Abstract The interference effects on the distribution of external wind pressure coefficient between two high-rise buildings with an elliptical cross section were studied experimentally at the Boundary Layer Wind Tunnel (BLWT) at the Faculty of Civil Engineering STU in Bratislava, Slovakia. Various arrangements of models, which were derived from the breadth ratio, were investigated. The peak value of the external wind pressure coefficient for a stand-alone model was measured and compared with the peak value in the case of interference. The measurements showed that the wind loads on buildings in a close vicinity are considerably different from those on a stand-alone building. The interference effects significantly affect negative pressure zones. The optimal and critical arrangements of buildings were evaluated. The elimination of peak negative external wind pressure coefficients can be reduced by half. On the other hand, the interference effects had a strong impact on increasing the peak value of the negative external wind pressure coefficient, which can be more than roughly double compared to an isolated building.
{"title":"Effects of Interference on Local Peak Pressures Between Two Buildings with an Elliptical Cross-Section","authors":"M. Franek, M. Macák","doi":"10.2478/sjce-2021-0006","DOIUrl":"https://doi.org/10.2478/sjce-2021-0006","url":null,"abstract":"Abstract The interference effects on the distribution of external wind pressure coefficient between two high-rise buildings with an elliptical cross section were studied experimentally at the Boundary Layer Wind Tunnel (BLWT) at the Faculty of Civil Engineering STU in Bratislava, Slovakia. Various arrangements of models, which were derived from the breadth ratio, were investigated. The peak value of the external wind pressure coefficient for a stand-alone model was measured and compared with the peak value in the case of interference. The measurements showed that the wind loads on buildings in a close vicinity are considerably different from those on a stand-alone building. The interference effects significantly affect negative pressure zones. The optimal and critical arrangements of buildings were evaluated. The elimination of peak negative external wind pressure coefficients can be reduced by half. On the other hand, the interference effects had a strong impact on increasing the peak value of the negative external wind pressure coefficient, which can be more than roughly double compared to an isolated building.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"29 1","pages":"35 - 41"},"PeriodicalIF":0.4,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48747852","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 The article is devoted to a study of the impact of various environmental conditions on modal parameters, such as natural frequencies and damping ratios. The modal analysis has been performed using the Stochastic Subspace Identification (SSI) method of measuring data every month on the same steel bridge structures located on an important railroad route from Prague (the Czech Republic) to Košice (Slovakia). The structure is approximately 60 m long, and the bearing structure is formed by two arch trusses. The bridge was exposed to ambient vibrations as well as to vibrations caused by a train passage. Accelerations and temperatures (the temperature of the air and the structure) were logged during the measurements. Natural frequencies were obtained from these acceleration data using the SSI method and processed into graphs of the dependencies between the natural frequencies and temperatures. Some statistical procedures were also applied.
{"title":"Effect of the Temperature on the Modal Properties of a Steel Railroad Bridge","authors":"M. Venglár, K. Lamperová","doi":"10.2478/sjce-2021-0001","DOIUrl":"https://doi.org/10.2478/sjce-2021-0001","url":null,"abstract":"Abstract The article is devoted to a study of the impact of various environmental conditions on modal parameters, such as natural frequencies and damping ratios. The modal analysis has been performed using the Stochastic Subspace Identification (SSI) method of measuring data every month on the same steel bridge structures located on an important railroad route from Prague (the Czech Republic) to Košice (Slovakia). The structure is approximately 60 m long, and the bearing structure is formed by two arch trusses. The bridge was exposed to ambient vibrations as well as to vibrations caused by a train passage. Accelerations and temperatures (the temperature of the air and the structure) were logged during the measurements. Natural frequencies were obtained from these acceleration data using the SSI method and processed into graphs of the dependencies between the natural frequencies and temperatures. Some statistical procedures were also applied.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":" ","pages":"1 - 8"},"PeriodicalIF":0.4,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48572139","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 The aim of this work was to analyze and statistically confirm the relationship between the computed daily values of the Effective Precipitation Index (EP365) and the measured moisture content of the topsoil of a research site near Nitra, Slovakia. The statistical analysis (coefficients of determination) confirmed the strong correlation. Subsequently each day’s mean of EP365 (MEP) was used to quantify the long-term deficit or surplus of the soil water supply in the individual years. The daily values of the EP365 index provide a more detailed view of the development of the topsoil’s moisture regime. According to the deviation of EP (DEP) from the 14-year MEP, the most extreme dry periods prevailed during the years 2015, 2017 and 2018. Therefore, the 2012–2018period was evaluated as dry, and the topsoil moisture regime described through the MEP index was compared with the course of the MEP index from the normal (slightly humid) period of the years 2005 – 2011.
{"title":"Analysis of a Topsoil Moisture Regime Through an Effective Precipitation Index for the Locality of Nitra, Slovakia","authors":"P. Rončák, P. Šurda, J. Vitková","doi":"10.2478/sjce-2021-0002","DOIUrl":"https://doi.org/10.2478/sjce-2021-0002","url":null,"abstract":"Abstract The aim of this work was to analyze and statistically confirm the relationship between the computed daily values of the Effective Precipitation Index (EP365) and the measured moisture content of the topsoil of a research site near Nitra, Slovakia. The statistical analysis (coefficients of determination) confirmed the strong correlation. Subsequently each day’s mean of EP365 (MEP) was used to quantify the long-term deficit or surplus of the soil water supply in the individual years. The daily values of the EP365 index provide a more detailed view of the development of the topsoil’s moisture regime. According to the deviation of EP (DEP) from the 14-year MEP, the most extreme dry periods prevailed during the years 2015, 2017 and 2018. Therefore, the 2012–2018period was evaluated as dry, and the topsoil moisture regime described through the MEP index was compared with the course of the MEP index from the normal (slightly humid) period of the years 2005 – 2011.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":" ","pages":"9 - 14"},"PeriodicalIF":0.4,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46687685","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}
B. Varaprasad, Jayaprakash Reddy Joga, Suryaprakash Reddy Joga
Abstract A useful method for the disposal of waste from an incineration plant is to reuse it for geotechnical and civil engineering applications. The primary objective of this study concerns the reuse of local incinerated ash from municipal solid wastes in soil stabilization. Municipal Solid Waste Incinerated Ash (MSWIA) is blended with soil in various combinations and tested for its Atterberg limits, unconfined compressive strength (UCS), California Bearing Ratio (CBR), and Free Swell Index (FSI). A 1-D Consolidation Test was conducted, and changes in the soil during the test were examined by a scanning electron microscopic (SEM) analysis. The test results showed that there are increments in the UCS and CBR values with the reductions in the FSI, swell pressure, and swell potential of the treated soils.
{"title":"Reuse of Municipal Solid Waste from Incinerated Ash in the Stabilization of Clayey Soils","authors":"B. Varaprasad, Jayaprakash Reddy Joga, Suryaprakash Reddy Joga","doi":"10.2478/sjce-2020-0024","DOIUrl":"https://doi.org/10.2478/sjce-2020-0024","url":null,"abstract":"Abstract A useful method for the disposal of waste from an incineration plant is to reuse it for geotechnical and civil engineering applications. The primary objective of this study concerns the reuse of local incinerated ash from municipal solid wastes in soil stabilization. Municipal Solid Waste Incinerated Ash (MSWIA) is blended with soil in various combinations and tested for its Atterberg limits, unconfined compressive strength (UCS), California Bearing Ratio (CBR), and Free Swell Index (FSI). A 1-D Consolidation Test was conducted, and changes in the soil during the test were examined by a scanning electron microscopic (SEM) analysis. The test results showed that there are increments in the UCS and CBR values with the reductions in the FSI, swell pressure, and swell potential of the treated soils.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":" ","pages":"1 - 7"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45467127","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 Concrete hinges can withstand extremely high loads and rotations, while requiring only minimal maintenance. Their use is widespread, mainly in bridge construction, but they also find applications in the prefabrication of tunnel segments. With the right design and implementation, they can meet the highest requirements for the durability and resistance of a structure. However, the existing models and design procedures are relatively outdated. The models are based solely on empirical assumptions, whereas the shear resistance of the joint itself plays only a marginal role. The following paper aims to compare existing design models against experimental results in order to find the most suitable design approach that reliably captures the performance of a hinge under a shear load. An experimental program was developed in which 9 samples of concrete hinges were tested for different levels of axial loads and degrees of reinforcement. The results of the experiments were then compared with the selected design models, and a numerical nonlinear analysis was conducted.
{"title":"Experimental Investigation of the Shear Resistance of Concrete Hinges Under a Biaxial Load","authors":"P. Havlíček, J. Šoltész, J. Gašpárek","doi":"10.2478/sjce-2020-0031","DOIUrl":"https://doi.org/10.2478/sjce-2020-0031","url":null,"abstract":"Abstract Concrete hinges can withstand extremely high loads and rotations, while requiring only minimal maintenance. Their use is widespread, mainly in bridge construction, but they also find applications in the prefabrication of tunnel segments. With the right design and implementation, they can meet the highest requirements for the durability and resistance of a structure. However, the existing models and design procedures are relatively outdated. The models are based solely on empirical assumptions, whereas the shear resistance of the joint itself plays only a marginal role. The following paper aims to compare existing design models against experimental results in order to find the most suitable design approach that reliably captures the performance of a hinge under a shear load. An experimental program was developed in which 9 samples of concrete hinges were tested for different levels of axial loads and degrees of reinforcement. The results of the experiments were then compared with the selected design models, and a numerical nonlinear analysis was conducted.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"52 - 59"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45852742","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}
A. Życzyńska, Z. Suchorab, G. Dyś, J. Čurpek, M. Čekon
Abstract The paper presents the structure and indices of the annual energy consumption in educational buildings subject to comprehensive thermal retrofitting. Seven buildings were analyzed; the energy consumption for heating and ventilation, hot water preparation, and built-in lighting was analyzed in each of them and, in the case of one structure, also cooling. The indices of the usable, final, and primary energy consumption were analyzed. The values calculated were compared to the requirements of the energy standards in force in Poland. The percentage shares of the above-mentioned energy demands of each of the buildings investigated are given in the total energy performance. Within the investigation, we evaluated the shares of the particular building services in the total energy consumption and determined that even after the thermal retrofitting, the energy demands for heating together with lighting are still the most significant compared to the other demands.
{"title":"An Evaluation of the Structure of Energy Consumption in Educational Buildings in Poland After Thermal Retrofitting","authors":"A. Życzyńska, Z. Suchorab, G. Dyś, J. Čurpek, M. Čekon","doi":"10.2478/sjce-2020-0028","DOIUrl":"https://doi.org/10.2478/sjce-2020-0028","url":null,"abstract":"Abstract The paper presents the structure and indices of the annual energy consumption in educational buildings subject to comprehensive thermal retrofitting. Seven buildings were analyzed; the energy consumption for heating and ventilation, hot water preparation, and built-in lighting was analyzed in each of them and, in the case of one structure, also cooling. The indices of the usable, final, and primary energy consumption were analyzed. The values calculated were compared to the requirements of the energy standards in force in Poland. The percentage shares of the above-mentioned energy demands of each of the buildings investigated are given in the total energy performance. Within the investigation, we evaluated the shares of the particular building services in the total energy consumption and determined that even after the thermal retrofitting, the energy demands for heating together with lighting are still the most significant compared to the other demands.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"29 - 37"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41861197","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 article focuses on 3D printing of buildings using cement mortar-based material. Specific requirements are necessary for such a material; it therefore must have different properties compared to conventional cement mortar. These properties of a fresh mixture and the possibilities for their testing are described in more detail in the first part of the article. Specifically, these are pumpability, printability, buildability, and workability. In order to achieve these properties, it is necessary to add various additives and admixtures to the mixtures, in addition to the basic components such as water, sand, and cement. Scientists around the world are working to create an optimal mix. The second part of this article presents an overview of the most commonly used ingredients and their effect on the properties of the mixture.
{"title":"Specification of the Properties and Effects of Additives and Admixtures on a Mixture Suitable for 3D Printing of Buildings","authors":"Diana Fiľarská, S. Unčík, T. Cabanová","doi":"10.2478/sjce-2020-0029","DOIUrl":"https://doi.org/10.2478/sjce-2020-0029","url":null,"abstract":"Abstract This article focuses on 3D printing of buildings using cement mortar-based material. Specific requirements are necessary for such a material; it therefore must have different properties compared to conventional cement mortar. These properties of a fresh mixture and the possibilities for their testing are described in more detail in the first part of the article. Specifically, these are pumpability, printability, buildability, and workability. In order to achieve these properties, it is necessary to add various additives and admixtures to the mixtures, in addition to the basic components such as water, sand, and cement. Scientists around the world are working to create an optimal mix. The second part of this article presents an overview of the most commonly used ingredients and their effect on the properties of the mixture.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"38 - 44"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44177477","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}
Oleksandra Kuzmenko, K. Dikarev, D. Rodionov, O. Martysh, A. Iskenderov, M. Babenko
Abstract To ensure low-energy consumption in new generation energy-efficient houses, the technology of a ground heat exchanger with a heat recovery system is used almost everywhere. However, this technology has not been widely disseminated in Ukraine. The work is aimed at presenting insights from research on the combination of ground heat exchangers with a heat recovery system for building ventilation by analyzing the operational and techno-economic indicators obtained. Current studies permit revealing the optimal configuration of a ground heat exchanger with a heat recovery system for ventilation in a residential building in order to analyze the efficiency of ground heat exchangers with a heat recovery system for ventilation of a residential building in comparison with several conventional ventilation options to assess the main price/ performance ration of the process of constructing a ground heat exchanger with a heat recovery system and to determine the duration of the technological process, the labor-intensive characteristics, and the estimated cost of the technology.
{"title":"Geothermal Energy Use for the Additional Heat Supply of a Residential Building","authors":"Oleksandra Kuzmenko, K. Dikarev, D. Rodionov, O. Martysh, A. Iskenderov, M. Babenko","doi":"10.2478/sjce-2020-0026","DOIUrl":"https://doi.org/10.2478/sjce-2020-0026","url":null,"abstract":"Abstract To ensure low-energy consumption in new generation energy-efficient houses, the technology of a ground heat exchanger with a heat recovery system is used almost everywhere. However, this technology has not been widely disseminated in Ukraine. The work is aimed at presenting insights from research on the combination of ground heat exchangers with a heat recovery system for building ventilation by analyzing the operational and techno-economic indicators obtained. Current studies permit revealing the optimal configuration of a ground heat exchanger with a heat recovery system for ventilation in a residential building in order to analyze the efficiency of ground heat exchangers with a heat recovery system for ventilation of a residential building in comparison with several conventional ventilation options to assess the main price/ performance ration of the process of constructing a ground heat exchanger with a heat recovery system and to determine the duration of the technological process, the labor-intensive characteristics, and the estimated cost of the technology.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"15 - 22"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47330501","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 The aim of this article is to point out the potential of urban spaces that have not been primarily meant to be barefoot parks. The stimulation of bare feet is used as a part of therapy or for the prevention of plantar problems. The high number of research papers or blogs available about bare feet shows the interest in this topic among scientists, doctors and the broader population. People are usually shod in a city environment. An analysis of some existing barefoot/sensomotoric spaces compares 3 different projects located in Italy, Germany, and Colombia. The paper shows the common and different approaches in information systems and the amount, variability, and spatial arrangement of stimulation surfaces of these projects. The same method of categorization is used in the analysis of a newly reconstructed park in Slovakia, which was built without a request for a barefoot space. A comparison of these analyses shows the high potential for a regular park having a barefoot area. This research proves that barefoot places in urban areas could be instituted without any significant financial or construction interventions.
{"title":"Stimulation Surfaces in Urban Places","authors":"M. Majorošová, E. Mazancová","doi":"10.2478/sjce-2020-0030","DOIUrl":"https://doi.org/10.2478/sjce-2020-0030","url":null,"abstract":"Abstract The aim of this article is to point out the potential of urban spaces that have not been primarily meant to be barefoot parks. The stimulation of bare feet is used as a part of therapy or for the prevention of plantar problems. The high number of research papers or blogs available about bare feet shows the interest in this topic among scientists, doctors and the broader population. People are usually shod in a city environment. An analysis of some existing barefoot/sensomotoric spaces compares 3 different projects located in Italy, Germany, and Colombia. The paper shows the common and different approaches in information systems and the amount, variability, and spatial arrangement of stimulation surfaces of these projects. The same method of categorization is used in the analysis of a newly reconstructed park in Slovakia, which was built without a request for a barefoot space. A comparison of these analyses shows the high potential for a regular park having a barefoot area. This research proves that barefoot places in urban areas could be instituted without any significant financial or construction interventions.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"45 - 51"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48113103","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}
Marek Braniš, Matej Šulík, J. Takacs, T. Schlosser
Abstract With the current worldwide trend of increasing individual car traffic in urban road networks, public transport has become one of the key issues for the sustainable future of transport in cities, especially when the level of automobilization is growing rapidly. Many cities are already at the capacity limit of an existing road network. Therefore, many cities are trying to solve the question of how to improve the existing systems of public transport to become more attractive for their citizens. The quality of the public transport service from a passenger’s point of view is not only about the number of links and their occupancy, but also about the time and distance availability of stops and stations. When we were creating the general master plan for one small Slovak town, we tried to take various criteria into account. Of course, it was also necessary to carry out traffic surveys to determine the occupancy of public transport systems, but equally important was to determine the isochrones and isodistances of the passengers. The lessons learned and complications that arose from the preparation and realization of the actual analysis of the results in the creation of the general master plan are set out in the contribution.
{"title":"Analysis of Public Transport Services with Various Criteria","authors":"Marek Braniš, Matej Šulík, J. Takacs, T. Schlosser","doi":"10.2478/sjce-2020-0027","DOIUrl":"https://doi.org/10.2478/sjce-2020-0027","url":null,"abstract":"Abstract With the current worldwide trend of increasing individual car traffic in urban road networks, public transport has become one of the key issues for the sustainable future of transport in cities, especially when the level of automobilization is growing rapidly. Many cities are already at the capacity limit of an existing road network. Therefore, many cities are trying to solve the question of how to improve the existing systems of public transport to become more attractive for their citizens. The quality of the public transport service from a passenger’s point of view is not only about the number of links and their occupancy, but also about the time and distance availability of stops and stations. When we were creating the general master plan for one small Slovak town, we tried to take various criteria into account. Of course, it was also necessary to carry out traffic surveys to determine the occupancy of public transport systems, but equally important was to determine the isochrones and isodistances of the passengers. The lessons learned and complications that arose from the preparation and realization of the actual analysis of the results in the creation of the general master plan are set out in the contribution.","PeriodicalId":43574,"journal":{"name":"Slovak Journal of Civil Engineering","volume":"28 1","pages":"23 - 28"},"PeriodicalIF":0.4,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45727697","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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