Pub Date : 2023-03-25DOI: 10.14445/23488360/ijme-v10i3p102
Kannarasu V, H. S, Nallusamy S
{"title":"Design and Analysis of Different Formability Parameters on Single Point Progressive Method","authors":"Kannarasu V, H. S, Nallusamy S","doi":"10.14445/23488360/ijme-v10i3p102","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i3p102","url":null,"abstract":"","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84575745","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 : 2023-03-25DOI: 10.14445/23488360/ijme-v10i3p101
Nallusamy S, S. K, Balaji R
- In the current manufacturing scenario, the Helical Coil Heat Exchangers (HCHE) are produced by three roll bending of pipes resulting in the formation of wrinkles on the inner edges of the pipes. The subject of this work is to compare the heat transfer characteristics and fluid flow behaviour in the wrinkled pipe and ideal pipe HCHE. Computational Fluid Dynamics (CFD) analysis for ideal pipe and wrinkled pipe heat exchangers are carried out to investigate heat transfer and fluid flow behaviour. The methodology of CFD is also validated using theoretical analysis. Constant properties and temperature-dependent properties of fluid passing in the heat exchanger are taken for modelling of CFD calculation. The final results revels that, wrinkled pipes have more heat transfer rate and effectiveness than ideal pipes, head loss is increased due to the presence of wrinkles and the rate of mass flow is reduced in wrinkled pipes due to reduction in volume inside the pipe
{"title":"Examination on Properties of Wrinkled Pipes in Helical Coil Heat Exchangers by CFD","authors":"Nallusamy S, S. K, Balaji R","doi":"10.14445/23488360/ijme-v10i3p101","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i3p101","url":null,"abstract":"- In the current manufacturing scenario, the Helical Coil Heat Exchangers (HCHE) are produced by three roll bending of pipes resulting in the formation of wrinkles on the inner edges of the pipes. The subject of this work is to compare the heat transfer characteristics and fluid flow behaviour in the wrinkled pipe and ideal pipe HCHE. Computational Fluid Dynamics (CFD) analysis for ideal pipe and wrinkled pipe heat exchangers are carried out to investigate heat transfer and fluid flow behaviour. The methodology of CFD is also validated using theoretical analysis. Constant properties and temperature-dependent properties of fluid passing in the heat exchanger are taken for modelling of CFD calculation. The final results revels that, wrinkled pipes have more heat transfer rate and effectiveness than ideal pipes, head loss is increased due to the presence of wrinkles and the rate of mass flow is reduced in wrinkled pipes due to reduction in volume inside the pipe","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90323568","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 : 2023-03-20DOI: 10.1177/03064190231163487
L. Bernardini, E. Di Gialleonardo
In the last decades, novel teaching strategies have been increasingly adopted to improve and enhance the students learning process by promoting their involvement and engagement during classes. In this context, this work presents a laboratory experience proposed to the third-year bachelor students of the course of ‘Mechanics of Vibrations’, held at the faculty of mechanical engineering of Politecnico di Milano. The experience consisted in the presentation of a rotor test bench specifically designed for educational purposes. Main concepts of rotor dynamics were analysed and showed, together with a critical discussion on the discrepancies between the Jeffcott–Laval model and experimental results. This project, that is one of the outcomes of an educational project for post-covid teaching promoted by Politecnico di Milano, involved almost 200 students in total. An anonymous evaluation survey proposed to students revealed a general appreciation of the experience, especially for the possibility of visualising important theoretical concepts. Given the positive feedback, the demonstration will be repeated in the next academic year, with some changes according to students’ suggestions.
{"title":"Active learning approach to enhance rotor dynamics understanding: A classroom demonstration","authors":"L. Bernardini, E. Di Gialleonardo","doi":"10.1177/03064190231163487","DOIUrl":"https://doi.org/10.1177/03064190231163487","url":null,"abstract":"In the last decades, novel teaching strategies have been increasingly adopted to improve and enhance the students learning process by promoting their involvement and engagement during classes. In this context, this work presents a laboratory experience proposed to the third-year bachelor students of the course of ‘Mechanics of Vibrations’, held at the faculty of mechanical engineering of Politecnico di Milano. The experience consisted in the presentation of a rotor test bench specifically designed for educational purposes. Main concepts of rotor dynamics were analysed and showed, together with a critical discussion on the discrepancies between the Jeffcott–Laval model and experimental results. This project, that is one of the outcomes of an educational project for post-covid teaching promoted by Politecnico di Milano, involved almost 200 students in total. An anonymous evaluation survey proposed to students revealed a general appreciation of the experience, especially for the possibility of visualising important theoretical concepts. Given the positive feedback, the demonstration will be repeated in the next academic year, with some changes according to students’ suggestions.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44900923","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 : 2023-03-20DOI: 10.1177/03064190231164049
G.V.S.S. Sharma
With the exposure of the mechanical engineering undergraduate students to the concepts of spatial visualization, this work assesses the effect of spatial visualization skills on the visual thinking abilities. Influence of spatial visualization on visual thinking and cognitive abilities like reasoning, abstract thinking, planning, comprehension of complex ideas, quick learning and learning from experience, is analysed through FMEA (failure modes and effects analysis). The RPNs (risk-priority-numbers) have been calculated and priority is set for proposing the corrective actions. Further to this, case studies in tool design have been picked for exhibition of spatial visualization skill set. Influence of tool design on visual thinking capability of the students is understood through various case-studies. Thus, tool, die and mold design ideation is used as a platform for the proposing improvements in visual thinking and cognitive abilities among mechanical engineering students.
本研究通过对机械工程专业大学生空间可视化概念的接触，考察了空间可视化技能对视觉思维能力的影响。通过FMEA (failure modes and effects analysis)分析空间可视化对视觉思维和认知能力的影响，如推理、抽象思维、规划、对复杂思想的理解、快速学习和从经验中学习。rpn(风险-优先级-编号)已经计算出来，并为提出纠正措施设定了优先级。此外，工具设计的案例研究被挑选出来展示空间可视化技能。通过案例分析，了解工具设计对学生视觉思维能力的影响。因此，工具、模具和模具设计构思是机械工程专业学生视觉思维和认知能力提高的一个平台。
{"title":"Spatial visualization for development of visual thinking and cognitive abilities among mechanical engineering students through tool design ideation","authors":"G.V.S.S. Sharma","doi":"10.1177/03064190231164049","DOIUrl":"https://doi.org/10.1177/03064190231164049","url":null,"abstract":"With the exposure of the mechanical engineering undergraduate students to the concepts of spatial visualization, this work assesses the effect of spatial visualization skills on the visual thinking abilities. Influence of spatial visualization on visual thinking and cognitive abilities like reasoning, abstract thinking, planning, comprehension of complex ideas, quick learning and learning from experience, is analysed through FMEA (failure modes and effects analysis). The RPNs (risk-priority-numbers) have been calculated and priority is set for proposing the corrective actions. Further to this, case studies in tool design have been picked for exhibition of spatial visualization skill set. Influence of tool design on visual thinking capability of the students is understood through various case-studies. Thus, tool, die and mold design ideation is used as a platform for the proposing improvements in visual thinking and cognitive abilities among mechanical engineering students.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41917200","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 : 2023-03-16DOI: 10.1177/03064190231164719
R. Clark, A. Kaw, R. Guldiken
When students repeatedly reflect, it can enhance their metacognitive abilities, including self-regulatory skills of planning, monitoring, and evaluating. In a fluid mechanics course for undergraduates at a large southeastern U.S. university, in-class problem solving in a flipped classroom was coupled with intentional metacognitive skills instruction and repeated reflection to enhance metacognition. The weekly reflective responses were coded by two analysts to identify the recurring themes and uncover evidence of the development and/or reinforcement of self-regulating behaviors for academic management. To enable a comparison, a flipped classroom without the metacognitive instruction and repeated reflection was also implemented (i.e., non-intervention group). The two cohorts completed identical final exams. Based on our preliminary analysis with year one data, a statistically and practically-significant difference between the two cohorts was found with the free-response scores on the final exam in favor of the intervention cohort that had received the metacognitive support (p < 0.0005; Cohen's d = 0.72). Also, the Metacognitive Activities Inventory (MCAI) indicated a significantly-higher positive change in self-regulatory behavior for the intervention cohort (p = 0.001; d = 0.50). Focus groups were conducted to gather students’ perspectives on the reflective activity, with differences found by demographic group. In addition, a significantly higher proportion of females (versus males) viewed the reflections in a positive manner (p = 0.05). Significant associations between themes in the weekly reflections and direct knowledge measures were also uncovered. This included a positive relationship between academic self-management (i.e., diligence and carefulness) and exam performance. Overall, our preliminary results point to a desirable impact of metacognitive instruction and repeated reflection on knowledge outcomes, metacognitive skills, and self-regulatory behaviors.
{"title":"Metacognition instruction and repeated reflection in a fluid mechanics course: Reflective themes and student outcomes","authors":"R. Clark, A. Kaw, R. Guldiken","doi":"10.1177/03064190231164719","DOIUrl":"https://doi.org/10.1177/03064190231164719","url":null,"abstract":"When students repeatedly reflect, it can enhance their metacognitive abilities, including self-regulatory skills of planning, monitoring, and evaluating. In a fluid mechanics course for undergraduates at a large southeastern U.S. university, in-class problem solving in a flipped classroom was coupled with intentional metacognitive skills instruction and repeated reflection to enhance metacognition. The weekly reflective responses were coded by two analysts to identify the recurring themes and uncover evidence of the development and/or reinforcement of self-regulating behaviors for academic management. To enable a comparison, a flipped classroom without the metacognitive instruction and repeated reflection was also implemented (i.e., non-intervention group). The two cohorts completed identical final exams. Based on our preliminary analysis with year one data, a statistically and practically-significant difference between the two cohorts was found with the free-response scores on the final exam in favor of the intervention cohort that had received the metacognitive support (p < 0.0005; Cohen's d = 0.72). Also, the Metacognitive Activities Inventory (MCAI) indicated a significantly-higher positive change in self-regulatory behavior for the intervention cohort (p = 0.001; d = 0.50). Focus groups were conducted to gather students’ perspectives on the reflective activity, with differences found by demographic group. In addition, a significantly higher proportion of females (versus males) viewed the reflections in a positive manner (p = 0.05). Significant associations between themes in the weekly reflections and direct knowledge measures were also uncovered. This included a positive relationship between academic self-management (i.e., diligence and carefulness) and exam performance. Overall, our preliminary results point to a desirable impact of metacognitive instruction and repeated reflection on knowledge outcomes, metacognitive skills, and self-regulatory behaviors.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45650975","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 : 2023-03-03DOI: 10.1177/03064190231161274
João Pedro Severo Foresto, Weliton Soares Martins, Taynara Geysa S. do Lago, Adriano da Silva Marques
Refrigeration and air conditioning systems are essential in residential, commercial, and industrial segments. The data acquisition and the control of equipment results in an improvement in efficiency and a decrease in energy consumption, considering that the data obtained bring a better visualization and understanding of the components of the system. This work aims to automate data acquisition from a vapor compression refrigeration workbench by developing a low-cost data acquisition system. The system was developed using Arduino and LabView with the assistance of LINX software. After the communication between the controller and the program, six thermocouples were installed on the refrigeration workbench to acquire the temperatures in the program of the data acquisition system. For reading system pressure values, a camera was used to capture images from six analog pressure gauges. From reading these data, the pressure-enthalpy diagram of the thermodynamic cycle was obtained. The experimental refrigeration workbench has been used in teaching and research activities. The data acquisition system developed for the refrigeration workbench improved the realization of experiments, allowing a better comparison between experimental and theoretical results.
{"title":"Development of a low-cost data acquisition system for a vapor compression refrigeration experimental workbench","authors":"João Pedro Severo Foresto, Weliton Soares Martins, Taynara Geysa S. do Lago, Adriano da Silva Marques","doi":"10.1177/03064190231161274","DOIUrl":"https://doi.org/10.1177/03064190231161274","url":null,"abstract":"Refrigeration and air conditioning systems are essential in residential, commercial, and industrial segments. The data acquisition and the control of equipment results in an improvement in efficiency and a decrease in energy consumption, considering that the data obtained bring a better visualization and understanding of the components of the system. This work aims to automate data acquisition from a vapor compression refrigeration workbench by developing a low-cost data acquisition system. The system was developed using Arduino and LabView with the assistance of LINX software. After the communication between the controller and the program, six thermocouples were installed on the refrigeration workbench to acquire the temperatures in the program of the data acquisition system. For reading system pressure values, a camera was used to capture images from six analog pressure gauges. From reading these data, the pressure-enthalpy diagram of the thermodynamic cycle was obtained. The experimental refrigeration workbench has been used in teaching and research activities. The data acquisition system developed for the refrigeration workbench improved the realization of experiments, allowing a better comparison between experimental and theoretical results.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45668304","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 : 2023-02-28DOI: 10.14445/23488360/ijme-v10i2p102
Mofreh A. Hashim, Ibrahim R. Teaima
{"title":"Mixing Zone of Single Port Submerged Diffuser with Threaded Outlet for Thermal Discharge from Thermal Power Stations","authors":"Mofreh A. Hashim, Ibrahim R. Teaima","doi":"10.14445/23488360/ijme-v10i2p102","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i2p102","url":null,"abstract":"","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80170643","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 : 2023-02-28DOI: 10.14445/23488360/ijme-v10i2p101
Pankaj Dumka, N. Samaiya, S. Gandhi, Dhananjay R. Mishra
{"title":"Modelling of Hardy Cross Method for Pipe Networks","authors":"Pankaj Dumka, N. Samaiya, S. Gandhi, Dhananjay R. Mishra","doi":"10.14445/23488360/ijme-v10i2p101","DOIUrl":"https://doi.org/10.14445/23488360/ijme-v10i2p101","url":null,"abstract":"","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89365324","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 : 2023-02-28DOI: 10.1177/03064190231160357
R. Moliner-Heredia, J. V. Abellán-Nebot
In engineering courses with a large number of students, fail and dropout rates are usually high even in courses that can be expected to be interesting to the students. Gamification tools have arisen as an interesting way to motivate the students for a real continuous assessment, increasing the student’s attendance and performance. In this paper, a gamification approach based on a Kahoot tool, Moodle activities, and commemorative badges is proposed within a manufacturing course. The designed activities let the students compete among themselves to get the maximum number of points, which will be converted into extra grades that are added to the final exam grade. The gamification experience has been proven to be highly positive according to students’ and instructors’ perceptions, and the average increase of pass rate and course attendance with respect to previous years have increased from 22% to 34% and from 38% to 66%, respectively.
{"title":"Evaluation of the impact of gamification on students’ performance and engagement in manufacturing engineering courses","authors":"R. Moliner-Heredia, J. V. Abellán-Nebot","doi":"10.1177/03064190231160357","DOIUrl":"https://doi.org/10.1177/03064190231160357","url":null,"abstract":"In engineering courses with a large number of students, fail and dropout rates are usually high even in courses that can be expected to be interesting to the students. Gamification tools have arisen as an interesting way to motivate the students for a real continuous assessment, increasing the student’s attendance and performance. In this paper, a gamification approach based on a Kahoot tool, Moodle activities, and commemorative badges is proposed within a manufacturing course. The designed activities let the students compete among themselves to get the maximum number of points, which will be converted into extra grades that are added to the final exam grade. The gamification experience has been proven to be highly positive according to students’ and instructors’ perceptions, and the average increase of pass rate and course attendance with respect to previous years have increased from 22% to 34% and from 38% to 66%, respectively.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47094194","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 : 2023-02-23DOI: 10.1177/03064190231159330
Adrian Stein, Tarik Parcic, T. Singh
Dynamics is a core discipline in Mechanical and Aerospace Engineering programs and with the ubiquitous nature of control in modern-day applications, the field of mechatronics has gained popularity. Mechatronics refers to the field of engineering which integrates the engineering disciplines of mechanical, control, electronics, and computing. To create a testbed to illustrate a tabletop mechatronics system, the paper details the design, and fabrication of an active pendulum whose length can be changed in real-time using solenoids. This permits illustrating two concepts: (1) damping of pendulum oscillations which emulates the sway of a crane and (2) amplification of the oscillations which emulates the pumping of a playground swing. The paper describes the steps prior to experimental validation which includes: modeling, system identification, signal processing, and controller implementation. Numerical simulations are used to prototype the controller and eventually to compare the simulation results to the experimental ones. The results of all the experiments illustrate a close match between the simulated and experimental results. To permit reproduction of the experiment, the design details and code to implement the controllers are posted in a public repository.
{"title":"From playground swings to sway control of cranes: An active pendulum experiment","authors":"Adrian Stein, Tarik Parcic, T. Singh","doi":"10.1177/03064190231159330","DOIUrl":"https://doi.org/10.1177/03064190231159330","url":null,"abstract":"Dynamics is a core discipline in Mechanical and Aerospace Engineering programs and with the ubiquitous nature of control in modern-day applications, the field of mechatronics has gained popularity. Mechatronics refers to the field of engineering which integrates the engineering disciplines of mechanical, control, electronics, and computing. To create a testbed to illustrate a tabletop mechatronics system, the paper details the design, and fabrication of an active pendulum whose length can be changed in real-time using solenoids. This permits illustrating two concepts: (1) damping of pendulum oscillations which emulates the sway of a crane and (2) amplification of the oscillations which emulates the pumping of a playground swing. The paper describes the steps prior to experimental validation which includes: modeling, system identification, signal processing, and controller implementation. Numerical simulations are used to prototype the controller and eventually to compare the simulation results to the experimental ones. The results of all the experiments illustrate a close match between the simulated and experimental results. To permit reproduction of the experiment, the design details and code to implement the controllers are posted in a public repository.","PeriodicalId":39952,"journal":{"name":"International Journal of Mechanical Engineering Education","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48930426","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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