Sangketa Sangma, D. Tripura, Arpan Deshmukh, Ayub Shaikh
This paper deals with the validation of cob sample production technique that replicates the on-site wall construction method. Cob cubes were prepared under confined and unconfined conditions with varying drop heights (0.50 m, 0.75 m and 1.0 m) and moulding water content (25.7% to 39.7%) by mass of soil. Prior to mass production of samples, a trial test was performed at a constant drop height of 0.75 m and varying water content. Based on the trial test results, other two drop heights of 0.50 m and 1.0 m were adopted for further validation. The effect of confinement, drop heights and moulding water content on compressive strength and density of cubes were studied. Test result shows maximum compressive strength and density ranging from 1.22 MPa to 1.31 MPa and 1.65 g/cc to 1.70 g/cc respectively at 33.7% water content and 0.75 m drop height with confined specimen being the highest. The strength and density values obtained satisfy the guidelines prescribed by some of the standards. Thus, the proposed technique for cob production may be adopted to achieve the desirable compressive strength and density for the particular soil used in the present study.
{"title":"A study on cob sample production and techniques","authors":"Sangketa Sangma, D. Tripura, Arpan Deshmukh, Ayub Shaikh","doi":"10.1680/jfoen.22.00022","DOIUrl":"https://doi.org/10.1680/jfoen.22.00022","url":null,"abstract":"This paper deals with the validation of cob sample production technique that replicates the on-site wall construction method. Cob cubes were prepared under confined and unconfined conditions with varying drop heights (0.50 m, 0.75 m and 1.0 m) and moulding water content (25.7% to 39.7%) by mass of soil. Prior to mass production of samples, a trial test was performed at a constant drop height of 0.75 m and varying water content. Based on the trial test results, other two drop heights of 0.50 m and 1.0 m were adopted for further validation. The effect of confinement, drop heights and moulding water content on compressive strength and density of cubes were studied. Test result shows maximum compressive strength and density ranging from 1.22 MPa to 1.31 MPa and 1.65 g/cc to 1.70 g/cc respectively at 33.7% water content and 0.75 m drop height with confined specimen being the highest. The strength and density values obtained satisfy the guidelines prescribed by some of the standards. Thus, the proposed technique for cob production may be adopted to achieve the desirable compressive strength and density for the particular soil used in the present study.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89224283","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}
In this study, the essential aim is to produce an environment-friendly ferrocement mortar using different waste internal curing materials and external curing methods. Wastes of broken bricks and porcelanite were used with different volumetric replacement percentages (5%, 10%, and 15 %) of fine aggregate. Moreover, pozzolanic materials (silica fume and fly ash) were used. In addition to the water-cured reference mixture, four different curing methods (air, flan coat emulsified asphalt, wax sealing paint, and carbon dioxide gas (CO2)) were used. Compressive, flexural strength, and density for different ages of mortar (7, 14, and 28 d) were investigated. The outcomes demonstrate that, compressive strength of CO2-cured ferrocement improved by 33.3% and 28% when 5% and 10% of broken bricks was used and by 25.3% and 29% when 5% and 10% of porcelanite was used, respectively, than when the reference was used. The flexural strength was slightly improved when 10% porcelanite was used. Results demonstrate that the outcome ferrocement mortar was improved in spite of using different waste materials in production.
{"title":"Sustainable ferrocement mortar with different waste materials and curing methods","authors":"Z. Abed, H. Jaber, Esra’a lutfi Ibrahim","doi":"10.1680/jfoen.22.00014","DOIUrl":"https://doi.org/10.1680/jfoen.22.00014","url":null,"abstract":"In this study, the essential aim is to produce an environment-friendly ferrocement mortar using different waste internal curing materials and external curing methods. Wastes of broken bricks and porcelanite were used with different volumetric replacement percentages (5%, 10%, and 15 %) of fine aggregate. Moreover, pozzolanic materials (silica fume and fly ash) were used. In addition to the water-cured reference mixture, four different curing methods (air, flan coat emulsified asphalt, wax sealing paint, and carbon dioxide gas (CO2)) were used. Compressive, flexural strength, and density for different ages of mortar (7, 14, and 28 d) were investigated. The outcomes demonstrate that, compressive strength of CO2-cured ferrocement improved by 33.3% and 28% when 5% and 10% of broken bricks was used and by 25.3% and 29% when 5% and 10% of porcelanite was used, respectively, than when the reference was used. The flexural strength was slightly improved when 10% porcelanite was used. Results demonstrate that the outcome ferrocement mortar was improved in spite of using different waste materials in production.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86929393","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}
Design review is an important aspect of engineering design. Designs certified by a professional engineer require some form of external check. This external check can range from a quick intuitive assessment of a proposed solution to a reassessment of the problem using alternative methods. This research explored intuitive review assessments for two typical geotechnical designs. Results suggest that those with requisite experience (even seemingly little experience) can make correct assessments even after spending as few as 4 minutes reviewing a carefully presented solution. Forcing participants to state reasons for a decision (and thereby slowing them down) only served to improve predictions by novices attempting an unfamiliar problem. While such quick intuitive reviews appeared adequate for assessing the problems presented here, some experts still made erroneous decisions even after stating reasons for a decision. Design reviews are an important step in design and should never be taken lightly.
{"title":"Design reviewing: are experts better and does slowing down improve performance?","authors":"C. MacRobert","doi":"10.1680/jfoen.22.00013","DOIUrl":"https://doi.org/10.1680/jfoen.22.00013","url":null,"abstract":"Design review is an important aspect of engineering design. Designs certified by a professional engineer require some form of external check. This external check can range from a quick intuitive assessment of a proposed solution to a reassessment of the problem using alternative methods. This research explored intuitive review assessments for two typical geotechnical designs. Results suggest that those with requisite experience (even seemingly little experience) can make correct assessments even after spending as few as 4 minutes reviewing a carefully presented solution. Forcing participants to state reasons for a decision (and thereby slowing them down) only served to improve predictions by novices attempting an unfamiliar problem. While such quick intuitive reviews appeared adequate for assessing the problems presented here, some experts still made erroneous decisions even after stating reasons for a decision. Design reviews are an important step in design and should never be taken lightly.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78272843","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}
The Aso Bridge is located near the Futagawa Fault, which is considered to be the epicenter fault of the Kumamoto Earthquake. This paper presents the technical findings obtained through the investigation and design of the Aso Ohashi Bridge replacement project after the Kumamoto Earthquake, including ① extraction of active fault zones ② evaluation of fault activity found on the cut slope, and ③ stability evaluation of the excavated surface behind the bridge piers considering the mechanical properties of columnar joints.
{"title":"Active Fault investigation and slope stability evaluation for the Aso Bridge replacement","authors":"Koji Yamashita, Shingo Tanaka, Takefumi Yamaguchi","doi":"10.1680/jfoen.21.00003","DOIUrl":"https://doi.org/10.1680/jfoen.21.00003","url":null,"abstract":"The Aso Bridge is located near the Futagawa Fault, which is considered to be the epicenter fault of the Kumamoto Earthquake. This paper presents the technical findings obtained through the investigation and design of the Aso Ohashi Bridge replacement project after the Kumamoto Earthquake, including ① extraction of active fault zones ② evaluation of fault activity found on the cut slope, and ③ stability evaluation of the excavated surface behind the bridge piers considering the mechanical properties of columnar joints.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84406754","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}
Many engineers act as expert witnesses or are considering taking on some expert witness work. This paper provides guidance on the current civil court rules that are relevant to engineers writing expert witness reports and giving expert evidence in civil claims, to assist engineers in complying with the civil court rules applicable to experts.
{"title":"Briefing: Compliance with the rules of court as an expert witness","authors":"Sarah Saunders","doi":"10.1680/jfoen.22.00016","DOIUrl":"https://doi.org/10.1680/jfoen.22.00016","url":null,"abstract":"Many engineers act as expert witnesses or are considering taking on some expert witness work. This paper provides guidance on the current civil court rules that are relevant to engineers writing expert witness reports and giving expert evidence in civil claims, to assist engineers in complying with the civil court rules applicable to experts.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91366578","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}
Mamoona Riaz, Z. Alam, T. Zafar, U. Javed, Hanzlah Akhlaq
The surge in production of cement due to rapid growth of construction industry has an adverse effect on environment globally caused by the huge amount of carbon emission. In order to produce an environment friendly concrete, this study investigates the effective contribution of silica fume (SF) on various mechanical and durability characteristics of high strength concrete. In this regard, the incorporation of silica fume was adopted with a progressive proportion of 0%, 5%, 10%, 15%, 20%, 25% and 30% by weight of cement constituting various concrete mixes namely CM, SF05, SF10, SF15, SF20, SF25 and SF30 respectively. The mechanical and durability properties of concrete improved along with the incorporation of SF up to its 15% replacement. However, excessive replacement of SF have adverse effect on its mechanical and durability properties due to dilution effect of cement. Similarly, in terms of the mechanical characteristics, the proposed 15% substitution of silica fume resulted in highest compressive and flexural strengths with respect to CM. The maximum reduction in strength loss with respect to control mix was 41.17% and 28.04% for sulfuric and hydrochloric acid due to formation of densified microstructure.
{"title":"Investigation of mechanical and durability properties of sustainable high-strength concrete","authors":"Mamoona Riaz, Z. Alam, T. Zafar, U. Javed, Hanzlah Akhlaq","doi":"10.1680/jfoen.22.00008","DOIUrl":"https://doi.org/10.1680/jfoen.22.00008","url":null,"abstract":"The surge in production of cement due to rapid growth of construction industry has an adverse effect on environment globally caused by the huge amount of carbon emission. In order to produce an environment friendly concrete, this study investigates the effective contribution of silica fume (SF) on various mechanical and durability characteristics of high strength concrete. In this regard, the incorporation of silica fume was adopted with a progressive proportion of 0%, 5%, 10%, 15%, 20%, 25% and 30% by weight of cement constituting various concrete mixes namely CM, SF05, SF10, SF15, SF20, SF25 and SF30 respectively. The mechanical and durability properties of concrete improved along with the incorporation of SF up to its 15% replacement. However, excessive replacement of SF have adverse effect on its mechanical and durability properties due to dilution effect of cement. Similarly, in terms of the mechanical characteristics, the proposed 15% substitution of silica fume resulted in highest compressive and flexural strengths with respect to CM. The maximum reduction in strength loss with respect to control mix was 41.17% and 28.04% for sulfuric and hydrochloric acid due to formation of densified microstructure.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80815866","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}
The persistence of accidents, injuries and fatalities on construction sites is an ongoing concern. One of the factors that cause these negative events that are yet to be addressed widely is a safety violation, which is examined in this article. A phenomenological study was undertaken in the central region of South Africa among professionals who are active in construction. The collated textual data confirmed that unsafe worksites, negligence and fatigue, and intoxication are detrimental to safe operations during construction. Operational analysis and control is a process that can be used to help focus attention on the sources of safety violations while integrating all aspects of operational work in a way that does not harm people. The practical implication is that operational analysis and control can be deployed during various types of construction projects, including municipal engineering projects, with existing legislation and regulations.
{"title":"Operational analysis for controlling safety violations on construction sites","authors":"Fidelis Emuze","doi":"10.1680/jfoen.22.00015","DOIUrl":"https://doi.org/10.1680/jfoen.22.00015","url":null,"abstract":"The persistence of accidents, injuries and fatalities on construction sites is an ongoing concern. One of the factors that cause these negative events that are yet to be addressed widely is a safety violation, which is examined in this article. A phenomenological study was undertaken in the central region of South Africa among professionals who are active in construction. The collated textual data confirmed that unsafe worksites, negligence and fatigue, and intoxication are detrimental to safe operations during construction. Operational analysis and control is a process that can be used to help focus attention on the sources of safety violations while integrating all aspects of operational work in a way that does not harm people. The practical implication is that operational analysis and control can be deployed during various types of construction projects, including municipal engineering projects, with existing legislation and regulations.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83991186","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}
Muhammad Israr Khan, Shuhong Wang, Pengyu Wang, Mohammad Ajmal Nikjow
Shear strength (τ), shear stress (σs) and slope angle (β) plays a very important role in the stability of any soil slope. This research investigates the slope stability of a soil slope in order to determine correlations between shear strength with slope angle and shear stress. The assessment and calculation of the soil slope are carried out using slope stability analysis methods that assumed the failure surface as circular slip surface. A limit equilibrium software namely Slide and numerical modelling software namely Statistical Package for Social Sciences (SPSS) are used for the analysis. A total number of two hundred analysis are performed with varying slope angle of 70 to 88 degrees. Correlations are developed between τ, β and σs, which shows a very close relationship of all these three parameters. Applicability of the equations is above 97%. The correlations can be used in any slope stability project to know about the shear strength of the slope with variation in the value of slope angle and shear stress.
{"title":"Soil slope analysis to develop useful correlations in saturated and unsaturated conditions","authors":"Muhammad Israr Khan, Shuhong Wang, Pengyu Wang, Mohammad Ajmal Nikjow","doi":"10.1680/jfoen.22.00002","DOIUrl":"https://doi.org/10.1680/jfoen.22.00002","url":null,"abstract":"Shear strength (τ), shear stress (σs) and slope angle (β) plays a very important role in the stability of any soil slope. This research investigates the slope stability of a soil slope in order to determine correlations between shear strength with slope angle and shear stress. The assessment and calculation of the soil slope are carried out using slope stability analysis methods that assumed the failure surface as circular slip surface. A limit equilibrium software namely Slide and numerical modelling software namely Statistical Package for Social Sciences (SPSS) are used for the analysis. A total number of two hundred analysis are performed with varying slope angle of 70 to 88 degrees. Correlations are developed between τ, β and σs, which shows a very close relationship of all these three parameters. Applicability of the equations is above 97%. The correlations can be used in any slope stability project to know about the shear strength of the slope with variation in the value of slope angle and shear stress.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84440073","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}
The causes of cracks in 6-storey building are studied. Based on analyses of crack morphology, settlement observation and geological survey, it is determined that the landfill pit and uneven settlement is the main cause of cracks. The July 20th Zhengzhou Rainstorm caused a sharp rise of groundwater level, so that the uneven settlement of the office building near the landfill pit intensified, and then the wall cracking is followed. The interaction between buildings and landfill pits under different water levels is studied by three-dimensional numerical simulation. As the water level rise, the horizontal displacement of soil in the landfill pit increase, and the lateral constraint of landfill soil to foundation soil decrease, the result is that the settlement of column foundation near the landfill pits increases and the differential settlement intensifies. According to the analysis results, the further development of differential settlement and cracks are evaluated and the treatment suggestions are given.
{"title":"Case analysis of sudden cracking in buildings near landfill pit","authors":"Q. Zhang, Xiaoyong Xu, Qiang Zhao","doi":"10.1680/jfoen.22.00010","DOIUrl":"https://doi.org/10.1680/jfoen.22.00010","url":null,"abstract":"The causes of cracks in 6-storey building are studied. Based on analyses of crack morphology, settlement observation and geological survey, it is determined that the landfill pit and uneven settlement is the main cause of cracks. The July 20th Zhengzhou Rainstorm caused a sharp rise of groundwater level, so that the uneven settlement of the office building near the landfill pit intensified, and then the wall cracking is followed. The interaction between buildings and landfill pits under different water levels is studied by three-dimensional numerical simulation. As the water level rise, the horizontal displacement of soil in the landfill pit increase, and the lateral constraint of landfill soil to foundation soil decrease, the result is that the settlement of column foundation near the landfill pits increases and the differential settlement intensifies. According to the analysis results, the further development of differential settlement and cracks are evaluated and the treatment suggestions are given.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78438147","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}
One of the main principles of critical infrastructure resilience (CIR) is risk assessment for severe shocks caused by natural or man-made disasters. Vulnerability assessment plays an important role in calculating risk. One type of vulnerability assessment is the sequential-function vulnerability assessment, which is based on the network characteristics and interdependencies of different assets. A further significant area of vulnerability among resilient infrastructures relates to time. Time can change interdependencies, it can modify the inherent properties of individual assets, and it can superpose impacts through pathways between receptors and sources during each shock. This study aims to develop a new technique for assessing dynamic time-based vulnerability as a main factor in risk analysis for achieving resilience. In this study, a new analytical equation is developed based on the effect of the source and the interdependencies between the receptors as nodes in the infrastructure network. Direct and indirect impacts on each infrastructure receptor are simulated by impulse functions and Heaviside functions superposed in the total function. The equation for time-based vulnerability assessment for interdependent assets in critical infrastructures is obtained by employing a Laplace transformation. Finally, the developed equation is tested on a hypothetical case study to assess vulnerability.
{"title":"Dynamic time-based vulnerability assessment in pursuit of critical infrastructure resilience","authors":"M. A. Nekooie, Ghasem Taghizadeh","doi":"10.1680/jfoen.21.00033","DOIUrl":"https://doi.org/10.1680/jfoen.21.00033","url":null,"abstract":"One of the main principles of critical infrastructure resilience (CIR) is risk assessment for severe shocks caused by natural or man-made disasters. Vulnerability assessment plays an important role in calculating risk. One type of vulnerability assessment is the sequential-function vulnerability assessment, which is based on the network characteristics and interdependencies of different assets. A further significant area of vulnerability among resilient infrastructures relates to time. Time can change interdependencies, it can modify the inherent properties of individual assets, and it can superpose impacts through pathways between receptors and sources during each shock. This study aims to develop a new technique for assessing dynamic time-based vulnerability as a main factor in risk analysis for achieving resilience. In this study, a new analytical equation is developed based on the effect of the source and the interdependencies between the receptors as nodes in the infrastructure network. Direct and indirect impacts on each infrastructure receptor are simulated by impulse functions and Heaviside functions superposed in the total function. The equation for time-based vulnerability assessment for interdependent assets in critical infrastructures is obtained by employing a Laplace transformation. Finally, the developed equation is tested on a hypothetical case study to assess vulnerability.","PeriodicalId":42902,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Forensic Engineering","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81639447","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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