Pub Date : 2019-06-01DOI: 10.1109/YAC.2019.8787621
Tiaoyang Cai, Ran-Ran Zhang
The stabilization of Second Order Time Delay Process (SOTDP) with proportional derivative (PD) controllers is considered. A novel procedure following the line of the $tau$ decomposition method is proposed to characterize the space of controller parameters. The division of the space of controller parameters are related to the determination of the purely imaginary roots (PIRs), and the calculation of stable intervals refers to the order of the PIRs. According to our result, analytical formulas on both topics are obtained and the stability switch (under some certain PD controller) versus delay is revealed. Finally, numerical simulations show the effectiveness and correctness.
{"title":"On the $mathcal{T}$ Decomposition Method for PD Controllers of the Low Order Time Delay Process","authors":"Tiaoyang Cai, Ran-Ran Zhang","doi":"10.1109/YAC.2019.8787621","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787621","url":null,"abstract":"The stabilization of Second Order Time Delay Process (SOTDP) with proportional derivative (PD) controllers is considered. A novel procedure following the line of the $tau$ decomposition method is proposed to characterize the space of controller parameters. The division of the space of controller parameters are related to the determination of the purely imaginary roots (PIRs), and the calculation of stable intervals refers to the order of the PIRs. According to our result, analytical formulas on both topics are obtained and the stability switch (under some certain PD controller) versus delay is revealed. Finally, numerical simulations show the effectiveness and correctness.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"20 1","pages":"166-169"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86056327","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787599
Ke Liu, Zhijun Li
To solve the positioning problem of intelligent following luggage, the positioning method of installing UWB (Ultra-wide-band) on the following luggage has been put forward for its capability of making self-adaptation to Kalman filtering. When luggage is moving, the noise from UWB system will change in accordance with vibration and surrounding environment. Therefore, the range error of distance measurement can be increased and the inhibitory effect of traditional Kalman filtering on error always cannot meet requirements. Concerning the issues above, a weighted self-adaptation Kalman filtering algorithm is proposed. On the basis of synchronized clock and construction of dynamic ranging model, the distance of filtering is set and the triangular centroid coordinates are used to calculate the position on average, improving the reliability and accuracy of positioning. UWB system consists of base stations and tag made of DW1000 radio frequency chips. The base stations are placed at top four corners of the luggage and tag is moved by hand. The experimental results show that, this method can help improve the positioning accuracy of tag effectively, and its path is closer to the real path.
{"title":"Adaptive Kalman Filtering for UWB Positioning in Following Luggage","authors":"Ke Liu, Zhijun Li","doi":"10.1109/YAC.2019.8787599","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787599","url":null,"abstract":"To solve the positioning problem of intelligent following luggage, the positioning method of installing UWB (Ultra-wide-band) on the following luggage has been put forward for its capability of making self-adaptation to Kalman filtering. When luggage is moving, the noise from UWB system will change in accordance with vibration and surrounding environment. Therefore, the range error of distance measurement can be increased and the inhibitory effect of traditional Kalman filtering on error always cannot meet requirements. Concerning the issues above, a weighted self-adaptation Kalman filtering algorithm is proposed. On the basis of synchronized clock and construction of dynamic ranging model, the distance of filtering is set and the triangular centroid coordinates are used to calculate the position on average, improving the reliability and accuracy of positioning. UWB system consists of base stations and tag made of DW1000 radio frequency chips. The base stations are placed at top four corners of the luggage and tag is moved by hand. The experimental results show that, this method can help improve the positioning accuracy of tag effectively, and its path is closer to the real path.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"386 1","pages":"574-578"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85493554","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787665
Wenxiang Zhu, Weiting Zhen, J. Jiao
In the process monitoring of nonlinear systems, kernel function is the main means to solve the nonlinear data by mapping low-dimensional nonlinear data to high-dimensional linear data. However, the use of kernel function has two disadvantages: 1. Kernel function needs a lot of calculation, especially under the condition of large number of training samples, 2. Kernel function leads to the inability to obtain the relationship between input variables and statistics. So that the identification of fault variables is difficult. In this paper, Taylor series expansion is used to remove the high order infinitesimal term, so that the Gaussian kernel function is replaced by the input matrix, which greatly reduces the amount of computation required for fault detection and diagnosis. The replacement method is introduced into the KPLS model, and the input matrix is successfully decomposed into quality-related and unrelated parts by using SVD decomposition. Based on the detection model, through the gradient theory, the partial derivate is used to calculate the gradient of each variable in the statistics to isolate the fault variables. In order to verify the effectiveness of the algorithm, this paper uses the TEP model to carry on the simulation experiment, has obtained the very good process monitoring effect, at the same time has greatly reduced the simulation experiment time.
{"title":"Partial Derivate Contribution Plot Based on KPLS-KSER for Nonlinear Process Fault Diagnosis","authors":"Wenxiang Zhu, Weiting Zhen, J. Jiao","doi":"10.1109/YAC.2019.8787665","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787665","url":null,"abstract":"In the process monitoring of nonlinear systems, kernel function is the main means to solve the nonlinear data by mapping low-dimensional nonlinear data to high-dimensional linear data. However, the use of kernel function has two disadvantages: 1. Kernel function needs a lot of calculation, especially under the condition of large number of training samples, 2. Kernel function leads to the inability to obtain the relationship between input variables and statistics. So that the identification of fault variables is difficult. In this paper, Taylor series expansion is used to remove the high order infinitesimal term, so that the Gaussian kernel function is replaced by the input matrix, which greatly reduces the amount of computation required for fault detection and diagnosis. The replacement method is introduced into the KPLS model, and the input matrix is successfully decomposed into quality-related and unrelated parts by using SVD decomposition. Based on the detection model, through the gradient theory, the partial derivate is used to calculate the gradient of each variable in the statistics to isolate the fault variables. In order to verify the effectiveness of the algorithm, this paper uses the TEP model to carry on the simulation experiment, has obtained the very good process monitoring effect, at the same time has greatly reduced the simulation experiment time.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"29 1","pages":"735-740"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87686744","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787644
Yuanyuan Xu, Caixia Lv
An offshore ship suffers from unmatched disturbance caused by sea waves and currents, which may cause ship overturn accidents and need to be studied. In the paper, the Wigley ship model is taken as the research object and a mechanism model of the ship motion is established. CFD(Computational Fluid Dynamics) method and DGT (Dynamic Grid Technology) are used to analyze the course of a ship motion with high-order stoke wave which can replace sine wave as the input wave. The results show that high-order stoke wave is asymmetrically distributed and the ship motion can be studied by using CFD method and DGT based on high-order stoke wave. The simulation provides a foundation on ship motion in six-degree-of-freedom waves and on the ship's resistance study.
{"title":"Simulations and Analysis on the Course of a Ship Motion Based on CFD and DGT with High-order Stoke Wave","authors":"Yuanyuan Xu, Caixia Lv","doi":"10.1109/YAC.2019.8787644","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787644","url":null,"abstract":"An offshore ship suffers from unmatched disturbance caused by sea waves and currents, which may cause ship overturn accidents and need to be studied. In the paper, the Wigley ship model is taken as the research object and a mechanism model of the ship motion is established. CFD(Computational Fluid Dynamics) method and DGT (Dynamic Grid Technology) are used to analyze the course of a ship motion with high-order stoke wave which can replace sine wave as the input wave. The results show that high-order stoke wave is asymmetrically distributed and the ship motion can be studied by using CFD method and DGT based on high-order stoke wave. The simulation provides a foundation on ship motion in six-degree-of-freedom waves and on the ship's resistance study.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"61 4 1","pages":"184-188"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83938956","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787722
Jiahui Chen, Ze Zhou, Wenjie Chen, Zhaoshuai Sun, Liyan Zhang
Electric vehicles (EV) are the future direction of automotive development, and dynamic wireless charging (DWC) system can effectively solve the difficulty of charging and improve the deficiency in mileage. Therefore, the technology of DWC is an ideal choice for charging electric vehicles. This paper presents the design and analysis of DWC system, and analyses the selection of DC/DC converter and controlled variables. In this study, model predictive control (MPC) is proposed to control DWC system accurately, and MPC is compared with dual loop PID control. Simulation results demonstrate the correctness and effectiveness of the proposed MPC controller in dynamic wireless charging system.
{"title":"Research on Predictive Control of DC/DC Converter for Dynamic Wireless Charging System","authors":"Jiahui Chen, Ze Zhou, Wenjie Chen, Zhaoshuai Sun, Liyan Zhang","doi":"10.1109/YAC.2019.8787722","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787722","url":null,"abstract":"Electric vehicles (EV) are the future direction of automotive development, and dynamic wireless charging (DWC) system can effectively solve the difficulty of charging and improve the deficiency in mileage. Therefore, the technology of DWC is an ideal choice for charging electric vehicles. This paper presents the design and analysis of DWC system, and analyses the selection of DC/DC converter and controlled variables. In this study, model predictive control (MPC) is proposed to control DWC system accurately, and MPC is compared with dual loop PID control. Simulation results demonstrate the correctness and effectiveness of the proposed MPC controller in dynamic wireless charging system.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"24 1","pages":"195-199"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88645474","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787646
Jiaqi Luo, Ying Shi, Lingyun Xie
In this paper, simplification method for ship model is proposed. Firstly, sensitivity index with a depressive strategy is introduced to characterize the significance of hydrodynamic coefficients for higher accuracy. Secondly, an unsupervised learning based simplification is proposed and can properly and effectively reduce the hydrodynamic coefficients. Thirdly, open-loop and closed-loop simulation are carried out to verify that simplification. Experiment result shows that clustering are effective in horizontal rotational movement and horizontal zigzag maneuver with the maximum and minimum errors of the motion parameters are 4.75% and 0.24% respectively within acceptable range.
{"title":"An unsupervised learning based simplification on ship motion model and its verification","authors":"Jiaqi Luo, Ying Shi, Lingyun Xie","doi":"10.1109/YAC.2019.8787646","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787646","url":null,"abstract":"In this paper, simplification method for ship model is proposed. Firstly, sensitivity index with a depressive strategy is introduced to characterize the significance of hydrodynamic coefficients for higher accuracy. Secondly, an unsupervised learning based simplification is proposed and can properly and effectively reduce the hydrodynamic coefficients. Thirdly, open-loop and closed-loop simulation are carried out to verify that simplification. Experiment result shows that clustering are effective in horizontal rotational movement and horizontal zigzag maneuver with the maximum and minimum errors of the motion parameters are 4.75% and 0.24% respectively within acceptable range.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"192 1","pages":"52-57"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77762223","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}
In this paper, 2017's hurricane relief in Puerto Rico as the background, a k-means clustering model based on constrained multi-objective multi-sourced weber problem is introduced to determine the optimal locations of emergency material centers, which minimizes distance between road points and emergency supplies centers and weighted distance between hospitals and emergency supplies centers. To effectively solve the model aforementioned, a novel imperialist competitive algorithm (ICA) is proposed which compares two solutions with the lexicographical method. Finally, the results of real data are given and show the effectiveness in solving the problem.
{"title":"Emergency Supplies Center Location Clustering Model Based on Imperialist Competitive Algorithm","authors":"Haoran Wang, Zexuan Sun, Chengyang Liao, Wanru Cui, Qingyong Zhang","doi":"10.1109/YAC.2019.8787692","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787692","url":null,"abstract":"In this paper, 2017's hurricane relief in Puerto Rico as the background, a k-means clustering model based on constrained multi-objective multi-sourced weber problem is introduced to determine the optimal locations of emergency material centers, which minimizes distance between road points and emergency supplies centers and weighted distance between hospitals and emergency supplies centers. To effectively solve the model aforementioned, a novel imperialist competitive algorithm (ICA) is proposed which compares two solutions with the lexicographical method. Finally, the results of real data are given and show the effectiveness in solving the problem.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"430 1","pages":"375-380"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76493482","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787696
Haibin Shi, Z. Xu, Tao Sun, Chuanping Wu
The internal model principle is used to study the tracking control problem of the rotary double inverted pendulum system. According to the dynamic characteristics of the given signal, the servo compensator and the augmented system are constructed. Then, the tracking control problem is transformed into the optimal control problem, and the feedback control law is calculated by the optimal control theory. A reduced-order state observer is established to estimate the state of the controlled signal by the known state vectors. And it reduces the use of detection devices in the system. The simulation results of the rotary double inverted pendulum system show that the upper pendulum angle can follow the given signal variable change without steady error. Meanwhile, the system has good dynamic performance.
{"title":"Double Inverted Pendulum System Control Based on Internal Model Principle","authors":"Haibin Shi, Z. Xu, Tao Sun, Chuanping Wu","doi":"10.1109/YAC.2019.8787696","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787696","url":null,"abstract":"The internal model principle is used to study the tracking control problem of the rotary double inverted pendulum system. According to the dynamic characteristics of the given signal, the servo compensator and the augmented system are constructed. Then, the tracking control problem is transformed into the optimal control problem, and the feedback control law is calculated by the optimal control theory. A reduced-order state observer is established to estimate the state of the controlled signal by the known state vectors. And it reduces the use of detection devices in the system. The simulation results of the rotary double inverted pendulum system show that the upper pendulum angle can follow the given signal variable change without steady error. Meanwhile, the system has good dynamic performance.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"26 1","pages":"666-670"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75704144","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787649
Kangyu Gao, Qingyong Zhang, Luyang Yu, Lutong Huo
We proposed a new type of light-weight convolutional neural network MRINet for low computing power requirements. This model is applied with strategies including depthwise separable convolution, Channel pruning and ELU activation. It greatly reduces the amount of calculation while getting high accuracy. MRINet can complete the training process and application on mobile phones and other mobile platforms. By integrating into the corresponding application, which can solve many real problems including self-medication. By training on the ISIC dataset, as compared to MobileNet, we improved training speed by 23%, while accuracy is increased 3.3%.
{"title":"A Muti-branch Convolutional Netural Network for Mobile Platform","authors":"Kangyu Gao, Qingyong Zhang, Luyang Yu, Lutong Huo","doi":"10.1109/YAC.2019.8787649","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787649","url":null,"abstract":"We proposed a new type of light-weight convolutional neural network MRINet for low computing power requirements. This model is applied with strategies including depthwise separable convolution, Channel pruning and ELU activation. It greatly reduces the amount of calculation while getting high accuracy. MRINet can complete the training process and application on mobile phones and other mobile platforms. By integrating into the corresponding application, which can solve many real problems including self-medication. By training on the ISIC dataset, as compared to MobileNet, we improved training speed by 23%, while accuracy is increased 3.3%.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"542 1","pages":"357-360"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77919960","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 : 2019-06-01DOI: 10.1109/YAC.2019.8787704
Shiyuan Jia, Shenpei Zhou, Zhiyong Li
The elderly have poor rehabilitation ability, and are prone to complications after falling, which seriously endangers the physical condition of the elderly. Therefore, it is very important to study the balance ability of the elderly and its influencing factors. We constructed a mathematical model to analyze the data related to the walking of the elderly and proposed suggestions for improving stability. Considering the three aspects of gait, center of gravity and motion, 25 eigenvalues were extracted to evaluate the body balance of the elderly. Then, we constructed a balanced risk assessment system for the elderly. The entropy method is used to calculate the information content of eigenvalues as the basis of weighting. We added the elderly BMI and disease history to the risk assessment system for simulation calculation. Borrowing economic thoughts, constructing a random frontier model based on whether the elderly fall as a dependent variable, comparatively analyzing by gender, and studying the influence of gait and exercise on the balance ability of the elderly. We found that gait and center of gravity have a greater impact on the balance of the elderly, BMI has less influence, and the balance between male and female is quite different. Finally, the model is tested. We analyze the sensitivity of each index of the risk assessment system. The results are in line with expectations and the model has certain applicability.
{"title":"Principal component analysis to guide the reduce the risk of fall","authors":"Shiyuan Jia, Shenpei Zhou, Zhiyong Li","doi":"10.1109/YAC.2019.8787704","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787704","url":null,"abstract":"The elderly have poor rehabilitation ability, and are prone to complications after falling, which seriously endangers the physical condition of the elderly. Therefore, it is very important to study the balance ability of the elderly and its influencing factors. We constructed a mathematical model to analyze the data related to the walking of the elderly and proposed suggestions for improving stability. Considering the three aspects of gait, center of gravity and motion, 25 eigenvalues were extracted to evaluate the body balance of the elderly. Then, we constructed a balanced risk assessment system for the elderly. The entropy method is used to calculate the information content of eigenvalues as the basis of weighting. We added the elderly BMI and disease history to the risk assessment system for simulation calculation. Borrowing economic thoughts, constructing a random frontier model based on whether the elderly fall as a dependent variable, comparatively analyzing by gender, and studying the influence of gait and exercise on the balance ability of the elderly. We found that gait and center of gravity have a greater impact on the balance of the elderly, BMI has less influence, and the balance between male and female is quite different. Finally, the model is tested. We analyze the sensitivity of each index of the risk assessment system. The results are in line with expectations and the model has certain applicability.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"5 1","pages":"342-347"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73619848","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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