Pub Date : 2022-09-01DOI: 10.17736/ijope.2022.jc867
Xu Chen, D. Jeng
{"title":"Oscillatory Seabed Responses Around Two Pipelines in Tandem Under Combined Wave and Current Loading","authors":"Xu Chen, D. Jeng","doi":"10.17736/ijope.2022.jc867","DOIUrl":"https://doi.org/10.17736/ijope.2022.jc867","url":null,"abstract":"","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45674687","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 : 2022-06-01DOI: 10.17736/ijope.2022.ik09
N. Tryaskin, E. Ermolaeva, K. D. Ovchinnikov, D. V. Nikushchenko, Dmitriy S Khmara, K. Kornishin, Yaroslav Efimov, A. V. Nesterov, A. A. Skutin
Some features of the movement of tabular icebergs during their towing are examined. A tabular iceberg towed in the Barents Sea in 2017, for which surveys of the underwater and surface parts were carried out, was selected for the analysis. As a result of numerical and physical modeling, the hydrodynamic characteristics of the iceberg were obtained for different motion courses; good convergence of the results of these methods was achieved. To determine each component, the numerical simulation, based on the equations of a viscous fluid motion, was carried out. Turbulent fluid flow is described by the Reynolds-averaged Navier–Stokes and continuity equations. The k – (cid:151) SST turbulence model is used to simulate turbulence. Numerical differentiation of the equations was performed in the open-source computational fluid dynamics software Open-FOAM. It is shown that the iceberg has several positions of stable and unstable equilibria in terms of the rotation around a vertical axis, and the influence of an iceberg’s orientation on additional resistance during rough seas is considered. Obtained results may be used in planning tabular iceberg towing in different regions of the world, as well as in further studies of iceberg behavior under load.
{"title":"Features of Tabular Iceberg Towing","authors":"N. Tryaskin, E. Ermolaeva, K. D. Ovchinnikov, D. V. Nikushchenko, Dmitriy S Khmara, K. Kornishin, Yaroslav Efimov, A. V. Nesterov, A. A. Skutin","doi":"10.17736/ijope.2022.ik09","DOIUrl":"https://doi.org/10.17736/ijope.2022.ik09","url":null,"abstract":"Some features of the movement of tabular icebergs during their towing are examined. A tabular iceberg towed in the Barents Sea in 2017, for which surveys of the underwater and surface parts were carried out, was selected for the analysis. As a result of numerical and physical modeling, the hydrodynamic characteristics of the iceberg were obtained for different motion courses; good convergence of the results of these methods was achieved. To determine each component, the numerical simulation, based on the equations of a viscous fluid motion, was carried out. Turbulent fluid flow is described by the Reynolds-averaged Navier–Stokes and continuity equations. The k – (cid:151) SST turbulence model is used to simulate turbulence. Numerical differentiation of the equations was performed in the open-source computational fluid dynamics software Open-FOAM. It is shown that the iceberg has several positions of stable and unstable equilibria in terms of the rotation around a vertical axis, and the influence of an iceberg’s orientation on additional resistance during rough seas is considered. Obtained results may be used in planning tabular iceberg towing in different regions of the world, as well as in further studies of iceberg behavior under load.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47715744","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 : 2022-06-01DOI: 10.17736/ijope.2022.ak44
K. Fang, F. Yi, Jiantao Liu, Jia-wen Sun
In this study, a physical experiment is conducted in a wave flume to investigate the evolution process of a beach profile confronted by an artificial sandbar. Random waves with the JONSWAP spectrum are chosen to represent the storm wave condition. The time series of free surface elevation along the wave flume and equilibrium beach profile are acquired. The spatial variation of wave hydrodynamics, bar behavior, and morphological characteristics during the nourished beach profile evolution toward the equilibrium state is investigated. The effect of installation position, submerged depth, and median grain size of the artificial sandbar on beach erosion is discussed.
{"title":"Laboratory Study on the Effect of an Artificial Sandbar on Nourished Beach Profile Evolution","authors":"K. Fang, F. Yi, Jiantao Liu, Jia-wen Sun","doi":"10.17736/ijope.2022.ak44","DOIUrl":"https://doi.org/10.17736/ijope.2022.ak44","url":null,"abstract":"In this study, a physical experiment is conducted in a wave flume to investigate the evolution process of a beach profile confronted by an artificial sandbar. Random waves with the JONSWAP spectrum are chosen to represent the storm wave condition. The time series of free surface elevation along the wave flume and equilibrium beach profile are acquired. The spatial variation of wave hydrodynamics, bar behavior, and morphological characteristics during the nourished beach profile evolution toward the equilibrium state is investigated. The effect of installation position, submerged depth, and median grain size of the artificial sandbar on beach erosion is discussed.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43446042","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 : 2022-06-01DOI: 10.17736/ijope.2022.cl20
Ting-Yu Fan, Chin-Yu Lin, Chin-Cheng Huang
This paper is intended to study the influence of soil–structure interaction on the seismic response of jacket substructure for the Technical University of Denmark 10-MW reference wind turbine on the west coast of Taiwan. Since Taiwan is located in the circum-Pacific seismic belt, there is significant interest in assessing the behavior of a wind turbine subjected to seismic loading. Based on the flexible volume method, a finite element model was employed to quantify the contribution of foundation damping to overall damping of offshore wind turbines. The results show that foundation damping was estimated to contribute 1.28%–1.50% of critical damping to total offshore wind turbine damping. The soil–structure interaction effects have significant influence on seismic responses.
{"title":"Modeling the Influence of Soil-Structure-Interaction on Seismic Response of Jacket Substructure for the DTU 10MW Offshore Wind Turbine","authors":"Ting-Yu Fan, Chin-Yu Lin, Chin-Cheng Huang","doi":"10.17736/ijope.2022.cl20","DOIUrl":"https://doi.org/10.17736/ijope.2022.cl20","url":null,"abstract":"This paper is intended to study the influence of soil–structure interaction on the seismic response of jacket substructure for the Technical University of Denmark 10-MW reference wind turbine on the west coast of Taiwan. Since Taiwan is located in the circum-Pacific seismic belt, there is significant interest in assessing the behavior of a wind turbine subjected to seismic loading. Based on the flexible volume method, a finite element model was employed to quantify the contribution of foundation damping to overall damping of offshore wind turbines. The results show that foundation damping was estimated to contribute 1.28%–1.50% of critical damping to total offshore wind turbine damping. The soil–structure interaction effects have significant influence on seismic responses.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46960412","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 : 2022-06-01DOI: 10.17736/ijope.2022.jc856
I. Turnbull, T. King, F. Ralph
An iceberg drift model was developed for offshore oil and gas operations. Increasing forecasting accuracy is critical for making appropriate downtime decisions. Three sources of ocean current data were used to run test simulations of the model: estimates from observed iceberg drift and wind, measurements from a drifting buoy, and a three-dimensional (3D) ocean model. The average simulated iceberg position errors at 24 hours were 12% smaller for the estimated current drift simulations compared with the 3D modelled current simulations. The 17-hour iceberg position errors were 21% smaller for the buoy current drift simulation compared with the 3D modelled current simulation.
{"title":"Iceberg Drift Simulations Using Inferred, Measured, and Ocean Model Currents","authors":"I. Turnbull, T. King, F. Ralph","doi":"10.17736/ijope.2022.jc856","DOIUrl":"https://doi.org/10.17736/ijope.2022.jc856","url":null,"abstract":"An iceberg drift model was developed for offshore oil and gas operations. Increasing forecasting accuracy is critical for making appropriate downtime decisions. Three sources of ocean current data were used to run test simulations of the model: estimates from observed iceberg drift and wind, measurements from a drifting buoy, and a three-dimensional (3D) ocean model. The average simulated iceberg position errors at 24 hours were 12% smaller for the estimated current drift simulations compared with the 3D modelled current simulations. The 17-hour iceberg position errors were 21% smaller for the buoy current drift simulation compared with the 3D modelled current simulation.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47664166","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 : 2022-06-01DOI: 10.17736/ijope.2022.jc851
K. Kornishin, Yaroslav Efimov, P. A. Tarasov, Sergey Kovalev, A. Bekker, Alexander M Polomoshnov
The article investigates dependences of flat ice strength properties in the Kara, Laptev and East Siberian seas on ice structure and physical parameters (first of all, on the ice temperature). Research was based on the array of experimental data on the flat ice properties studied during 2013-2017 expeditions in the Kara, Laptev and East Siberian seas and 2016-2019 work on the research site in the Khatanga bay of the Laptev sea. Analysis of various ice strength characteristics showed similarity of ice in the Russian Arctic seas and in the Pacific Ocean. The differences in the ice strength properties at different loading rates were determined, and the variation coefficients of ice strength parameters were estimated. Dependences on ice temperature were obtained for all ice strength characteristics, and show a good approximation that can be described by a linear law. Indenter and compressive strength correlations were reformed for various types of first-year ice. Regression equations were determined in order to estimate the bending strength of ice consoles; anomalous behavior of Young's modulus of ice was observed during tests of consoles. Results of the work can be used for calculating ice loads on offshore structures, as well as for assessing icebreaking capacity of vessels passing the Northern Sea Route.
{"title":"Correlation Dependences of Level Ice Strength Properties in the Kara, Laptev, and East Siberian Seas","authors":"K. Kornishin, Yaroslav Efimov, P. A. Tarasov, Sergey Kovalev, A. Bekker, Alexander M Polomoshnov","doi":"10.17736/ijope.2022.jc851","DOIUrl":"https://doi.org/10.17736/ijope.2022.jc851","url":null,"abstract":"The article investigates dependences of flat ice strength properties in the Kara, Laptev and East Siberian seas on ice structure and physical parameters (first of all, on the ice temperature). Research was based on the array of experimental data on the flat ice properties studied during 2013-2017 expeditions in the Kara, Laptev and East Siberian seas and 2016-2019 work on the research site in the Khatanga bay of the Laptev sea. Analysis of various ice strength characteristics showed similarity of ice in the Russian Arctic seas and in the Pacific Ocean. The differences in the ice strength properties at different loading rates were determined, and the variation coefficients of ice strength parameters were estimated. Dependences on ice temperature were obtained for all ice strength characteristics, and show a good approximation that can be described by a linear law. Indenter and compressive strength correlations were reformed for various types of first-year ice. Regression equations were determined in order to estimate the bending strength of ice consoles; anomalous behavior of Young's modulus of ice was observed during tests of consoles. Results of the work can be used for calculating ice loads on offshore structures, as well as for assessing icebreaking capacity of vessels passing the Northern Sea Route.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41376175","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 : 2022-06-01DOI: 10.17736/ijope.2022.ak46
R. Kurnia, E. V. van Groesen
This paper describes a numerical implementation of a Hamiltonian Boussinesq wave-body interaction for irrotational flow as formulated in van Groesen and Andonowati (2017), with a restriction of one horizontal coordinate and a cross section of the body. Part of the HAWASSI (Hamiltonian Wave-Ship-Structure Interaction) software we developed allows for numerical discretisation of the surface waves using spectral methods. Non-smooth effects from the body-fluid interaction are included in the design of a virtual wave in the body area, which is determined by the boundary conditions on the body hull. Except for a comparison with standard cases in the literature, the performance of the code is shown by comparison with measurements of an experiment on the slow-drift motion of a rectangular barge moored above a sloping beach and interacting with irregular waves, in the barge beam direction, including the infra-gravity waves from the runup on the shore.
{"title":"Hamiltonian Boussinesq Simulation of Wave-Body Interaction Above Sloping Bottom","authors":"R. Kurnia, E. V. van Groesen","doi":"10.17736/ijope.2022.ak46","DOIUrl":"https://doi.org/10.17736/ijope.2022.ak46","url":null,"abstract":"This paper describes a numerical implementation of a Hamiltonian Boussinesq wave-body interaction for irrotational flow as formulated in van Groesen and Andonowati (2017), with a restriction of one horizontal coordinate and a cross section of the body. Part of the HAWASSI (Hamiltonian Wave-Ship-Structure Interaction) software we developed allows for numerical discretisation of the surface waves using spectral methods. Non-smooth effects from the body-fluid interaction are included in the design of a virtual wave in the body area, which is determined by the boundary conditions on the body hull. Except for a comparison with standard cases in the literature, the performance of the code is shown by comparison with measurements of an experiment on the slow-drift motion of a rectangular barge moored above a sloping beach and interacting with irregular waves, in the barge beam direction, including the infra-gravity waves from the runup on the shore.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41491881","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 : 2022-06-01DOI: 10.17736/ijope.2022.jc853
V. A. Korshunov, R. Mudrik, Dmitry A Ponomarev, Alexander A Rodionov, D. V. Nikushchenko, K. Kornishin, Yaroslav Efimov, A. Chernov, I. Svistunov
This paper describes a mathematical model of iceberg towing that considers an iceberg’s shape in an explicit form. The developed model allows for the analysis of oscillations appearing in towing systems in both stationary and dynamic modes. The proposed numerical model can be used to assess the nonlinear dynamics of the “vessel-rope-iceberg” system. An understanding of the peak values in the tow force should help to increase iceberg towing efficiency and ensure the safety of operations as a result of reduced iceberg roll and rope slide-off.
{"title":"Oscillations During Iceberg Towing","authors":"V. A. Korshunov, R. Mudrik, Dmitry A Ponomarev, Alexander A Rodionov, D. V. Nikushchenko, K. Kornishin, Yaroslav Efimov, A. Chernov, I. Svistunov","doi":"10.17736/ijope.2022.jc853","DOIUrl":"https://doi.org/10.17736/ijope.2022.jc853","url":null,"abstract":"This paper describes a mathematical model of iceberg towing that considers an iceberg’s shape in an explicit form. The developed model allows for the analysis of oscillations appearing in towing systems in both stationary and dynamic modes. The proposed numerical model can be used to assess the nonlinear dynamics of the “vessel-rope-iceberg” system. An understanding of the peak values in the tow force should help to increase iceberg towing efficiency and ensure the safety of operations as a result of reduced iceberg roll and rope slide-off.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45807315","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 : 2022-06-01DOI: 10.17736/ijope.2022.jc850
K. Kornishin, Yaroslav Efimov, D. V. Nikushchenko, Dmitriy S Khmara, N. Tryaskin, A. Andreev, A. A. Skutin, K. Smirnov
This article examines iceberg movement under the influence of wind-force, with detailed analysis of the influence of iceberg shape (both keel and sail) on the parameters of this movement. For four icebergs, studied during trials in 2016– 2017, hydrodynamic characteristics of keels and sails were determined by means of numerical and basin modeling. For these icebergs, orientation, direction, and speed of movement were calculated for different wind speeds and directions. Regression between the maximum value of the hydrodynamic drag coefficient and the geometric parameters is built based on the studied shape of sails of 10 icebergs. A formula for calculating the wind load on an iceberg depending on the parameters of its topside and a formula for calculating the drift speed of icebergs less than 75 meters long are proposed. The formulas are applied to icebergs of the southwestern part of the Kara Sea, which made it possible to estimate their drift speed and wind load under the influence of wind. The obtained results can be used in the modeling of the iceberg drift, as well as for assessing the wind impact during iceberg towing.
{"title":"Effect of Iceberg Shape on Wind-force Parameters","authors":"K. Kornishin, Yaroslav Efimov, D. V. Nikushchenko, Dmitriy S Khmara, N. Tryaskin, A. Andreev, A. A. Skutin, K. Smirnov","doi":"10.17736/ijope.2022.jc850","DOIUrl":"https://doi.org/10.17736/ijope.2022.jc850","url":null,"abstract":"This article examines iceberg movement under the influence of wind-force, with detailed analysis of the influence of iceberg shape (both keel and sail) on the parameters of this movement. For four icebergs, studied during trials in 2016– 2017, hydrodynamic characteristics of keels and sails were determined by means of numerical and basin modeling. For these icebergs, orientation, direction, and speed of movement were calculated for different wind speeds and directions. Regression between the maximum value of the hydrodynamic drag coefficient and the geometric parameters is built based on the studied shape of sails of 10 icebergs. A formula for calculating the wind load on an iceberg depending on the parameters of its topside and a formula for calculating the drift speed of icebergs less than 75 meters long are proposed. The formulas are applied to icebergs of the southwestern part of the Kara Sea, which made it possible to estimate their drift speed and wind load under the influence of wind. The obtained results can be used in the modeling of the iceberg drift, as well as for assessing the wind impact during iceberg towing.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42823110","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}
Rectangular foundations are employed as an emerging solution to support jack-up platforms, where the impact of changes in foundation shape and size compared to traditional circular foundations needs to be explicitly considered. However, few recent studies have addressed this topic. Therefore, this paper reports the deep penetration behavior of rectangular foundations in kaolin and silty clays based on centrifuge experiments and particle image velocimetry (PIV) techniques. The flow back of the soil is found to be complicated by the nonaxisymmetric characteristic of the rectangular spudcan. Sensitivity is the most critical factor affecting the flow state and bearing capacity response of different clays, and some discrepancies exist between the experimental bearing capacity results and the predicted values of the classical methods.
{"title":"Deep Penetration of Rectangular Spudcan into Single-Layer Clay","authors":"Dongshi Wang, Lindong Fan, Fei Wang, Menglan Duan, Jinjiang Wang, S. Gao","doi":"10.17736/ijope.2022.cl19","DOIUrl":"https://doi.org/10.17736/ijope.2022.cl19","url":null,"abstract":"Rectangular foundations are employed as an emerging solution to support jack-up platforms, where the impact of changes in foundation shape and size compared to traditional circular foundations needs to be explicitly considered. However, few recent studies have addressed this topic. Therefore, this paper reports the deep penetration behavior of rectangular foundations in kaolin and silty clays based on centrifuge experiments and particle image velocimetry (PIV) techniques. The flow back of the soil is found to be complicated by the nonaxisymmetric characteristic of the rectangular spudcan. Sensitivity is the most critical factor affecting the flow state and bearing capacity response of different clays, and some discrepancies exist between the experimental bearing capacity results and the predicted values of the classical methods.","PeriodicalId":50302,"journal":{"name":"International Journal of Offshore and Polar Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46785339","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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