Abstract This paper presents the results of an experimental study that investigates the compression behavior of concrete and evaluates the effect of hybrid reinforcement by multiple geometries, and total and partial confinement, using CFRP and GFRP composite materials. A total of nine (09) variants of concrete cylindrical specimens, including one (01) variant of unconfined concrete and eight (08) variants of confined concrete with different geometries were subjected to axial load compression. The objectives of this study were to verify the applicability and effectiveness of partial and total confinement to improve the behavior of concrete, evaluate the effect of the hybrid confinement used, and obtain a typical reinforced model. The results obtained clearly show the effectiveness of the hybrid confinement and partially confined concrete in improving the compressive strength and deformation of the concrete, so it is possible to replace CFRP total confinement by partially confined concrete with two CFRP layers or by a hybrid confinement with a CFRP layer in the central zone and GFRP layers on the top and bottom of the specimen.
{"title":"Effectiveness of Hybrid and Partially Confined Concrete Subjected to Axial Compressive Loading Using CFRP and GFRP Composite Materials","authors":"Y. Ghernouti, B. Rabehi","doi":"10.2478/sjce-2020-0025","DOIUrl":"https://doi.org/10.2478/sjce-2020-0025","url":null,"abstract":"Abstract This paper presents the results of an experimental study that investigates the compression behavior of concrete and evaluates the effect of hybrid reinforcement by multiple geometries, and total and partial confinement, using CFRP and GFRP composite materials. A total of nine (09) variants of concrete cylindrical specimens, including one (01) variant of unconfined concrete and eight (08) variants of confined concrete with different geometries were subjected to axial load compression. The objectives of this study were to verify the applicability and effectiveness of partial and total confinement to improve the behavior of concrete, evaluate the effect of the hybrid confinement used, and obtain a typical reinforced model. The results obtained clearly show the effectiveness of the hybrid confinement and partially confined concrete in improving the compressive strength and deformation of the concrete, so it is possible to replace CFRP total confinement by partially confined concrete with two CFRP layers or by a hybrid confinement with a CFRP layer in the central zone and GFRP layers on the top and bottom of the specimen.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"8 - 14"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48050059","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}
Abstract In this paper, the short-term behavior of a new partially pre-cast and partially encased composite (PPEC) beam is studied. This paper reports the results of a 4-point bending test on a full-scale PPEC beam and sets out the load displacement response, short-term stiffness, peak load capacity and failure mode of the proposed PPEC beam. In addition, a finite element analysis of the PPEC beam is carried out, and the numerical simulation results are compared with the test results. The results show that the finite element model can reflect the bending response of the PPEC beam. In this paper, three different calculation methods are used to compare the deflection of the PPEC beam. The results show that the values calculated by the bending-shear coupling method formula agree relatively well with the test results.
{"title":"Experimental and Numerical Investigation of Short-Term Behavior of Partially Precast and Partially Encased Composite Beams","authors":"Liufeng Zhang, Yinghua Yang","doi":"10.2478/sjce-2020-0021","DOIUrl":"https://doi.org/10.2478/sjce-2020-0021","url":null,"abstract":"Abstract In this paper, the short-term behavior of a new partially pre-cast and partially encased composite (PPEC) beam is studied. This paper reports the results of a 4-point bending test on a full-scale PPEC beam and sets out the load displacement response, short-term stiffness, peak load capacity and failure mode of the proposed PPEC beam. In addition, a finite element analysis of the PPEC beam is carried out, and the numerical simulation results are compared with the test results. The results show that the finite element model can reflect the bending response of the PPEC beam. In this paper, three different calculation methods are used to compare the deflection of the PPEC beam. The results show that the values calculated by the bending-shear coupling method formula agree relatively well with the test results.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"29 - 39"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43581130","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}
Richard Honti, J. Erdélyi, Gabriela Bariczová, T. Funtík, Pavol Mayer
Abstract One of the most important parts of construction work is the verification of the geometry of the parts of structures and buildings constructed. Today this procedure is often semi- or fully automated. The paper introduces an approach for the automated verification of parts of buildings, by comparing the design of a building (as-planned model), derived from a Building Information Model (BIM) in an Industry Foundation Classes (IFC) exchange format to a terrestrial laser scanning (TLS) point cloud (as-built model). The approach proposed has three main steps. The process begins with the acquisition of information from the as-planned model in the IFC exchange format; the second step is the automated (wall) plane segmentation from the point cloud. In the last step, the two models mentioned are compared to determine the deviations from the design, and the as-built wall flatness quantification is also executed. The potential of the proposed algorithm is shown in a case-study.
{"title":"Automated Verification of Building Components Using BIM Models and Point Clouds","authors":"Richard Honti, J. Erdélyi, Gabriela Bariczová, T. Funtík, Pavol Mayer","doi":"10.2478/sjce-2020-0019","DOIUrl":"https://doi.org/10.2478/sjce-2020-0019","url":null,"abstract":"Abstract One of the most important parts of construction work is the verification of the geometry of the parts of structures and buildings constructed. Today this procedure is often semi- or fully automated. The paper introduces an approach for the automated verification of parts of buildings, by comparing the design of a building (as-planned model), derived from a Building Information Model (BIM) in an Industry Foundation Classes (IFC) exchange format to a terrestrial laser scanning (TLS) point cloud (as-built model). The approach proposed has three main steps. The process begins with the acquisition of information from the as-planned model in the IFC exchange format; the second step is the automated (wall) plane segmentation from the point cloud. In the last step, the two models mentioned are compared to determine the deviations from the design, and the as-built wall flatness quantification is also executed. The potential of the proposed algorithm is shown in a case-study.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"13 - 19"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42486754","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}
Abstract In this paper, we have developed an efficient hybrid meta-heuristic algorithm for structural cost optimization of a waffle slab and have also solved the relevant optimization problems. The cost of the waffle slab is considered to be the objective function, and the design is based on the American Concrete Institute’s ACI 318-08 standard. This algorithm utilizes the recently developed mouth-brooding fish (MBF) algorithm as the main engine and uses the favorable properties of the colliding bodies optimization (CBO) algorithm. The performance of this algorithm is compared with MBF, CBO, harmony search (HS), particle swarm optimization (PSO), democratic particle swarm optimization (DPSO), charged system search (CSS) and enhanced charged system search (ECSS). The numerical results demonstrate that the proposed algorithm can construct promising results and has merits in solving challenging optimization problems.
{"title":"A New Hybrid Algorithm for Cost Optimization of Waffle Slab","authors":"D. Shayegan, A. Lork, S. Hashemi","doi":"10.2478/sjce-2020-0022","DOIUrl":"https://doi.org/10.2478/sjce-2020-0022","url":null,"abstract":"Abstract In this paper, we have developed an efficient hybrid meta-heuristic algorithm for structural cost optimization of a waffle slab and have also solved the relevant optimization problems. The cost of the waffle slab is considered to be the objective function, and the design is based on the American Concrete Institute’s ACI 318-08 standard. This algorithm utilizes the recently developed mouth-brooding fish (MBF) algorithm as the main engine and uses the favorable properties of the colliding bodies optimization (CBO) algorithm. The performance of this algorithm is compared with MBF, CBO, harmony search (HS), particle swarm optimization (PSO), democratic particle swarm optimization (DPSO), charged system search (CSS) and enhanced charged system search (ECSS). The numerical results demonstrate that the proposed algorithm can construct promising results and has merits in solving challenging optimization problems.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"40 - 46"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42831281","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}
Abstract Deficient or deteriorating reinforced-concrete columns in many existing structures have to be strengthened using economical, efficient, and fast methods. In the present study, different strengthening techniques to improve the load-carrying capacity of reinforced concrete (RC) columns have been compared. Five groups of fifteen square reinforced concrete columns (150 mm × 150 mm × 600 mm) and one group of three circular columns ( φ 170 mm) that have cross-sectional areas equivalent to those of the square columns were cast from normal-strength concrete. The test program was designed to examine the behavior of columns strengthened by carbon fiber-reinforced polymer (CFRP), steel jacketing, ferro cement, steel fibers, and silica fumes under cyclic axial compression. The efficiency of each strengthening method in increasing the column’s axial capacity, energy absorption, and ductility was studied using the experimental data. The test results showed that strengthening the columns could significantly enhance their load-carrying capacity and failure strains.
{"title":"Structural Behavior of RC Columns Improved by Different Strengthening Techniques","authors":"Shahzeb Tariq, L. A. Qureshi, B. Ali, M. Rashid","doi":"10.2478/sjce-2020-0020","DOIUrl":"https://doi.org/10.2478/sjce-2020-0020","url":null,"abstract":"Abstract Deficient or deteriorating reinforced-concrete columns in many existing structures have to be strengthened using economical, efficient, and fast methods. In the present study, different strengthening techniques to improve the load-carrying capacity of reinforced concrete (RC) columns have been compared. Five groups of fifteen square reinforced concrete columns (150 mm × 150 mm × 600 mm) and one group of three circular columns ( φ 170 mm) that have cross-sectional areas equivalent to those of the square columns were cast from normal-strength concrete. The test program was designed to examine the behavior of columns strengthened by carbon fiber-reinforced polymer (CFRP), steel jacketing, ferro cement, steel fibers, and silica fumes under cyclic axial compression. The efficiency of each strengthening method in increasing the column’s axial capacity, energy absorption, and ductility was studied using the experimental data. The test results showed that strengthening the columns could significantly enhance their load-carrying capacity and failure strains.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"20 - 28"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48558006","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}
Abstract Results from medical research show that the use of domestic gas stoves could have a major impact on human health and well-being, especially if they used for heating. Approximately 0.289 m3 of natural gas is combusted daily in Hungarian kitchens. The users normally stand near the stove during its operation, which on average is 45 minutes long; therefore, they are directly affected by the combustion products. Nevertheless, uncertainties remain concerning the effects of the combustion products on humans; the nitrogen dioxide load could be the most problematic. Its nominal source strength is in a range of 12.0 - 21.0 ug/kJ, depending on the type of burner. In order to improve kitchen ventilation, a source model of domestic gas stoves has been developed that is based on measurement results, statistical data, and further technical assumptions.
{"title":"Source Model of Domestic Gas Stoves","authors":"Anita Leitner, L. Kajtár","doi":"10.2478/sjce-2020-0017","DOIUrl":"https://doi.org/10.2478/sjce-2020-0017","url":null,"abstract":"Abstract Results from medical research show that the use of domestic gas stoves could have a major impact on human health and well-being, especially if they used for heating. Approximately 0.289 m3 of natural gas is combusted daily in Hungarian kitchens. The users normally stand near the stove during its operation, which on average is 45 minutes long; therefore, they are directly affected by the combustion products. Nevertheless, uncertainties remain concerning the effects of the combustion products on humans; the nitrogen dioxide load could be the most problematic. Its nominal source strength is in a range of 12.0 - 21.0 ug/kJ, depending on the type of burner. In order to improve kitchen ventilation, a source model of domestic gas stoves has been developed that is based on measurement results, statistical data, and further technical assumptions.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"1 - 7"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41695590","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}
Abstract This paper deals with the sorption characteristics of thermal insulation materials based on flax and hemp. The added value of these materials is a positive impact on healthy and sustainable housing. Flax and hemp, which are classified as organic, have a high sorption capacity. Changes in the properties of these materials at a relative air humidity of 20% – 95% allow us to determine their advantages and disadvantages as well as whether the insulation is suitable for incorporation into a building structure. The article describes an experiment during which hygroscopic and thermal-technical properties were monitored. The most important indicators were the change in the coefficient of thermal conductivity and the change in the equilibrium moisture content.
{"title":"Sorption Properties of Thermal Insulation Composed of Flax or Hemp Fibers","authors":"K. Hellová, S. Unčík, T. Cabanová","doi":"10.2478/sjce-2020-0023","DOIUrl":"https://doi.org/10.2478/sjce-2020-0023","url":null,"abstract":"Abstract This paper deals with the sorption characteristics of thermal insulation materials based on flax and hemp. The added value of these materials is a positive impact on healthy and sustainable housing. Flax and hemp, which are classified as organic, have a high sorption capacity. Changes in the properties of these materials at a relative air humidity of 20% – 95% allow us to determine their advantages and disadvantages as well as whether the insulation is suitable for incorporation into a building structure. The article describes an experiment during which hygroscopic and thermal-technical properties were monitored. The most important indicators were the change in the coefficient of thermal conductivity and the change in the equilibrium moisture content.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"47 - 52"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43927720","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}
M. Savytskyi, S. Unčík, Olexandr Bardakh, A. Savytskyi, T. Shevchenko, O. Savytskyi
Abstract There are large amounts of reinforced concrete structures that have undergone damage from corrosion at their operational stage. The Eurocodes and national standards do not contain any guidelines for designing primary protection and repair systems for reinforced concrete structures. Our research shows the economic feasibility of designing reinforced concrete structures that can interact with an aggressive environment, taking into account the kinetics of concrete corrosion. Optimal design methods can be used to obtain the most economical solutions. We have developed a quantitative methodology for the design of the primary protection of reinforced concrete structures.
{"title":"Quantitative Design Methods for Protection Against Corrosion of Reinforced Concrete Structures During Various Stages of their Life Cycle","authors":"M. Savytskyi, S. Unčík, Olexandr Bardakh, A. Savytskyi, T. Shevchenko, O. Savytskyi","doi":"10.2478/sjce-2020-0018","DOIUrl":"https://doi.org/10.2478/sjce-2020-0018","url":null,"abstract":"Abstract There are large amounts of reinforced concrete structures that have undergone damage from corrosion at their operational stage. The Eurocodes and national standards do not contain any guidelines for designing primary protection and repair systems for reinforced concrete structures. Our research shows the economic feasibility of designing reinforced concrete structures that can interact with an aggressive environment, taking into account the kinetics of concrete corrosion. Optimal design methods can be used to obtain the most economical solutions. We have developed a quantitative methodology for the design of the primary protection of reinforced concrete structures.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"8 - 12"},"PeriodicalIF":0.4,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68917212","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}
G. Wurzer, U. Pont, W. Lorenz, Sigrun Swoboda, A. Mahdavi
Abstract The prediction of microclimate effects within an urban context through simulations has previously been done through elaborate software packages that offer accurate results but require extensive domain knowledge and time for the preparation of a model. In day-to-day policymaking, however, these efforts may turn out to be a major limiting factor: Policymakers and city administrators need a quick tool that can predict the effects of urban interventions in a variety of possible scenarios rather than a full-fledged simulation study for a limited set of specific interventions. In our work, we have been seeking to address this mismatch in expectations by using the best of both worlds: We have approximated results from a full-fledged simulation that uses a Cellular Automaton running within a 3D city visualization. Policymakers can edit the urban context by changing cell types (placement of greenery, etc.), thus leading to scenarios that can be compared to the status quo. As a matter of fact, policymakers can use these comparisons to argue for measures that mitigate the effects of heat islands, without requiring extensive domain knowledge or the effort to prepare a simulation model.
{"title":"A Web-Based 3D Simulation Platform Aimed at Policy Makers for Estimating the Effects of Urban Heat Islands","authors":"G. Wurzer, U. Pont, W. Lorenz, Sigrun Swoboda, A. Mahdavi","doi":"10.2478/sjce-2020-0010","DOIUrl":"https://doi.org/10.2478/sjce-2020-0010","url":null,"abstract":"Abstract The prediction of microclimate effects within an urban context through simulations has previously been done through elaborate software packages that offer accurate results but require extensive domain knowledge and time for the preparation of a model. In day-to-day policymaking, however, these efforts may turn out to be a major limiting factor: Policymakers and city administrators need a quick tool that can predict the effects of urban interventions in a variety of possible scenarios rather than a full-fledged simulation study for a limited set of specific interventions. In our work, we have been seeking to address this mismatch in expectations by using the best of both worlds: We have approximated results from a full-fledged simulation that uses a Cellular Automaton running within a 3D city visualization. Policymakers can edit the urban context by changing cell types (placement of greenery, etc.), thus leading to scenarios that can be compared to the status quo. As a matter of fact, policymakers can use these comparisons to argue for measures that mitigate the effects of heat islands, without requiring extensive domain knowledge or the effort to prepare a simulation model.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"18 - 22"},"PeriodicalIF":0.4,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43572710","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}
Abstract Understanding the brittleness of rock has a crucial importance in rock engineering applications such as the mechanical excavation of rock. In this study, numerical modeling of a punch penetration test is performed using the Discrete Element Method (DEM). The Peak Strength Index (PSI) as a function of the brittleness index was calculated using the axial load and a penetration graph obtained from numerical models. In the first step, the numerical model was verified by experimental results. The results obtained from the numerical modeling showed a good agreement with those obtained from the experimental tests. The propagation path was also simulated using Voronoi meshing. The fracture was created under the indenter in the first step, and then radial fractures were propagated. The effects of confining pressure and strength parameters on the PSI were subsequently investigated. The numerical results showed that the PSI increases with enhancing the confining pressure and the strength parameter of the rock, including cohesion and the friction angle. A new relationship between the strength parameters and PSI was also introduced based on two variable regressions of the numerical results.
{"title":"Numerical Modeling of a Punch Penetration Test Using the Discrete Element Method","authors":"R. Basirat, J. Hamidi","doi":"10.2478/sjce-2020-0008","DOIUrl":"https://doi.org/10.2478/sjce-2020-0008","url":null,"abstract":"Abstract Understanding the brittleness of rock has a crucial importance in rock engineering applications such as the mechanical excavation of rock. In this study, numerical modeling of a punch penetration test is performed using the Discrete Element Method (DEM). The Peak Strength Index (PSI) as a function of the brittleness index was calculated using the axial load and a penetration graph obtained from numerical models. In the first step, the numerical model was verified by experimental results. The results obtained from the numerical modeling showed a good agreement with those obtained from the experimental tests. The propagation path was also simulated using Voronoi meshing. The fracture was created under the indenter in the first step, and then radial fractures were propagated. The effects of confining pressure and strength parameters on the PSI were subsequently investigated. The numerical results showed that the PSI increases with enhancing the confining pressure and the strength parameter of the rock, including cohesion and the friction angle. A new relationship between the strength parameters and PSI was also introduced based on two variable regressions of the numerical results.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":" ","pages":"1 - 7"},"PeriodicalIF":0.4,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42677574","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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