditions By understanding the intensity of the coherent component and the variance of the incoherent component, it is possible to determine the cumulative time distribution of signal intensity through statistical analysis.

A prediction model for multipath fading due to sea reflection was initially created for MMSC systems operating at approximately 1.5 GHz While the sea reflection mechanism is similar for both MMSC and AMSC systems, the fading characteristics are expected to vary due to the significantly higher speed and altitude of aircraft compared to ships Consequently, the impacts of refraction and scattering from the sea surface are notably pronounced in both MMSC and AMSC, especially when wide beam width antennas are employed.

The significant wave height (H) is the primary parameter used to characterize sea conditions, representing the average peak-to-trough heights of the highest one-third of waves This measurement is empirically linked to the root mean square height (ho).

At a frequency of 1.5 GHz, smaller-scale waves can be disregarded, with the root mean square (r.m.s.) value of sea surface slopes ranging from 0.04 to 0.07 for wave heights below 4 meters.

As the satellite elevation angle decreases, the propagation path lengthens, leading to a reduction in signal power at the receiver Initially, the noise level remains stable; however, when the elevation angle drops below a critical threshold, sea-reflected signals begin to interfere with the received signal, impacting the Carrier-to-Noise (C/N) ratio To accurately account for the effects of multipath interference from these sea-reflected signals, the reception quality should be expressed as C/N plus M, where M represents the disturbance caused by the interfering sea-reflected signals These sea-reflected signals can be categorized into two distinct types based on their structural differences.

Radio signals exhibit rapid fluctuations in amplitude and phase, potentially influenced by frequency shifts caused by the movement of small portions of the specular cross-section in relation to the signal source, which may include noise or diffused components.

2 Radiowaves with relatively slowly changing phase close to the phase of the basic signal and with an amplitude correlating with that of the basic signal (specular component)

In the overall specular cross-section, the angle of arrival of reflected radio signals relative to the horizontal plane can be considered constant, which can be expressed mathematically.

The angle of radio signal arrival, denoted as 90°, and the reflection angle are crucial in understanding signal behavior For L-band signals, the sea reflection factor ranges between 0.8 and 0.9, indicating that the amplitude of the specular reflected signal is nearly equal to that of the direct signal Measurements reveal that the noise component is influenced solely by the elevation angle and wave height; a decrease in elevation angle coupled with an increase in wave height leads to a rise in total noise amplitude Specifically, at elevation angles below 5°, the amplitude reaches a peak and becomes unaffected by wave height, with further increases in wave height resulting in more frequent noise variations This variation in noise component correlates with a deviation in Carrier-to-Noise (C.N) measured within a 1 kHz bandwidth, ranging from 4.5 to 5 dB.

Figure 1 Geometry of Sea Reflection of Satellite Radio Signals

Courtesy of Book: “Global Mobile Satellite Communications” by D.S Ilcev

The presence of the specular component at the Rx input, alongside the direct signal, leads to fading in the direct signal, influenced by the slight phase differences and the gradual variations in the parameters of the reflected signals This relationship can be quantified by the ratio of the direct signal to the specular reflected signal.

C/M = (C + G ) – [C – G ( + )] where C = direct signal; M = specular reflected signal power from the sea; G = maximum gain of the receive SES antenna pointing towards the satellite;

= elevation angle and , as is shown in Figure 1 In addition, keeping accuracy sufficient for practical purposes, the previous relation gives:

The relationship between the carrier-to-noise (C/N) ratio and the carrier-to-multipath (C/M) ratio is expressed as C/M = C/N + [G – G(+)], where C/N indicates the deviation of the C/N ratio As the elevation angle decreases, the C/M ratio consistently declines, except between elevation angles of 5° to 8°, where an increase in C/N is noted This anomaly occurs because, at these angles, the path difference between the direct and specular signals becomes minimal, resulting in conditions that resemble the summation of similar signals at the receiver input Additionally, a concurrent rise in the C/N plus M ratio is observed, attributed to a peak in the amplitude of the noise (diffused) component Experimental data indicates that as the elevation angle decreases from 10° to 1°, the mean C/N ratio experiences significant changes.

C/N plus M diminishes from 22–24 dB to 17–18 dB, with the deviation increasing from 1.5–2 dB to 4.5–5 dB

4 MULTIPATH FADING CALCULATION MODEL FOR REFLECTION FROM THE SEA

D Ilcev 19 Yesterday, Today and Tomorrow of the GMDSS

This article discusses the sensitive components of the ship’s antenna tracking system, identified as the weakest link in the Maritime Mobile Satellite Service (MMSS) It outlines the complete components of the Ship Earth Station (SES), including the antenna system, transceiver, and independent control subsystems Maritime Satellite Communications (MSC) utilize large and heavy Mobile Satellite Antennas (MSA), particularly the Inmarsat B and Fleet-77 systems However, advancements over the past two decades have significantly reduced the size and weight of directional antenna systems, which consist of mechanical assemblies, control electronics, gyroscopes, and microwave electronic packages These improvements, driven by increased Effective Isotropic Radiated Power (EIRP) from satellite transponders and advancements in GaAs-FET technology, have facilitated the redesign and installation of shipborne antennas on various platforms, including tracks and airplanes.

5 BDE Diplexer (DIP) – Enables direction of transmitting signals from Modulator to the ADE and receiving signals from ADE to the Demodulator

The ADE is mounted below the waterproof container or radome on the Stabilized Platform The following units compose the ADE assembly:

1 ADE Diplexers (DIP) – The first diplexer passes all transmitting signals to the Up Converter and from Down Converter to the Demodulator The second diplexer guides transmitting signals from

HPA to the SAU and from SAU to the LNA

The Up and Down Converters play a crucial role in communication systems by translating modulated Intermediate Frequency (IF) signals to Radio Frequency (RF) for uplink transmission and vice versa for downlink reception The Up Converter processes the modulated IF carrier from the modulator, mixing it with a Local Oscillator (LO) frequency to generate the uplink RF signal through a High Power Amplifier (HPA) Conversely, the Down Converter receives the modulated RF carrier from the Low Noise Amplifier (LNA) and converts it back to the IF for further processing.

3 High Power Amplifier (HPA) – This unit provides amplification of transmitting signals by the

Traveling Wave Tube Amplifier (TWTA) and

Klystron Amplifier The second HPA enables higher gain and better efficiency than TWTA but in smaller bandwidth of 2% The amplified uplink signal goes via DIP to the SAU

The Low Noise Amplifier (LNA) serves as the initial amplification stage for downlink signals received from the Satellite Antenna Unit (SAU) through a Dual In-line Package (DIP), ensuring minimal additional temperature noise Among the various LNA products available, the most widely utilized are the new Gallium Arsenide (GaAs) Field Effect Transistors (FETs), known for their superior performance in low-noise applications.

Transistor) and old Parametric amplifiers Thus, the recent developed GaAs FET LNA enables very low noise temperatures and takes advantages of its stability, reliability and low cost

5 Antenna Control Unit (ACU) – Antenna Control

The unit offers precise control of the ship's antenna Stabilized Platform and Tracking System, ensuring that the antenna remains accurately directed towards the satellite focus despite any movement of the vessel.

The MSA system is typically installed on a platform featuring two horizontally stabilized axes (X and Y), achieved through gyrostabilizers or sensors like accelerometers and gyrocompasses This stabilization allows for a horizontal plane that remains unaffected by the mobile motion of the vessel, which experiences seven navigational components: roll, pitch, yaw, surge, sway, heave, and turn While turn refers to an intentional change in ship heading, the other six components are influenced by wave motion, with surge, sway, and heave specifically resulting from acceleration.

2.1 Two-Axis Mount System (E/A and Y/X)

An antenna mount is a mechanical system designed to keep the antenna beam directed in a specific orientation In Maritime Mobile Satellite Services (MMSS), the mount must be capable of pointing in any direction across the celestial hemisphere, as ships navigate turbulent seas The two-axis antenna configuration is recognized as the simplest mount that fulfills these requirements.

Figure 2 Components of Ship Motion Courtesy of Book: “Mobile Antenna Systems Handbook” by

Figure 3 Two and Four-axis Mount Systems Courtesy of Book: “Mobile Antenna Systems Handbook” by

The two primary types of mounts in the axis configuration are the E/A (elevation/azimuth) mount and the Y/X mount, illustrated in simplified stick diagrams The E/A mount allows for full steerability by rotating the azimuth axis (A-axis) from 0 to 90 degrees, while the Y/X mount achieves full steerability with rotation angles ranging from -90 to +90 degrees for both the X and Y axes This configuration is essential for ship utility, as it compensates for ship motions caused by sailing and ocean waves, ensuring the antenna beam remains nearly fixed in space For effective pointing and tracking amidst these motions, each axis requires a rotation angle range extending from 0 degrees to beyond the standard limits.

The A-axis offers a full 360-degree rotation, while the E-axis operates within a range of -25 degrees to +120 degrees relative to the deck level, with an operational elevation angle typically limited to above 5 degrees Both types of mounts, however, present various disadvantages.

2.2 Three-Axis Mount System (E/A/X, E’/E/A and

The three-axis mounting system is an enhancement of the modified two-axis mount, incorporating an additional X-axis to mitigate rapid motion caused by roll As illustrated in Figure 4 (A), the E/A mount's X-axis addresses this issue, although it still faces potential gimbal lock for pitch when the E-axis aligns with the X-axis near the zenith Figure 4 (B) depicts the E’/E/A type, which features an extra cross-elevation axis (E) that allows the azimuth angle to be tracked by the A-axis, while the E and E’ axes facilitate movement in two perpendicular directions This configuration effectively eliminates gimbal lock problems near both the zenith and horizon In contrast, the X’/Y/X type, shown in Figure 4 (C), integrates an X’-axis to prevent gimbal lock at the horizon, with the X-axis managing rapid motion due to yaw and turn when the satellite is close to the horizon The X’-axis operates within a ±120° range, addressing rapid motion within that angular limit Overall, this three-axis mount presents greater complexity compared to a four-axis system, as steering and stabilization processes are interdependent.

Figure 4 Three-axis Mount System

Courtesy of Book: “Mobile Antenna Systems Handbook” by

Figure 5 Functional Block Diagrams of Step and Program

Courtesy of Book: “Mobile Antenna Systems Handbook” by

The four-axis mount solution, depicted in Figure 3(C), features a stabilized platform designed to eliminate roll and pitch, along with a two-axis E/A type mount This innovative design enhances tracking accuracy by separating stabilization from steering, allowing for individual control of four key components: roll, pitch, azimuth, and elevation angles As a result, this four-axis mount has been widely implemented in SES antenna systems compliant with the current Inmarsat-A and B standards.

3 ANTENNA TRACKING AND POINTING SYSTEMS

The tracking and pointing system is a crucial component of the antenna mount system For SES tracking MSA systems, the primary requirements are economy, simplicity, and reliability When the antenna beam width is broad, tracking performance becomes a secondary consideration.

Manual tracking is a straightforward technique where an operator adjusts the antenna beam to optimize signal reception The process begins with the operator acquiring the signal and moving the antenna along one axis If the signal strength increases, the operator continues in that direction; if it decreases, they reverse course until the signal is maximized This procedure is then repeated on the second axis, and the antenna is secured once the signal level drops This method is particularly effective for Land Mobile Satellite Communications (LMSC), making it ideal for portable and fly-away terminals.

The 2 Step Tracking system has emerged as an effective antenna-tracking mode for SES terminals, offering a balance of simplicity and moderate tracking accuracy Recent advancements in integrated circuits and microprocessors have significantly reduced costs, making this system more accessible Unlike manual tracking, which relies on human operators, the step track system utilizes an electric controller to automate the process The system employs sample-hold circuits to maintain signal levels, comparing them before and after the antenna moves by a specified angular step If the signal level increases, the antenna continues in the same direction; if it decreases, the direction reverses This method alternates between two axes, with accuracy hinging on the sensitivity of the comparators Consequently, the beam center remains aligned with the satellite's direction, though inaccuracies can arise from factors like S/N ratio fluctuations, multipath fading, and stabilization errors.

Program tracking is a system that utilizes open-loop control linked to automatic navigation equipment like ship gyrocompasses, GPS, and Loran-C systems In this process, the antenna is directed toward a calculated position based on navigation data Due to the satellite's movement caused by roll, pitch, and turning, it is essential to incorporate a function that mitigates rapid motion in the program tracking system.

The navigation equipment error in a program track system is minimal and primarily hinges on the accuracy of sensors measuring roll, pitch, and turn directions, known as stabilization error A vertical gyro is an ideal sensor for this system, as it is largely unaffected by lateral acceleration For less stringent stabilization requirements, conventional level sensors like inclinometers, pendulums, and levels can be utilized, provided the sensor's placement is carefully considered.

Korcz

Furusho, K Kawamoto, Y Yano & K Sakamoto 21 Safety Control of Maritime Traffic Near by Offshore in Time

Kobe University, Graduate School of Maritime Sciences, Kobe, Japan

Kawasaki University of Medical Welfare, Okayama, Japan

Kobe University, Graduate School of Maritime Sciences, Kobe, Japan

The environmental condition of visual acuity is crucial for navigation officers on the bridge, as mandated by the IMO COLREG’s Rule 5, which emphasizes the importance of maintaining a proper look-out to prevent ship collisions Despite good visibility, numerous collision incidents still occur at sea, highlighting the need for enhanced awareness This paper explores two key aspects related to sunlight: illuminance and luminance, which play significant roles in visual perception during navigation.

The first topic is the introductory explanation of the illuminance inside the navigation bridge

The second topic is the sky luminance condition as seen by the OOW from the navigation bridge

Visual perception at sea is crucial, particularly for the Officer of the Watch (OOW) on the bridge It is essential for the OOW to exercise utmost caution, especially during favorable weather conditions.

The illuminance meter (model IM-3 made by

TOPCON Co Ltd utilized a measurement device linked to a recording printer, as shown in Photo 1 The measurement of illuminance on the navigation bridge was conducted without any restrictions, such as changes in course or speed.

Table 1 Specification of the cooperative ships

1) T: Training ship, CF:Car Ferry, H.E.:Height of Eye

2) Observing area was around Japan Latitude: 35degrees N

2.2 Sky luminance in 2 degrees from the horizon

To effectively recognize a target like a ship or navigational aid, it is crucial that the background luminance contrasts significantly with the target For visible perception to occur, the difference in luminance between the background and the target must exceed the luminance difference threshold.

The luminance difference threshold means the threshold limit value of the brightness, based on the experimental studies by Blackwell, H.R., in 1946 and Narisade, K et al, in 1977 and so on

When assessing a target at sea, navigators’ eye movement characteristics provide valuable insights This evaluation considers the sky luminance 2 degrees above the horizon, while the sea surface luminance 2 degrees below the horizon is acknowledged but not emphasized in this study.

The measurement was carried out on board ship

C The luminance meters (TOPCON’s meters BM-5,

The BM-5A and BM-8 luminance meters were positioned and aimed directly through the navigation bridge's windscreen, following standard procedures set by the navigators As detailed in Table 2, the specifications of the BM-5A luminance meter were utilized during this process The weather was favorable, characterized by either clear skies or light cloud cover, with direct sunlight present.

Table 2 Specification of the luminance meter(BM-5A) _

Optical System Diameter 32 mm, F=2.5 Measurement Angle 0.1, 0.2, 1, 2 degrees Photo acceptance Unit Electronic Light Amplifier Wave Length 380-780 n.m

Range 0.0001到 1200000cd/m2 Distance 520mm到

Sampling Time 2 sec Size & Weight 355(L) X 130(W) X 169(H) mm ,

3.1 Horizontal illuminance on the navigation bridge

The measurement data of horizontal illuminance on the navigation bridge, obtained using an illuminance meter connected to a printer, is illustrated in Figure 2 The vertical axis of Figure 2 presents illuminance values in lux on a logarithmic scale, while the horizontal axis represents Japan Standard Time (JST), which is 9 hours ahead of Greenwich Mean Time (GMT) The data exhibits variability due to the differing observation times throughout the month.

Figure 2 Horizontal illuminance in the navigation bridge

3.2 Sky luminance of 2 degrees above the horizon

During a research voyage in July, the luminance of the sky was measured in relation to the solar direction over the open sea The findings of these observations are detailed in Table 3.

Table 3 Sky luminance of the relative direction towards the solar direction at open sea

Relative Angle Max.:A Min.:B Range:A-B degrees cd㸭m 2 cd㸭m 2 cd㸭m 2

Remarks: Relative angle 0 degree means the solar direction

“-(negative number)” means the left side of solar direction

The sky luminance, dependent on the relative direction towards the solar direction at the time of relative angle around 0 (zero) degrees, changes from

7,000 to 27,000 cd/m 2 The range, which means the difference of luminance between the maximum value at A and the minimum value at B, was found to be approximately 20,000 cd/m 2

The opposite side, in the case where the relative angle is -90 ~ +90 degrees of solar direction, produced a small change at 1/10th of the range

Figure 3 Relationship between the sky luminance and the solar altitude in degrees

4.1 Horizontal illuminance by the standardization with using solar altitude

Fig 2 shows the seasonal difference for times of sunrise and sunset; also, the difference in hours of morning or evening twilight at differing sea areas

The height of the observer's eye does not impact the horizontal illuminance on the navigation bridge During the day, illuminance levels range significantly from 1,000 lx to 10,000 lx, whereas during morning and evening twilight, these levels fluctuate rapidly over time This rapid change is a notable characteristic of twilight, as it coincides with functional adjustments in both cone and rod cells of the visual system.

The horizontal illuminance near the windshield on the navigation bridge varies significantly, ranging from 0.01 lx to 10,000 lx, depending on factors such as the seagoing area, time of navigation, and the ship's course.

Seasonal variations in illuminance, influenced by sunrise, sunset, and twilight hours, can complicate the standardization of light measurements To address this challenge, utilizing solar altitude calculations based on specific observation times and geographical locations proves beneficial for achieving consistent illuminance standards.

The results illustrated in Fig 4 indicate that solar altitude effectively explains the variations in horizontal illuminance on the navigation bridge, highlighting its suitability as a key factor in this analysis.

Figure 4 Horizontal illuminance on the navigation bridge by the standardisation method using solar altitudes

To compare luminance levels at sea and on land, this article references illuminance measurements conducted in Fukui Prefecture, Japan, as detailed in the Lighting Handbook published by the Illuminating Engineering Institute of Japan.

Figure 5 illustrates an example with no observational data below 5 degrees on shore In this figure, the line connecting the sun and the observer's zenith on the celestial sphere exhibits bilateral symmetry, with the maximum point indicated as "X" near the sun and the minimum point located 90 degrees away from the zenith.

4.3 Sky luminance at sea in fine weather

Figure 6 illustrates the sky luminance in relation to the solar altitude, with the surrounding numbers representing the relative angles in degrees The radial axes indicate the sky luminance measured in candela per square meter (cd/m²).

Yoon, M Yi, J S Jeong, G K Park & N S Son 22 Maritime Safety in the Strait of Gibraltar Taxonomy and Evolution of Emergencies Rate

SUNY Maritime College and Mokpo National Maritime University

MOERI, Korea Ocean Research and Development Institute

This paper presents a real-time safety strategy for managing vessel interactions, focusing on calculating danger levels based on factors influencing potential collision impact forces It introduces a motion strategy designed to minimize risk and danger factors for vessels with articulated degrees of freedom engaged in multiple activities Simulations and experiments validate the effectiveness of this approach The primary goal of this research is to develop an assistant system that analyzes ship activities in real time from a land-based perspective.

IMO number, Call Sign, Name, Length, Beam,

Type of ship, Location of position-fixing antenna on the ship

Ship’s Position, Time in UTC, Course over ground, Speed over ground, Heading, Naviga- tional status, Rate of turn, Ship’s draught, Haz- ardous cargo, Destination and ETA

Figure 2 Integrated Service System Using AIS

This paper utilizes a meaning analysis model that organizes data fields related to navigation gear and target-specific knowledge The model effectively conveys simple sentences Furthermore, it demonstrates a meaning analysis framework tailored for designed navigational equipment, presenting a comprehensive model for target interpretation.

Case 1: If target is ship or vessel,

By utilizing ARPA, AIS, and VHF, valuable information can be gathered This approach integrates the data from these systems for effective meaning analysis, as illustrated in the accompanying figure.

Figure 3 Model of Meaning Analysis: If target is Vessel

In cases where the target is not a ship or vessel, the meaning analysis model integrates information from ARPA and NAVTEX, as obtaining data from AIS and VHF is not feasible This approach is illustrated in the accompanying figure.

Figure 4 Model of Meaning Analysis: If target is Other Than Vessel

1 The view of intelligent safety information system and discrete event system

Step of unit filtering and recognition: need to analyze data coming up in real time

Step of expecting situation: need to check out in terms of discrete event system

Figure 5 Navigation Information Mixing System by Discrete

System Draft for Expecting Safety Situation

G Figure 6 Draft of Simulation Module for Expecting Situation

Input Factors: Current Navigation Situation

Output Factors: Future Navigation Situation

Inside Unit: Instant Structured Model for Dy- namic Change of Situation

2 Three Knowledge Base including Behavioral Base, Structural Base ( Behavioral Base SES(System Entity Structure)), Regulation Base

Two Inside Process for Structured Model Genera- tion and Simulation Process

Blocking area theory is useful for preventing collisions with individual ships but struggles to manage multiple concurrent traffic in real maritime conditions Simulator experiments reveal that collision risk can typically be assessed using fuzzy algorithms, showing a similar pattern of environmental stress in both open seas and confined waterways, as illustrated in Figure 7.

Figure7 Model Research for Risk Level of Ship Collision

Figure 8 illustrates an assessment algorithm that evaluates collision risk, essential for safe ship movement planning and control Utilizing marine traffic data, the interrelated model is summarized and depicted in Figure 9.

Identification Model for Degree of Collision Risk

Figure 8 Flow Chart and Draft of Assessment Algorism of Degree of Collision Risk

Figure 9 Chart of Assessment Algorism of Degree of Collision Risk

3 TEST RESULT FOR RISK ASSESSMENT

This research presents the test results of comprehensive conceptual models aimed at validating the risk assessment model for environmental conditions surrounding vessels The structure of the testing process is illustrated in the figure below.

Dotted line is to be designed Experimental frame’s

The generator supplies random environmental data for output verification During the pre-processing stage, this data is treated to ensure clarity and understanding Subsequently, the processed input data is utilized to calculate the risk assessment results for each parameter using a fuzzy professional system Ultimately, the Total_ERAN process provides users and sailors with insights into the overall collision risk degree and individual unit risk levels.

Figure 10 Chart of Test System

The experimental results demonstrate the implementation of a generator for both random situations and assumed scenarios The database, particularly the environment database, plays a crucial role in real-time information management, containing a predefined list of environmental risks associated with activated equipment In this study, real-time environmental data generated by the system are utilized to explore a conceptual model The results from the environmental risk assessment, derived from random cases, contribute to maritime safety information that is integrated with the General Information Center on Maritime Safety & Security (GICOMS) This integration allows for the evaluation of effectiveness and the enhancement of services required by governmental and private sectors By providing essential information to government agencies and companies, the system aims to improve safety for crew, cargo, and vessels through pre-emptive alerts for accident-prone and hazardous areas, while also safeguarding personal and national information via the GICOMS operational security system.

This study develops an innovative platform that combines various theories and methodologies to enhance vessel safety systems, aiming to ensure the safety, security, and comfort of occupants by preventing collisions It introduces a real-time model for monitoring ship safety during interactions, defining the level of danger associated with potential collisions as a danger characteristic Additionally, a sequential one-step ahead trajectory planner is proposed, which minimizes this danger characteristic to generate vessel motion effectively This algorithm is versatile, functioning accurately across all vessel configurations, whether for redundant or non-redundant manipulators.

[1] A Bicchi, S L Rizzini, and G Tonietti, "Compliant design for intrinsic safety: General Issues and Preliminary De- sign," presented at IEEE/RSJ Int Conf on Intelligent Ves- sel and Systems, pp 1864- 1869, 2001

[2] A J Bearveldt, "Cooperation between Man and Vessel: In- terface and Safety," presented at IEEE Int Workshop on

[3] B Martinez-Salvador, A P del Pobil, and M Perez-

Francisco, "A Hierarchy of Detail for Fast Collision Detec- tion," presented at IEEE/RSJ Int Conf on Intelligent Ves- sel and Systems, pp 745-750, 2000

[4] N.S Son, S.Y Kim, J.Y Oh, “STUDY ON AN ALGO-

RITHM FOR THE ESTIMATION OF COLLISION RISK

AMONG SHIPS BY USING AIS DATABASE”, Proceed- ings of 9th Asian Conference on Marine Simulator and

[5] J Zurada, A L Wright, and J H Graham, "A Neuro-Fuzzy

Approach for Vessel System Safety," IEEE Transactions on

Systems, Man and Cybernetics - Part C: Applications and

[6] J Y Lew, Y T Jou, and H Pasic, "Interactive Control of

Human/Vessel Sharing Same Workspace," presented at

IEEE/RSJ Int Conf on Intelligent Vessel and Systems, pp

In their 2009 study published in the Journal of Korean Society for Marine Environmental Engineering, N S Son and colleagues explored a collision avoidance algorithm designed for navigating multiple traffic ships The research focuses on a changeable action space searching method to enhance maritime safety and efficiency Their findings contribute valuable insights into the development of advanced navigational systems for complex marine environments.

[8] Mira Yi, Gyei-Kark Park, and Jongmyeon Jeong, "DEVS Approach for Navigation Safety Information System", In- ternational Conference on Electronics, Information, and Communication, 2010

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[10] P I Corke, "Safety of advanced vessel in human environments,"Discussion Paper for IARP, 1999

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[13] Y Yamada, Y Hirawawa, S Huang, Y Umetani, and K Suita, "Human - Vessel Contact in the Safeguarding Space," IEEE/ASME Transactions on Mechatronics, vol 2, pp 230-236, 1997

[14] Y Yamada, T Yamamoto, T Morizono, and Y Umetani,

"FTABased Issues on Securing Human Safety in a Hu- man/Vessel Coexistance System," presented at IEEE Sys- tems, Man and Cybernetics SMC'99, pp 1068-1063, 1999

[15] Y Yamada, Y Hirawawa, S Huang, Y Umetani, and K Suita, "Human - Vessel Contact in the Safeguarding Space," IEEE/ASME Transactions on Mechatronics, vol 2, pp 230-236, 1997

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"Making Service Vessel Human-Safe," presented at IEEE/RSJ Int Conf on Intelligent Vessel and Systems (IROS 2000), pp 696-701, 2000.

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Safety at Sea International Recent Issues about ECDIS, e-Navigation and Safety at Sea – Marine Navigation and Safety of Sea Transportation – Weintrit (ed.)

Coastal states play a crucial role in ensuring the safety of human life, the environment, and property in maritime navigation within their jurisdiction This commitment is reflected in various international legal frameworks that highlight their responsibilities and rights in safeguarding these essential aspects of maritime activities.

The International Convention on Maritime Search and Rescue (SAR'79), established in Hamburg in 1979, along with the United Nations Convention for the Law of the Sea, adopted in Montego Bay, Jamaica in 1982, are key legal instruments governing maritime operations and safety.

These two fundamental legal instruments lay down both regulatory and technical aspects of the development of reactive response to maritime emergencies

Both texts outline the principle of dividing maritime waters, designating specific areas of responsibility for maritime search and rescue for each coastal nation These nations must allocate dedicated human, technical, and legal resources to fulfill the obligations arising from their commitments.

Although both conventions regulate the commitments related to maritime search and rescue matters undertaken by the parties, the International

Convention on Maritime Search and Rescue,

The SAR'79 Convention, established in Hamburg in 1979 and joined by Spain in 1993, outlines essential guidelines for coastal states' authorities in the development and execution of maritime search and rescue services.

Over the years, this agreement has been amended a number of times Among the amendments which are due to be highlighted, we find those adopted in

Stupak & S urkiewicz 26 Studying Probability of Ship Arrival of Yangshan Port with AIS (Automatic Identification System)

Gdynia Maritime University, Gdynia, Poland

Shanghai Maritime University and Gdynia Maritime University have collaborated on a research program called “Online Detecting and Publishing of Congested Zones at Sea.” This initiative aligns with the e-Navigation concept proposed by IALA The authors aim to identify the user requirements for the Congested Area Detection and Projection System.

In accordance to IMO requirements, maritime states, including China and Poland have introduced Marine

Traffic Monitoring Systems utilizing shore based and ships based devices of automatic identification,

(AIS) This system facilitates the real time movement monitoring of the vessels fitted in devices of

AIS Class A and Class B devices serve different purposes in maritime navigation AIS Class A devices, designed for larger ships, transmit vital information such as geographical position, movement vector, declared draught, port of destination, and optional voyage plans, with data entered manually by navigating officers In contrast, AIS Class B devices, intended for fishing vessels and smaller crafts, transmit less frequent information, primarily focusing on position and movement vector, without the availability of declared information.

Poland, implementation of such system had been required by Copenhagen Declaration and EC Directive

2002/59, similarly as for remaining Baltic Sea EU member states

Currently, marine traffic monitoring in Polish waters relies on passive data recording By fully utilizing and processing this information, and making it accessible in a user-friendly format in line with the e-Navigation concept, we can enhance navigation safety and contribute to marine environmental protection.

2.3 Marine Safety Information Exchange System

Poland, like other EU maritime nations, has established a Marine Safety Information Exchange System in line with IMO COMSAR/Circ.15, dated March 9, 1998, utilizing AIS technology alongside its Marine Traffic Monitoring System.

The PL network enhances maritime safety by enabling VTS operators to transmit real-time marine safety information and local warnings to vessels through an AIS base station The Polish AIS system (AIS-PL) comprises 11 land-based stations, including 8 for marine and 3 for inland navigation, all connected to a national server that integrates with the HELCOM network.

Although stations spatial distribution was designed to broadcast VHF signals in A1 zone, the whole Polish responsibility area is not permanently covered (Fig 1)

To ensure traffic surveillance and maritime safety, specific system performance levels were established Effective AIS coverage is influenced by weather and pressure conditions, with rare instances of anomalous propagation extending VHF range significantly—sometimes from 35 to 200 miles, allowing access to the opposite side of the Baltic Major traffic areas, such as VTS Zatoka Gdanska and VTMS Zatoka Pomorska, are equipped with additional coverage redundancy to mitigate the impact of system outages or poor propagation, featuring alternative base stations and supplementary communication links.

Fig 1 AIS-PL base stations estimated signal ranges [3]

AIS-PL base stations ranges

Fig.2 South Baltic Sea traffic flow pattern recorded by AIS PL form 1 st to 7 th August 2007 [2]

2.4 Information available to Marine Traffic

The information obtained from AIS for ships is largely similar to that provided by VTS stations; however, the number of ships transmitting this information varies This discrepancy arises from the limited transmission range of AIS class B devices and the enhanced capabilities of VTS stations, which can leverage their own receiving antenna systems and access additional AIS data from other VTS stations.

VTS centers possess access to extensive information that encompasses a larger area than individual ships can cover In Poland, the National Marine Safety System is undergoing reconstruction, which will enhance VTS capabilities by integrating additional data from cameras and shore radar stations.

The Figure 2 demonstrates current possibilities of obtaining and recording traffic information by AIS

Data recorded by AIS PL might be used for purpose of joint SMU-GMU project

Unlike VTS stations, ships can closely observe objects that are not equipped with AIS devices, which may not be visible to cameras or shore-based radar systems Consequently, the exchange of information becomes crucial for ensuring safe navigation and protecting the environment.

2.5 SMU-GMU joint project description

The main goal of joint SMU-GMU research is to design identification, prediction, and real time projection algorithmic models of congested area

The figure 3 presents basic idea of the system, as proposed by the authors of this paper

Figure 3 Congested Area Detection and Projection – VTS Mode, Basic Idea

The initial scientific challenge involves defining and constructing a mathematical model for congested areas Given the unique traffic flow patterns in Chinese and Polish waters, each research team aims to identify congested areas through distinct methodologies.

Chinese research team, by utilizing DBSCAN algorithm and the fuzzy modelling distance match- ing criterion,

A Polish research team has developed a method for planning vessel movement routes by utilizing data from the Automatic Identification System (AIS) and applying a variant of evolutionary algorithms, all while adhering to collision avoidance criteria.

The Polish team's definition of congestion necessitates predicting vessel positions over an extended time horizon, highlighting the need to incorporate a prediction feature into the system's fundamental concept.

Figure 4 Congested Area Detection and Projection – VTS

Following tasks will to be performed by GMU research team:

1 Conduct surveys on the movement of vessels in

Polish maritime areas and development of:

Procedures for on-line tracking of vessels under the AIS information

Assumptions algorithm modelling areas with particularly high density of maritime traffic through the planning of routes of movement of ships

Develop and implement models for ship passage routes within environments that feature both static and dynamic constraints Utilize information from the AIS to create and enhance alternative evolutionary algorithms for effective vessel path planning.

3 Develop heuristics analyzing changes in the environment and reasoning on action, the selection of operators, exploration and exploitation of a set of solutions

4 Investigate the simulation and test variants of evolutionary algorithms of traffic flow on the basis of different variants of information from the

AIS in Polish maritime areas

5 Analyze and elaborate results of evolutionary algorithms of traffic flow and identification of congested areas or with particularly high density of maritime traffic

The GMU project aims to enhance traffic information management by enabling the VTS station to obtain, process, and display data in a user-friendly format, making VTS the primary user of the system Additionally, to meet e-Navigation requirements, the authors recommend that the system should provide both region-specific information for all ships and tailored information for individual vessels.

This would require that system has to process data in both, VTS and Own Ship mode See Figure 5

Figure 5 Congested Area Detection and Projection – VTS &

The system utilizes processed data to display congested areas on the navigation bridge in real-time, based on selected criteria It also provides early warnings of potential collision threats that may arise in a specific region or along the track of a single vessel.

Tiêu đề	International Recent Issues about ECDIS, e-Navigation and Safety at Sea
Tác giả	Adam Weintrit
Trường học	Gdynia Maritime University
Chuyên ngành	Marine Navigation and Safety of Sea Transportation
Thể loại	edited book
Năm xuất bản	2011
Thành phố	Gdynia

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Số trang	201
Dung lượng	3,77 MB