Pub Date : 2019-07-01DOI: 10.1109/TSP.2019.8768866
M. Nedelchev, B. Stošić, N. Dončov, A. Kolev
In this paper, a possible solution for multimethod modeling of wideband branch-line hybrid is presented. Solution is based on the wave digital approach taking into account directly the scattering parameters of the microstrip lines with defected ground structures. Defected ground structure is used to improve the performances and the frequency responses of the designed wideband hybrid. As an example of application, a tri-section wideband branch-line hybrid for operating at center frequency of 2400 MHz has been design and fabricated. The predicted and measured results show very good agreement.
{"title":"Tri-Section Wideband Branch-Line Hybrid: Design, Simulation Technique and Measurement","authors":"M. Nedelchev, B. Stošić, N. Dončov, A. Kolev","doi":"10.1109/TSP.2019.8768866","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768866","url":null,"abstract":"In this paper, a possible solution for multimethod modeling of wideband branch-line hybrid is presented. Solution is based on the wave digital approach taking into account directly the scattering parameters of the microstrip lines with defected ground structures. Defected ground structure is used to improve the performances and the frequency responses of the designed wideband hybrid. As an example of application, a tri-section wideband branch-line hybrid for operating at center frequency of 2400 MHz has been design and fabricated. The predicted and measured results show very good agreement.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130429221","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768884
Eva Lieskovská, Maroš Jakubec, R. Jarina
This article presents a design of the system for acoustic event detection. The proposed pilot application is focused on child’s emotion/behaviour related sounds such as cry and laugh detection. Monitoring behaviour and safety of small children is particularly crucial in in-car environment and in households. The proposed application is based on Gaussian Mixture Model - Universal Background Model approach. The system is optimized by balancing false acceptance and false rejection rate. The classification accuracy of 71.6% was achieved although the system was trained only on small amount of data. The proposed approach has low computing and memory requirements thus is also suitable for implementation in embedded systems.
{"title":"Acoustic surveillance system for children’s emotion detection","authors":"Eva Lieskovská, Maroš Jakubec, R. Jarina","doi":"10.1109/TSP.2019.8768884","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768884","url":null,"abstract":"This article presents a design of the system for acoustic event detection. The proposed pilot application is focused on child’s emotion/behaviour related sounds such as cry and laugh detection. Monitoring behaviour and safety of small children is particularly crucial in in-car environment and in households. The proposed application is based on Gaussian Mixture Model - Universal Background Model approach. The system is optimized by balancing false acceptance and false rejection rate. The classification accuracy of 71.6% was achieved although the system was trained only on small amount of data. The proposed approach has low computing and memory requirements thus is also suitable for implementation in embedded systems.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134389575","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 : 2019-07-01DOI: 10.1109/TSP.2019.8769046
Arslan Ali, G. Fischer
This paper presents computationally efficient fake base station (FBS) detection scheme through higher order statistical analysis at the user equipment (UE) side. In the proposed RF fingerprinting detection scheme, the UE inspects surrounding base stations (BS) by first extracting noise from the received signal through novel sample-based parametric estimation technique and then measuring the noise structuredness with the aid of fourth order moment i.e. kurtosis over the estimated noise samples. This reveals unique RF fingerprints of the legitimized regular base station (RBS) in terms of hardware impairments and resultantly indicates minimal impact from the non-linearities. In contrary, FBS exhibits different RF fingerprints containing larger amount of non-linearities in the received signal due to presence of large impairments. With the help of actual measurement results from RBS and various software defined radio (SDR) based FBS at different cellular standards and by defining a critical threshold of detection, we show that an FBS deviates a lot from the ideal Gaussian noise distribution and constitutes of multivariate distributions, whereas an RBS show minimal deviation from the reference and contains univariate noise distribution. We further calculate the observation sample time required to detect an FBS in an optimal MMSE sense and indicate with the help of results that the minimum time to identify a fake cell is 10ms.
{"title":"Enabling Fake Base Station Detection through Sample-based Higher Order Noise Statistics","authors":"Arslan Ali, G. Fischer","doi":"10.1109/TSP.2019.8769046","DOIUrl":"https://doi.org/10.1109/TSP.2019.8769046","url":null,"abstract":"This paper presents computationally efficient fake base station (FBS) detection scheme through higher order statistical analysis at the user equipment (UE) side. In the proposed RF fingerprinting detection scheme, the UE inspects surrounding base stations (BS) by first extracting noise from the received signal through novel sample-based parametric estimation technique and then measuring the noise structuredness with the aid of fourth order moment i.e. kurtosis over the estimated noise samples. This reveals unique RF fingerprints of the legitimized regular base station (RBS) in terms of hardware impairments and resultantly indicates minimal impact from the non-linearities. In contrary, FBS exhibits different RF fingerprints containing larger amount of non-linearities in the received signal due to presence of large impairments. With the help of actual measurement results from RBS and various software defined radio (SDR) based FBS at different cellular standards and by defining a critical threshold of detection, we show that an FBS deviates a lot from the ideal Gaussian noise distribution and constitutes of multivariate distributions, whereas an RBS show minimal deviation from the reference and contains univariate noise distribution. We further calculate the observation sample time required to detect an FBS in an optimal MMSE sense and indicate with the help of results that the minimum time to identify a fake cell is 10ms.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133254254","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768810
P. Faragó, R. Groza, Liliana Ivanciu, S. Hintea
With the increase in the number of nodes connected to a wireless body area network (WBAN), transmitting biomedical data with the purpose of continuous health monitoring, authentication is a key element to maintain confidentiality in an open environment. In this context, this paper investigates the employment of biometrics extracted from biomedical signals, namely electrocardiogram, photopletysmogram and electromyogram, monitored by the WBAN nodes for user identification. The proposed biometric feature extraction technique is based on cross-correlating the biomedical signal to a reference signal. As such, biometrics extraction is solved with a procedure similar to the morphological analysis of the biomedical signal. Simulation results prove the applicability of the proposed technique.
{"title":"A Correlation-based Biometric Identification Technique for ECG, PPG and EMG","authors":"P. Faragó, R. Groza, Liliana Ivanciu, S. Hintea","doi":"10.1109/TSP.2019.8768810","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768810","url":null,"abstract":"With the increase in the number of nodes connected to a wireless body area network (WBAN), transmitting biomedical data with the purpose of continuous health monitoring, authentication is a key element to maintain confidentiality in an open environment. In this context, this paper investigates the employment of biometrics extracted from biomedical signals, namely electrocardiogram, photopletysmogram and electromyogram, monitored by the WBAN nodes for user identification. The proposed biometric feature extraction technique is based on cross-correlating the biomedical signal to a reference signal. As such, biometrics extraction is solved with a procedure similar to the morphological analysis of the biomedical signal. Simulation results prove the applicability of the proposed technique.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115460334","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768876
Ahmed A. F. Youssef, P. E. Abi-Char
In indoor positioning system, the user’s location is estimated based on user fingerprints database collected. The received signal from a user at a certain location is compared with all database entries and the best match is selected as the correct estimation. For a given number of access points (APs), optimizing the locations of APs can significantly improve the performance of user location estimation. In this work, the probability of correct estimation is analyzed based on APs location. Both analytical expressions and numerical results are presented and discussed. It has been shown that the probability of correct estimation is highly affected by the APs locations. Furthermore, a new technique is proposed to remarkably reduce the search-cost when comparing a received user signal to the data-base. The performance of the system is analyzed considering different APs locations, different user locations, and different noise variances. It is shown that user’s location estimation is significantly improved when compared to existing techniques.
{"title":"The Impact of Access Points Placement on Indoor Positioning Systems: A Probability-Based Approach","authors":"Ahmed A. F. Youssef, P. E. Abi-Char","doi":"10.1109/TSP.2019.8768876","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768876","url":null,"abstract":"In indoor positioning system, the user’s location is estimated based on user fingerprints database collected. The received signal from a user at a certain location is compared with all database entries and the best match is selected as the correct estimation. For a given number of access points (APs), optimizing the locations of APs can significantly improve the performance of user location estimation. In this work, the probability of correct estimation is analyzed based on APs location. Both analytical expressions and numerical results are presented and discussed. It has been shown that the probability of correct estimation is highly affected by the APs locations. Furthermore, a new technique is proposed to remarkably reduce the search-cost when comparing a received user signal to the data-base. The performance of the system is analyzed considering different APs locations, different user locations, and different noise variances. It is shown that user’s location estimation is significantly improved when compared to existing techniques.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124538459","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768880
Roger Bertran-Capdevila, E. Sesa-Nogueras, M. Faúndez-Zanuy
In this paper we present a software tool for displaying and analyzing handwriting signals recorded by digitizing devices that capture both in-air and on-surface trajectories. This tool has two salient features: it can visualize the invisible trajectories described by the writing device while it is not exerting any pressure on the writing surface and it can calculate entropies and fractal dimensions, two measures that are relevant when analyzing handwriting signals for health-related purposes, mainly in the diagnose of some neurodegenerative conditions like Parkinson’s disease and Alzheimer’s disease.
{"title":"SVC ANALYTICS a Software for Plotting and Extracting Features from Online Handwriting Signals","authors":"Roger Bertran-Capdevila, E. Sesa-Nogueras, M. Faúndez-Zanuy","doi":"10.1109/TSP.2019.8768880","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768880","url":null,"abstract":"In this paper we present a software tool for displaying and analyzing handwriting signals recorded by digitizing devices that capture both in-air and on-surface trajectories. This tool has two salient features: it can visualize the invisible trajectories described by the writing device while it is not exerting any pressure on the writing surface and it can calculate entropies and fractal dimensions, two measures that are relevant when analyzing handwriting signals for health-related purposes, mainly in the diagnose of some neurodegenerative conditions like Parkinson’s disease and Alzheimer’s disease.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114431480","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768821
L. H. Teixeira, Árpád Huszák
A key aspect to fill the demand for intelligent and connected vehicle solutions in C-ITS (Cooperative Intelligent Transport Systems), is to improve the network communication technologies existing nowadays. The actual radio network technologies may not support this future demand. One option to minimize this problem is to use extra information, like navigation GPS route, and use intelligent algorithms to choose the better infrastructure. In this paper we will show our proposed SISS algorithm and compare with TOPSIS algorithm to select network, using and not using the GPS route data, applying the requirements of different applications in the network selection. We present simulation results to show the differences of the proposed approach.
{"title":"Preemptive Network Selection for V2V Communication","authors":"L. H. Teixeira, Árpád Huszák","doi":"10.1109/TSP.2019.8768821","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768821","url":null,"abstract":"A key aspect to fill the demand for intelligent and connected vehicle solutions in C-ITS (Cooperative Intelligent Transport Systems), is to improve the network communication technologies existing nowadays. The actual radio network technologies may not support this future demand. One option to minimize this problem is to use extra information, like navigation GPS route, and use intelligent algorithms to choose the better infrastructure. In this paper we will show our proposed SISS algorithm and compare with TOPSIS algorithm to select network, using and not using the GPS route data, applying the requirements of different applications in the network selection. We present simulation results to show the differences of the proposed approach.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114465337","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768843
N. Herencsar, A. Kartci, H. A. Yildiz, R. Sotner, Jan Dvorak, D. Kubánek, J. Jerabek, J. Koton
In this paper, a fractional-order capacitor (FOC) of an order $lambda$=0.89 (i.e. constant phase angle -80.1 degree) was emulated via Valsa RC network with five branches. The network component values were optimized using modified least squares quadratic method in a wide frequency range of 100 mHz-1kHz (i.e. 4 decades) and maximum relative phase error 0.78% was obtained. The design specification corresponds to a speed control system of an armature controlled DC motor, which is often used in control theory. Overall performance evaluation shows the product of evaluated key features (e.g. phase angle deviation and absolute values of relative phase, impedance, and pseudocapacitance errors) for the optimized FOC is 13.3% less than the one obtained via Valsa approximation. The behavior of Op-Amp-based non-inverting configurations of analogue fractional-order integral operator $s^{-lambda}$ employing the optimized FOC, where 0<$lambda$<1, is compared. The behavior of studied integrator circuits is confirmed by SPICE simulations using the readily available Texas Instruments TL072 low-noise Op-Amp macromodel, which is commonly used in electronics.
{"title":"Comparative Study of Op-Amp-based Integrators Suitable for Fractional -Order Controller Design","authors":"N. Herencsar, A. Kartci, H. A. Yildiz, R. Sotner, Jan Dvorak, D. Kubánek, J. Jerabek, J. Koton","doi":"10.1109/TSP.2019.8768843","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768843","url":null,"abstract":"In this paper, a fractional-order capacitor (FOC) of an order $lambda$=0.89 (i.e. constant phase angle -80.1 degree) was emulated via Valsa RC network with five branches. The network component values were optimized using modified least squares quadratic method in a wide frequency range of 100 mHz-1kHz (i.e. 4 decades) and maximum relative phase error 0.78% was obtained. The design specification corresponds to a speed control system of an armature controlled DC motor, which is often used in control theory. Overall performance evaluation shows the product of evaluated key features (e.g. phase angle deviation and absolute values of relative phase, impedance, and pseudocapacitance errors) for the optimized FOC is 13.3% less than the one obtained via Valsa approximation. The behavior of Op-Amp-based non-inverting configurations of analogue fractional-order integral operator $s^{-lambda}$ employing the optimized FOC, where 0<$lambda$<1, is compared. The behavior of studied integrator circuits is confirmed by SPICE simulations using the readily available Texas Instruments TL072 low-noise Op-Amp macromodel, which is commonly used in electronics.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114586625","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 : 2019-07-01DOI: 10.1109/TSP.2019.8769029
A. H. Tacuri, Alberth Tamo
This paper presents a probabilistic model to assess the co-channel interference produced by multiple FWA transmitters into a HAPS victim receiver. To avoid the worst assumptions usually considered in traditional interference calculation methods, in the proposed approach the geographic positions of FWA base and subscriber stations are characterized by two dimensional point processes. Two specific interfering scenarios are considered and, in each of them, coordination distances obtained with the proposed model are compared to those resulting from the traditional deterministic interference calculation methods.
{"title":"Probabilistic Model for the Interference Analysis from FWA-TDMA Systems Into HAPS","authors":"A. H. Tacuri, Alberth Tamo","doi":"10.1109/TSP.2019.8769029","DOIUrl":"https://doi.org/10.1109/TSP.2019.8769029","url":null,"abstract":"This paper presents a probabilistic model to assess the co-channel interference produced by multiple FWA transmitters into a HAPS victim receiver. To avoid the worst assumptions usually considered in traditional interference calculation methods, in the proposed approach the geographic positions of FWA base and subscriber stations are characterized by two dimensional point processes. Two specific interfering scenarios are considered and, in each of them, coordination distances obtained with the proposed model are compared to those resulting from the traditional deterministic interference calculation methods.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123515438","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 : 2019-07-01DOI: 10.1109/TSP.2019.8768891
David Meltzer, D. Luengo
Biometry is becoming increasingly important in order to identify or authenticate individuals. Since the seminar work of Biel et at. in 1999 and 2001, the feasibility of using the electrocardiogram (ECG) for biometric recognition has been considered by several authors. Both fiducial methods, which are based on using fiducial points related to the detected QRS complexes, and non-fiducial methods, which do not require the extraction of the QRS complexes from the signals, have been considered. However, the feasibility of ECG-based biometry is still unclear, as the results from different studies are difficult to compare. In this paper, we concentrate on fiducial methods, comparing the performance of several classifiers and dimensionality reduction techniques on a publicly available dataset. Our results show that ECG-based biometry is indeed a feasible alternative to other widely used biometric traits, since an accuracy above 99.95% can be attained with the appropriate choice of the dimensionality reduction method and classifier.
{"title":"Fiducial ECG-Based Biometry: Comparison of Classifiers and Dimensionality Reduction Methods","authors":"David Meltzer, D. Luengo","doi":"10.1109/TSP.2019.8768891","DOIUrl":"https://doi.org/10.1109/TSP.2019.8768891","url":null,"abstract":"Biometry is becoming increasingly important in order to identify or authenticate individuals. Since the seminar work of Biel et at. in 1999 and 2001, the feasibility of using the electrocardiogram (ECG) for biometric recognition has been considered by several authors. Both fiducial methods, which are based on using fiducial points related to the detected QRS complexes, and non-fiducial methods, which do not require the extraction of the QRS complexes from the signals, have been considered. However, the feasibility of ECG-based biometry is still unclear, as the results from different studies are difficult to compare. In this paper, we concentrate on fiducial methods, comparing the performance of several classifiers and dimensionality reduction techniques on a publicly available dataset. Our results show that ECG-based biometry is indeed a feasible alternative to other widely used biometric traits, since an accuracy above 99.95% can be attained with the appropriate choice of the dimensionality reduction method and classifier.","PeriodicalId":399087,"journal":{"name":"2019 42nd International Conference on Telecommunications and Signal Processing (TSP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123589818","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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