Pub Date : 2019-06-01DOI: 10.1109/yac.2019.8787666
{"title":"[Copyright notice]","authors":"","doi":"10.1109/yac.2019.8787666","DOIUrl":"https://doi.org/10.1109/yac.2019.8787666","url":null,"abstract":"","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89156958","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 order to solve the problems of unstable temperature and pressure in the working environment, the data transmission interference and the difficulty of instrument maintenance, which occur in the industrial field application of the swirlmeter. This paper builds a hardware platform with low-power chips STM32, XTR115 and other devices, and uses the software modular programming idea to realize the product design of intelligent swirlmeter with the two-wire 4∼20mA output. At the same time, a novel networked monitoring platform for the swirlmeter was developed. The platform combines technologies such as wireless transport, database MySQL, and custom communication protocols to enable authorized users to remotely monitor field devices. The experiment proves that the system has high precision, stable operation and reasonable design.
{"title":"Design and implementation of swirlmeter and its monitoring platform","authors":"Ling Jiang, Bingbing Shen, Liang Hua, Juping Gu, Jiahao Zhao, Dongdong Wu","doi":"10.1109/YAC.2019.8787710","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787710","url":null,"abstract":"In order to solve the problems of unstable temperature and pressure in the working environment, the data transmission interference and the difficulty of instrument maintenance, which occur in the industrial field application of the swirlmeter. This paper builds a hardware platform with low-power chips STM32, XTR115 and other devices, and uses the software modular programming idea to realize the product design of intelligent swirlmeter with the two-wire 4∼20mA output. At the same time, a novel networked monitoring platform for the swirlmeter was developed. The platform combines technologies such as wireless transport, database MySQL, and custom communication protocols to enable authorized users to remotely monitor field devices. The experiment proves that the system has high precision, stable operation and reasonable design.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"40 1","pages":"415-420"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78691423","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.2019.8787674
Qi Qiao, Kang Nie, Jiuqiang Deng, Wei Ren, Xinglong Chen, Yao Mao
As the tracking target of the optoelectronic tracking system changes, higher requirements are placed on the tracking accuracy of the optoelectronic tracking system. The optoelectronic tracking system will be subjected to various nonlinear disturbances during the actual operation, which affects the tracking accuracy of the system. In the process of designing traditional PID controllers, the nonlinear factors existing in the system are often neglected. The controller designed by this method is difficult to improve the tracking accuracy of the system. Therefore, in order to improve the tracking accuracy of the optoelectronic tracking system, the primary task is to improve the anti-disturbance capability of the system. This paper uses a sliding mode controller, which has the advantages of fast response, insensitivity to parameter changes and disturbances, to suppress the interference of external disturbances on the system. Among them, the sliding model surface adds the integral term of the position error, and the control law adopts the improved exponential approach law, which effectively suppresses the chattering phenomenon of the sliding mode controller and improves the anti-disturbing ability of the optoelectronic tracking system. The simulation results verify the effectiveness and superiority of the sliding mode control strategy designed in this paper.
{"title":"Sliding Mode Control of the Optoelectronic Stabilized Platform Based on the Exponential Approach Law","authors":"Qi Qiao, Kang Nie, Jiuqiang Deng, Wei Ren, Xinglong Chen, Yao Mao","doi":"10.1109/YAC.2019.8787674","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787674","url":null,"abstract":"As the tracking target of the optoelectronic tracking system changes, higher requirements are placed on the tracking accuracy of the optoelectronic tracking system. The optoelectronic tracking system will be subjected to various nonlinear disturbances during the actual operation, which affects the tracking accuracy of the system. In the process of designing traditional PID controllers, the nonlinear factors existing in the system are often neglected. The controller designed by this method is difficult to improve the tracking accuracy of the system. Therefore, in order to improve the tracking accuracy of the optoelectronic tracking system, the primary task is to improve the anti-disturbance capability of the system. This paper uses a sliding mode controller, which has the advantages of fast response, insensitivity to parameter changes and disturbances, to suppress the interference of external disturbances on the system. Among them, the sliding model surface adds the integral term of the position error, and the control law adopts the improved exponential approach law, which effectively suppresses the chattering phenomenon of the sliding mode controller and improves the anti-disturbing ability of the optoelectronic tracking system. The simulation results verify the effectiveness and superiority of the sliding mode control strategy designed in this paper.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"138 1","pages":"407-410"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77609302","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.2019.8787727
Yanyan Li, Zhichun Jia, Qiuyang Han, Xing Xing
With the development of computer network technology and the expanding application fields, the types of attacks on the system are becoming more and more complex. The systems security and attack classification are always two challenges for application service providers and enterprises. In recent years, many researchers have turned more attention to them and established evaluation and classifiers that can detect feature selection of network traffic anomalies. However, most research work does not cross-validate evaluation results, and there is no way to distinguish between different types of attacks. All kinds of facts prove that it is necessary to take appropriate countermeasures and defensive attacks. In this paper, we propose a classification framework and use a popular public data set KDD to establish a two-level similarity classification model. According to the attack similarity, our method can quickly and correctly classify the attacks. The experimental results show that our method is effective.
{"title":"A Two-level Classification Method for Attacks on the Network","authors":"Yanyan Li, Zhichun Jia, Qiuyang Han, Xing Xing","doi":"10.1109/YAC.2019.8787727","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787727","url":null,"abstract":"With the development of computer network technology and the expanding application fields, the types of attacks on the system are becoming more and more complex. The systems security and attack classification are always two challenges for application service providers and enterprises. In recent years, many researchers have turned more attention to them and established evaluation and classifiers that can detect feature selection of network traffic anomalies. However, most research work does not cross-validate evaluation results, and there is no way to distinguish between different types of attacks. All kinds of facts prove that it is necessary to take appropriate countermeasures and defensive attacks. In this paper, we propose a classification framework and use a popular public data set KDD to establish a two-level similarity classification model. According to the attack similarity, our method can quickly and correctly classify the attacks. The experimental results show that our method is effective.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"17 1","pages":"274-279"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89007446","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.2019.8787621
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.2019.8787633
Y. Zhu, Lin Wu
In the multi-traveling-salesman problem, each salesman must traverse a certain number of cities. The set of these cities is viewed as a unit in this paper. Owing to the shortcomings of the unit structure research in the typical multi-traveling-salesman model, this paper proposes an improved model with quadratic partitioning, which can be applied for the optimization of complex topology structure. Among these complex optimization problems, the structure arrangement of thermoelectric modules is taken as an example. In detail, the equilibrium between terminal voltage and internal resistance is evaluated as the local optimization criterion, and the genetic algorithm is used to solve the problem. The result finally proves that the improved model has excellent applicability by obtaining the high energy conversion of thermoelectric modules.
{"title":"Structure Study of Multiple Traveling Salesman Problem using Genetic Algorithm","authors":"Y. Zhu, Lin Wu","doi":"10.1109/YAC.2019.8787633","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787633","url":null,"abstract":"In the multi-traveling-salesman problem, each salesman must traverse a certain number of cities. The set of these cities is viewed as a unit in this paper. Owing to the shortcomings of the unit structure research in the typical multi-traveling-salesman model, this paper proposes an improved model with quadratic partitioning, which can be applied for the optimization of complex topology structure. Among these complex optimization problems, the structure arrangement of thermoelectric modules is taken as an example. In detail, the equilibrium between terminal voltage and internal resistance is evaluated as the local optimization criterion, and the genetic algorithm is used to solve the problem. The result finally proves that the improved model has excellent applicability by obtaining the high energy conversion of thermoelectric modules.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"93 1","pages":"323-328"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81479617","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.2019.8787599
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.2019.8787611
Wang Wei, Lin Shaohan, Li Kang
In this paper, a laboratory aquaponics system, which is developed to teach undergraduate students at Dalian Ocean University, Liaoning, China, some of the issues regarding aquaponics based on PLC and LabVIEW, is discussed. In this aquaponics system, in order to maintain the ecological balance of water body, Siemens S7-1500 PLC is used to realize data acquisition and automatic control of various sensors and execution devices. LabVIEW programming is used to develop a friendly human-machine interface to realize data display, storage, query and analysis. Finally, the real-time data exchange is completed through OPC communication technology, and the monitoring of the aquaponics system is realized. Experience in using this system in undergraduate teaching indicates that it supports learning of PLC and LabVIEW related courses and it also in line with the marine fisheries characteristics of our school.
{"title":"A Laboratory Aquaponics System via PLC and LabVIEW","authors":"Wang Wei, Lin Shaohan, Li Kang","doi":"10.1109/YAC.2019.8787611","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787611","url":null,"abstract":"In this paper, a laboratory aquaponics system, which is developed to teach undergraduate students at Dalian Ocean University, Liaoning, China, some of the issues regarding aquaponics based on PLC and LabVIEW, is discussed. In this aquaponics system, in order to maintain the ecological balance of water body, Siemens S7-1500 PLC is used to realize data acquisition and automatic control of various sensors and execution devices. LabVIEW programming is used to develop a friendly human-machine interface to realize data display, storage, query and analysis. Finally, the real-time data exchange is completed through OPC communication technology, and the monitoring of the aquaponics system is realized. Experience in using this system in undergraduate teaching indicates that it supports learning of PLC and LabVIEW related courses and it also in line with the marine fisheries characteristics of our school.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"25 1","pages":"547-551"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82248870","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.2019.8787706
Jie Qiu, Kun Xu, Wenqian Hu, Ziwu Ren
This paper presents the improved general-weighted least-norm (IGWLN) method to heighten the optimization ability for the control of redundant manipulator. The IGWLN method ameliorates the mapping relationship between the optimization target and virtual joint by modifying the transformation matrix, which guarantees the accuracy of main task while accomplishing the subtask and reduces the computation compared with the original general-weighted least-norm (GWLN) method. A simulation in contrast to the GWLN method on a seven-degree-of-freedom (7 DOF) redundant manipulator demonstrates the advantages of the IGWLN method while following a given trajectory.
{"title":"A Study on the Optimized Solution of Redundant Manipulators Using Improved General-Weighted Least-Norm Method","authors":"Jie Qiu, Kun Xu, Wenqian Hu, Ziwu Ren","doi":"10.1109/YAC.2019.8787706","DOIUrl":"https://doi.org/10.1109/YAC.2019.8787706","url":null,"abstract":"This paper presents the improved general-weighted least-norm (IGWLN) method to heighten the optimization ability for the control of redundant manipulator. The IGWLN method ameliorates the mapping relationship between the optimization target and virtual joint by modifying the transformation matrix, which guarantees the accuracy of main task while accomplishing the subtask and reduces the computation compared with the original general-weighted least-norm (GWLN) method. A simulation in contrast to the GWLN method on a seven-degree-of-freedom (7 DOF) redundant manipulator demonstrates the advantages of the IGWLN method while following a given trajectory.","PeriodicalId":6669,"journal":{"name":"2019 34rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":"10 1","pages":"597-601"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82855272","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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