Pub Date : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105127
A. Fedeli, M. Pastorino, A. Randazzo
This paper reports the results of the application of a microwave imaging method developed in Banach spaces to a model of human head in presence of a hemorrhagic brain stroke. The approach is based on the integral equations of the inverse scattering problem. A Gauss-Newton scheme is adopted as a solving procedure. Being developed in Banach spaces, the method turns out to be quite efficient in reducing the over-smoothing effects usually associated to Hilbert-space reconstructions. Numerical simulations are reported involving a realistic model of human head.
{"title":"Electromagnetic biomedical imaging in Banach spaces: A numerical case study","authors":"A. Fedeli, M. Pastorino, A. Randazzo","doi":"10.23919/URSIGASS.2017.8105127","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105127","url":null,"abstract":"This paper reports the results of the application of a microwave imaging method developed in Banach spaces to a model of human head in presence of a hemorrhagic brain stroke. The approach is based on the integral equations of the inverse scattering problem. A Gauss-Newton scheme is adopted as a solving procedure. Being developed in Banach spaces, the method turns out to be quite efficient in reducing the over-smoothing effects usually associated to Hilbert-space reconstructions. Numerical simulations are reported involving a realistic model of human head.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126751676","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105305
M. Koroglu, O. Koroglu, F. Arıkan
Ground Based Augmentation Systems (GBAS) monitor the ionosphere locally for giving measurement integrity information to nearby users. Monitoring systems use ionospheric threat models to calculate the integrity information and contain ionospheric gradients estimated from the ionospheric slant delays through the maximum gradient observed days. These models show only maximum gradient estimates according to the elevation angles of the satellites. In this study, ionospheric gradients are analyzed seasonally in order to give input information to the threat modeling process over Turkey. In the analysis process, developed method also shows the effects of the geomagnetic storms and earthquakes on the ionospheric gradients. As a result, for the first time, by using the developed tool, a detailed seasonal threat modeling is obtained over Turkey for year 2011. According to the analysis results, maximum gradient observed as 20 mm/km and variability of the gradients are highly dependent on to geomagnetic storms and earthquakes over Turkey in 2011. The seasons with more earthquakes and geomagnetic storms have more high gradients.
{"title":"Analysis of seasonal ionospheric gradients over Turkey for year 2011","authors":"M. Koroglu, O. Koroglu, F. Arıkan","doi":"10.23919/URSIGASS.2017.8105305","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105305","url":null,"abstract":"Ground Based Augmentation Systems (GBAS) monitor the ionosphere locally for giving measurement integrity information to nearby users. Monitoring systems use ionospheric threat models to calculate the integrity information and contain ionospheric gradients estimated from the ionospheric slant delays through the maximum gradient observed days. These models show only maximum gradient estimates according to the elevation angles of the satellites. In this study, ionospheric gradients are analyzed seasonally in order to give input information to the threat modeling process over Turkey. In the analysis process, developed method also shows the effects of the geomagnetic storms and earthquakes on the ionospheric gradients. As a result, for the first time, by using the developed tool, a detailed seasonal threat modeling is obtained over Turkey for year 2011. According to the analysis results, maximum gradient observed as 20 mm/km and variability of the gradients are highly dependent on to geomagnetic storms and earthquakes over Turkey in 2011. The seasons with more earthquakes and geomagnetic storms have more high gradients.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115087518","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105374
Z. Zaw, V. P. Bui, C. Png
Tasks to be carried out in maritime are usually expensive due to the use of the manned vessels with large operational crews that includes the safety of life and property at sea environment. Utilization of drones has potential to significantly improve the efficiency and safety of marine and offshore operations. Examples include remotely operated inspection for navigation, surveillance or monitoring ship conditions including emissions, unmanned offshore delivery from shore and search & rescue operations. With defining of new technology as marine drones in such applications, ensuring robust control under harsh offshore environments is the critical issue that needs to be addressed before marine drones can be adopted for widespread commercial use. One of the key research areas to ensure the robust control and operation of marine drones is wireless communication link between drone and control station [1]. The main radio-wave propagation mechanism for near sea-surface applications in an evaporation duct is illustrated in Figure 1.
{"title":"Efficient wireless link modeling for marine drone application under harsh offshore environment","authors":"Z. Zaw, V. P. Bui, C. Png","doi":"10.23919/URSIGASS.2017.8105374","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105374","url":null,"abstract":"Tasks to be carried out in maritime are usually expensive due to the use of the manned vessels with large operational crews that includes the safety of life and property at sea environment. Utilization of drones has potential to significantly improve the efficiency and safety of marine and offshore operations. Examples include remotely operated inspection for navigation, surveillance or monitoring ship conditions including emissions, unmanned offshore delivery from shore and search & rescue operations. With defining of new technology as marine drones in such applications, ensuring robust control under harsh offshore environments is the critical issue that needs to be addressed before marine drones can be adopted for widespread commercial use. One of the key research areas to ensure the robust control and operation of marine drones is wireless communication link between drone and control station [1]. The main radio-wave propagation mechanism for near sea-surface applications in an evaporation duct is illustrated in Figure 1.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122450509","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105027
O. Demir, G. Dural
In this study, an analytical method is proposed for the derivation of radiation characteristics of spherical-rectangular printed antenna arrays without suffering from rectangular grid alignment. The far-field solutions obtained by the spherical cavity model are transformed with respect to the geometrical locations of each rectangular antenna on the conducting sphere. The transformations are realized by using the spherical vector rotation techniques. Then, the superposition of far-field solutions is implemented to obtain the total far-field pattern and the result is compared with pattern of the antenna array that conforms to the rectangular grid alignment.
{"title":"Cavity model analysis of spherical-rectangular printed antennas by employing basic spherical vector transformation techniques","authors":"O. Demir, G. Dural","doi":"10.23919/URSIGASS.2017.8105027","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105027","url":null,"abstract":"In this study, an analytical method is proposed for the derivation of radiation characteristics of spherical-rectangular printed antenna arrays without suffering from rectangular grid alignment. The far-field solutions obtained by the spherical cavity model are transformed with respect to the geometrical locations of each rectangular antenna on the conducting sphere. The transformations are realized by using the spherical vector rotation techniques. Then, the superposition of far-field solutions is implemented to obtain the total far-field pattern and the result is compared with pattern of the antenna array that conforms to the rectangular grid alignment.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122494792","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105296
S. Phang, G. Gradoni, A. Vukovic, S. Creagh, T. Benson
The established time domain Transmission-Line Modelling (TLM) numerical method is extended to include models of (i) saturable dispersive gain and (ii) non-linear dielectric material. The method is used to simulate a photonic memory device based on a nonlinear Parity-Time (PT) structure.
{"title":"Transmission-line model for a non-linear and dispersive parity-time (PT) symmetric structure","authors":"S. Phang, G. Gradoni, A. Vukovic, S. Creagh, T. Benson","doi":"10.23919/URSIGASS.2017.8105296","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105296","url":null,"abstract":"The established time domain Transmission-Line Modelling (TLM) numerical method is extended to include models of (i) saturable dispersive gain and (ii) non-linear dielectric material. The method is used to simulate a photonic memory device based on a nonlinear Parity-Time (PT) structure.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122806673","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}
Uniformity of root-mean-square delay spread (RMS-DS) is important for the reliability of over-the-air test when reverberation chamber (RC) is used as a wireless channel simulator. Both the state of stirrers and location of devices under test could affect the uniformity of RMS-DS. In this study we measured the RMS-DS in RC when stirrers were in different state and receiving antenna was located at different positions in the test volume, and the uniformity of RMS-DS was evaluated by standard divisions. Our results showed that the standard division of RMS-DS arising from the states of stirrers was 30 ns to 50 ns, from the locations of receiving antenna was 17 ns to 33 ns, and the holistic standard division was 41 ns to 52 ns. Comparing with the mean value of RMS-DS simulated in RC, which is 3.1 μs to 3.8 μs, the uniformity is in the level of 1% and mainly caused by states of stirrers. In sum, our study introduced the first example of experimental investigation on the uniformity of RMS-DS simulated in RC.
{"title":"Experimental investigation of the uniformity of root-mean-square delay spread simulated in reverberation chamber","authors":"Xiaotao Guo, Zhao He, Yichi Zhang, Lifeng Wang, Xin Zhou","doi":"10.23919/URSIGASS.2017.8105351","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105351","url":null,"abstract":"Uniformity of root-mean-square delay spread (RMS-DS) is important for the reliability of over-the-air test when reverberation chamber (RC) is used as a wireless channel simulator. Both the state of stirrers and location of devices under test could affect the uniformity of RMS-DS. In this study we measured the RMS-DS in RC when stirrers were in different state and receiving antenna was located at different positions in the test volume, and the uniformity of RMS-DS was evaluated by standard divisions. Our results showed that the standard division of RMS-DS arising from the states of stirrers was 30 ns to 50 ns, from the locations of receiving antenna was 17 ns to 33 ns, and the holistic standard division was 41 ns to 52 ns. Comparing with the mean value of RMS-DS simulated in RC, which is 3.1 μs to 3.8 μs, the uniformity is in the level of 1% and mainly caused by states of stirrers. In sum, our study introduced the first example of experimental investigation on the uniformity of RMS-DS simulated in RC.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"385 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122819820","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}
In this paper, we investigate the propagation coupling loss (captures all sources of attenuation between serving cell and mobile station (MS)) and geometry metric (GM) (downlink average signal-to-interference plus noise ratio) performance of mmWave cellular networks for outdoor and indoor MSs, considering urban micro (UMi) environments. Based on these studies, we identify effective mmWave frequency bands for cellular communication. We consider 3GPP compliant system-level simulations with two power allocation schemes: 1) transmit power scaled with communication bandwidth, and 2) constant total transmit power. Simulation results show that with scaled transmit power allocation, GM performance degradation is small: 20% of MSs experience GM less than 0 dB at all mmWave frequencies considered, for outdoor MSs. With constant Tx power allocation, 20% of MSs experience GM less than 0 dB for frequencies up to 30 GHz. Furthermore, 35% (48%) of outdoor MSs experience GM performance less than 0 dB at 60 GHz (100 GHz). On the other hand, for indoor MSs, even with scaled Tx power allocation, favorable GM performance is observed only at low frequencies, i.e., 2 GHz.
{"title":"System-level performance of mmWave cellular networks for urban micro environments","authors":"Nadisanka Rupasinghe, Yuichi Kakishima, Ismail Güvenç","doi":"10.23919/URSIGASS.2017.8105388","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105388","url":null,"abstract":"In this paper, we investigate the propagation coupling loss (captures all sources of attenuation between serving cell and mobile station (MS)) and geometry metric (GM) (downlink average signal-to-interference plus noise ratio) performance of mmWave cellular networks for outdoor and indoor MSs, considering urban micro (UMi) environments. Based on these studies, we identify effective mmWave frequency bands for cellular communication. We consider 3GPP compliant system-level simulations with two power allocation schemes: 1) transmit power scaled with communication bandwidth, and 2) constant total transmit power. Simulation results show that with scaled transmit power allocation, GM performance degradation is small: 20% of MSs experience GM less than 0 dB at all mmWave frequencies considered, for outdoor MSs. With constant Tx power allocation, 20% of MSs experience GM less than 0 dB for frequencies up to 30 GHz. Furthermore, 35% (48%) of outdoor MSs experience GM performance less than 0 dB at 60 GHz (100 GHz). On the other hand, for indoor MSs, even with scaled Tx power allocation, favorable GM performance is observed only at low frequencies, i.e., 2 GHz.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114417317","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105262
Caiyun Wang, Shuxia Wu, Zhiyong He
A new multi-feature fusion method is proposed for the radar target recognition based on D-S evidence iterative discount method. Firstly, the discount factor is defined based on the multi-feature confusion matrix and basic probability assignment (BPA) function. Then, when the conflict is high, the evidence is discounted using the discount factor, and basic probability assignment function, discount factor and conflict coefficient are updated; repeat the above discounts procedure and stop the evidence source correction when the evidence conflict coefficient is less than the threshold. Finally, fusion recognition is achieved by using the revised evidence. Compared with the other fusion recognition algorithm, the simulation results show that this proposed algorithm performs better.
{"title":"Multi-feature fusion for target recognition based on improved D-S evidence iterative discount method","authors":"Caiyun Wang, Shuxia Wu, Zhiyong He","doi":"10.23919/URSIGASS.2017.8105262","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105262","url":null,"abstract":"A new multi-feature fusion method is proposed for the radar target recognition based on D-S evidence iterative discount method. Firstly, the discount factor is defined based on the multi-feature confusion matrix and basic probability assignment (BPA) function. Then, when the conflict is high, the evidence is discounted using the discount factor, and basic probability assignment function, discount factor and conflict coefficient are updated; repeat the above discounts procedure and stop the evidence source correction when the evidence conflict coefficient is less than the threshold. Finally, fusion recognition is achieved by using the revised evidence. Compared with the other fusion recognition algorithm, the simulation results show that this proposed algorithm performs better.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121980140","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105094
D. Matolak, Ruoyu Sun
Based upon recent results from an air-ground channel measurement campaign, we investigate relationships between three common channel parameters: Ricean K-factor, stationarity distance (SD), and root-mean square delay spread (RMS-DS). Results show that SD and K are positively correlated, SD and dK/dt are negatively correlated, and SD and the temporal derivative of RMS-DS are also negatively correlated.
{"title":"Relationships among statistical channel parameters for an air-ground channel: Stationarity distance, ricean K-factor, and RMS delay spread","authors":"D. Matolak, Ruoyu Sun","doi":"10.23919/URSIGASS.2017.8105094","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105094","url":null,"abstract":"Based upon recent results from an air-ground channel measurement campaign, we investigate relationships between three common channel parameters: Ricean K-factor, stationarity distance (SD), and root-mean square delay spread (RMS-DS). Results show that SD and K are positively correlated, SD and dK/dt are negatively correlated, and SD and the temporal derivative of RMS-DS are also negatively correlated.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"233 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122068904","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 : 2017-08-01DOI: 10.23919/URSIGASS.2017.8105267
S. Creagh, J. Blackburn, G. Gradoni, T. Hartmann, S. Phang, G. Tanner
Emissions from modern electronic circuitry are inherently complex and necessarily statistically characterized. The goal in this work is to characterise such emissions as they operate in a realistic environment. When the surrounding environment is electromagnetically large, or complex, the problem of simulating such emissions is further compounded by the intractability of full EM wave modeling: at high enough frequencies, approximate methods based on ray tracing may be the only feasible approach. In this paper, we present a statistical description of fluctuations in the high-frequency response of complex or ray-chaotic cavities to such stochastic sources. It is based on a method proposed in [1], which exploits information available as a byproduct of ray-tracing simulations to predict in addition to the averaged intensity that is typically obtained directly from ray tracing, higher moments which characterize fluctuations about the mean response. This paper extends that approach to provide full statistical distributions of the intensity when damping is moderate and under assumptions that multiple reflections in the surrounding environment are sufficiently randomizing.
{"title":"Statistics of fluctuation in the response of cavities excited by noisy sources","authors":"S. Creagh, J. Blackburn, G. Gradoni, T. Hartmann, S. Phang, G. Tanner","doi":"10.23919/URSIGASS.2017.8105267","DOIUrl":"https://doi.org/10.23919/URSIGASS.2017.8105267","url":null,"abstract":"Emissions from modern electronic circuitry are inherently complex and necessarily statistically characterized. The goal in this work is to characterise such emissions as they operate in a realistic environment. When the surrounding environment is electromagnetically large, or complex, the problem of simulating such emissions is further compounded by the intractability of full EM wave modeling: at high enough frequencies, approximate methods based on ray tracing may be the only feasible approach. In this paper, we present a statistical description of fluctuations in the high-frequency response of complex or ray-chaotic cavities to such stochastic sources. It is based on a method proposed in [1], which exploits information available as a byproduct of ray-tracing simulations to predict in addition to the averaged intensity that is typically obtained directly from ray tracing, higher moments which characterize fluctuations about the mean response. This paper extends that approach to provide full statistical distributions of the intensity when damping is moderate and under assumptions that multiple reflections in the surrounding environment are sufficiently randomizing.","PeriodicalId":377869,"journal":{"name":"2017 XXXIInd General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129618675","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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