Lithium battery internal resistance is an important reference index to evaluate lithium battery performance. Since the mechanism of lithium battery internal resistance is complex and changeable, it cannot be directly measured in a general way. In this paper, an orthogonal vector phase locked amplifier, which uses the AC injection method and adopts the virtual instrument technology, Labview, as the platform, is developed to alleviate noise influence and phase difference of the traditional analog phase locked amplifier. The experiment results show that the system can achieve real-time and on-line measurement of lithium battery internal resistance with considerable accuracy. The experiment results also indicate that the system can accurately measure the internal resistance at the milliohm level with a high level of confidence.
{"title":"System design of lithium battery internal resistance measurement using LabVIEW","authors":"Cun Chang, Tianjian Wu, Wanfu Yang, Hao Li, Zhonghan Hao, Qing Chang","doi":"10.1117/12.2524264","DOIUrl":"https://doi.org/10.1117/12.2524264","url":null,"abstract":"Lithium battery internal resistance is an important reference index to evaluate lithium battery performance. Since the mechanism of lithium battery internal resistance is complex and changeable, it cannot be directly measured in a general way. In this paper, an orthogonal vector phase locked amplifier, which uses the AC injection method and adopts the virtual instrument technology, Labview, as the platform, is developed to alleviate noise influence and phase difference of the traditional analog phase locked amplifier. The experiment results show that the system can achieve real-time and on-line measurement of lithium battery internal resistance with considerable accuracy. The experiment results also indicate that the system can accurately measure the internal resistance at the milliohm level with a high level of confidence.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"60 31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122455522","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}
W. Hao, Su-ping Chang, Jianfei Zhou, Chunbing Hu, Zhongyu Zhang
In this paper, the dynamic and static contact characteristics of the aerostatic bearing stylus displacement sensor are analyzed, including static contact damage and dynamic response. The dynamic response at frequency and different speeds is studied and obtained the relationship between the measured force and frequency and velocity. The stylus does not contact well from the surface when the measuring force is less than 0. In this case, the traceability of the tip can be analyzed based on the characteristics of the amplitude. Finally, the experimental verification of the relevant theory is obtained by measuring the aluminum turning sample at different speeds.
{"title":"Analysis of contacting characteristics on aerostatic bearing stylus displacement sensor","authors":"W. Hao, Su-ping Chang, Jianfei Zhou, Chunbing Hu, Zhongyu Zhang","doi":"10.1117/12.2511216","DOIUrl":"https://doi.org/10.1117/12.2511216","url":null,"abstract":"In this paper, the dynamic and static contact characteristics of the aerostatic bearing stylus displacement sensor are analyzed, including static contact damage and dynamic response. The dynamic response at frequency and different speeds is studied and obtained the relationship between the measured force and frequency and velocity. The stylus does not contact well from the surface when the measuring force is less than 0. In this case, the traceability of the tip can be analyzed based on the characteristics of the amplitude. Finally, the experimental verification of the relevant theory is obtained by measuring the aluminum turning sample at different speeds.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131953696","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}
Qi-yu Wang, Lishuang Mou, Jinyang Feng, Chun-jian Li, D. Su, Shuqing Wu
The 10th International Comparison of Absolute Gravimeters (ICAG-2017) was held in Changping campus of National Institute of Metrology (NIM), China in October 2017. The observation of gravity variations using relative gravimeters plays an important role in absolute gravimeter comparison and the link of gravity reference value after comparison. We carried out a continuous observation of gPhone gravimeter-119 simultaneously alongside a superconductive gravimeter iGrav-012 for several months. The calibration factor of gPhone-119 is determined to be 0.99355±0.00004 with a precision of 0.004%. When the observation time exceeds 33000 minutes, the calibration values and uncertainties tend to be stable and the precision is better than 0.01%. The non-tidal gravity changes during ICAG-2017 recorded by gPhone-119 are analyzed. The tendency of gravity variations is roughly consistent with that recorded by iGrav-012. The result indicates that the peak-to-peak value of gravity changes is less than 1.5 μGal during the period of ICAG-2017.
{"title":"Investigation on gPhone gravimeter-119 for gravity variations observation during the 10th International Comparison of Absolute Gravimeters (ICAG-2017)","authors":"Qi-yu Wang, Lishuang Mou, Jinyang Feng, Chun-jian Li, D. Su, Shuqing Wu","doi":"10.1117/12.2512020","DOIUrl":"https://doi.org/10.1117/12.2512020","url":null,"abstract":"The 10th International Comparison of Absolute Gravimeters (ICAG-2017) was held in Changping campus of National Institute of Metrology (NIM), China in October 2017. The observation of gravity variations using relative gravimeters plays an important role in absolute gravimeter comparison and the link of gravity reference value after comparison. We carried out a continuous observation of gPhone gravimeter-119 simultaneously alongside a superconductive gravimeter iGrav-012 for several months. The calibration factor of gPhone-119 is determined to be 0.99355±0.00004 with a precision of 0.004%. When the observation time exceeds 33000 minutes, the calibration values and uncertainties tend to be stable and the precision is better than 0.01%. The non-tidal gravity changes during ICAG-2017 recorded by gPhone-119 are analyzed. The tendency of gravity variations is roughly consistent with that recorded by iGrav-012. The result indicates that the peak-to-peak value of gravity changes is less than 1.5 μGal during the period of ICAG-2017.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125376412","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}
The analysis of Key Comparison data is to determine the Key Comparison Reference Value (KCRV) and its uncertainty. In the current model, the weighted mean is used as KCRV which is put forward by M, G, Cox. However, the method qualifies the measurement results as Gaussian distribution and does not apply to T distribution or other, which causes the risks of chi-square test failure. When the data analysis is invalid based on conventional statistics, the Bayesian approach may be a valid and welcome alternative. Bayesian inference is often required to solve high-dimensional integrations which Markov chain Monte Carlo (MCMC) is such a method. Here is a simple example used to illustrate the application of this method in metrology. The Metropolis-Hastings algorithm is the most flexible and efficient algorithm in MCMC method. In this paper, its basic concepts are explained and the algorithm steps are given. Besides, we obtain the KCRV and its uncertainty using the Metropolis-Hastings algorithm through MATLAB. Then, the convergence of MCMC is diagnosed. In principle, the MCMC method works for any starting value and any proposal distribution. In practice, however, both choices affect performance. We illustrate this influence with the example.
{"title":"The analysis of key comparison reference value and its uncertainty using Markov chain Monte Carlo method","authors":"Haiyun Zhang, Dinghua Xu, Jianli Liu, Tiepeng Zhao","doi":"10.1117/12.2511633","DOIUrl":"https://doi.org/10.1117/12.2511633","url":null,"abstract":"The analysis of Key Comparison data is to determine the Key Comparison Reference Value (KCRV) and its uncertainty. In the current model, the weighted mean is used as KCRV which is put forward by M, G, Cox. However, the method qualifies the measurement results as Gaussian distribution and does not apply to T distribution or other, which causes the risks of chi-square test failure. When the data analysis is invalid based on conventional statistics, the Bayesian approach may be a valid and welcome alternative. Bayesian inference is often required to solve high-dimensional integrations which Markov chain Monte Carlo (MCMC) is such a method. Here is a simple example used to illustrate the application of this method in metrology. The Metropolis-Hastings algorithm is the most flexible and efficient algorithm in MCMC method. In this paper, its basic concepts are explained and the algorithm steps are given. Besides, we obtain the KCRV and its uncertainty using the Metropolis-Hastings algorithm through MATLAB. Then, the convergence of MCMC is diagnosed. In principle, the MCMC method works for any starting value and any proposal distribution. In practice, however, both choices affect performance. We illustrate this influence with the example.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126665097","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}
With the maturing of liquid crystal technology, liquid crystal variable retarder (LCVR) has been widely used in optical systems. In practice, it is of great importance to characterize the polarization properties of the LCVR for its control and applications to accurately modulate the polarization state of the light in the optical systems. In this paper, the Mueller matrix ellipsometry (MME) is applied to comprehensively characterize the polarization properties including the retardance and the fast axis azimuth of the LCVR versus the driving voltage, the wavelength, as well as the incidence and the azimuth of the light. An analytical model is constructed to describe the LCVR based on the Mueller matrix calculus, in which the influences of the incidence and the azimuth of the light are considered. A house-developed spectroscopic Mueller matrix ellipsometer is employed to perform the experiments. Simulations and experiments about a commercial LCVR product are presented and discussed to verify the proposed method.
{"title":"Characterization of a liquid crystal variable retarder by Mueller matrix ellipsometry","authors":"Peng Wei, Honggang Gu, Xiuguo Chen, Hao Jiang, Chuanwei Zhang, Shiyuan Liu","doi":"10.1117/12.2511431","DOIUrl":"https://doi.org/10.1117/12.2511431","url":null,"abstract":"With the maturing of liquid crystal technology, liquid crystal variable retarder (LCVR) has been widely used in optical systems. In practice, it is of great importance to characterize the polarization properties of the LCVR for its control and applications to accurately modulate the polarization state of the light in the optical systems. In this paper, the Mueller matrix ellipsometry (MME) is applied to comprehensively characterize the polarization properties including the retardance and the fast axis azimuth of the LCVR versus the driving voltage, the wavelength, as well as the incidence and the azimuth of the light. An analytical model is constructed to describe the LCVR based on the Mueller matrix calculus, in which the influences of the incidence and the azimuth of the light are considered. A house-developed spectroscopic Mueller matrix ellipsometer is employed to perform the experiments. Simulations and experiments about a commercial LCVR product are presented and discussed to verify the proposed method.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"IM-36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126644697","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}
Changchun Chai, H. Zhou, Peng Zhou, Chi Zhang, Hongzhou Yan, Xiaojun Liu
In this paper, a structural illumination based technology for microscopic surface topography measurement is investigated, in which only one shot structural illumination image is grabbed and a more efficient optical sectioned image reconstruction algorithm based on Hilbert transform was proposed. Compared with other methods, the technology can avoid strip artefacts problems of in-focus images resulting from the sinusoidal phases mismatch in spatial domain in conventional three-step phase-shifting since the phase-shifting steps decreases from three to one, and the measurement time is decreased effectively. The experimental testing is carried out to verify the feasibility and its measurement accuracy.
{"title":"More efficient optical sectioning structured illumination microscopy","authors":"Changchun Chai, H. Zhou, Peng Zhou, Chi Zhang, Hongzhou Yan, Xiaojun Liu","doi":"10.1117/12.2512099","DOIUrl":"https://doi.org/10.1117/12.2512099","url":null,"abstract":"In this paper, a structural illumination based technology for microscopic surface topography measurement is investigated, in which only one shot structural illumination image is grabbed and a more efficient optical sectioned image reconstruction algorithm based on Hilbert transform was proposed. Compared with other methods, the technology can avoid strip artefacts problems of in-focus images resulting from the sinusoidal phases mismatch in spatial domain in conventional three-step phase-shifting since the phase-shifting steps decreases from three to one, and the measurement time is decreased effectively. The experimental testing is carried out to verify the feasibility and its measurement accuracy.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116903026","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}
The standard near-silicon liquid (2329kg/m3) is a mixture liquid of tribromopropane and dibromoethane in a certain proportion. This liquid is used to measure the density of single crystal silicon spheres by a static suspension method and the analysis of the difference in the micro density between two silicon spheres. Measuring the difference in the micro-density of the silicon spheres is of great significance for the new definition of the new mass of kilograms. In order to obtain the micro-density difference of the silicon spheres, it is necessary to calculate the static pressure value and the temperature by separately adjusting the singlecrystal silicon spheres to the same suspension state and the compression coefficient of the near-monocrystalline silicon density liquid. Through the adjustment of the same hydrostatic suspension state of a single silica ball in different suspension states, the linear constants measured by the linear model are analyzed to calculate the liquid compression coefficient. For this purpose, a static suspension measuring device for a single crystal silicon ball was designed to maintain the water bath within a range of ±0.1mk within 3 hours, and the position control of the silicon ball was determined by controlling the pressure of the upper computer.
{"title":"Measurement method of the compression coefficient of near-monocrystalline silicon density liquid","authors":"Xin-yu Ma, Jin-tao Wang, Zhi-Yong Luo","doi":"10.1117/12.2512095","DOIUrl":"https://doi.org/10.1117/12.2512095","url":null,"abstract":"The standard near-silicon liquid (2329kg/m3) is a mixture liquid of tribromopropane and dibromoethane in a certain proportion. This liquid is used to measure the density of single crystal silicon spheres by a static suspension method and the analysis of the difference in the micro density between two silicon spheres. Measuring the difference in the micro-density of the silicon spheres is of great significance for the new definition of the new mass of kilograms. In order to obtain the micro-density difference of the silicon spheres, it is necessary to calculate the static pressure value and the temperature by separately adjusting the singlecrystal silicon spheres to the same suspension state and the compression coefficient of the near-monocrystalline silicon density liquid. Through the adjustment of the same hydrostatic suspension state of a single silica ball in different suspension states, the linear constants measured by the linear model are analyzed to calculate the liquid compression coefficient. For this purpose, a static suspension measuring device for a single crystal silicon ball was designed to maintain the water bath within a range of ±0.1mk within 3 hours, and the position control of the silicon ball was determined by controlling the pressure of the upper computer.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116030797","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}
Laser tracker has been introduced successfully for geometric deviations calibration of multi-axis machine tools. In this paper, a new method called “pose measurement principle” is developed for measuring geometrical error of rotary axes by means of a single laser tracker and NC precise table. The reflector is mounted on the NC precise table with eccentricity, and the NC precise table is mounted on rotary table. A single laser tracker located at different base stations in order is used for coordinate determination of three fixed points of the reflector to get the pose information of rotary axes, then calculate the pose deviations and identify all the errors. For the error identification, first of all, with the extension of the definition of geometric errors, the 6 geometric errors is represented by pose deviation. Second, 3 angular errors are identified geometrically first, then eliminate the angular errors of all measuring coordinates to obtain the 3 straightness errors. Finally, the 6 errors mathematical model for rotary table is developed. The validity of the proposed method has been confirmed by simulations and experiments. From both of them, it has been confirmed that the proposed method gives precise results and is able to apply to the measurement of rotary axes effectively.
{"title":"Error mapping for rotary axes of machine tools based on pose measurement principle","authors":"Hai-Tao Li, Jiangong Sun, Xianming Gao, Xinlong Yang, Junjie Guo","doi":"10.1117/12.2511850","DOIUrl":"https://doi.org/10.1117/12.2511850","url":null,"abstract":"Laser tracker has been introduced successfully for geometric deviations calibration of multi-axis machine tools. In this paper, a new method called “pose measurement principle” is developed for measuring geometrical error of rotary axes by means of a single laser tracker and NC precise table. The reflector is mounted on the NC precise table with eccentricity, and the NC precise table is mounted on rotary table. A single laser tracker located at different base stations in order is used for coordinate determination of three fixed points of the reflector to get the pose information of rotary axes, then calculate the pose deviations and identify all the errors. For the error identification, first of all, with the extension of the definition of geometric errors, the 6 geometric errors is represented by pose deviation. Second, 3 angular errors are identified geometrically first, then eliminate the angular errors of all measuring coordinates to obtain the 3 straightness errors. Finally, the 6 errors mathematical model for rotary table is developed. The validity of the proposed method has been confirmed by simulations and experiments. From both of them, it has been confirmed that the proposed method gives precise results and is able to apply to the measurement of rotary axes effectively.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117189599","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}
Tong Wang, Tao Liu, Shuming Yang, Biyao Cheng, Qiang Liu, Kang Liu
To realize a long working distance and high resolution focusing for diffraction optical element, the large-scale optical elements need to be employed. Based on the vectorial angular spectrum theory and genetic algorithm, a large-scale metallic multi-annular metasurface (MAM) was designed. The MAM realizes subwavelength focusing and has a main focal spot within the range of 0–140 μm. The focal length is 113.5 μm. Using electron beam lithography, the designed MAM was fabricated. The experimental setup was built. The intensity distribution of the main focal spot was experimentally obtained. The theoretical and experimental results have a good agreement, which show that the proposed method can be used to design the large-scale MAM.
{"title":"Subwavelength focusing and experimental detection of large-scale metallic multi-annular metasurfaces","authors":"Tong Wang, Tao Liu, Shuming Yang, Biyao Cheng, Qiang Liu, Kang Liu","doi":"10.1117/12.2517191","DOIUrl":"https://doi.org/10.1117/12.2517191","url":null,"abstract":"To realize a long working distance and high resolution focusing for diffraction optical element, the large-scale optical elements need to be employed. Based on the vectorial angular spectrum theory and genetic algorithm, a large-scale metallic multi-annular metasurface (MAM) was designed. The MAM realizes subwavelength focusing and has a main focal spot within the range of 0–140 μm. The focal length is 113.5 μm. Using electron beam lithography, the designed MAM was fabricated. The experimental setup was built. The intensity distribution of the main focal spot was experimentally obtained. The theoretical and experimental results have a good agreement, which show that the proposed method can be used to design the large-scale MAM.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123032973","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}
We present a simple method to measure the 3 dB linewidth of the sharp peak in the spectrum of the fiber Bragg gratingbased Fabry–Perot (FBG-FP) interferometer. A narrow linewidth tunable laser is used for sweeping the FBG-FP to achieve the reflection spectrum. A triangle wave is used to drive the narrow linewidth tunable laser. The linewidth of the sharp peak is measured with a resolution of 0.001 pm.
{"title":"Measurement of 3-dB linewidth of FBG Fabry-Perot interferometer using tunable fiber laser","authors":"Dajuan Lyu, Peide Liu, Yifei Ma, Wentao Zhang, Liangming Xiong","doi":"10.1117/12.2509936","DOIUrl":"https://doi.org/10.1117/12.2509936","url":null,"abstract":"We present a simple method to measure the 3 dB linewidth of the sharp peak in the spectrum of the fiber Bragg gratingbased Fabry–Perot (FBG-FP) interferometer. A narrow linewidth tunable laser is used for sweeping the FBG-FP to achieve the reflection spectrum. A triangle wave is used to drive the narrow linewidth tunable laser. The linewidth of the sharp peak is measured with a resolution of 0.001 pm.","PeriodicalId":115119,"journal":{"name":"International Symposium on Precision Engineering Measurement and Instrumentation","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123428313","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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