Pub Date : 2023-10-19DOI: 10.1007/s00773-023-00963-4
Kennedy L. S. Neves, Raul Dotta, Edgard B. Malta, Alfredo Gay Neto, Guilherme R. Franzini, Luís A. G. Bitencourt
{"title":"A digital twin to predict failure probability of an FPSO hull based on corrosion models","authors":"Kennedy L. S. Neves, Raul Dotta, Edgard B. Malta, Alfredo Gay Neto, Guilherme R. Franzini, Luís A. G. Bitencourt","doi":"10.1007/s00773-023-00963-4","DOIUrl":"https://doi.org/10.1007/s00773-023-00963-4","url":null,"abstract":"","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135730518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Automation of berthing maneuvers in shipping is a pressing issue as the berthing maneuver is one of the most stressful tasks seafarers undertake. Berthing control problems are often tackled by tracking a predefined trajectory or path. Maintaining a tracking error of zero under an uncertain environment is impossible; the tracking controller is nonetheless required to bring vessels close to desired berths. The tracking controller must prioritize the avoidance of tracking errors that may cause collisions with obstacles. This paper proposes a training method based on reinforcement learning for a trajectory tracking controller that reduces the probability of collisions with static obstacles. Via numerical simulations, we show that the proposed method reduces the probability of collisions during berthing maneuvers. Furthermore, this paper shows the tracking performance in a model experiment.
{"title":"Collision probability reduction method for tracking control in automatic docking/berthing using reinforcement learning","authors":"Kouki Wakita, Youhei Akimoto, Dimas M. Rachman, Yoshiki Miyauchi, Atsuo Maki","doi":"10.1007/s00773-023-00962-5","DOIUrl":"https://doi.org/10.1007/s00773-023-00962-5","url":null,"abstract":"Abstract Automation of berthing maneuvers in shipping is a pressing issue as the berthing maneuver is one of the most stressful tasks seafarers undertake. Berthing control problems are often tackled by tracking a predefined trajectory or path. Maintaining a tracking error of zero under an uncertain environment is impossible; the tracking controller is nonetheless required to bring vessels close to desired berths. The tracking controller must prioritize the avoidance of tracking errors that may cause collisions with obstacles. This paper proposes a training method based on reinforcement learning for a trajectory tracking controller that reduces the probability of collisions with static obstacles. Via numerical simulations, we show that the proposed method reduces the probability of collisions during berthing maneuvers. Furthermore, this paper shows the tracking performance in a model experiment.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135730023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-19DOI: 10.1007/s00773-023-00965-2
S. Vaishnavi, V. Prabhakar
{"title":"A new approach to study the nonlinear energy transfer rate for an observed wave spectrum using splines","authors":"S. Vaishnavi, V. Prabhakar","doi":"10.1007/s00773-023-00965-2","DOIUrl":"https://doi.org/10.1007/s00773-023-00965-2","url":null,"abstract":"","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135730521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Walkability assessments are becoming more popular, as walking offers numerous health, environmental, and economic benefits to communities. However, previous studies on ferry terminal walkability assessment have been inadequate. This study aimed to develop a wearable sensor system to automatically assess walkability at ferry terminals without conducting surveys. We applied seven machine learning (ML) classifiers to detect different walking environments, including flat ground (FG), downhill slope (DS), uphill slope (US), and uneven surface (UE). The ML models were evaluated across different combinations of classes: 2-class (FG vs. UE), 3-class (U) (FG vs. US vs. UE), 3-class (D) (FG vs. DS vs. UE), and 4-class (FG vs. DS vs. US vs. UE). Among these, support vector machine (SVM) classifiers had the best area under the receiver operating characteristic curves (AUCs) for the 2-class, 3-class (U), and 4-class datasets with 0.970, 0.920, and 0.922, respectively. AdaBoost (AB) performed the best in 3-class (D) with an AUC of 0.953. The least absolute shrinkage and selection operator exhibited better performance in classifying walking environments than maximum relevance and minimum redundancy. This study assessed passenger walkability and improved the built environments at ferry terminals by identifying uncomfortable walking conditions. Furthermore, the results contribute to the development of a passenger walkability evaluation system utilizing intelligent sensors and to the economic revitalization of communities near ferry terminals.
步行评估正变得越来越受欢迎，因为步行为社区提供了许多健康、环境和经济效益。然而，以往对轮渡码头步行性评价的研究并不充分。该研究旨在开发一种可穿戴传感器系统，在不进行调查的情况下自动评估渡轮码头的步行性。我们应用了7种机器学习(ML)分类器来检测不同的步行环境，包括平地(FG)、下坡(DS)、上坡(US)和不平整的表面(UE)。ML模型通过不同的分类组合进行评估:2级(FG vs UE)， 3级(U) (FG vs US vs UE)， 3级(D) (FG vs DS vs UE)和4级(FG vs DS vs US vs UE)。其中，支持向量机(SVM)分类器在2类、3类和4类数据集的受试者工作特征曲线(auc)下面积最佳，分别为0.970、0.920和0.922。AdaBoost (AB)在3类(D)中表现最佳，AUC为0.953。最小绝对收缩算子和选择算子对步行环境的分类效果优于最大关联算子和最小冗余算子。本研究评估乘客的步行能力，并透过辨识不舒适的步行环境，改善渡轮码头的建筑环境。此外，研究结果有助于开发利用智能传感器的乘客步行性评估系统，并有助于渡轮码头附近社区的经济振兴。
{"title":"Wearable Sensor-Based Walkability Assessment at Ferry Terminal using Machine Learning: A Case Study of Mokpo, Korea","authors":"Jungyeon Choi, Hwayoung Kim","doi":"10.51400/2709-6998.2700","DOIUrl":"https://doi.org/10.51400/2709-6998.2700","url":null,"abstract":"Walkability assessments are becoming more popular, as walking offers numerous health, environmental, and economic benefits to communities. However, previous studies on ferry terminal walkability assessment have been inadequate. This study aimed to develop a wearable sensor system to automatically assess walkability at ferry terminals without conducting surveys. We applied seven machine learning (ML) classifiers to detect different walking environments, including flat ground (FG), downhill slope (DS), uphill slope (US), and uneven surface (UE). The ML models were evaluated across different combinations of classes: 2-class (FG vs. UE), 3-class (U) (FG vs. US vs. UE), 3-class (D) (FG vs. DS vs. UE), and 4-class (FG vs. DS vs. US vs. UE). Among these, support vector machine (SVM) classifiers had the best area under the receiver operating characteristic curves (AUCs) for the 2-class, 3-class (U), and 4-class datasets with 0.970, 0.920, and 0.922, respectively. AdaBoost (AB) performed the best in 3-class (D) with an AUC of 0.953. The least absolute shrinkage and selection operator exhibited better performance in classifying walking environments than maximum relevance and minimum redundancy. This study assessed passenger walkability and improved the built environments at ferry terminals by identifying uncomfortable walking conditions. Furthermore, the results contribute to the development of a passenger walkability evaluation system utilizing intelligent sensors and to the economic revitalization of communities near ferry terminals.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In recent years, food safety has become a growing concern in Taiwanese society. To ensure efficient management of the supply chain within the L Aquatic Products company, it is imperative to employ reliable technical support in establishing an effective traceability management system. The traceability of products can provide managers with valuable insight into the intricacies of the supply chain. By establishing a dependable food traceability system, brand trust can be strengthened, and consumers can inquire about the movement of aquatic products within the supply chain. Blockchain technology offers features such as traceability, accountability, transparency, reliability, trust, privacy, and security, making it a viable solution for the aquatic industry. Although some researchers propose comprehensive solutions for application in aquatic companies, it is important to note that many aquatic firms are traditional companies with unique supply chain requirements. A one-size-fits-all solution may not be suitable and could lead to increased operational costs. In this research, we begin by conducting interviews with the company to gain insight into their actual production processes. Based on these findings, we design and implement a blockchain traceability process tailored specifically to the aquatic firm's supply chain. Additionally, we survey the opinions of the company's staff to ensure that the system aligns with their needs. The results indicate that the blockchain traceability system benefits the company's development.
{"title":"APPLICATION OF BLOCKCHAIN TECHNOLOGY IN AQUACULTURE MANAGEMENT","authors":"Yu-Jen Pan, Hsin-Pei Shieh","doi":"10.51400/2709-6998.2701","DOIUrl":"https://doi.org/10.51400/2709-6998.2701","url":null,"abstract":"In recent years, food safety has become a growing concern in Taiwanese society. To ensure efficient management of the supply chain within the L Aquatic Products company, it is imperative to employ reliable technical support in establishing an effective traceability management system. The traceability of products can provide managers with valuable insight into the intricacies of the supply chain. By establishing a dependable food traceability system, brand trust can be strengthened, and consumers can inquire about the movement of aquatic products within the supply chain. Blockchain technology offers features such as traceability, accountability, transparency, reliability, trust, privacy, and security, making it a viable solution for the aquatic industry. Although some researchers propose comprehensive solutions for application in aquatic companies, it is important to note that many aquatic firms are traditional companies with unique supply chain requirements. A one-size-fits-all solution may not be suitable and could lead to increased operational costs. In this research, we begin by conducting interviews with the company to gain insight into their actual production processes. Based on these findings, we design and implement a blockchain traceability process tailored specifically to the aquatic firm's supply chain. Additionally, we survey the opinions of the company's staff to ensure that the system aligns with their needs. The results indicate that the blockchain traceability system benefits the company's development.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper examines major factors of coastal erosion and measures against beach erosion at Kezailiao Coast, Taiwan. Typical examples of coastal erosion due to natural or man-made factors are reviewed. Case studies of countermeasure for beach erosion are addressed. We further analyze and discuss historical shoreline and coastal cliff recession as a result of the attack of storm surges and waves. The coastline mainly made up of cliffs (2-3m high), made of soft, easily eroded boulder sand and clay. In total, 3km of land have been lost since 1951, including villages and farm buildings. The most important impacts of beach erosion at the Kezailiao Coast include beach erosion, wave overtopping, coastal flooding, and damage to homes built on properties. This study investigates the impacts of coastal damage and examines various measures adopted in response to coastal erosion during the past 60 years at the Kezailiao Coast. We presented the prevention work through the hard soft solution against beach erosion based on their effectiveness in protecting life, property, and harmony with the adjacent environment. Key parameters for design and effectives of a submerged breakwater is in terms of different dimensionless terms are studied and discussed. Alternative defense solutions for the submerged breakwaters are suggested.
{"title":"Case Study of Coastal Erosion and Measures at Kezailiao Coast, Taiwan","authors":"Tai-Wen Hsu, Yi-Tse Tu, Jen-Yi Chang","doi":"10.51400/2709-6998.2702","DOIUrl":"https://doi.org/10.51400/2709-6998.2702","url":null,"abstract":"This paper examines major factors of coastal erosion and measures against beach erosion at Kezailiao Coast, Taiwan. Typical examples of coastal erosion due to natural or man-made factors are reviewed. Case studies of countermeasure for beach erosion are addressed. We further analyze and discuss historical shoreline and coastal cliff recession as a result of the attack of storm surges and waves. The coastline mainly made up of cliffs (2-3m high), made of soft, easily eroded boulder sand and clay. In total, 3km of land have been lost since 1951, including villages and farm buildings. The most important impacts of beach erosion at the Kezailiao Coast include beach erosion, wave overtopping, coastal flooding, and damage to homes built on properties. This study investigates the impacts of coastal damage and examines various measures adopted in response to coastal erosion during the past 60 years at the Kezailiao Coast. We presented the prevention work through the hard soft solution against beach erosion based on their effectiveness in protecting life, property, and harmony with the adjacent environment. Key parameters for design and effectives of a submerged breakwater is in terms of different dimensionless terms are studied and discussed. Alternative defense solutions for the submerged breakwaters are suggested.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marine engineers measure the liquid level (sounding depth) to calculate the volumetric content of a ship's tank. The sounding depth is determined using an ullage pipe located at specific points on the tanks. To estimate the accurate volume of liquid, considering the ship's trim and heel conditions, engineers use a tank table (sounding table) consisting of hundreds of pages. However, this method is time-consuming and lacks intermediate values for sounding depth, trim, and heel. Ship designers recommend to use linear interpolation for intermediate values, yet this process is also time-consuming. This paper proposes the implementation of an Adaptive Neuro-Fuzzy Inference System (ANFIS) to digitize the sounding table. To our knowledge, we are the first to apply the ANFIS method to develop a model for liquid volume in non-uniform geometric tanks, accounting for different trim and heel conditions of the vessel. In this study, the digitization of the sounding table using ANFIS is referred to as the Smart Sounding Table (SST). SST's accuracy is validated against experimental values, revealing an R-squared value of 0.9999, a mean absolute percentage error of 0.3515, and a root mean square error of 0.0366. These metrics clearly show that the SST algorithm accurately and reliably models experimental data. Marine engineers input three parameters (sounding depth, trim, and heel) into the SST, enabling rapid and accurate determination of liquid volume in their tanks, without the need for interpolation or exhaustive page searches.
{"title":"Smart Sounding Table Using Adaptive Neuro-Fuzzy Inference System","authors":"Osman Ünal, Nuri Akkaş","doi":"10.51400/2709-6998.2703","DOIUrl":"https://doi.org/10.51400/2709-6998.2703","url":null,"abstract":"Marine engineers measure the liquid level (sounding depth) to calculate the volumetric content of a ship's tank. The sounding depth is determined using an ullage pipe located at specific points on the tanks. To estimate the accurate volume of liquid, considering the ship's trim and heel conditions, engineers use a tank table (sounding table) consisting of hundreds of pages. However, this method is time-consuming and lacks intermediate values for sounding depth, trim, and heel. Ship designers recommend to use linear interpolation for intermediate values, yet this process is also time-consuming. This paper proposes the implementation of an Adaptive Neuro-Fuzzy Inference System (ANFIS) to digitize the sounding table. To our knowledge, we are the first to apply the ANFIS method to develop a model for liquid volume in non-uniform geometric tanks, accounting for different trim and heel conditions of the vessel. In this study, the digitization of the sounding table using ANFIS is referred to as the Smart Sounding Table (SST). SST's accuracy is validated against experimental values, revealing an R-squared value of 0.9999, a mean absolute percentage error of 0.3515, and a root mean square error of 0.0366. These metrics clearly show that the SST algorithm accurately and reliably models experimental data. Marine engineers input three parameters (sounding depth, trim, and heel) into the SST, enabling rapid and accurate determination of liquid volume in their tanks, without the need for interpolation or exhaustive page searches.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135739899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study used clinker, ground granulated blast-furnace slag (GGBS), and gypsum in a cement-grinding system to produce GGBS cement (GCE). Gypsum was used as the alkaline activator to modify the surface area of GCE and increase its compressive strength. The results revealed that the use of the gypsum activator and the modification of the surface area of GCE effectively increased the formerly inadequate compressive strength of GCE (GGBS > 60%) in the early stage. In addition, energy consumption data were obtained during the production of GCE and Portland cement (PCE) by the cement-grinding system. The calculations concerning the production proportions indicated that when GCE was produced in place of PCE, the overall demand for clinker fell by 65%. By comparison, the total energy consumption per ton of production decreased from 1539 to 602 kWh, and CO2 emissions decreased from 0.78 to 0.31 tons. Furthermore, energy efficiency and carbon-reduction efficiency both reached 60.9%. In summary, the production of GCE through the proposed cement-grinding system appears to be feasible and able to considerably increase the energy efficiency and carbon reduction efficiency of cement production.
{"title":"Production of ground granulated blast-furnace slag cement: Energy and carbon reduction efficiency of cement-grinding system","authors":"Kuan-Hung Lin, Chung-Chia Yang","doi":"10.51400/2709-6998.2696","DOIUrl":"https://doi.org/10.51400/2709-6998.2696","url":null,"abstract":"This study used clinker, ground granulated blast-furnace slag (GGBS), and gypsum in a cement-grinding system to produce GGBS cement (GCE). Gypsum was used as the alkaline activator to modify the surface area of GCE and increase its compressive strength. The results revealed that the use of the gypsum activator and the modification of the surface area of GCE effectively increased the formerly inadequate compressive strength of GCE (GGBS > 60%) in the early stage. In addition, energy consumption data were obtained during the production of GCE and Portland cement (PCE) by the cement-grinding system. The calculations concerning the production proportions indicated that when GCE was produced in place of PCE, the overall demand for clinker fell by 65%. By comparison, the total energy consumption per ton of production decreased from 1539 to 602 kWh, and CO2 emissions decreased from 0.78 to 0.31 tons. Furthermore, energy efficiency and carbon-reduction efficiency both reached 60.9%. In summary, the production of GCE through the proposed cement-grinding system appears to be feasible and able to considerably increase the energy efficiency and carbon reduction efficiency of cement production.","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-29DOI: 10.1007/s00773-023-00958-1
Jianming Miao, Wenchao Liu, Chao Peng, Xingyu Sun
{"title":"Robust path-following control of the underactuated AUV with multiple uncertainties using combined UDE and UKF","authors":"Jianming Miao, Wenchao Liu, Chao Peng, Xingyu Sun","doi":"10.1007/s00773-023-00958-1","DOIUrl":"https://doi.org/10.1007/s00773-023-00958-1","url":null,"abstract":"","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-19DOI: 10.1007/s00773-023-00959-0
P. R. Jayasree, V. Ravikumar Pandi, Hatem Zein El din, Gopinath Selvaraj
{"title":"Event-triggered coupled control of unmanned surface vehicle (USV) for setpoint tracking with linear event threshold","authors":"P. R. Jayasree, V. Ravikumar Pandi, Hatem Zein El din, Gopinath Selvaraj","doi":"10.1007/s00773-023-00959-0","DOIUrl":"https://doi.org/10.1007/s00773-023-00959-0","url":null,"abstract":"","PeriodicalId":16334,"journal":{"name":"Journal of Marine Science and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135014726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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