{"title":"Estimation of fish distribution by means of neural network using monitoring data by fishing boats","authors":"Kimitoshi Iwaba, S. Tabeta, T. Hamada, K. Mizuno","doi":"10.2534/jjasnaoe.29.117","DOIUrl":"https://doi.org/10.2534/jjasnaoe.29.117","url":null,"abstract":"It is important to understand and predict fish behavior to assess the impacts of coastal development on ecosystem or to conduct appropriate fishery management. In order to collect information for understanding fish behavior, we measured the environmental factors and the distribution of fish simultaneously by using fishing boats. The memory-type sensors were attached to the fishing gear of the small trawling boats in Ise Bay, through which the water temperature, dissolved oxygen, and depth were measured as well as position information by GPS. At the same time, fish catch of each haul by trawling were recorded to grasp the fish distribution. The obtained data provides much more information for temporal and spatial distribution of water qualities than conventional monitoring. We tried to predict resource distributions by artificial neural network using the obtained data. It is found that the environmental factor affecting the behavior of conger eel varies with respect to the months. The developed neural network could predict the horizontal distribution of the conger eel fairly well.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"9 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":"128574241","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":"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}
{"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}
{"title":"Study on the Influence of the Preheating Flame Characteristics and the Oxy-fuel Gas Cutting Performance","authors":"Cesar Pinzon, N. Osawa, Yuichi Ikegami","doi":"10.2534/jjasnaoe.29.135","DOIUrl":"https://doi.org/10.2534/jjasnaoe.29.135","url":null,"abstract":"To study the influence of the CO2 on the cutting performance, the heat input due to preheating flame qqGG, and that due to the combustion of the material being cut qqBB are estimated by performing a three-dimensional nonlinear heat conduction analysis that considers the temperature dependence of the thermomechanical properties. Spot heating tests are performed to identify the heat input parameters of the preheating gases H2 and H2-CO2. Gas cutting tests are performed to identify the characteristics of the cutting groove shape while employing the selected preheating gases. Based on the information of the spot heating, and the gas cutting tests, a three-dimensional heat conduction analysis is performed to identify the temperature fields along the thickness direction of the workpiece. A new technique for the estimation of the temperature fields considering inclined cutting-fronts based on Matsuyama’s theory is proposed. The role of the preheating heat input and the material combustion heat input for the selected gases is examined. Based on the simulation results of this study, CO2 deterioration mechanism on the cutting performance is discussed. From the study, the following results were obtained: (1) A new procedure for the kerf temperature estimation throughout the plate thickness based on the two-dimensional analysis of Matsuyama is established. The procedure allows a smooth and continuous temperature distribution through the plate thickness direction. (2) By applying the proposed procedure, it is possible to estimate the three-dimensional kerf temperature distribution on thick plates and allows the consideration of inclined cutting fronts. (3) By evaluating the preheating, and the material combustion heat input, it is observed a substantial declined in qqGG when employing CO2 while qqBB remains unchanged regardless of the employed preheating gas.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"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":"130060347","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}
Yukihide Yoshihara, N. Osawa, H. Murakawa, Dai Peiyuan
{"title":"Study on the Estimation Method for Welding Fatigue Mean Stress Effect Independently from Failure Mode and Joint Type","authors":"Yukihide Yoshihara, N. Osawa, H. Murakawa, Dai Peiyuan","doi":"10.2534/jjasnaoe.36.69","DOIUrl":"https://doi.org/10.2534/jjasnaoe.36.69","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"31 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":"122530758","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}
Tomoki Taniguchi, T. Fujiwara, Jun Umeda, T. Nimura, T. Katayama
{"title":"Validation of Real-Time Nonlinear Model Predictive Control on Point Absorber Type Wave Energy Converter by Tank Test","authors":"Tomoki Taniguchi, T. Fujiwara, Jun Umeda, T. Nimura, T. Katayama","doi":"10.2534/jjasnaoe.33.247","DOIUrl":"https://doi.org/10.2534/jjasnaoe.33.247","url":null,"abstract":"Real-time implementation of a nonlinear model predictive control (NMPC) for a point absorber type wave energy converter (PAWEC) with a tubular air cored permanent magnet generator is experimentally validated through tank model tests. The control inputs of the NMPC were updated by the differential equation to trace the solution of an associated two-point boundary-value problem. Two conventional control strategies, the resistive load control and the approximate complex-conjugate control with considering the copper loss (ACL), and the NMPC were implemented to the PAWEC model. The floater heave motion, control force of the generator, and power generation characteristics were compared in these control strategies. The power generation performance of the NNPC was the same level of that of the ACL in regular and irregular waves. The sensitivities to the linear viscous damping estimation error and to the wave excitation force estimation error in the NMPC were experimentally evaluated by the tank model tests.","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"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":"122636206","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":"Fuel Saving Evaluation of a Rotor Ship in Actual Seas","authors":"N. Sogihara, K. Kume","doi":"10.2534/jjasnaoe.35.29","DOIUrl":"https://doi.org/10.2534/jjasnaoe.35.29","url":null,"abstract":"","PeriodicalId":192323,"journal":{"name":"Journal of the Japan Society of Naval Architects and Ocean Engineers","volume":"35 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":"123544904","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
{"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":"Evaluation of the Kinetic Performance of a High-Speed Planing Vehicle","authors":"K. Yukawa, Kenta Hasegawa, K. Ishida, Shota Saito","doi":"10.2534/jjasnaoe.36.15","DOIUrl":"https://doi.org/10.2534/jjasnaoe.36.15","url":null,"abstract":"","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":"129317921","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}