H. Kajiwara, H. Kimura, Ichiro Ishikawa, Hirofumi Yamada, Yuusuke Dakeshita, Shougo Nakashima
Summary First of all, the paper focuses the problem to construct a scheduling model of the stockyard in a shipyard in Japan, which should be verified by comparing the actual usage of facilities. Secondly it discusses the problem to apply the model to determine appropriate starting dates for block fabrication in assembly lines in order to achieve leveling of working hours. It is shown that these problems are formulated into RCPSP (Resource Constraint Project Scheduling Problem) and solved successfully using a software OptSeq(TM) developed by Prof. M. Kubo based on an RCPSP solver developed by Prof. K. Nonobe and Prof. T. Ibaraki.
{"title":"Process Scheduling of a Shipbuilding Stockyard based on RCPSP Approach","authors":"H. Kajiwara, H. Kimura, Ichiro Ishikawa, Hirofumi Yamada, Yuusuke Dakeshita, Shougo Nakashima","doi":"10.2534/jjasnaoe.31.183","DOIUrl":"https://doi.org/10.2534/jjasnaoe.31.183","url":null,"abstract":"Summary First of all, the paper focuses the problem to construct a scheduling model of the stockyard in a shipyard in Japan, which should be verified by comparing the actual usage of facilities. Secondly it discusses the problem to apply the model to determine appropriate starting dates for block fabrication in assembly lines in order to achieve leveling of working hours. It is shown that these problems are formulated into RCPSP (Resource Constraint Project Scheduling Problem) and solved successfully using a software OptSeq(TM) developed by Prof. M. Kubo based on an RCPSP solver developed by Prof. K. Nonobe and Prof. T. Ibaraki.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116704267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Yoshimura, K. Takase, Hirofumi Fukui, Hideyuki Suzuki, S. Hirabayashi
Dead ships in rough sea make strong drifting motions and sometimes cause the significant accidents such as grounding or destroying offshore structures. For the prediction of such drift motion, it is necessary that the suitable mathematical model should be provided. Although many mathematical models for the conventional maneuvering ship motion are proposed and widely used, most of them are limited within the conventional maneuvering motion. They cannot be used for the large drift angle such as 90° including the zero-ship speed turning. It is very difficult for the conventional mathematical model to express the hull forces in such drift motion. One of the authors tried to make them using crossflow drag model1), 2), 4), 5), 6). However, the above models include the longitudinal integral terms, which makes the difficulties when using for real-time simulators or system identifications. In this paper, the authors have developed a simple mathematical model that has the almost equivalent hydrodynamic force characteristics for conventional crossflow model instead of using the integral terms. The new model can also express the hydrodynamic forces with large drift and turning motion including zero ship speed condition. In order to validate the mathematical model, the drift tests in the uniform wind were carried out and the simulated results were compared with the measured data. From the comparison between experimental results and simulated them, it is found that the proposed mathematical model as well as the original crossflow drag model make it possible to predict the wide range of drift motion. Furthermore, the parameters in the proposed mathematical model can be easily obtained from the principal particulars of ship based on the regression analysis. Then the drifting simulations become very easy by using the proposed simple mathematical model and the empirical formulas of the parameters.
{"title":"Simulation of Ship Drift Motion with a Simplified Mathematical Model under the Wind","authors":"Y. Yoshimura, K. Takase, Hirofumi Fukui, Hideyuki Suzuki, S. Hirabayashi","doi":"10.2534/jjasnaoe.31.47","DOIUrl":"https://doi.org/10.2534/jjasnaoe.31.47","url":null,"abstract":"Dead ships in rough sea make strong drifting motions and sometimes cause the significant accidents such as grounding or destroying offshore structures. For the prediction of such drift motion, it is necessary that the suitable mathematical model should be provided. Although many mathematical models for the conventional maneuvering ship motion are proposed and widely used, most of them are limited within the conventional maneuvering motion. They cannot be used for the large drift angle such as 90° including the zero-ship speed turning. It is very difficult for the conventional mathematical model to express the hull forces in such drift motion. One of the authors tried to make them using crossflow drag model1), 2), 4), 5), 6). However, the above models include the longitudinal integral terms, which makes the difficulties when using for real-time simulators or system identifications. In this paper, the authors have developed a simple mathematical model that has the almost equivalent hydrodynamic force characteristics for conventional crossflow model instead of using the integral terms. The new model can also express the hydrodynamic forces with large drift and turning motion including zero ship speed condition. In order to validate the mathematical model, the drift tests in the uniform wind were carried out and the simulated results were compared with the measured data. From the comparison between experimental results and simulated them, it is found that the proposed mathematical model as well as the original crossflow drag model make it possible to predict the wide range of drift motion. Furthermore, the parameters in the proposed mathematical model can be easily obtained from the principal particulars of ship based on the regression analysis. Then the drifting simulations become very easy by using the proposed simple mathematical model and the empirical formulas of the parameters.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"60 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127578628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Kawamura, S. Yamasaki, T. Mizojiri, S. Kataoka, A. Okazaki
The Reynolds number effect on the open water characteristics of a propeller with a laminar type blade section has been studied by CFD and compared with the experiment. At a Reynolds number of model tests, the boundary layer flow over the blade is mostly laminar, while it becomes almost fully turbulent at a full scale Reynolds number. Because of this fact, the Reynolds number effect is very complicated. When the Reynolds number is increased from the model scale to the full scale, the open water efficiency first increases, and then start to decrease because of the transition of the boundary layer. As the boundary layer becomes almost fully turbulent, the open water efficiency again increases with increasing Reynolds number. It has been also shown that the transition Reynolds number of a propeller with laminar type blade section is higher than that of a propeller with MAU type blade section. The open water efficiency of a model test at a sufficiently high Reynolds number is close to that at a full scale Reynolds number. However, because the open water efficiency of model tests is significantly dependent on the Reynolds number, the selection of the Reynolds number in model tests is of critical importance.
{"title":"A Study on the Optimum Propeller at Full Scale Condition, Part 1: Effect of the Reynolds Number on the Open Water Characteristics of Propellers with Laminar Flow Blade Section","authors":"T. Kawamura, S. Yamasaki, T. Mizojiri, S. Kataoka, A. Okazaki","doi":"10.2534/jjasnaoe.29.11","DOIUrl":"https://doi.org/10.2534/jjasnaoe.29.11","url":null,"abstract":"The Reynolds number effect on the open water characteristics of a propeller with a laminar type blade section has been studied by CFD and compared with the experiment. At a Reynolds number of model tests, the boundary layer flow over the blade is mostly laminar, while it becomes almost fully turbulent at a full scale Reynolds number. Because of this fact, the Reynolds number effect is very complicated. When the Reynolds number is increased from the model scale to the full scale, the open water efficiency first increases, and then start to decrease because of the transition of the boundary layer. As the boundary layer becomes almost fully turbulent, the open water efficiency again increases with increasing Reynolds number. It has been also shown that the transition Reynolds number of a propeller with laminar type blade section is higher than that of a propeller with MAU type blade section. The open water efficiency of a model test at a sufficiently high Reynolds number is close to that at a full scale Reynolds number. However, because the open water efficiency of model tests is significantly dependent on the Reynolds number, the selection of the Reynolds number in model tests is of critical importance.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126957277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study on Simplified Formula for Long-term Predictions of Ship Response in Waves for Hull Structural Design","authors":"S. Matsui, Kyohei Shinomoto, Kei Sugimoto","doi":"10.2534/jjasnaoe.34.209","DOIUrl":"https://doi.org/10.2534/jjasnaoe.34.209","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126905368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a simulation model to evaluate an effectiveness of GHG reduction on ship transportation. Our model is extended INFINIT model, which is generalized multi-commodity network model and applicable for ship transportation system. The model makes it possible to evaluate the system with GHG emission, operating cost, and opportunity loss if the system’s capacity is short. Moreover, the method shows the detailed flow of ships, cargos, and fuels on the transportation network. As a case study, the method was applied for international transportation of iron ore. The case study demonstrates that the method can support decision-making by comparison of multiple scenarios to reduce GHG emission in shipping. Especially, it is useful in that it can evaluate those scenarios from the perspectives of not only transportation performance but also required bunkering infrastructures.
{"title":"Network Optimization Model for Evaluation of GHG Reduction on Ship Transportation","authors":"Wanaka Shinnosuke, Hiekata Kazuo, Horii Yuji","doi":"10.2534/jjasnaoe.31.205","DOIUrl":"https://doi.org/10.2534/jjasnaoe.31.205","url":null,"abstract":"This paper proposes a simulation model to evaluate an effectiveness of GHG reduction on ship transportation. Our model is extended INFINIT model, which is generalized multi-commodity network model and applicable for ship transportation system. The model makes it possible to evaluate the system with GHG emission, operating cost, and opportunity loss if the system’s capacity is short. Moreover, the method shows the detailed flow of ships, cargos, and fuels on the transportation network. As a case study, the method was applied for international transportation of iron ore. The case study demonstrates that the method can support decision-making by comparison of multiple scenarios to reduce GHG emission in shipping. Especially, it is useful in that it can evaluate those scenarios from the perspectives of not only transportation performance but also required bunkering infrastructures.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126111779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ultra-deep ocean drilling is expected to develop to deeper and deeper fields. Such drilling has some problems. One of them is that weight on bit (WOB) can not be measured in real time, that is important for drilling operation. Therefore, simulation models estimating WOB are needed. However, previous studies have shown insufficient accuracy of physics-based models. In this research, we introduced a black box model with recurrent neural networks for WOB estimation. We revealed such black box model has applicability to ultra-deep ocean drilling systems, but it has low adaptability to extrapolation. In order to compensate a black box model and a physics-based model, by combining both of them we created a new model called grey box model. This grey box model was revealed to have high accuracy. This research is expected to be a guideline of grey box model with neural networks.
{"title":"WOB Estimation during Ultra-deep Ocean Drilling by Use of Recurrent Neural Networks","authors":"T. Kaneko, R. Wada, M. Ozaki, Tomoya Inoue","doi":"10.2534/jjasnaoe.29.123","DOIUrl":"https://doi.org/10.2534/jjasnaoe.29.123","url":null,"abstract":"Ultra-deep ocean drilling is expected to develop to deeper and deeper fields. Such drilling has some problems. One of them is that weight on bit (WOB) can not be measured in real time, that is important for drilling operation. Therefore, simulation models estimating WOB are needed. However, previous studies have shown insufficient accuracy of physics-based models. In this research, we introduced a black box model with recurrent neural networks for WOB estimation. We revealed such black box model has applicability to ultra-deep ocean drilling systems, but it has low adaptability to extrapolation. In order to compensate a black box model and a physics-based model, by combining both of them we created a new model called grey box model. This grey box model was revealed to have high accuracy. This research is expected to be a guideline of grey box model with neural networks.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125963919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Chujo, K. Haneda, Yusuke Komoriyama, T. Fujiwara, K. Kokubun, Yasuhira Yamada, H. Ochi, S. Inoue
The development of FOWTs (Floating Offshore Wind Turbines) is going into the commercial stage from the demonstration one. One of the key issues for success in the commercial stage is how to reduce the construction cost. For example, watertight bulkheads in narrow space of FOWTs become obstacles to the cost reduction from the perspective of structural complexity and manufacturing. On the other hand, new IEC TS 61400-3-2 standard describes the unnecessity of the damage stability requirement under certain conditions. To secure the sufficient safety without the damage stability requirement according to the IEC TS 61400-3-2, an examination method with a probability theory and the FEM analysis is proposed in this paper. The probability of collision with cruising ships, P1, around a FOWT is estimated to use by the AIS data, and the probability of structural total loss, P2, due to the ship collision is indicated according to the total loss curve which is delivered from the FEM collision analysis. The joint probability which is represented by the product of P1 and P2 is compared to the target damage probability, 10 per year. The detailed information about this method and the results of trial analyses for the FOWT off the coast of Nagasaki Prefecture are also introduced in this paper.
{"title":"Study for Damage Stability Operation on Floating Offshore Wind Turbines in the Revised IEC Standard","authors":"T. Chujo, K. Haneda, Yusuke Komoriyama, T. Fujiwara, K. Kokubun, Yasuhira Yamada, H. Ochi, S. Inoue","doi":"10.2534/jjasnaoe.31.171","DOIUrl":"https://doi.org/10.2534/jjasnaoe.31.171","url":null,"abstract":"The development of FOWTs (Floating Offshore Wind Turbines) is going into the commercial stage from the demonstration one. One of the key issues for success in the commercial stage is how to reduce the construction cost. For example, watertight bulkheads in narrow space of FOWTs become obstacles to the cost reduction from the perspective of structural complexity and manufacturing. On the other hand, new IEC TS 61400-3-2 standard describes the unnecessity of the damage stability requirement under certain conditions. To secure the sufficient safety without the damage stability requirement according to the IEC TS 61400-3-2, an examination method with a probability theory and the FEM analysis is proposed in this paper. The probability of collision with cruising ships, P1, around a FOWT is estimated to use by the AIS data, and the probability of structural total loss, P2, due to the ship collision is indicated according to the total loss curve which is delivered from the FEM collision analysis. The joint probability which is represented by the product of P1 and P2 is compared to the target damage probability, 10 per year. The detailed information about this method and the results of trial analyses for the FOWT off the coast of Nagasaki Prefecture are also introduced in this paper.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126344200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Proposal of Wear Estimation Method for Mooring Chain of Floating Structures","authors":"Takaaki Takeuchi, K. Toh, T. Utsunomiya, K. Gotoh","doi":"10.2534/jjasnaoe.29.77","DOIUrl":"https://doi.org/10.2534/jjasnaoe.29.77","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125636524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Numerical study on Estimation of Hydrodynamic Force acting on Open-frame Underwater Vehicle","authors":"Hiroyoshi Suzuki, Yosuke Okuda, Yoshiki Nagai, T. Iseki, Yoshitaka Watanabe, Yutaka Ohta","doi":"10.2534/jjasnaoe.34.87","DOIUrl":"https://doi.org/10.2534/jjasnaoe.34.87","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129897954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of Wave-induced Coupled Dynamics Between Multi-purpose Offshore Supply Vessel and Suspended Load During Crane Lifting Operation","authors":"Kazuhisa Otsubo, Kenta Hasegawa","doi":"10.2534/jjasnaoe.33.173","DOIUrl":"https://doi.org/10.2534/jjasnaoe.33.173","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"225 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130769531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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