A. Klanac - Academia.edu (original) (raw)
Papers by A. Klanac
Alan Klanac, as2con-alveus, Rijeka/Croatia, alan.klanac@as2con.com Petar Nikolić, as2con-alveus R... more Alan Klanac, as2con-alveus, Rijeka/Croatia, alan.klanac@as2con.com Petar Nikolić, as2con-alveus Rijeka/Croatia & Faculty of engineering, University of Rijeka, Rijeka/Croatia, petar.nikolic@as2con.com Maja Kovač, as2con-alveus, Rijeka/Croatia & Faculty of engineering, University of Rijeka, Rijeka/Croatia, maja.kovac@as2con.com Jon McGregor, Bureau Veritas, Neuilly-sur-Seine Cdx/France, jon.mcgregor@bureauveritas.com ECONOMICS AND ENVIRONMENTAL IMPACT OF SHIP SPEED REDUCTION FOR AFRAMax TANKERS ...
Advancements in marine structures. London: Taylor & Francis, Mar 1, 2007
COMPIT’2008, 2008
The paper gives an overview over the EC project IMPROVE. The project develops a decision support ... more The paper gives an overview over the EC project IMPROVE. The project develops a decision support system for a methodological assessment of ship designs to provide a rational basis for making decisions pertaining to the design, production and operation of three next-generation ship types (LNG, RoPax, chemical tanker). The system is expected to reduce life-cycle costs and improve ship performance.
At present ships are designed to satisfy the minimum requirements for safety. And history shows t... more At present ships are designed to satisfy the minimum requirements for safety. And history shows that this practice does not suffice, and nor is it sustainable. A new paradigm is needed. This thesis aims to contribute in that respect by proposing a design method that should move ship safety beyond the minimum requirements as much as possible and as long as it is economically sound. The thesis focuses mostly on environmental safety in the event of accidents such as collisions and grounding. A special feature is the consideration of maritime stakeholder preferences regarding safety and profitability. This is an underlying element in all the analysis performed and conclusions reached. This design method features new approaches in multi-objective optimization of ship structures and in advanced decision making for design selection. The multi-objective optimization is based on evolutionary algorithms, more precisely the genetic algorithm (GA) with advanced treatment of design constraints and objectives. Through the approach of vectorization, the GA becomes not only more efficient, but also more flexible in use, bearing in mind the complexity and demands of accident analysis for optimization. The decision making is established on the concepts of Game Theory, resulting in a new criterion for design selection, the Competitive Optimum, based on the maximal concurrent satisfaction of stakeholder preferences. The proposed design method is intended in particular for ship structural design projects, permitting the definition of hull structural scantlings, or even hull topology if desired. The approaches to multi-objective optimization and design selection that are introduced possess a wider basis of application, and are extensible to other fields in maritime safety and naval architecture. The results of the thesis provide several relevant conclusions with an impact on practical naval architecture. For example, i) by increasing ship crashworthiness, significant risk reduction can be attained, ii) raising safety is economically justified if the benefits to the public are considered alongside those of the industry, and iii) the crashworthiness of ships can be controlled effectively with conventional double-bottom and double-sided structures.
hrcak.srce.hr
... Helsinki University of Technology/Ship Laboratory has done active research during the past 10... more ... Helsinki University of Technology/Ship Laboratory has done active research during the past 10 ... marine applications, main benefits and prob-lem areas of the panels as well ... hoistable cardeck is also presented proving some of the described benefits of all steel sandwich panels. ...
Present day ship design is faced with a difficulty to successfully integrate multiple design tool... more Present day ship design is faced with a difficulty to successfully integrate multiple design tools. This paper introduces ng.zine, a new design system intended for conceptual and preliminary ship design, aiming to make the design tool integration easy. ng.zine acts through the flexible XML database, storing and on-demand supplying current and previous values of significant ship parameters and attributes. It does so without a demand for changes in either designers working environment, or in the tools it integrates, leading to the increased flexibility of the design ...
This paper presents CAFE, a new and innovative system for rapid generation of ship concepts. The ... more This paper presents CAFE, a new and innovative system for rapid generation of ship concepts. The enhanced and simplified man-model interaction utilizes arbitrary inclined guiding planes. These guides can add, reshape, move or split any entity in a 3D model. In addition, guides can be moved along with all attached plates, girders, stiffeners and brackets. Attached elements change their shape and number of stiffeners if necessary. Another important feature is the magnetic surface concept. This enables automatic surface ...
Brodogradnja, Dec 1, 2005
Sažetak Steel sandwich panels welded by laser can offer 30-50% weight savings compared to the con... more Sažetak Steel sandwich panels welded by laser can offer 30-50% weight savings compared to the conventional steel structures. Helsinki University of Technology/Ship Laboratory has done active research during the past 10 years on various topics related to the laser welded steel sandwich panels. The work carried out includes development of design formulations for the ultimate and impact strength, analysis of fatigue strength for the joints, and development of solutions to improve the behaviour under fire. A number of research ...
This paper presents two techniques, the ‘healing’ a d ‘repairing’ that can reduce optimization ti... more This paper presents two techniques, the ‘healing’ a d ‘repairing’ that can reduce optimization time when using genetic algorithm for structural optimiz at on. The techniques can be applied to: (a) quickly find feasible designs from completely infea sible set of alternatives, and (b) to make the best infeasible designs feasible. These procedures a implemented into a genetic algorithm ‘VOP’. The performance of the original and the modi fied version of the algorithm are compared with the widespread genetic algorithm ‘NSGA-II’ for the weight optimization of a 40 000 DWT chemical tanker midship section. The results show t hat these procedures can decrease the optimization time by approximately half.
Sustainable Maritime Transportation and Exploitation of Sea Resources, 2011
ABSTRACT: In this paper, an attempt is made to define a new, proactive model for estimation the s... more ABSTRACT: In this paper, an attempt is made to define a new, proactive model for estimation the ship-ship collision consequences, assuming a RoPax as a struck ship.Therefore two major issues are addressed by this paper, one is an identification of the events that fol-low a collision between two ships at open sea and another is an estimation of the prior probabilities of the events. The latter are obtained in the course of the numerical simulations, observations and literature survey. Then the model is developed by means of Bayesian Belief Network.Furthermore the sensitivity analysis of the proposed BBN is performed and results are compared with the available models, thus an initial verification of the results is provided.Finally the probability of ship loss and human loss given a collision is estimated and the obtained results are discussed.among the nodes are given in a probabilistic way, where the prior knowledge is obtained in the course of numerical experiments, observation, analysis and simulation.In the model presented, a RoPax loss occurs if one of the two accident scenarios is met:1. The struck RoPax inner hull gets breached and the consecutive flooding is experienced, which can result further in a ship loss. Therefore the critical striking speed and angle for the given mass ratios are obtained with the use of the finite elements simulations;2. The struck RoPax has no significant hull dam-age, however the ship is set disable and is expe-riencing rolling due to wave and wind action, which can result further in ship capsizing thus ship loss. Thus the probability of RoPax capsize is calculated with the use of the six degree of freedom ship motion model.Moreover numerous variables affecting the consequences are taken into account: maritime traffic composition in the analysed sea area, col-lision dynamics, ship hydrodynamics, weather 1 INTRODUCTIONMaritime traffic poses various risks in terms of human casualties, environmental pollution or loss of property. In particular, accidents where RoPax ships are involved may pose a high risk in terms of human casualties. In the publications related to modelling the risk of a RoPax ship (Vanem and Skjong 2004), (Antao and Guedes 2006), (Vanem et al., 2007), (Konovessis and Vassalos 2008), (Guarin et al., 2009), one type of models prevails, which is based on an event-tree concept. Moreover the data used to populate the models are based on the accident statistics, thus can hardly be consid-ered proactive.Therefore this paper introduces a proactive and transferable model for the probability estimation of ship loss and human loss resulting an open sea collision with respect to a selected type of RoPax ship sailing in the selected location. However the modular nature of the model allows for continu-ous improvement. The model is based on a Baye-sian Belief Network (BBN) and utilises series of logically connected events (nodes). The relations
Alan Klanac, as2con-alveus, Rijeka/Croatia, alan.klanac@as2con.com Petar Nikolić, as2con-alveus R... more Alan Klanac, as2con-alveus, Rijeka/Croatia, alan.klanac@as2con.com Petar Nikolić, as2con-alveus Rijeka/Croatia & Faculty of engineering, University of Rijeka, Rijeka/Croatia, petar.nikolic@as2con.com Maja Kovač, as2con-alveus, Rijeka/Croatia & Faculty of engineering, University of Rijeka, Rijeka/Croatia, maja.kovac@as2con.com Jon McGregor, Bureau Veritas, Neuilly-sur-Seine Cdx/France, jon.mcgregor@bureauveritas.com ECONOMICS AND ENVIRONMENTAL IMPACT OF SHIP SPEED REDUCTION FOR AFRAMax TANKERS ...
Advancements in marine structures. London: Taylor & Francis, Mar 1, 2007
COMPIT’2008, 2008
The paper gives an overview over the EC project IMPROVE. The project develops a decision support ... more The paper gives an overview over the EC project IMPROVE. The project develops a decision support system for a methodological assessment of ship designs to provide a rational basis for making decisions pertaining to the design, production and operation of three next-generation ship types (LNG, RoPax, chemical tanker). The system is expected to reduce life-cycle costs and improve ship performance.
At present ships are designed to satisfy the minimum requirements for safety. And history shows t... more At present ships are designed to satisfy the minimum requirements for safety. And history shows that this practice does not suffice, and nor is it sustainable. A new paradigm is needed. This thesis aims to contribute in that respect by proposing a design method that should move ship safety beyond the minimum requirements as much as possible and as long as it is economically sound. The thesis focuses mostly on environmental safety in the event of accidents such as collisions and grounding. A special feature is the consideration of maritime stakeholder preferences regarding safety and profitability. This is an underlying element in all the analysis performed and conclusions reached. This design method features new approaches in multi-objective optimization of ship structures and in advanced decision making for design selection. The multi-objective optimization is based on evolutionary algorithms, more precisely the genetic algorithm (GA) with advanced treatment of design constraints and objectives. Through the approach of vectorization, the GA becomes not only more efficient, but also more flexible in use, bearing in mind the complexity and demands of accident analysis for optimization. The decision making is established on the concepts of Game Theory, resulting in a new criterion for design selection, the Competitive Optimum, based on the maximal concurrent satisfaction of stakeholder preferences. The proposed design method is intended in particular for ship structural design projects, permitting the definition of hull structural scantlings, or even hull topology if desired. The approaches to multi-objective optimization and design selection that are introduced possess a wider basis of application, and are extensible to other fields in maritime safety and naval architecture. The results of the thesis provide several relevant conclusions with an impact on practical naval architecture. For example, i) by increasing ship crashworthiness, significant risk reduction can be attained, ii) raising safety is economically justified if the benefits to the public are considered alongside those of the industry, and iii) the crashworthiness of ships can be controlled effectively with conventional double-bottom and double-sided structures.
hrcak.srce.hr
... Helsinki University of Technology/Ship Laboratory has done active research during the past 10... more ... Helsinki University of Technology/Ship Laboratory has done active research during the past 10 ... marine applications, main benefits and prob-lem areas of the panels as well ... hoistable cardeck is also presented proving some of the described benefits of all steel sandwich panels. ...
Present day ship design is faced with a difficulty to successfully integrate multiple design tool... more Present day ship design is faced with a difficulty to successfully integrate multiple design tools. This paper introduces ng.zine, a new design system intended for conceptual and preliminary ship design, aiming to make the design tool integration easy. ng.zine acts through the flexible XML database, storing and on-demand supplying current and previous values of significant ship parameters and attributes. It does so without a demand for changes in either designers working environment, or in the tools it integrates, leading to the increased flexibility of the design ...
This paper presents CAFE, a new and innovative system for rapid generation of ship concepts. The ... more This paper presents CAFE, a new and innovative system for rapid generation of ship concepts. The enhanced and simplified man-model interaction utilizes arbitrary inclined guiding planes. These guides can add, reshape, move or split any entity in a 3D model. In addition, guides can be moved along with all attached plates, girders, stiffeners and brackets. Attached elements change their shape and number of stiffeners if necessary. Another important feature is the magnetic surface concept. This enables automatic surface ...
Brodogradnja, Dec 1, 2005
Sažetak Steel sandwich panels welded by laser can offer 30-50% weight savings compared to the con... more Sažetak Steel sandwich panels welded by laser can offer 30-50% weight savings compared to the conventional steel structures. Helsinki University of Technology/Ship Laboratory has done active research during the past 10 years on various topics related to the laser welded steel sandwich panels. The work carried out includes development of design formulations for the ultimate and impact strength, analysis of fatigue strength for the joints, and development of solutions to improve the behaviour under fire. A number of research ...
This paper presents two techniques, the ‘healing’ a d ‘repairing’ that can reduce optimization ti... more This paper presents two techniques, the ‘healing’ a d ‘repairing’ that can reduce optimization time when using genetic algorithm for structural optimiz at on. The techniques can be applied to: (a) quickly find feasible designs from completely infea sible set of alternatives, and (b) to make the best infeasible designs feasible. These procedures a implemented into a genetic algorithm ‘VOP’. The performance of the original and the modi fied version of the algorithm are compared with the widespread genetic algorithm ‘NSGA-II’ for the weight optimization of a 40 000 DWT chemical tanker midship section. The results show t hat these procedures can decrease the optimization time by approximately half.
Sustainable Maritime Transportation and Exploitation of Sea Resources, 2011
ABSTRACT: In this paper, an attempt is made to define a new, proactive model for estimation the s... more ABSTRACT: In this paper, an attempt is made to define a new, proactive model for estimation the ship-ship collision consequences, assuming a RoPax as a struck ship.Therefore two major issues are addressed by this paper, one is an identification of the events that fol-low a collision between two ships at open sea and another is an estimation of the prior probabilities of the events. The latter are obtained in the course of the numerical simulations, observations and literature survey. Then the model is developed by means of Bayesian Belief Network.Furthermore the sensitivity analysis of the proposed BBN is performed and results are compared with the available models, thus an initial verification of the results is provided.Finally the probability of ship loss and human loss given a collision is estimated and the obtained results are discussed.among the nodes are given in a probabilistic way, where the prior knowledge is obtained in the course of numerical experiments, observation, analysis and simulation.In the model presented, a RoPax loss occurs if one of the two accident scenarios is met:1. The struck RoPax inner hull gets breached and the consecutive flooding is experienced, which can result further in a ship loss. Therefore the critical striking speed and angle for the given mass ratios are obtained with the use of the finite elements simulations;2. The struck RoPax has no significant hull dam-age, however the ship is set disable and is expe-riencing rolling due to wave and wind action, which can result further in ship capsizing thus ship loss. Thus the probability of RoPax capsize is calculated with the use of the six degree of freedom ship motion model.Moreover numerous variables affecting the consequences are taken into account: maritime traffic composition in the analysed sea area, col-lision dynamics, ship hydrodynamics, weather 1 INTRODUCTIONMaritime traffic poses various risks in terms of human casualties, environmental pollution or loss of property. In particular, accidents where RoPax ships are involved may pose a high risk in terms of human casualties. In the publications related to modelling the risk of a RoPax ship (Vanem and Skjong 2004), (Antao and Guedes 2006), (Vanem et al., 2007), (Konovessis and Vassalos 2008), (Guarin et al., 2009), one type of models prevails, which is based on an event-tree concept. Moreover the data used to populate the models are based on the accident statistics, thus can hardly be consid-ered proactive.Therefore this paper introduces a proactive and transferable model for the probability estimation of ship loss and human loss resulting an open sea collision with respect to a selected type of RoPax ship sailing in the selected location. However the modular nature of the model allows for continu-ous improvement. The model is based on a Baye-sian Belief Network (BBN) and utilises series of logically connected events (nodes). The relations