Pub Date : 2013-05-06DOI: 10.1109/I2MTC.2013.6555704
Murat Sean McKeown, S. Trabelsi, E. Tollner
Microwave moisture sensing provides a means to determine nondestructively the amount of water in materials. This is accomplished through the correlation of dielectric properties with moisture in the material. In this study, linear relationships between a density-independent function of the dielectric properties and moisture content of minced Vidalia onions, with slope dependent on moisture range, is identified. This allows prediction of moisture contents between 6% and 92%. Results showed the prediction of moisture content with a coefficient of determination of 0.976. The measurements and techniques presented in this study constitute a foundation for the development of a stand-alone sensor.
{"title":"Microwave moisture sensing through use of a piecewise density-independent function","authors":"Murat Sean McKeown, S. Trabelsi, E. Tollner","doi":"10.1109/I2MTC.2013.6555704","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555704","url":null,"abstract":"Microwave moisture sensing provides a means to determine nondestructively the amount of water in materials. This is accomplished through the correlation of dielectric properties with moisture in the material. In this study, linear relationships between a density-independent function of the dielectric properties and moisture content of minced Vidalia onions, with slope dependent on moisture range, is identified. This allows prediction of moisture contents between 6% and 92%. Results showed the prediction of moisture content with a coefficient of determination of 0.976. The measurements and techniques presented in this study constitute a foundation for the development of a stand-alone sensor.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"20 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":"122274562","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.2013.6555419
G. Vakulya, G. Simon
In this paper a TDMA based routing scheme is proposed for such wireless sensor networks, where nodes form multiple connected cycles. The proposed method provides fault tolerance, guaranteed delivery times, and low power consumption. The paper discusses the routing scheme and its implementation details, and provides several performance tests.
{"title":"Extended round-robin TDMA scheduling scheme for wireless sensor networks","authors":"G. Vakulya, G. Simon","doi":"10.1109/I2MTC.2013.6555419","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555419","url":null,"abstract":"In this paper a TDMA based routing scheme is proposed for such wireless sensor networks, where nodes form multiple connected cycles. The proposed method provides fault tolerance, guaranteed delivery times, and low power consumption. The paper discusses the routing scheme and its implementation details, and provides several performance tests.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"81 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":"132559191","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.2013.6555686
R. Vafaei, J. Crebier, N. Rouger
This paper demonstrates an accurate measurement procedure to characterize the DC and AC performance of an optical detector designed for monolithic integration with a 600 V vertical power MOS transistor. The spectral quantum efficiency (QE) from 400 nm up to 1 μm wavelengths has been measured. A QE of 26% in the 450 nm - 520 nm wavelength range was achieved. The developed setup and measurement procedures can be used for diced samples, packaged devices, and on-wafer probing (maximum size: 4” wafers); furthermore, it is equipped with temperature control. The integrated optical detectors (IOD) key phenomena have been investigated for a wide range of wavelengths and biasing conditions, both experimentally and numerically. Simulation results as well as experimental results are presented and compared.
{"title":"Performance measurements of an optical detector designed for monolithic integration with a power VDMOS","authors":"R. Vafaei, J. Crebier, N. Rouger","doi":"10.1109/I2MTC.2013.6555686","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555686","url":null,"abstract":"This paper demonstrates an accurate measurement procedure to characterize the DC and AC performance of an optical detector designed for monolithic integration with a 600 V vertical power MOS transistor. The spectral quantum efficiency (QE) from 400 nm up to 1 μm wavelengths has been measured. A QE of 26% in the 450 nm - 520 nm wavelength range was achieved. The developed setup and measurement procedures can be used for diced samples, packaged devices, and on-wafer probing (maximum size: 4” wafers); furthermore, it is equipped with temperature control. The integrated optical detectors (IOD) key phenomena have been investigated for a wide range of wavelengths and biasing conditions, both experimentally and numerically. Simulation results as well as experimental results are presented and compared.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"35 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":"134085830","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.2013.6555555
D. Belega, D. Petri
In this paper the performances of the synchrophasor estimators provided by the Weighted Least Squares (WLS) algorithm based on the cosine windows are analyzed under steady-state, dynamic, and transient conditions. Two-, three-, and four-cycle observation interval lengths are considered. Specifically, steady-state accuracy is assessed by considering the effect of both off-nominal frequency offsets and harmonics. Conversely, dynamic conditions are modeled as sinusoidal amplitude and/or phase modulations, or linear frequency ramps. According to the IEEE Standard C37.118.1-2011 about synchrophasors for power systems, the Total Vector Error (TVE) is employed as accuracy parameter and the achieved results are compared with the maximum allowed values specified in the Standard for P- or M-class compliance. Finally, estimator response time to amplitude or phase steps is analyzed. The achieved results allow an overall assessment of the WLS synchrophasor estimator performances.
{"title":"Performance of synchrophasor measurements provided by the Weighted Least Squares approach","authors":"D. Belega, D. Petri","doi":"10.1109/I2MTC.2013.6555555","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555555","url":null,"abstract":"In this paper the performances of the synchrophasor estimators provided by the Weighted Least Squares (WLS) algorithm based on the cosine windows are analyzed under steady-state, dynamic, and transient conditions. Two-, three-, and four-cycle observation interval lengths are considered. Specifically, steady-state accuracy is assessed by considering the effect of both off-nominal frequency offsets and harmonics. Conversely, dynamic conditions are modeled as sinusoidal amplitude and/or phase modulations, or linear frequency ramps. According to the IEEE Standard C37.118.1-2011 about synchrophasors for power systems, the Total Vector Error (TVE) is employed as accuracy parameter and the achieved results are compared with the maximum allowed values specified in the Standard for P- or M-class compliance. Finally, estimator response time to amplitude or phase steps is analyzed. The achieved results allow an overall assessment of the WLS synchrophasor estimator performances.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"187 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134093951","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.2013.6555437
L. Eren, M. Devaney
Motor Current Signature Analysis (MCSA) is one of the most widely used methods in monitoring condition of induction motors. Traditionally, the stator current is preprocessed by notch filters to suppress line fundamental frequency. Then, the fast Fourier transform is utilized for the spectral analysis of the preprocessed stator current in most applications. However, this approach has a shortcoming in the analysis of non-stationary signals such as stator current under varying load conditions. The use of wavelet transform is suggested for providing better analysis results in recently published studies. Both approaches use some preprocessing of stator current in the analysis that is very sensitive to even slightest variations in sampling frequency. The resampling of current data at an exact integer multiple of line frequency is proposed in this study to improve the overall fault detection performance.
{"title":"Effect of current resampling in Motor Current Signature Analysis","authors":"L. Eren, M. Devaney","doi":"10.1109/I2MTC.2013.6555437","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555437","url":null,"abstract":"Motor Current Signature Analysis (MCSA) is one of the most widely used methods in monitoring condition of induction motors. Traditionally, the stator current is preprocessed by notch filters to suppress line fundamental frequency. Then, the fast Fourier transform is utilized for the spectral analysis of the preprocessed stator current in most applications. However, this approach has a shortcoming in the analysis of non-stationary signals such as stator current under varying load conditions. The use of wavelet transform is suggested for providing better analysis results in recently published studies. Both approaches use some preprocessing of stator current in the analysis that is very sensitive to even slightest variations in sampling frequency. The resampling of current data at an exact integer multiple of line frequency is proposed in this study to improve the overall fault detection performance.","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":"131669209","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.2013.6555405
G. Gross, M. Landi
Energy independence, reduction of CO2 emissions and increasing oil prices are the key drivers for the development of new transportation technologies, among which the Battery Electric Vehicles. Instead of representing merely a load, they can provide ancillary services to the power grid: such integration of vehicles into the grid is known as V2G. The continuous charging and discharging of the batteries to provide services to the grid tends to degrade the vehicle batteries, decreasing their maximum life. Therefore it is of interest developing a management strategy that tends to maximize the life of the batteries. To this end it is of fundamental importance being able to assess the state of health of a battery. In this paper a methodology for the measurement of the health is described, and the first experimental results are provided.
{"title":"Measurement of a health index for Li-Ion batteries","authors":"G. Gross, M. Landi","doi":"10.1109/I2MTC.2013.6555405","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555405","url":null,"abstract":"Energy independence, reduction of CO2 emissions and increasing oil prices are the key drivers for the development of new transportation technologies, among which the Battery Electric Vehicles. Instead of representing merely a load, they can provide ancillary services to the power grid: such integration of vehicles into the grid is known as V2G. The continuous charging and discharging of the batteries to provide services to the grid tends to degrade the vehicle batteries, decreasing their maximum life. Therefore it is of interest developing a management strategy that tends to maximize the life of the batteries. To this end it is of fundamental importance being able to assess the state of health of a battery. In this paper a methodology for the measurement of the health is described, and the first experimental results are provided.","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":"128888817","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.2013.6555387
T. Addabbo, F. Bertocci, A. Fort, M. Mugnaini, S. Rocchi, V. Vignoli
The materials exploited for the development of gas conductometric sensors are often n-type semiconductors as in the case, e.g., of SnO2. Several materials studied in the last years for this application behave as p-type semiconductors (e.g. CuO, Cr2O3, Kor AgHollandites). In this work the authors present a novel surface state model for p-type, large grained, thick film materials, with a specific reference to Kor Ag- Hollandites, which accounts for the material response to CO in dry and humid N2, and in dry and humid air. A reliable and compact model of this type is of the utmost utility from several points of view, including the development of measurement systems based on gas sensors. The availability of a simulation tool able to accurately predict the sensor behavior enables the replacement of experimental tuning with simulations, and can significantly speed-up sensor-based system development and guarantee better performance.
用于开发气体电导传感器的材料通常是n型半导体，例如SnO2。在过去的几年里，研究了几种用于这种应用的材料表现为p型半导体(例如CuO, Cr2O3, Kor AgHollandites)。在这项工作中，作者提出了一种新的p型，大颗粒，厚膜材料的表面状态模型，特别提到了Kor Ag- Hollandites，它解释了材料在干燥和潮湿的N2以及干燥和潮湿的空气中对CO的响应。从几个角度来看，这种类型的可靠和紧凑的模型具有最大的实用性，包括基于气体传感器的测量系统的发展。能够准确预测传感器行为的仿真工具的可用性使得用仿真代替实验调谐成为可能，并且可以显着加快基于传感器的系统的开发并保证更好的性能。
{"title":"Surface state model for metal oxide p-type conductometric CO sensors","authors":"T. Addabbo, F. Bertocci, A. Fort, M. Mugnaini, S. Rocchi, V. Vignoli","doi":"10.1109/I2MTC.2013.6555387","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555387","url":null,"abstract":"The materials exploited for the development of gas conductometric sensors are often n-type semiconductors as in the case, e.g., of SnO2. Several materials studied in the last years for this application behave as p-type semiconductors (e.g. CuO, Cr2O3, Kor AgHollandites). In this work the authors present a novel surface state model for p-type, large grained, thick film materials, with a specific reference to Kor Ag- Hollandites, which accounts for the material response to CO in dry and humid N2, and in dry and humid air. A reliable and compact model of this type is of the utmost utility from several points of view, including the development of measurement systems based on gas sensors. The availability of a simulation tool able to accurately predict the sensor behavior enables the replacement of experimental tuning with simulations, and can significantly speed-up sensor-based system development and guarantee better performance.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"54 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":"124518080","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.2013.6555677
L. Chao, M. Afsar
Barium and Strontium Ferrites exhibit strong magnetic anisotropy at millimeter waves due to their hexagonal configuration. Barium and Strontium Ferrite powders with different particle diameter are measured in millimeter wave frequency range. A Quasi-optical spectrometer in transmission mode powered by high power backward oscillator is employed to measure the transmittance of these powder samples. The ferromagnetic resonance is determined from the transmittance spectra. For the nano-size powders the dip in the transmittance becomes weaker and sharper. The dip or the minimum in transmittance spectrum which is essentially the resonance peak moves to lower frequency. It is mainly due to the decrease in domain size. Possible errors in the evaluation of permittivity and permeability are analyzed.
{"title":"Complex dielectric permittivity and magnetic permeability measurement of ferrite powders at millimeter wavelength","authors":"L. Chao, M. Afsar","doi":"10.1109/I2MTC.2013.6555677","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555677","url":null,"abstract":"Barium and Strontium Ferrites exhibit strong magnetic anisotropy at millimeter waves due to their hexagonal configuration. Barium and Strontium Ferrite powders with different particle diameter are measured in millimeter wave frequency range. A Quasi-optical spectrometer in transmission mode powered by high power backward oscillator is employed to measure the transmittance of these powder samples. The ferromagnetic resonance is determined from the transmittance spectra. For the nano-size powders the dip in the transmittance becomes weaker and sharper. The dip or the minimum in transmittance spectrum which is essentially the resonance peak moves to lower frequency. It is mainly due to the decrease in domain size. Possible errors in the evaluation of permittivity and permeability are analyzed.","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":"115051330","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.2013.6555596
A. L. Torla, Sheroz Khan, A. G. Muthalif, A. Azman, Yasir Mohd-Mustafah
RFID tags, sensors embedded with buried devices and biomedical implants all operate at low voltage levels due to power limitations. The ever increasing use these embedded devices has also created a demand in the industry for low-voltage power supplies. Since many of these circuits are mobile in nature and so are bound to operate in many different environments, the power supply must also be capable of ensuring a stable voltage output even under adverse conditions. This paper analyzes and simulates a power supply circuit that promises a low ripple factor with an element of spike-blocking capability. It centers on a phase-modulation technique that effectively cancels out 99.6% of ripples when operating with a 100 mV ac input at a frequency of 10 kHz. This active noise-cancellation technique allows for a more stable voltage output. It also has a limited inbuilt capability to block spikes. A 100 mV injected spike is brought down to only 6 mV without the use of other damping circuits. This work is therefore capable of damping a large part of the variations in the input voltage, even at low voltages.
{"title":"Low voltage DC power supply with spike-blocking features","authors":"A. L. Torla, Sheroz Khan, A. G. Muthalif, A. Azman, Yasir Mohd-Mustafah","doi":"10.1109/I2MTC.2013.6555596","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555596","url":null,"abstract":"RFID tags, sensors embedded with buried devices and biomedical implants all operate at low voltage levels due to power limitations. The ever increasing use these embedded devices has also created a demand in the industry for low-voltage power supplies. Since many of these circuits are mobile in nature and so are bound to operate in many different environments, the power supply must also be capable of ensuring a stable voltage output even under adverse conditions. This paper analyzes and simulates a power supply circuit that promises a low ripple factor with an element of spike-blocking capability. It centers on a phase-modulation technique that effectively cancels out 99.6% of ripples when operating with a 100 mV ac input at a frequency of 10 kHz. This active noise-cancellation technique allows for a more stable voltage output. It also has a limited inbuilt capability to block spikes. A 100 mV injected spike is brought down to only 6 mV without the use of other damping circuits. This work is therefore capable of damping a large part of the variations in the input voltage, even at low voltages.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"56 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":"122046510","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.2013.6555712
S. Ferrari, M. Lazzaroni, V. Piuri, L. Cristaldi, M. Faifer
It is well known that the knowledge of solar radiation represents a key for managing photovoltaic (PV) plants. In a smart grid scenario to predict the energy production can be considered a milestone. However, the unsteadiness of the weather phenomena makes the prediction of the energy produced by the solar radiation conversion process a difficult task. Starting from this considerations, the use of the data collected in the past represents only the first step in order to evaluate the variability both in a daily and seasonal fashion. In order to have a stronger dataset a multi-year observation is mandatory. In this paper, several autoregressive models are challenged on a two-year ground global horizontal radiation dataset measured in Milan, and the results are compared with those of simple predictor.
{"title":"Statistical models approach for solar radiation prediction","authors":"S. Ferrari, M. Lazzaroni, V. Piuri, L. Cristaldi, M. Faifer","doi":"10.1109/I2MTC.2013.6555712","DOIUrl":"https://doi.org/10.1109/I2MTC.2013.6555712","url":null,"abstract":"It is well known that the knowledge of solar radiation represents a key for managing photovoltaic (PV) plants. In a smart grid scenario to predict the energy production can be considered a milestone. However, the unsteadiness of the weather phenomena makes the prediction of the energy produced by the solar radiation conversion process a difficult task. Starting from this considerations, the use of the data collected in the past represents only the first step in order to evaluate the variability both in a daily and seasonal fashion. In order to have a stronger dataset a multi-year observation is mandatory. In this paper, several autoregressive models are challenged on a two-year ground global horizontal radiation dataset measured in Milan, and the results are compared with those of simple predictor.","PeriodicalId":432388,"journal":{"name":"2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)","volume":"18 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":"123985096","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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