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A method and a model for risk assessment of GNSS utilisation with a proof-of-principle demonstration for polar GNSS maritime applications

Malić E., Sikirica N., Špoljar D., Filjar R.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2023

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Vol. 17 No. 1

43--50

EN

The GNSS positioning performance is commonly defined and described in terms unspecified to particular GNSS-based application. The approach causes difficulties to GNSS application developers, operators, and users, rendering the impact assessment of GNSS performance on the GNSS application Quality of Service (QoS) particularly difficult. Here the Probability of Occurrence (PoO) Model is introduced, which allows for a risk assessment of the probability for the GNSS positioning accuracy failure to meet the requirements of the particular GNSS-based application. The proposed PoO Model development procedure requires a large set of position estimation errors observations, which shall cover a range of classes of positioning environment (space weather, troposphere, multi-path etc.) disturbances affecting GNSS positioning accuracy. As result, the PoO Model becomes a tool that returns the probability of failure in meeting the positioning accuracy requirements of the GNSS applications considered, thus providing the input for a GNSS deployment risk assessment. The proposed PoO Model and its development procedure are demonstrated in the case of polar region positioning environment, with raw GNSS pseudorange observations taken at the International GNSS Service (IGS) Network reference station Iqualuit, Canada are used for the PoO Model development. The PoO Model proof-of-principle is then used to estimate the probability of the unmet required positioning accuracy for a number of polar maritime navigation applications. Manuscript concludes with a discussion of the PoO Model benefits and shortcomings, a summary of contribution, and intentions for the future research.

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Principles of vessel route planning in Ice on the Northern Sea Route

Pastusiak T.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2016

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Vol. 10, no. 4

587--592

EN

A complex of ice cover characteristics and the season of the year were considered in relation to vessel route planning in ice-covered areas on the NSR. The criteria for navigation in ice - both year-round and seasonal were analyzed. The analysis of the experts knowledge, dissipated in the literature, allowed to identify some rules of route planning in ice-covered areas. The most important processes from the navigation point of view are the development and disintegration of ice, the formation and disintegration of fast ice and behavior of the ice massifs and polynyas. The optimal route is selected on basis of available analysis and forecast maps of ice conditions and ice class, draught and seaworthiness of the vessel. The boundary of the ice indicates areas accessible to vessels without ice class. Areas with a concentration of ice from 0 to 6/10 are used for navigation of vessels of different ice classes. Areas of concentration of ice from 7/10 up are eligible for navigation for icebreakers and vessels with a high ice class with the assistance of icebreakers. These rules were collected in the decision tree. Following such developed decision-making model the master of the vessel may take decision independently by accepting grading criteria of priorities resulting from his knowledge, experience and the circumstances of navigation. Formalized form of decision making model reduces risk of the "human factor" in the decision and thereby help improve the safety of maritime transport.

3

Maritime Situation Monitoring for Safe Navigation on Northern Sea Route

Popovich V.V., Smirnova O.V., Popovich T.V.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2016

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Vol. 10, no. 3

433--440

EN

Considering growing intensity of navigation on Northern Sea Route and of continuous exploration and development of Arctic shelf, problems of maritime situation monitoring in Arctic become particularly important. Firstly, complex operational informational support of activities in Arctic is needed. Secondly, constant access to actual and valid information about hydro-meteorological, navigational and ice situations is required. Solution of stated problems entails integration, processing and analysis of large amounts of heterogeneous data. Consequently, development of unified system for situation monitoring and intellectual support is essential. Such system allows to execute operational monitoring of dangerous situations of different sort (natural or anthropogenic) that influence safety of objects in Arctic region, and to perform intellectual analysis of such situations and prompt provision of suitable recommendations.