In this paper, we investigate the numerical approximation solution of parabolic and hyperbolic equations with variable coefficients and different boundary conditions using the space-time localized collocation method based on the radial basis function. The method is based on transforming the original d -dimensional problem in space into d + 1 -dimensional one in the space-time domain by combining the d -dimensional vector space variable and 1 -dimensional time variable in one d + 1 -dimensional variable vector. The advantages of such formulation are (i) time discretization as implicit, explicit, θ -method, method-of-line approach, and others are not applied; (ii) the time stability analysis is not discussed; and (iii) recomputation of the resulting matrix at each time level as done for other methods for solving partial differential equations (PDEs) with variable coefficients is avoided and the matrix is computed once. Two different formulations of the d -dimensional problem as a d + 1 -dimensional space-time one are discussed based on the type of PDEs considered. The localized radial basis function meshless method is applied to seek for the numerical solution. Different examples in two and three-dimensional space are solved to show the accuracy of such method. Different types of boundary conditions, Neumann and Dirichlet, are also considered for parabolic and hyperbolic equations to show the sensibility of the method in respect to boundary conditions. A comparison to the fourth-order Runge-Kutta method is also investigated.
{"title":"Solving Parabolic and Hyperbolic Equations with Variable Coefficients Using Space-Time Localized Radial Basis Function Collocation Method","authors":"Mohammed Hamaidi, A. Naji, A. Taik","doi":"10.1155/2021/6688806","DOIUrl":"https://doi.org/10.1155/2021/6688806","url":null,"abstract":"In this paper, we investigate the numerical approximation solution of parabolic and hyperbolic equations with variable coefficients and different boundary conditions using the space-time localized collocation method based on the radial basis function. The method is based on transforming the original \u0000 \u0000 d\u0000 \u0000 -dimensional problem in space into \u0000 \u0000 \u0000 \u0000 d\u0000 +\u0000 1\u0000 \u0000 \u0000 \u0000 -dimensional one in the space-time domain by combining the \u0000 \u0000 d\u0000 \u0000 -dimensional vector space variable and \u0000 \u0000 1\u0000 \u0000 -dimensional time variable in one \u0000 \u0000 \u0000 \u0000 d\u0000 +\u0000 1\u0000 \u0000 \u0000 \u0000 -dimensional variable vector. The advantages of such formulation are (i) time discretization as implicit, explicit, \u0000 \u0000 θ\u0000 \u0000 -method, method-of-line approach, and others are not applied; (ii) the time stability analysis is not discussed; and (iii) recomputation of the resulting matrix at each time level as done for other methods for solving partial differential equations (PDEs) with variable coefficients is avoided and the matrix is computed once. Two different formulations of the \u0000 \u0000 d\u0000 \u0000 -dimensional problem as a \u0000 \u0000 \u0000 \u0000 d\u0000 +\u0000 1\u0000 \u0000 \u0000 \u0000 -dimensional space-time one are discussed based on the type of PDEs considered. The localized radial basis function meshless method is applied to seek for the numerical solution. Different examples in two and three-dimensional space are solved to show the accuracy of such method. Different types of boundary conditions, Neumann and Dirichlet, are also considered for parabolic and hyperbolic equations to show the sensibility of the method in respect to boundary conditions. A comparison to the fourth-order Runge-Kutta method is also investigated.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"2015 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2021-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86889707","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}
{"title":"Corrigendum to “Eulerian Oil Spills Model Using Finite-Volume Method with Moving Boundary and Wet-Dry Fronts”","authors":"Ehsan Sarhadizadeh, K. Hejazi","doi":"10.1155/2021/6418926","DOIUrl":"https://doi.org/10.1155/2021/6418926","url":null,"abstract":"<jats:p />","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"258 1","pages":"1-1"},"PeriodicalIF":3.2,"publicationDate":"2021-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77075033","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}
Qing-feng Liu, B. Šavija, J. Xia, Xiaoshan Lin, D. Hou
{"title":"Modelling and Simulation for Concrete Durability: Mechanism and Prediction","authors":"Qing-feng Liu, B. Šavija, J. Xia, Xiaoshan Lin, D. Hou","doi":"10.1155/2021/9782710","DOIUrl":"https://doi.org/10.1155/2021/9782710","url":null,"abstract":"<jats:p />","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"139 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73199544","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}
Yuzhong Wang, M. Wei, Xue Hu, Minghong Jiang, Lixin Zhang
It is a promising heat supply strategy to use induction heating for the pipe lining process, but temperature control is hindering its application. In this study, we designed the variable universe fuzzy PID controller, and the lining induction heating system model was used to verify its performance. First, the transfer function parameters of the lining induction heating system are obtained by the step response method. Then, a point-by-point convergent interpolator is established through the contraction-expansion factors to realize the adaptive expansion of the fuzzy universe. Finally, the performance of PID, fuzzy PID, and variable universe fuzzy PID are compared through simulation experiments, and the ability of the controller to resist disturbance is verified by adding interference. The results show that the variable universe fuzzy PID controller can greatly improve the performance of fuzzy PID in response speed and settle time. The average stability error is smaller than PID and fuzzy PID control. It can meet the speed and accuracy requirements of the lining induction heating system. This research can be used as a reference for induction heating precise control and evidence that the variable universe fuzzy PID control can satisfy the lining induction heating process.
{"title":"Research on Variable Universe Fuzzy PID Control Strategy of Pipe Lining Induction Heating System","authors":"Yuzhong Wang, M. Wei, Xue Hu, Minghong Jiang, Lixin Zhang","doi":"10.1155/2020/8852943","DOIUrl":"https://doi.org/10.1155/2020/8852943","url":null,"abstract":"It is a promising heat supply strategy to use induction heating for the pipe lining process, but temperature control is hindering its application. In this study, we designed the variable universe fuzzy PID controller, and the lining induction heating system model was used to verify its performance. First, the transfer function parameters of the lining induction heating system are obtained by the step response method. Then, a point-by-point convergent interpolator is established through the contraction-expansion factors to realize the adaptive expansion of the fuzzy universe. Finally, the performance of PID, fuzzy PID, and variable universe fuzzy PID are compared through simulation experiments, and the ability of the controller to resist disturbance is verified by adding interference. The results show that the variable universe fuzzy PID controller can greatly improve the performance of fuzzy PID in response speed and settle time. The average stability error is smaller than PID and fuzzy PID control. It can meet the speed and accuracy requirements of the lining induction heating system. This research can be used as a reference for induction heating precise control and evidence that the variable universe fuzzy PID control can satisfy the lining induction heating process.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"32 1","pages":"1-9"},"PeriodicalIF":3.2,"publicationDate":"2020-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77431466","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}
M. Hssikou, Y. Elguennouni, Jamal Baliti, M. Alaoui
Natural convection of gas flow (air) confined within an enclosed square-section cavity is investigated numerically using the lattice Boltzmann method (LBM). The right (left) side of the enclosure is partially heated (cooled) by a hot (cold) chip, while the left (right) one is completely kept at cold (hot) temperature. However, the horizontal walls and vertical parts near the chip are kept adiabatic. The buoyancy effect induced by the gravity acceleration, related to the convection force, is evaluated through the Rayleigh number in the range of (laminar regime). The wall heating-ratio effect on the flow properties such as temperature and velocity profiles was examined. The heat transfer is analyzed through the Nusselt number for different chip lengths. Results show that the wall heat ratio has an interesting effect on the flow behavior. Results show good agreement with those of full natural convection in the literature, experimental, and simulation data.
{"title":"Heat Transfer of Gas Flow within a Partially Heated or Cooled Square Cavity","authors":"M. Hssikou, Y. Elguennouni, Jamal Baliti, M. Alaoui","doi":"10.1155/2020/8886682","DOIUrl":"https://doi.org/10.1155/2020/8886682","url":null,"abstract":"Natural convection of gas flow (air) confined within an enclosed square-section cavity is investigated numerically using the lattice Boltzmann method (LBM). The right (left) side of the enclosure is partially heated (cooled) by a hot (cold) chip, while the left (right) one is completely kept at cold (hot) temperature. However, the horizontal walls and vertical parts near the chip are kept adiabatic. The buoyancy effect induced by the gravity acceleration, related to the convection force, is evaluated through the Rayleigh number in the range of (laminar regime). The wall heating-ratio effect on the flow properties such as temperature and velocity profiles was examined. The heat transfer is analyzed through the Nusselt number for different chip lengths. Results show that the wall heat ratio has an interesting effect on the flow behavior. Results show good agreement with those of full natural convection in the literature, experimental, and simulation data.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"51 1","pages":"1-11"},"PeriodicalIF":3.2,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78059406","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}
A social force (SF) model is proposed to simulate the egress of pedestrians while smoke is spreading. The advection-diffusion with source term is used to describe the propagation of smoke. It is incorporated into the SF model. The navigation field in our model is determined by the negative gradient of the solution of the Eikonal equation. It depends on the pedestrian and smoke density. Numerical experiments are performed in a room with multiple exits, and their results are shown.
{"title":"A Social Force Model for Pedestrians’ Movements Affected by Smoke Spreading","authors":"J. Makmul","doi":"10.1155/2020/8819076","DOIUrl":"https://doi.org/10.1155/2020/8819076","url":null,"abstract":"A social force (SF) model is proposed to simulate the egress of pedestrians while smoke is spreading. The advection-diffusion with source term is used to describe the propagation of smoke. It is incorporated into the SF model. The navigation field in our model is determined by the negative gradient of the solution of the Eikonal equation. It depends on the pedestrian and smoke density. Numerical experiments are performed in a room with multiple exits, and their results are shown.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"29 1","pages":""},"PeriodicalIF":3.2,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81432224","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 research is looking for three laminated composite material groups. These three groups were utilized in experimental investigation to find their mechanical properties. These properties have been used to design and manufacture a socket for a partial foot prosthesis using an ANSYS model. This socket was manufactured with a vacuum pressure device to improve its properties. The socket composite material was tested for tensile and fatigue properties; then, its results were used in the ANSYS model. The composite material matrix was laminated in an 80 : 20 ratio, and there were three types of reinforcement lamination material (Perlon, glass fiber, and carbon fiber). The mechanical property results of these tests were found as follows: using onlyPerlon reinforcement, the properties are σy = 33:6MPa, σult = 35:6MPa, and modulus of elasticity = 1:03GPa; using (3Perlon +2carbon fiber +3perlon) layers, the properties were σy = 65:5MPa, σult = 92:5MPa, and modulus of elasticity = 1:99GPa; and using (3Perlon + 2 glass fiber + 3perlon) layers, the results were σy = 40MPa, σult = 46:6MPa, and modulus of elasticity = 1:4 GPa. The ANSYS model used the boundary condition from the measured contact pressure between the socket and the patient’s stump. The MatScan (F-socket) pressure sensor utilized these interface pressure measurements. The maximum values for the pressure were found as follows: 190 kPa and 164 kPa, which are recorded in the posterior and lateral locations, respectively. The calculated factor of safety for the prosthesis that has been made from a selected composite material with the following layers (3 Perlon+2 carbon fiber+3 Perlon) is 1.037 which is safe for design prosthetic applications. From this study, more prosthetic designs can be modelled and manufactured using this approach. Prosthetics and orthotics are usually custom-made for each patient according to its specific requirements. So, it will be very helpful to find a procedure to analyze the prosthetics before manufacturing it.
{"title":"Fatigue Characteristics and Numerical Modelling Prosthetic for Chopart Amputation","authors":"S. M. Abbas, Ammar I. Kubba","doi":"10.1155/2020/4752479","DOIUrl":"https://doi.org/10.1155/2020/4752479","url":null,"abstract":"This research is looking for three laminated composite material groups. These three groups were utilized in experimental investigation to find their mechanical properties. These properties have been used to design and manufacture a socket for a partial foot prosthesis using an ANSYS model. This socket was manufactured with a vacuum pressure device to improve its properties. The socket composite material was tested for tensile and fatigue properties; then, its results were used in the ANSYS model. The composite material matrix was laminated in an 80 : 20 ratio, and there were three types of reinforcement lamination material (Perlon, glass fiber, and carbon fiber). The mechanical property results of these tests were found as follows: using onlyPerlon reinforcement, the properties are σy = 33:6MPa, σult = 35:6MPa, and modulus of elasticity = 1:03GPa; using (3Perlon +2carbon fiber +3perlon) layers, the properties were σy = 65:5MPa, σult = 92:5MPa, and modulus of elasticity = 1:99GPa; and using (3Perlon + 2 glass fiber + 3perlon) layers, the results were σy = 40MPa, σult = 46:6MPa, and modulus of elasticity = 1:4 GPa. The ANSYS model used the boundary condition from the measured contact pressure between the socket and the patient’s stump. The MatScan (F-socket) pressure sensor utilized these interface pressure measurements. The maximum values for the pressure were found as follows: 190 kPa and 164 kPa, which are recorded in the posterior and lateral locations, respectively. The calculated factor of safety for the prosthesis that has been made from a selected composite material with the following layers (3 Perlon+2 carbon fiber+3 Perlon) is 1.037 which is safe for design prosthetic applications. From this study, more prosthetic designs can be modelled and manufactured using this approach. Prosthetics and orthotics are usually custom-made for each patient according to its specific requirements. So, it will be very helpful to find a procedure to analyze the prosthetics before manufacturing it.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"37 1","pages":"1-10"},"PeriodicalIF":3.2,"publicationDate":"2020-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79110434","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}
Hicham Aziz, M. Moubadir, A. Farkhsi, N. Amar Touhami
This paper presents the conception and realization of a 2D antenna array using periodic leaky-wave antenna (PLWA) and the binomial array (BA) at 6 GHz as the application of WLAN. The series array of periodic leaky-wave antenna was provided by an array of five rectangular Patches connected by cross lines. The nonuniform amplitudes of the binomial array are used to reduce the sidelobe level; in this way, the center source radiates strongly on the broadside. The prototype of the proposed 2D antenna array is designed, fabricated, and tested. A good agreement is obtained between simulated and measurement results.
{"title":"Sidelobe Suppression in Array-Pattern Synthesis Using Periodic Leaky-Wave Antenna and Binomial Array","authors":"Hicham Aziz, M. Moubadir, A. Farkhsi, N. Amar Touhami","doi":"10.1155/2020/6201767","DOIUrl":"https://doi.org/10.1155/2020/6201767","url":null,"abstract":"This paper presents the conception and realization of a 2D antenna array using periodic leaky-wave antenna (PLWA) and the binomial array (BA) at 6 GHz as the application of WLAN. The series array of periodic leaky-wave antenna was provided by an array of five rectangular Patches connected by cross lines. The nonuniform amplitudes of the binomial array are used to reduce the sidelobe level; in this way, the center source radiates strongly on the broadside. The prototype of the proposed 2D antenna array is designed, fabricated, and tested. A good agreement is obtained between simulated and measurement results.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"19 6 1","pages":"1-6"},"PeriodicalIF":3.2,"publicationDate":"2020-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78035415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The basic relationships among gear ratios, velocity succession, torque directions, power ratios, energy losses, and efficiency are derived from first principles. The techniques presented here can be applied to ordinary, planetary, or mixed gear trains. Also, these techniques provide more insight into how power is flowing through the different parts of the mechanism. Power flow relationships are a helpful tool to study power amplification and power circulation in multipath transmissions. They also provide more insight into how the gear pair entities (GPEs) or gear train entities (GTEs) affect total power losses and allow immediate derivation of the overall efficiency. A representative two-input mechanism is analyzed to demonstrate the effectiveness of improved techniques. The theoretical results are compared with experimental data of previous work. The theoretical and experimental curves exhibit identical trends with a distinct jump in friction loss. The jump is explained by a change in the way of the power flow through the mechanism. The conditions under which power circulation occurs are determined. The results have important implications for understanding how to improve the efficiency of multipath power flow systems.
{"title":"Power Flow Simulation for Two-Degree-of-Freedom Planetary Gear Transmissions with Experimental Validation","authors":"H. A. Hussen, E. L. Esmail, Rahman A. Hussen","doi":"10.1155/2020/8837605","DOIUrl":"https://doi.org/10.1155/2020/8837605","url":null,"abstract":"The basic relationships among gear ratios, velocity succession, torque directions, power ratios, energy losses, and efficiency are derived from first principles. The techniques presented here can be applied to ordinary, planetary, or mixed gear trains. Also, these techniques provide more insight into how power is flowing through the different parts of the mechanism. Power flow relationships are a helpful tool to study power amplification and power circulation in multipath transmissions. They also provide more insight into how the gear pair entities (GPEs) or gear train entities (GTEs) affect total power losses and allow immediate derivation of the overall efficiency. A representative two-input mechanism is analyzed to demonstrate the effectiveness of improved techniques. The theoretical results are compared with experimental data of previous work. The theoretical and experimental curves exhibit identical trends with a distinct jump in friction loss. The jump is explained by a change in the way of the power flow through the mechanism. The conditions under which power circulation occurs are determined. The results have important implications for understanding how to improve the efficiency of multipath power flow systems.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"7 1","pages":"1-14"},"PeriodicalIF":3.2,"publicationDate":"2020-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82400923","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}
O. Olabode, D. Alaigba, Daniel Oramabo, O. Bamigboye
In this project, low-salinity water flooding has been modeled on ECLIPSE black oil simulator in three cases for a total field production life of twenty-five years. In the first case, low-salinity water flooding starts fifteen years after secondary water flooding. For the second case, low-salinity water flooding starts five years after secondary water flooding and runs till the end of the field production life. For the third case, low-salinity water flooding starts five years after secondary water flooding, but low-salinity water flooding is injected in measured pore volumes for a short period of time; then, high-salinity water flooding was resumed till the end of the field production life. This was done to measure the effect of low-salinity water flooding as slug injection. From the three cases presented, oil recovery efficiency, field oil production rate, and field water cut were observed. Increased percentages of 22.66%, 35.12%, and 26.77% were observed in the three cases, respectively.
{"title":"Modelling Low-Salinity Water Flooding as a Tertiary Oil Recovery Technique","authors":"O. Olabode, D. Alaigba, Daniel Oramabo, O. Bamigboye","doi":"10.1155/2020/6485826","DOIUrl":"https://doi.org/10.1155/2020/6485826","url":null,"abstract":"In this project, low-salinity water flooding has been modeled on ECLIPSE black oil simulator in three cases for a total field production life of twenty-five years. In the first case, low-salinity water flooding starts fifteen years after secondary water flooding. For the second case, low-salinity water flooding starts five years after secondary water flooding and runs till the end of the field production life. For the third case, low-salinity water flooding starts five years after secondary water flooding, but low-salinity water flooding is injected in measured pore volumes for a short period of time; then, high-salinity water flooding was resumed till the end of the field production life. This was done to measure the effect of low-salinity water flooding as slug injection. From the three cases presented, oil recovery efficiency, field oil production rate, and field water cut were observed. Increased percentages of 22.66%, 35.12%, and 26.77% were observed in the three cases, respectively.","PeriodicalId":45541,"journal":{"name":"Modelling and Simulation in Engineering","volume":"32 3 1","pages":"1-9"},"PeriodicalIF":3.2,"publicationDate":"2020-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77466662","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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