The Experts below are selected from a list of 4011 Experts worldwide ranked by ideXlab platform
Pentti Kujala - One of the best experts on this subject based on the ideXlab platform.
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a risk informed Ship Collision alert system framework and application
Safety Science, 2015Co-Authors: Floris Goerlandt, Jakub Montewka, Vladimir Kuzmin, Pentti KujalaAbstract:Ship Collisions are rare occurrences with a potential to cause significant human, monetary and/or environmental loss. One element in preventing Collision accidents is the presence of a Collision alert system (CAS), providing warnings to Ship crews and/or personnel in Vessel Traffic Services of the Collision risk in a real-time operational environment. In risk research, there is a recent focus on foundational issues related to risk concepts, perspectives and methods for describing risk, with calls for work addressing these risk-theoretical issues in application areas. Despite several proposed applications for CAS, no frameworks covering these risk-theoretic issues have been presented. Hence, the purpose of this paper is twofold. First, a framework for maritime risk-informed CAS (RICAS) is presented, including a risk-conceptual basis, a systematic description of the risk perspective and a discussion on the intended use of the risk model. A theoretical framework for the operationalization of the construct “Ship Collision risk” is presented, and a method for measuring this construct is introduced. Second, the framework is applied to a case-study concerning open sea navigation. An evaluation of the proposed RICAS in comparison with earlier proposed CAS methods indicates an improved performance over these.
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impact scenario models for probabilistic risk based design for Ship Ship Collision
Marine Structures, 2013Co-Authors: Kaarle Stahlberg, Floris Goerlandt, Soren Ehlers, Pentti KujalaAbstract:Abstract A number of authors have proposed probabilistic risk based Ship design for Ship–Ship Collision, conditional to the local trading area of a vessel. The probability of Collision and consequences are determined based on the traffic conditions in which a vessel is expected to operate. This paper investigates the adequacy of currently available models for impact scenarios, i.e. models linking the traffic conditions to the conditions at the moment of Collision. An exploratory statistical model is presented to establish such a link. A probabilistic risk based design case study is performed for a fleet of RoPax vessels trading on a specified route in the Gulf of Finland. The available impact scenario models from the literature are compared with the developed probabilistic evasive maneuvering model. The results show that the impact scenario models have a very significant influence to the calculated hull breach probabilities. No well-justified impact scenario models are presently available and also the presented probabilistic evasive maneuvering model is burdened with uncertainty. Hence, to move toward a probabilistic risk based Ship design paradigm for Ship–Ship Collision in a local trading area, more focus and research is needed to establish a credible link.
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Impact scenario models for probabilistic risk-based design for Ship–Ship Collision
Marine Structures, 2013Co-Authors: Kaarle Stahlberg, Floris Goerlandt, Soren Ehlers, Pentti KujalaAbstract:Abstract A number of authors have proposed probabilistic risk based Ship design for Ship–Ship Collision, conditional to the local trading area of a vessel. The probability of Collision and consequences are determined based on the traffic conditions in which a vessel is expected to operate. This paper investigates the adequacy of currently available models for impact scenarios, i.e. models linking the traffic conditions to the conditions at the moment of Collision. An exploratory statistical model is presented to establish such a link. A probabilistic risk based design case study is performed for a fleet of RoPax vessels trading on a specified route in the Gulf of Finland. The available impact scenario models from the literature are compared with the developed probabilistic evasive maneuvering model. The results show that the impact scenario models have a very significant influence to the calculated hull breach probabilities. No well-justified impact scenario models are presently available and also the presented probabilistic evasive maneuvering model is burdened with uncertainty. Hence, to move toward a probabilistic risk based Ship design paradigm for Ship–Ship Collision in a local trading area, more focus and research is needed to establish a credible link.
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influences of variables on Ship Collision probability in a bayesian belief network model
Reliability Engineering & System Safety, 2012Co-Authors: Maria Hanninen, Pentti KujalaAbstract:Abstract The influences of the variables in a Bayesian belief network model for estimating the role of human factors on Ship Collision probability in the Gulf of Finland are studied for discovering the variables with the largest influences and for examining the validity of the network. The change in the so-called causation probability is examined while observing each state of the network variables and by utilizing sensitivity and mutual information analyses. Changing course in an encounter situation is the most influential variable in the model, followed by variables such as the Officer of the Watch's action, situation assessment, danger detection, personal condition and incapacitation. The least influential variables are the other distractions on bridge, the bridge view, maintenance routines and the officer's fatigue. In general, the methods are found to agree on the order of the model variables although some disagreements arise due to slightly dissimilar approaches to the concept of variable influence. The relative values and the ranking of variables based on the values are discovered to be more valuable than the actual numerical values themselves. Although the most influential variables seem to be plausible, there are some discrepancies between the indicated influences in the model and literature. Thus, improvements are suggested to the network.
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A New Definition of a Collision Zone For a Geometrical Model For Ship-Ship Collision Probability Estimation
TransNav: International Journal on Marine Navigation and Safety of Sea Transportation, 2011Co-Authors: Jakub Montewka, Floris Goerlandt, Pentti KujalaAbstract:In this paper, a study on a newly developed geometrical model for Ship-Ship Collisions probability estimation is conducted. Most of the models that are used for Ship-Ship Collision consider a Collision be-tween two Ships a physical contact between them. The model discussed in this paper defines the Collision criterion in a novel way. A critical distance between two meeting Ships at which such meeting situation can be considered a Collision is calculated with the use of a Ship motion model. This critical distance is named the minimum distance to Collision (MDTC). Numerous factors affect the MDTC value: a Ship type, an angle of intersection of Ships’ courses, a relative bearing between encountering Ships and a maneuvering pattern. They are discussed in the paper.
Floris Goerlandt - One of the best experts on this subject based on the ideXlab platform.
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a risk informed Ship Collision alert system framework and application
Safety Science, 2015Co-Authors: Floris Goerlandt, Jakub Montewka, Vladimir Kuzmin, Pentti KujalaAbstract:Ship Collisions are rare occurrences with a potential to cause significant human, monetary and/or environmental loss. One element in preventing Collision accidents is the presence of a Collision alert system (CAS), providing warnings to Ship crews and/or personnel in Vessel Traffic Services of the Collision risk in a real-time operational environment. In risk research, there is a recent focus on foundational issues related to risk concepts, perspectives and methods for describing risk, with calls for work addressing these risk-theoretical issues in application areas. Despite several proposed applications for CAS, no frameworks covering these risk-theoretic issues have been presented. Hence, the purpose of this paper is twofold. First, a framework for maritime risk-informed CAS (RICAS) is presented, including a risk-conceptual basis, a systematic description of the risk perspective and a discussion on the intended use of the risk model. A theoretical framework for the operationalization of the construct “Ship Collision risk” is presented, and a method for measuring this construct is introduced. Second, the framework is applied to a case-study concerning open sea navigation. An evaluation of the proposed RICAS in comparison with earlier proposed CAS methods indicates an improved performance over these.
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a probabilistic model for accidental cargo oil outflow from product tankers in a Ship Ship Collision
Marine Pollution Bulletin, 2014Co-Authors: Floris Goerlandt, Jakub MontewkaAbstract:In risk assessment of maritime transportation, estimation of accidental oil outflow from tankers is important for assessing environmental impacts. However, there typically is limited data concerning the specific structural design and tank arrangement of Ships operating in a given area. Moreover, there is uncertainty about the accident scenarios potentially emerging from Ship encounters. This paper proposes a Bayesian network (BN) model for reasoning under uncertainty for the assessment of accidental cargo oil outflow in a Ship–Ship Collision where a product tanker is struck. The BN combines a model linking impact scenarios to damage extent with a model for estimating the tank layouts based on limited information regarding the Ship. The methodology for constructing the model is presented and output for two accident scenarios is shown. The discussion elaborates on the issue of model validation, both in terms of the BN and in light of the adopted uncertainty/bias-based risk perspective.
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impact scenario models for probabilistic risk based design for Ship Ship Collision
Marine Structures, 2013Co-Authors: Kaarle Stahlberg, Floris Goerlandt, Soren Ehlers, Pentti KujalaAbstract:Abstract A number of authors have proposed probabilistic risk based Ship design for Ship–Ship Collision, conditional to the local trading area of a vessel. The probability of Collision and consequences are determined based on the traffic conditions in which a vessel is expected to operate. This paper investigates the adequacy of currently available models for impact scenarios, i.e. models linking the traffic conditions to the conditions at the moment of Collision. An exploratory statistical model is presented to establish such a link. A probabilistic risk based design case study is performed for a fleet of RoPax vessels trading on a specified route in the Gulf of Finland. The available impact scenario models from the literature are compared with the developed probabilistic evasive maneuvering model. The results show that the impact scenario models have a very significant influence to the calculated hull breach probabilities. No well-justified impact scenario models are presently available and also the presented probabilistic evasive maneuvering model is burdened with uncertainty. Hence, to move toward a probabilistic risk based Ship design paradigm for Ship–Ship Collision in a local trading area, more focus and research is needed to establish a credible link.
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Impact scenario models for probabilistic risk-based design for Ship–Ship Collision
Marine Structures, 2013Co-Authors: Kaarle Stahlberg, Floris Goerlandt, Soren Ehlers, Pentti KujalaAbstract:Abstract A number of authors have proposed probabilistic risk based Ship design for Ship–Ship Collision, conditional to the local trading area of a vessel. The probability of Collision and consequences are determined based on the traffic conditions in which a vessel is expected to operate. This paper investigates the adequacy of currently available models for impact scenarios, i.e. models linking the traffic conditions to the conditions at the moment of Collision. An exploratory statistical model is presented to establish such a link. A probabilistic risk based design case study is performed for a fleet of RoPax vessels trading on a specified route in the Gulf of Finland. The available impact scenario models from the literature are compared with the developed probabilistic evasive maneuvering model. The results show that the impact scenario models have a very significant influence to the calculated hull breach probabilities. No well-justified impact scenario models are presently available and also the presented probabilistic evasive maneuvering model is burdened with uncertainty. Hence, to move toward a probabilistic risk based Ship design paradigm for Ship–Ship Collision in a local trading area, more focus and research is needed to establish a credible link.
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A New Definition of a Collision Zone For a Geometrical Model For Ship-Ship Collision Probability Estimation
TransNav: International Journal on Marine Navigation and Safety of Sea Transportation, 2011Co-Authors: Jakub Montewka, Floris Goerlandt, Pentti KujalaAbstract:In this paper, a study on a newly developed geometrical model for Ship-Ship Collisions probability estimation is conducted. Most of the models that are used for Ship-Ship Collision consider a Collision be-tween two Ships a physical contact between them. The model discussed in this paper defines the Collision criterion in a novel way. A critical distance between two meeting Ships at which such meeting situation can be considered a Collision is calculated with the use of a Ship motion model. This critical distance is named the minimum distance to Collision (MDTC). Numerous factors affect the MDTC value: a Ship type, an angle of intersection of Ships’ courses, a relative bearing between encountering Ships and a maneuvering pattern. They are discussed in the paper.
Sheng Liu - One of the best experts on this subject based on the ideXlab platform.
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Modeling of Ship Collision Risk Based on Cloud Model
IEEE Access, 2020Co-Authors: Hongdan Liu, Lanyong Zhang, Sheng LiuAbstract:Existing models for assessing Ship Collision risk involve complex calculations that complicate the simultaneous qualitative and quantitative analysis of the factors affecting Ship navigation safety. Therefore, these models often exhibit slow generation of the risk index and evaluation results with reduced accuracy. To resolve these issues, we model the Ship Collision risk based on the cloud model theory. Specifically, we select “distance of closest point of approach (DCPA)” and “time to closest point of approach (TCPA)” as the main factors affecting the Ship Collision risk and analyze the data of DCPA, TCPA, and Collision risk index (CRI) based on their cloud models. By combining these analyses with a double-condition-single-rule generator, we construct a cloud model for Ship Collision risk and finally develop a cloud model-based inference engine system to assess Ship Collision risk. This engine allows us to establish different Ship Collision risk analysis models according to the scenario encountered by the Ship, which can be used to verify the feasibility of the proposed algorithm for Ship Collision risk modeling. Through comparisons with traditional Ship Collision risk models, the proposed Ship Collision risk model is found to be superior owing to its simple implementation, accurate results, and shorter time required to generate the risk model. The model established in this study enables the crew to determine the key objects to be avoided in case of potential Collision with multiple Ships. At last,analysis and research of cloud model Ship Collision risk based on global sensitivity and uncertainty are done to reduce the dimension of the risk parameters and show the main factors of unstable Collision risk,therefore,the uncertain results in the calculation of the degree of danger are avoided, some reasonable suggestions are proposed for real navigation safety. the maritime pilot can make correct decisions promptly to reduce or avoid the occurrence of Collision accidents.
Hongdan Liu - One of the best experts on this subject based on the ideXlab platform.
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Evaluation Modeling Establishment for the Risk Degree of Ship Collision
Application of Intelligent Systems in Multi-modal Information Analytics, 2020Co-Authors: Hongdan Liu, Yue SunAbstract:Aim to solve the problem that the qualitative and quantitative the influencing factors of Ship navigation safety is to be difficult to merger analysis, due to the large amount of calculation and complicated realization process of Ship Collision risk model, the strategy of risk degree of Ship Collision evaluation based on the cloud model theory is introduced, the data of cloud model of DCPA (Distance to closed point of approach), TCPA (Time to closest point of approach) and CRI (Collision Risk Level) is formed to reasoning risk degree of Ship Collision based on double conditional single rule generator. According to the different Ship encounter situation, the order is sorted on the Collision risk degree between own and target Ship by the cloud modeling inference mechanism. Thus, the availability and feasibility of this algorithm are verified in Ship Collision risk modeling. The establishment of this model enables the crew members to determine the key Collision avoidance objects in time, to reduce or avoid the occurrence of Collision accidents at the source.
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Modeling of Ship Collision Risk Based on Cloud Model
IEEE Access, 2020Co-Authors: Hongdan Liu, Lanyong Zhang, Sheng LiuAbstract:Existing models for assessing Ship Collision risk involve complex calculations that complicate the simultaneous qualitative and quantitative analysis of the factors affecting Ship navigation safety. Therefore, these models often exhibit slow generation of the risk index and evaluation results with reduced accuracy. To resolve these issues, we model the Ship Collision risk based on the cloud model theory. Specifically, we select “distance of closest point of approach (DCPA)” and “time to closest point of approach (TCPA)” as the main factors affecting the Ship Collision risk and analyze the data of DCPA, TCPA, and Collision risk index (CRI) based on their cloud models. By combining these analyses with a double-condition-single-rule generator, we construct a cloud model for Ship Collision risk and finally develop a cloud model-based inference engine system to assess Ship Collision risk. This engine allows us to establish different Ship Collision risk analysis models according to the scenario encountered by the Ship, which can be used to verify the feasibility of the proposed algorithm for Ship Collision risk modeling. Through comparisons with traditional Ship Collision risk models, the proposed Ship Collision risk model is found to be superior owing to its simple implementation, accurate results, and shorter time required to generate the risk model. The model established in this study enables the crew to determine the key objects to be avoided in case of potential Collision with multiple Ships. At last,analysis and research of cloud model Ship Collision risk based on global sensitivity and uncertainty are done to reduce the dimension of the risk parameters and show the main factors of unstable Collision risk,therefore,the uncertain results in the calculation of the degree of danger are avoided, some reasonable suggestions are proposed for real navigation safety. the maritime pilot can make correct decisions promptly to reduce or avoid the occurrence of Collision accidents.
Jakub Montewka - One of the best experts on this subject based on the ideXlab platform.
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a risk informed Ship Collision alert system framework and application
Safety Science, 2015Co-Authors: Floris Goerlandt, Jakub Montewka, Vladimir Kuzmin, Pentti KujalaAbstract:Ship Collisions are rare occurrences with a potential to cause significant human, monetary and/or environmental loss. One element in preventing Collision accidents is the presence of a Collision alert system (CAS), providing warnings to Ship crews and/or personnel in Vessel Traffic Services of the Collision risk in a real-time operational environment. In risk research, there is a recent focus on foundational issues related to risk concepts, perspectives and methods for describing risk, with calls for work addressing these risk-theoretical issues in application areas. Despite several proposed applications for CAS, no frameworks covering these risk-theoretic issues have been presented. Hence, the purpose of this paper is twofold. First, a framework for maritime risk-informed CAS (RICAS) is presented, including a risk-conceptual basis, a systematic description of the risk perspective and a discussion on the intended use of the risk model. A theoretical framework for the operationalization of the construct “Ship Collision risk” is presented, and a method for measuring this construct is introduced. Second, the framework is applied to a case-study concerning open sea navigation. An evaluation of the proposed RICAS in comparison with earlier proposed CAS methods indicates an improved performance over these.
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a probabilistic model for accidental cargo oil outflow from product tankers in a Ship Ship Collision
Marine Pollution Bulletin, 2014Co-Authors: Floris Goerlandt, Jakub MontewkaAbstract:In risk assessment of maritime transportation, estimation of accidental oil outflow from tankers is important for assessing environmental impacts. However, there typically is limited data concerning the specific structural design and tank arrangement of Ships operating in a given area. Moreover, there is uncertainty about the accident scenarios potentially emerging from Ship encounters. This paper proposes a Bayesian network (BN) model for reasoning under uncertainty for the assessment of accidental cargo oil outflow in a Ship–Ship Collision where a product tanker is struck. The BN combines a model linking impact scenarios to damage extent with a model for estimating the tank layouts based on limited information regarding the Ship. The methodology for constructing the model is presented and output for two accident scenarios is shown. The discussion elaborates on the issue of model validation, both in terms of the BN and in light of the adopted uncertainty/bias-based risk perspective.
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A New Definition of a Collision Zone For a Geometrical Model For Ship-Ship Collision Probability Estimation
TransNav: International Journal on Marine Navigation and Safety of Sea Transportation, 2011Co-Authors: Jakub Montewka, Floris Goerlandt, Pentti KujalaAbstract:In this paper, a study on a newly developed geometrical model for Ship-Ship Collisions probability estimation is conducted. Most of the models that are used for Ship-Ship Collision consider a Collision be-tween two Ships a physical contact between them. The model discussed in this paper defines the Collision criterion in a novel way. A critical distance between two meeting Ships at which such meeting situation can be considered a Collision is calculated with the use of a Ship motion model. This critical distance is named the minimum distance to Collision (MDTC). Numerous factors affect the MDTC value: a Ship type, an angle of intersection of Ships’ courses, a relative bearing between encountering Ships and a maneuvering pattern. They are discussed in the paper.
