Pub Date : 2013-03-20DOI: 10.1109/CISS.2013.6552334
J. Ojaniemi, Juha Kalliovaara, A. Alam, J. Poikonen, R. Wichman
White spaces are locally or temporally available frequencies that are principally reserved for primary use such as TV broadcasting. The currently prevalent view to the utilization of such spectrum resources is that white space devices must query a geolocation database to obtain information about available frequencies and related maximum transmission powers. A geolocation database is fundamentally based on field strength estimates of the primary service obtained using radio propagation models. However, field strength estimates for geographically extensive broadcast networks are typically computed for spatial resolutions of hundreds of square meters. Therefore, even with the most sophisticated propagation models currently available, the predicted values always contain errors due to the limited geographical information. To overcome such deficiency, we propose a geostatistical approach for estimating the radio environment based on universal kriging interpolation. In addition, we optimize the locations of field measurements using spatial simulated annealing, and show that it improves significantly local field strength estimates. Index Terms-radio
{"title":"Optimal field measurement design for radio environment mapping","authors":"J. Ojaniemi, Juha Kalliovaara, A. Alam, J. Poikonen, R. Wichman","doi":"10.1109/CISS.2013.6552334","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552334","url":null,"abstract":"White spaces are locally or temporally available frequencies that are principally reserved for primary use such as TV broadcasting. The currently prevalent view to the utilization of such spectrum resources is that white space devices must query a geolocation database to obtain information about available frequencies and related maximum transmission powers. A geolocation database is fundamentally based on field strength estimates of the primary service obtained using radio propagation models. However, field strength estimates for geographically extensive broadcast networks are typically computed for spatial resolutions of hundreds of square meters. Therefore, even with the most sophisticated propagation models currently available, the predicted values always contain errors due to the limited geographical information. To overcome such deficiency, we propose a geostatistical approach for estimating the radio environment based on universal kriging interpolation. In addition, we optimize the locations of field measurements using spatial simulated annealing, and show that it improves significantly local field strength estimates. Index Terms-radio","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130984254","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552339
Shunqiao Sun, A. Petropulu
Beamforming methods rely on training data to estimate the covariance matrix of the interference pulse noise. Their convergence slows down if the signal of interest is present in the training data, thus requiring a large numbers of training snapshots to maintain good performance. In a distributed array, in which the array nodes are connected to a fusion center via a wireless link, the estimation of the covariance matrix would require the communication of large amounts of data, and thus would consume significant power. We propose an approach that enables good beamforming performance while requiring substantially fewer data to be transmitted to the fusion center. The main idea is based on the fact that when the number of signal and interference sources is much smaller than the number of array sensors, the training data matrix is low rank. Thus, based on matrix completion theory, under certain conditions, the training data matrix can be recovered from a subset of its elements, i.e., based on sub-Nyquist samples of the array sensors. Following the recovery of the training data matrix, and to cope with the errors introduced during the matrix completion process, we propose a robust optimization approach, which obtains the beamforming weight vector by optimizing the worst-case performance. Numerical results show that combination of matrix completion and robust optimization is very successful in suppressing interference and achieving a near-optimal beamforming performance with only partial training data.
{"title":"Robust beamforming via matrix completion","authors":"Shunqiao Sun, A. Petropulu","doi":"10.1109/CISS.2013.6552339","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552339","url":null,"abstract":"Beamforming methods rely on training data to estimate the covariance matrix of the interference pulse noise. Their convergence slows down if the signal of interest is present in the training data, thus requiring a large numbers of training snapshots to maintain good performance. In a distributed array, in which the array nodes are connected to a fusion center via a wireless link, the estimation of the covariance matrix would require the communication of large amounts of data, and thus would consume significant power. We propose an approach that enables good beamforming performance while requiring substantially fewer data to be transmitted to the fusion center. The main idea is based on the fact that when the number of signal and interference sources is much smaller than the number of array sensors, the training data matrix is low rank. Thus, based on matrix completion theory, under certain conditions, the training data matrix can be recovered from a subset of its elements, i.e., based on sub-Nyquist samples of the array sensors. Following the recovery of the training data matrix, and to cope with the errors introduced during the matrix completion process, we propose a robust optimization approach, which obtains the beamforming weight vector by optimizing the worst-case performance. Numerical results show that combination of matrix completion and robust optimization is very successful in suppressing interference and achieving a near-optimal beamforming performance with only partial training data.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131109274","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552324
Xu Chen, P. Ramadge
An effective music genre classication approach is proposed that combines the translation-invariance and deformation-robustness property of scattering coefficients and the discriminative power of sparse representation-based classifiers. We argue that these two approaches to feature selection and classification complement each other in reducing the in-class variability of data, and this should lead to enhanced performance. Our results show clear improvement over a variety of previous approaches. A music genre classication accuracy of approximately 91.2% on the GTZAN database is reported.
{"title":"Music genre classification using multiscale scattering and sparse representations","authors":"Xu Chen, P. Ramadge","doi":"10.1109/CISS.2013.6552324","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552324","url":null,"abstract":"An effective music genre classication approach is proposed that combines the translation-invariance and deformation-robustness property of scattering coefficients and the discriminative power of sparse representation-based classifiers. We argue that these two approaches to feature selection and classification complement each other in reducing the in-class variability of data, and this should lead to enhanced performance. Our results show clear improvement over a variety of previous approaches. A music genre classication accuracy of approximately 91.2% on the GTZAN database is reported.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133650775","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552337
T. Riihonen, Mikko Vehkaperä, R. Wichman
We analyze the performance of bidirectional communication links between two multi-antenna full-duplex transceivers, explicitly taking into account the effect of unavoidable self-interference. The main theme of this paper is to compare spatial-domain suppression (implemented in the form of null-space projection) and subtractive time-domain cancellation: both schemes can eliminate the self-interference but the former consumes spatial degrees of freedom unlike the latter. We perform large-system analysis based on the replica method, while reference simulations show that the asymptotic results are applicable also for practical systems with low number of antennas. In particular, we evaluate rate regions achieved by controlling the spatial multiplexing order in each node and time sharing between different stream configurations. Consequently, we can characterize the rate loss of suppression versus cancellation.
{"title":"Large-system analysis of rate regions in bidirectional full-duplex MIMO link: Suppression versus cancellation","authors":"T. Riihonen, Mikko Vehkaperä, R. Wichman","doi":"10.1109/CISS.2013.6552337","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552337","url":null,"abstract":"We analyze the performance of bidirectional communication links between two multi-antenna full-duplex transceivers, explicitly taking into account the effect of unavoidable self-interference. The main theme of this paper is to compare spatial-domain suppression (implemented in the form of null-space projection) and subtractive time-domain cancellation: both schemes can eliminate the self-interference but the former consumes spatial degrees of freedom unlike the latter. We perform large-system analysis based on the replica method, while reference simulations show that the asymptotic results are applicable also for practical systems with low number of antennas. In particular, we evaluate rate regions achieved by controlling the spatial multiplexing order in each node and time sharing between different stream configurations. Consequently, we can characterize the rate loss of suppression versus cancellation.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132043324","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552321
T. Duong, D. Nguyen-Huu, Thinh P. Q. Nguyen
Markov Decision Process (MDP) is a well-known framework for devising the optimal decision making strategies under uncertainty. Typically, the decision maker assumes a stationary environment which is characterized by a time-invariant transition probability matrix. However, in many realworld scenarios, this assumption is not justified, thus the optimal strategy might not provide the expected performance. In this paper, we study the performance of the classic Value Iteration (VI) algorithm for solving an MDP problem under non-stationary environments. Specifically, the non-stationary environment is modeled as a sequence of time-variant transition probability matrices governed by an adiabatic evolution inspired from quantum mechanics. We characterize the performance of the VI algorithm subject to the rate of change of the underlying environment. The performance is measured in terms of the convergence rate to the optimal average reward. We show two examples of queuing systems that make use of our analysis framework.
{"title":"Adiabatic Markov Decision Process with application to queuing systems","authors":"T. Duong, D. Nguyen-Huu, Thinh P. Q. Nguyen","doi":"10.1109/CISS.2013.6552321","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552321","url":null,"abstract":"Markov Decision Process (MDP) is a well-known framework for devising the optimal decision making strategies under uncertainty. Typically, the decision maker assumes a stationary environment which is characterized by a time-invariant transition probability matrix. However, in many realworld scenarios, this assumption is not justified, thus the optimal strategy might not provide the expected performance. In this paper, we study the performance of the classic Value Iteration (VI) algorithm for solving an MDP problem under non-stationary environments. Specifically, the non-stationary environment is modeled as a sequence of time-variant transition probability matrices governed by an adiabatic evolution inspired from quantum mechanics. We characterize the performance of the VI algorithm subject to the rate of change of the underlying environment. The performance is measured in terms of the convergence rate to the optimal average reward. We show two examples of queuing systems that make use of our analysis framework.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132626917","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 : 2013-03-20DOI: 10.1109/CISS.2013.6624265
S. Feizi, Amy Zhang, M. Médard
In this paper, by using network flow principles, we propose algorithms to address various challenges in cloud computing. One of the main challenges is to consider both communication and computation constraints in the network. In the proposed network flow framework, we model the amount of computation in each node of the network as a function of its total self-loop flows. We consider two computation cost models: a linear computation cost model and a maximum computation cost model. We show that, our network flow framework can be used as a systematic technique of balancing computation loads over different nodes of the network. This network flow framework can also be used for cloud network design. A network topology is optimal for certain computations if it maximizes the total computation rate under communication/computation constraints. We propose a greedy algorithm to design a cloud network with a certain network characteristics in terms of communication and computation costs. We provide simulation results to illustrate the performance of our algorithms.
{"title":"A Network Flow Approach in Cloud Computing","authors":"S. Feizi, Amy Zhang, M. Médard","doi":"10.1109/CISS.2013.6624265","DOIUrl":"https://doi.org/10.1109/CISS.2013.6624265","url":null,"abstract":"In this paper, by using network flow principles, we propose algorithms to address various challenges in cloud computing. One of the main challenges is to consider both communication and computation constraints in the network. In the proposed network flow framework, we model the amount of computation in each node of the network as a function of its total self-loop flows. We consider two computation cost models: a linear computation cost model and a maximum computation cost model. We show that, our network flow framework can be used as a systematic technique of balancing computation loads over different nodes of the network. This network flow framework can also be used for cloud network design. A network topology is optimal for certain computations if it maximizes the total computation rate under communication/computation constraints. We propose a greedy algorithm to design a cloud network with a certain network characteristics in terms of communication and computation costs. We provide simulation results to illustrate the performance of our algorithms.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133907653","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552282
Ali Iskurt, Y. Becerikli, K. Mahmutyazicioglu
While visualizing three dimensional (3D) structure of the coronary arteries, the projectory X-ray images can produce 3D tree of them up to a certain accuracy level with a lower dose of radiation when compared to computer tomography (CT). Here, in this study a novel and complete automatic system is designed which covers preprocessing, segmentation, matching and reconstruction steps for that purpose. First an automatic and novel pattern recognition technique is applied for the extraction of the bifurcation points with their diameters recorded in a map. Then, a novel optimization algorithm is run for matching the branches based on that map and the epipolar geometry of stereopsis. Finally, cut branches are fixed one by one at the bifurcations for completing the 3D reconstruction. The method favors the similar ones in the literature with this novelty since it inherently prevents the wrong overlapping of branches. Other essential problems like correct detection of bifurcation, detection of the true calibration parameters and fast overlapping of matched branches are addressed at acceptable levels. The precision of bifurcation extraction is high at 97% with 96% sensitivity. Accuracy of the vessel centerlines has root-mean-square (rms) error smaller than 0.5 mm for 10 different patients. For phantom model, rms error is 0.75 ± 0.8 mm in 3D localization.
{"title":"A fast and automatic calibration of the projectory images for 3D reconstruction of the branchy structures","authors":"Ali Iskurt, Y. Becerikli, K. Mahmutyazicioglu","doi":"10.1109/CISS.2013.6552282","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552282","url":null,"abstract":"While visualizing three dimensional (3D) structure of the coronary arteries, the projectory X-ray images can produce 3D tree of them up to a certain accuracy level with a lower dose of radiation when compared to computer tomography (CT). Here, in this study a novel and complete automatic system is designed which covers preprocessing, segmentation, matching and reconstruction steps for that purpose. First an automatic and novel pattern recognition technique is applied for the extraction of the bifurcation points with their diameters recorded in a map. Then, a novel optimization algorithm is run for matching the branches based on that map and the epipolar geometry of stereopsis. Finally, cut branches are fixed one by one at the bifurcations for completing the 3D reconstruction. The method favors the similar ones in the literature with this novelty since it inherently prevents the wrong overlapping of branches. Other essential problems like correct detection of bifurcation, detection of the true calibration parameters and fast overlapping of matched branches are addressed at acceptable levels. The precision of bifurcation extraction is high at 97% with 96% sensitivity. Accuracy of the vessel centerlines has root-mean-square (rms) error smaller than 0.5 mm for 10 different patients. For phantom model, rms error is 0.75 ± 0.8 mm in 3D localization.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134525505","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 : 2013-03-20DOI: 10.1109/CISS.2013.6624259
F. Moazzami, R. Dean, Yacob Astatke
In this work the problem of spectrum efficiency in wireless networks over aeronautical channels is studied and a solution by combining direct communications (LOS) and cooperative networking is proposed. In aeronautical communications due to large scale communication paths and sudden changes in the channel topology, extra measures needs to be taken to accommodate reliable and continuous communication for the flying articles. High ground speed of the mobile nodes is also another factor which needs to be accounted for in the network design. The proposed network management technique is dynamic in all senses and ensures connectivity at any given time.
{"title":"Use of K-means clustering for spectrum efficiency in complex networks","authors":"F. Moazzami, R. Dean, Yacob Astatke","doi":"10.1109/CISS.2013.6624259","DOIUrl":"https://doi.org/10.1109/CISS.2013.6624259","url":null,"abstract":"In this work the problem of spectrum efficiency in wireless networks over aeronautical channels is studied and a solution by combining direct communications (LOS) and cooperative networking is proposed. In aeronautical communications due to large scale communication paths and sudden changes in the channel topology, extra measures needs to be taken to accommodate reliable and continuous communication for the flying articles. High ground speed of the mobile nodes is also another factor which needs to be accounted for in the network design. The proposed network management technique is dynamic in all senses and ensures connectivity at any given time.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116645166","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552302
Liang Chen
The capacity of relay channels has been an open problem for decades. Decode-and-forward (DAF) and compress-and-forward (CAF) are two strategies to obtain lower bounds to the capacity. They have been well studied for the discrete SISO case. However, for the Gaussian case, we have had the limited results. The optimal input distribution to achieve the maximum rate derived from the discrete case has been known only for the DAF scheme, but not for the CAF scheme. Furthermore, the results are difficult to extend to the MIMO case. In this paper, we study the achievable rates of the Gaussian MIMO relay channels. We derive the achievable rates for both DAF and CAF relaying.
{"title":"On achievable rates for Gaussian MIMO relay channels","authors":"Liang Chen","doi":"10.1109/CISS.2013.6552302","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552302","url":null,"abstract":"The capacity of relay channels has been an open problem for decades. Decode-and-forward (DAF) and compress-and-forward (CAF) are two strategies to obtain lower bounds to the capacity. They have been well studied for the discrete SISO case. However, for the Gaussian case, we have had the limited results. The optimal input distribution to achieve the maximum rate derived from the discrete case has been known only for the DAF scheme, but not for the CAF scheme. Furthermore, the results are difficult to extend to the MIMO case. In this paper, we study the achievable rates of the Gaussian MIMO relay channels. We derive the achievable rates for both DAF and CAF relaying.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123486332","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 : 2013-03-20DOI: 10.1109/CISS.2013.6552267
Shuya Dong, Jungwoo Lee
In this paper, we deal with Bayesian restless multi-armed bandit (RMAB) techniques which are appliced to Cognitive Radio. We assume there are multiple arms, each of which evolves as a Markov chain with known parameters. A player seeks to activate more than one arms at each time in order to maximize the expected total reward with multiple plays. We consider non-Bayesian RMAB where the parameters of the Markov chain are unknown. We propose a simple but effective algorithm called two-slot greedy confidence bound algorithm (Two-slot GCB), which perform better than existing upper confidence bound (UCB) algorithms.
{"title":"Greedy confidence bound techniques for restless multi-armed bandit based Cognitive Radio","authors":"Shuya Dong, Jungwoo Lee","doi":"10.1109/CISS.2013.6552267","DOIUrl":"https://doi.org/10.1109/CISS.2013.6552267","url":null,"abstract":"In this paper, we deal with Bayesian restless multi-armed bandit (RMAB) techniques which are appliced to Cognitive Radio. We assume there are multiple arms, each of which evolves as a Markov chain with known parameters. A player seeks to activate more than one arms at each time in order to maximize the expected total reward with multiple plays. We consider non-Bayesian RMAB where the parameters of the Markov chain are unknown. We propose a simple but effective algorithm called two-slot greedy confidence bound algorithm (Two-slot GCB), which perform better than existing upper confidence bound (UCB) algorithms.","PeriodicalId":268095,"journal":{"name":"2013 47th Annual Conference on Information Sciences and Systems (CISS)","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124716471","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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