Pub Date : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513361
Luo Jing, L. Cheng, Cao Jian, Cui Miao Feng, W. Yu, Ran Li Jun
At present, the stable production capacity evaluation of gas reservoirs is mostly numerical simulation, and the heterogeneity and water production of gas reservoirs are considered comprehensively. Taking QXZ gas reservoir producing well in Block SYS as an example, this paper optimized the reserves calculation method suitable for each producing well, and obtained the controlled dynamic reserves of each producing well. Based on this, the stable production ability evaluation was carried out, and the material balance method was modified to obtain the stable production ability evaluation method suitable for heterogeneous water producing gas reservoir.
{"title":"Study on production stability of heterogeneous water and gas well:Take QXZ gas reservoir in Block SYS as an example","authors":"Luo Jing, L. Cheng, Cao Jian, Cui Miao Feng, W. Yu, Ran Li Jun","doi":"10.1109/ICMSP53480.2021.9513361","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513361","url":null,"abstract":"At present, the stable production capacity evaluation of gas reservoirs is mostly numerical simulation, and the heterogeneity and water production of gas reservoirs are considered comprehensively. Taking QXZ gas reservoir producing well in Block SYS as an example, this paper optimized the reserves calculation method suitable for each producing well, and obtained the controlled dynamic reserves of each producing well. Based on this, the stable production ability evaluation was carried out, and the material balance method was modified to obtain the stable production ability evaluation method suitable for heterogeneous water producing gas reservoir.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130480801","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513424
Dai Chenyu
To address the defects in the performance of conventional mechanical gas flow meters, this study designed an ultrasonic gas flow measurement circuit by the time-difference method and by relying on the superior performance of the domestic high-precision digital-time converter chip MS1030, and gave detailed introduction to such modules as the time measurement module, the driver amplifier module, the channel switch module, the receiver signal conditioning module, the wave shaping module of the circuit and the implementation software. The performance of the circuit was verified by tests on the standard gas flow measurement device of the critical flow nozzle, and the test results showed that the designed ultrasonic gas flow measurement circuit achieved high accuracy, high reliability and reached the 2.0 level of accuracy in the industry standard.
{"title":"Design of an Ultrasonic Gas Flow Measurement Circuit Based on the Time-Difference Method","authors":"Dai Chenyu","doi":"10.1109/ICMSP53480.2021.9513424","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513424","url":null,"abstract":"To address the defects in the performance of conventional mechanical gas flow meters, this study designed an ultrasonic gas flow measurement circuit by the time-difference method and by relying on the superior performance of the domestic high-precision digital-time converter chip MS1030, and gave detailed introduction to such modules as the time measurement module, the driver amplifier module, the channel switch module, the receiver signal conditioning module, the wave shaping module of the circuit and the implementation software. The performance of the circuit was verified by tests on the standard gas flow measurement device of the critical flow nozzle, and the test results showed that the designed ultrasonic gas flow measurement circuit achieved high accuracy, high reliability and reached the 2.0 level of accuracy in the industry standard.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117027345","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513417
Peng Yangsheng, Chen Yanqiao
It is difficult to identify the monitoring parameters of the cooling pipeline system with seawater as medium when the pipeline is partially blocked and small leakage occurs. The control of condenser vacuum leads to the action of the control valve, which will make the system produce output response. Through theoretical analysis, the output response of the pipeline in different working conditions is different, which makes fault diagnosis possible. Therefore, this paper uses Flowmaster software to establish the models of normal working conditions, partial blocking working conditions and small leakage working conditions. The pressure variation in front of the condenser is simulated, and it is found that the pressure variation under the three working conditions is quite different, which indicates that the fault diagnosis can be carried out by identifying the pressure waveform. 400 groups of experimental data are obtained through simulation. Then the fault diagnosis system established by two different input methods of BP neural network is compared, and it is found that the iterations of taking the time series as the network input are less, the accuracy is as high as 96%.
{"title":"Fault diagnosis of cooling pipeline system","authors":"Peng Yangsheng, Chen Yanqiao","doi":"10.1109/ICMSP53480.2021.9513417","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513417","url":null,"abstract":"It is difficult to identify the monitoring parameters of the cooling pipeline system with seawater as medium when the pipeline is partially blocked and small leakage occurs. The control of condenser vacuum leads to the action of the control valve, which will make the system produce output response. Through theoretical analysis, the output response of the pipeline in different working conditions is different, which makes fault diagnosis possible. Therefore, this paper uses Flowmaster software to establish the models of normal working conditions, partial blocking working conditions and small leakage working conditions. The pressure variation in front of the condenser is simulated, and it is found that the pressure variation under the three working conditions is quite different, which indicates that the fault diagnosis can be carried out by identifying the pressure waveform. 400 groups of experimental data are obtained through simulation. Then the fault diagnosis system established by two different input methods of BP neural network is compared, and it is found that the iterations of taking the time series as the network input are less, the accuracy is as high as 96%.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121475610","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513375
Xuexiu Li, Dayu Zheng, Wenting Nie
Belt drive is an important mechanical drive form, and the tension is an important factor to ensure the normal operation of belt drive. There is a lack of research on the combination of basic theory and experiment in measuring tension with natural frequency of free vibration, this paper studies through two experiments. The first experiment reflects the relationship between tension of experimental machine and other factors, and the second experiment introduces a correction coefficient by processing the measured first-order free vibration frequency, which improves the accuracy of the calculation formula of frequency method. The research results show that the method of calculating tension based on frequency is feasible, and the theoretical relationship and correction coefficient provide theoretical basis for designing tension measuring device based on frequency method.
{"title":"Theoretical and Experimental Research on Measuring Tension by Frequency Method Based on a Testing Machine","authors":"Xuexiu Li, Dayu Zheng, Wenting Nie","doi":"10.1109/ICMSP53480.2021.9513375","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513375","url":null,"abstract":"Belt drive is an important mechanical drive form, and the tension is an important factor to ensure the normal operation of belt drive. There is a lack of research on the combination of basic theory and experiment in measuring tension with natural frequency of free vibration, this paper studies through two experiments. The first experiment reflects the relationship between tension of experimental machine and other factors, and the second experiment introduces a correction coefficient by processing the measured first-order free vibration frequency, which improves the accuracy of the calculation formula of frequency method. The research results show that the method of calculating tension based on frequency is feasible, and the theoretical relationship and correction coefficient provide theoretical basis for designing tension measuring device based on frequency method.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122443685","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513392
Hongbo Liu, Jianwei Gu, Yaxuan Wang, Zhiyong Wei
With the increasing production of heavy oil reservoirs, it is very important to predict the periodic oil production of horizontal well steam stimulation. In view of the difficulties and limitations of conventional forecasting methods, a PCA-GBDT production forecasting method was established based on Principal Component Analysis (PCA) and Gradient Boosting Decision Tree (GBDT). Firstly, On the basis of the existing geological data and field production data, partial data are fused and processed. And then based on grey correlation analysis to all kinds of factors affecting the relevance, we can obtain the main controlling factors of cycle oil production. Next, principal component analysis is used to eliminate the correlation of influencing factors, and a sample library for machine learning is established. Finally, Gradient Boosting Decision Tree was used to train the established machine learning sample library, and grid search was used to optimize the maximum tree depth of model parameters and the number of decision trees to form the yield prediction model. The results show that the PCA-GBDT production prediction model can accurately predict cycle oil production, and the average absolute error is less than 10%, which meets the requirements of field and engineering. This method is of great practical significance for the production and development adjustment of heavy oil horizontal well steam huff and puff and the application of machine learning in unconventional resources.
{"title":"Prediction Method of Heavy Oil Horizontal Well Cycle Oil Production Based on PCA and Gradient Boosting Decision Tree","authors":"Hongbo Liu, Jianwei Gu, Yaxuan Wang, Zhiyong Wei","doi":"10.1109/ICMSP53480.2021.9513392","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513392","url":null,"abstract":"With the increasing production of heavy oil reservoirs, it is very important to predict the periodic oil production of horizontal well steam stimulation. In view of the difficulties and limitations of conventional forecasting methods, a PCA-GBDT production forecasting method was established based on Principal Component Analysis (PCA) and Gradient Boosting Decision Tree (GBDT). Firstly, On the basis of the existing geological data and field production data, partial data are fused and processed. And then based on grey correlation analysis to all kinds of factors affecting the relevance, we can obtain the main controlling factors of cycle oil production. Next, principal component analysis is used to eliminate the correlation of influencing factors, and a sample library for machine learning is established. Finally, Gradient Boosting Decision Tree was used to train the established machine learning sample library, and grid search was used to optimize the maximum tree depth of model parameters and the number of decision trees to form the yield prediction model. The results show that the PCA-GBDT production prediction model can accurately predict cycle oil production, and the average absolute error is less than 10%, which meets the requirements of field and engineering. This method is of great practical significance for the production and development adjustment of heavy oil horizontal well steam huff and puff and the application of machine learning in unconventional resources.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"31 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115307272","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513344
Cong Liu, Xuejie Feng, Lenian Xu, Chenglong Guo
Aiming at the poor adaptive and limited application range of traditional PID control in constant current water supply system, a constant current water supply system based on intelligent control was designed. The electromagnetic flowmeter collected the real-time flow data, and the signal converter was designed to upload the real-time flow data to the upper computer. The real-time error and error change rate were obtained by comparing with the expected value of the flow. PLC controller realized the fuzzy PID control and adjusted the frequency converter in real time to get the steady flow rate more quickly. The simulation experiment is carried out by using Simulink in Matlab. The time of traditional PID control and fuzzy PID control to reach the steady flow is 17s and 11s respectively, and the fuzzy PID has a smaller overshoot. Compared with the traditional PID control, the fuzzy PID control has obvious advantages in adjustment time and overshoot, and the control effect is better and the practical value is greater.
{"title":"Constant Current Water Supply System Design Based on Fuzzy PID Control","authors":"Cong Liu, Xuejie Feng, Lenian Xu, Chenglong Guo","doi":"10.1109/ICMSP53480.2021.9513344","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513344","url":null,"abstract":"Aiming at the poor adaptive and limited application range of traditional PID control in constant current water supply system, a constant current water supply system based on intelligent control was designed. The electromagnetic flowmeter collected the real-time flow data, and the signal converter was designed to upload the real-time flow data to the upper computer. The real-time error and error change rate were obtained by comparing with the expected value of the flow. PLC controller realized the fuzzy PID control and adjusted the frequency converter in real time to get the steady flow rate more quickly. The simulation experiment is carried out by using Simulink in Matlab. The time of traditional PID control and fuzzy PID control to reach the steady flow is 17s and 11s respectively, and the fuzzy PID has a smaller overshoot. Compared with the traditional PID control, the fuzzy PID control has obvious advantages in adjustment time and overshoot, and the control effect is better and the practical value is greater.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130748088","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513328
Lin Li, Y. Bai
Now, the demand for natural gas in all walks of life is increasing. Our country has built a large number of natural gas pipelines. The centrifugal compressor is of great significance to the smooth operation of the natural gas pipeline network. Surge is a dangerous working condition that may occur when the compressor is running, although traditional anti-surge solutions guaranteed basic operational safety, the control effect still has a large amount of rooms for improvement. This paper designs an anti-surge controller based on fuzzy theory and validates it by simulation.
{"title":"Research on Fuzzy Control of Centrifugal Compressor Anti-surge in Long-distance Natural Gas Pipeline","authors":"Lin Li, Y. Bai","doi":"10.1109/ICMSP53480.2021.9513328","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513328","url":null,"abstract":"Now, the demand for natural gas in all walks of life is increasing. Our country has built a large number of natural gas pipelines. The centrifugal compressor is of great significance to the smooth operation of the natural gas pipeline network. Surge is a dangerous working condition that may occur when the compressor is running, although traditional anti-surge solutions guaranteed basic operational safety, the control effect still has a large amount of rooms for improvement. This paper designs an anti-surge controller based on fuzzy theory and validates it by simulation.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130798379","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513363
Dazhang Yang, Yang Li, Qing Zhang, Jing Xie, Jinfeng Wang
The seawater heat exchanger is widely used in coastal energy plants, desalination and ships. In this paper, the application fields of seawater heat exchanger are summarized. This paper introduces the latest research progress of seawater heat exchanger in different fields, and analyzes the advantages and disadvantages of seawater heat exchanger. In addition, the novel material of seawater heat exchanger is introduced in this paper.
{"title":"Application and research progress of seawater heat exchanger","authors":"Dazhang Yang, Yang Li, Qing Zhang, Jing Xie, Jinfeng Wang","doi":"10.1109/ICMSP53480.2021.9513363","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513363","url":null,"abstract":"The seawater heat exchanger is widely used in coastal energy plants, desalination and ships. In this paper, the application fields of seawater heat exchanger are summarized. This paper introduces the latest research progress of seawater heat exchanger in different fields, and analyzes the advantages and disadvantages of seawater heat exchanger. In addition, the novel material of seawater heat exchanger is introduced in this paper.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130690001","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513354
Ze Wang, Dan Wu, Le Hua, Su-li Yan, Zhe Gao, Zhao-xue Wu
At present, the digital meter recognition is widely used in the field of power transmission and transformation, but rarely used in the petrochemical industry. This paper combines traditional image processing techniques with deep learning methods and proposes a meter recognition method based on an improved neural network model. By establishing a neural network model architecture, setting up the three convolutional layers and adding a batch normalization processing operation, the digital meters of the oil extraction platform are recognized, and the recognition rate is about 99.17%, which achieve the expectations. Through comparative research, the model constructed in this paper has a higher recognition accuracy and reflects a better recognition effect.
{"title":"The study of instrument recognition based on convolutional neural network","authors":"Ze Wang, Dan Wu, Le Hua, Su-li Yan, Zhe Gao, Zhao-xue Wu","doi":"10.1109/ICMSP53480.2021.9513354","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513354","url":null,"abstract":"At present, the digital meter recognition is widely used in the field of power transmission and transformation, but rarely used in the petrochemical industry. This paper combines traditional image processing techniques with deep learning methods and proposes a meter recognition method based on an improved neural network model. By establishing a neural network model architecture, setting up the three convolutional layers and adding a batch normalization processing operation, the digital meters of the oil extraction platform are recognized, and the recognition rate is about 99.17%, which achieve the expectations. Through comparative research, the model constructed in this paper has a higher recognition accuracy and reflects a better recognition effect.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"6 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120846541","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 : 2021-07-23DOI: 10.1109/ICMSP53480.2021.9513379
Cong Lin
In order to meet the needs of gas pressure monitoring in the boreholes of coal mines, an optical fiber F-P (Fabry Perot) pressure sensor was designed. Based on the principle of multi-beam interference, the sensor can measure gas pressure in any section of the boreholes. Through laboratory calibration, the sensitivity of the sensor was 0.9482 nm/Kpa; the temperature sensitivity was 0.4429 nm / °C; and the basic error was ±1.06% F.S. All of these can meet the monitoring standards of gas pressure in the boreholes of coal mines.
{"title":"Design of Fiber-Optic F-P Pressure Sensor in Boreholes of Coal Mines","authors":"Cong Lin","doi":"10.1109/ICMSP53480.2021.9513379","DOIUrl":"https://doi.org/10.1109/ICMSP53480.2021.9513379","url":null,"abstract":"In order to meet the needs of gas pressure monitoring in the boreholes of coal mines, an optical fiber F-P (Fabry Perot) pressure sensor was designed. Based on the principle of multi-beam interference, the sensor can measure gas pressure in any section of the boreholes. Through laboratory calibration, the sensitivity of the sensor was 0.9482 nm/Kpa; the temperature sensitivity was 0.4429 nm / °C; and the basic error was ±1.06% F.S. All of these can meet the monitoring standards of gas pressure in the boreholes of coal mines.","PeriodicalId":153663,"journal":{"name":"2021 3rd International Conference on Intelligent Control, Measurement and Signal Processing and Intelligent Oil Field (ICMSP)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117259829","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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