This study investigated the influence of iron concentration on the thermodynamic properties of syndiotactic polypropylene (sPP)/iron composites in the melt phase in a series of samples with varying iron content, ranging from 0 to 10% with a step of 2%. The HYSYS software was used to estimate molecular weight, critical temperature (Tc), critical volume (Vc), and eccentricity (Ec). The results showed that all these properties changed as the iron content varied. The findings of this study confirmed that iron concentration has an impact on the mechanical and chain dynamic (microscopic) properties of polymer composites.
{"title":"The Effect of Iron Content on the Thermodynamic Properties of Syndiotactic Polypropylene/Iron Composites","authors":"Naveed Ahmad, Farooq Ahmad","doi":"10.48084/etasr.6241","DOIUrl":"https://doi.org/10.48084/etasr.6241","url":null,"abstract":"This study investigated the influence of iron concentration on the thermodynamic properties of syndiotactic polypropylene (sPP)/iron composites in the melt phase in a series of samples with varying iron content, ranging from 0 to 10% with a step of 2%. The HYSYS software was used to estimate molecular weight, critical temperature (Tc), critical volume (Vc), and eccentricity (Ec). The results showed that all these properties changed as the iron content varied. The findings of this study confirmed that iron concentration has an impact on the mechanical and chain dynamic (microscopic) properties of polymer composites.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135917879","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}
This study collected data on road accidents for the years 2016-2020 for the NH-48 highway in Maharashtra, India to model their conditions. Road crash data models were developed using 70% of actual data for training and 30% for testing purposes. Negative binomial regression modeling was used to predict crash fatalities. The results showed that the factors that affected the fatality of road crashes were head-on-collision, friction, time zone, and weather conditions of the crash. The developed models were validated and tested using log-likelihood, AIC, BIC, MAD, MSE, RMSE, and MAPE values. Head-on-collision, AM, PM, light rain, mist/fog, heavy rain, fine, and cloudy were positively associated with the fatality of road crashes, while friction was negatively associated. The developed models can be used to predict the fatality/non-fatality of road crashes and implement road safety strategies on highways to reduce them.
{"title":"Count Data Modeling for Predicting Crash Severity on Indian Highways","authors":"Krantikumar V. Mhetre, Aruna D. Thube","doi":"10.48084/etasr.6172","DOIUrl":"https://doi.org/10.48084/etasr.6172","url":null,"abstract":"This study collected data on road accidents for the years 2016-2020 for the NH-48 highway in Maharashtra, India to model their conditions. Road crash data models were developed using 70% of actual data for training and 30% for testing purposes. Negative binomial regression modeling was used to predict crash fatalities. The results showed that the factors that affected the fatality of road crashes were head-on-collision, friction, time zone, and weather conditions of the crash. The developed models were validated and tested using log-likelihood, AIC, BIC, MAD, MSE, RMSE, and MAPE values. Head-on-collision, AM, PM, light rain, mist/fog, heavy rain, fine, and cloudy were positively associated with the fatality of road crashes, while friction was negatively associated. The developed models can be used to predict the fatality/non-fatality of road crashes and implement road safety strategies on highways to reduce them.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135917992","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}
Document Co-citation Analysis (DCA) is a method to identify and analyze the relationships between co-cited documents. In this paper, we attempt to use concept lattice for DCA. Concept lattice is a graph structure given in Formal Concept Analysis (FCA), a branch of mathematics based on the concept and its hierarchy. The experiments are conducted on an extensive repository of citations extracted from DBLP, ACM, MAG (Microsoft Academic Graph), and other sources, having a total of 5,354,309 papers and 48,227,950 citation relationships. In this paper, it is established that the concept lattice supports DCA and helps to identify a set of co-cited documents and their co-citation strength. It also provides navigation to reflect the subset-superset relationship of the co-citations. Further, the concept lattice helps identify the hierarchy among the documents and answers the most relevant queries related to DCA.
{"title":"Document Co-citation Analysis using Concept Lattice","authors":"Anamika Gupta, Shikha Gupta, Mukul Bisht, Prestha Hooda, Md Salik","doi":"10.48084/etasr.6201","DOIUrl":"https://doi.org/10.48084/etasr.6201","url":null,"abstract":"Document Co-citation Analysis (DCA) is a method to identify and analyze the relationships between co-cited documents. In this paper, we attempt to use concept lattice for DCA. Concept lattice is a graph structure given in Formal Concept Analysis (FCA), a branch of mathematics based on the concept and its hierarchy. The experiments are conducted on an extensive repository of citations extracted from DBLP, ACM, MAG (Microsoft Academic Graph), and other sources, having a total of 5,354,309 papers and 48,227,950 citation relationships. In this paper, it is established that the concept lattice supports DCA and helps to identify a set of co-cited documents and their co-citation strength. It also provides navigation to reflect the subset-superset relationship of the co-citations. Further, the concept lattice helps identify the hierarchy among the documents and answers the most relevant queries related to DCA.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918045","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 cost of energy is directly influenced by geopolitical, economic, and environmental factors. There is an international trend towards renewable resources, although the implementation pace and legislation in force have issues. Complete abolishment of fossil fuels is practically impossible. Evolution is only possible with the use of these fuels but with modern, efficient equipment to reduce the pollution resulting from the process of extracting, processing, and using fossil fuels. In this paper, a screw compressor with oil injection, used in oil extraction stations, is analyzed numerically. This analysis is useful in the process of modernizing and improving the efficiency of this type of compressor, which is capable of operating in extreme working regimes, highly contaminated with impurities. The numerical analysis presented certain challenges related to biphasic flow in extremely small spaces at high compression ratios. The results include the absolute pressure variation and the flow rate variation. Regarding future research, test series will be carried out to validate the numerical results on the test bench with a 1:1 scale prototype.
{"title":"Computational Fluid Dynamics Evaluation of an Oil-flooded Screw Compressor","authors":"Ion Malael, Valentin Petrescu","doi":"10.48084/etasr.6122","DOIUrl":"https://doi.org/10.48084/etasr.6122","url":null,"abstract":"The cost of energy is directly influenced by geopolitical, economic, and environmental factors. There is an international trend towards renewable resources, although the implementation pace and legislation in force have issues. Complete abolishment of fossil fuels is practically impossible. Evolution is only possible with the use of these fuels but with modern, efficient equipment to reduce the pollution resulting from the process of extracting, processing, and using fossil fuels. In this paper, a screw compressor with oil injection, used in oil extraction stations, is analyzed numerically. This analysis is useful in the process of modernizing and improving the efficiency of this type of compressor, which is capable of operating in extreme working regimes, highly contaminated with impurities. The numerical analysis presented certain challenges related to biphasic flow in extremely small spaces at high compression ratios. The results include the absolute pressure variation and the flow rate variation. Regarding future research, test series will be carried out to validate the numerical results on the test bench with a 1:1 scale prototype.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"260 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918171","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}
This study presents a combination of Type-2 fuzzy logic and nonsingular fast sliding mode technique to design a robust controller for a robotic system. The control law is composed of two signals. The first one called equivalent control law is dedicated to maintaining the system on the sliding surface and then converges to zero. Since the system is uncertain, a Type-2 fuzzy nominal model was constructed, deduced from linear local models, which allows a good approximation of the real robotic system. The second signal, whose objective is to force the system to attain the sliding surface, is deduced from stability analysis using Lyapunov theory. Several simulations were conducted to evaluate the efficiency of the proposed approach, showing good tracking performance for different reference signals despite the presence of uncertainties and external disturbances.
{"title":"Nonsingular Fast Terminal Sliding Mode Controller for a Robotic System: A Fuzzy Approach","authors":"Lafi Alnufaie","doi":"10.48084/etasr.6151","DOIUrl":"https://doi.org/10.48084/etasr.6151","url":null,"abstract":"This study presents a combination of Type-2 fuzzy logic and nonsingular fast sliding mode technique to design a robust controller for a robotic system. The control law is composed of two signals. The first one called equivalent control law is dedicated to maintaining the system on the sliding surface and then converges to zero. Since the system is uncertain, a Type-2 fuzzy nominal model was constructed, deduced from linear local models, which allows a good approximation of the real robotic system. The second signal, whose objective is to force the system to attain the sliding surface, is deduced from stability analysis using Lyapunov theory. Several simulations were conducted to evaluate the efficiency of the proposed approach, showing good tracking performance for different reference signals despite the presence of uncertainties and external disturbances.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918307","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}
Cuong Nguyen Van, Anh Le Hoang, Cao Dang Long, Duy Nguyen Hoang
This study investigates the influence of printing orientation on the surface roughness in metal material extrusion 3D printing of 17-4 PH stainless steel. Experimental tests were conducted on the Markforged Metal X commercial 3D printer at Vinh Long University of Technology Education, Vietnam. The samples were printed in three different orientations: flat, on-edge, and upright. Surface roughness measurements were performed using a handheld Mitutoyo SJ-210 roughness tester. Quantitative analysis of the surface roughness measurements revealed significant variations among the different printing orientations. The upright orientation exhibited the smoothest surface, with an average Ra value of 7.42 μm and Rz value of 40.49 μm. In contrast, the flat orientation showed the highest roughness, with an average Ra value of 82.83 μm and Rz value of 109.32 μm. The on-edge orientation had intermediate roughness values, with an average Ra value of 69.42 μm and Rz value of 92.17 μm. The study also introduces a novel predictive model for surface roughness based on the printing parameters. The model demonstrated accurate estimations for surface roughness values in specific cases, enabling optimization of the printing process for desired surface quality.
{"title":"Surface Roughness in Metal Material Extrusion 3D Printing: The Influence of Printing Orientation and the Development of a Predictive Model","authors":"Cuong Nguyen Van, Anh Le Hoang, Cao Dang Long, Duy Nguyen Hoang","doi":"10.48084/etasr.6162","DOIUrl":"https://doi.org/10.48084/etasr.6162","url":null,"abstract":"This study investigates the influence of printing orientation on the surface roughness in metal material extrusion 3D printing of 17-4 PH stainless steel. Experimental tests were conducted on the Markforged Metal X commercial 3D printer at Vinh Long University of Technology Education, Vietnam. The samples were printed in three different orientations: flat, on-edge, and upright. Surface roughness measurements were performed using a handheld Mitutoyo SJ-210 roughness tester. Quantitative analysis of the surface roughness measurements revealed significant variations among the different printing orientations. The upright orientation exhibited the smoothest surface, with an average Ra value of 7.42 μm and Rz value of 40.49 μm. In contrast, the flat orientation showed the highest roughness, with an average Ra value of 82.83 μm and Rz value of 109.32 μm. The on-edge orientation had intermediate roughness values, with an average Ra value of 69.42 μm and Rz value of 92.17 μm. The study also introduces a novel predictive model for surface roughness based on the printing parameters. The model demonstrated accurate estimations for surface roughness values in specific cases, enabling optimization of the printing process for desired surface quality.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"139 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918473","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}
This paper proposes a design of a 38 GHz Low Noise Amplifier (LNA) that uses a three-stage common source inductive degeneration topology with a gain of 27 dB and noise figure of 1.78 dB using 0.1 µm GaAs pHEMT as an active device. The novelty of the design is the usage of inductive load in series with the resistor instead of resistive load, resulting in higher gain performance. A recent pp1010 active device of WIN foundry was explored for this LNA design at the Q band. The high transition frequency offered by this technology succeeded in obtaining competitive results with a minimum number of cells. The designed LNA obtained the lowest noise compared to other recently published LNA designs at the Q band. The total power consumption of this design is 57 mW.
{"title":"A Low Noise Amplifier with 27 dB Gain and 1.78 dB Noise for Satellite Communications with 0.1 µm GaAs pHEMT Technology","authors":"Lakshmi Balla, Venkata Krishna Sharma Gollakota","doi":"10.48084/etasr.6264","DOIUrl":"https://doi.org/10.48084/etasr.6264","url":null,"abstract":"This paper proposes a design of a 38 GHz Low Noise Amplifier (LNA) that uses a three-stage common source inductive degeneration topology with a gain of 27 dB and noise figure of 1.78 dB using 0.1 µm GaAs pHEMT as an active device. The novelty of the design is the usage of inductive load in series with the resistor instead of resistive load, resulting in higher gain performance. A recent pp1010 active device of WIN foundry was explored for this LNA design at the Q band. The high transition frequency offered by this technology succeeded in obtaining competitive results with a minimum number of cells. The designed LNA obtained the lowest noise compared to other recently published LNA designs at the Q band. The total power consumption of this design is 57 mW.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918754","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}
Shiva Kumar Nimmakayala, Bala Sai Srilatha Indira Dutt Vemuri
The disturbances and irregularities in the ionosphere are the primarily recognized ramifications of space weather called scintillations. Irregularities in the electron densities are the source of the ionospheric scintillations. This article investigates the ionospheric scintillations, which are predominant in the trans-equatorial and equatorial regions. Based on the data from a multi-constellation Global Navigation Satellite Systems (GNSS) receiver at the Chaitanya Bharathi Institute of Technology Hyderabad, the relationship between the amplitude scintillation index S4 and the rate of change of total electron content (ROTI) is examined. The correlation coefficient between S4 and ROTI is demonstrated in this article. The outcome validates the usefulness of the ROTI in identifying the scintillations.
{"title":"Analysis of Ionospheric Scintillations using GPS and NavIC Combined Constellation","authors":"Shiva Kumar Nimmakayala, Bala Sai Srilatha Indira Dutt Vemuri","doi":"10.48084/etasr.5863","DOIUrl":"https://doi.org/10.48084/etasr.5863","url":null,"abstract":"The disturbances and irregularities in the ionosphere are the primarily recognized ramifications of space weather called scintillations. Irregularities in the electron densities are the source of the ionospheric scintillations. This article investigates the ionospheric scintillations, which are predominant in the trans-equatorial and equatorial regions. Based on the data from a multi-constellation Global Navigation Satellite Systems (GNSS) receiver at the Chaitanya Bharathi Institute of Technology Hyderabad, the relationship between the amplitude scintillation index S4 and the rate of change of total electron content (ROTI) is examined. The correlation coefficient between S4 and ROTI is demonstrated in this article. The outcome validates the usefulness of the ROTI in identifying the scintillations.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135911756","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 purpose of this study is to identify and rank the factors influencing the bid/no-bid decision according to their relative importance from the perspective of the contractors in the West Bank in Palestine. To achieve the study objectives, a questionnaire survey was conducted. The survey covered a randomly selected sample of 64 contractors involved in the construction industry in the West Bank. The questionnaire’s structure is based on the related literature, the pilot study, and the feedback from local experts in the construction industry. A total of 32 factors that might influence the bid/no-bid decision were identified and considered. Then, the targeted population was asked to rank these factors according to their relative importance. The results indicate that the top five factors affecting a contractor’s decision to bid or not include the financial stability of the client, the identity and reputation of the client in the industry, the promptness of the client in the payment process, the expected profitability, and the project’s source of funding. On the other hand, the least affecting factors are the type of the project, client’s requirements, taxes, laws and government regulations, and weather conditions. The paper provides a comprehensive understanding of the factors affecting the bidding decision. Construction parties and researchers could benefit from the results of this study.
{"title":"Critical Factors Influencing the Bid / No-Bid Decision in the Palestinian Construction Industry","authors":"I. Mahamid","doi":"10.48084/etasr.4538","DOIUrl":"https://doi.org/10.48084/etasr.4538","url":null,"abstract":"The purpose of this study is to identify and rank the factors influencing the bid/no-bid decision according to their relative importance from the perspective of the contractors in the West Bank in Palestine. To achieve the study objectives, a questionnaire survey was conducted. The survey covered a randomly selected sample of 64 contractors involved in the construction industry in the West Bank. The questionnaire’s structure is based on the related literature, the pilot study, and the feedback from local experts in the construction industry. A total of 32 factors that might influence the bid/no-bid decision were identified and considered. Then, the targeted population was asked to rank these factors according to their relative importance. The results indicate that the top five factors affecting a contractor’s decision to bid or not include the financial stability of the client, the identity and reputation of the client in the industry, the promptness of the client in the payment process, the expected profitability, and the project’s source of funding. On the other hand, the least affecting factors are the type of the project, client’s requirements, taxes, laws and government regulations, and weather conditions. The paper provides a comprehensive understanding of the factors affecting the bidding decision. Construction parties and researchers could benefit from the results of this study.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"8 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85181794","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}
Pumps are energetic devices that are present in a wide range of industries. Their installed power varies from a few tens of watts up to hundreds of megawatts. As the energy consumption is connected with global warming and climate change, the development of pumps that have good characteristics is very important. Theoretical and experimental methods have long been utilized in the development of pumps, but recently much research has been carried out with the help of Computational Fluid Dynamics (CFD) analysis. Certain numerical analyses can be of high quality and accurate, but special operational phenomena still occur, where special attention is required when performing analysis. This category includes operating regimes outside the Best Efficiency Point (BEP), the formation of inlet recirculation, cavitation, and the influence of wall roughness on all the above characteristics. The current paper presents the main problems that developers face when numerically analyzing the above-mentioned special operating regimes. Both numerical and experimental results are considered.
{"title":"Challenges in the Numerical Analysis of Centrifugal Pumps¨: Energetic, Cavitation and Dynamic Characteristics","authors":"A. Lipej","doi":"10.48084/etasr.4647","DOIUrl":"https://doi.org/10.48084/etasr.4647","url":null,"abstract":"Pumps are energetic devices that are present in a wide range of industries. Their installed power varies from a few tens of watts up to hundreds of megawatts. As the energy consumption is connected with global warming and climate change, the development of pumps that have good characteristics is very important. Theoretical and experimental methods have long been utilized in the development of pumps, but recently much research has been carried out with the help of Computational Fluid Dynamics (CFD) analysis. Certain numerical analyses can be of high quality and accurate, but special operational phenomena still occur, where special attention is required when performing analysis. This category includes operating regimes outside the Best Efficiency Point (BEP), the formation of inlet recirculation, cavitation, and the influence of wall roughness on all the above characteristics. The current paper presents the main problems that developers face when numerically analyzing the above-mentioned special operating regimes. Both numerical and experimental results are considered.","PeriodicalId":11826,"journal":{"name":"Engineering, Technology & Applied Science Research","volume":"PP 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84170694","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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