Pub Date : 2013-04-23DOI: 10.1109/ICIT.2013.6505925
A. Schantin
In this work we propose an iterative decoder scheme for a long-range RFID system. Based on the results of existing works that suggest it is beneficial to employ forward error correction in future RFID systems, we investigate the possibilities for iteratively decoding the baseband code and the channel code of the system. We evaluate the proposed scheme by simulating its bit-error rate performance and analyze the convergence behavior of the iterative decoder, based on its extrinsic information transfer characteristics.
{"title":"Iterative decoding of baseband and channel codes in a long-range RFID system","authors":"A. Schantin","doi":"10.1109/ICIT.2013.6505925","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505925","url":null,"abstract":"In this work we propose an iterative decoder scheme for a long-range RFID system. Based on the results of existing works that suggest it is beneficial to employ forward error correction in future RFID systems, we investigate the possibilities for iteratively decoding the baseband code and the channel code of the system. We evaluate the proposed scheme by simulating its bit-error rate performance and analyze the convergence behavior of the iterative decoder, based on its extrinsic information transfer characteristics.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126619525","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505686
Z. De Grève, M. Delhaye, G. Lossa, F. Vallée
In this paper, the limits and consequences of an algorithm proposed in for the determination of the stator leakage reactance of synchronous machines are highlighted. This method requires the recording of the stator voltage/current characteristic of the machine unloaded and unexcited, in addition with the classical open-circuit characteristic. This approach has been implemented in our applications but instability problems appeared during the unloaded and unexcited test. In order to overcome this limitation, the use of a well-known alternative test (the slip test) in specific conditions is proposed here. We applied it to two types of synchronous machines (salient and non-salient pole synchronous machines) and have reached reliable results. Finally, in order to judge the efficiency of the method proposed in front of measurement errors, a sensitivity analysis was also conducted.
{"title":"Contribution to the determination of the stator leakage reactance of synchronous generators","authors":"Z. De Grève, M. Delhaye, G. Lossa, F. Vallée","doi":"10.1109/ICIT.2013.6505686","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505686","url":null,"abstract":"In this paper, the limits and consequences of an algorithm proposed in for the determination of the stator leakage reactance of synchronous machines are highlighted. This method requires the recording of the stator voltage/current characteristic of the machine unloaded and unexcited, in addition with the classical open-circuit characteristic. This approach has been implemented in our applications but instability problems appeared during the unloaded and unexcited test. In order to overcome this limitation, the use of a well-known alternative test (the slip test) in specific conditions is proposed here. We applied it to two types of synchronous machines (salient and non-salient pole synchronous machines) and have reached reliable results. Finally, in order to judge the efficiency of the method proposed in front of measurement errors, a sensitivity analysis was also conducted.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126130531","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505853
Z. Iqbal, M. Gidlund, J. Åkerberg
Recent years have endorsed momentous development in the industrial wireless sensor and actuator networks (IWSN) for real time communication. For industrial automation application these wireless networks like ZigBee and wireless HART indeed propose advantages in term of cost and flexibility, but the price to be paid is lower reliability in term of unpredictable delay time and lower throughput. In this paper a new mechanism known as wireless arbitration, is proposed for the nodes to access medium in the wireless sensor and actuator network according to their priority. In this new mechanism a specific arbitration frequency is allotted to each node according to the priority of the node in the network, so the node interested to access the medium will transmit its frequency for a fixed amount of time, and all the transmitted frequencies will be received by each node. The received frequencies will then be compared to give the medium access to the high priority node. This mechanism makes the delay deterministic by allocating the medium to the highest priority node in fixed arbitration time, which improves maximum throughput, minimum delay and bandwidth efficiency with allowing event based medium access.
{"title":"Deterministic and event triggered MAC protocol for industrial wireless networks","authors":"Z. Iqbal, M. Gidlund, J. Åkerberg","doi":"10.1109/ICIT.2013.6505853","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505853","url":null,"abstract":"Recent years have endorsed momentous development in the industrial wireless sensor and actuator networks (IWSN) for real time communication. For industrial automation application these wireless networks like ZigBee and wireless HART indeed propose advantages in term of cost and flexibility, but the price to be paid is lower reliability in term of unpredictable delay time and lower throughput. In this paper a new mechanism known as wireless arbitration, is proposed for the nodes to access medium in the wireless sensor and actuator network according to their priority. In this new mechanism a specific arbitration frequency is allotted to each node according to the priority of the node in the network, so the node interested to access the medium will transmit its frequency for a fixed amount of time, and all the transmitted frequencies will be received by each node. The received frequencies will then be compared to give the medium access to the high priority node. This mechanism makes the delay deterministic by allocating the medium to the highest priority node in fixed arbitration time, which improves maximum throughput, minimum delay and bandwidth efficiency with allowing event based medium access.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122015375","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505786
B. Kabasa, E. Rashayi, E. Chikuni
Ligthning phenomenon is a common occurrence in Southern Africa, particularly during the summer and rainy season. Cloud-to-ground lightning is a common natural atmospheric hazard in Zimbabwe. Despite, Zimbabwe being one of the countries with high casualty figures expressed as annual deaths per million, the country currently has no installed Lightning Location and Detection (LLD) System. The Meteorological Services Department of Zimbabwe appears to be relying on word of mouth in compiling statistics on lightning activity and lightning-related casualties in Zimbabwe. This paper presents an online monitoring system that monitors the incidence and severity of lightning and sends the acquired data to an online central server using GSM network in real time. It discusses the design and implementation of an Intelligent Electronic Device (IED) for online monitoring of lightning incidence and severity in rural Zimbabwe using GSM network. The intelligent electronic device captures the signals it receives from a lightning detector before sending the data to a central server using GSM network.Initial laboratory tests were carried out and the device managed to successfully send SMS messages to a central server.
{"title":"Online monitoring of lightning incidence and severity in rural Zimbabwe","authors":"B. Kabasa, E. Rashayi, E. Chikuni","doi":"10.1109/ICIT.2013.6505786","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505786","url":null,"abstract":"Ligthning phenomenon is a common occurrence in Southern Africa, particularly during the summer and rainy season. Cloud-to-ground lightning is a common natural atmospheric hazard in Zimbabwe. Despite, Zimbabwe being one of the countries with high casualty figures expressed as annual deaths per million, the country currently has no installed Lightning Location and Detection (LLD) System. The Meteorological Services Department of Zimbabwe appears to be relying on word of mouth in compiling statistics on lightning activity and lightning-related casualties in Zimbabwe. This paper presents an online monitoring system that monitors the incidence and severity of lightning and sends the acquired data to an online central server using GSM network in real time. It discusses the design and implementation of an Intelligent Electronic Device (IED) for online monitoring of lightning incidence and severity in rural Zimbabwe using GSM network. The intelligent electronic device captures the signals it receives from a lightning detector before sending the data to a central server using GSM network.Initial laboratory tests were carried out and the device managed to successfully send SMS messages to a central server.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126043396","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505755
C. de Beer, P. Barendse, P. Pillay, B. Bullecks, R. Rengaswamy
This paper presents the effect different degradation mechanisms have on the electrical performance of a high temperature PEM fuel cell. The changes to the fuel cell composition and internal chemistry is related the drop in electrical performance. In particular, three main effects will be discussed. This includes the impact of carbon support and catalyst degradation, loss of phosphoric acid in the membrane and CO poisoning of the catalyst layer.
{"title":"Degradation of high temperature PEM fuel cells and the impact on electrical performance","authors":"C. de Beer, P. Barendse, P. Pillay, B. Bullecks, R. Rengaswamy","doi":"10.1109/ICIT.2013.6505755","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505755","url":null,"abstract":"This paper presents the effect different degradation mechanisms have on the electrical performance of a high temperature PEM fuel cell. The changes to the fuel cell composition and internal chemistry is related the drop in electrical performance. In particular, three main effects will be discussed. This includes the impact of carbon support and catalyst degradation, loss of phosphoric acid in the membrane and CO poisoning of the catalyst layer.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126977837","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505749
S. Mostafaei, S. Beheshti, B. Wu, Dongxiang Zhang, H. Wang, H. Xing
This paper presents a novel active anti-islanding detection scheme for the three phase grid-connected converters. The proposed hybrid method works based on the combination of Positive Feedback Frequency Shift (PFFS) and Reactive Power Variation (RPV) methods, and therefore it combines the features of both methods. Unlike the RPV scheme, this method is capable of synchronizing all power converters with each other in a distributed generation (DG) system. Therefore, it can effectively detect islanding when the DG system has multiple renewable energy sources interfaced to the system by multiple converters. The proposed method can also be combined with other active methods, such as the active frequency drift method. This minimizes the power quality degradation since the scheme is called upon only when 0.1Hz deviation in the grid frequency is detected. Moreover, unlike other positive feedback methods, this scheme has little impact on the stability of the DG system, since the positive feedback reference is only limited to ± 0.5% of the converter generated power. The performance of the proposed method is verified by simulation and experiments.
{"title":"A novel hybrid active anti-islanding method for multi-converter fed distributed generation systems","authors":"S. Mostafaei, S. Beheshti, B. Wu, Dongxiang Zhang, H. Wang, H. Xing","doi":"10.1109/ICIT.2013.6505749","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505749","url":null,"abstract":"This paper presents a novel active anti-islanding detection scheme for the three phase grid-connected converters. The proposed hybrid method works based on the combination of Positive Feedback Frequency Shift (PFFS) and Reactive Power Variation (RPV) methods, and therefore it combines the features of both methods. Unlike the RPV scheme, this method is capable of synchronizing all power converters with each other in a distributed generation (DG) system. Therefore, it can effectively detect islanding when the DG system has multiple renewable energy sources interfaced to the system by multiple converters. The proposed method can also be combined with other active methods, such as the active frequency drift method. This minimizes the power quality degradation since the scheme is called upon only when 0.1Hz deviation in the grid frequency is detected. Moreover, unlike other positive feedback methods, this scheme has little impact on the stability of the DG system, since the positive feedback reference is only limited to ± 0.5% of the converter generated power. The performance of the proposed method is verified by simulation and experiments.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127347275","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505839
Vladan Popovic, Hossein Afshari, A. Schmid, Y. Leblebici
Panoptic is a custom spherical light field camera used as a polydioptric system where imagers are distributed over a spherical geometry, each having its own vision of the surrounding and a distinct focal plane. The spherical light field camera records light information from any direction around its center. A novel Gaussian blending technique is presented for vision reconstruction of a virtual observer located inside the spherical geometry of this camera. This blending technique improves the output quality of the reconstructed image with respect to ordinary stitching techniques and simpler image blending algorithms. A hardware architecture based on Field Programmable Gate Arrays (FPGA) with the real-time implementation of the Gaussian blending algorithm using the spherical light field camera is presented, along with the imaging results.
{"title":"Real-time implementation of Gaussian image blending in a spherical light field camera","authors":"Vladan Popovic, Hossein Afshari, A. Schmid, Y. Leblebici","doi":"10.1109/ICIT.2013.6505839","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505839","url":null,"abstract":"Panoptic is a custom spherical light field camera used as a polydioptric system where imagers are distributed over a spherical geometry, each having its own vision of the surrounding and a distinct focal plane. The spherical light field camera records light information from any direction around its center. A novel Gaussian blending technique is presented for vision reconstruction of a virtual observer located inside the spherical geometry of this camera. This blending technique improves the output quality of the reconstructed image with respect to ordinary stitching techniques and simpler image blending algorithms. A hardware architecture based on Field Programmable Gate Arrays (FPGA) with the real-time implementation of the Gaussian blending algorithm using the spherical light field camera is presented, along with the imaging results.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124278029","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505649
G. Fourlas
In this paper we develop and we propose a method to detect faults in a four wheel skid steering mobile robot (SSMR). The basic idea behind the method is to use odometry in order to estimate robot parameters. For this purpose we develop kinematic model of the mobile robot that can be used to estimate odometry parameters. These parameters are the radius of right and left wheels RR and RL respectively. Faults are detected using residuals generated from differences between sensors measurements and estimated values. The advantage of the proposed method is that does not need additional sensors and only position encoders are used. Pioneer 3-AT was used as a robotic platform.
{"title":"Fault detection approach for a 4 - wheel skid steering mobile robot","authors":"G. Fourlas","doi":"10.1109/ICIT.2013.6505649","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505649","url":null,"abstract":"In this paper we develop and we propose a method to detect faults in a four wheel skid steering mobile robot (SSMR). The basic idea behind the method is to use odometry in order to estimate robot parameters. For this purpose we develop kinematic model of the mobile robot that can be used to estimate odometry parameters. These parameters are the radius of right and left wheels RR and RL respectively. Faults are detected using residuals generated from differences between sensors measurements and estimated values. The advantage of the proposed method is that does not need additional sensors and only position encoders are used. Pioneer 3-AT was used as a robotic platform.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"531 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124514096","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505987
Carlo Cecati, C. Buccella, P. Siano, A. Piccolo
The integration of Distributed Generation (DG) based on renewable energy sources in Smart Grids (SGs) is considered a challenging task due to the intermittent nature of the renewable energy sources that are only partly predictable and to the requirement related to the consumers' participation in the electricity market. This paper proposes an Energy Management System (EMS) integrating demand side management and active management schemes for the optimal operation of a SG in presence of DG based on renewable energy sources. Simulation results demonstrate that a better integration of DG can be achieved with the proposed EMS allowing flexibility enhancement and energy costs reduction for customers.
{"title":"Optimal operation of Smart Grids with demand side management","authors":"Carlo Cecati, C. Buccella, P. Siano, A. Piccolo","doi":"10.1109/ICIT.2013.6505987","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505987","url":null,"abstract":"The integration of Distributed Generation (DG) based on renewable energy sources in Smart Grids (SGs) is considered a challenging task due to the intermittent nature of the renewable energy sources that are only partly predictable and to the requirement related to the consumers' participation in the electricity market. This paper proposes an Energy Management System (EMS) integrating demand side management and active management schemes for the optimal operation of a SG in presence of DG based on renewable energy sources. Simulation results demonstrate that a better integration of DG can be achieved with the proposed EMS allowing flexibility enhancement and energy costs reduction for customers.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121700286","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505704
P. Nussbaumer, T. Wolbank, M. Vogelsberger
Industrial application of adjustable speed drives (ASD) has been constantly growing in the last decades. In addition to the sheer number of inverter-fed drives the variety of application fields is increasing too. The use of such ASD in safety critical devices or industrial systems with many drives installed leads to the requirement of increased reliability. Furthermore many drives are operated at or near their rated values to increase efficiency and return on investment. In comparison to mains-fed machines, high dynamics and the fast switching of the inverter adds significant stress to different components of inverter-fed drives. The electrical machine is one of the most important components in these drives. A major cause for machine breakdown is insulation related fault. It is important to mention that such faults do not occur suddenly but origin in an alteration of the insulation condition and finally lead to short circuits. This alteration of the insulation leads to changes in the machine's high-frequency (hf) behavior. To reduce the number of breakdowns and apply predictive maintenance insulation monitoring can be implemented. Monitoring of the machine's hf-behavior can be used to assess the insulation condition by investigation of the transients in the current or voltage. Thus oversampling of the sensor signals is needed. The needed sampling rate and resolution to detect alterations in the machine's hf-behavior is investigated by experimental results.
{"title":"Sensitivity analysis of insulation state indicator in dependence of sampling rate and bit resolution to define hardware requirements","authors":"P. Nussbaumer, T. Wolbank, M. Vogelsberger","doi":"10.1109/ICIT.2013.6505704","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505704","url":null,"abstract":"Industrial application of adjustable speed drives (ASD) has been constantly growing in the last decades. In addition to the sheer number of inverter-fed drives the variety of application fields is increasing too. The use of such ASD in safety critical devices or industrial systems with many drives installed leads to the requirement of increased reliability. Furthermore many drives are operated at or near their rated values to increase efficiency and return on investment. In comparison to mains-fed machines, high dynamics and the fast switching of the inverter adds significant stress to different components of inverter-fed drives. The electrical machine is one of the most important components in these drives. A major cause for machine breakdown is insulation related fault. It is important to mention that such faults do not occur suddenly but origin in an alteration of the insulation condition and finally lead to short circuits. This alteration of the insulation leads to changes in the machine's high-frequency (hf) behavior. To reduce the number of breakdowns and apply predictive maintenance insulation monitoring can be implemented. Monitoring of the machine's hf-behavior can be used to assess the insulation condition by investigation of the transients in the current or voltage. Thus oversampling of the sensor signals is needed. The needed sampling rate and resolution to detect alterations in the machine's hf-behavior is investigated by experimental results.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121808538","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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