Pub Date : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573904
G. Andrade, L. Lima, A. Calsavara, J. D. Oliveira, G. Michelon
Delay/Disruption-Tolerant Networks (DTNs) have been used in many different scenarios and are characterized by the high mobility of nodes, the constant disconnection, the high delays for message delivery and the frequent partitioning. The union of Vehicular Ad hoc Networks (VANETs) and DTNs has created a new research field in Vehicular Delay-Tolerant Networks (VDTNs) based on DTN's stored-carry-and-forward mechanism and applying it to the vehicular context. This mechanism allows messages to be routed to their destinations without the need of end-to-end connections. Due to the widespread availability of low cost on-board communication devices, message routing in VDTN has become an important research target. That is why many protocols can be found in the literature with the goal of overcoming the challenges encountered by applications developed for this context. Nevertheless, these proposed protocols do not take into consideration important requirements such as: no dependency on Road Side Units (RSU) and mechanisms to obtain information about the location of vehicles. This paper proposes and describes a message routing algorithm based on consciousness and human behavior in order to address the main demands of the VDTN environment.
{"title":"Message routing in vehicular delay-tolerant networks based on human behavior","authors":"G. Andrade, L. Lima, A. Calsavara, J. D. Oliveira, G. Michelon","doi":"10.1109/CSNDSP.2016.7573904","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573904","url":null,"abstract":"Delay/Disruption-Tolerant Networks (DTNs) have been used in many different scenarios and are characterized by the high mobility of nodes, the constant disconnection, the high delays for message delivery and the frequent partitioning. The union of Vehicular Ad hoc Networks (VANETs) and DTNs has created a new research field in Vehicular Delay-Tolerant Networks (VDTNs) based on DTN's stored-carry-and-forward mechanism and applying it to the vehicular context. This mechanism allows messages to be routed to their destinations without the need of end-to-end connections. Due to the widespread availability of low cost on-board communication devices, message routing in VDTN has become an important research target. That is why many protocols can be found in the literature with the goal of overcoming the challenges encountered by applications developed for this context. Nevertheless, these proposed protocols do not take into consideration important requirements such as: no dependency on Road Side Units (RSU) and mechanisms to obtain information about the location of vehicles. This paper proposes and describes a message routing algorithm based on consciousness and human behavior in order to address the main demands of the VDTN environment.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122533839","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7574036
M. Najafi, G. Baghersalimi, Mohammad Reza Alizadeh, Mohamad Rahimi, A. Burton
In this paper the impact of a Radio-over-Fiber (RoF) optical subsystem on the sensitivity to the phase noise of Orthogonal Frequency Division Multiplexing (OFDM) in a multiple-input multiple-output (MIMO) system is evaluated and a method for reducing the effect of this phase noise is presented using computer simulation. The study investigates the effect of phase noise on the system Bit Error Rate (BER) for different Output-Back-Off levels in the presence of optical subsystem's nonlinearity in an AWGN channel. Hence, a way to reduce its effect is presented by estimating this phase offset that it is called synchronization of phase noise.
{"title":"Synchronization of a MIMO-OFDM based radio-over-fiber communication system in the presence of phase noise","authors":"M. Najafi, G. Baghersalimi, Mohammad Reza Alizadeh, Mohamad Rahimi, A. Burton","doi":"10.1109/CSNDSP.2016.7574036","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7574036","url":null,"abstract":"In this paper the impact of a Radio-over-Fiber (RoF) optical subsystem on the sensitivity to the phase noise of Orthogonal Frequency Division Multiplexing (OFDM) in a multiple-input multiple-output (MIMO) system is evaluated and a method for reducing the effect of this phase noise is presented using computer simulation. The study investigates the effect of phase noise on the system Bit Error Rate (BER) for different Output-Back-Off levels in the presence of optical subsystem's nonlinearity in an AWGN channel. Hence, a way to reduce its effect is presented by estimating this phase offset that it is called synchronization of phase noise.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126860368","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7574026
Aydin Kizilkaya, M. D. Elbi, Ali Kirkbas
The empirical mode decomposition (EMD) is a popular tool that is valid for nonlinear and nonstationary signal analysis. Applying this tool to any given signal reveals a finite set of oscillatory modes termed intrinsic mode functions (IMFs) and a residual. The sum of all extracted IMFs and the residual reconstructs the original signal without any information loss. Although the EMD satisfies the perfect reconstruction property, it is not based on any optimality criterion. This is an important issue especially in using the EMD for reconstructing the original signal from its noisy versions. At this point, a more flexible form of the EMD is required. Related to this issue, recently, only a few formulations are developed. In addition to these ones, in this paper, a new signal reconstruction algorithm termed time-varying weighted EMD is proposed. This algorithm is optimal in the least-squares error sense and tries to reconstruct the original signal by the sum of time-varying weighted IMFs and residual signal. It is demonstrated by simulations that the proposed algorithm introduces superior performance than that of the existing ones in reconstructing the desired signal after denoising.
{"title":"Least-squares error based optimal signal reconstruction using time-varying weighted empirical mode decomposition","authors":"Aydin Kizilkaya, M. D. Elbi, Ali Kirkbas","doi":"10.1109/CSNDSP.2016.7574026","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7574026","url":null,"abstract":"The empirical mode decomposition (EMD) is a popular tool that is valid for nonlinear and nonstationary signal analysis. Applying this tool to any given signal reveals a finite set of oscillatory modes termed intrinsic mode functions (IMFs) and a residual. The sum of all extracted IMFs and the residual reconstructs the original signal without any information loss. Although the EMD satisfies the perfect reconstruction property, it is not based on any optimality criterion. This is an important issue especially in using the EMD for reconstructing the original signal from its noisy versions. At this point, a more flexible form of the EMD is required. Related to this issue, recently, only a few formulations are developed. In addition to these ones, in this paper, a new signal reconstruction algorithm termed time-varying weighted EMD is proposed. This algorithm is optimal in the least-squares error sense and tries to reconstruct the original signal by the sum of time-varying weighted IMFs and residual signal. It is demonstrated by simulations that the proposed algorithm introduces superior performance than that of the existing ones in reconstructing the desired signal after denoising.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134491935","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573942
Andi Soekartono, Yu Chen, I. Darwazeh
We study two cross layer simulation models with different LTE MAC scheduler types in this paper: a discrete time simulation model and a discrete event simulation model. Results show that under similar settings, these two simulation models produce similar results in a single user scenario but perform differently in a multi-UE scenario. Moreover, the proportional fair scheduling is shown to be the fairest one using both simulation models.
{"title":"PHY-MAC cross layer based modelling for LTE QoS optimization","authors":"Andi Soekartono, Yu Chen, I. Darwazeh","doi":"10.1109/CSNDSP.2016.7573942","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573942","url":null,"abstract":"We study two cross layer simulation models with different LTE MAC scheduler types in this paper: a discrete time simulation model and a discrete event simulation model. Results show that under similar settings, these two simulation models produce similar results in a single user scenario but perform differently in a multi-UE scenario. Moreover, the proportional fair scheduling is shown to be the fairest one using both simulation models.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129215630","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7574011
S. Rakshit, M. Hempel, H. Sharif
Advances in Wireless Sensor Networks (WSN) have enabled new technologies to offer enriched reliability, seamless mobility, safety, and security in surface transportation. In rail transportation, WSNs play an important role in real-time monitoring of freight railcars to prevent major failures and derailments. However, the wireless communications among a large number of sensors onboard of a train present unique challenges due to the linear rail network topology, wireless signal interference from locomotives and railcars, and limited power sources available on freight railcars. In this presentation, we discuss a unique two-layer WSN architecture suitable for freight railroads.
{"title":"Wireless sensor networks in surface transportation","authors":"S. Rakshit, M. Hempel, H. Sharif","doi":"10.1109/CSNDSP.2016.7574011","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7574011","url":null,"abstract":"Advances in Wireless Sensor Networks (WSN) have enabled new technologies to offer enriched reliability, seamless mobility, safety, and security in surface transportation. In rail transportation, WSNs play an important role in real-time monitoring of freight railcars to prevent major failures and derailments. However, the wireless communications among a large number of sensors onboard of a train present unique challenges due to the linear rail network topology, wireless signal interference from locomotives and railcars, and limited power sources available on freight railcars. In this presentation, we discuss a unique two-layer WSN architecture suitable for freight railroads.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114172135","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573910
I. Moscholios, V. Vassilakis, M. Logothetis
In this paper, we study the performance of the Multiple Fractional Channel Reservation (MFCR) policy, which is a bandwidth reservation policy that allows the reservation of real (not integer) number of channels in order to favor calls of high channel (bandwidth) requirements. We consider a link of fixed capacity that accommodates Poisson arriving calls of different service-classes with different bandwidth-per-call requirements. Calls compete for the available bandwidth under the MFCR policy. To determine call blocking probabilities, we propose approximate but recursive formulas based on the notion of reserve transition rates. The accuracy of the proposed method is verified through simulation.
{"title":"Call blocking probabilities for poisson traffic under the multiple fractional channel reservation policy","authors":"I. Moscholios, V. Vassilakis, M. Logothetis","doi":"10.1109/CSNDSP.2016.7573910","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573910","url":null,"abstract":"In this paper, we study the performance of the Multiple Fractional Channel Reservation (MFCR) policy, which is a bandwidth reservation policy that allows the reservation of real (not integer) number of channels in order to favor calls of high channel (bandwidth) requirements. We consider a link of fixed capacity that accommodates Poisson arriving calls of different service-classes with different bandwidth-per-call requirements. Calls compete for the available bandwidth under the MFCR policy. To determine call blocking probabilities, we propose approximate but recursive formulas based on the notion of reserve transition rates. The accuracy of the proposed method is verified through simulation.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129677517","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7574030
F. Sheikhshoaei, M. Asadi, S. Sadeghi, A. Mahani
Energy efficient routing algorithm is an important issue in WSNs applications. In this paper we propose an ant colony algorithm based on smell factor, SUMACO, for delay-constraint multicast routing applications. Simulation results verify the speed of proposed algorithm to find the final tree of multicast routing. In Comparison with the conventional ant colony algorithm, the convergence speed and also the cost of SUMACO is strongly improved.
{"title":"Low cost ACA-based multicast routing for multi-media applications","authors":"F. Sheikhshoaei, M. Asadi, S. Sadeghi, A. Mahani","doi":"10.1109/CSNDSP.2016.7574030","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7574030","url":null,"abstract":"Energy efficient routing algorithm is an important issue in WSNs applications. In this paper we propose an ant colony algorithm based on smell factor, SUMACO, for delay-constraint multicast routing applications. Simulation results verify the speed of proposed algorithm to find the final tree of multicast routing. In Comparison with the conventional ant colony algorithm, the convergence speed and also the cost of SUMACO is strongly improved.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131823445","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573955
S. Olyaee, A. Nikoosohbat, Ahmad Mohebzadeh Bahabady, Ata Chizari
Photonic crystal fibers (PCFs) are widely used in optical communications systems, nonlinear devices, gas sensors, high power transmission, and so on. Photonic crystal fiber with minimum values of confinement loss, nonlinear effects, and chromatic dispersion is used in optical communication. But in some applications, high nonlinear coefficient is required. This paper presents new design of index-guiding photonic crystal fiber (IGPCF) with characteristics appropriate for nonlinear applications. In the present design with a square-hexagonal nano-structure having air holes with unequal diameters, nearly zero dispersion at the wavelength range of 1540 to 1550 nm is achieved. The simulation results reveal that the slope of chromatic dispersion is obtained as -0.05 ps/(km.nm). The confinement loss is less than 10-12 dB/cm and the nonlinear coefficient reaches 8.380 W-1.km-1.
{"title":"Square-hexagonal nanostructured photonic crystal fiber at 1550 nm wavelength","authors":"S. Olyaee, A. Nikoosohbat, Ahmad Mohebzadeh Bahabady, Ata Chizari","doi":"10.1109/CSNDSP.2016.7573955","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573955","url":null,"abstract":"Photonic crystal fibers (PCFs) are widely used in optical communications systems, nonlinear devices, gas sensors, high power transmission, and so on. Photonic crystal fiber with minimum values of confinement loss, nonlinear effects, and chromatic dispersion is used in optical communication. But in some applications, high nonlinear coefficient is required. This paper presents new design of index-guiding photonic crystal fiber (IGPCF) with characteristics appropriate for nonlinear applications. In the present design with a square-hexagonal nano-structure having air holes with unequal diameters, nearly zero dispersion at the wavelength range of 1540 to 1550 nm is achieved. The simulation results reveal that the slope of chromatic dispersion is obtained as -0.05 ps/(km.nm). The confinement loss is less than 10-12 dB/cm and the nonlinear coefficient reaches 8.380 W-1.km-1.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131730139","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573927
Kai-Daniel Buchter
Large-scale airborne communication networks are modeled, using a simulation of global, wide-body aircraft movements and assuming the use of optical communication links. Statistics concerning the expected node degree as function of communication range and ratios of connected aircraft are presented. It is found that, with an ambitious but plausible communication range of 450 km, on average 80% of world-wide, oceanic flights may connect to ground gateways via airborne networking in the simulation.
{"title":"Availability of airborne Ad-hoc communication network in global air traffic simulation","authors":"Kai-Daniel Buchter","doi":"10.1109/CSNDSP.2016.7573927","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573927","url":null,"abstract":"Large-scale airborne communication networks are modeled, using a simulation of global, wide-body aircraft movements and assuming the use of optical communication links. Statistics concerning the expected node degree as function of communication range and ratios of connected aircraft are presented. It is found that, with an ambitious but plausible communication range of 450 km, on average 80% of world-wide, oceanic flights may connect to ground gateways via airborne networking in the simulation.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133477911","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 : 2016-07-20DOI: 10.1109/CSNDSP.2016.7573974
R. Martínek, R. Kahankova, H. Skutová, P. Koudelka, J. Zidek, J. Koziorek
The extraction of the Fetal Electrocardiogram (fECG) from the composite Electrocardiogram (ECG) signal obtained from the abdominal lead is discussed. The main point of this paper is to introduce some of the most used Least Mean Squares (LMS) based Finite Impulse Response (FIR) Adaptive Filters and to determine which of them are the most effective under varying circumstances. Experimental results suggest the ideal combination of the chosen settings for these functions. Results of fECG extraction are assessed by Percentage Root-Mean-Square Difference (PRD), input and output Signal to Noise Ratios (SNRs), and Root Mean Square Error (RMSE). Based on simulations conclusions, optimal convergence constant value and filter order were empirically determined. Setting the optimal value of the convergence constant and filter order of adaptive algorithm can be considered a contribution to original results. These results can be used on real records fECG, where it is difficult to determine because of the missing reference.
{"title":"Adaptive signal processing techniques for extracting abdominal fetal electrocardiogram","authors":"R. Martínek, R. Kahankova, H. Skutová, P. Koudelka, J. Zidek, J. Koziorek","doi":"10.1109/CSNDSP.2016.7573974","DOIUrl":"https://doi.org/10.1109/CSNDSP.2016.7573974","url":null,"abstract":"The extraction of the Fetal Electrocardiogram (fECG) from the composite Electrocardiogram (ECG) signal obtained from the abdominal lead is discussed. The main point of this paper is to introduce some of the most used Least Mean Squares (LMS) based Finite Impulse Response (FIR) Adaptive Filters and to determine which of them are the most effective under varying circumstances. Experimental results suggest the ideal combination of the chosen settings for these functions. Results of fECG extraction are assessed by Percentage Root-Mean-Square Difference (PRD), input and output Signal to Noise Ratios (SNRs), and Root Mean Square Error (RMSE). Based on simulations conclusions, optimal convergence constant value and filter order were empirically determined. Setting the optimal value of the convergence constant and filter order of adaptive algorithm can be considered a contribution to original results. These results can be used on real records fECG, where it is difficult to determine because of the missing reference.","PeriodicalId":298711,"journal":{"name":"2016 10th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134588571","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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