Pub Date : 2009-06-14DOI: 10.1109/ICCW.2009.5207964
A. González Prieto, D. Dudkowski, C. Meirosu, C. Mingardi, G. Nunzi, M. Brunner, R. Stadler
In-network management (INM) is a new paradigm for the management of the future Internet that is based on the principles of decentralization and self-organization. Its goal is to overcome the limitations of traditional network management and to achieve scalable and robust management systems with low complexity for large-scale, dynamic network environments. In this paper, we describe a framework for INM that provides a systematic approach to the embedding of management algorithms within the elements of a communication networks. In addition, we demonstrate the benefits of decentralized management in the context of two key management functions, namely real-time monitoring and event handling.
{"title":"Decentralized In-Network Management for the Future Internet","authors":"A. González Prieto, D. Dudkowski, C. Meirosu, C. Mingardi, G. Nunzi, M. Brunner, R. Stadler","doi":"10.1109/ICCW.2009.5207964","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5207964","url":null,"abstract":"In-network management (INM) is a new paradigm for the management of the future Internet that is based on the principles of decentralization and self-organization. Its goal is to overcome the limitations of traditional network management and to achieve scalable and robust management systems with low complexity for large-scale, dynamic network environments. In this paper, we describe a framework for INM that provides a systematic approach to the embedding of management algorithms within the elements of a communication networks. In addition, we demonstrate the benefits of decentralized management in the context of two key management functions, namely real-time monitoring and event handling.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123699825","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5208032
K. Arshad, K. Moessner
Today’s wireless communication systems follow fixed spectrum assignment policies which leads to overall inefficient spectrum use. Further, spectrum scarcity is an issue for operators with emerging mobile services and large number of users with even higher capacity requirements. This inefficiency and scarcity in spectrum usage necessitates a new paradigm for communications such as utilising available spectrum opportunistically. Cognitive Radio (CR) is an enabling technology having potential to increase spectrum utilisation and provide desired interference protection to licenced users. This can be done by detection of spectrum opportunities by secondary users. Due to channel fading and shadowing a single user can not make a reliable decision and collaboration of and among users is required. In this paper, it has been demonstrated that for improved detection performance decision fusion algorithm for collaborative spectrum sensing must have information about channel and the mean SNR of all secondary users. Using Monte Carlo simulations it is concluded that for optimum performance it is not necessary that all users collaborate with each other.
{"title":"Collaborative Spectrum Sensing for Cognitive Radio","authors":"K. Arshad, K. Moessner","doi":"10.1109/ICCW.2009.5208032","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5208032","url":null,"abstract":"Today’s wireless communication systems follow fixed spectrum assignment policies which leads to overall inefficient spectrum use. Further, spectrum scarcity is an issue for operators with emerging mobile services and large number of users with even higher capacity requirements. This inefficiency and scarcity in spectrum usage necessitates a new paradigm for communications such as utilising available spectrum opportunistically. Cognitive Radio (CR) is an enabling technology having potential to increase spectrum utilisation and provide desired interference protection to licenced users. This can be done by detection of spectrum opportunities by secondary users. Due to channel fading and shadowing a single user can not make a reliable decision and collaboration of and among users is required. In this paper, it has been demonstrated that for improved detection performance decision fusion algorithm for collaborative spectrum sensing must have information about channel and the mean SNR of all secondary users. Using Monte Carlo simulations it is concluded that for optimum performance it is not necessary that all users collaborate with each other.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114735103","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5208081
H. Hellbruck, H. Xin, M. Lipphardt
Today new medical applications evolve from large stationary devices to small and smart mobile systems that will enable e.g. more efficient post operative health care. These mobile systems that benefit from ongoing miniaturization and energy savings in hardware will allow continuous monitoring of patients accompanying and supporting therapy and detect emergency situations. Additionally to vital data, the physiological load or the context of patients are important to analyze and understand recorded data of mobile patients. Current approaches for movement classification aim to detect very specific movement patterns and are dependent on precise sensor placements and are thus not suited for everyday usage. Therefore, we developed a movement detection and classification algorithm that can be easily integrated in existing embedded devices. Using data from a single accelerometer embedded into the device, the algorithm can classify between different movement patterns - the "context" - of the monitored person. We will describe the hardware and the algorithm and will provide first evaluation results demonstrating the effectiveness of this approach for providing context awareness in mobile medical applications in real-time.
{"title":"Effective Movement Classification for Context Awareness in Medical Applications Networking","authors":"H. Hellbruck, H. Xin, M. Lipphardt","doi":"10.1109/ICCW.2009.5208081","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5208081","url":null,"abstract":"Today new medical applications evolve from large stationary devices to small and smart mobile systems that will enable e.g. more efficient post operative health care. These mobile systems that benefit from ongoing miniaturization and energy savings in hardware will allow continuous monitoring of patients accompanying and supporting therapy and detect emergency situations. Additionally to vital data, the physiological load or the context of patients are important to analyze and understand recorded data of mobile patients. Current approaches for movement classification aim to detect very specific movement patterns and are dependent on precise sensor placements and are thus not suited for everyday usage. Therefore, we developed a movement detection and classification algorithm that can be easily integrated in existing embedded devices. Using data from a single accelerometer embedded into the device, the algorithm can classify between different movement patterns - the \"context\" - of the monitored person. We will describe the hardware and the algorithm and will provide first evaluation results demonstrating the effectiveness of this approach for providing context awareness in mobile medical applications in real-time.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129386130","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5207983
C. Mensing, S. Sand, A. Dammann
In critical situations (e.g., urban canyons) for global navigation satellite systems (GNSSs) only less than the required four satellites can be accessed, and hence, just a limited positioning performance can be achieved. This paper covers the improvement of GNSS based positioning in these critical scenarios by hybrid data fusion (HDF) algorithms using additional measurements from a communications system. Moreover, this HDF is integrated in a tracking algorithm which exploits an extended Kalman filter (EKF) for further performance improvement. Simulation results show the ability of this approach to compensate the lack of satellites by additional timing measurements from a future 3GPP-LTE communications system. Contrary to state-of-the-art work, this paper analyzes the performance in a fairly realistic manner especially by taking into account raytracing simulations to obtain a coherent environment.
{"title":"GNSS Positioning in Critical Scenarios: Hybrid Data Fusion with Communications Signals","authors":"C. Mensing, S. Sand, A. Dammann","doi":"10.1109/ICCW.2009.5207983","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5207983","url":null,"abstract":"In critical situations (e.g., urban canyons) for global navigation satellite systems (GNSSs) only less than the required four satellites can be accessed, and hence, just a limited positioning performance can be achieved. This paper covers the improvement of GNSS based positioning in these critical scenarios by hybrid data fusion (HDF) algorithms using additional measurements from a communications system. Moreover, this HDF is integrated in a tracking algorithm which exploits an extended Kalman filter (EKF) for further performance improvement. Simulation results show the ability of this approach to compensate the lack of satellites by additional timing measurements from a future 3GPP-LTE communications system. Contrary to state-of-the-art work, this paper analyzes the performance in a fairly realistic manner especially by taking into account raytracing simulations to obtain a coherent environment.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130846653","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5207982
Christian Dannewitz
The Internet contains a lot of information that can be very useful to support users in real-world activities and while on the go. Unfortunately, this information is currently very cumbersome to access and accessing the information disrupts the users' workflow. Internet services that offer those information with a seamless real-world integration are missing. In this paper, we argue that such Internet services are currently difficult to develop on a large scale because conceptual support for such applications is missing. Therefore, we propose a new paradigm, the Augmented Internet, that integrates a conceptual connection between the Internet and the real world into the next generation Internet. Requirements for the next generation Internet are analyzed based on multiple use cases. From this analysis, we conclude that it is feasible and advantageous to implement real- world integration as integral part of an information-centric network approach. To enable this, future information-centric network research has to take some additional requirements into consideration, resulting in minor but critical changes to the information-centric network approach, as will be discussed in this paper. I. INTRODUCTION
{"title":"Augmented Internet: An Information-Centric Approach for Real-World / Internet Integration","authors":"Christian Dannewitz","doi":"10.1109/ICCW.2009.5207982","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5207982","url":null,"abstract":"The Internet contains a lot of information that can be very useful to support users in real-world activities and while on the go. Unfortunately, this information is currently very cumbersome to access and accessing the information disrupts the users' workflow. Internet services that offer those information with a seamless real-world integration are missing. In this paper, we argue that such Internet services are currently difficult to develop on a large scale because conceptual support for such applications is missing. Therefore, we propose a new paradigm, the Augmented Internet, that integrates a conceptual connection between the Internet and the real world into the next generation Internet. Requirements for the next generation Internet are analyzed based on multiple use cases. From this analysis, we conclude that it is feasible and advantageous to implement real- world integration as integral part of an information-centric network approach. To enable this, future information-centric network research has to take some additional requirements into consideration, resulting in minor but critical changes to the information-centric network approach, as will be discussed in this paper. I. INTRODUCTION","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129552459","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5208024
S. Brueck, J. Giese, L. Zhao, A. Dekorsy
Coordinated transmission between base stations is one of the techniques under investigation to further improve the system performance of E-UTRA. In general, such a coordination, sometimes also called network MIMO, requires a large amount of signaling between cells. A relatively simple scheme for cell coordination is macro diversity. In this paper we consider macro diversity for the downlink direction of LTE-Advanced as a means to improve cell edge user throughput. We investigate the frequency-selectivity gains offered by over the air combining for different radio channels at link level. The impact on cell throughput as well as on user throughput for mobiles operated in macro diversity mode and for legacy mobile stations is investigated by means of system level simulations. Additionally, open issues related to network coordination are identified for future work.
{"title":"On MAC Layer Throughput Enhancements in LTE-A by Downlink Macro Diversity","authors":"S. Brueck, J. Giese, L. Zhao, A. Dekorsy","doi":"10.1109/ICCW.2009.5208024","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5208024","url":null,"abstract":"Coordinated transmission between base stations is one of the techniques under investigation to further improve the system performance of E-UTRA. In general, such a coordination, sometimes also called network MIMO, requires a large amount of signaling between cells. A relatively simple scheme for cell coordination is macro diversity. In this paper we consider macro diversity for the downlink direction of LTE-Advanced as a means to improve cell edge user throughput. We investigate the frequency-selectivity gains offered by over the air combining for different radio channels at link level. The impact on cell throughput as well as on user throughput for mobiles operated in macro diversity mode and for legacy mobile stations is investigated by means of system level simulations. Additionally, open issues related to network coordination are identified for future work.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117096969","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5207984
C. Fritsche, A. Klein
The Global Positioning System (GPS) has become one of the state-of-the-art location systems that offers reliable mobile terminal (MT) location estimates. However, there exist situations where GPS is not available, e.g., when the MT is used indoors or when the MT is located close to high buildings. In these scenarios, a promising approach is to combine the GPS measured values with measured values from the Global System for Mobile Communication (GSM), which is known as hybrid localization method. In this paper, a hybrid MT tracking algorithm based on a Rao-Blackwellized unscented Kalman filter (RBUKF) is proposed that combines pseudoranges from GPS with timing advance and received signal strengths from GSM. Simulation results show that the proposed hybrid method outperforms the GSM method. Furthermore, the performance of the RBUKF is compared to the extended Kalman filter and the corresponding posterior Cramer-Rao lower bounds.
{"title":"On the Performance of Hybrid GPS/GSM Mobile Terminal Tracking","authors":"C. Fritsche, A. Klein","doi":"10.1109/ICCW.2009.5207984","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5207984","url":null,"abstract":"The Global Positioning System (GPS) has become one of the state-of-the-art location systems that offers reliable mobile terminal (MT) location estimates. However, there exist situations where GPS is not available, e.g., when the MT is used indoors or when the MT is located close to high buildings. In these scenarios, a promising approach is to combine the GPS measured values with measured values from the Global System for Mobile Communication (GSM), which is known as hybrid localization method. In this paper, a hybrid MT tracking algorithm based on a Rao-Blackwellized unscented Kalman filter (RBUKF) is proposed that combines pseudoranges from GPS with timing advance and received signal strengths from GSM. Simulation results show that the proposed hybrid method outperforms the GSM method. Furthermore, the performance of the RBUKF is compared to the extended Kalman filter and the corresponding posterior Cramer-Rao lower bounds.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126000275","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5208001
B. Timus, J. Zander
High capacity mobile broadband access requires a dense infrastructure of base stations. The costs associated with the backhaul transmission for these base stations is often a significant part of the total cost of the access network. It has been proposed to use part of the available spectrum to route data between base stations, so-called in-band relaying or self-backhauling. Although self-backhauling may result in a lower total system capacity, we will in this paper show examples where temporary use of in-band relaying postpones investments in fixed backhaul connections. This reduces the total (life-time) cost of the access network. In our incremental strategy example the total cost savings are in the order of 5 to 10%, depending on the relation between the additional equipment cost and the cost of leasing the fixed backhaul. Self-backhauling is not worth implementing when the entire network capacity needs to be achieved up-front, but the savings are significant when service uptake is slow or difficult to predict. The discount rate used in the investment analysis has only a minor impact on the results.
{"title":"Incremental Deployment with Self-Backhauling Base Stations in Urban Environment","authors":"B. Timus, J. Zander","doi":"10.1109/ICCW.2009.5208001","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5208001","url":null,"abstract":"High capacity mobile broadband access requires a dense infrastructure of base stations. The costs associated with the backhaul transmission for these base stations is often a significant part of the total cost of the access network. It has been proposed to use part of the available spectrum to route data between base stations, so-called in-band relaying or self-backhauling. Although self-backhauling may result in a lower total system capacity, we will in this paper show examples where temporary use of in-band relaying postpones investments in fixed backhaul connections. This reduces the total (life-time) cost of the access network. In our incremental strategy example the total cost savings are in the order of 5 to 10%, depending on the relation between the additional equipment cost and the cost of leasing the fixed backhaul. Self-backhauling is not worth implementing when the entire network capacity needs to be achieved up-front, but the savings are significant when service uptake is slow or difficult to predict. The discount rate used in the investment analysis has only a minor impact on the results.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126765370","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5207971
Jimmy Kjällman
In this paper we examine how network attachment can be handled in a system where all communication, both on a data link and in a network, is based on the publish/subscribe paradigm instead of the traditional send/receive model. We present and discuss an early clean-slate solution to the problem of establishing and maintaining network connectivity between nodes in a secure and efficient way. The solution includes a basic protocol for pub/sub-based attachment, which addresses certain pertinent security challenges and conforms with the principle of receiver-driven communication. In addition, we report initial experiences from implementing the concepts outlined in our protocol design.
{"title":"Attachment to a Native Publish/Subscribe Network","authors":"Jimmy Kjällman","doi":"10.1109/ICCW.2009.5207971","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5207971","url":null,"abstract":"In this paper we examine how network attachment can be handled in a system where all communication, both on a data link and in a network, is based on the publish/subscribe paradigm instead of the traditional send/receive model. We present and discuss an early clean-slate solution to the problem of establishing and maintaining network connectivity between nodes in a secure and efficient way. The solution includes a basic protocol for pub/sub-based attachment, which addresses certain pertinent security challenges and conforms with the principle of receiver-driven communication. In addition, we report initial experiences from implementing the concepts outlined in our protocol design.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129157332","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 : 2009-06-14DOI: 10.1109/ICCW.2009.5208073
F. Librino, M. Levorato, Marco Zorzi
In this paper we address the deployment of cooper- ation in a cellular CDMA environment. In particular, we consider the use of Amplify and Forward to increase the maximum number of users that can be assigned to each base station. In our scenario, a certain number of fixed Relay Stations are positioned within the cell: each of them is assigned a group of Mobile Terminals, whose transmissions are received and retransmitted towards the Base Station. We study the rule for the assignment of Mobile Terminals to the fixed Relay Stations placed in the cell and we investigate the transmission power required by each user in order to reach a given average Signal to Interference plus Noise Ratio (SINR) level. We present numerical results quantifying the increased capability of a cell to accommodate users granted by cooperation in terms of coverage range and dropping probability.
{"title":"Performance Analysis and Resource Allocation in CDMA Cellular Networks with Relay Stations","authors":"F. Librino, M. Levorato, Marco Zorzi","doi":"10.1109/ICCW.2009.5208073","DOIUrl":"https://doi.org/10.1109/ICCW.2009.5208073","url":null,"abstract":"In this paper we address the deployment of cooper- ation in a cellular CDMA environment. In particular, we consider the use of Amplify and Forward to increase the maximum number of users that can be assigned to each base station. In our scenario, a certain number of fixed Relay Stations are positioned within the cell: each of them is assigned a group of Mobile Terminals, whose transmissions are received and retransmitted towards the Base Station. We study the rule for the assignment of Mobile Terminals to the fixed Relay Stations placed in the cell and we investigate the transmission power required by each user in order to reach a given average Signal to Interference plus Noise Ratio (SINR) level. We present numerical results quantifying the increased capability of a cell to accommodate users granted by cooperation in terms of coverage range and dropping probability.","PeriodicalId":271067,"journal":{"name":"2009 IEEE International Conference on Communications Workshops","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123985257","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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