Abstract The synthetic jet actuators are one of the most investigated types of actuators used in heat transfer and active flow control. The energetic efficiency of actuators is a key parameter determining the possibility of device use. The actuators with two or more diaphragms have higher efficiency than the actuators with only one. The paper presents the investigations of the acoustic synthetic jet actuator with two opposite diaphragms. In the paper, synthetic jet velocity, Reynolds number and the energetic efficiency as a function of oscillating actuator frequency, for a different cavity, orifice configuration and one real input power P0 = 2 W were studied. The possibility of theoretical calculation of first and second resonance frequency were checked. The coupling ratio for actuators was calculated. The maximum energetic efficiency was η = 8.67% and Reynolds number Re = 8503. The possibility of using the same dependencies and rules during the design of actuators with two opposite diaphragms as in the case of actuators with one diaphragm was demonstrated. The results may be useful in the design of the actuators of the two membranes.
{"title":"Synthetic jet actuator with two opposite diaphragms","authors":"E. Smyk, S. Wawrzyniak, K. Peszyński","doi":"10.2478/mme-2020-0004","DOIUrl":"https://doi.org/10.2478/mme-2020-0004","url":null,"abstract":"Abstract The synthetic jet actuators are one of the most investigated types of actuators used in heat transfer and active flow control. The energetic efficiency of actuators is a key parameter determining the possibility of device use. The actuators with two or more diaphragms have higher efficiency than the actuators with only one. The paper presents the investigations of the acoustic synthetic jet actuator with two opposite diaphragms. In the paper, synthetic jet velocity, Reynolds number and the energetic efficiency as a function of oscillating actuator frequency, for a different cavity, orifice configuration and one real input power P0 = 2 W were studied. The possibility of theoretical calculation of first and second resonance frequency were checked. The coupling ratio for actuators was calculated. The maximum energetic efficiency was η = 8.67% and Reynolds number Re = 8503. The possibility of using the same dependencies and rules during the design of actuators with two opposite diaphragms as in the case of actuators with one diaphragm was demonstrated. The results may be useful in the design of the actuators of the two membranes.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45205875","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}
Abstract The swash plate type compressor utilized in car air conditioning devices and cooling system was analyzed in this study. Proper dynamic behavior of the components in such a compressor affected the correct functioning of the whole system. The aim of the study was to identify the characteristics of the main motion components in the swash plate–slippers–piston assembly of the compressor and to estimate the friction torques in its bearings. Some models of this assembly are elaborated and presented in the paper. The main components of slipper complex motion were identified, such as reciprocal motion along the axis of piston, rotation around piston axis, and short-time rotation around its own axis. Friction torque in axial bearing was higher than in journal bearing and varied with the rotational angle. Friction torques in journal bearings varied with the rotational angle and had different courses for two bearings of the compressor.
{"title":"The effect of dynamics of the swash plate–slippers–piston assembly on friction torques in bearings in compressor of cooling aggregate","authors":"M. Woźniak, T. Szydłowski, K. Siczek","doi":"10.2478/mme-2020-0006","DOIUrl":"https://doi.org/10.2478/mme-2020-0006","url":null,"abstract":"Abstract The swash plate type compressor utilized in car air conditioning devices and cooling system was analyzed in this study. Proper dynamic behavior of the components in such a compressor affected the correct functioning of the whole system. The aim of the study was to identify the characteristics of the main motion components in the swash plate–slippers–piston assembly of the compressor and to estimate the friction torques in its bearings. Some models of this assembly are elaborated and presented in the paper. The main components of slipper complex motion were identified, such as reciprocal motion along the axis of piston, rotation around piston axis, and short-time rotation around its own axis. Friction torque in axial bearing was higher than in journal bearing and varied with the rotational angle. Friction torques in journal bearings varied with the rotational angle and had different courses for two bearings of the compressor.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41375089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Kurc, A. Burghardt, D. Szybicki, P. Gierlak, Wojciech Łabuński, M. Muszyńska, J. Giergiel
Abstract The article presents an original method of communication and data exchange in a robotic machining station consisting of two robots, a positioner and a 3D optic scanner. The task of one of the robots, equipped with a 3D optic scanner, was to receive point cloud of a detail (mould) attached to the positioner table. After detail digitalisation, the received point cloud was adjusted to (compared with) a model detail in the form of a CAD file in the Atos Professional software. In the software, casting material excesses were received in places selected on the detail. Values of the excesses and their coordinates were saved in the script and sent to the robot controller using TCP/IP protocol. The other of robots, equipped with the force control addition and the option of obtaining various processing tools, received sent excess and its coordinates. The other robot adjusted the processing parameters to random excesses, the value of which was received from measurements of the optic scanner of the first robot.
{"title":"Robotic machining in correlation with a 3D scanner","authors":"K. Kurc, A. Burghardt, D. Szybicki, P. Gierlak, Wojciech Łabuński, M. Muszyńska, J. Giergiel","doi":"10.2478/mme-2020-0003","DOIUrl":"https://doi.org/10.2478/mme-2020-0003","url":null,"abstract":"Abstract The article presents an original method of communication and data exchange in a robotic machining station consisting of two robots, a positioner and a 3D optic scanner. The task of one of the robots, equipped with a 3D optic scanner, was to receive point cloud of a detail (mould) attached to the positioner table. After detail digitalisation, the received point cloud was adjusted to (compared with) a model detail in the form of a CAD file in the Atos Professional software. In the software, casting material excesses were received in places selected on the detail. Values of the excesses and their coordinates were saved in the script and sent to the robot controller using TCP/IP protocol. The other of robots, equipped with the force control addition and the option of obtaining various processing tools, received sent excess and its coordinates. The other robot adjusted the processing parameters to random excesses, the value of which was received from measurements of the optic scanner of the first robot.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49065277","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 article focuses on the synthesis of a steering mechanism that exactly meets the requirements of steering geometry. It starts from reviewing the four-bar linkage, then discusses the number of points that a common four-bar linkage could precisely trace at most. After pointing out the limits of a four-bar steering mechanism, this article investigates the turning geometry for steering wheels and proposes a steering mechanism using servo motors and ARDUINO board. The pitch curves, addendum curves, dedendum curves, tooth profiles and transition curves of the noncircular gears are formulated and designed. Finally, kinematic simulations are executed to demonstrate the target of design
{"title":"Design of Accurate Steering Gear Mechanism","authors":"V. Babu, P. G. Rao, K. S. Rao, B. Krishna","doi":"10.2478/MME-2018-0009","DOIUrl":"https://doi.org/10.2478/MME-2018-0009","url":null,"abstract":"This article focuses on the synthesis of a steering mechanism that exactly meets the requirements of steering geometry. It starts from reviewing the four-bar linkage, then discusses the number of points that a common four-bar linkage could precisely trace at most. After pointing out the limits of a four-bar steering mechanism, this article investigates the turning geometry for steering wheels and proposes a steering mechanism using servo motors and ARDUINO board. The pitch curves, addendum curves, dedendum curves, tooth profiles and transition curves of the noncircular gears are formulated and designed. Finally, kinematic simulations are executed to demonstrate the target of design","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69233512","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}
T. Kannan, B. Kumar, G. Kannan, M. Umar, Mohammad Chand Khan
Abstract This work is aimed at developing relations between the pertinent variables that affect drilling process of stainless steel using artificial neural network. The experiments were conducted on vertical CNC machining centre. The parameters used were spindle speed and feed rate. The effect of machining parameters on entry burr height, exit burr height and surface roughness was experimentally evaluated for different spindle speeds and feed rates. A model was established between the drilling parameters and experimentally obtained data using ANN. The predicted values and measured values are fairly close, which indicates that the developed model can be effectively used to predict the burr height and surface roughness in drilling of stainless steel. Genetic algorithm (GA) technique was used in this work to identify the optimized drilling parameters. Confirmation test was conducted with the optimized parameters and it was found that confirmation test results were similar to that of GA-predicted output values.
{"title":"Application of Genetic Algorithm Technique for Machining Parameters Optimization in Drilling of Stainless Steel","authors":"T. Kannan, B. Kumar, G. Kannan, M. Umar, Mohammad Chand Khan","doi":"10.2478/mme-2019-0036","DOIUrl":"https://doi.org/10.2478/mme-2019-0036","url":null,"abstract":"Abstract This work is aimed at developing relations between the pertinent variables that affect drilling process of stainless steel using artificial neural network. The experiments were conducted on vertical CNC machining centre. The parameters used were spindle speed and feed rate. The effect of machining parameters on entry burr height, exit burr height and surface roughness was experimentally evaluated for different spindle speeds and feed rates. A model was established between the drilling parameters and experimentally obtained data using ANN. The predicted values and measured values are fairly close, which indicates that the developed model can be effectively used to predict the burr height and surface roughness in drilling of stainless steel. Genetic algorithm (GA) technique was used in this work to identify the optimized drilling parameters. Confirmation test was conducted with the optimized parameters and it was found that confirmation test results were similar to that of GA-predicted output values.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45877273","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}
Abstract This paper deals with the study of thermoelastic thin beam in a modified couple stress with three-phase-lag thermoelastic diffusion model subjected to thermal and chemical potential sources. The governing equations are derived by using the Euler-Bernoulli beam assumption and eigenvalue approach. The Laplace transform technique is employed to obtain the expressions for displacements, lateral deflection, temperature change, axial stress and chemical potential. A particular type of instantaneous and distributed sources is taken to show the utility of the approach. The general algorithm of the inverse Laplace transform is developed to compute the results numerically. The numerical results are depicted graphically to show the effects of phase lags, with and without energy dissipation on the resulting quantities. Some special cases are given.
{"title":"Resonance of Nanoscale Beam due to Various Sources in Modified Couple Stress Thermoelastic Diffusion with Phase Lags","authors":"Rajneesh Kumar, S. Devi, Veena Sharma","doi":"10.2478/mme-2019-0006","DOIUrl":"https://doi.org/10.2478/mme-2019-0006","url":null,"abstract":"Abstract This paper deals with the study of thermoelastic thin beam in a modified couple stress with three-phase-lag thermoelastic diffusion model subjected to thermal and chemical potential sources. The governing equations are derived by using the Euler-Bernoulli beam assumption and eigenvalue approach. The Laplace transform technique is employed to obtain the expressions for displacements, lateral deflection, temperature change, axial stress and chemical potential. A particular type of instantaneous and distributed sources is taken to show the utility of the approach. The general algorithm of the inverse Laplace transform is developed to compute the results numerically. The numerical results are depicted graphically to show the effects of phase lags, with and without energy dissipation on the resulting quantities. Some special cases are given.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43476529","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}
Abstract The subject of this article is the finite element method (FEM) simulation of the multi-layered rectangular composite beam subjected to three-point bending test. The study is focused on the composite beams made of glass or carbon fibre-reinforced laminates (glass fibre-reinforced polymer [GFRP] and carbon fibre-reinforced polymer [CFRP]) for which different laminate stacking were addressed. Three beam geometries with various length-to-thickness ratios included short beam shear (SBS) test, provided the beam is short relative to its thickness, which maximised the induced shear stresses. Simulation included the application of Tsai–Hill, Hoffman, Tsai–Wu, Hashin and Puck failure criteria to perform the composite beam failure analysis wherein the matrix and fibre failure were considered separately. Numerical failure studies also aimed to verify the beam failure modes and the participation of stress tensor elements in material failure.
{"title":"Load-carrying capacity of the GFRP and CFRP composite beams subjected to three-point bending test – numerical investigations","authors":"D. Banat","doi":"10.2478/mme-2019-0037","DOIUrl":"https://doi.org/10.2478/mme-2019-0037","url":null,"abstract":"Abstract The subject of this article is the finite element method (FEM) simulation of the multi-layered rectangular composite beam subjected to three-point bending test. The study is focused on the composite beams made of glass or carbon fibre-reinforced laminates (glass fibre-reinforced polymer [GFRP] and carbon fibre-reinforced polymer [CFRP]) for which different laminate stacking were addressed. Three beam geometries with various length-to-thickness ratios included short beam shear (SBS) test, provided the beam is short relative to its thickness, which maximised the induced shear stresses. Simulation included the application of Tsai–Hill, Hoffman, Tsai–Wu, Hashin and Puck failure criteria to perform the composite beam failure analysis wherein the matrix and fibre failure were considered separately. Numerical failure studies also aimed to verify the beam failure modes and the participation of stress tensor elements in material failure.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48968069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Sadat, A. Mokaddem, B. Doumi, M. Berber, A. Boutaous
Abstract In this paper, we have studied the effect of thermal stress on the damage of fiber-matrix interface of a hybrid biocomposite composed of two natural fibers, Hemp, Sisal, and Starch matrix. Our genetic modeling used the nonlinear acoustic technique based on Cox’s analytical model, Weibull’s probabilistic model, and Lebrun’s model describing the thermal stress by the two coefficients of expansion. The stress applied to our representative elementary volume is a uni-axial tensile stress. The numerical simulation shows that the Hemp- Sisal/Starch hybrid biocomposite is most resistant to thermal stresses as compared with Hemp/Starch biocomposite. It also shows that hybrid biocomposite materials have a high resistance to applied stresses (mechanical and thermal) compared to traditional materials and biocomposite materials. The results obtained in our study coincide perfectly with the results of Antoine et al., which showed through experimental tests that natural fibers perfectly improve the mechanical properties of biocomposite materials.
{"title":"Investigation of the effect of thermal stress on the interface damage of hybrid biocomposite materials","authors":"S. Sadat, A. Mokaddem, B. Doumi, M. Berber, A. Boutaous","doi":"10.2478/mme-2019-0034","DOIUrl":"https://doi.org/10.2478/mme-2019-0034","url":null,"abstract":"Abstract In this paper, we have studied the effect of thermal stress on the damage of fiber-matrix interface of a hybrid biocomposite composed of two natural fibers, Hemp, Sisal, and Starch matrix. Our genetic modeling used the nonlinear acoustic technique based on Cox’s analytical model, Weibull’s probabilistic model, and Lebrun’s model describing the thermal stress by the two coefficients of expansion. The stress applied to our representative elementary volume is a uni-axial tensile stress. The numerical simulation shows that the Hemp- Sisal/Starch hybrid biocomposite is most resistant to thermal stresses as compared with Hemp/Starch biocomposite. It also shows that hybrid biocomposite materials have a high resistance to applied stresses (mechanical and thermal) compared to traditional materials and biocomposite materials. The results obtained in our study coincide perfectly with the results of Antoine et al., which showed through experimental tests that natural fibers perfectly improve the mechanical properties of biocomposite materials.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49422829","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}
Abstract Building designers have to think about new strategies to achieve the best sustainable building designs. Well-planned passive solar heating strategies in building design may reduce a building’s energy consumption significantly. In this paper, a proposed design of the south façade of a room by integrating a hybrid solar wall and a window to passively heat a room is studied. The simulations for the three-dimensional model of BIPV Trombe wall system were carried out for December 10th, 2015. The temperature and velocity distribution of indoor air in different positions inside the room are obtained from the simulation results. The obtained results show that the temperature difference between the inlet and the outlet of the solar wall can reach 9°C. The 3D analysis of the proposed model clearly shows that the window’s thermal effect on the passive heating cannot be neglected. Meanwhile, the simulation’s daily electrical efficiency conversion and average indoor air temperature of this system can reach 18% and 28° C, respectively for maximum solar radiation of 470 W/m2.
{"title":"Numerical analysis of the thermal behavior of building integrated hybrid solar wall","authors":"Djelaili Abdelbaki, K. A. Nabil","doi":"10.2478/mme-2019-0020","DOIUrl":"https://doi.org/10.2478/mme-2019-0020","url":null,"abstract":"Abstract Building designers have to think about new strategies to achieve the best sustainable building designs. Well-planned passive solar heating strategies in building design may reduce a building’s energy consumption significantly. In this paper, a proposed design of the south façade of a room by integrating a hybrid solar wall and a window to passively heat a room is studied. The simulations for the three-dimensional model of BIPV Trombe wall system were carried out for December 10th, 2015. The temperature and velocity distribution of indoor air in different positions inside the room are obtained from the simulation results. The obtained results show that the temperature difference between the inlet and the outlet of the solar wall can reach 9°C. The 3D analysis of the proposed model clearly shows that the window’s thermal effect on the passive heating cannot be neglected. Meanwhile, the simulation’s daily electrical efficiency conversion and average indoor air temperature of this system can reach 18% and 28° C, respectively for maximum solar radiation of 470 W/m2.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45142215","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}
Abstract The typical cryogenic condenser described here transfers the refrigerating effect from its inner side to its outer side through the wall of the condenser. The separate close refrigeration cycle operates on Reverse Stirling Cycle using hydrogen or helium as working fluid. The nitrogen gas gets liquefied when it comes in contact with the cold outer surface of the condenser. We have successfully developed a cryogenic condenser using copper of electrolytic grade for a liquefaction duty of 10 liters of liquid nitrogen per hour. Condenser effectiveness is evaluated by assembling it in Cryogenerator model, ZIF-1002 and by noting the liquefaction rate. Both the results are satisfactory. Selection of material, fabrication, testing of the condenser developed for a Cryogenerator have been described in the paper to assess its suitability for a Cryogenerator based on Reverse Stirling cycle liquefier.
{"title":"Development of a cryogenic condenser and computation of its heat transfer efficiency based on liquefaction of nitrogen gas","authors":"D. R. Chowdhury, N. Chakraborty, S. Sarkar","doi":"10.2478/mme-2019-0039","DOIUrl":"https://doi.org/10.2478/mme-2019-0039","url":null,"abstract":"Abstract The typical cryogenic condenser described here transfers the refrigerating effect from its inner side to its outer side through the wall of the condenser. The separate close refrigeration cycle operates on Reverse Stirling Cycle using hydrogen or helium as working fluid. The nitrogen gas gets liquefied when it comes in contact with the cold outer surface of the condenser. We have successfully developed a cryogenic condenser using copper of electrolytic grade for a liquefaction duty of 10 liters of liquid nitrogen per hour. Condenser effectiveness is evaluated by assembling it in Cryogenerator model, ZIF-1002 and by noting the liquefaction rate. Both the results are satisfactory. Selection of material, fabrication, testing of the condenser developed for a Cryogenerator have been described in the paper to assess its suitability for a Cryogenerator based on Reverse Stirling cycle liquefier.","PeriodicalId":53557,"journal":{"name":"Mechanics and Mechanical Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47060003","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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