Pub Date : 2012-04-10DOI: 10.1109/ISMA.2012.6215183
H. Nounou, M. Nounou
The objective of this work is to develop adaptive control schemes to establish asymptotic closed-loop stabilization for a class of uncertain time-delay systems with time-varying delays and nonlinear dynamical perturbations. The plant parameter uncertainties are assumed to be parametric and norm-bounded, and the norm of the nonlinear perturbation is assumed to be bounded by a weighted norm of the state. Two main problems are investigated. In the first problem, an adaptive control scheme is developed to guarantee asymptotic closed-loop stabilization when the weight of the state norm is assumed to be known. In the second problem, however, the weight of the state norm is assumed to be unknown. The stability results are demonstrated via a continuous stirred tank reactor (CSTR) system.
{"title":"Adaptive control of nonlinear time-delay systems and application to a chemical reactor","authors":"H. Nounou, M. Nounou","doi":"10.1109/ISMA.2012.6215183","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215183","url":null,"abstract":"The objective of this work is to develop adaptive control schemes to establish asymptotic closed-loop stabilization for a class of uncertain time-delay systems with time-varying delays and nonlinear dynamical perturbations. The plant parameter uncertainties are assumed to be parametric and norm-bounded, and the norm of the nonlinear perturbation is assumed to be bounded by a weighted norm of the state. Two main problems are investigated. In the first problem, an adaptive control scheme is developed to guarantee asymptotic closed-loop stabilization when the weight of the state norm is assumed to be known. In the second problem, however, the weight of the state norm is assumed to be unknown. The stability results are demonstrated via a continuous stirred tank reactor (CSTR) system.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125497837","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215178
M. Qasim, S. Hoda, M. Al Zaabi, N. Mahdi, G. Gopakumar, S. Abu Rahma, A. El-Hag, A. Yeşildirek
This paper discusses the details of designing and building a monitoring system that can be used to evaluate the status of power system apparatus remotely. The monitoring system was built and tested to monitor both the partial discharge inside a transformer model and the leakage current on an outdoor insulator's surface. The monitoring system is designed to measure different parameters and hence to evaluate the status of the power system apparatus and display them in real time. Moreover, the system will also send email notifications which keep the utility engineer informed regarding the status of the power system apparatus at all times.
{"title":"Remote monitoring of power system apparatus in the context of smart grid","authors":"M. Qasim, S. Hoda, M. Al Zaabi, N. Mahdi, G. Gopakumar, S. Abu Rahma, A. El-Hag, A. Yeşildirek","doi":"10.1109/ISMA.2012.6215178","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215178","url":null,"abstract":"This paper discusses the details of designing and building a monitoring system that can be used to evaluate the status of power system apparatus remotely. The monitoring system was built and tested to monitor both the partial discharge inside a transformer model and the leakage current on an outdoor insulator's surface. The monitoring system is designed to measure different parameters and hence to evaluate the status of the power system apparatus and display them in real time. Moreover, the system will also send email notifications which keep the utility engineer informed regarding the status of the power system apparatus at all times.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121063573","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215186
M. Jaradat, Mohammad I. Awad, B. El-Khasawneh
A Genetic-Fuzzy Sliding Mode Controller is presented for DC Servomotor system control. The fuzzy logic controller was optimized by Genetic Algorithm method to reduce and eliminate the chattering phenomenon. To demonstrate the effectiveness of the presented approach, a comparison between the proposed system, and standard Sliding Mode controller were conducted. Simulation results have shown the advantages of choosing the proposed controller, to achieve the desired results, regardless of the external disturbance, the variation in system parameters, or the feedback noise.
{"title":"Genetic-Fuzzy Sliding Mode Controller for a DC Servomotor system","authors":"M. Jaradat, Mohammad I. Awad, B. El-Khasawneh","doi":"10.1109/ISMA.2012.6215186","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215186","url":null,"abstract":"A Genetic-Fuzzy Sliding Mode Controller is presented for DC Servomotor system control. The fuzzy logic controller was optimized by Genetic Algorithm method to reduce and eliminate the chattering phenomenon. To demonstrate the effectiveness of the presented approach, a comparison between the proposed system, and standard Sliding Mode controller were conducted. Simulation results have shown the advantages of choosing the proposed controller, to achieve the desired results, regardless of the external disturbance, the variation in system parameters, or the feedback noise.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116974825","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215177
J. Pascal
Proceedings of the 8th International Symposium on Mechatronics and its Applications (ISMA12)1, Sharjah, UAE. The purpose of this work is to show that the principle of smooth fit can fail even for convex problems. Using the dynamic programming approach which involves using differential equation methods, we get the value function for a convex optimal control problem. Then this value function turns out to be a convex viscosity solution of the dynamic programming equation, not C2 along the free boundary, and hence not a classical solution of the above mentioned equation.
{"title":"On the principle of smooth fit for some convex optimal control problems","authors":"J. Pascal","doi":"10.1109/ISMA.2012.6215177","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215177","url":null,"abstract":"Proceedings of the 8th International Symposium on Mechatronics and its Applications (ISMA12)1, Sharjah, UAE. The purpose of this work is to show that the principle of smooth fit can fail even for convex problems. Using the dynamic programming approach which involves using differential equation methods, we get the value function for a convex optimal control problem. Then this value function turns out to be a convex viscosity solution of the dynamic programming equation, not C2 along the free boundary, and hence not a classical solution of the above mentioned equation.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124083232","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215164
E. Poorreza, R. H. Vafaie, M. Mehdipoor, A. Pourmand, H. B. Ghavifekr
Particle separation is a challenge by highly miniaturized channel systems. Due to very low Reynolds number of buffer fluid, microseparators based on travelling wave dielectrophoresis effect have a good sufficiency in such applications. In this paper a microchannel technique based on surface micromachining is modified to a microseparator. Due to fabrication process the electrodes made of highly doped polysilicon are covered by a thin silicon-nitride layer. The influence of this thin isolating layer on functionality of the microseparator is investigated. The simulation results indicate that a satisfied separation occurs in the frequency range of 1MHz, when electrical conductivity of buffer fluid is lower than 1μs/m. The fabrication process is presented and influences of other parameters such as permittivity of fluid and bias voltage on the operation of separator are discussed.
{"title":"A novel miniaturized travelling wave dielectrophoresis microseparator for lab-on-a-chip applications","authors":"E. Poorreza, R. H. Vafaie, M. Mehdipoor, A. Pourmand, H. B. Ghavifekr","doi":"10.1109/ISMA.2012.6215164","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215164","url":null,"abstract":"Particle separation is a challenge by highly miniaturized channel systems. Due to very low Reynolds number of buffer fluid, microseparators based on travelling wave dielectrophoresis effect have a good sufficiency in such applications. In this paper a microchannel technique based on surface micromachining is modified to a microseparator. Due to fabrication process the electrodes made of highly doped polysilicon are covered by a thin silicon-nitride layer. The influence of this thin isolating layer on functionality of the microseparator is investigated. The simulation results indicate that a satisfied separation occurs in the frequency range of 1MHz, when electrical conductivity of buffer fluid is lower than 1μs/m. The fabrication process is presented and influences of other parameters such as permittivity of fluid and bias voltage on the operation of separator are discussed.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125820192","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215168
D. Belloli, S. Savaresi, A. Cologni, F. Previdi, D. Cazzola
In this paper, the modeling and the control design problems for a Internal Bubble Cooling (IBC) system are considered. A dynamic model has been developed using a physical approach and validated with experimental measurement. The model has been used to design the closed-loop control architecture to regulated the bubble diameter. The controller has been tuned by simulation and its effectiveness has been verified with experimental tests.
{"title":"Modeling and control of an Internal Bubble Cooling system","authors":"D. Belloli, S. Savaresi, A. Cologni, F. Previdi, D. Cazzola","doi":"10.1109/ISMA.2012.6215168","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215168","url":null,"abstract":"In this paper, the modeling and the control design problems for a Internal Bubble Cooling (IBC) system are considered. A dynamic model has been developed using a physical approach and validated with experimental measurement. The model has been used to design the closed-loop control architecture to regulated the bubble diameter. The controller has been tuned by simulation and its effectiveness has been verified with experimental tests.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127574478","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215179
R. H. Vafaie, M. Mehdipoor, A. Pourmand, E. Poorreza, H. B. Ghavifekr
Miniaturization of microchannels leads to low Reynolds number flow. In such a case, electroosmotic force is the best choice to perturb fluid. Due to low Reynolds number, mixing process is one of the major problems in the Lab-On-a-Chip (LOC) or micro Total Analysis Systems (μ-TAS). This paper proposes a novel technique of microchannel fabrication based on surface micromachining, the technology process needs to cover the exciting electrodes by an insulator layer. A more miniaturized electroosmotically actuated micromixer is designed using a novel sinusoidal-shaped electrode patterns to induce chaotic regime. During the fabrication process a sinusoidal-shaped electrode patterns are covered by a thin silicon nitride layer as an insulator layer. Result reveals that the micromixer is able to perturb the low Reynolds number flow, as well as the silicon nitride layer can reduce the high voltage gradient at the sharp corners and edges of the electrodes. The influence of excitation and geometrical parameters on mixing quality is investigated.
{"title":"A modified electroosmotic micromixer for highly miniaturized microchannels","authors":"R. H. Vafaie, M. Mehdipoor, A. Pourmand, E. Poorreza, H. B. Ghavifekr","doi":"10.1109/ISMA.2012.6215179","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215179","url":null,"abstract":"Miniaturization of microchannels leads to low Reynolds number flow. In such a case, electroosmotic force is the best choice to perturb fluid. Due to low Reynolds number, mixing process is one of the major problems in the Lab-On-a-Chip (LOC) or micro Total Analysis Systems (μ-TAS). This paper proposes a novel technique of microchannel fabrication based on surface micromachining, the technology process needs to cover the exciting electrodes by an insulator layer. A more miniaturized electroosmotically actuated micromixer is designed using a novel sinusoidal-shaped electrode patterns to induce chaotic regime. During the fabrication process a sinusoidal-shaped electrode patterns are covered by a thin silicon nitride layer as an insulator layer. Result reveals that the micromixer is able to perturb the low Reynolds number flow, as well as the silicon nitride layer can reduce the high voltage gradient at the sharp corners and edges of the electrodes. The influence of excitation and geometrical parameters on mixing quality is investigated.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131341987","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215169
H. Mirzajani, Mojtaba Mohammadi Nasiri, H. B. Ghavifekr
A new micromachined wideband frequency reconfigurable microstrip patch antenna is demonstrated in this paper. The tunable antenna system is fabricated by a combination of surface and bulk micromachining processes. Thermal actuation is employed to precisely adjust the operating frequency with voltage ranges compatible with today's CMOS circuitries. A bulk micromachined silicon membrane containing thermal actuators serves as a platform for antenna patch. The patch is excited by a 50Ω feed line through proximity coupling. The out-of-plane motion of the thermal actuators normal to the antenna surface deflects the patch downward respect to the fixed ground plane. This deflection reduces the air gap height between the antenna patch and feed line and consequently, resonant frequency of the antenna. The effect of initial air gap height on achievable tuning range and bandwidth of the antenna is also investigated and the optimum range is presented. The up-state operating frequency of the antenna is 22.61GHz which continuously can be lowered to 22.17GHz. A tuning range of 440MHz was achieved by a CMOS compatible actuation voltage of 1.5V. The bandwidth of the antenna for up and down-state positions are 1.34 and 1.27GHz respectively. The RF performance of the antenna and its mechanical behavior is investigated by FEM analysis and satisfactory results are obtained within the tuning range.
{"title":"A new design of MEMS-based wideband frequency reconfigurable microstrip patch antenna","authors":"H. Mirzajani, Mojtaba Mohammadi Nasiri, H. B. Ghavifekr","doi":"10.1109/ISMA.2012.6215169","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215169","url":null,"abstract":"A new micromachined wideband frequency reconfigurable microstrip patch antenna is demonstrated in this paper. The tunable antenna system is fabricated by a combination of surface and bulk micromachining processes. Thermal actuation is employed to precisely adjust the operating frequency with voltage ranges compatible with today's CMOS circuitries. A bulk micromachined silicon membrane containing thermal actuators serves as a platform for antenna patch. The patch is excited by a 50Ω feed line through proximity coupling. The out-of-plane motion of the thermal actuators normal to the antenna surface deflects the patch downward respect to the fixed ground plane. This deflection reduces the air gap height between the antenna patch and feed line and consequently, resonant frequency of the antenna. The effect of initial air gap height on achievable tuning range and bandwidth of the antenna is also investigated and the optimum range is presented. The up-state operating frequency of the antenna is 22.61GHz which continuously can be lowered to 22.17GHz. A tuning range of 440MHz was achieved by a CMOS compatible actuation voltage of 1.5V. The bandwidth of the antenna for up and down-state positions are 1.34 and 1.27GHz respectively. The RF performance of the antenna and its mechanical behavior is investigated by FEM analysis and satisfactory results are obtained within the tuning range.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134009221","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215166
B. El-Khasawneh
Hybrid serial-parallel link manipulators combine the advantages and eliminate disadvantages of their ancestors the pure parallel or serial kinematics manipulators. The particular type of hybrid machine shown in this paper consists of two planar three degrees-of-freedom manipulators assembled together in a special configuration. This paper developed the kinematic analysis of this mechanism, namely the inverse and forward kinematics of these manipulators. Furthermore, this paper developed a calibration model for this type of manipulators, and calibration model results were very promising. A graphical tool was developed to assist user in visualizing postures and for solving the different kinematics problems.
{"title":"The kinematics and calibration of a 5 degrees-of-freedom hybrid serial-parallel kinematics manipulator","authors":"B. El-Khasawneh","doi":"10.1109/ISMA.2012.6215166","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215166","url":null,"abstract":"Hybrid serial-parallel link manipulators combine the advantages and eliminate disadvantages of their ancestors the pure parallel or serial kinematics manipulators. The particular type of hybrid machine shown in this paper consists of two planar three degrees-of-freedom manipulators assembled together in a special configuration. This paper developed the kinematic analysis of this mechanism, namely the inverse and forward kinematics of these manipulators. Furthermore, this paper developed a calibration model for this type of manipulators, and calibration model results were very promising. A graphical tool was developed to assist user in visualizing postures and for solving the different kinematics problems.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130275229","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 : 2012-04-10DOI: 10.1109/ISMA.2012.6215200
K. Saadeddin, M. Abdel-Hafez, M. Jarrah
In this paper, a low-cost navigation system with high integrity and reliability is proposed for enhancing highway traffic safety in adverse weather situations, such as a foggy or rainy weather. A high-integrity, 15-state, estimation filter is proposed to obtain a high accuracy state estimate. The filter utilizes a vehicle velocity constraint measurement to enhance the accuracy of the estimate. Two estimations filters, the Kalman filter (KF) and the information filter (IF), are designed and compared to obtain the estimate of the vehicle state. An instrumentation system that consists of a microcontroller, a GPS receiver, an IMU, encoders, and a Zigbee transceiver is constructed. The microcontroller provides a vehicle navigation solution at 50 Hz by fusing the measurements of the IMU, the GPS receiver and the digital compass using the proposed filter design. Experimental tests, using the proposed system, are conducted and the obtained results are presented. These results are processed with and without the velocity constraints. The estimation accuracy improvement with the addition of the velocity constraints is demonstrated. Also, results of a static test are used to assess the accuracy of the low-cost navigation systems against a commercial solution.
{"title":"Low-cost, high-accuracy, state estimation for vehicle collision prevention system","authors":"K. Saadeddin, M. Abdel-Hafez, M. Jarrah","doi":"10.1109/ISMA.2012.6215200","DOIUrl":"https://doi.org/10.1109/ISMA.2012.6215200","url":null,"abstract":"In this paper, a low-cost navigation system with high integrity and reliability is proposed for enhancing highway traffic safety in adverse weather situations, such as a foggy or rainy weather. A high-integrity, 15-state, estimation filter is proposed to obtain a high accuracy state estimate. The filter utilizes a vehicle velocity constraint measurement to enhance the accuracy of the estimate. Two estimations filters, the Kalman filter (KF) and the information filter (IF), are designed and compared to obtain the estimate of the vehicle state. An instrumentation system that consists of a microcontroller, a GPS receiver, an IMU, encoders, and a Zigbee transceiver is constructed. The microcontroller provides a vehicle navigation solution at 50 Hz by fusing the measurements of the IMU, the GPS receiver and the digital compass using the proposed filter design. Experimental tests, using the proposed system, are conducted and the obtained results are presented. These results are processed with and without the velocity constraints. The estimation accuracy improvement with the addition of the velocity constraints is demonstrated. Also, results of a static test are used to assess the accuracy of the low-cost navigation systems against a commercial solution.","PeriodicalId":315018,"journal":{"name":"2012 8th International Symposium on Mechatronics and its Applications","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134034775","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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