Pub Date : 2014-09-11DOI: 10.1109/ICIT.2014.6894947
Li-Na Tang, H. Su, G. Tang
This paper deals with the state observer design problem for a networked control linear system. First, based on a functional transformation to the system output, the networked control system with both network transmission delays of controller-to-actuator and sensor-to-controller was transformed into an equivalent system with only delayed control inputs. Then, by using the transformed system, a state observer for the original networked control system is designed. The design algorithm is proposed and the state estimate accuracy of the state observer is analyzed. Theoretical derivation indicates the state observation error can tend to zero at any decay rate specified in advance. Simulation results show the effectiveness of the proposed design approach.
{"title":"Observer design for networked control systems","authors":"Li-Na Tang, H. Su, G. Tang","doi":"10.1109/ICIT.2014.6894947","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894947","url":null,"abstract":"This paper deals with the state observer design problem for a networked control linear system. First, based on a functional transformation to the system output, the networked control system with both network transmission delays of controller-to-actuator and sensor-to-controller was transformed into an equivalent system with only delayed control inputs. Then, by using the transformed system, a state observer for the original networked control system is designed. The design algorithm is proposed and the state estimate accuracy of the state observer is analyzed. Theoretical derivation indicates the state observation error can tend to zero at any decay rate specified in advance. Simulation results show the effectiveness of the proposed design approach.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115164863","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894881
Taekyun Kim, M. Jang, V. Agelidis
In this paper, a 1.2 kW DC-DC boost converter as a solar photovoltaic pre-regulator is designed to form the basis towards a comparative performance evaluation between similar ratings of 1200 V SiC BJT and Si MOSFET. The heatsink temperature and the measured switching waveforms are then compared by increasing the switching frequency up to 300 kHz and the case temperature up to 150 °C via a high temperature testing setup. Much faster turn-on switching time for SiC BJT, compared with Si MOSFET leads to reduced turn-on switching losses, and consequently the heatsink temperature at 300 kHz reaches only at 53 °C without external cooling such as a fan. For switching performance with case temperature variation, SiC BJT switching waveforms are temperature independent up to 150 °C case temperature. On the other hand, for Si MOSFET turn-on switching time gets faster as the case temperature increases.
本文设计了一个1.2 kW DC-DC升压变换器作为太阳能光伏预调节器，为1200 V SiC BJT和Si MOSFET的相似额定值之间的比较性能评估奠定了基础。然后通过将开关频率提高到300 kHz，并通过高温测试装置将外壳温度提高到150°C，来比较散热器温度和测量的开关波形。与Si MOSFET相比，SiC BJT更快的导通开关时间导致导通开关损耗降低，因此在300 kHz时的散热器温度仅达到53°C，而无需外部冷却，如风扇。对于随壳体温度变化的开关性能，SiC BJT开关波形在壳体温度高达150°C时与温度无关。另一方面，硅MOSFET的导通开关时间随着外壳温度的升高而变快。
{"title":"Experimental performance evaluation of SiC BJT and Si MOSFET for 1.2 kW 300 kHz boost converter as a solar PV pre-regulator","authors":"Taekyun Kim, M. Jang, V. Agelidis","doi":"10.1109/ICIT.2014.6894881","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894881","url":null,"abstract":"In this paper, a 1.2 kW DC-DC boost converter as a solar photovoltaic pre-regulator is designed to form the basis towards a comparative performance evaluation between similar ratings of 1200 V SiC BJT and Si MOSFET. The heatsink temperature and the measured switching waveforms are then compared by increasing the switching frequency up to 300 kHz and the case temperature up to 150 °C via a high temperature testing setup. Much faster turn-on switching time for SiC BJT, compared with Si MOSFET leads to reduced turn-on switching losses, and consequently the heatsink temperature at 300 kHz reaches only at 53 °C without external cooling such as a fan. For switching performance with case temperature variation, SiC BJT switching waveforms are temperature independent up to 150 °C case temperature. On the other hand, for Si MOSFET turn-on switching time gets faster as the case temperature increases.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126259243","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6895003
H. Park, J. Jeon
This paper proposes a method to implement an image filtering module by using 3×3 mask on FPGA. The 3×3 mask filter module has an advantage of minimizing a usage of memory and a propagation delay from input to output. Depending on coefficient value of 3×3 mask filter module, we can acquire several image processing effects such as mean filtering, median filtering, and edge enhancement. When we applied Laplacian filter to enhance sharpness of an image by using the 3×3 mask filter module, not only edges components but also noise components of an image were enhanced by Laplacian filter. So we propose an adaptive edge enhancement by using Laplacian filter that is a method to enhance edge components except noise components of an image by analyzing a variance of pixel data in 3×3 mask. We applied the adaptive edge enhancement by using Laplacian filter to an infrared camera and conducted an experiment about its effect. The experimental result proves that the proposed method is effective to implement the edge enhancement of an image with minimum usage of memory in real time.
{"title":"FPGA design and implementation of edge enhancement by using 3×3 mask filter","authors":"H. Park, J. Jeon","doi":"10.1109/ICIT.2014.6895003","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6895003","url":null,"abstract":"This paper proposes a method to implement an image filtering module by using 3×3 mask on FPGA. The 3×3 mask filter module has an advantage of minimizing a usage of memory and a propagation delay from input to output. Depending on coefficient value of 3×3 mask filter module, we can acquire several image processing effects such as mean filtering, median filtering, and edge enhancement. When we applied Laplacian filter to enhance sharpness of an image by using the 3×3 mask filter module, not only edges components but also noise components of an image were enhanced by Laplacian filter. So we propose an adaptive edge enhancement by using Laplacian filter that is a method to enhance edge components except noise components of an image by analyzing a variance of pixel data in 3×3 mask. We applied the adaptive edge enhancement by using Laplacian filter to an infrared camera and conducted an experiment about its effect. The experimental result proves that the proposed method is effective to implement the edge enhancement of an image with minimum usage of memory in real time.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126266769","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894986
Jonghoon Kim, Dmitry Nikitenkov
This paper investigates a new approach based on the fuzzy logic-controlled methodology that is suitable for analyzing and evaluating large format LiMn2O4 cell performance via online state-of-health (SOH) prediction for energy storage system (ESS) applications. The proposed method for online SOH prediction is comprised of two parts. First of all, the values of the cell resistance R and maximum cell capacity Qmax are calculated from four factors such as voltage, current, time, and temperature that were measured during charge-discharge sequence at unknown temperature. Specifically, in order to minimize of SOH jump and drops with temperature variation, temperature compensation for R normalization is efficiently implemented. Then, using two values R and Qmax previously calculated at unknown temperature, present SOH of an arbitrary LiMn2O4 cell can be predicted using the defined fuzzy-logic inference system. The main advantage of this approach is wide parameters tuning possibility for good correspondence of SOH decay with time, and the possibility to perform suitable online SOH estimation. The proposed model used as part of either a Matlab/Simulink model or an integral part of the battery management system (BMS)-micro controller unit (MCU) of STM32F105VC, was verified by the comparison with experimental data of Samsung SDI 60Ah LiMn2O4 cell and a method for SOH prediction by measuring cell capacity during fully charging/ discharging sequence.
{"title":"Fuzzy logic-controlled online state-of-health (SOH) prediction in large format LiMn2O4 cell for energy storage system (ESS) applications","authors":"Jonghoon Kim, Dmitry Nikitenkov","doi":"10.1109/ICIT.2014.6894986","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894986","url":null,"abstract":"This paper investigates a new approach based on the fuzzy logic-controlled methodology that is suitable for analyzing and evaluating large format LiMn2O4 cell performance via online state-of-health (SOH) prediction for energy storage system (ESS) applications. The proposed method for online SOH prediction is comprised of two parts. First of all, the values of the cell resistance R and maximum cell capacity Qmax are calculated from four factors such as voltage, current, time, and temperature that were measured during charge-discharge sequence at unknown temperature. Specifically, in order to minimize of SOH jump and drops with temperature variation, temperature compensation for R normalization is efficiently implemented. Then, using two values R and Qmax previously calculated at unknown temperature, present SOH of an arbitrary LiMn2O4 cell can be predicted using the defined fuzzy-logic inference system. The main advantage of this approach is wide parameters tuning possibility for good correspondence of SOH decay with time, and the possibility to perform suitable online SOH estimation. The proposed model used as part of either a Matlab/Simulink model or an integral part of the battery management system (BMS)-micro controller unit (MCU) of STM32F105VC, was verified by the comparison with experimental data of Samsung SDI 60Ah LiMn2O4 cell and a method for SOH prediction by measuring cell capacity during fully charging/ discharging sequence.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129662648","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894956
In-soo Kim, Heung-Ho Lee, Jeong-Ho Chang
This study's purpose is the development of diesel generator and controller for stable power operation with design in integrated shift type hybrid generator system excitation diesel and wind power generator in single AC system.
{"title":"A study for parallel operation of a synchronous generator","authors":"In-soo Kim, Heung-Ho Lee, Jeong-Ho Chang","doi":"10.1109/ICIT.2014.6894956","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894956","url":null,"abstract":"This study's purpose is the development of diesel generator and controller for stable power operation with design in integrated shift type hybrid generator system excitation diesel and wind power generator in single AC system.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121055924","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894901
H. Kim, J. H. Jung, E. Nho, I. D. Kim, T. Chun, H. Kim
The power loss of a high power voltage disturbance generator is analyzed to design a high efficient generator. The major components of the generator are 3-phase autotransformer, series transformers, and SCR thyristors, which guarantee cost-effective hardware. To maximize the efficiency of the generator the current through these components should be minimized. The only one parameter that can be adjusted to determine the current level is the turn-ratio of the series transformer. Therefore, the power loss analysis is carried out with the variation of the turn ratio.
{"title":"Power loss analysis of 3-phase voltage disturbance generator with variation of series transformer turn-ratio","authors":"H. Kim, J. H. Jung, E. Nho, I. D. Kim, T. Chun, H. Kim","doi":"10.1109/ICIT.2014.6894901","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894901","url":null,"abstract":"The power loss of a high power voltage disturbance generator is analyzed to design a high efficient generator. The major components of the generator are 3-phase autotransformer, series transformers, and SCR thyristors, which guarantee cost-effective hardware. To maximize the efficiency of the generator the current through these components should be minimized. The only one parameter that can be adjusted to determine the current level is the turn-ratio of the series transformer. Therefore, the power loss analysis is carried out with the variation of the turn ratio.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116429351","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894918
A. Bhattacharya, S. Choudhury
Service composition is one of the key issues in web engineering to satisfy users query on the fly. The efficient composition technique demands low execution time. Moreover, the approach should include the fast delivery of an alternative plan in case of failure in run-time. Most of the existing techniques are unable to deliver any result in case of partial matching with the requirement of the user. In this paper, we have proposed a meta-model in terms of a Graph to work on the above said issues. The Graph that contains information required for composition is prepared offline and is used for generating query specific composition plan. The methodology for finding out the specific composition plan, for partial matching also, is illustrated with an example. The solution is expected to behave in an efficient way in terms of providing dynamic service composition techniques.
{"title":"A Graph based meta-model for speed-up service composition on web","authors":"A. Bhattacharya, S. Choudhury","doi":"10.1109/ICIT.2014.6894918","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894918","url":null,"abstract":"Service composition is one of the key issues in web engineering to satisfy users query on the fly. The efficient composition technique demands low execution time. Moreover, the approach should include the fast delivery of an alternative plan in case of failure in run-time. Most of the existing techniques are unable to deliver any result in case of partial matching with the requirement of the user. In this paper, we have proposed a meta-model in terms of a Graph to work on the above said issues. The Graph that contains information required for composition is prepared offline and is used for generating query specific composition plan. The methodology for finding out the specific composition plan, for partial matching also, is illustrated with an example. The solution is expected to behave in an efficient way in terms of providing dynamic service composition techniques.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116420140","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894892
Kyeung-cheol Bae, Seong-chon Choi, Ji-Hwan Kim, C. Won, Yong-Chae Jung
This paper proposes dynamic battery modeling for LiFePO4 battery simulator. LiFePO4 battery of Li-ion type battery has best characteristic in other type of batteries. So this paper describes LiFePO4 battery model for battery simulator. LiFePO4 battery's voltage waveform is non-linear and changed by transient load. So the shepherd model is applied to describe this non-linear waveform and thevenin battery model is applied to present characteristics of behavior corresponding to the changing of transient load. Also, in order to apply battery model to battery simulator, proposed battery model is converted to discrete time model. Parameters of proposed battery model are estimated in experimental. The proposed battery model is compared getting the voltage waveforms of the battery using experiment with simulation's waveforms is verified.
{"title":"LiFePO4 dynamic battery modeling for battery simulator","authors":"Kyeung-cheol Bae, Seong-chon Choi, Ji-Hwan Kim, C. Won, Yong-Chae Jung","doi":"10.1109/ICIT.2014.6894892","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894892","url":null,"abstract":"This paper proposes dynamic battery modeling for LiFePO4 battery simulator. LiFePO4 battery of Li-ion type battery has best characteristic in other type of batteries. So this paper describes LiFePO4 battery model for battery simulator. LiFePO4 battery's voltage waveform is non-linear and changed by transient load. So the shepherd model is applied to describe this non-linear waveform and thevenin battery model is applied to present characteristics of behavior corresponding to the changing of transient load. Also, in order to apply battery model to battery simulator, proposed battery model is converted to discrete time model. Parameters of proposed battery model are estimated in experimental. The proposed battery model is compared getting the voltage waveforms of the battery using experiment with simulation's waveforms is verified.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126635810","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894877
Jeong-Il Kang, Jonghee Han, Sang-Kyoo Han
A high-efficiency boundary conduction mode (BCM) tapped-inductor boost converter for constant output current applications is proposed. Besides the well-known advantages from the BCM operation such as the significantly relieved diode reverse-recovery and switching loss, the proposed converter shows a switching frequency which is insensitive to the output voltage variations. This makes the proposed converter very attractive in small form factor mobile LED driver applications. The circuit is analyzed in detail, and a design guideline is presented. Experimental results from an LED backlight driver prototype for a 14" notebook computer are also presented.
{"title":"High-efficiency boundary conduction mode tapped-inductor boost LED driver","authors":"Jeong-Il Kang, Jonghee Han, Sang-Kyoo Han","doi":"10.1109/ICIT.2014.6894877","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894877","url":null,"abstract":"A high-efficiency boundary conduction mode (BCM) tapped-inductor boost converter for constant output current applications is proposed. Besides the well-known advantages from the BCM operation such as the significantly relieved diode reverse-recovery and switching loss, the proposed converter shows a switching frequency which is insensitive to the output voltage variations. This makes the proposed converter very attractive in small form factor mobile LED driver applications. The circuit is analyzed in detail, and a design guideline is presented. Experimental results from an LED backlight driver prototype for a 14\" notebook computer are also presented.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123807974","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894970
T. Nozaki, T. Mizoguchi, K. Ohnishi
This paper addresses methods to recreate humanlike motions involving direct contact with objects in robots. Motion reproduction systems using motion information extracted by bilateral teleoperation have been developed. However, conventional systems lack adaptability to difference in environmental location. The objective of this research is realization of a system, which can accommodate to the difference in environmental location. The proposed method uses position offset and time-scaling techniques. The offset value and the time-scaling ratio vary according to the difference between the extracted and current force information in real-time. The validity of the proposed method is verified by comparative experiments. The proposed method accomplishes to accurate reproduction of the stored motion. This proposed method shows the usefulness especially in duration of the contact state and amplitude of the force.
{"title":"Motion reproduction using time-scaling for adaptation to difference in environmental location","authors":"T. Nozaki, T. Mizoguchi, K. Ohnishi","doi":"10.1109/ICIT.2014.6894970","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894970","url":null,"abstract":"This paper addresses methods to recreate humanlike motions involving direct contact with objects in robots. Motion reproduction systems using motion information extracted by bilateral teleoperation have been developed. However, conventional systems lack adaptability to difference in environmental location. The objective of this research is realization of a system, which can accommodate to the difference in environmental location. The proposed method uses position offset and time-scaling techniques. The offset value and the time-scaling ratio vary according to the difference between the extracted and current force information in real-time. The validity of the proposed method is verified by comparative experiments. The proposed method accomplishes to accurate reproduction of the stored motion. This proposed method shows the usefulness especially in duration of the contact state and amplitude of the force.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129156616","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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