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Wyświetlanie 1-6 z 6
Tytuł:
Efficiency of a voluntary speed reduction algorithm for a ship’s great circle sailing
Autorzy:
Wang, H.
Mao, W.
Eriksson, L.
Powiązania:
https://bibliotekanauki.pl/articles/117253.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
great circle sailing
algorithm, ship’s sailing route
route planning
Dynamic Programming (DP)
great circle route
great circle (orthodrome)
Estimated Time of Arrival (ETA)
Opis:
The great-circle is the shortest distance between two points on the surface of the earth. When planning a ship’s sailing route (waypoints and forward speeds) for a specific voyage, the great circle route is commonly considered as a reference route, especially for ocean-crossing seaborne transport. During the planning process, the upcoming sea weather condition is one of the most important factors affecting the ship’s route optimization/planning results. To avoid encountering harsh conditions, conventional routing optimization algorithms, such as Isochrone method and Dynamic Programming method, have been developed/implemented to schedule a ship’s optimal routes by selecting waypoints around the great circle reference route based on the ship’s operational performances at sea. Due to large uncertainties in sea weather forecast that used as inputs of these optimization algorithms, the optimized routes may have worse performances than the traditional great circle sailing. In addition, some shipping companies are still sailing in or making charting contracts based on the great circle routes. Therefore, in this study, a new optimization algorithm is proposed to consider the voluntary speed reduction with optimal speed configuration along the great circle course. The efficiency of this method is investigated by comparing these two methods for optimal route planning with respect to ETA and minimum fuel consumption. A container ship sailing in the North Atlantic with full-scale performance measurements are employed as the case study vessels for the comparison.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 2; 301-308
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wind influence on ship manoeuvrability – a turning circle analysis
Autorzy:
Novaselic, M.
Mohovic, R.
Baric, M.
Grbić, L.
Powiązania:
https://bibliotekanauki.pl/articles/1841564.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
shipm anoeuvrability
turning circle
Safety at Sea
vessel trajectory
wind influence
wind force
manoeuvrability characteristics
ship's turning
Opis:
Ship manoeuvrability is a wide term which consist of number of various parameters. Knowing the influence of these parameters on ship manoeuvrability is a first condition to ensure and maintain safe navigation. However, many of these parameters are external forces and, in some cases, cannot be calculated and prediction may be complicated. Analysing the influence of external forces can give as an insight into ship manoeuvrability when such external force occurs. The main purpose of this paper is to analyse the influence of wind on ship manoeuvrability. The best way to make such analysis is during turning circle because in this case wind acts in all 360°. Analysis is made using empirical equations and in situ with the real vessel. The results provide the better understanding of vessel trajectory and show that in some cases vessel may respond in unexpected manner.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 1; 47-51
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using GIS to obtain Celestial fix under the framework of an ECDIS System
Autorzy:
Tsou, M. C.
Powiązania:
https://bibliotekanauki.pl/articles/1841602.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
ECDIS
Geographic Information System
GIS
celestial fix
circle of position
Intercept Method
dead reckoning
two-body fix
astronavigation
Opis:
This study proposes a simple method for obtaining a celestial fix, developed within a Geographic Information System (GIS) under the framework of an ECDIS system. The underlying principle is dependent on the most fundamental theory in celestial navigation; the circle of position (COP) of the celestial bodies is plotted to find the fix. Through the spatial data processing, analysis, and visualization capabilities available in GIS, a celestial fix may be obtained directly from plotting. This eliminates the limitations associated with finding the fix manually using a paper map, but also avoids the cumbersome work and inaccuracy of the traditional Intercept Method (IM) or the complicated, and often obscured, computation involved in numerical methods. The proposed method is simple and accurate, and it applies to problems involving two or more celestial bodies and high-altitude observations. It provides a reference for the development of a celestial positioning module in an ECDIS system, and could also be integrated into an educational program on electronic celestial navigation.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 3; 675-680
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of Ship Maneuvering Model Using Extended Kalman Filters
Autorzy:
Shi, C.
Zhao, D.
Peng, J.
Shen, C.
Powiązania:
https://bibliotekanauki.pl/articles/116777.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Manoeuvring
Ship Manoeuvering Model
Kalman filter
extended Kalman filter (EKF)
Ship Manoeuvrability
ship handling simulator
Turning Circle Test
Zig-Zag Test
Opis:
Ship maneuvering models are the keys to the research of ship maneuverability, design of ship motion control system and development of ship handling simulators. For various frames of ship maneuvering models, determining the parameters of the models is always a tedious task. System identification theory can be used to establish system mathematical models by the system’s input data and output data. In this paper, based on the analysis of ship hydrodynamics, a nonlinear model frame of ship maneuvering is established. System identification theory is employed to estimate the parameters of the model. An algorithm based on the extended Kalman filter theory is proposed to calculate the parameters. In order to gain the system’s input and output data, which is necessary for the parameters identification experiment, turning circle tests and Zig-zag tests are performed on shiphandling simulator and the initial data is collected. Based on the Fixed Interval Kalman Smoothing algorithm, a pre-processing algorithm is proposed to process the raw data of the tests. With this algorithm, the errors introduced during the measurement process are eliminated. Parameters identification experiments are designed to estimate the model parameters, and the ship maneuvering model parameters estimation algorithm is extended to modify the parameters being estimated. Then the model parameters and the ship maneuvering model are determined. Simulation validation was carried out to simulate the ship maneuverability. Comparisons have been made to the simulated data and measured data. The results show that the ship maneuvering model determined by our approach can seasonably reflect the actual motion of ship, and the parameter estimation procedure and algorithms are effective.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2009, 3, 1; 105-110
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Research of Northern Labyrinths as Navigation Network Elements
Autorzy:
Paranina, A.N.
Paranin, R.
Powiązania:
https://bibliotekanauki.pl/articles/117170.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Northern Labyrinths
megalithic sites
gnomon
navigational instruments
information model of the world (IMW)
navigation network
arctic circle
history of navigation
Opis:
The authors of the article consider the stone labyrinths as solar calendars. In the center of these structures there are usually already installed gnomons – vertical objects that give shade. Midday shadow points to north, and the change of its length during a year is correlated with the diameter of the arcs of the labyrinth. Points of sunrise / sunset at the equinoxes and solstices are very often fixed in the pattern of the labyrinth, as well as the beginning of the annual cycle. In general, patterns of labyrinths are of the same type, the differences reflect the regional characteristics of illumination, the differences in latitude and topography (shape of the horizon). The uniformity of the technology and the location on the waterways give an opportunity to consider stone labyrinths as ancient elements of local and regional navigation networks.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2016, 10, 3; 451-456
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ship collision avoidance decision model and simulation based on collision circle
Autorzy:
Zhang, J.
Hu, Q.
Liao, B.
Powiązania:
https://bibliotekanauki.pl/articles/116588.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
collision avoidance
anti-collision
collision circle
decision model
ship collision avoidance decision model
Possible Point of Collision (PPC)
Java Topology Suite (JTS)
colregs
Opis:
In order to give consideration to both comprehensive evaluation and efficient decision-making in collision avoidance decision-making process, a collision avoidance decision-making model based on collision circle is proposed by introducing the concept of collision circle. Firstly, the factors causing ship collision are analyzed. Secondly, the static and dynamic characteristics of collision circles are analyzed and summarized by using collision circle simulation cases. Thirdly, based on the static characteristics, a reasonably distributed collision avoidance decision model of (Possible Point of Collision,PPC) was established. Finally, the spatial data operations core algorithm (Java Topology Suite, JTS) is used for logical operation and visualization, so as to realize the ship collision avoidance evaluation and decision. The decision model was used to verify the accident scenario of "SANCHI", and the results showed that the obtained collision avoidance scheme was reasonable and in line with the "International Regulations for Preventing Collisions at Sea" and safety requirements, thus providing a reference for maritime operators to avoid collisions between ships.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 2; 325-334
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-6 z 6

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