Pub Date : 2023-07-27DOI: 10.1177/03064190231188866
Carlos Alberto de Freitas, Rubens Alves Dias
The present article discusses whether higher engineering and technology courses in Brazil prepare students for professional practice in the maintenance segment, froman educational theoretical framework point of view. To achieve this, the theme significance was researched in Scopus and ScienceDirect bases. The work proposal is based on the concepts of teaching and learning by Vygotsky, confronting the methods used by professors’ engineers, which multiply what they learned in higher education courses. In the planned research, we intend to understand the paradigms and skills of the maintainer considering the action research methods, through the ILS tool—Index of Learning Styles by Felder and Solomon. To analyze the students’ learning profile regarding their preferences for receiving information, we discuss the scenarios generated, expecting to design a teaching and learning process centered on students, an assumption based on Vygotsky's cognitive theory, in which an individual's learning process is related to their interaction in the social environment that they are. As a result, the proposed teaching practices made it possible to increase personal interest in learning, and we observed that there was less difference between the students’ learning styles and also noticed the same profile in the four dimensions, both morning and evening scenarios. Students consider themselves active, sensory, visual, and global.
{"title":"Professional training in industrial maintenance: A social interactionist approach","authors":"Carlos Alberto de Freitas, Rubens Alves Dias","doi":"10.1177/03064190231188866","DOIUrl":"https://doi.org/10.1177/03064190231188866","url":null,"abstract":"The present article discusses whether higher engineering and technology courses in Brazil prepare students for professional practice in the maintenance segment, froman educational theoretical framework point of view. To achieve this, the theme significance was researched in Scopus and ScienceDirect bases. The work proposal is based on the concepts of teaching and learning by Vygotsky, confronting the methods used by professors’ engineers, which multiply what they learned in higher education courses. In the planned research, we intend to understand the paradigms and skills of the maintainer considering the action research methods, through the ILS tool—Index of Learning Styles by Felder and Solomon. To analyze the students’ learning profile regarding their preferences for receiving information, we discuss the scenarios generated, expecting to design a teaching and learning process centered on students, an assumption based on Vygotsky's cognitive theory, in which an individual's learning process is related to their interaction in the social environment that they are. As a result, the proposed teaching practices made it possible to increase personal interest in learning, and we observed that there was less difference between the students’ learning styles and also noticed the same profile in the four dimensions, both morning and evening scenarios. Students consider themselves active, sensory, visual, and global.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45069980","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 : 2023-07-24DOI: 10.1177/03064190231175231
Lisa Wang Jianwu, Lim See Yew, Lin Kok On, Tan Chee Keong, Ricky Tan Yuan Sheng, Sairin Bin Sani, Tan Hwee Juan Agnes
AMCAD ( www.amcad.ai ) is a web-enabled artificial intelligence (AI) system created to auto-evaluate students’ computer-aided drawing (CAD) work assignments and help students in self-directed learning. It compares two engineering drawings and highlights the differences (errors) between the two. The errors are classified into two categories: “Missing Line” errors shown in red and “Erroneous Line” errors in blue. AMCAD works in tandem with all CAD software. It uses computer vision technology to convert PDF drawings to raster subimages, and XOR to evaluate quantitatively the best-matched with best-aligned views. AMCAD, whose AI algorithms and web application were developed in Python, shows the comparison results in two display modes: superimpose and side-by-side. To encourage students in self-directed leaning, instructional videos can be included in each CAD work assignment.
{"title":"Artificial intelligence-enabled evaluating for computer-aided drawings (AMCAD)","authors":"Lisa Wang Jianwu, Lim See Yew, Lin Kok On, Tan Chee Keong, Ricky Tan Yuan Sheng, Sairin Bin Sani, Tan Hwee Juan Agnes","doi":"10.1177/03064190231175231","DOIUrl":"https://doi.org/10.1177/03064190231175231","url":null,"abstract":"AMCAD ( www.amcad.ai ) is a web-enabled artificial intelligence (AI) system created to auto-evaluate students’ computer-aided drawing (CAD) work assignments and help students in self-directed learning. It compares two engineering drawings and highlights the differences (errors) between the two. The errors are classified into two categories: “Missing Line” errors shown in red and “Erroneous Line” errors in blue. AMCAD works in tandem with all CAD software. It uses computer vision technology to convert PDF drawings to raster subimages, and XOR to evaluate quantitatively the best-matched with best-aligned views. AMCAD, whose AI algorithms and web application were developed in Python, shows the comparison results in two display modes: superimpose and side-by-side. To encourage students in self-directed leaning, instructional videos can be included in each CAD work assignment.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41541357","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 : 2023-07-13DOI: 10.1177/03064190231185329
Dominga Sanchez, Amy L. Brooks, H. Nembhard, Shane A. Brown
Involvement in professional disciplinary engineering student organizations (PDESOs) positively influences engineering students’ college experience. While extensive research about engineering student societies and organizations has demonstrated various benefits for students, few studies explore professional disciplinary engineering student societies and organizations that provide unique opportunities tailored around specific engineering disciplines. To better understand how participation in PDESOs influences engineering undergraduates, we conducted an exploratory study, interviewing thirteen mechanical engineering undergraduates with six months to three years of experience with PDESOs. The overarching conceptual framework is derived from a combination of motivated identity construction theory and engineering identity, allowing us to see how participation in these organizations contributes to students’ engineering identity and professional development. Participants indicated that involvement in PDESOs provided unique professional development opportunities that enhanced their self-esteem and efficacy and provided a welcoming environment where they experienced a sense of belonging. These results demonstrate that participation in PDESOs contributes to professional development, interpersonal skills, and community engagement, preparing them for the engineering workforce, which contributes to a strengthened engineering identity.
{"title":"An exploratory study on how mechanical engineering undergraduates perceive participation in professional disciplinary engineering student organizations that influence their engineering identity","authors":"Dominga Sanchez, Amy L. Brooks, H. Nembhard, Shane A. Brown","doi":"10.1177/03064190231185329","DOIUrl":"https://doi.org/10.1177/03064190231185329","url":null,"abstract":"Involvement in professional disciplinary engineering student organizations (PDESOs) positively influences engineering students’ college experience. While extensive research about engineering student societies and organizations has demonstrated various benefits for students, few studies explore professional disciplinary engineering student societies and organizations that provide unique opportunities tailored around specific engineering disciplines. To better understand how participation in PDESOs influences engineering undergraduates, we conducted an exploratory study, interviewing thirteen mechanical engineering undergraduates with six months to three years of experience with PDESOs. The overarching conceptual framework is derived from a combination of motivated identity construction theory and engineering identity, allowing us to see how participation in these organizations contributes to students’ engineering identity and professional development. Participants indicated that involvement in PDESOs provided unique professional development opportunities that enhanced their self-esteem and efficacy and provided a welcoming environment where they experienced a sense of belonging. These results demonstrate that participation in PDESOs contributes to professional development, interpersonal skills, and community engagement, preparing them for the engineering workforce, which contributes to a strengthened engineering identity.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48959137","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 : 2023-07-12DOI: 10.1177/03064190231186699
S. Kontomaris, A. Malamou
Determining the period of a nonlinear oscillation is a challenging task that requires a strong mathematical background in solving nonlinear differential equations. However, the procedure can be significantly simplified using the area under the 1/|υ|= f(x) graph, where υ is the velocity of the oscillating object and x is its displacement from its equilibrium position. The proposed method requires elementary computational tools and is appropriate for determining the period of any nonlinear undamped oscillation. Characteristic examples are presented, such as the simple pendulum, the oscillation with a power-law restoring force, and the cubic-quintic Duffing oscillator. The proposed approach provides accurate results and is appropriate for introductory physics and mechanics courses.
{"title":"Nonlinear oscillations for beginners. Calculating period using an elementary computational approach","authors":"S. Kontomaris, A. Malamou","doi":"10.1177/03064190231186699","DOIUrl":"https://doi.org/10.1177/03064190231186699","url":null,"abstract":"Determining the period of a nonlinear oscillation is a challenging task that requires a strong mathematical background in solving nonlinear differential equations. However, the procedure can be significantly simplified using the area under the 1/|υ|= f(x) graph, where υ is the velocity of the oscillating object and x is its displacement from its equilibrium position. The proposed method requires elementary computational tools and is appropriate for determining the period of any nonlinear undamped oscillation. Characteristic examples are presented, such as the simple pendulum, the oscillation with a power-law restoring force, and the cubic-quintic Duffing oscillator. The proposed approach provides accurate results and is appropriate for introductory physics and mechanics courses.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43812789","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 : 2023-07-05DOI: 10.1177/03064190231185326
Son Hoang, C. Tran, Van Tinh Pham, Van Tuu Nguyen, Van Tung Tran, V. Tran, Thi Tham Nguyen
This study evaluates the performance of learning CNC machining in mechanical engineering degree programs by assessing students’ mental workload (MWL). Both subjective (NASA-Task Load Index) and objective (increasing ratio of heart rate, IRH) evaluation methods were employed to assess the MWL of 46 students randomly assigned to two groups: a traditional training group and a combined simulation training group. The results demonstrate the significant impact of the training method on students’ MWL. Specifically, the MWL and IHR values of the combined simulation training group were 54.3 and 9.2, respectively, while those of the traditional training group were 58.3 and 13.2. Additionally, the correlation analysis showed a significant correlation between the IHR value and the MWL score of NASA-TLX. These findings suggest that implementing simulated software and the combined simulation training method effectively reduces students’ MWL, thereby promoting active knowledge acquisition. Consequently, students’ MWL can be utilized to evaluate the effectiveness of technical education with the aim of enhancing training efficiency and quality.
{"title":"Evaluating the learning performances for CNC machine practice in mechanical engineering degree courses based on students’ mental workload","authors":"Son Hoang, C. Tran, Van Tinh Pham, Van Tuu Nguyen, Van Tung Tran, V. Tran, Thi Tham Nguyen","doi":"10.1177/03064190231185326","DOIUrl":"https://doi.org/10.1177/03064190231185326","url":null,"abstract":"This study evaluates the performance of learning CNC machining in mechanical engineering degree programs by assessing students’ mental workload (MWL). Both subjective (NASA-Task Load Index) and objective (increasing ratio of heart rate, IRH) evaluation methods were employed to assess the MWL of 46 students randomly assigned to two groups: a traditional training group and a combined simulation training group. The results demonstrate the significant impact of the training method on students’ MWL. Specifically, the MWL and IHR values of the combined simulation training group were 54.3 and 9.2, respectively, while those of the traditional training group were 58.3 and 13.2. Additionally, the correlation analysis showed a significant correlation between the IHR value and the MWL score of NASA-TLX. These findings suggest that implementing simulated software and the combined simulation training method effectively reduces students’ MWL, thereby promoting active knowledge acquisition. Consequently, students’ MWL can be utilized to evaluate the effectiveness of technical education with the aim of enhancing training efficiency and quality.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43159455","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 : 2023-06-30DOI: 10.14445/23488360/ijme-v10i6p105
Ganga S, Deepthy S Nair, Rojan Mathew
- Liquid propellant rocket utilizes an engine that uses liquid as a propellant. In liquid propellant rockets, fuel and oxidizer are pumped into the combustion chamber, where they get mixed and burned. Liquid hydrogen is mainly used as fuel, and liquid oxygen is used as an oxidizer. Slosh can occur with liquid propellants. Slosh acts as a tuned damper and helps in reducing the dynamic response of the vehicle. Slosh baffles in the tanks and intelligent control rules in the guidance system can be used to control this. A potential source of disturbance that is vital to the stability of spacecraft is the propellant slosh. A mechanical model of a spring-mass-damper system is commonly used to represent the sloshing dynamics. Modelling of a typical liquid propellant rocket propellant is done in MSC NASTRAN / PATRAN software. Dynamic characterization of liquid propellant rockets with and without propellant is carried out. Transient analysis on launch vehicles with propellant is carried out, and responses at critical locations are estimated. In this project, the structural dynamic characterization and response at critical locations of a liquid propellant rocket are conducted. The main objective of the project is to study the effect of coupling between the propellant sloshing and the vehicle modes.
{"title":"Effect of Dynamic Coupling of Liquid Propellant Sloshing on the Response at Critical Locations of a Typical Liquid Propellant Rocket","authors":"Ganga S, Deepthy S Nair, Rojan Mathew","doi":"10.14445/23488360/ijme-v10i6p105","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i6p105","url":null,"abstract":"- Liquid propellant rocket utilizes an engine that uses liquid as a propellant. In liquid propellant rockets, fuel and oxidizer are pumped into the combustion chamber, where they get mixed and burned. Liquid hydrogen is mainly used as fuel, and liquid oxygen is used as an oxidizer. Slosh can occur with liquid propellants. Slosh acts as a tuned damper and helps in reducing the dynamic response of the vehicle. Slosh baffles in the tanks and intelligent control rules in the guidance system can be used to control this. A potential source of disturbance that is vital to the stability of spacecraft is the propellant slosh. A mechanical model of a spring-mass-damper system is commonly used to represent the sloshing dynamics. Modelling of a typical liquid propellant rocket propellant is done in MSC NASTRAN / PATRAN software. Dynamic characterization of liquid propellant rockets with and without propellant is carried out. Transient analysis on launch vehicles with propellant is carried out, and responses at critical locations are estimated. In this project, the structural dynamic characterization and response at critical locations of a liquid propellant rocket are conducted. The main objective of the project is to study the effect of coupling between the propellant sloshing and the vehicle modes.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":"1 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84774349","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 : 2023-06-30DOI: 10.14445/23488360/ijme-v10i6p101
Nguyen Van Thuyen
{"title":"Calculation, Design and Manufacturing Super Short Height Hydraulic Jack, Double Acting, Lifting Capacity of 30 Tons for Lifting Bridge Beam to Replace Bearings","authors":"Nguyen Van Thuyen","doi":"10.14445/23488360/ijme-v10i6p101","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i6p101","url":null,"abstract":"","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":"110 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76031923","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 : 2023-06-30DOI: 10.14445/23488360/ijme-v10i6p103
Nguyen Van Thuyen
- The barrette grab bucket is one of the important devices used in the construction of foundations for bridges and high-rise buildings. The productivity, quality, and construction cost of the pile holes depend on various parameters, such as the shape and size of the excavation bucket, the assembly position of the components on the excavation bucket, and the crawler crane serving the bucket. This article studies the influence of the position of the components on the excavation bucket on the tension force of the crawler crane based on the dynamic analysis of the barrette grab bucket during the excavation process. This helps determine the reasonable parameters of the barrette grab bucket according to the objective function of the minimum tension force of the crawler crane, providing a basis for selecting crawler cranes with appropriate lifting capacity to reduce construction costs.
{"title":"Optimize the Parameters of the Barrette Grab Bucket based on the Objective Function of Minimizing the Tensile Stress of the Smallest Crawler Crane","authors":"Nguyen Van Thuyen","doi":"10.14445/23488360/ijme-v10i6p103","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i6p103","url":null,"abstract":"- The barrette grab bucket is one of the important devices used in the construction of foundations for bridges and high-rise buildings. The productivity, quality, and construction cost of the pile holes depend on various parameters, such as the shape and size of the excavation bucket, the assembly position of the components on the excavation bucket, and the crawler crane serving the bucket. This article studies the influence of the position of the components on the excavation bucket on the tension force of the crawler crane based on the dynamic analysis of the barrette grab bucket during the excavation process. This helps determine the reasonable parameters of the barrette grab bucket according to the objective function of the minimum tension force of the crawler crane, providing a basis for selecting crawler cranes with appropriate lifting capacity to reduce construction costs.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":"152 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77839976","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 : 2023-06-30DOI: 10.14445/23488360/ijme-v10i6p104
Ekong Godwin I, Essien Promise J, Udom Evans J
- This project presents the Effect of Design Parameters on the Discharge of a Single-acting Reciprocating Pump for use in the Mechanical Engineering laboratory of the Akwa Ibom State University (AKSU). The project provides a portable positive displacement pump for demonstrating the movement of fluids in the laboratory. The component consists of a-transparent piston-cylinder assembly, suction pipe, delivery pipe, suction valve, delivery valve, crank, and connecting rod mechanism powered by an electric motor. During the operation of this apparatus, there will be visual movement of the piston during the suction and delivery stroke per each cycle. The pump piston has a diameter of 0.100 m, a stroke length of 0.305 m, and a designed speed of 20 r.p.m. The suction head and delivery are 0.762 m and 1.585 m, respectively. The practical operations were performed, and data was collected. The reciprocating pump principles were applied for the pressure head analysis during the suction and delivery strokes. The parametric analysis carried out includes the acceleration head during the suction stroke at the beginning of the delivery stroke and the pressure head in the middle of the stroke and at the end of the suction stroke. Analyses were performed, and the results indicate a pump discharge of delivery.0008 m3/s with work done by the pump of 18.40 Nm/sec. Further studies were performed for four different piston diameters, stroke lengths, and speeds. The results were used in the computation analysis for the discharge and work done by the pump.
{"title":"The Effect of Design Parameters on the Discharge of a Transparent Cylinder Single-Acting Reciprocating Pump","authors":"Ekong Godwin I, Essien Promise J, Udom Evans J","doi":"10.14445/23488360/ijme-v10i6p104","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i6p104","url":null,"abstract":"- This project presents the Effect of Design Parameters on the Discharge of a Single-acting Reciprocating Pump for use in the Mechanical Engineering laboratory of the Akwa Ibom State University (AKSU). The project provides a portable positive displacement pump for demonstrating the movement of fluids in the laboratory. The component consists of a-transparent piston-cylinder assembly, suction pipe, delivery pipe, suction valve, delivery valve, crank, and connecting rod mechanism powered by an electric motor. During the operation of this apparatus, there will be visual movement of the piston during the suction and delivery stroke per each cycle. The pump piston has a diameter of 0.100 m, a stroke length of 0.305 m, and a designed speed of 20 r.p.m. The suction head and delivery are 0.762 m and 1.585 m, respectively. The practical operations were performed, and data was collected. The reciprocating pump principles were applied for the pressure head analysis during the suction and delivery strokes. The parametric analysis carried out includes the acceleration head during the suction stroke at the beginning of the delivery stroke and the pressure head in the middle of the stroke and at the end of the suction stroke. Analyses were performed, and the results indicate a pump discharge of delivery.0008 m3/s with work done by the pump of 18.40 Nm/sec. Further studies were performed for four different piston diameters, stroke lengths, and speeds. The results were used in the computation analysis for the discharge and work done by the pump.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":"41 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75320058","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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