Pub Date : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101744
Zou Hai, Zheng Ying, Du Enwu
In this paper, a method for modelling and control of feedwater piping system based on internal characteristics of the feedwater pump is introduced considering the modelling, control and simulation of the feedwater control system. The traditional modelling based on characteristic curves of the feedwater pump can only describe the steady-state characteristics of the feedwater piping system, while the modelling method of feedwater piping system based on the internal characteristics of the feedwater pump can simultaneously simulate both the steady-state and dynamic characteristics of the feedwater piping system, providing a simulation test object for feedwater control system design. A mathematical model of the feedwater piping system based on the internal characteristics of the feedwater pump is created according to the momentum moment theorem and latticed wing analysis theorem. VC++6.0 is applied to develop the simulation program and the Runge-Kutta method is applied for solving the mathematical model. In this paper, we also design the feedwater pump speed control system, apply the scheme of simultaneous control of feedwater regulating valve pressure difference and turbine feedwater pump speed difference, and increase the anti-interference ability of the feedwater pump in parallel operation. The speed control system of the turbine feedwater pump is verified by simulation tests on typical working conditions of the feedwater piping system. Simulation results show that this modelling method can describe the steady-state and dynamic characteristics correctly, with certain significance in engineering application.
{"title":"Research on method for modelling and control of feedwater piping system based on internal characteristics of the feedwater pump","authors":"Zou Hai, Zheng Ying, Du Enwu","doi":"10.1109/ICEMI46757.2019.9101744","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101744","url":null,"abstract":"In this paper, a method for modelling and control of feedwater piping system based on internal characteristics of the feedwater pump is introduced considering the modelling, control and simulation of the feedwater control system. The traditional modelling based on characteristic curves of the feedwater pump can only describe the steady-state characteristics of the feedwater piping system, while the modelling method of feedwater piping system based on the internal characteristics of the feedwater pump can simultaneously simulate both the steady-state and dynamic characteristics of the feedwater piping system, providing a simulation test object for feedwater control system design. A mathematical model of the feedwater piping system based on the internal characteristics of the feedwater pump is created according to the momentum moment theorem and latticed wing analysis theorem. VC++6.0 is applied to develop the simulation program and the Runge-Kutta method is applied for solving the mathematical model. In this paper, we also design the feedwater pump speed control system, apply the scheme of simultaneous control of feedwater regulating valve pressure difference and turbine feedwater pump speed difference, and increase the anti-interference ability of the feedwater pump in parallel operation. The speed control system of the turbine feedwater pump is verified by simulation tests on typical working conditions of the feedwater piping system. Simulation results show that this modelling method can describe the steady-state and dynamic characteristics correctly, with certain significance in engineering application.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115370673","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101497
L. Jianyi
This text introduces a kind of method that testing the voltage of the oscilloscope calibrator square wave signal according to the common instrument including digital voltmeter. It doesn’t need to purchase pulse voltmeter or develop a card and a test-software. It can make use of the resources which laboratory existing. The method can solve the problem that testing the voltage of the square wave signal of the oscilloscope calibrator by the high sample voltmeter like the 3458A.
{"title":"Research on the method of measuring the square wave voltage of oscilloscope calibrator based on digital voltmeter","authors":"L. Jianyi","doi":"10.1109/ICEMI46757.2019.9101497","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101497","url":null,"abstract":"This text introduces a kind of method that testing the voltage of the oscilloscope calibrator square wave signal according to the common instrument including digital voltmeter. It doesn’t need to purchase pulse voltmeter or develop a card and a test-software. It can make use of the resources which laboratory existing. The method can solve the problem that testing the voltage of the square wave signal of the oscilloscope calibrator by the high sample voltmeter like the 3458A.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115473477","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101765
Liao Yanjun, Zhang Jiawei, Tang Wei, Zhang Wei
As an essential component of Logging While Drilling (LWD) tool, controller is responsible for logging flow control, instruction decoding, environmental parameter measurement and data storage. Firmware with high reliability has substantial significance to ensure reliable work of the controller. A design and analysis method of controller’s firmware is proposed in this paper. On the basis of function analysis of the controller, a flexible firmware architecture using modularization technology is presented. On the other hand, an improved Failure Modes Effects and Criticality Analysis (FMECA) method is presented, which considers coupling degree in determining conditional probability to introduce severe results given a failure mode occurs. Engineers can optimize the strategy of design resource distribution after criticality analysis, which may further improve the reliability of the controller’s firmware. The proposed design and analysis method of reliable firmware is applied to new type neutron LWD tool’s controller, which has worked reliably in several offshore wells.
{"title":"Design and analysis method of reliable firmware of LWD tool’s controller","authors":"Liao Yanjun, Zhang Jiawei, Tang Wei, Zhang Wei","doi":"10.1109/ICEMI46757.2019.9101765","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101765","url":null,"abstract":"As an essential component of Logging While Drilling (LWD) tool, controller is responsible for logging flow control, instruction decoding, environmental parameter measurement and data storage. Firmware with high reliability has substantial significance to ensure reliable work of the controller. A design and analysis method of controller’s firmware is proposed in this paper. On the basis of function analysis of the controller, a flexible firmware architecture using modularization technology is presented. On the other hand, an improved Failure Modes Effects and Criticality Analysis (FMECA) method is presented, which considers coupling degree in determining conditional probability to introduce severe results given a failure mode occurs. Engineers can optimize the strategy of design resource distribution after criticality analysis, which may further improve the reliability of the controller’s firmware. The proposed design and analysis method of reliable firmware is applied to new type neutron LWD tool’s controller, which has worked reliably in several offshore wells.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126818160","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101892
Liu Linyun, Wang Lei
For the reasons of lacking rigid foundations and the impact of wind-wave external loads, offshore floating wind turbines with additional motion and load operate at a more severe environment than onshore and bottom-fixed offshore wind turbines. In our work, a multiple tuned mass damper (TMD) control structure and active control method are studied to reduce the load on the barge-type floating wind turbine. These TMDs are considered to be installed both in the nacelle and platform and a state feedback controller is employed. To design an active structural controller, first, a motion constraint model with multiple TMDs is built according to the Euler-Lagrange equation. Then, we applied a linear quadratic (LQR) regulator to actively reduce the load of the turbines. Through the simulation results under different external loads, it comes to conclusion that with multiple active TMDs could reduce the main load of the wind turbines and improve generated power quality.
{"title":"Active structural control of floating wind turbine with Multi-TMD based on LQR optimal control","authors":"Liu Linyun, Wang Lei","doi":"10.1109/ICEMI46757.2019.9101892","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101892","url":null,"abstract":"For the reasons of lacking rigid foundations and the impact of wind-wave external loads, offshore floating wind turbines with additional motion and load operate at a more severe environment than onshore and bottom-fixed offshore wind turbines. In our work, a multiple tuned mass damper (TMD) control structure and active control method are studied to reduce the load on the barge-type floating wind turbine. These TMDs are considered to be installed both in the nacelle and platform and a state feedback controller is employed. To design an active structural controller, first, a motion constraint model with multiple TMDs is built according to the Euler-Lagrange equation. Then, we applied a linear quadratic (LQR) regulator to actively reduce the load of the turbines. Through the simulation results under different external loads, it comes to conclusion that with multiple active TMDs could reduce the main load of the wind turbines and improve generated power quality.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"364 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116054966","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101619
L. Jiyao, Ou Pan, Wang Qi, Zheng Yiwei, Peng Yuming
Standing wave acoustic levitation utilizes the acoustic radiation forces generated by standing wave to hold samples against gravity. Among them, ultrasonic levitation using phased arrays has good application prospects. The principle of standing wave acoustic levitation is analyzed, and the experimental scheme of acoustic levitation using phased arrays is designed to evaluate the performance of ultrasonic levitator. The distribution of sound pressure between two arrays are approximately hourglass-shaped in space, and experimental results show that with the increase of the number of transducers, the suspension ability increases further,. The experiment of liquid droplet suspension further verifies the relationship between the voltage of excitation signal and the acoustic pressure. With the increase of the voltage of the excitation signal, the acoustic pressure amplitude increases gradually. The acoustic levitation using phased arrays is stable and insensitive to temperature, and can effectively improve the levitation ability.
{"title":"Study on suspension ability of concave spherical ultrasound standing wave using phased arrays","authors":"L. Jiyao, Ou Pan, Wang Qi, Zheng Yiwei, Peng Yuming","doi":"10.1109/ICEMI46757.2019.9101619","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101619","url":null,"abstract":"Standing wave acoustic levitation utilizes the acoustic radiation forces generated by standing wave to hold samples against gravity. Among them, ultrasonic levitation using phased arrays has good application prospects. The principle of standing wave acoustic levitation is analyzed, and the experimental scheme of acoustic levitation using phased arrays is designed to evaluate the performance of ultrasonic levitator. The distribution of sound pressure between two arrays are approximately hourglass-shaped in space, and experimental results show that with the increase of the number of transducers, the suspension ability increases further,. The experiment of liquid droplet suspension further verifies the relationship between the voltage of excitation signal and the acoustic pressure. With the increase of the voltage of the excitation signal, the acoustic pressure amplitude increases gradually. The acoustic levitation using phased arrays is stable and insensitive to temperature, and can effectively improve the levitation ability.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114569185","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101435
S. Yue, Xu Aidong, Wang Kai, Han Xiaojia, Guo Haifeng, Zhao Wei
As a critical component in rotating machinery field, rolling bearings are prone to damage under the working conditions of high speed, heavy load and strong impact, resulting in the reduction of production efficiency or even production outage. Therefore, fault diagnosis of rolling bearing plays a significant role in improving the availability of the rotating machinery equipment. The fault recognition rate of the existing fault diagnosis techniques of wavelet packet energy feature is low. Thus, a fault diagnosis approach of bearing is proposed to address this issue in this paper. First, in view of the non-stationary and non-linear properties of the rolling bearing vibration signals, namely, time domain features, frequency domain features, time-frequency domain features and entropy feature are selected to form high-dimensional feature vectors. Second, principal component analysis (PCA) technique with dimension reduction ability is adopted to process high-dimensional features to further remove noise and redundant features and prevent over-fitting. Third, BP neural network is utilized to perform fault diagnosis. Finally, the rolling bearing vibration data of Case Western Reserve University (CWRU) is applied to verify the proposed approach. The diagnosis results shows that the proposed approach has higher fault recognition rate than the traditional wavelet packet energy features based fault diagnosis approach.
{"title":"A novel bearing fault diagnosis method based on principal component analysis and BP neural network","authors":"S. Yue, Xu Aidong, Wang Kai, Han Xiaojia, Guo Haifeng, Zhao Wei","doi":"10.1109/ICEMI46757.2019.9101435","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101435","url":null,"abstract":"As a critical component in rotating machinery field, rolling bearings are prone to damage under the working conditions of high speed, heavy load and strong impact, resulting in the reduction of production efficiency or even production outage. Therefore, fault diagnosis of rolling bearing plays a significant role in improving the availability of the rotating machinery equipment. The fault recognition rate of the existing fault diagnosis techniques of wavelet packet energy feature is low. Thus, a fault diagnosis approach of bearing is proposed to address this issue in this paper. First, in view of the non-stationary and non-linear properties of the rolling bearing vibration signals, namely, time domain features, frequency domain features, time-frequency domain features and entropy feature are selected to form high-dimensional feature vectors. Second, principal component analysis (PCA) technique with dimension reduction ability is adopted to process high-dimensional features to further remove noise and redundant features and prevent over-fitting. Third, BP neural network is utilized to perform fault diagnosis. Finally, the rolling bearing vibration data of Case Western Reserve University (CWRU) is applied to verify the proposed approach. The diagnosis results shows that the proposed approach has higher fault recognition rate than the traditional wavelet packet energy features based fault diagnosis approach.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114576145","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101833
L. Xiang, Liu Xiaoqin, Liu Yaohua
Attitude and heading reference system (AHRS) is indispensible in miniature unmanned aerial vehicles (UAV).Data fusion for magnetometer, accelerometer, and gyroscope in AHRS is usually implemented using extended Kalman filter (EKF) or complementary filter (CF). But due to the curse of dimensionality, sensor error compensation is difficult to be fully included in the design of EKF or CF. In this paper, a novel attitude estimator based on recurrent neural network (RNN) is introduced. This algorithm takes the observations of gravity vector, geomagnetic vector, and angular velocity vector as its inputs, and it can eliminate sensor errors while implementing dynamic attitude estimation. Simulation and experiment results of the proposed algorithm prove its effectiveness.
{"title":"Attitude estimation based on recurrent neural network and vector observations for attitude and heading reference system","authors":"L. Xiang, Liu Xiaoqin, Liu Yaohua","doi":"10.1109/ICEMI46757.2019.9101833","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101833","url":null,"abstract":"Attitude and heading reference system (AHRS) is indispensible in miniature unmanned aerial vehicles (UAV).Data fusion for magnetometer, accelerometer, and gyroscope in AHRS is usually implemented using extended Kalman filter (EKF) or complementary filter (CF). But due to the curse of dimensionality, sensor error compensation is difficult to be fully included in the design of EKF or CF. In this paper, a novel attitude estimator based on recurrent neural network (RNN) is introduced. This algorithm takes the observations of gravity vector, geomagnetic vector, and angular velocity vector as its inputs, and it can eliminate sensor errors while implementing dynamic attitude estimation. Simulation and experiment results of the proposed algorithm prove its effectiveness.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129619183","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101571
Liu Min, Lu Yesheng, Bian Xingyuan, Cheng Zhongyi, Cui Junning
A low ripple switching power supply with 0-12 V voltage and 35 A maximum current outputs is developed for the application of high-precision thermoelectric circulating water cooling. In order to suppress the voltage ripple in the output caused by voltage and current spikes generated when the switching mode of full-bridge converter changes, which is further resulted from parasitic capacitance and inductance of MOSFET circuit and rectifier diode circuit in the power supply, resonance analysis and optimization design is carried out. Equivalent models of MOSFET circuit and rectifier diode circuit are established, and absorption circuits are designed to absorb the voltage and current spikes, thus to effectively suppress the voltage ripple in the output of the switching power supply. Experimental results show that the output voltage ripple is reduced from 190 mV to 88 mV after optimization of key parameter.
{"title":"Low ripple switching power supply for thermoelectric driving based on resonance analysis","authors":"Liu Min, Lu Yesheng, Bian Xingyuan, Cheng Zhongyi, Cui Junning","doi":"10.1109/ICEMI46757.2019.9101571","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101571","url":null,"abstract":"A low ripple switching power supply with 0-12 V voltage and 35 A maximum current outputs is developed for the application of high-precision thermoelectric circulating water cooling. In order to suppress the voltage ripple in the output caused by voltage and current spikes generated when the switching mode of full-bridge converter changes, which is further resulted from parasitic capacitance and inductance of MOSFET circuit and rectifier diode circuit in the power supply, resonance analysis and optimization design is carried out. Equivalent models of MOSFET circuit and rectifier diode circuit are established, and absorption circuits are designed to absorb the voltage and current spikes, thus to effectively suppress the voltage ripple in the output of the switching power supply. Experimental results show that the output voltage ripple is reduced from 190 mV to 88 mV after optimization of key parameter.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128334158","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 : 2019-11-01DOI: 10.1109/ICEMI46757.2019.9101688
Yang Pengcheng, Wang Ning, Cheng Changkuo, Du Junlan
Nitrate sensor based on ultraviolet absorption spectrometry has been developed for measurement of nitrate in seawater. Compared with the chemical laboratory analyses, no chemical regents are required when ultraviolet absorption spectrometry is applied. It is quicker, simpler and easier to perform in on-line measurement. In response to marine environment, the sensor has been designed with an electrical scraper which is used to automatically clean the optical windows before measurement and effectively reduce the influence of biofouling. The results of the comparison experiment for standard solution show that the nitrate sensor has a good performance in accuracy which the average relative error is lower than 10%, and the correlation of the nitrate sensor with laboratory method for seawater samples is higher than 0.9. The nitrate sensor has now been deployed in Bohai sea floor for long-term on-line monitoring, running stably and acquiring large quantities of nitrate data.
{"title":"Nitrate sensor based on ultraviolet absorption spectrometry for seawater: design, comparison and application","authors":"Yang Pengcheng, Wang Ning, Cheng Changkuo, Du Junlan","doi":"10.1109/ICEMI46757.2019.9101688","DOIUrl":"https://doi.org/10.1109/ICEMI46757.2019.9101688","url":null,"abstract":"Nitrate sensor based on ultraviolet absorption spectrometry has been developed for measurement of nitrate in seawater. Compared with the chemical laboratory analyses, no chemical regents are required when ultraviolet absorption spectrometry is applied. It is quicker, simpler and easier to perform in on-line measurement. In response to marine environment, the sensor has been designed with an electrical scraper which is used to automatically clean the optical windows before measurement and effectively reduce the influence of biofouling. The results of the comparison experiment for standard solution show that the nitrate sensor has a good performance in accuracy which the average relative error is lower than 10%, and the correlation of the nitrate sensor with laboratory method for seawater samples is higher than 0.9. The nitrate sensor has now been deployed in Bohai sea floor for long-term on-line monitoring, running stably and acquiring large quantities of nitrate data.","PeriodicalId":419168,"journal":{"name":"2019 14th IEEE International Conference on Electronic Measurement & Instruments (ICEMI)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129446262","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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