Pub Date : 2013-05-06DOI: 10.1109/I2MTC.2013.6555724
Yuhua Cheng, Xingmake Liu, Yiming Deng
The laser-based magneto-optic microscopy (LMOM) system is based on eddy current technology and its image quality mainly depends on the incentive effects, where the excitation coil is widely adopted as an incentive device by placing it above the inspecting surface of the specimen. This paper proposed an innovative excitation coil design, which can generate a region of linear eddy current distribution in the specimen and consequently make the uniformly induced magnetic field possible and parallel to the surface in defect-free geometry. The sensitivity of defect imaging will be greatly enhanced since the detected normal magnetic field is only determined by the discontinuities and decoupled with the induced main field. A single rectangular coil and the cross placed coils are studied in this paper and simulation results of the new design were compared with the traditional coil design results, which clearly validated its advantages and demonstrated the potential of the new set up of LMOM to achieve better image resolution and contrast.
{"title":"An innovative exciting coil design for magneto-optic imaging in nondestructive evaluation","authors":"Yuhua Cheng, Xingmake Liu, Yiming Deng","doi":"10.1109/I2MTC.2013.6555724","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555724","url":null,"abstract":"The laser-based magneto-optic microscopy (LMOM) system is based on eddy current technology and its image quality mainly depends on the incentive effects, where the excitation coil is widely adopted as an incentive device by placing it above the inspecting surface of the specimen. This paper proposed an innovative excitation coil design, which can generate a region of linear eddy current distribution in the specimen and consequently make the uniformly induced magnetic field possible and parallel to the surface in defect-free geometry. The sensitivity of defect imaging will be greatly enhanced since the detected normal magnetic field is only determined by the discontinuities and decoupled with the induced main field. A single rectangular coil and the cross placed coils are studied in this paper and simulation results of the new design were compared with the traditional coil design results, which clearly validated its advantages and demonstrated the potential of the new set up of LMOM to achieve better image resolution and contrast.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123572750","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555542
Wilton Lacerda Silva, Amauri Oliveira
This paper investigates some techniques of digital signal processing, using the rotor slot harmonics present in the stator currents waveforms, to estimate the motor slip and the rotational speed when operating in stationary or in nonstationary mode. This research also highlights the importance of identifying whether a motor is capable or not of producing rotor slots harmonics, and shows how it is possible to do this using simple tables. An algorithm to estimate the slip and speed variation was developed. Finally, it has been done some analysis about issues such as: sample rate, window length and the use of the chirp z-Transform with the short time Fourier transform to improve the tests results. It has also been analysed the use of this methodology when the motor is operating powered by a frequency converter and variable load. Furthermore, the efficiency of the method has been confirmed by experimental results.
{"title":"Analysis of spectral signatures of stator currents on a three-phase induction motor operating in non stationary mode for rotational speed and slip detection using rotor slot harmonics","authors":"Wilton Lacerda Silva, Amauri Oliveira","doi":"10.1109/I2MTC.2013.6555542","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555542","url":null,"abstract":"This paper investigates some techniques of digital signal processing, using the rotor slot harmonics present in the stator currents waveforms, to estimate the motor slip and the rotational speed when operating in stationary or in nonstationary mode. This research also highlights the importance of identifying whether a motor is capable or not of producing rotor slots harmonics, and shows how it is possible to do this using simple tables. An algorithm to estimate the slip and speed variation was developed. Finally, it has been done some analysis about issues such as: sample rate, window length and the use of the chirp z-Transform with the short time Fourier transform to improve the tests results. It has also been analysed the use of this methodology when the motor is operating powered by a frequency converter and variable load. Furthermore, the efficiency of the method has been confirmed by experimental results.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123699443","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555380
M. Sakthivel, B. George, J. Venkatraman, M. Sivaprakasam
In this paper, an inductive proximity sensor with a longer range when compared to its diameter is presented. This sensor is intended to guide doctors, while performing surgery to remove metal shrapnel from victims of bomb blasts, gun fire, land mines etc. Presently doctors rely on imaging systems to locate shrapnel in the victim's body before surgery. Effectiveness of surgery and recovery solely depends on the doctors' skill to trace the shrapnel. In some cases the shrapnel may be visible in the images, but it may be untraceable during surgery. So in such cases, an inductive proximity sensor which is small enough to be introduced into the victim's body and can direct the recovery tool effectively to the exact location of the shrapnel, during the surgery, will be very useful to the doctor. Such a sensor, along with its details and experimental results are presented in this paper. This sensor works on a new comparison based method to detect tiny targets, as the detector size is a constraint here. The sensor can detect shrapnel materials such as steel, brass and Aluminium. A smaller, modified version of this sensor is also presented in the paper, along with a study of the effect of body tissues on sensor performance.
{"title":"A new inductive proximity sensor as a guiding tool for removing metal shrapnel during surgery","authors":"M. Sakthivel, B. George, J. Venkatraman, M. Sivaprakasam","doi":"10.1109/I2MTC.2013.6555380","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555380","url":null,"abstract":"In this paper, an inductive proximity sensor with a longer range when compared to its diameter is presented. This sensor is intended to guide doctors, while performing surgery to remove metal shrapnel from victims of bomb blasts, gun fire, land mines etc. Presently doctors rely on imaging systems to locate shrapnel in the victim's body before surgery. Effectiveness of surgery and recovery solely depends on the doctors' skill to trace the shrapnel. In some cases the shrapnel may be visible in the images, but it may be untraceable during surgery. So in such cases, an inductive proximity sensor which is small enough to be introduced into the victim's body and can direct the recovery tool effectively to the exact location of the shrapnel, during the surgery, will be very useful to the doctor. Such a sensor, along with its details and experimental results are presented in this paper. This sensor works on a new comparison based method to detect tiny targets, as the detector size is a constraint here. The sensor can detect shrapnel materials such as steel, brass and Aluminium. A smaller, modified version of this sensor is also presented in the paper, along with a study of the effect of body tissues on sensor performance.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"128 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122501845","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555398
K. Draxler, R. Styblíková
This paper presents the calibration of an electronic voltage divider and precise instrument voltage transformers in the range up to 1 kV at 50 Hz frequency using inductive voltage dividers. We also describe a way to evaluate the difference between a standard inductive divider and a calibrated instrument voltage transformer or electronic voltage divider expressed as the ratio error and phase displacement. The paper also presents the construction of a standard decadic voltage divider with a range of input voltage (10×100) V and (10×10) V.
{"title":"Use of an inductive divider for AC voltage ratio calibration","authors":"K. Draxler, R. Styblíková","doi":"10.1109/I2MTC.2013.6555398","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555398","url":null,"abstract":"This paper presents the calibration of an electronic voltage divider and precise instrument voltage transformers in the range up to 1 kV at 50 Hz frequency using inductive voltage dividers. We also describe a way to evaluate the difference between a standard inductive divider and a calibrated instrument voltage transformer or electronic voltage divider expressed as the ratio error and phase displacement. The paper also presents the construction of a standard decadic voltage divider with a range of input voltage (10×100) V and (10×10) V.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122687164","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555441
A. V. Mulders, L. Vanbeylen
When identifying a system (e.g. mechanical, electrical or chemical) based on inand output measurements and without physical knowledge, an engineer faces many choices. First of all, there exist standard linear models, but when those do not sufficiently well describe the data, nonlinear models should be considered. There are many kinds of nonlinear models and it is often hard to choose among them. Most likely, the engineer will prefer a simple model (containing as few parameters as possible), which is yet flexible enough to describe the data. This paper presents an identification method that results in a block-structured model. The block-structure consists of a linear dynamic part and two (single-input single-output) static nonlinearities. Because of this structure, the model complexity remains reasonable, whereas the structure is flexible enough to describe any system with two static nonlinearities (including Hammerstein-Wiener, Wiener-Hammerstein, nonlinear feedback etc.).
{"title":"Identification of nonlinear LFR systems with two nonlinearities","authors":"A. V. Mulders, L. Vanbeylen","doi":"10.1109/I2MTC.2013.6555441","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555441","url":null,"abstract":"When identifying a system (e.g. mechanical, electrical or chemical) based on inand output measurements and without physical knowledge, an engineer faces many choices. First of all, there exist standard linear models, but when those do not sufficiently well describe the data, nonlinear models should be considered. There are many kinds of nonlinear models and it is often hard to choose among them. Most likely, the engineer will prefer a simple model (containing as few parameters as possible), which is yet flexible enough to describe the data. This paper presents an identification method that results in a block-structured model. The block-structure consists of a linear dynamic part and two (single-input single-output) static nonlinearities. Because of this structure, the model complexity remains reasonable, whereas the structure is flexible enough to describe any system with two static nonlinearities (including Hammerstein-Wiener, Wiener-Hammerstein, nonlinear feedback etc.).","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114262139","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555679
N. Karimian, W. Yin, J. Liu, X. Hao, M. Strangwood, C. Davis, A. Peyton
Analysis of the electromagnetic properties of power station steels, measured using a non-contact EM sensor, is of significance as such properties are indicative of the microstructure of the material. In this paper, we present the measurement of cylindrical power station steel samples (namely P91 and P9 grades) in different conditions. Initially the B-H curves of these steel samples were measured. Then printed circuit board (PCB) coil integrated sensors were used to measure the incremental permeability. Analytical and numerical methods (Finite Elements Methods) were employed to calculate the sensor response of these samples. Experimental results were obtained for a range of samples and their electromagnetic properties inferred by fitting finite element models to the measured results.
{"title":"Non-contact EM measurement of the properties of power station steels taken from service","authors":"N. Karimian, W. Yin, J. Liu, X. Hao, M. Strangwood, C. Davis, A. Peyton","doi":"10.1109/I2MTC.2013.6555679","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555679","url":null,"abstract":"Analysis of the electromagnetic properties of power station steels, measured using a non-contact EM sensor, is of significance as such properties are indicative of the microstructure of the material. In this paper, we present the measurement of cylindrical power station steel samples (namely P91 and P9 grades) in different conditions. Initially the B-H curves of these steel samples were measured. Then printed circuit board (PCB) coil integrated sensors were used to measure the incremental permeability. Analytical and numerical methods (Finite Elements Methods) were employed to calculate the sensor response of these samples. Experimental results were obtained for a range of samples and their electromagnetic properties inferred by fitting finite element models to the measured results.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114366818","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555565
A. Vallan, A. Carullo, M. L. Casalicchio, G. Perrone
Sensors able to measure curvature changes are emerging as an effective alternative to the more common strain gauges in structural health monitoring. Particularly interesting is the optical fiber implementation of such sensors and this paper discusses the design and characterization of a simple, cheap, and compact curvature sensor based on plastic optical fibers. A characterization setup is also proposed in order to test the sensor performances with dynamic deformations.
{"title":"Design and characterization of curvature sensors based on plastic optical fibers for structural monitoring","authors":"A. Vallan, A. Carullo, M. L. Casalicchio, G. Perrone","doi":"10.1109/I2MTC.2013.6555565","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555565","url":null,"abstract":"Sensors able to measure curvature changes are emerging as an effective alternative to the more common strain gauges in structural health monitoring. Particularly interesting is the optical fiber implementation of such sensors and this paper discusses the design and characterization of a simple, cheap, and compact curvature sensor based on plastic optical fibers. A characterization setup is also proposed in order to test the sensor performances with dynamic deformations.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121893350","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555520
R. Procházka, K. Draxler, J. Hlavacek, R. Styblíková
This paper describes the structure and calibration of a resistive divider for DC voltage measurement in the range up to 10 kV or 20 kV. The divider consists of twenty 9.99 MΩ high-voltage resistors and one 100 kΩ output resistor. Circular electrodes create parallel capacitor to appropriate resistors. These thin-film resistors have a tolerance of resistance 0.1 %. The structure is designed to minimize the influence of corona currents and leakage resistance between resistors. This paper describes resistor calibration process of, including verification of their voltage dependence. The divider ratio constant and its uncertainty are calculated on the basis of this calibration. The advantage of the proposed procedure is in easy divider recalibration process. A simple recalibration process is necessary due to the long term usage. The proposed DC voltage divider can be used to measure AC respective impulse voltages as well. The frequency independency in given frequency range is then required. The application of compensatory capacity and automatic correction method ensure the correct compensation of voltage divider.
{"title":"Precise 10 and 20 kV DC/AC resistive divider","authors":"R. Procházka, K. Draxler, J. Hlavacek, R. Styblíková","doi":"10.1109/I2MTC.2013.6555520","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555520","url":null,"abstract":"This paper describes the structure and calibration of a resistive divider for DC voltage measurement in the range up to 10 kV or 20 kV. The divider consists of twenty 9.99 MΩ high-voltage resistors and one 100 kΩ output resistor. Circular electrodes create parallel capacitor to appropriate resistors. These thin-film resistors have a tolerance of resistance 0.1 %. The structure is designed to minimize the influence of corona currents and leakage resistance between resistors. This paper describes resistor calibration process of, including verification of their voltage dependence. The divider ratio constant and its uncertainty are calculated on the basis of this calibration. The advantage of the proposed procedure is in easy divider recalibration process. A simple recalibration process is necessary due to the long term usage. The proposed DC voltage divider can be used to measure AC respective impulse voltages as well. The frequency independency in given frequency range is then required. The application of compensatory capacity and automatic correction method ensure the correct compensation of voltage divider.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122113227","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555406
R. Azambuja, V. Brusamarello, S. Haffner, R. W. Porto
A novel full four capacitor compensation method for inductive power transfer is introduced. To compute the capacitors values, a very simple search algorithm based on Monte Carlo is used. In addiction, some heuristic are used to reduce the size of the search space. The efficiency, output power and power efficiency are compared with some classical approach such as the two capacitors compensation and also with the basic circuit without compensation. The results showed a significant improvement on the efficiency and output power.
{"title":"Full four capacitor circuit compensation for inductive power transfer","authors":"R. Azambuja, V. Brusamarello, S. Haffner, R. W. Porto","doi":"10.1109/I2MTC.2013.6555406","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555406","url":null,"abstract":"A novel full four capacitor compensation method for inductive power transfer is introduced. To compute the capacitors values, a very simple search algorithm based on Monte Carlo is used. In addiction, some heuristic are used to reduce the size of the search space. The efficiency, output power and power efficiency are compared with some classical approach such as the two capacitors compensation and also with the basic circuit without compensation. The results showed a significant improvement on the efficiency and output power.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129518797","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 : 2013-05-06DOI: 10.1109/I2MTC.2013.6555623
H. Eren, H. M. Pakka, A. Alghamdi, Yizuo Yue
This paper describes a ZigBee based wireless system to assists traffic flow on arterial urban roads. Real-time simulation in laboratory environment is conducted to determine the traffic throughput to avoid possible congestions or ease existing congestions. Random numbers are generated to mimic approaching traffic, and this information is shared by a ZigBeebased real-time wirelessly network. Wireless nodes are connected to different PLCs representing different traffic lights in a cluster. Once the information is shared the timing and sequencing decisions are taken collectively in a synchronized manner. In this paper, the information is displayed on SCADA connected to each PLC for viewing the characteristics of continuous vehicular flow. It is found that the topology of the network can play an important role in the throughput of data, which may be critical in safety critical operations such as the control of traffic lights. This paper aims to highlight some of the possible effects of dataflow flow and time-delays faced by modern intelligent control of traffic lights.
{"title":"Instrumentation for safe vehicular flow in intelligent traffic control systems using wireless networks","authors":"H. Eren, H. M. Pakka, A. Alghamdi, Yizuo Yue","doi":"10.1109/I2MTC.2013.6555623","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555623","url":null,"abstract":"This paper describes a ZigBee based wireless system to assists traffic flow on arterial urban roads. Real-time simulation in laboratory environment is conducted to determine the traffic throughput to avoid possible congestions or ease existing congestions. Random numbers are generated to mimic approaching traffic, and this information is shared by a ZigBeebased real-time wirelessly network. Wireless nodes are connected to different PLCs representing different traffic lights in a cluster. Once the information is shared the timing and sequencing decisions are taken collectively in a synchronized manner. In this paper, the information is displayed on SCADA connected to each PLC for viewing the characteristics of continuous vehicular flow. It is found that the topology of the network can play an important role in the throughput of data, which may be critical in safety critical operations such as the control of traffic lights. This paper aims to highlight some of the possible effects of dataflow flow and time-delays faced by modern intelligent control of traffic lights.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129813907","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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