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Tytuł:
Ship Collision Avoidance by Distributed Tabu Search
Autorzy:
Kim, D.
Hirayama, K.
Okimoto, M.
Powiązania:
https://bibliotekanauki.pl/articles/116919.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Safety of Navigation
Collision Avoidance
Distributed Tabu Search Algorithm (DTSA)
Distributed Local Search Algorithm (DLSA)
Quasi-Local Minimum (QLM)
Tabu Search Algorithm
Local Search Algorithm
Distributed Tabu Search
Opis:
More than 90% of world trade is transported by sea. The size and speed of ships is rapidly increasing in order to boost economic efficiency. If ships collide, the damage and cost can be astronomical. It is very difficult for officers to ascertain routes that will avoid collisions, especially when multiple ships travel the same waters. There are several ways to prevent ship collisions, such as lookouts, radar, and VHF radio. More advanced methodologies, such as ship domain, fuzzy theory, and genetic algorithm, have been proposed. These methods work well in one-on-one situations, but are more difficult to apply in multiple-ship situations. Therefore, we proposed the Distributed Local Search Algorithm (DLSA) to avoid ship collisions as a precedent study. DLSA is a distributed algorithm in which multiple ships communicate with each other within a certain area. DLSA computes collision risk based on the information received from neighboring ships. However, DLSA suffers from Quasi-Local Minimum (QLM), which prevents a ship from changing course even when a collision risk arises. In our study, we developed the Distributed Tabu Search Algorithm (DTSA). DTSA uses a tabu list to escape from QLM that also exploits a modified cost function and enlarged domain of next-intended courses to increase its efficiency. We conducted experiments to compare the performance of DLSA and DTSA. The results showed that DTSA outperformed DLSA.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2015, 9, 1; 23-29
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Learning Search Algorithms: An Educational View
Autorzy:
Janota, M.
Šimák, V.
Hrbček, J.
Powiązania:
https://bibliotekanauki.pl/articles/116502.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Search Algorithm
Learning Search Algorithms
educational view
Artificial Intelligence Method
Search Method
Labyrinth
Dijkstra algorithm
Opis:
Artificial intelligence methods find their practical usage in many applications including maritime industry. The paper concentrates on the methods of uninformed and informed search, potentially usable in solving of complex problems based on the state space representation. The problem of introducing the search algorithms to newcomers has its technical and psychological dimensions. The authors show how it is possible to cope with both of them through design and use of specialized authoring systems. A typical example of searching a path through the maze is used to demonstrate how to test, observe and compare properties of various search strategies. Performance of search methods is evaluated based on the common criteria.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2014, 8 no. 4; 565-570
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of the potential effectiveness of the WIG craft in search action at sea using SARMAP software
Autorzy:
Małyszko, M.
Powiązania:
https://bibliotekanauki.pl/articles/116819.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
aviation
SARMAP
Wing in Ground (WIG)
WIG craft
search action
IAMSAR manual
International Aeronautical and Maritime Search and Rescue Manual (IAMSAR)
Search and Rescue (SAR)
Opis:
Selection and choice of search and rescue units is an important stage in planning SAR operations at sea. The different characteristics of units enable them to be used for specific tasks at sea to varying ranges. The main advantage of WIG crafts is their speed, but they also have other features necessary for marine rescue. The assessment of the unit's potential effectiveness is based, among other things, on defining and determining the parameters influencing its ability to achieve success. Computer software such as SARMAP can be used for action planning. The article contains calculations for simulated actions of searching for several objects, additionally a graphical solution of the situation has been shown.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 2; 437-442
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Derivative free optimal thrust allocation in ship dynamic positioning based on direct search algorithms
Autorzy:
Valčić, M.
Prpić-Oršić, J.
Powiązania:
https://bibliotekanauki.pl/articles/116991.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
algorithm
dynamic positioning
direct search algorithms
sequential quadratic programing (SQP)
Singular Values Decomposition (SVD)
Lagrangian Multiplier Method (LMM)
Direct Search (DS)
Mesh Adaptive Direct Search (MADS)
Opis:
In dynamic positioning systems, nonlinear cost functions, as well as nonlinear equality and inequality constraints within optimal thrust allocation procedures cannot be handled directly by means of the solvers like industry-standardized quadratic programing (QP), at least not without appropriate linearization technique applied, which can be computationally very expensive. Thus, if optimization requirements are strict, and problem should be solved for nonlinear objective function with nonlinear equality and inequality constraints, than one should use some appropriate nonlinear optimization technique. The current state-of-the-art in nonlinear optimization for gradient-based algorithms is surely the sequential quadratic programing (SQP), both for general applications and specific thrust allocation problems. On the other hand, in recent time, one can also notice the increased applications of gradient-free optimization methods in various engineering problems. In this context, the implementation of selected derivative free direct search algorithms in optimal thrust allocation is proposed and discussed in this paper, and avenues for future research are provided.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 2; 309-314
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Adaptation of an Algorithm of Search and Rescue Operations to Ship Manoeuvrability
Autorzy:
Kasyk, L.
Pleskacz, K.
Powiązania:
https://bibliotekanauki.pl/articles/116946.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
search and rescue (SAR)
Ship Manoeuvrability
Algorithm
Search and Rescue Operations
Hydrometeorological Conditions
IAMSAR
SAR Action Algorithm
ECDIS
Opis:
This article presents an overview of an algorithm to facilitate action when planning search and rescue operations, taking into account actual hydro-meteorological conditions and the maneuverability of ships involved in the search.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2015, 9, 2; 265-268
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model of the Search and Rescue operations in Republic of Serbia
Autorzy:
Šoškić, S.
Ćurčić, J.
Karapetrović, L.
Powiązania:
https://bibliotekanauki.pl/articles/116341.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
search and rescue (SAR)
SAR Operation
IAMSAR Manual
Rescue Coordination Centre (RCC)
Search and Rescue Sub-Region (SRS)
SAR in Republic of Serbia
Search and Rescue Unit (SRU)
Water Course Traffic Service (WTS)
Opis:
The IAMSAR Manual contains practical guidelines for the organisation of maritime and aeronautical SAR, mission coordination, operations of search and rescue units (SRUs) and provision of SAR-related training. RCC (rescue coordination center) - a unit responsible for promoting efficient organization of search and rescue operations within a search and rescue region. Rescue Coordination Centre (RCC) means a designated coordination centre that acts as the national Search and Rescue Region's coordination centre and the international point of contact for search and rescue (SAR) services and that takes care of the continuous maintenance of coordination and communication preparedness and coordinates SAR operations within its Search and Rescue Sub-Region (SRS). Definition of tearms Search: An operation, normally coordinated by a RCC or RSC, using available personnel and facilities to locate persons in distress. (IAMSAR, Volume 1). Definition of terms Rescue: An operation to retrieve persons in distress, provide for their initial medical or other needs and deliver them to a place of safety. Work should contribute to the establishment of thinking for model of SAR in Republic of Serbia due to the growing need of interventions in the prevention and elimination of consequences of natural disasters and better organization of search and rescue using the standards prescribed in the the world.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2015, 9, 2; 269-277
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Saving migrants from the sea: improving training for search and rescue operations
Autorzy:
Radojević, S.
Kresojević, M.
Powiązania:
https://bibliotekanauki.pl/articles/116881.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Maritime Education and Training (MET)
saving migrants
saving migrants from the sea
Search and Rescue (SAR)
search and rescue operations
maritime search and rescue
IAMSAR
situation
mission
execution
administration and logistics
command
control and communication SMEA
Opis:
This paper presents a research in the field of maritime training and education for Search and Rescue (SAR) migrants at sea. This research is oriented to more effective method based on team training for SAR Operations utilizing ship simulation and process of Operational Planning. The training which conducts in cabinets and ship simulators at the Military Academy provides the best results in the optimal application of onboard and emergency/SAR procedures. The training method is in line with all conventions of the International Maritime Organization and models of maritime training courses. The proposed training method can be developed and applied in all schools and centers where seafarers and other Maritime Search and Rescue personnel are trained.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2020, 14, 1; 129-133
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implementation of the multifunctional communication system for RIS center supporting Inland Navigation
Autorzy:
Lisaj, A.
Powiązania:
https://bibliotekanauki.pl/articles/2063977.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
River Information System
Iridium Satellite System
RIS Center
Multifunctional Communication System
GMDSS
DSC Communication
Search and Rescue
Opis:
The article presents the feasibility of implementation integrated digital and analog radio-communications systems in maritime and inland navigation at the RIS Center. Structure of the date transmission in the RIS system was characterized. Integration of the Iridium Satellite System into a Multifunctional Communication System for the RIS Centre was presented. The integrating DSC VHF and DSC MF GMDSS subsystems with Multifunctional Communication System was presented. The possibilities of integrating The LT- 3100S Lars Thrane module for Multifunctional Communication System. was presented. The architecture of Multifunctional Communication Systems implementing distress communication procedures in cooperation between RIS Center and Search and Rescue Centers was presented.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 3; 605--608
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Innovative Liferaft
Autorzy:
Abramowicz-Gerigk, T.
Burciu, Z.
Jachowski, J.
Kornacka, E.
Stefurak, W.
Powiązania:
https://bibliotekanauki.pl/articles/116208.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
liferaft
search and rescue (SAR)
liferaft constuction
Life Saving Applinces (LSA)
liferaft detection
radar detection
reflective material
liferaft characteristics
Opis:
The paper present the latest results of researcg carried out within R&D project on new solutions of liferaft constuction. CFD simulations of liferaft performance are presented.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2015, 9, 4; 573-577
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aggregating sea surface hydrodynamic forecasts from multi-models for European seas
Autorzy:
Frishfelds, V.
She, J.
Murawski, J.
Nielsen, J. W.
Powiązania:
https://bibliotekanauki.pl/articles/24201473.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
weather research and forecasting
search and rescue
operational ocean forecasting
European Satellite Systems
surface current
drifting sea surface temperature
European waters
Opis:
Maritime information services supporting European agencies such as the FRONTEX require European‐wide forecast solutions. Following a consistent approach, regional and global forecasts of the sea surface conditions from Copernicus Marine Service and national met‐ocean services are aggregated in space and time to provide a European‐wide forecast service on a common grid for the assistance of Search and Rescue operations. The best regional oceanographic model solutions are selected in regional seas with seamless transition to the global products covering the Atlantic Ocean. The regional forecast models cover the Black Sea, Mediterranean Sea, Baltic Sea, North Sea and combine the North Sea – Baltic Sea at the Danish straits. Two global models have been added to cover the entire model domain, including the regional models. The aggregated product is required to have an update frequency of 4 times a day and a forecasting range of 7 days, which most of the regional models do not provide. Therefore, smooth transition in time, from the shorter timerange, regional forecast models to the global model with longer forecast range are applied. The set of parameter required for Search and Rescue operations include sea surface temperature and currents, waves and winds. The current version of the aggregation method was developed for surface temperature and surface currents but it will be extended to waves in latter stages. The method relies on the calculation of aggregation weights for individual models. For sea surface temperature (SST), near real‐time satellite data at clear‐sky locations for the past days is used to determine the aggregation weights of individual forecast models. A more complicated method is to use a weighted multi‐model ensemble (MME) approach based on best forecast features of individual models and possibly including near real time observations. The developed method explores how satellite observations can be used to assess spatially varying, near real time weights of different forecasts. The results showed that, although a MME based on multiple forecasts only may improve the forecast, if the forecasts are unbiased, it is essential to use observations in the MME approach so that proper weights from different models can be calculated and forecast bias can be corrected. It is also noted that, in some months, e.g., June in Baltic Sea, even SST was assimilated, the forecast still show quite high error. There are also visible difference between different Copernicus Marine Environment Monitoring Service (CMEMS) satellite products, e.g. OSTIA and regional SST products, which can lead different forecast quality if different SST observation products are assimilated.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2023, 17, 3; 533--541
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Verification of ships trajectory planning algorithms using real navigational data
Autorzy:
Lazarowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/117103.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Visibility Graph-search Algorithm (VGA)
Discrete Artificial Potential Field (DAPF)
real navigational data
ARPA
ship's trajectory planning
ship's trajectory planning algorithms
Ant Colony Optimization (ACO)
Trajectory Base Algorithm (TBA)
Opis:
The paper presents results of ship's safe trajectory planning algorithms verification. Real navigational data registered from a radar with an Automatic Radar Plotting Aid on board the research and training ship Horyzont II were used as input data to the algorithms. The algorithms verified in the presented research include the Ant Colony Optimization algorithm (ACO), the Trajectory Base Algorithm (TBA), the Visibility Graph-search Algorithm (VGA) ant the Discrete Artificial Potential Field algorithm (DAPF). Details concerning data registration and exemplary results obtained with the use or real navigational data are introduced and summarized in the paper. Presented results prove the applicability of proposed algorithms for solving the ship's safe trajectory planning problem.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 3; 559-564
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in and recent experiences from Norwegian Emergency Towing Service (NETS)
Autorzy:
Berg, T. E.
Selvik, Ø
Powiązania:
https://bibliotekanauki.pl/articles/1841548.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Search and Rescue
Viking Sky
Norwegian waters
Norwegian Emergency Towing Service
Norwegian Coastal Administration
Norwegian Coast Guard
Vessel Traffic Centre
Vessel Traffic Service
Opis:
The Norwegian Emergency Towing Services (NETS) is managed by the Norwegian Coastal Administration (NCA). In the early days of the NETS, the operational part was sheared between commercial tug companies and the Norwegian Coast Guard (NCG). A major change in the organization of the operation took place from January 1st 2020, when NCG was given the operational responsibility for NETS. This change is briefly described and the vessels in today's NETS are presented. Statistics for drifting vessels in Norwegian waters are presented before some selected recent maritime emergency incidents are highlighted. Actions by the NETS vessels and other NCG vessels will be highlighted. Handling of "FV Nortguider" after the grounding in Hinlopen (Svalbard) and the wreck removal work is one of the cases. The other two are drifting ship represented by the cruise vessel "Viking Sky" and the cargo vessel "Eemslift Hendrika". The final part of this paper discusses ways to ensure knowledge and operational experience sharing for personnel on vessels performing emergency towing tasks.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 1; 203-209
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 Lampedusa Disaster: How to Prevent Further Loss of Life at Sea?
Autorzy:
Coppens, J.
Powiązania:
https://bibliotekanauki.pl/articles/117543.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Safety Barriers
Lampedusa Disaster
Loss of Life at Sea
Safety of Life at Sea (SOLAS) Convention
Mediterranean Sea
Migrants, Place of Safety
search and rescue (SAR)
Opis:
Lampedusa – an Italian island barely 70 miles from northern Africa and 100 miles from Malta – has become a gateway to Europe for migrants. In some seasons, boats filled with asylum seekers arrive almost daily. However, yearly, hundreds of people die trying to cross the Mediterranean Sea. This paper will deal with the obligations of States towards seaborne migrants, the question of why so many people die near Lampedusa and the possible solutions in order to prevent further loss of life at sea.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2013, 7, 4; 589-598
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Developing generative adversarial nets to extend training sets and optimize diiscrete actions
Autorzy:
Zhang, R. L.
Furusho, M.
Powiązania:
https://bibliotekanauki.pl/articles/116509.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Maritime Education and Training (MET)
Generative Adversarial Network (GAN)
discrete actions
MET System in Japan
Lifeboat
Monte Carlo Tree Search (MCTS)
learning methods
unmanned ship navigation
Opis:
This study proposes the use of generative adversarial networks (GANs) to solve two crucial problems in the unmanned ship navigation: insufficient training data for neural networks and convergence of optimal actions under discrete conditions. To achieve smart collision avoidance of unmanned ships in various sea environments, first, this study proposes a collision avoidance decision model based on a deep reinforcement learning method. Then, it utilizes GANs to generate enough realistic image training sets to train the decision model. According to generative network learning, the conditional probability distribution of ship maneuvers is learnt (action units). Subsequently, the decision system can select a reasonable action to avoid the obstacles due to the discrete responses of the generated model to different actions and achieve the effect of intelligent collision avoidance. The experimental results showed that the generated target ship image set can be used as the training set of decision neural networks. Further, a theoretical reference to optimize the optimal convergence of discrete actions is provided.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 4; 875-880
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 Selection of Signals for Continuous Wave Radar which Reduce the Sensitivity to Doppler Shift of Frequencies
Autorzy:
Koshevyy, V.M.
Koshevyy, I.V.
Dolzhenko, D.O.
Powiązania:
https://bibliotekanauki.pl/articles/117565.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
sensitivity
search and rescue transponder (SART)
Doppler shift of frequiecies
microwave
selection of signals
continuous wave radar
radar equipment
Opis:
The signals with ideal correlation properties are of interest for continuous wave radar. At the same time it’s important to provide low sensitivity to Doppler shifts of frequencies. There were considered signals with special structure due to amplitude modulation which provide capability of radar work with Search and Rescue Transponder (SART). Because the amplitude modulation has a drawback – not efficient use of signal energy, in a class of proposed signals there were considered signals with uniform amplitude. The mismatched filtering may be used by means special weighting functions for obtaining the necessary correlation properties.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2016, 10, 1; 125-129
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł

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