Journal articles: 'Ship stability'

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Zou, Yin Cai, and Wei Gang Zheng. "The Structure Design of Parent-Subsidiary Wind Sailing Boat and the Matching Research of Power Plant." Advanced Materials Research 912-914 (April 2014): 1032–36. http://dx.doi.org/10.4028/www.scientific.net/amr.912-914.1032.

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Wind sailing boat fades out maritime transport industry gradually, because of its existence decreases the ship stability, and threatens mariners and ships security vastly. Project group has worked out high stability and security ship through researching literature and emulation-technique. Through the design of a parent ship and a sub-shipa set of wind sailing system and a water supply and drainage system, and the modeling calculation and analysis about the thrust of the fixed pitch propeller matching with the sailing, we can conclude that the added sub-ships can enhance ships stability in constant speed sailing situation. So it can improve thrust and reduce fuel consumption through increasing the scale of wind sailing.

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Yilmaz, Hüseyin, and Abdi Kükner. "An Approximate Method for Intact Stability of Fishing Vessels." Marine Technology and SNAME News 36, no. 03 (July 1, 1999): 171–74. http://dx.doi.org/10.5957/mt1.1999.36.3.171.

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It is well known that stability is the most important safety requirement for ships. One should have some information on ship stability at the preliminary design stage in order to reduce risk. Initial stability of ships is an important criterion and can be closely evaluated in terms of form parameters and vertical center of gravity. In this study, using some sample ship data, approximate formulations are derived by means of regression analysis for the calculations expressed in terms of ship preliminary design parameters that can easily provide approximate GM calculations. Thus designers can be provided with ship stability at the preliminary design stage, and also a set of appropriate design parameters for improving vessel stability can easily be determined.

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Mohan, Poonam, and A. P. Shashikala. "Stability Assessment of Drill Ship Using Probabilistic Damage Stability Analysis." Transactions on Maritime Science 8, no. 2 (October 21, 2019): 180–97. http://dx.doi.org/10.7225/toms.v08.n02.003.

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Drill ship is a ship-shaped structure with a drilling unit at its center and with oil compartments, which is moored and kept in position using anchors. These ships should be capable of working in deep sea for a long time, hence affected by harsh ocean environment. Drill units are said to have greater heave motion, and the height of the derrick influences the vessel’s stability. MARPOL Oil Outflow Analysis is performed for damaged crude oil carriers or tankers and Mobile offshore drilling units (MODU) in damaged condition. In the present study, probabilistic analysis is performed on drill ship to understand its stability behavior under damaged condition. Stability assessments are carried out by considering single and multiple damage locations. Oil outflow analysis is carried out for different damage cases of oil tank. Probabilistic damage assessment is done for load cases up to 50% flooding, to obtain stability charts. These charts will be useful to understand variations in stability parameters under damaged conditions.

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Bačkalov, I., S. Rudaković, and M. Cvijović. "Intact Stability of Historic Passenger Ships in Light of the Second Generation Intact Stability Criteria." International Journal of Maritime Engineering 163, A1 (April 7, 2021): 119–30. http://dx.doi.org/10.5750/ijme.v163ia1.10.

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The paper examines the intact stability of historic passenger ships from the point of view of the contemporary notion of the intact stability, i.e. the Second Generation Intact Stability Criteria (SGISC) framework. An intact stability assessment using the Vulnerability Level 2 calculation procedures of SGISC for the dead ship condition was performed on four ocean liners: RMS Titanic, RMS Queen Mary, SS United States and SS Michelangelo, and two cruise ships: MS Song of America and MS Costa Concordia. In addition, the intact stability of the selected ships was appraised using the present-day mandatory intact stability requirements contained in the 2008 Intact Stability Code. The selected ships are believed to be good representatives of the main trends in passenger ship design over a one-hundred-year span bounded by two well-known maritime catastrophes: the sinking of the Titanic in 1912 and the Costa Concordia disaster in 2012. The paper offers an insight into how major design changes have affected the intact stability properties of passenger ships over this period. It was found that the examined ocean liners would perform well in terms of intact stability in the dead ship condition even from the point of view of the SGISC. The analysis also confirmed the advantages of the approach using the SGISC framework over simplified, (semi)empirical stability assessment methods. By looking into the evolution of the intact stability of ocean liners and cruise ships from the contemporary perspective, the paper draws the conclusions which are considered useful for the design of future passenger ships.

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Mégel, Jacques, and Janis Kliava. "Metacenter and ship stability." American Journal of Physics 78, no. 7 (July 2010): 738–47. http://dx.doi.org/10.1119/1.3285975.

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Woo, Donghan, Hun Choe, and Nam-Kyun Im. "Analysis of the Relationship between GM and IMO Intact Stability Parameters to Propose Simple Evaluation Methodology." Journal of Marine Science and Engineering 9, no. 7 (July 2, 2021): 735. http://dx.doi.org/10.3390/jmse9070735.

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Securing a ship’s safe stability is essential. Thus, monitoring the stability parameters of the IMO requirements is required to provide an alert about the risk of the safety of ships’ stability to the captain, officers, and the crew of a ship. However, calculating all ships’ intact stability parameters is complex without ship loading software or equipment. To evaluate ships’ intact stability parameters, a convenient methodology to simply calculate them is necessary as a supplementary method for ships in the absence of loading software or equipment. In the present study, the Simple Evaluation Methodology for Intact Stability (SEMIS) is proposed. SEMIS is introduced for simply evaluating the safety of ships’ stability according to GM. Based on the stability parameters of 336 loading conditions of 19 model ships, empirical formulas of SEMIS are derived. To verify the proposed methodology, the stability parameters of two model ships in 28 loading conditions are calculated using the proposed empirical formulas and the principal calculation methods, respectively, and then compared. The developed SEMIS efficiently evaluates the ships’ stability using only GM.

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Hu, Lifen, Chen Yao, Wubin Li, Xiangyang Wang, and Zhongyu Sun. "Capsizing Performance of Dead Ship Stability for Damaged Ships." Marine Technology Society Journal 55, no. 1 (January 1, 2021): 115–26. http://dx.doi.org/10.4031/mtsj.55.1.10.

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AbstractThis study proposes a method for combining capsizing probability and flooding process to investigate the time-domain dead ship stability of a damaged ship. It focuses on a nonlinear righting lever GZ curve solution in the following aspects: one aspect subjects the influence of damaged tanks on a hull shape to the wind and wave, and the other aspect is based on a real-time calculation of the GZ curve. According to 1‐degree-of-freedom rolling equation, the damaged capsizing probability model is established through fourth-order Runge-Kutta algorithm and Monte Carlo simulation. Also, the model solution is applied on the basis of Visual Basic 6.0 language, and the results are compared with the NAPA platform. The most significant development in this study is combining time-domain flooding process and capsizing probability calculation. To verify the proposed methods, two damaged fishery bureau vessels are used as the sample ships. Results of time-domain capsizing probability under different loading conditions are compared, and the difference and its possible reasons are analyzed.

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Yao, Qi Guo, and Yu Liang Liu. "Simulation and Analysis of Dynamic Characteristics of Rolling Motion of Rotational Molding Ship." Applied Mechanics and Materials 556-562 (May 2014): 1278–81. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.1278.

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Parametric resonance can lead to roll motions and endanger the ship, cargo and crew. The QR-factorization method for calculating lyapunov characteristic exponents (LCEs) was introduced. And then, parametric resonance stability of ships in longitudinal waves was analyzed by taking the fishing-entertainment rotational molding boat as an example. Simulation results show that, this method can be used to analyze ship stability and to accurately identify safe and unsafe operating conditions for a ship in longitudinal waves.

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Nabawi, Rahmat Azis, Syahril Syahril, and Salmat Salmat. "Stability Study of Flat Hull Ship for Fishing Tourism." Teknomekanik 3, no. 2 (December 10, 2020): 80–85. http://dx.doi.org/10.24036/teknomekanik.v3i2.9272.

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The availability of boats is needed to develop fishing tourism. Most of the boats used so far generally use fishing boats made of woodcut in the forest, so this can damage the environment and cause natural disasters. Ships using a flat plate hull made of steel can be a substitute for wooden ships. This study aims to test the stability of a flat plate vessel designed for fishing boats. The ship stability test was carried out using a computer simulation method using Maxsurf Stability software. The ship stability criteria refer to the International Maritime Organization code A.749 (18), Ch 3-design criteria applicable to all ships. The ship stability analysis was carried out on two variations of the load case. The value of GZ at A h 300, A h 400 and A h 300 - A h 400 for load case 1 and 2 are greater than the minimum standards determined by IMO. The maximum GZ value at load case 1 occurs at an angle of 400 and at load case 2 at an angle of 60.90. The GM value in load case 1 is 0.609 meters and in load case 2 is 0.485 meters. Based on the results of the tests that have been carried out, it can be denied that the flatboat design model for fishing tourism meets the criteria set by the International Maritime Organization.

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Wang, Peng, and Ding Bu. "The Optimization Design for Ship Lock Structure." Journal of Computational and Theoretical Nanoscience 13, no. 10 (October 1, 2016): 7257–61. http://dx.doi.org/10.1166/jctn.2016.5703.

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Ship lock is one of the main methods for navigation. It usually guarantees ships go through the lock safely. Therefore, the proper design of ship lock is extraordinarily significant. This paper will set one ship lock project as an example, and discuss the ship lock structure by Abaqus finite element analysis. And then, it will discuss the key factors which affect ship lock’s safety and stability. Finally, optimization design for ship lock structure will be provided.

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Panasiuk, Irina, Sergejus Lebedevas, and Jonas Čerka. "The assessment algorithm of technological feasibility of SOx scrubber installation." Transport 33, no. 1 (March 29, 2016): 197–207. http://dx.doi.org/10.3846/16484142.2016.1152298.

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The problematics of installation of sulphur oxides (SOx) scrubber becomes much relevant for today due to the new Annex VI of MARPOL 73/78 requirements, which sets 0.1% SOx limits by 2015 in Emission Control Area (ECA) and globally to 0.5% in 2020. The research in this field becomes more significant for ship-owners. SOx scrubber is most promising alternative because of lower operating costs and suitability to existing ships. Despite the fact that exhausts gas scrubbing is a common and proven technology on land, the conditions on ships differ significantly and still there are not enough practical knowledge of installation of mentioned equipment. In addition, speaking about existing ships there are some limitation factors of SOx scrubber installation on-board, which will be discussed in the paper. Taking into account the size and mass of the SOx scrubber, it can be assumed that the recalculation of ship stability will be required for most ships. Therefore, the most important task for equipment designers is selection of scrubber system location with the minimum impact on ship stability and identification of necessary changes (deadweight, additional space, etc.) in accordance with ship safety requirements. For this reason, the research was carried-out in order to create the algorithm of ship stability assessment and selection of optimal scrubber location on-board.

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Gulyaev, Ilya A. Gulyaev, and Evgeniy P. Ronnov. "Сombined ships stability analysis at the stage of design study." Russian Journal of Water Transport, no. 66 (March 23, 2021): 29–35. http://dx.doi.org/10.37890/jwt.vi66.158.

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. A method of stability analysis for combined ship (oil carrier/platform ship type) at the stage of design study is presented. It should be noted that not all of ship’s main seaworthiness and operational characteristics are the result of a simple addition of the characteristics of an oil carrier and a platform ship. Their mutual influence takes place, which should be taken into account when analysing the stability in the multivariant optimization problems of internal and external design of such ships. This leads to the requirement to adjust the known methods of stability analysis at the initial stages of ship design, which was the purpose of the present work and its originality. Taking into account the multivariance of the task and the hull design type, the stability assessment will be carried out through the analysis of the metacentric height extreme value on the assumption that the requirements of Russian River Register for admissible heeling angle at static wind effect are met. In order to account for nonlinearity of static stability curve when inclining up to the angles of deck immersion into water and emergence of bilge, it is suggested to apply an approximate method of metacentric radius determination. The proposed method of combined ship stability assessment is recommended to apply at the stage of justification and analysis of ship’s key elements as a limitation in the problems of mathematical modeling of optimization of such type of ships. The method allows to exclude from further consideration at the design study stage the possible options that do not meet the requirements of seaworthiness.

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Mauro, Francesco, Luca Braidotti, and Giorgio Trincas. "A Model for Intact and Damage Stability Evaluation of CNG Ships during the Concept Design Stage." Journal of Marine Science and Engineering 7, no. 12 (December 8, 2019): 450. http://dx.doi.org/10.3390/jmse7120450.

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To face the design of a new ship concept, the evaluation of multiple feasible solutions concerning several aspects of naval architecture and marine engineering is necessary. Compressed natural gas technologies are in continuous development; therefore, there are no available databases for existing ships to use as a basis for the design process of a new unit. In this sense, the adoption of a modern multi-attribute decision-based method can help the designer for the study of a completely new ship prototype. A database of compressed natural gas ships was generated starting from a baseline hull, varying six hull-form parameters by means of the design of experiment technique. Between the attributes involved in the concept design process, stability is for sure one of the most relevant topics, both for intact and damaged cases. This work describes two approaches to identify the compliance of a ship with the intact stability regulations based on the ship main geometrical quantities. Moreover, a metamodel based on the maximum floodable length concept (damage stability) allows determining the main internal subdivision of the ship. The metamodel outcomes were compared with results from direct calculations on a ship external to the database, highlighting the adequate accuracy given by the developed methods.

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Malisan, Johny. "Tinjauan Kelaiklautan Kapal Tradisional Yang Beroperasi Di Wilayah Jakarta • Kepulauan Seribu." Warta Penelitian Perhubungan 24, no. 1 (May 9, 2019): 100. http://dx.doi.org/10.25104/warlit.v24i1.987.

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ABSmACTNumber of wooden-ships (people called them as kapal ojek) operated in 2011 are 34 vessels or equal to 1,199 gross tonnage and total capacity of 1,833 passengers. Since many accidents of ships occurs and to be public concern, the author is interested to make research in order to evaluate sea worthiness of their stability and users' opinion. 17tere are 5 aspect of opinions to be collected among others safety equipments, timeliness and ships availability, security and comfort, crews competencies, and tariff. Users' opinion is analyzed by using the Importance performance Index and Customer Satisfaction Index The results shows that many variables are still needed to improve tlmt could enhance the service performance of those ships. 17teir stabilities are relatively in good condition, but should always consider to loading and weather conditions because the ships are made of woods and low of freeboards.Keywords : ship safety, ship seaworthiness, ship stability

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15

Vassalos, Dracos, and M. P. Mujeeb-Ahmed. "Conception and Evolution of the Probabilistic Methods for Ship Damage Stability and Flooding Risk Assessment." Journal of Marine Science and Engineering 9, no. 6 (June 16, 2021): 667. http://dx.doi.org/10.3390/jmse9060667.

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The paper provides a full description and explanation of the probabilistic method for ship damage stability assessment from its conception to date with focus on the probability of survival (s-factor), explaining pertinent assumptions and limitations and describing its evolution for specific application to passenger ships, using contemporary numerical and experimental tools and data. It also provides comparisons in results between statistical and direct approaches and makes recommendations on how these can be reconciled with better understanding of the implicit assumptions in the approach for use in ship design and operation. Evolution over the latter years to support pertinent regulatory developments relating to flooding risk (safety level) assessment as well as research in this direction with a focus on passenger ships, have created a new focus that combines all flooding hazards (collision, bottom and side groundings) to assess potential loss of life as a means of guiding further research and developments on damage stability for this ship type. The paper concludes by providing recommendations on the way forward for ship damage stability and flooding risk assessment.

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Fang, Ming-Chung, and Jiun-Han Ju. "The Dynamic Simulations of the Ship Towing System in Random Waves." Marine Technology and SNAME News 46, no. 02 (April 1, 2009): 107–15. http://dx.doi.org/10.5957/mtsn.2009.46.2.107.

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In order to investigate the dynamic stability and safety for a ship towing system operated in waves, the present paper develops a nonlinear mathematical model, including seakeeping and maneuvering characteristics, to simulate dynamic behaviors of the towing system in random waves. In addition to waves, wind is also included in the calculations. The time history simulations of six degrees of freedom motion for both the towing and the towed ships are solved by the fourth-order Runge-Kutta method. Because of the waves, the dynamic properties including the towline tension, ship speeds, headings, and distance between two ships are different from those that occur in calm water. The effects of the towpoint's position, towline length, and towing speed on the ship course stability and towline tension are analyzed with respect to different wave and wind headings. In the present study, the suitable operation conditions for the ship towing system are investigated and can be suggested as a reference for improving the stability and safety of towing operation tasks at sea.

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Jovanoski, Z., and G. Robinson. "Ship Stability and Parametric Rolling." Australasian Journal of Engineering Education 15, no. 2 (January 2009): 43–50. http://dx.doi.org/10.1080/22054952.2009.11464028.

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Cleary, Chris, John C. Daidola, and Christopher J. Reyling. "Sailing Ship Intact Stability Criteria." Marine Technology and SNAME News 33, no. 03 (July 1, 1996): 218–32. http://dx.doi.org/10.5957/mt1.1996.33.3.218.

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The comeback in recent years to the world's oceans of large displacement sailing vessels has increased the interest in design requirements. At the same time, there have been a number of accidents and capsizings of sailing vessels that investigators have attributed to a lack of adequate intact stability. In an attempt to identify improved stability criteria for large sailing vessels, using the U.S. Coast Guard training barque Eagle as a model, the authors have conducted a worldwide search of the literature and other sources to gather a body of criteria for comparison with each other and then with the existing standards for the Eagle. The results of this research are presented and illustrated, including the domain of interaction between ship motion and sail forces. The methods presented herein could be a useful contribution to the safe design and operation of large sailing vessels.

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Hetharia, Wolter R. "Preliminary Study on Stability Parameters of Semi-Displacement Ships." Applied Mechanics and Materials 874 (January 2018): 105–13. http://dx.doi.org/10.4028/www.scientific.net/amm.874.105.

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Semi-displacement passenger ships operate at the speed range of 19 to 23 knots or Froude number Fn of 0.50 to 0.75. Those ships need higher engine power to maintain their speeds. The efforts should be made to minimize their higher engine powers. Most experts worked to minimize the engine power for most merchant ships. In their works, the initial metacentric (GMO) at departure condition was taken as constraint to represent stability parameters. However, this is not a general case for semi-displacement passenger ships. In this study, a parent semi-displacement passenger was designed and modified. Stability parameters were computed and evaluated as required by the rules IMO-HSC. In addition, one existing high speed passenger ship was evaluated for stability evaluation as reference also. It was found that the stability parameters at large angles of inclination such as: weather criterion, angle of GZmaxand others are more critical compared to GM0. Also, the stability parameters when ship is at arrival condition are more critical compared to those at departure condition. The study resumed that the application of criterion GM0≥ 0.15 m at optimization process of semi-displacement passenger ships should be considered again for the future.

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Nekrasov, Valeriy. "Mean-Square Non-Local Stability of Ship in Storm Conditions of Operation." Polish Maritime Research 26, no. 4 (December 1, 2019): 6–15. http://dx.doi.org/10.2478/pomr-2019-0061.

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Abstract The purpose of the paper is to create a method for studying nonlocal stability in the mean and in the mean square of the ship, positioned on the beam of an intensive wind–waves mode, which is based on the use of the correlation theory of random functions close to continuous Markov processes. With the help of this method and the integral formula of event probability, a method for determining the reliability indicator of the ship in respect of the existing wind–waves excitations of the operating area is formed. An example of investigating the nonlinear motion of the ship, determining its local and nonlocal stability in the first approximation of the theory of considered random functions, is given. Such approximation uses correlation theory with models of acting excitations represented by the generalised derivatives of the Wiener process. Moreover, special attention is paid to reflecting the connection of the proposed methods for investigating the ship stability under constantly acting random excitations with the traditional methods of studying ship stability at small and large inclinations. The established connection defines the proposed methods as a development of the traditional methods of ship stability deterministic theory during the transition to its formation in the class of random functions, with the addition to these methods of the missing link of determining the level of reliability of ships towards the acting wind–waves excitations of the operation area.

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Cheng, Peng, Ning Liang, Ruiye Li, Hai Lan, and Qian Cheng. "Analysis of Influence of Ship Roll on Ship Power System with Renewable Energy." Energies 13, no. 1 (December 18, 2019): 1. http://dx.doi.org/10.3390/en13010001.

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Renewable energy ship was regarded as one of the ship energy technologies with a good prospect. In order to study the application of solar and wind energy on ships in the marine environment and the impact of ship rolling on the system, the feasibility of applying solar energy and wind energy to ships was analyzed, and the structural composition of ship power system incorporating renewable energy source was studied. The model of the ship power system integrated with renewable energy was built in PSCAD/EMTDC simulation software. The layout of wind power generation system and photovoltaic power generation system was given for the actual ship, and the ship parameters and specific parameters of each simulation module were determined. It can be seen that the rolling of ship will cause fluctuations in the grid-connected power of the photovoltaic power generation system and the wind power generation system from the comparison of the simulation curves. Finally, a simulation experiment is provided to prove the access of the battery can well suppress the grid-connected power fluctuation caused by the rolling of the ship, which has an important impact on the stability of the ship power system with renewable energy.

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Bernitsas, M. M., and N. S. Kekridis. "Simulation and stability of ship towing." International Shipbuilding Progress 32, no. 369 (May 1, 1985): 112–23. http://dx.doi.org/10.3233/isp-1985-3236901.

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Cherevko, E., and N. Vasilchenko. "Worn Condition Ship Set Stability Estimation." IOP Conference Series: Earth and Environmental Science 272, no. 3 (June 22, 2019): 032249. http://dx.doi.org/10.1088/1755-1315/272/3/032249.

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ALLIEVI, A., and A. SOUDACK. "Ship stability via the Mathieu equation." International Journal of Control 51, no. 1 (January 1990): 139–67. http://dx.doi.org/10.1080/00207179008934054.

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Francescutto, Alberto. "Intact Ship Stability: The Way Ahead." Marine Technology and SNAME News 41, no. 01 (January 1, 2004): 31–37. http://dx.doi.org/10.5957/mt1.2004.41.1.31.

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This paper, prepared as an introduction to the Session on Stability Standards: the Way Ahead, contains some notes and considerations of the author following the discussion of the item Revision of the Intact Stability Code at the recent meetings of the International Maritime Organization Subcommittee on Stability and Load Lines and Fishing Vessels Stability held in London in July 2002 and in September 2003.

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Petacco, Nicola, and Paola Gualeni. "IMO Second Generation Intact Stability Criteria: General Overview and Focus on Operational Measures." Journal of Marine Science and Engineering 8, no. 7 (July 5, 2020): 494. http://dx.doi.org/10.3390/jmse8070494.

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At the beginning of 2020, after a long and demanding process, the Second Generation Intact Stability criteria (SGISc) have been finalized at the 7th session of the International Maritime Organization (IMO) sub-committee on Ship Design and Construction (SDC). At present, SGISc are not mandatory, nevertheless IMO endorses their application in order to assess their consistency and validity. It is envisaged that SGISc can support the design of safer ships, nevertheless such a rules framework might have an impact also on the ship operational aspects in a seaway. In fact, within the SGISc framework, Operational Measures have also been implemented providing guidance and limitations during navigation. After a comprehensive overview about SGISc vulnerability levels and direct stability assessment, this paper provides a specific insight into the methodological approach for the Operational Measures extensively addressed as a complementary action to ship design.

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Zăgan, Remus, and Gabriel Raicu. "Understanding the OT cyber risk on board ship and ship stability." Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XI, Construcţii navale/ Annals of "Dunărea de Jos" of Galati, Fascicle XI, Shipbuilding 42 (November 26, 2019): 81–90. http://dx.doi.org/10.35219/annugalshipbuilding.2019.42.11.

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Kim, Dong-Gyun, Katsutoshi Hirayama, and Gyei-Kark Park. "Collision Avoidance in Multiple-Ship Situations by Distributed Local Search." Journal of Advanced Computational Intelligence and Intelligent Informatics 18, no. 5 (September 20, 2014): 839–48. http://dx.doi.org/10.20965/jaciii.2014.p0839.

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As vital transportation carriers in trade, ships have the advantage of stability, economy, and bulk capacity over airplanes, trucks, and trains. Even so, their loss and cost due to collisions and other accidents exceed those of any other mode of transportation. To prevent ship collisions many ways have been suggested, e.g., the 1972 COLREGs which is the regulation for preventing collision between ships. Technologically speaking, many related studies have been conducted. The term “Ship domain” involves that area surrounding a ship that the navigator wants to keep other ships clear of. Ship domain alone is not sufficient, however, for enabling one or more ships to simultaneously determine the collision risk for all of the ships concerned. Fuzzy theory is useful in helping ships avoid collision in that fuzzy theory may define whether collision risk is based on distance to closest point of approach, time to closest point of approach, or relative bearing – algorithms that are difficult to apply to more than one ships at one time. The main purpose of this study is thus to reduce collision risk among multiple ships using a distributed local search algorithm (DLSA). By exchanging information on, for example, next-intended courses within a certain area among ships, ships having the maximum reduction in collision risk change courses simultaneously until all ships approach a destination without collision. In this paper, we introduce distributed local search and explain how it works using examples. We conducted experiments to test distributed local search performance for certain instances of ship collision avoidance. Experiments results showed that in most cases, our proposal applies well in ship collision avoidance amongmultiple ships.

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Zheng, Jian, Ming Yan, Yun Li, Changhai Huang, Yiping Ma, and Fei Meng. "An online identification approach for a nonlinear ship motion model based on a receding horizon." Transactions of the Institute of Measurement and Control 43, no. 13 (July 20, 2021): 3000–3012. http://dx.doi.org/10.1177/01423312211019654.

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The ship motion system is a nonlinear control object, and its system parameters exhibit time-varying characteristics with the ship motion state, which increases the difficulty of control. Therefore, parameter identification has an important significance for the stability of ship motion control. Aiming at the real-time identification problem of the nonlinear and time-varying ship motion system during movement, this paper reconstructs the ship motion system with the propeller speed and rudder angle as control variables and designs an online identification algorithm with the sliding time window method based on the extended Kalman filter algorithm. In addition, to solve the problem of noise in ship motion data collected in real-time, a real-time wavelet filter is developed to perform online preprocessing of the input data of the identification algorithm. The applicability of the method is further demonstrated via a model-scale Korea Research Institute of Ships and Ocean Engineering container ship free-running experiments in a basin.

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Vassalos, Dracos, and Donald Paterson. "Reconfiguring Passenger Ship Internal Environment for Damage Stability Enhancement." Journal of Marine Science and Engineering 8, no. 9 (September 7, 2020): 693. http://dx.doi.org/10.3390/jmse8090693.

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The traditional risk control option adopted in naval architecture to meet safety-related objectives is by regulations, targeting damage limitation, nominally instigated in the wake of maritime accidents claiming heavy loss of life. These primarily concern the introduction of watertight bulkheads, i.e., permanent (passive) reconfiguration of the internal ship environment to enhance damage stability. This has been the most common measure, manifesting itself in the wake of every serious flooding accident since the beginning, back in the 19th century. However, traditional flooding protection through watertight subdivision, to an extent dictated by IMO regulations, has a physical limit which, if exceeded, a safety plateau is reached. This is currently the case and with damage stability standards progressively increasing, the safety gap between existing and new ships is dangerously widening and with design stability margins progressively eroding, stability management is unsustainable, leading to loss of earnings at best. The need for managing the residual risk through active intervention/protection over the life-cycle of the vessel drives industry to searching and adopting a new normal. This new normal is the innovation being explained in this paper by addressing safety enchantment through a systematic reconfiguration of the ship environment for passive and active protection in flooding accidents. In this respect, the “design-optimal” internal arrangement of a vessel, is adapted and reconfigured, using passive and active containment systems for flooding incidents, in the form of high-expansion foam products. The innovation is briefly explained, claiming transformational reduction in flooding risk in the most cost-effective way available. To support wider understanding and appreciation for the latter, the paper critically reviews the whole evolution of internal ship space reconfiguration, chronologically and systematically, concluding that new technological developments and breakthroughs will bring sustainable changes to the traditional evolutionary maritime safety enhancement.

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Acanfora, Maria, and Antonio Cirillo. "A simulation model for ship response in flooding scenario." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 231, no. 1 (August 3, 2016): 153–64. http://dx.doi.org/10.1177/1475090215627839.

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Recent ship damages underline the importance of an accurate intact and damage stability analysis. The stability of ships is presently determined by applying quasi-static methods, neglecting dynamic effects; for flooding scenarios, flow calculations are not carried out either. In general, for damage cases, water dynamics inside the compartment affect ship motions. It has been observed that some kind of vessels could experience large roll motions due to the sudden water ingress after damage. In this article, a non-linear tool for damage stability evaluation is presented, including water dynamics in a flooded compartment. In particular the transient stage of flooding is investigated. The flooded water has been treated using the lumped mass approach. A new method has been developed and applied in this article in order to model the water motions: the freesurface is assumed to be no more horizontal but dependent on ship and flooded water accelerations. The developed method is intended to be an intermediate approach between the quasi-static method (uncoupled) and fully coupled method. In coupling the flooded water motions with ship motions, no more unknowns are introduced: only ship lateral acceleration is used to determine the freesurface inclination of the flooded water. A valuation is carried out, comparing the numerical result from the simulations with the experimental studies on a barge model. Additional applications are carried out on the free roll motion of the TNK tanker model.

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Isnardi, Isabelle, Renaud Lesourne, Pierre Bruhns, Wolf H. Fridman, John C. Cambier, and Marc Daëron. "Two Distinct Tyrosine-based Motifs Enable the Inhibitory Receptor FcγRIIB to Cooperatively Recruit the Inositol Phosphatases SHIP1/2 and the Adapters Grb2/Grap." Journal of Biological Chemistry 279, no. 50 (September 28, 2004): 51931–38. http://dx.doi.org/10.1074/jbc.m410261200.

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FcγRIIB are low-affinity receptors for IgG that contain an immunoreceptor tyrosine-based inhibition motif (ITIM) and inhibit immunoreceptor tyrosine-based activation motif (ITAM)-dependent cell activation. When coaggregated with ITAM-bearing receptors, FcγRIIB become tyrosyl-phosphorylated and recruit the Src homology 2 (SH2) domain-containing inositol 5′-phosphatases SHIP1 and SHIP2, which mediate inhibition. The FcγRIIB ITIM was proposed to be necessary and sufficient for recruiting SHIP1/2. We show here that a second tyrosine-containing motif in the intracytoplasmic domain of FcγRIIB is required for SHIP1/2 to be coprecipitated with the receptor. This motif functions as a docking site for the SH2 domain-containing adapters Grb2 and Grap. These adapters interact via their C-terminal SH3 domain with SHIP1/2 to form a stable receptor-phosphatase-adapter trimolecular complex. Both Grb2 and Grap are required for an optimal coprecipitation of SHIP with FcγRIIB, but one adapter is sufficient for the phosphatase to coprecipitate in a detectable manner with the receptors. In addition to facilitating the recruitment of SHIPs, the second tyrosine-based motif may confer upon FcγRIIB the properties of scaffold proteins capable of altering the composition and stability of the signaling complexes generated following receptor engagement.

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Liu, Yong, Renxiang Bu, and Xiaori Gao. "Ship Trajectory Tracking Control System Design Based on Sliding Mode Control Algorithm." Polish Maritime Research 25, no. 3 (September 1, 2018): 26–34. http://dx.doi.org/10.2478/pomr-2018-0093.

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Abstract The paper reports the design and tests of the planar autopilot navigation system in the three-degree-of-freedom (3-DOF) plane (surge, sway and yaw) for a ship. The aim of the tests was to check the improved maneuverability of the ship in open waters using the improved nonlinear control algorithm, developed based on the sliding mode control theory for the ship-trajectory tracking problem of under-actuated ships with static constraints, actuator saturation, and parametric uncertainties. With the integration of the simple increment feedback control law, the dynamic control strategy was developed to fulfill the under-actuated tracking and stabilization objectives. In addition, the LOS (line of sight) guidance system was applied to control the motion path, whereas the sliding mode controller was used to emulate the rudder angle and propeller rotational speed control. Firstly, simulation tests were performed to verify the validity of the basic model and the tracking control algorithm. Subsequently, full scale maneuverability tests were done with a novel container ship, equipped with trajectory tracking control and sliding mode controller algorithm, to check the dynamic stability performance of the ship. The results of the theoretical and numerical simulation on a training ship verify the invariability and excellent robustness of the proposed controller, which: effectively eliminates system chattering, solves the problem of lateral drift of the ship, and maintains the following of the trajectory while simultaneously achieving global stability and robustness.

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Özkan, İ. R. "Applications of the ship practical stability criteria1." International Shipbuilding Progress 32, no. 374 (October 1, 1985): 226–43. http://dx.doi.org/10.3233/isp-1985-3237401.

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35

Ferreiro Garcia, R., C. Antonio, and F. Ameal. "Ship Stability Monitoring by Motion Frequency Analysis." IFAC Proceedings Volumes 34, no. 7 (July 2001): 39–43. http://dx.doi.org/10.1016/s1474-6670(17)35056-5.

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Fitriadhy, Ahmad, and Hironori Yasukawa. "Course Stability of a Ship Towing System." Ship Technology Research 58, no. 1 (January 2011): 4–23. http://dx.doi.org/10.1179/str.2011.58.1.001.

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37

Niţă, Cristian-Milică. "Ballast tanks sizing and ship stability analysis." IOP Conference Series: Earth and Environmental Science 635 (January 13, 2021): 012005. http://dx.doi.org/10.1088/1755-1315/635/1/012005.

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YANG, XIUFENG, SHILIU PENG, MOUBIN LIU, and JIARU SHAO. "NUMERICAL SIMULATION OF BALLAST WATER BY SPH METHOD." International Journal of Computational Methods 09, no. 01 (March 2012): 1240002. http://dx.doi.org/10.1142/s0219876212400026.

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Ballast water has frequently been used in ships to provide stability and adjust trim, stress, and torsion for optimal steering and propulsion. Numerical simulation of the movement of ballast water and its interaction with the solid walls of operating ships are very difficult for traditional grid-based numerical models. In this paper, the smoothed particle hydrodynamics (SPH) method is applied to simulate water tank sloshing and the movement of ships carrying ballast water in three cases. Numerical results of water tank sloshing are compared with experimental ones. Numerical results of ships indicate that carrying ballast water in several separated small tanks generally makes a ship more stable, but keeping ballast water in one big tank generally makes a ship more unstable.

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Umeda, Naoya, Tomoko Kamo, and Yoshiho Ikeda. "Some Remarks on Theoretical Modeling of Damaged Stability." Marine Technology and SNAME News 41, no. 01 (January 1, 2004): 45–49. http://dx.doi.org/10.5957/mt1.2004.41.1.45.

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The authors raise several points for discussion to develop theoretical modeling of damaged stability in waves. First, hydrodynamic modeling of behaviors of a damaged ship in waves is discussed in the light of multiple time scale expansion. This provides a theoretical background to calculate hydrodynamic forces acting on a hull with sinkage and heel due to water accumulation inside the hull taken into account. Second, the reason why the International Towing Tank Conference (ITTC) benchmarktesting for a damaged ship resulted in insufficient prediction of roll motions is discussed based on results of model experiments with a flooded compartment model. Third, survivability of a damaged ship with multiple decks in a damaged compartment is discussed in the light of model experiments on flooding of a pure car carrier (PCC) in calm water and waves. The experimental study shows that survivability of such a ship is different from that obtained in a static assumption even in calm water, and its dynamic behaviors in waves significantly depend on initial state and transient process of flooding. If so, the model test method used in the Stockholm Agreement can be inappropriate for this type of ship.

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IM, Nam-Kyun, and Hun CHOE. "A quantitative methodology for evaluating the ship stability using the index for marine ship intact stability assessment model." International Journal of Naval Architecture and Ocean Engineering 13 (2021): 246–59. http://dx.doi.org/10.1016/j.ijnaoe.2021.01.005.

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Li, Ronghui, Tieshan Li, Renxiang Bu, Qinling Zheng, and C. L. Philip Chen. "Active Disturbance Rejection with Sliding Mode Control Based Course and Path Following for Underactuated Ships." Mathematical Problems in Engineering 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/743716.

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The compound control of active-disturbance-rejection control (ADRC) with sliding mode is proposed to improve the performance of the closed-loop system and deal with the constraint condition problem of a surface ship. The advantages of ADRC with sliding mode were verified by ship course control simulations. Meanwhile, to solve the path-following problem of underactuated surface ships with uncertainties of internal dynamic and external disturbances, the ADRC controller with sliding mode is introduced to steer the ship to follow the desired path. In order to overcome the cross-track error caused by wind and current, drift angle is compensated in the controller by designing a coordinate transformation equation. Simulations were performed on a nonlinear kinematics model of a training ship to validate the stability and excellent robustness of the proposed path-following controller.

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Hu, Li-fen, Hao Wu, Qingtao Gong, Xiangyang Wang, and Wenbin Lv. "Time-Domain Flooding Simulation of a Damaged Warship." Marine Technology Society Journal 54, no. 2 (March 1, 2020): 69–78. http://dx.doi.org/10.4031/mtsj.54.2.7.

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AbstractUnderstanding of the complex dynamic behavior of damaged ships and floodwater remains limited for ship designers and safety authorities. In this work, a Navier-Stokes (NS) solver that combines the volume of fluid (VOF) method with overset mesh techniques is developed to simulate the flooding process of a damaged ship. The VOF method captures the fluid interface, and the turbulence effect on flows is considered with the k-ω model. The overset mesh techniques are employed to handle the mesh update following transient ship motions. Then, the results of a damaged barge with dynamic and overset mesh are compared with the experimental data. On the basis of this validation, the solver is applied to the flooding problems of a damaged warship. This research is intended to be a useful step toward the establishment of a stability criterion for damaged ships in the future.

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Song, C. H., H. S. Kim, R. von Glasow, P. Brimblecombe, J. Kim, R. J. Park, and J. H. Woo. "Source identification and budget analysis on elevated levels of formaldehyde within ship plumes: a photochemical/dynamic model analysis." Atmospheric Chemistry and Physics Discussions 10, no. 6 (June 23, 2010): 15441–83. http://dx.doi.org/10.5194/acpd-10-15441-2010.

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Abstract. Elevated levels of formaldehyde (HCHO) along the ship corridors have been observed by satellite sensors, such as ESA/ERS-2 GOME (Global Ozone Monitoring Experiment), and were also predicted by global 3-D chemistry-transport models. In this study, three likely sources of the elevated HCHO levels were investigated to identify the detailed sources and examine the contributions of the sources (budget) of the elevated levels of HCHO in the ship corridors using a newly-developed ship-plume photochemical/dynamic model: (1) primary HCHO emission from ships; (2) secondary HCHO production via the atmospheric oxidation of Non-methane volatile organic compounds (NMVOCs) emitted from ships; and (3) atmospheric oxidation of CH4 within the ship plumes. From multiple ship-plume model simulations, CH4 oxidation by elevated levels of in-plume OH radicals was found to be the main factor responsible for the elevated levels of HCHO in the ship corridors. More than ~91% of the HCHO for the base ship plume case (ITCT 2K2 ship-plume case) is produced by this atmospheric chemical process, except in the areas close to the ship stacks where the main source of the elevated HCHO levels would be primary HCHO from the ships (due to the deactivation of CH4 oxidation from the depletion of in-plume OH radicals). Because of active CH4 oxidation (chemical destruction of CH4) by OH radicals, the instantaneous chemical lifetime of CH4 (τ CH4) decreased to ~0.45 yr inside the ship plume, which is in contrast to τ CH4 of ~1.1 yr in the background (up to ~41% decrease). A variety of likely ship-plume situations at three locations at different latitudes within the global ship corridors was also studied to determine the extent of the enhancements in the HCHOlevels in the marine boundary layer (MBL) influenced by ship emissions. It was found that the ship-plume HCHO levels could be 20.5–434.9 pptv higher than the background HCHO levels depending on the latitudinal locations of the ship plumes (i.e., intensity of solar radiation and temperature), MBL stability and NOx emission rates. On the other hand, NMVOC emissions from ships were not found to be a primary source of photochemical HCHOproduction inside ship plumes due to their rapid and individual dilution. However, the diluted NMVOCs would contribute to the HCHO productions in the background air. The greater impact of ship-plume photochemistry on the atmospheric MBL oxidation cycles, global climate, and marine eco-system in the global ship corridors are also discussed based on the results in this study.

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Degan, Germano, Luca Braidotti, Alberto Marinò, and Vittorio Bucci. "LCTC Ships Concept Design in the North Europe- Mediterranean Transport Scenario Focusing on Intact Stability Issues." Journal of Marine Science and Engineering 9, no. 3 (March 4, 2021): 278. http://dx.doi.org/10.3390/jmse9030278.

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In late years, the size of RoRo cargo ships has continuously increased, leading to the so-called Large Car Truck Carriers (LCTC). The design of these vessels introduced new challenges that shall be considered during the ship design since the conceptual stage, which has a very strong impact on the technical and economic performances of the vessel during all its life-cycle. In this work, the concept design of an LCTC is presented based on Multi-Attribute Decision Making (MADM). A large set of design alternatives have been generated and compared in order to find out the most promising feasible designs. The proposed approach is based on a Mathematical Design Model (MDM) capable to assess all the main technical and economic characteristics for each design. Among the others, here focus has been done on the ship stability to assure the compliance with statutory rules within the MDM. A new stability metamodel has been developed capable to define the cross curves of stability at the concept design stage. The proposed MADM methodology has been applied to North Europe-Mediterranean transport scenario highlighting the impact of main particulars describing hull geometry on the technical and economic performances of an LCTC ship.

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Hu, Yihuai, Juanjuan Tang, Shuye Xue, and Shewen Liu. "Stability criterion and its calculation for sail-assisted ship." International Journal of Naval Architecture and Ocean Engineering 7, no. 1 (January 1, 2015): 1–9. http://dx.doi.org/10.1515/ijnaoe-2015-0001.

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ABSTRACTStability criterion and its calculation are the crucial issue in the application of sail-assisted ship. How- ever, there is at present no specific criterion and computational methods for the stability of sail-assisted ship. Based on the stability

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46

Huang, Yifeng, and Paul D. Sclavounos. "Nonlinear Ship Motions." Journal of Ship Research 42, no. 02 (June 1, 1998): 120–30. http://dx.doi.org/10.5957/jsr.1998.42.2.120.

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A nonlinear numerical method has been developed to compute motion responses for a ship traveling in steep ambient waves. The method is based on an approximate theory and is an extension to a well-established linear time-domain numerical method. The nonlinear solution is found to be greatly improved over the classical linear and quasi-nonlinear solutions, in comparison to experimental measurements for conventional commercial ships. Through this study, it is also demonstrated that the free surface hydrodynamic nonlinearities are at least as important as, if not more than, the hydrostatic and Froude-Krylov nonlinearities. Stability, consistency and convergence for the nonlinear method are also addressed.

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Szelangiewicz, Tadeusz, and Katarzyna Żelazny. "Impact of Waves on Dangerous Stability of Vessels on the Oceanic Route." New Trends in Production Engineering 1, no. 1 (October 1, 2018): 469–77. http://dx.doi.org/10.2478/ntpe-2018-0058.

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Abstract Stability is one of the most important properties of the ship. The greatest influence on stability and thus on the possibility of loss of stability have the rolling of the ship on the wave. Mathematical models describing rolling on wave are complicated, and their solution, especially in the irregular wave, is only possible with numerical methods in the time domain. Large rolling, until the ship capsize, formation not only on the beam wave, but also on the following wave. Various models describing rolling (linear and nonlinear, regular and irregular wave, and constant or variable restoring moment) are presented. The predicted level hazard of stability of the ship depends on the direction of the wave and the cases where the level of hazard will be greatest.

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Ngongi, Werneld Egno, and Jia Lu Du. "A High-Gain Observer-Based Pd Controller Design for Dynamic Positioning of Ships." Applied Mechanics and Materials 490-491 (January 2014): 803–8. http://dx.doi.org/10.4028/www.scientific.net/amm.490-491.803.

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This paper addresses the problem of the dynamic positioning system of surface ships in the presence of constant environmental disturbances. In this paper we propose a high-gain observer-based PD controller to estimate unmeasured velocities of a surface ship. Lyapunov stability theory is applied to prove its stability. Finally, simulation is carried out using SIMULINK and appropriate results are obtained to illustrate the effectiveness and performance of proposed controller.

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Alford, Laura, Atul Banik, Vadim Belenky, Katrin Ellermann, Hirotada Hashimoto, Atsuo Maki, Leigh McCue, et al. "Discussion on Analytical Approaches to the Study of Vessel Dynamics—Outcomes of the Two-Part Minisymposium at the 2007 SIAM Conference on Applications of Dynamical Systems." Marine Technology and SNAME News 45, no. 04 (October 1, 2008): 211–20. http://dx.doi.org/10.5957/mt1.2008.45.4.211.

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While the study of ship stability dates back to Archimedes, modern research on vessel dynamics is at the forefront of applied mathematics. Large-amplitude ship motions result in strongly nonlinear, even chaotic behavior. The current trends toward high-speed and unique hullform vessels in commercial and military applications have broadened the need for robust mathematical approaches to studying the dynamics of these innovative ships. The presentations in this minisymposium focus on analytical formulations to model and understand the complicated dynamics leading to vessel phenomena such as capsizing, broaching, and parametric rolling.

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Song, C. H., H. S. Kim, R. von Glasow, P. Brimblecombe, J. Kim, R. J. Park, J. H. Woo, and Y. H. Kim. "Source identification and budget analysis on elevated levels of formaldehyde within the ship plumes: a ship-plume photochemical/dynamic model analysis." Atmospheric Chemistry and Physics 10, no. 23 (December 15, 2010): 11969–85. http://dx.doi.org/10.5194/acp-10-11969-2010.

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Abstract. Elevated levels of formaldehyde (HCHO) along the ship corridors have been observed by satellite sensors, such as ESA/ERS-2 GOME (Global Ozone Monitoring Experiment), and were also simulated by global 3-D chemistry-transport models. In this study, three likely sources of the elevated HCHO levels in the ship plumes as well as their contributions to the elevated HCHO levels (budget) were investigated using a newly-developed ship-plume photochemical/dynamic model: (1) primary HCHO emission from ships; (2) secondary HCHO production via the atmospheric oxidation of non-methane volatile organic compounds (NMVOCs) emitted from ships; and (3) atmospheric oxidation of CH4 within the ship plumes. For this ship-plume modelling study, the ITCT 2K2 (Intercontinental Transport and Chemical Transformation 2002) ship-plume experiment, which was carried out about 100 km off the coast of California on 8 May 2002 (11:00 local standard time), was chosen as a base study case because it is the best defined in terms of (1) meteorological data, (2) in-plume chemical composition, and (3) background chemical composition. From multiple ship-plume model simulations for the ITCT 2K2 ship-plume experiment case, CH4 oxidation by elevated levels of in-plume OH radicals was found to be the main factor responsible for the elevated levels of HCHO in the ITCT 2K2 ship-plume. More than ~88% of the HCHO for the ITCT 2K2 ship-plume is produced by this atmospheric chemical process, except in the areas close to the ship stacks where the main source of the elevated HCHO levels would be primary HCHO from the ships (due to the deactivation of CH4 oxidation from the depletion of in-plume OH radicals). Because of active CH4 oxidation by OH radicals, the instantaneous chemical lifetime of CH4 (τCH4) decreased to ~0.45 yr inside the ship plume, which is in contrast to τCH4 of ~1.1 yr in the background (up to ~41% decrease) for the ITCT 2K2 ship-plume case. A variety of likely ship-plume situations at three different latitudinal locations within the global ship corridors was also studied to determine the enhancements in the HCHO levels in the marine boundary layer (MBL) influenced by ship emissions. It was found that the ship-plume HCHO levels could be 19.9–424.9 pptv higher than the background HCHO levels depending on the latitudinal locations of the ship plumes (i.e., intensity of solar radiation and temperature), MBL stability and NOx emission rates. On the other hand, NMVOC emissions from ships were not found to be a primary source of photochemical HCHO production inside ship plumes due to their rapid and individual dilution. However, the diluted NMVOCs would contribute to the HCHO productions in the background air.

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Journal articles on the topic 'Ship stability'

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