Kazykhan Rysgul, Tashev Azat, Aitbayeva Rakhatay, Kudaykulov Anarbay, Kunelbayev Murat, M. Arshidinova, Zhunusova Aliya, Kazangapova Bayan
The article describes computational algorithms for estimating the law of distribution of body temperature in the form of a rectangular parallelepiped. The case is studied when a conditioned temperature is maintained on one of the boundaries of a rectangular parallelepiped, and heat exchange with the environment occurs on the opposite side. In addition, there are cases when other faces of the parallelepiped are thermally insulated or are under the influence of the environment. A polynomial is chosen as the approximating function. In accordance with the proposed layout, a function is formed that considers temperature, heat exchange with the environment, and insulation of the faces of a rectangular parallelepiped. The temperatures at the nodal points are determined by minimizing the function. Further, the temperature distribution law is determined according to the proposed approximating polynomial. The estimation of temperature distribution law is calculated for different amounts of partitioning into elements of a rectangular parallelepiped.
{"title":"Development of Methods and Computational Algorithms Parallelepiped in the Presence of Temperature and Heat Exchange","authors":"Kazykhan Rysgul, Tashev Azat, Aitbayeva Rakhatay, Kudaykulov Anarbay, Kunelbayev Murat, M. Arshidinova, Zhunusova Aliya, Kazangapova Bayan","doi":"10.46300/9104.2023.17.9","DOIUrl":"https://doi.org/10.46300/9104.2023.17.9","url":null,"abstract":"The article describes computational algorithms for estimating the law of distribution of body temperature in the form of a rectangular parallelepiped. The case is studied when a conditioned temperature is maintained on one of the boundaries of a rectangular parallelepiped, and heat exchange with the environment occurs on the opposite side. In addition, there are cases when other faces of the parallelepiped are thermally insulated or are under the influence of the environment. A polynomial is chosen as the approximating function. In accordance with the proposed layout, a function is formed that considers temperature, heat exchange with the environment, and insulation of the faces of a rectangular parallelepiped. The temperatures at the nodal points are determined by minimizing the function. Further, the temperature distribution law is determined according to the proposed approximating polynomial. The estimation of temperature distribution law is calculated for different amounts of partitioning into elements of a rectangular parallelepiped.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42952590","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}
Estimation of road traffic noise is fundamental for the health of people living in urban areas, and it is usually assessed based on field-measured data. Real data may not always be available, anyway, and for this reason, predictive models play an important role in the evaluation and controlling of the noise impact. In this contribution, the authors present a multilinear regressive model calibrated on simulated noise levels instead that on real measured ones, correlating percentile noise levels to independent traffic variables. The model efficiency is then evaluated on two field measurement datasets by analyzing data statistics and error metrics. Results show that the model provides good results in terms of mean error (less than 1 dBA on average) even if slight underestimations and overestimations are present. The presented model, then, can be used to assess the impact of road traffic noise anytime field measurements are not available, or even predict it when designing new road infrastructures.
{"title":"Road Traffic Noise Predictions by means of L10 Modelling with a Multilinear Regression Calibrated on Simulated Data","authors":"Domenico Rossi, A. Mascolo, C. Guarnaccia","doi":"10.46300/9104.2023.17.8","DOIUrl":"https://doi.org/10.46300/9104.2023.17.8","url":null,"abstract":"Estimation of road traffic noise is fundamental for the health of people living in urban areas, and it is usually assessed based on field-measured data. Real data may not always be available, anyway, and for this reason, predictive models play an important role in the evaluation and controlling of the noise impact. In this contribution, the authors present a multilinear regressive model calibrated on simulated noise levels instead that on real measured ones, correlating percentile noise levels to independent traffic variables. The model efficiency is then evaluated on two field measurement datasets by analyzing data statistics and error metrics. Results show that the model provides good results in terms of mean error (less than 1 dBA on average) even if slight underestimations and overestimations are present. The presented model, then, can be used to assess the impact of road traffic noise anytime field measurements are not available, or even predict it when designing new road infrastructures.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42767967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the present investigation, a study of the drying kinetics of lateritic mineral samples is carried out and the adjustment of the theoretical models exposed in the specialized literature with the data obtained during the experimentation is evaluated. The variation of humidity, drying speed, and drying time for temperatures between 100 ºC and 500ºC were analyzed. In addition, for each of the temperatures studied, the adjustment constants of the theoretical models were determined. From the comparison of the theoretical models, it is established that the Modified Page model is more adjusted to the behavior obtained from the lateritic mineral. From the analysis of the drying curves, it is concluded that the lateritic mineral has a non-hygroscopic behavior.
{"title":"Experimental Models of the Lateritic Minerals Drying Kinetics at High Temperatures","authors":"Torres Tamayo Enrique, Zalazar Carlos, Morales-Álvarez José, Carrión Daniel, Iza Edison, Reinoso Edgar, Góngora Ever","doi":"10.46300/9104.2023.17.7","DOIUrl":"https://doi.org/10.46300/9104.2023.17.7","url":null,"abstract":"In the present investigation, a study of the drying kinetics of lateritic mineral samples is carried out and the adjustment of the theoretical models exposed in the specialized literature with the data obtained during the experimentation is evaluated. The variation of humidity, drying speed, and drying time for temperatures between 100 ºC and 500ºC were analyzed. In addition, for each of the temperatures studied, the adjustment constants of the theoretical models were determined. From the comparison of the theoretical models, it is established that the Modified Page model is more adjusted to the behavior obtained from the lateritic mineral. From the analysis of the drying curves, it is concluded that the lateritic mineral has a non-hygroscopic behavior.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42830562","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}
Scientific research is devoted to the problem of diagnosing damage in the blades of gas turbine engines in non-stationary conditions. The paper proposes a model for a more accurate calculation of the parameters of the crack detection system using a system of capsules, inside of which, under the influence of pressure, there is a substance exhibiting ionizing properties. In the study, the relations for determining the uneven pressure due to the action of centrifugal tensile forces during the rotation of the turbine blade are obtained. The relations for calculating the minimum required diameter of the capsule to ensure the rupture of the capsule when cracks are opened for the effective operation of the crack detection system are obtained. Calculations of the pressure inside the capsule and the geometry of the capsule at different speeds of rotation of the turbine blade are carried out. An estimate of the error in calculating the pressure inside the capsule is given in the case of not taking into account the action of centrifugal forces. The obtained dependences will significantly optimize the system for detecting damage to turbine blades, and increase the efficiency and safety of the operation of gas turbine engines.
{"title":"Optimization Model of the Shell Capsules Geometry for a System for Diagnosing Damage to Gas Turbine Blades in Non-stationary","authors":"I. Andrianov, Elena K. Chepurnova","doi":"10.46300/9104.2023.17.6","DOIUrl":"https://doi.org/10.46300/9104.2023.17.6","url":null,"abstract":"Scientific research is devoted to the problem of diagnosing damage in the blades of gas turbine engines in non-stationary conditions. The paper proposes a model for a more accurate calculation of the parameters of the crack detection system using a system of capsules, inside of which, under the influence of pressure, there is a substance exhibiting ionizing properties. In the study, the relations for determining the uneven pressure due to the action of centrifugal tensile forces during the rotation of the turbine blade are obtained. The relations for calculating the minimum required diameter of the capsule to ensure the rupture of the capsule when cracks are opened for the effective operation of the crack detection system are obtained. Calculations of the pressure inside the capsule and the geometry of the capsule at different speeds of rotation of the turbine blade are carried out. An estimate of the error in calculating the pressure inside the capsule is given in the case of not taking into account the action of centrifugal forces. The obtained dependences will significantly optimize the system for detecting damage to turbine blades, and increase the efficiency and safety of the operation of gas turbine engines.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47789917","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}
At the initial design stage, there is a problem of determining the thicknesses of the load-bearing elements of an aircraft structure made of composite materials. The paper presents the intelligent design of the composite caisson structural strength. Intelligent design is based on the finite element method. The task of optimization used the objective function of minimum mass and setting some constraints including no types of buckling al-lowed. In optimization, the parameter is the thickness of the element, which changes in the process of minimizing the objective function for elements made of PCM by an amount equal to the thickness of the package. The results show the strength margins of spar webs and rib webs of the caisson of vertical empennage torsion box satisfy the safety factor design.
{"title":"Designing of Aircraft Reinforced Carbon- Composite Torsion Boxes","authors":"A. Bolshikh","doi":"10.46300/9104.2023.17.4","DOIUrl":"https://doi.org/10.46300/9104.2023.17.4","url":null,"abstract":"At the initial design stage, there is a problem of determining the thicknesses of the load-bearing elements of an aircraft structure made of composite materials. The paper presents the intelligent design of the composite caisson structural strength. Intelligent design is based on the finite element method. The task of optimization used the objective function of minimum mass and setting some constraints including no types of buckling al-lowed. In optimization, the parameter is the thickness of the element, which changes in the process of minimizing the objective function for elements made of PCM by an amount equal to the thickness of the package. The results show the strength margins of spar webs and rib webs of the caisson of vertical empennage torsion box satisfy the safety factor design.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42466902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, the optimization values for several double circular tubes filled with foam under dynamic bending loading are compared. The thin-walled tube is frequently used in vehicle construction, especially on the door sill, to reduce impact. Double circular tubes made of the aluminum alloy AA6063 T6 were filled with foam for this numerical study. Structures are modeled and analyzed using the ABAQUS algorithm. Optimization of tubes determined using Non-Dominated Sorting Genetic Algorithm version II (NSGA II). Excellent agreement between the results of the simulation and the empirically validated FE model has been attained. Also, It was found that a double circular tube filled with foam absorbs more energy than one that is empty of foam. Hence, it can be recommended that this structure be used as an energyabsorbing part, such as a door sill, for pure electric vehicles (PEV).
{"title":"Optimization of Foam Filled Door Sill for Pure Electric Vehicle","authors":"F. Djamaluddin","doi":"10.46300/9104.2023.17.5","DOIUrl":"https://doi.org/10.46300/9104.2023.17.5","url":null,"abstract":"In this work, the optimization values for several double circular tubes filled with foam under dynamic bending loading are compared. The thin-walled tube is frequently used in vehicle construction, especially on the door sill, to reduce impact. Double circular tubes made of the aluminum alloy AA6063 T6 were filled with foam for this numerical study. Structures are modeled and analyzed using the ABAQUS algorithm. Optimization of tubes determined using Non-Dominated Sorting Genetic Algorithm version II (NSGA II). Excellent agreement between the results of the simulation and the empirically validated FE model has been attained. Also, It was found that a double circular tube filled with foam absorbs more energy than one that is empty of foam. Hence, it can be recommended that this structure be used as an energyabsorbing part, such as a door sill, for pure electric vehicles (PEV).","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70492005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to improve the efficiency of mechanical weeding and reduce the injury rate caused by work. This paper improves the shortage of traditional weeding machinery, and designs a new combined mechanical weeding device by optimizing the internal structure and increasing the operation function. In this device, the structure of the cutter tooth is optimized and the operation function is added. Secondly, the effect of the weeding is further enhanced by increasing the flame nozzle. Finally, the finite element analysis of the blade and the nozzle is carried out by CFD and COMSOL software, and the rationality of the improvement is explained. The field weeding test showed that the average weeding rate of the machine was 86% and the rate of injured seedlings was 3.5% under the conditions of different advancing speed (0.5, 1, 1.5m/s) and the soil depth of the weeding wheel (3, 6, and 9cm). According to the speed and width of the machine, the efficiency of the machine is 0.7~2hm2/h. The collection performance and operation efficiency meet the technical requirements of weeding operation in dry field machinery. Through the comparison test of mechanical weeding, heat weeding and the effect of combined mechanical weeding, the efficiency of combined mechanical weeding in the test area is higher than that of other weeding methods. This study can provide a reference for the effect of weeds treatment on the dry field weeding machine.
{"title":"Design and Test of a New Type of Coupling Weeder","authors":"Peng Guan, Jianqi Yang","doi":"10.46300/9104.2023.17.3","DOIUrl":"https://doi.org/10.46300/9104.2023.17.3","url":null,"abstract":"In order to improve the efficiency of mechanical weeding and reduce the injury rate caused by work. This paper improves the shortage of traditional weeding machinery, and designs a new combined mechanical weeding device by optimizing the internal structure and increasing the operation function. In this device, the structure of the cutter tooth is optimized and the operation function is added. Secondly, the effect of the weeding is further enhanced by increasing the flame nozzle. Finally, the finite element analysis of the blade and the nozzle is carried out by CFD and COMSOL software, and the rationality of the improvement is explained. The field weeding test showed that the average weeding rate of the machine was 86% and the rate of injured seedlings was 3.5% under the conditions of different advancing speed (0.5, 1, 1.5m/s) and the soil depth of the weeding wheel (3, 6, and 9cm). According to the speed and width of the machine, the efficiency of the machine is 0.7~2hm2/h. The collection performance and operation efficiency meet the technical requirements of weeding operation in dry field machinery. Through the comparison test of mechanical weeding, heat weeding and the effect of combined mechanical weeding, the efficiency of combined mechanical weeding in the test area is higher than that of other weeding methods. This study can provide a reference for the effect of weeds treatment on the dry field weeding machine.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43394880","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}
Unlike welding, soldering does not involve melting the work pieces. Soldering is a process in which two or more items are joined together by melting and putting a filler metal (solder) into the joint. Failure in the solder joint may make the system components lose their functions. Electrical wiring and electronic components are joined to devices and printed circuit boards using soldering. Soldering and brazing are both used in the assembly of musical instruments. Lead-tin alloy solder employed in the current investigation which has a diameter of 4 mm and a density of 11.0103 kg/m3 with continuous heat flux heating from the domain's left side and complete insulation on the other side. The melting of PCM was simulated using the ANSYS (Fluent) melting model. Three procedures were followed during the heating stage of the reflow process to perform the melting heat-transfer analysis. The simulation's results were recorded at regular intervals of 15 seconds. The results show melting rate increases as time proceeds. It is almost the same at the initial stages and increases in the middle and the end of the melting process. Heat transfer happens mostly through conduction during the first 0–30 seconds of the melting process, changing to natural convection as the material continues to heat up.
{"title":"CFD Investigation of the Soldering Process for a Small Spherical PCM Made of Lead-tin Alloy","authors":"M. S. Abood, Ammar Ghany","doi":"10.46300/9104.2023.17.1","DOIUrl":"https://doi.org/10.46300/9104.2023.17.1","url":null,"abstract":"Unlike welding, soldering does not involve melting the work pieces. Soldering is a process in which two or more items are joined together by melting and putting a filler metal (solder) into the joint. Failure in the solder joint may make the system components lose their functions. Electrical wiring and electronic components are joined to devices and printed circuit boards using soldering. Soldering and brazing are both used in the assembly of musical instruments. Lead-tin alloy solder employed in the current investigation which has a diameter of 4 mm and a density of 11.0103 kg/m3 with continuous heat flux heating from the domain's left side and complete insulation on the other side. The melting of PCM was simulated using the ANSYS (Fluent) melting model. Three procedures were followed during the heating stage of the reflow process to perform the melting heat-transfer analysis. The simulation's results were recorded at regular intervals of 15 seconds. The results show melting rate increases as time proceeds. It is almost the same at the initial stages and increases in the middle and the end of the melting process. Heat transfer happens mostly through conduction during the first 0–30 seconds of the melting process, changing to natural convection as the material continues to heat up.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46613731","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}
Mechanisms are significant in mechanical engineering as they are required for proper motion transition. This work studies the kinematic analysis of the planar mechanisms using constraint properties between links and joints. A joint library has been built by two types of joints (revolute and prismatic) and has been modeled to be extended in the future. The Kinematic Analysis of General Planer Mechanisms (KAGPM) has been described and implemented through the Graphical User Interface in MATLAB. The Newton-Raphson method was utilized as a numerically computational technique to resolve the kinematic constraint equations. The proposed KAGPM program has been in the kinematic analysis of a slider crank mechanism for the purpose of validation with Haug. For more validation of the program, the effects of some effective parameters have been investigated (the geometric of the mechanism, the initial conditions, and the transient of the mechanism).
{"title":"Kinematic Analysis of Constrained General Planner Mechanisms Using MATLAB Graphical User Interface (GUI)","authors":"M. William, M. Hegaze, M. El-Sebah, Y. Elshaer","doi":"10.46300/9104.2023.17.2","DOIUrl":"https://doi.org/10.46300/9104.2023.17.2","url":null,"abstract":"Mechanisms are significant in mechanical engineering as they are required for proper motion transition. This work studies the kinematic analysis of the planar mechanisms using constraint properties between links and joints. A joint library has been built by two types of joints (revolute and prismatic) and has been modeled to be extended in the future. The Kinematic Analysis of General Planer Mechanisms (KAGPM) has been described and implemented through the Graphical User Interface in MATLAB. The Newton-Raphson method was utilized as a numerically computational technique to resolve the kinematic constraint equations. The proposed KAGPM program has been in the kinematic analysis of a slider crank mechanism for the purpose of validation with Haug. For more validation of the program, the effects of some effective parameters have been investigated (the geometric of the mechanism, the initial conditions, and the transient of the mechanism).","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48770406","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 : 2022-12-22DOI: 10.46300/9104.2022.16.16
Seongjin Oh, J. Jeong
Commercial vehicles have a higher center of gravity than passenger vehicles, so the rollover rate is higher. In particular, overloading has the effect of further raising the center of gravity, causing rollover even at small lateral acceleration. In this study, we propose a system that identifies and recommends trucks that can safely drive on curved roads by finding factors that cause vehicle rollover through cargo information and driving conditions. It is expected that drivers will be able to transport more safely by preventing overloading, and users will be able to reduce transportation costs by reducing the occurrence of errors in vehicle selection.
{"title":"Design and Simulation of Safe Truck-Cargo Matching System for Rollover Prevention","authors":"Seongjin Oh, J. Jeong","doi":"10.46300/9104.2022.16.16","DOIUrl":"https://doi.org/10.46300/9104.2022.16.16","url":null,"abstract":"Commercial vehicles have a higher center of gravity than passenger vehicles, so the rollover rate is higher. In particular, overloading has the effect of further raising the center of gravity, causing rollover even at small lateral acceleration. In this study, we propose a system that identifies and recommends trucks that can safely drive on curved roads by finding factors that cause vehicle rollover through cargo information and driving conditions. It is expected that drivers will be able to transport more safely by preventing overloading, and users will be able to reduce transportation costs by reducing the occurrence of errors in vehicle selection.","PeriodicalId":39203,"journal":{"name":"International Journal of Mechanics","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46545721","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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