Pub Date : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245853
M. Ohta, T. Fujii, K. Muraoka, M. Ariyoshi
This paper proposes a novel power controlled sensing information gathering for cooperative sensing on shared spectrum with primary system while jointly using individual sensing results at each node. We apply simultaneous sensing information gathering by using an orthogonal frequency signal. This method can keep the interference power to the primary receiver low. Simulation results show that the power controlled cooperative sensing can obtain good sensing performance without harmful interference toward the primary system.
{"title":"A novel power controlled sensing information gathering for cooperative sensing on shared spectrum with primary spectrum","authors":"M. Ohta, T. Fujii, K. Muraoka, M. Ariyoshi","doi":"10.4108/ICST.CROWNCOM.2011.245853","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245853","url":null,"abstract":"This paper proposes a novel power controlled sensing information gathering for cooperative sensing on shared spectrum with primary system while jointly using individual sensing results at each node. We apply simultaneous sensing information gathering by using an orthogonal frequency signal. This method can keep the interference power to the primary receiver low. Simulation results show that the power controlled cooperative sensing can obtain good sensing performance without harmful interference toward the primary system.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116865256","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245896
M. Kucharzak, Jacek Kibiłda, Marcin Filo, R. Piesiewicz
In this paper we propose and examine 802.11b-based MAC protocol for wireless ad-hoc relay networks. The objective of the proposed protocol is to incorporate self-enforcing strategy to achieve energy efficiency in function of joules required for providing data transmission between end users. Regarding energy requirements for transmitting and receiving frames, it is desirable for every node in a wireless system, to get access to the channel as fast as possible and occupy it for a reasonably short period. The protocol design addresses the relay's self-selection mechanism which is based on internal motivation. The motivation refers to willingness of candidate relay to aid the ongoing transmission with regard to possibility of being awarded faster access to wireless medium, yielding decrease in energy consumption spent in waiting mode. The paper reports major improvements in terms of energy efficiency for most of the presented scenarios, while using relaying protocol in contrast to non-relaying 802.11b.
{"title":"Self-enforcement strategy for energy-efficient relaying in wireless ad-hoc networks","authors":"M. Kucharzak, Jacek Kibiłda, Marcin Filo, R. Piesiewicz","doi":"10.4108/ICST.CROWNCOM.2011.245896","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245896","url":null,"abstract":"In this paper we propose and examine 802.11b-based MAC protocol for wireless ad-hoc relay networks. The objective of the proposed protocol is to incorporate self-enforcing strategy to achieve energy efficiency in function of joules required for providing data transmission between end users. Regarding energy requirements for transmitting and receiving frames, it is desirable for every node in a wireless system, to get access to the channel as fast as possible and occupy it for a reasonably short period. The protocol design addresses the relay's self-selection mechanism which is based on internal motivation. The motivation refers to willingness of candidate relay to aid the ongoing transmission with regard to possibility of being awarded faster access to wireless medium, yielding decrease in energy consumption spent in waiting mode. The paper reports major improvements in terms of energy efficiency for most of the presented scenarios, while using relaying protocol in contrast to non-relaying 802.11b.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"171 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129397029","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245904
Tian Tian, H. Iwai, H. Sasaoka
In order to avoid interference to primary users within cognitive radio, a multi-frequency RTS/CTS scheme is studied in this paper. Assuming that channels suffer from Rayleigh fading and shadowing, we derive a closed-form of interference avoidance criterion based on multi-frequency RTS/CTS scheme. Simulations are carried out to validate the theoretical formulation. Results show that with the interference avoidance criterion based on the multi-frequency RTS/CTS scheme, interference can be rationally avoided. Propagation impacts on the criterion are also discussed and the analysis indicates that the required transmit power of the primary receiver is affected heavily by propagation characteristics.
{"title":"Statistical analysis of interference avoidance based on multi-frequency RTS/CTS cognitive radio","authors":"Tian Tian, H. Iwai, H. Sasaoka","doi":"10.4108/ICST.CROWNCOM.2011.245904","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245904","url":null,"abstract":"In order to avoid interference to primary users within cognitive radio, a multi-frequency RTS/CTS scheme is studied in this paper. Assuming that channels suffer from Rayleigh fading and shadowing, we derive a closed-form of interference avoidance criterion based on multi-frequency RTS/CTS scheme. Simulations are carried out to validate the theoretical formulation. Results show that with the interference avoidance criterion based on the multi-frequency RTS/CTS scheme, interference can be rationally avoided. Propagation impacts on the criterion are also discussed and the analysis indicates that the required transmit power of the primary receiver is affected heavily by propagation characteristics.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132557074","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245906
Francisco Novillo, R. Ferrús
A promising approach to alleviate ISM band congestion problems in highly dense WLAN scenarios consists of exploiting opportunistic spectrum access (OSA) to underutilized bands under a primary-secondary model. This paper develops a distributed channel assignment algorithm valid for uncoordinated WLAN deployments where access points do not follow any specific planning and they could belong to different administrative domains. Unlike existing channel assignment schemes proposed for legacy WLANs, channel assignment mechanisms for OSA-enabled WLAN should address two distinguishing issues: channel prioritization and spectrum heterogeneity. Over such a basis, this paper develops and assesses the performance of a distributed channel assignment algorithm that is able to exploit both channel prioritization and spectrum heterogeneity concepts. In particular, the algorithm is based on a distributed adaptation of the simulated annealing metaheuristic algorithm commonly used in global optimization problems.
{"title":"Distributed channel assignment algorithm based on simulated annealing for uncoordinated OSA-enabled WLANs","authors":"Francisco Novillo, R. Ferrús","doi":"10.4108/ICST.CROWNCOM.2011.245906","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245906","url":null,"abstract":"A promising approach to alleviate ISM band congestion problems in highly dense WLAN scenarios consists of exploiting opportunistic spectrum access (OSA) to underutilized bands under a primary-secondary model. This paper develops a distributed channel assignment algorithm valid for uncoordinated WLAN deployments where access points do not follow any specific planning and they could belong to different administrative domains. Unlike existing channel assignment schemes proposed for legacy WLANs, channel assignment mechanisms for OSA-enabled WLAN should address two distinguishing issues: channel prioritization and spectrum heterogeneity. Over such a basis, this paper develops and assesses the performance of a distributed channel assignment algorithm that is able to exploit both channel prioritization and spectrum heterogeneity concepts. In particular, the algorithm is based on a distributed adaptation of the simulated annealing metaheuristic algorithm commonly used in global optimization problems.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132772223","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245763
Jonathan S. Lu, I. Lu
This paper proposes a novel propagation based spectrum sensing method that utilizes beamforming for systems equipped with antenna arrays. Since rays are known to arrive in clusters, the arrival angles of the dominant ray clusters can be exploited to improve the spectral sensing performances. Moreover, from site-specific propagation characteristics, the dominant ray angles can be predicted without additional computational efforts in most practical environments. Numerical results based on ray-based channel models show that the proposed beamforming detection method (with or without dominant ray angle prediction) is superior to the conventional energy detection method. Numerical results also show that decreasing the angle spread, enhances the performance of the proposed method. The computational complexity and latency of the proposed method is the same as the conventional energy detection method when using dominant ray angle prediction, but increases slightly without prediction.
{"title":"Propagation based spectrum sensing: A novel beamforming detection method","authors":"Jonathan S. Lu, I. Lu","doi":"10.4108/ICST.CROWNCOM.2011.245763","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245763","url":null,"abstract":"This paper proposes a novel propagation based spectrum sensing method that utilizes beamforming for systems equipped with antenna arrays. Since rays are known to arrive in clusters, the arrival angles of the dominant ray clusters can be exploited to improve the spectral sensing performances. Moreover, from site-specific propagation characteristics, the dominant ray angles can be predicted without additional computational efforts in most practical environments. Numerical results based on ray-based channel models show that the proposed beamforming detection method (with or without dominant ray angle prediction) is superior to the conventional energy detection method. Numerical results also show that decreasing the angle spread, enhances the performance of the proposed method. The computational complexity and latency of the proposed method is the same as the conventional energy detection method when using dominant ray angle prediction, but increases slightly without prediction.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133506062","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245846
Guido Dartmann, Xitao Gong, G. Ascheid
This paper presents a low complexity sub-optimal algorithm for the max-min beamforming problem in multicell multicast transmission. The beam pattern is jointly optimized for all users inside a cell in a multicell scenario such that the signal to interference plus noise ratio (SINR) of the worst users is maximized subject to a limited sum power. The presented algorithm is based on the Lagrangian dual problem of the downlink max-min beamforming problem. The SINR of the presented algorithm is very close to the SINR of the known solution based on the more complex semidefinite programming.
{"title":"Low complexity cooperative multicast beamforming in multiuser multicell downlink networks","authors":"Guido Dartmann, Xitao Gong, G. Ascheid","doi":"10.4108/ICST.CROWNCOM.2011.245846","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245846","url":null,"abstract":"This paper presents a low complexity sub-optimal algorithm for the max-min beamforming problem in multicell multicast transmission. The beam pattern is jointly optimized for all users inside a cell in a multicell scenario such that the signal to interference plus noise ratio (SINR) of the worst users is maximized subject to a limited sum power. The presented algorithm is based on the Lagrangian dual problem of the downlink max-min beamforming problem. The SINR of the presented algorithm is very close to the SINR of the known solution based on the more complex semidefinite programming.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"348 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115463719","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.246000
Alireza Louni, B. Khalaj
In this paper, we propose a power control algorithm incorporating distributed beam-forming via multi-relay structure with underlay cognitive radio architecture. This problem is modeled as a non-cooperative game and a novel distributed algorithm is designed to achieve Nash equilibrium (NE). At each iteration, power and beam forming weights are determined while quality of service (QoS) of primary and secondary users are guaranteed in terms of interference threshold and signal to interference and noise (SINR) threshold levels, respectively. Convergence of the proposed algorithm to a unique and sub-optimal fixed point for any given initial resource allocation has been proved. Numerical simulations demonstrate significant improvement in average rate of secondary users in comparison with single-relay algorithms.
{"title":"Distributed beam-forming and power control in multi-relay underlay cognitive radio networks: A game-theoretical approach","authors":"Alireza Louni, B. Khalaj","doi":"10.4108/ICST.CROWNCOM.2011.246000","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.246000","url":null,"abstract":"In this paper, we propose a power control algorithm incorporating distributed beam-forming via multi-relay structure with underlay cognitive radio architecture. This problem is modeled as a non-cooperative game and a novel distributed algorithm is designed to achieve Nash equilibrium (NE). At each iteration, power and beam forming weights are determined while quality of service (QoS) of primary and secondary users are guaranteed in terms of interference threshold and signal to interference and noise (SINR) threshold levels, respectively. Convergence of the proposed algorithm to a unique and sub-optimal fixed point for any given initial resource allocation has been proved. Numerical simulations demonstrate significant improvement in average rate of secondary users in comparison with single-relay algorithms.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115483704","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.246139
H. Harada, M. Oodo, R. Funada, Mingtuo Zhou, Liru Lu, Xin Zhang
This paper presents research status on public broadband wireless communication (PBB) system. The PBB system uses VHF band between 170 MHz and 205 MHz that is available after termination of analogue TV broadcasting service on July 24, 2011. This paper summarizes the transition of television service from analogue to digital and fundamental specification on spectrum usage, physical and MAC layers.
{"title":"A public broadband wireless communication system on VHF TV band","authors":"H. Harada, M. Oodo, R. Funada, Mingtuo Zhou, Liru Lu, Xin Zhang","doi":"10.4108/ICST.CROWNCOM.2011.246139","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.246139","url":null,"abstract":"This paper presents research status on public broadband wireless communication (PBB) system. The PBB system uses VHF band between 170 MHz and 205 MHz that is available after termination of analogue TV broadcasting service on July 24, 2011. This paper summarizes the transition of television service from analogue to digital and fundamental specification on spectrum usage, physical and MAC layers.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121323830","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245908
Takanori Sato, M. Umehira
A periodogram scheme, a multi-taper scheme, and a filter-bank scheme are proposed for spectrum sensing for dynamic spectrum access. The filter-bank scheme is advantageous in hardware implementation since the hardware required for communications can be reused for spectrum sensing. However, it is difficult for the conventional filter-bank scheme to change the detection bandwidth, filter type and frequency channel since the conventional filter-bank is based on time domain signal processing. This paper proposes a new spectrum sensing scheme using overlap FFT filter-bank based on frequency domain signal processing, which can flexibly change the detection bandwidth, filter type and frequency channel. In addition, this paper proposes a windowing method to improve the false-detection performance and confirms its improvement by computer simulation. Furthermore, false-detection and miss-detection performance of the proposed spectrum sensing scheme are evaluated and compared with those of the periodogram scheme according to the roll-off factor of the filter and modulation scheme.
{"title":"A new spectrum sensing scheme using overlap FFT filter-bank for dynamic spectrum access","authors":"Takanori Sato, M. Umehira","doi":"10.4108/ICST.CROWNCOM.2011.245908","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245908","url":null,"abstract":"A periodogram scheme, a multi-taper scheme, and a filter-bank scheme are proposed for spectrum sensing for dynamic spectrum access. The filter-bank scheme is advantageous in hardware implementation since the hardware required for communications can be reused for spectrum sensing. However, it is difficult for the conventional filter-bank scheme to change the detection bandwidth, filter type and frequency channel since the conventional filter-bank is based on time domain signal processing. This paper proposes a new spectrum sensing scheme using overlap FFT filter-bank based on frequency domain signal processing, which can flexibly change the detection bandwidth, filter type and frequency channel. In addition, this paper proposes a windowing method to improve the false-detection performance and confirms its improvement by computer simulation. Furthermore, false-detection and miss-detection performance of the proposed spectrum sensing scheme are evaluated and compared with those of the periodogram scheme according to the roll-off factor of the filter and modulation scheme.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123343615","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 : 2011-06-01DOI: 10.4108/ICST.CROWNCOM.2011.245826
Yinglin Xu, Z. Feng, Ping Zhang
Cognitive Wireless Network (CWN), which is a set of heterogeneity networks with the capability of perceiving, planning, deciding and learning according to current multi-domain environment and end-to-end goals, is motivated by the integration, ubiquity and broadband requirements of future networks. But the rising complexity of heterogeneity networks and the need to manage this complexity make the actualization of CWN timely and attractive. Many related projects are built for research teams to do further study. We are undertaking a project called “Basic theory and Key Technologies in Cognitive Wireless Networks” which is one of the major projects in National Basic Research Program (973 Program) approved by the Chinese government. Our research team focuses on issues from network architecture to multi-dimension sensing technologies and radio resource management which are related to each other. In this article, an overview of this project is given by discussing its purpose, research vision, research progress, and testbed.
{"title":"Research on Cognitive Wireless Networks: Theory, Key Technologies and testbed","authors":"Yinglin Xu, Z. Feng, Ping Zhang","doi":"10.4108/ICST.CROWNCOM.2011.245826","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2011.245826","url":null,"abstract":"Cognitive Wireless Network (CWN), which is a set of heterogeneity networks with the capability of perceiving, planning, deciding and learning according to current multi-domain environment and end-to-end goals, is motivated by the integration, ubiquity and broadband requirements of future networks. But the rising complexity of heterogeneity networks and the need to manage this complexity make the actualization of CWN timely and attractive. Many related projects are built for research teams to do further study. We are undertaking a project called “Basic theory and Key Technologies in Cognitive Wireless Networks” which is one of the major projects in National Basic Research Program (973 Program) approved by the Chinese government. Our research team focuses on issues from network architecture to multi-dimension sensing technologies and radio resource management which are related to each other. In this article, an overview of this project is given by discussing its purpose, research vision, research progress, and testbed.","PeriodicalId":249175,"journal":{"name":"2011 6th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125296249","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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