Pub Date : 2021-12-20DOI: 10.1109/scc53769.2021.9768356
Gharbi Abdelaziz, Hamdi Hichem, Ben Regaya Chiheb, Gharbi Rached
Photovoltaic modules are very sensitive to the reduction of solar irradiation due to shading. Shading can be caused by a fixed obstacle (wall, tree or even a simple pillar) or in case of circumstantial events (cloudy sky or covered with heavy smoke or dust). In order to illustrate the influence of shading on the behaviour of a photovoltaic device, a study using MatLab Simulink was carried out on a polycrystalline silicon module YL250P29. The degradation of the incident solar irradiation on a single cell of the photovoltaic panel leads to a considerable decrease in the power produced by the system (about 1/3 in the case of a fully shaded cell). We have monitored the behaviour of the bypass diode, and the pivotal role it plays in preserving the series of cells adjacent to the affected one and ensuring a reasonable rate of output.
{"title":"Shading effect on the performance of a photovoltaic panel","authors":"Gharbi Abdelaziz, Hamdi Hichem, Ben Regaya Chiheb, Gharbi Rached","doi":"10.1109/scc53769.2021.9768356","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768356","url":null,"abstract":"Photovoltaic modules are very sensitive to the reduction of solar irradiation due to shading. Shading can be caused by a fixed obstacle (wall, tree or even a simple pillar) or in case of circumstantial events (cloudy sky or covered with heavy smoke or dust). In order to illustrate the influence of shading on the behaviour of a photovoltaic device, a study using MatLab Simulink was carried out on a polycrystalline silicon module YL250P29. The degradation of the incident solar irradiation on a single cell of the photovoltaic panel leads to a considerable decrease in the power produced by the system (about 1/3 in the case of a fully shaded cell). We have monitored the behaviour of the bypass diode, and the pivotal role it plays in preserving the series of cells adjacent to the affected one and ensuring a reasonable rate of output.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125686910","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768352
Ramzi Bouzaiene, S. Hafsi, F. Bouani
In this paper, we are interested in adaptive neural PID control with a reference model for nonlinear systems. A recurrent neural network architecture is studied, and its parameters are computed to mimic a conventional PID controller. Two neural networks architectures, Feed Forward Neural Network (FFNN) and Recurrent Neural Network (RNN) are used for modeling nonlinear systems. To avoid the errors of the Jacobian system approximation, it is best to model the system with a neural network called an emulator. By adding an emulator in parallel with the dynamic system model, the emulator will be trained to learn the dynamics of the system.The back-propagation method is used as the basis for developing algorithms capable of modeling and controlling our nonlinear systems.
{"title":"Adaptive neural network PID controller for nonlinear systems","authors":"Ramzi Bouzaiene, S. Hafsi, F. Bouani","doi":"10.1109/scc53769.2021.9768352","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768352","url":null,"abstract":"In this paper, we are interested in adaptive neural PID control with a reference model for nonlinear systems. A recurrent neural network architecture is studied, and its parameters are computed to mimic a conventional PID controller. Two neural networks architectures, Feed Forward Neural Network (FFNN) and Recurrent Neural Network (RNN) are used for modeling nonlinear systems. To avoid the errors of the Jacobian system approximation, it is best to model the system with a neural network called an emulator. By adding an emulator in parallel with the dynamic system model, the emulator will be trained to learn the dynamics of the system.The back-propagation method is used as the basis for developing algorithms capable of modeling and controlling our nonlinear systems.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125959722","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768388
Slah Farhani, Haytham Grissa, F. Bacha
Conversion of solar energy to hydrogen has been identified as a viable solution for renewable energy development known as solar fuel. In this article, electric models for a proton exchange membrane (PEM) electrolyzer and a solar panel are used to develop a Simulink diagram. I-V characteristics for a single PEM electrolyser cell and solar photovoltaic are modeled in steady state and produced using an equivalent electrical circuit. The design of a Photo-Voltaic system to generate the electrical energy required to produce 25 kg of Hydrogen per day highlights the potential future of green hydrogen produced from solar energy using photovoltaic systems. This hydrogen gas power station requires the installation of PV system to produce of electrical energy per day to run the Proton Exchange Membrane electrolyser during 5 hours per day. The produced hydrogen can be used to charge fuel cell vehicles, generate electricity for buildings during in the night or transported to be consumed in any other industrial applications.
{"title":"Hydrogen Production Station Using Solar Energy","authors":"Slah Farhani, Haytham Grissa, F. Bacha","doi":"10.1109/scc53769.2021.9768388","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768388","url":null,"abstract":"Conversion of solar energy to hydrogen has been identified as a viable solution for renewable energy development known as solar fuel. In this article, electric models for a proton exchange membrane (PEM) electrolyzer and a solar panel are used to develop a Simulink diagram. I-V characteristics for a single PEM electrolyser cell and solar photovoltaic are modeled in steady state and produced using an equivalent electrical circuit. The design of a Photo-Voltaic system to generate the electrical energy required to produce 25 kg of Hydrogen per day highlights the potential future of green hydrogen produced from solar energy using photovoltaic systems. This hydrogen gas power station requires the installation of PV system to produce of electrical energy per day to run the Proton Exchange Membrane electrolyser during 5 hours per day. The produced hydrogen can be used to charge fuel cell vehicles, generate electricity for buildings during in the night or transported to be consumed in any other industrial applications.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129222011","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768384
Fethi Messaoudi, Fethi Farhani, A. Zaafouri
The demand of PV energy is constantly increasing as renewable and clean energy. But this energy has a challenge such the gain on power in order to improve its efficiency. For this challenge, MPPT methods are obligation in the field of PV system to maximize power output and ensure conversion efficiency. The most common problems associated with MPPT methods are low tracking efficiency, which require more transient time and steady state of oscillations. This paper presents a summary of the widespread MPPT methods with rigorous classification. Also, a comparative recapitulation is made via well-chosen criteria so that the researcher makes the right choice of the appropriate MPPT method.
{"title":"Overview and comparatif of maximum power point tracking methods of PV power system","authors":"Fethi Messaoudi, Fethi Farhani, A. Zaafouri","doi":"10.1109/scc53769.2021.9768384","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768384","url":null,"abstract":"The demand of PV energy is constantly increasing as renewable and clean energy. But this energy has a challenge such the gain on power in order to improve its efficiency. For this challenge, MPPT methods are obligation in the field of PV system to maximize power output and ensure conversion efficiency. The most common problems associated with MPPT methods are low tracking efficiency, which require more transient time and steady state of oscillations. This paper presents a summary of the widespread MPPT methods with rigorous classification. Also, a comparative recapitulation is made via well-chosen criteria so that the researcher makes the right choice of the appropriate MPPT method.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114470212","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768351
Mehdi Mrad, Tamer G. Ali, Ali Balma, A. Gharbi, Ali Samhan, M. Louly
We address the problematic of cutting m rectangular items from a two-dimensional strip. Each item has a given width, height, and demand. The purpose is to minimize the height of the used strip, while respecting the two stages of guillotine cuts. We consider the arc-flow formulation for this NP-hard problem and propose to enhance it using graph compression techniques. Computational results on real-world data show a consistently promising impact of the graph compression in terms of computation time and graph size.
{"title":"Impact of Graph Compression on Solving the Two-Dimensional Strip Cutting Problem","authors":"Mehdi Mrad, Tamer G. Ali, Ali Balma, A. Gharbi, Ali Samhan, M. Louly","doi":"10.1109/scc53769.2021.9768351","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768351","url":null,"abstract":"We address the problematic of cutting m rectangular items from a two-dimensional strip. Each item has a given width, height, and demand. The purpose is to minimize the height of the used strip, while respecting the two stages of guillotine cuts. We consider the arc-flow formulation for this NP-hard problem and propose to enhance it using graph compression techniques. Computational results on real-world data show a consistently promising impact of the graph compression in terms of computation time and graph size.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115292980","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768394
S. B. Salem, Neila Ouerghemmi, K. Bacha, A. Chaari
In this work a fault signature based on the Park Lissajou’s curve is suggested. It was applied to an induction machine driving a centrifugal fan, that operating in various industrial systems. We propose a new index extracted from Park Lissajou’s curve for the detection and localization of unbalanced voltages. In fact, the range ratio is determined to distinguish the two states; normal (balanced voltage) and faulty (unbalanced voltage). The ellipse orientation angle α is calculated to differentiate between the unbalance in phases B and C. This approach is simple, it shows its effectiveness and its robustness in detecting and localizing of studied fault.
{"title":"Detection and Localization of Supply Voltage Unbalance Using an Improved Park Lissajou’s Curves Approach","authors":"S. B. Salem, Neila Ouerghemmi, K. Bacha, A. Chaari","doi":"10.1109/scc53769.2021.9768394","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768394","url":null,"abstract":"In this work a fault signature based on the Park Lissajou’s curve is suggested. It was applied to an induction machine driving a centrifugal fan, that operating in various industrial systems. We propose a new index extracted from Park Lissajou’s curve for the detection and localization of unbalanced voltages. In fact, the range ratio is determined to distinguish the two states; normal (balanced voltage) and faulty (unbalanced voltage). The ellipse orientation angle α is calculated to differentiate between the unbalance in phases B and C. This approach is simple, it shows its effectiveness and its robustness in detecting and localizing of studied fault.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126939709","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768364
M. Belkin, L. Zhukov
We propose a new solution to design a microwave-photonics transceiving hardware for fifth-generation telecom systems of combined Radio-over-Fiber architecture that are considered as a very promising approach for millimeter-wave mobile front hauling, in particular for prospective fixed small cells in metropolitan areas and moving cells in high-speed railways. The contribution describes the layout of the transceiver under study that uses optically injection locked LW-VCSEL simultaneously operating as direct modulated laser and resonant cavity enhanced photodetector, and the results of its experimental investigation to characterize the static and dynamic features in free-running or optical injection-locked modes, and small-signal gain vs RF frequency characteristics for downlink and uplink channels.
{"title":"OIL-VCSEL-Based Microwave-Photonics Transceiver for a Millimeter-Wave Fronthaul","authors":"M. Belkin, L. Zhukov","doi":"10.1109/scc53769.2021.9768364","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768364","url":null,"abstract":"We propose a new solution to design a microwave-photonics transceiving hardware for fifth-generation telecom systems of combined Radio-over-Fiber architecture that are considered as a very promising approach for millimeter-wave mobile front hauling, in particular for prospective fixed small cells in metropolitan areas and moving cells in high-speed railways. The contribution describes the layout of the transceiver under study that uses optically injection locked LW-VCSEL simultaneously operating as direct modulated laser and resonant cavity enhanced photodetector, and the results of its experimental investigation to characterize the static and dynamic features in free-running or optical injection-locked modes, and small-signal gain vs RF frequency characteristics for downlink and uplink channels.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"11 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120842057","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768382
I. Gueye, I. Diop, I. Dioum
This article analyzes the impact of the use of error correcting codes, in particular globally coupled LDPC codes (GC-LDPC) in a double-hop relay system composed a multiuser mixed radio frequency (RF) and hybrid RF/FSO (free-space optical). For this configuration, communication between mobile users and a destination is via a buffer assisted decoding and retransmission relay node. Users transmit their data to the relay node over RF links using a virtual multiple input multiple output (MIMO) system. The relay node after decoding the data of all users using two-phase local-global decoding, this data will be transmitted to the destination via an FSO link supported by an RF MIMO backup system to the destination. A multi-antenna listener listens to information by decoding data received from users. The relay temporally stores user data in its buffer memory until the best channel conditions on the relay-destination link are met. For this communication setup, we first suggest using GC-LDPC codes for data encoding and decoding. The numerical results validate that buffering in the physical layer and the use of GC-LDPC codes significantly improve system performance. It is also found that the use of the relay buffer memory, the back-up RF link (in the second hop) and the use of GC-LDPC codes help protect user data against atmospheric turbulence.
{"title":"Performance analysis of multi-user mixed RF and hybrid RF/FSO cooperative systems with buffers based on GC-LDPC codes","authors":"I. Gueye, I. Diop, I. Dioum","doi":"10.1109/scc53769.2021.9768382","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768382","url":null,"abstract":"This article analyzes the impact of the use of error correcting codes, in particular globally coupled LDPC codes (GC-LDPC) in a double-hop relay system composed a multiuser mixed radio frequency (RF) and hybrid RF/FSO (free-space optical). For this configuration, communication between mobile users and a destination is via a buffer assisted decoding and retransmission relay node. Users transmit their data to the relay node over RF links using a virtual multiple input multiple output (MIMO) system. The relay node after decoding the data of all users using two-phase local-global decoding, this data will be transmitted to the destination via an FSO link supported by an RF MIMO backup system to the destination. A multi-antenna listener listens to information by decoding data received from users. The relay temporally stores user data in its buffer memory until the best channel conditions on the relay-destination link are met. For this communication setup, we first suggest using GC-LDPC codes for data encoding and decoding. The numerical results validate that buffering in the physical layer and the use of GC-LDPC codes significantly improve system performance. It is also found that the use of the relay buffer memory, the back-up RF link (in the second hop) and the use of GC-LDPC codes help protect user data against atmospheric turbulence.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129917975","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768381
Farhat Yassin, Atig Asma, Z. Ali, Ben Abdennour Ridha
This paper presents an emulation scheme based on a novel method to adjust the learning rate for multivariable nonlinear dynamical systems. The aim of this paper is to adapt the learning rate of the Neural Emulator (NE) in order to accelerate the convergence speed and to improve the precision degree. To ensure fast convergence and good estimation, an online adaptation is developed using a criterion generated by the error of emulation. The obtained results prouve the efficiency of the designed NE compared to those obtained with an existing one using a fuzzy supervision.
{"title":"A Learning Rate For MIMO Nonlinear System Emulation","authors":"Farhat Yassin, Atig Asma, Z. Ali, Ben Abdennour Ridha","doi":"10.1109/scc53769.2021.9768381","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768381","url":null,"abstract":"This paper presents an emulation scheme based on a novel method to adjust the learning rate for multivariable nonlinear dynamical systems. The aim of this paper is to adapt the learning rate of the Neural Emulator (NE) in order to accelerate the convergence speed and to improve the precision degree. To ensure fast convergence and good estimation, an online adaptation is developed using a criterion generated by the error of emulation. The obtained results prouve the efficiency of the designed NE compared to those obtained with an existing one using a fuzzy supervision.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129980173","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 : 2021-12-20DOI: 10.1109/scc53769.2021.9768380
Tanazefti Asma, Haddouk Amira, M. Hfaiedh
This paper presents the modeling and control of the indoor climate of greenhouses. Indeed, in order to predict the internal climatic parameters of an agricultural greenhouse such as air temperature and relative humidity, it is necessary to model the greenhouse using Matlab / Simulink software. This model describes the transfer of heat and water vapor inside the greenhouse as a function of weather conditions (wind speed, outside temperature, solar radiation, outside humidity, location and structure of the greenhouse, season, etc. etc). Consequently, the all-or-nothing (TOR) regulation has been adapted to the greenhouse model in order to regulate the temperature and humidity of the soil to a precise setpoint. When the plant's water and ventilation needs reach a well-defined threshold, usually chosen by the farmer, the TOR regulator sends the control signals to the solenoid valve to start the irrigation and also to the fan to cool the indoor climate of the greenhouse.
{"title":"Modeling and regulation of the internal climate of an agricultural greenhouse","authors":"Tanazefti Asma, Haddouk Amira, M. Hfaiedh","doi":"10.1109/scc53769.2021.9768380","DOIUrl":"https://doi.org/10.1109/scc53769.2021.9768380","url":null,"abstract":"This paper presents the modeling and control of the indoor climate of greenhouses. Indeed, in order to predict the internal climatic parameters of an agricultural greenhouse such as air temperature and relative humidity, it is necessary to model the greenhouse using Matlab / Simulink software. This model describes the transfer of heat and water vapor inside the greenhouse as a function of weather conditions (wind speed, outside temperature, solar radiation, outside humidity, location and structure of the greenhouse, season, etc. etc). Consequently, the all-or-nothing (TOR) regulation has been adapted to the greenhouse model in order to regulate the temperature and humidity of the soil to a precise setpoint. When the plant's water and ventilation needs reach a well-defined threshold, usually chosen by the farmer, the TOR regulator sends the control signals to the solenoid valve to start the irrigation and also to the fan to cool the indoor climate of the greenhouse.","PeriodicalId":365845,"journal":{"name":"2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115093824","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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