This paper proposes an analytical scheme for stability analysis in turning process by considering the motion of tailstock-supported workpiece using a compliance model of tool and work. A dynamic cutting force model based on relative motion between the cutting tool and workpiece is developed to study the chatter stability. Linear stability analysis is carried out in the frequency domain and the stability charts are obtained with and without considering workpiece flexibility. Variations of stability limits with workpiece dimensions and cutter position as well as the effects of cutting tool dynamics are studied and wherever possible results are compared with existing models. Experimental analysis is conducted on tailstock-supported workpiece to examine the correctness of the proposed stability model.
{"title":"Analysis of stability in Turning with Secondary effects","authors":"B.Tulasiramarao, K. Srinivas, P. R. Reddy","doi":"10.9790/1684-1403050417","DOIUrl":"https://doi.org/10.9790/1684-1403050417","url":null,"abstract":"This paper proposes an analytical scheme for stability analysis in turning process by considering the motion of tailstock-supported workpiece using a compliance model of tool and work. A dynamic cutting force model based on relative motion between the cutting tool and workpiece is developed to study the chatter stability. Linear stability analysis is carried out in the frequency domain and the stability charts are obtained with and without considering workpiece flexibility. Variations of stability limits with workpiece dimensions and cutter position as well as the effects of cutting tool dynamics are studied and wherever possible results are compared with existing models. Experimental analysis is conducted on tailstock-supported workpiece to examine the correctness of the proposed stability model.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"186 1","pages":"04-17"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75555248","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}
K. Begum, Ahammad Hossain, Farhana Mamtaz, N. Sharmin, A. Sarkar
{"title":"Naturally convective Casson fluid flow in presence of nano particle through porous plate with thermal radiation and MHD effects","authors":"K. Begum, Ahammad Hossain, Farhana Mamtaz, N. Sharmin, A. Sarkar","doi":"10.9790/1684-1403036370","DOIUrl":"https://doi.org/10.9790/1684-1403036370","url":null,"abstract":"","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"70 1","pages":"63-70"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81599043","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}
Low cost housing can be achieved by use of effective planning and project management, low cost materials, economical construction technologies and use of alternate construction methods available. . The selection of building materials should meet the needs of local circumstances to improve value of life for the most desired ones by building innovative structures or by refining existing structures. Various studies showed that a big variety of wall materials have been used in different building systems with traditional and modern construction methods, but only few of them (extruded clay bricks, hollow concrete blocks) have successfully been implemented in low-cost housing projects. The current era of real estate has ripened and the clay bricks and mortar are replaced with alternative construction materials like aerocon bricks. Innumerable properties in India are constructed with aerocon bricks and the method is rapidly flourishing. Some alternatives materials have already been used as a part of natural sand e.g. M-sand, fly-ash, slag limestone and siliceous stone powder are used in concrete mixtures as a partial replacement of natural sand. The main objective of this paper is to give detailed study on low cost building using aerocon block and M-sand.
{"title":"An Investigation of Using Aerocon Block and M-Sand in Constructing Low Cost Housing","authors":"K. Jaiganesh, S. Dinesh","doi":"10.9790/1684-1403017075","DOIUrl":"https://doi.org/10.9790/1684-1403017075","url":null,"abstract":"Low cost housing can be achieved by use of effective planning and project management, low cost materials, economical construction technologies and use of alternate construction methods available. . The selection of building materials should meet the needs of local circumstances to improve value of life for the most desired ones by building innovative structures or by refining existing structures. Various studies showed that a big variety of wall materials have been used in different building systems with traditional and modern construction methods, but only few of them (extruded clay bricks, hollow concrete blocks) have successfully been implemented in low-cost housing projects. The current era of real estate has ripened and the clay bricks and mortar are replaced with alternative construction materials like aerocon bricks. Innumerable properties in India are constructed with aerocon bricks and the method is rapidly flourishing. Some alternatives materials have already been used as a part of natural sand e.g. M-sand, fly-ash, slag limestone and siliceous stone powder are used in concrete mixtures as a partial replacement of natural sand. The main objective of this paper is to give detailed study on low cost building using aerocon block and M-sand.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"119 1","pages":"70-75"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76686451","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 mechanism of thermal autofrettage is described in relation to the more common mechanical autofrettage. This paper provides analytical and FE analysis of thermal autofrettage process has been conducted for spherical vessel considering von Mises yield criterion to predict behavior within the plastic zone. Elastic-plastic stress distribution subjected to thermal load are evaluated. This study include residual stress prediction on an uniaxial loading-unloading stresses of elastic perfectly plastic material model. Feasibility of Centrifugal and Centripetal autofrettage are discussed and compare.
{"title":"Analytical and Finite Element Analysis of Thermal Autofrettage process in Spherical vessel","authors":"R. Rupali, S. Mondal, S. Sarkar","doi":"10.9790/1684-1403021016","DOIUrl":"https://doi.org/10.9790/1684-1403021016","url":null,"abstract":"The mechanism of thermal autofrettage is described in relation to the more common mechanical autofrettage. This paper provides analytical and FE analysis of thermal autofrettage process has been conducted for spherical vessel considering von Mises yield criterion to predict behavior within the plastic zone. Elastic-plastic stress distribution subjected to thermal load are evaluated. This study include residual stress prediction on an uniaxial loading-unloading stresses of elastic perfectly plastic material model. Feasibility of Centrifugal and Centripetal autofrettage are discussed and compare.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"26 3 1","pages":"10-16"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87730151","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}
Concrete is a versatile used construction material and concrete has been accepted as a material for construction, researchers trying to improve its quality and enhance its performance. Recent changes in construction industry demand improved durability of structures. There is a methodological shift in the concrete design from a strength based concept to a performance based design. At present there is a large emphasis on performance aspect of concrete. One such thought has lead to the development of Self Compacting Concrete (SCC). SCC is a new kind of High Performance Concrete (HPC) with excellent deformability and segregation resistance. It can flow through self gravity and fill the gaps between reinforcement and corners of moulds without any need for vibration and compaction during the placing process. certain guidelines for fresh properties of SCC comes by The European Federation of Producers and Applicators of Specialist Products for Structures (EFNARC). The present investigation is aimed at developing high strength Self Compacting Concrete of M70 Grade. The parameters of study include grade of concrete and effect of size of aggregate.
{"title":"Effect of Size of Aggregate on Self Compacting Concrete of M70 Grade","authors":"M. Kasim, A. Amir, S. D. Bharti","doi":"10.9790/1684-1403018287","DOIUrl":"https://doi.org/10.9790/1684-1403018287","url":null,"abstract":"Concrete is a versatile used construction material and concrete has been accepted as a material for construction, researchers trying to improve its quality and enhance its performance. Recent changes in construction industry demand improved durability of structures. There is a methodological shift in the concrete design from a strength based concept to a performance based design. At present there is a large emphasis on performance aspect of concrete. One such thought has lead to the development of Self Compacting Concrete (SCC). SCC is a new kind of High Performance Concrete (HPC) with excellent deformability and segregation resistance. It can flow through self gravity and fill the gaps between reinforcement and corners of moulds without any need for vibration and compaction during the placing process. certain guidelines for fresh properties of SCC comes by The European Federation of Producers and Applicators of Specialist Products for Structures (EFNARC). The present investigation is aimed at developing high strength Self Compacting Concrete of M70 Grade. The parameters of study include grade of concrete and effect of size of aggregate.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"8 1","pages":"82-87"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83991454","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}
Earthquake is a major concerned natural disaster that causes great damage to the structure. Many multistoried commercial, factory and also residential building in Bangladesh are not designed properly considering seismic loads and also seismic zone effects, thereby large storey displacement and cracks have been observed in the structures. In the present study, a G+10 storied factory building is considered and finite element analysis software ETABS 2015 is used to determine the seismic demand and capacity of each structural element considering seismic zone 1 and zone 3. The building is preliminary designed and analyzed for zone 1 and found safe against seismic loads but vulnerable at zone 3. In the developing countries like Bangladesh, RC jacketing method is popular due to its cost effectiveness comparing with other strengthening methods. Therefore, in this study, a guideline for strengthening of columns only by RC jacketing method is discussed and analyzed. The columns having Demand Capacity Ratio (DCR) ratio more than 1.0 found from analysis are considered to strengthen. Pushover analysis is done to determine the performance of the structure before and after retrofitting and it is found that structure after retrofit have more base shear and displacement capacity, and less storey drift compared to unretrofitted structure.
{"title":"Seismic Performance Assessment of a Multistoried Building and Retrofitting of RC Columns","authors":"A. Hasan, M. G. Kibria, F. M. Hasan","doi":"10.9790/1684-1403027986","DOIUrl":"https://doi.org/10.9790/1684-1403027986","url":null,"abstract":"Earthquake is a major concerned natural disaster that causes great damage to the structure. Many multistoried commercial, factory and also residential building in Bangladesh are not designed properly considering seismic loads and also seismic zone effects, thereby large storey displacement and cracks have been observed in the structures. In the present study, a G+10 storied factory building is considered and finite element analysis software ETABS 2015 is used to determine the seismic demand and capacity of each structural element considering seismic zone 1 and zone 3. The building is preliminary designed and analyzed for zone 1 and found safe against seismic loads but vulnerable at zone 3. In the developing countries like Bangladesh, RC jacketing method is popular due to its cost effectiveness comparing with other strengthening methods. Therefore, in this study, a guideline for strengthening of columns only by RC jacketing method is discussed and analyzed. The columns having Demand Capacity Ratio (DCR) ratio more than 1.0 found from analysis are considered to strengthen. Pushover analysis is done to determine the performance of the structure before and after retrofitting and it is found that structure after retrofit have more base shear and displacement capacity, and less storey drift compared to unretrofitted structure.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"122 1","pages":"79-86"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89837052","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}
S. Rendevski, Mohammed Abdulrahman Almansoori, Abdullah Hamad Mohamed Ali Alsherwe
Low energy consumption for cooling houses/buildings is of great importance for countries in wide geographical and climate regions in the world (including UAE), when thinking on energy saving, supporting the economy growth and environmental protection. The main objective of the research is to show that this can be achieved by constructing the water pipes installation in houses/buildings to go through two walls in every room. In a lot of geographical/climate regions, incoming water is cold enough (bellow 22-24 0 C). A model house 1m x 1m has been constructed with similar materials to the real. Temperature-power-time dependence in the space has been monitored by thermocouples. Elements of Building Physics and Heat Transport Physics has been used to validate the efficiency of the model. The cost-benefit analysis (costs of pipes and fittings, additional equipment, labor hours) is in favor of the benefit of the proposed idea.
制冷房屋/建筑的低能耗对于世界上地理和气候区域广泛的国家(包括阿联酋)在考虑节能、支持经济增长和环境保护时具有重要意义。这项研究的主要目的是表明，这可以通过在房屋/建筑物中建造水管装置来实现，使其穿过每个房间的两堵墙。在许多地理/气候区域，来水足够冷(低于22- 240℃)。一个1m x 1m的模型房屋已经用与真实房屋相似的材料建造。热电偶监测了空间中的温度-功率-时间依赖关系。利用建筑物理学和热传输物理学的原理验证了模型的有效性。成本效益分析(管道和配件的成本、额外设备的成本、工时)支持所提出的想法的好处。
{"title":"Passive Cooling Of Houses by Placing the Municipality Running Water Installation inside the Walls","authors":"S. Rendevski, Mohammed Abdulrahman Almansoori, Abdullah Hamad Mohamed Ali Alsherwe","doi":"10.9790/1684-1403013343","DOIUrl":"https://doi.org/10.9790/1684-1403013343","url":null,"abstract":"Low energy consumption for cooling houses/buildings is of great importance for countries in wide geographical and climate regions in the world (including UAE), when thinking on energy saving, supporting the economy growth and environmental protection. The main objective of the research is to show that this can be achieved by constructing the water pipes installation in houses/buildings to go through two walls in every room. In a lot of geographical/climate regions, incoming water is cold enough (bellow 22-24 0 C). A model house 1m x 1m has been constructed with similar materials to the real. Temperature-power-time dependence in the space has been monitored by thermocouples. Elements of Building Physics and Heat Transport Physics has been used to validate the efficiency of the model. The cost-benefit analysis (costs of pipes and fittings, additional equipment, labor hours) is in favor of the benefit of the proposed idea.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"49 1","pages":"33-43"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75685184","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}
Arka Sen, M. Majumder, Sumit Mukhopadhyay, R. Biswas
This paper presents a detailed analysis of polar and orbit plots considering a non-faulty shaft and one with an unbalanced mass attached to it. Polar Plot analysis was done in order to determine the amplitude of vibration and the phase difference between faulty and non-faulty case. Also the orbit plot analysis provides a clear image of the two different cases, in which the area under the ellipse can be considered as the measure of the unbalance.
{"title":"Polar and Orbit Plot Analysis for Unbalance Identification in A Rotating System","authors":"Arka Sen, M. Majumder, Sumit Mukhopadhyay, R. Biswas","doi":"10.9790/1684-1403054956","DOIUrl":"https://doi.org/10.9790/1684-1403054956","url":null,"abstract":"This paper presents a detailed analysis of polar and orbit plots considering a non-faulty shaft and one with an unbalanced mass attached to it. Polar Plot analysis was done in order to determine the amplitude of vibration and the phase difference between faulty and non-faulty case. Also the orbit plot analysis provides a clear image of the two different cases, in which the area under the ellipse can be considered as the measure of the unbalance.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"43 1","pages":"49-56"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87869059","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}
Detrimental variations worldwide have led to deleterious effects such as cost overruns, time overruns, compromised quality and abandonment of building projects. The study was about to identify and evaluate potential mitigation measures of detrimental variations in public building projects in Tanzania. This could help in minimizing detrimental variations and consequently safeguarding the anticipated value for money in such projects. Reviewed relevant literature resulted into identification of 17 potential mitigation measures of detrimental variations in public building projects. In total, 183 questionnaire forms were administered to architects, engineers, quantity surveyors and procurement officers for rating. Nevertheless, 143 responses were received constituting 78% response rate. Moreover, semi-structured interviews were made with 24 selected experienced professionals in public building projects to elicit individual’s expert opinion regarding mitigation measures of detrimental variations. Descriptive and inferential statistics such as frequencies, Cronbach’s alpha coefficient, coefficient of variations, Principal Component Analysis (PCA) and t-test were used to analyse and syntheses data. Study finding indicates the top five highly ranked potential mitigation measures of detrimental variations as joint efforts by project parties to control variation orders, clear project specifications, comprehensive site investigations, use of project scheduling techniques and use of knowledge base of previous similar projects. The agreement among respondents in rating and ranking mitigation factors was found to be significant. Overall, respondents tended to agree that all rated and ranked 17 mitigation measures could be practical to minimise detrimental variations in construction projects since their expected values of discrete random variables were greater than 3. Results from this study should help professionals, academicians, researchers and policy makers to reduce detrimental variations and subsequently improve performance of construction projects.
{"title":"Determining Significant Mitigation Measures of Detrimental Variations in Public Building Projects in Tanzania","authors":"Y. Mhando, R. Mlinga, H. Alinaitwe","doi":"10.9790/1684-1403011525","DOIUrl":"https://doi.org/10.9790/1684-1403011525","url":null,"abstract":"Detrimental variations worldwide have led to deleterious effects such as cost overruns, time overruns, compromised quality and abandonment of building projects. The study was about to identify and evaluate potential mitigation measures of detrimental variations in public building projects in Tanzania. This could help in minimizing detrimental variations and consequently safeguarding the anticipated value for money in such projects. Reviewed relevant literature resulted into identification of 17 potential mitigation measures of detrimental variations in public building projects. In total, 183 questionnaire forms were administered to architects, engineers, quantity surveyors and procurement officers for rating. Nevertheless, 143 responses were received constituting 78% response rate. Moreover, semi-structured interviews were made with 24 selected experienced professionals in public building projects to elicit individual’s expert opinion regarding mitigation measures of detrimental variations. Descriptive and inferential statistics such as frequencies, Cronbach’s alpha coefficient, coefficient of variations, Principal Component Analysis (PCA) and t-test were used to analyse and syntheses data. Study finding indicates the top five highly ranked potential mitigation measures of detrimental variations as joint efforts by project parties to control variation orders, clear project specifications, comprehensive site investigations, use of project scheduling techniques and use of knowledge base of previous similar projects. The agreement among respondents in rating and ranking mitigation factors was found to be significant. Overall, respondents tended to agree that all rated and ranked 17 mitigation measures could be practical to minimise detrimental variations in construction projects since their expected values of discrete random variables were greater than 3. Results from this study should help professionals, academicians, researchers and policy makers to reduce detrimental variations and subsequently improve performance of construction projects.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"40 1","pages":"15-25"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78680060","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}
Pub Date : 2017-05-01DOI: 10.9790/1684-14030297101
L. Barbosa
The duplex steels are widely used in the area of oil exploration, both in structure and equipment. These steels provide excellent mechanical properties combined with excellent corrosion resistance. The welding of this material takes into account the loss of alloying elements, which are directly linked to the excellent properties of this material, this loss being compensated by the addition of metal during welding. In an autogenous weld, this addition of material to balance the loss is eliminated, and under these conditions, a study subjecting the duplex UNS S31803 steel to this process, a relationship between the microstructure of the weld region and an electrochemical characterization, will be shown that this loss does not interfere with the quality of the weld and the resistance of the material to corrosion.
{"title":"Characterization Electrochemical Duplex Steel UNS S31803 Welded By TIG Autogenous","authors":"L. Barbosa","doi":"10.9790/1684-14030297101","DOIUrl":"https://doi.org/10.9790/1684-14030297101","url":null,"abstract":"The duplex steels are widely used in the area of oil exploration, both in structure and equipment. These steels provide excellent mechanical properties combined with excellent corrosion resistance. The welding of this material takes into account the loss of alloying elements, which are directly linked to the excellent properties of this material, this loss being compensated by the addition of metal during welding. In an autogenous weld, this addition of material to balance the loss is eliminated, and under these conditions, a study subjecting the duplex UNS S31803 steel to this process, a relationship between the microstructure of the weld region and an electrochemical characterization, will be shown that this loss does not interfere with the quality of the weld and the resistance of the material to corrosion.","PeriodicalId":14565,"journal":{"name":"IOSR Journal of Mechanical and Civil Engineering","volume":"33 8","pages":"97-101"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91404182","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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