Pub Date : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263709
Marcos B. Andrade, F. F. da Silva, L. M. C. E. Martins, Hector W. dos S. Oliveira, F. L. L. de Mendonça, R. D. de Sousa
Many people are concerned with physical security and seek support from resources provided by the latest technological advancements, such as security cameras with Internet access associated with biometric people recognition algorithms. However, an isolated camera has a low degree of effectiveness because it has a limited context of information. For instance, detection of missing persons is only effective if multiple cameras are aware of that person is missing. This work proposes a command and control center to allow the coordination of security cameras in a remote and flexible way. This flexibility is achieved because the user can remotely register the actions that each camera must perform, even with the system in operation. It also allows the sharing of a user’s information with multiple cameras. Our tests demonstrate that the system can be installed in an environment with few computational resources, as well as it reacts properly according to the configured parameters.
{"title":"IoT Fog-based Image Matching Monitoring System for Physical Access Control through IP Camera Devices","authors":"Marcos B. Andrade, F. F. da Silva, L. M. C. E. Martins, Hector W. dos S. Oliveira, F. L. L. de Mendonça, R. D. de Sousa","doi":"10.1109/WCNPS50723.2020.9263709","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263709","url":null,"abstract":"Many people are concerned with physical security and seek support from resources provided by the latest technological advancements, such as security cameras with Internet access associated with biometric people recognition algorithms. However, an isolated camera has a low degree of effectiveness because it has a limited context of information. For instance, detection of missing persons is only effective if multiple cameras are aware of that person is missing. This work proposes a command and control center to allow the coordination of security cameras in a remote and flexible way. This flexibility is achieved because the user can remotely register the actions that each camera must perform, even with the system in operation. It also allows the sharing of a user’s information with multiple cameras. Our tests demonstrate that the system can be installed in an environment with few computational resources, as well as it reacts properly according to the configured parameters.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116481727","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263757
Giovanni A. Santos, J. P. J. D. Da Costa, Daniel V. de Lima, M. R. Zanatta, B. Praciano, Gabriel P. M. Pinheiro, F. L. L. de Mendonça, R. D. de Sousa
Autonomous vehicles may save 500.000 lives between 2035 and 2045, since humans cause more than 90% of traffic accidents. In order to have an accurate perception of the environment and to avoid accidents, autonomous vehicles require a positioning estimation with only a few centimeters errors. Therefore, state-of-the-art third generation GNSS systems are not suitable for autonomous vehicle applications. In this paper, we propose an improved localization framework for autonomous vehicles via tensor and antenna array based GNSS receiver. As shown in this paper, in challenging urban scenarios, antenna array based GNSS receivers using tensor based algorithms can provide a positioning five times more accurante than state-of-the-art single antenna based GNSS receivers, reducing the positioning error from 149 cm to 30 cm.
{"title":"Improved localization framework for autonomous vehicles via tensor and antenna array based GNSS receivers","authors":"Giovanni A. Santos, J. P. J. D. Da Costa, Daniel V. de Lima, M. R. Zanatta, B. Praciano, Gabriel P. M. Pinheiro, F. L. L. de Mendonça, R. D. de Sousa","doi":"10.1109/WCNPS50723.2020.9263757","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263757","url":null,"abstract":"Autonomous vehicles may save 500.000 lives between 2035 and 2045, since humans cause more than 90% of traffic accidents. In order to have an accurate perception of the environment and to avoid accidents, autonomous vehicles require a positioning estimation with only a few centimeters errors. Therefore, state-of-the-art third generation GNSS systems are not suitable for autonomous vehicle applications. In this paper, we propose an improved localization framework for autonomous vehicles via tensor and antenna array based GNSS receiver. As shown in this paper, in challenging urban scenarios, antenna array based GNSS receivers using tensor based algorithms can provide a positioning five times more accurante than state-of-the-art single antenna based GNSS receivers, reducing the positioning error from 149 cm to 30 cm.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131776999","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263756
S. M. P. C. Souza, Tito B Rezende, José Nascimento, Levy G. Chaves, Darlinne H P Soto, Soroor Salavati
Bot generated content on social media can spread fake news and hate speech, manipulate public opinion and influence the community on relevant topics, such as elections. Thus, bot detection in social media platforms plays an important role for the health of the platforms and for the well-being of societies. In this work, we approach the detection of bots on Twitter as a binary output problem through the analysis of account features. We propose a pipeline for feature engineering and model training, tuning and selection. We test our pipeline using 3 publicly available bot datasets, comparing the accuracy of all trained models with the model selected at the end of our pipeline.
{"title":"Tuning machine learning models to detect bots on Twitter","authors":"S. M. P. C. Souza, Tito B Rezende, José Nascimento, Levy G. Chaves, Darlinne H P Soto, Soroor Salavati","doi":"10.1109/WCNPS50723.2020.9263756","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263756","url":null,"abstract":"Bot generated content on social media can spread fake news and hate speech, manipulate public opinion and influence the community on relevant topics, such as elections. Thus, bot detection in social media platforms plays an important role for the health of the platforms and for the well-being of societies. In this work, we approach the detection of bots on Twitter as a binary output problem through the analysis of account features. We propose a pipeline for feature engineering and model training, tuning and selection. We test our pipeline using 3 publicly available bot datasets, comparing the accuracy of all trained models with the model selected at the end of our pipeline.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129439214","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263721
V. Almeida, Matheus P Santana, Eric Valter Saconi Barbosa, S. Rondineau
This manuscript proposes a multi-path metallic via through interconnect stripline transition as a Printed Circuit Board (PCB) technology limitations work-around for via setup definition in multi-layer PCB design. The structure operates at the Ku band and presents a strong robustness to layer misalignment within the capabilities of the manufacturers, turning it in a reliable solution for low cost industrial production. The low phase delay differences between paths and homogeneous loss makes it possible for use on true-time-delay beamforming applications, such as passive phased arrays based on Rotman Lenses.
{"title":"Ku Band Metallic Via Through Interconnect–Stripline Capacitive Transitions for Non-Standard PCB Via Setup Using Sequential Build-Up Technology","authors":"V. Almeida, Matheus P Santana, Eric Valter Saconi Barbosa, S. Rondineau","doi":"10.1109/WCNPS50723.2020.9263721","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263721","url":null,"abstract":"This manuscript proposes a multi-path metallic via through interconnect stripline transition as a Printed Circuit Board (PCB) technology limitations work-around for via setup definition in multi-layer PCB design. The structure operates at the Ku band and presents a strong robustness to layer misalignment within the capabilities of the manufacturers, turning it in a reliable solution for low cost industrial production. The low phase delay differences between paths and homogeneous loss makes it possible for use on true-time-delay beamforming applications, such as passive phased arrays based on Rotman Lenses.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130888327","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263733
L. Gontijo, André N. de O. Sol, F. A. O. Nascimento
Amidst the huge data generated from power systems monitoring structures, the demand for better data storage and streaming emerged. In this paper the problem is characterized and a solution is proposed. Utilizing signal processing methods into the field of energy quality, is possible to compress and segment the power signal. Transformations such as wavelets transforms and entropy encoders are applied in a processing pipeline to reduce the bandwidth necessary to transfer the data.
{"title":"Segmentation and Entropy Coding Analysis of a Data Compression System for Power Quality Disturbances","authors":"L. Gontijo, André N. de O. Sol, F. A. O. Nascimento","doi":"10.1109/WCNPS50723.2020.9263733","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263733","url":null,"abstract":"Amidst the huge data generated from power systems monitoring structures, the demand for better data storage and streaming emerged. In this paper the problem is characterized and a solution is proposed. Utilizing signal processing methods into the field of energy quality, is possible to compress and segment the power signal. Transformations such as wavelets transforms and entropy encoders are applied in a processing pipeline to reduce the bandwidth necessary to transfer the data.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116617309","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263723
Luiza M. A. Ribeiro, Gustavo A. Cunha, E. Ribeiro, A. M. Britto, F. Lopes
A Traveling Wave (TW) based propagation analysis of two different transmission line (TL) models available in Electromagnetic Transients Programs (EMTP) is presented in this paper, namely: Bergeron and JMarti models. Firstly, transients induced by a single-phase fault are analyzed assuming ideally transposed (IdT), transposed (T) and untransposed (UnT) TLs. Current signals are evaluated in order to verify differences between TWs propagation when each analyzed model is taken into account. Secondly, the impact of earth resistivity (ρe) has also been investigated. From the obtained results, it is concluded that relevant differences can show up in TWs propagation features due to the applied EMTP TL model, ρe values and also to the modeled transposition scheme, being the ground mode more affected from one case to another.
{"title":"Analysis of Traveling Waves Propagation Characteristics Considering Different Transmission Line EMTP Models","authors":"Luiza M. A. Ribeiro, Gustavo A. Cunha, E. Ribeiro, A. M. Britto, F. Lopes","doi":"10.1109/WCNPS50723.2020.9263723","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263723","url":null,"abstract":"A Traveling Wave (TW) based propagation analysis of two different transmission line (TL) models available in Electromagnetic Transients Programs (EMTP) is presented in this paper, namely: Bergeron and JMarti models. Firstly, transients induced by a single-phase fault are analyzed assuming ideally transposed (IdT), transposed (T) and untransposed (UnT) TLs. Current signals are evaluated in order to verify differences between TWs propagation when each analyzed model is taken into account. Secondly, the impact of earth resistivity (ρe) has also been investigated. From the obtained results, it is concluded that relevant differences can show up in TWs propagation features due to the applied EMTP TL model, ρe values and also to the modeled transposition scheme, being the ground mode more affected from one case to another.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113962929","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263714
P. A. M. de Carvalho, Victor do Prado Brasil, A. de Leles Ferreira Filho, J. A. C. Angarita
This work presents a power grid reduction method that allows the accomplishment of several study cases with different loading conditions regarding the same system by performing a single reduction process. In particular, this technique presents robustness for radial and meshed power grid topology and unbalanced systems modeled with neutral wire, which are not available in related existing publications. Equally important, the evaluation metric employs the phasors voltages instead of just the magnitude itself, as normally seen in the literature. In this fashion, the proposed technique shows the capability to remove more than 2000 buses from a benchmark EPRI feeder with phasorial voltage accuracy of 99% and to speed up 67% its power flow simulation time. Moreover, this paper also exposes a meshed grid reconfiguration and an evaluation of losses from the reduced IEEE 123 buses feeder with photovoltaic distributed generation through a QSTS simulation with a maximum of 1.8% relative losses errors.
{"title":"Generalized Power Grid Reduction Technique","authors":"P. A. M. de Carvalho, Victor do Prado Brasil, A. de Leles Ferreira Filho, J. A. C. Angarita","doi":"10.1109/WCNPS50723.2020.9263714","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263714","url":null,"abstract":"This work presents a power grid reduction method that allows the accomplishment of several study cases with different loading conditions regarding the same system by performing a single reduction process. In particular, this technique presents robustness for radial and meshed power grid topology and unbalanced systems modeled with neutral wire, which are not available in related existing publications. Equally important, the evaluation metric employs the phasors voltages instead of just the magnitude itself, as normally seen in the literature. In this fashion, the proposed technique shows the capability to remove more than 2000 buses from a benchmark EPRI feeder with phasorial voltage accuracy of 99% and to speed up 67% its power flow simulation time. Moreover, this paper also exposes a meshed grid reconfiguration and an evaluation of losses from the reduced IEEE 123 buses feeder with photovoltaic distributed generation through a QSTS simulation with a maximum of 1.8% relative losses errors.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125095347","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263749
Matheus P Santana, Eric Valter Saconi Barbosa, S. Rondineau
This manuscript presents the design of two microstrip coupled open-loop resonator bandpass filters using a square loop-resonator, also know as splitring resonators, to be used in radio frequency Front-Ends. In addition, a microstrip diplexer using these cells is also detailed. The devices operate in ku band, using the frequencies 11.7–12.2GHz, to the receiver channel, and 14–14.5GHz, to the transmitter channel. All the design is made considering low-cost industrial manufacturing tolerances. A Monte Carlo analysis is performed to verify the sensibility of the device due to the manufacturing capabilities. The measurement and simulation curves agree with a good level of acceptance, diverging each other in just 1.7dB in the passband, in the worst case.
{"title":"Design of Ku-Band Filters and Diplexer for a Heterodyne Transceiver Using Coupled Open-Loop Resonator Cells","authors":"Matheus P Santana, Eric Valter Saconi Barbosa, S. Rondineau","doi":"10.1109/WCNPS50723.2020.9263749","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263749","url":null,"abstract":"This manuscript presents the design of two microstrip coupled open-loop resonator bandpass filters using a square loop-resonator, also know as splitring resonators, to be used in radio frequency Front-Ends. In addition, a microstrip diplexer using these cells is also detailed. The devices operate in ku band, using the frequencies 11.7–12.2GHz, to the receiver channel, and 14–14.5GHz, to the transmitter channel. All the design is made considering low-cost industrial manufacturing tolerances. A Monte Carlo analysis is performed to verify the sensibility of the device due to the manufacturing capabilities. The measurement and simulation curves agree with a good level of acceptance, diverging each other in just 1.7dB in the passband, in the worst case.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116736920","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263765
Guilherme Félix de Andrade, Eric Valter Saconi Barbosa, S. Rondineau
This work presents both a systemic analysis and measurements of a heterodyne radiofrequency front-end receiver for satellite communications in Ku-Band alongside with the design and characterization of its single stage Low Noise Amplifier (LNA).
{"title":"RF Front-End Receiver for Vehicular Satellite Communications and LNA GaAs FET Design in Ku-Band","authors":"Guilherme Félix de Andrade, Eric Valter Saconi Barbosa, S. Rondineau","doi":"10.1109/WCNPS50723.2020.9263765","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263765","url":null,"abstract":"This work presents both a systemic analysis and measurements of a heterodyne radiofrequency front-end receiver for satellite communications in Ku-Band alongside with the design and characterization of its single stage Low Noise Amplifier (LNA).","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122536008","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 : 2020-11-12DOI: 10.1109/WCNPS50723.2020.9263766
Jonas V. de Souza, G. N. Lopes, J. Vieira, E. Asada
Several challenges for generation, transmission, and distribution of electricity arise with the expansion of electrical Distribution Systems (DSs). Continuity and the ability to serve end consumers represent a significant challenge for companies responsible for supplying electricity. Therefore, the study of the improvement of effective fault identification techniques, more specifically of High Impedance Faults (HIFs), has grown substantially. HIFs are not identified by conventional protection as this type of fault has currents with values close to those in the steady-state condition in DSs. Furthermore, due to the electric arc, the HIFs offer danger to living beings and network devices. To the date, there is no fully effective protection to detect it. Therefore, this paper aims to propose a methodology capable of identifying HIFs and classifying power quality events. To this end, the proposed technique uses low-order harmonics extracted by Fourier Transform (FT) from the current signals registered at the substation of a DS as input data for a multilayer Artificial Neural Network (ANN). The tests consisted of simulating HIFs along with several system buses and evaluating false positives (non-HIF events) by simulating frequent events in DSs. The results proved the proposed technique is promising, with a high detection rate even with the addition of noise to the signals.
{"title":"High Impedance Fault Detection in Distribution Systems: An Approach Based on Fourier Transform and Artificial Neural Networks","authors":"Jonas V. de Souza, G. N. Lopes, J. Vieira, E. Asada","doi":"10.1109/WCNPS50723.2020.9263766","DOIUrl":"https://doi.org/10.1109/WCNPS50723.2020.9263766","url":null,"abstract":"Several challenges for generation, transmission, and distribution of electricity arise with the expansion of electrical Distribution Systems (DSs). Continuity and the ability to serve end consumers represent a significant challenge for companies responsible for supplying electricity. Therefore, the study of the improvement of effective fault identification techniques, more specifically of High Impedance Faults (HIFs), has grown substantially. HIFs are not identified by conventional protection as this type of fault has currents with values close to those in the steady-state condition in DSs. Furthermore, due to the electric arc, the HIFs offer danger to living beings and network devices. To the date, there is no fully effective protection to detect it. Therefore, this paper aims to propose a methodology capable of identifying HIFs and classifying power quality events. To this end, the proposed technique uses low-order harmonics extracted by Fourier Transform (FT) from the current signals registered at the substation of a DS as input data for a multilayer Artificial Neural Network (ANN). The tests consisted of simulating HIFs along with several system buses and evaluating false positives (non-HIF events) by simulating frequent events in DSs. The results proved the proposed technique is promising, with a high detection rate even with the addition of noise to the signals.","PeriodicalId":385668,"journal":{"name":"2020 Workshop on Communication Networks and Power Systems (WCNPS)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134093557","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：