Pub Date : 2014-10-23DOI: 10.1109/ISWCS.2014.6933428
Alfonso Martinez, J. Scarlett, M. Dalai, A. G. Fàbregas
This paper derives a saddlepoint approximation for the random-coding bound to the error probability of channel coding by using complex-integration techniques. The approximation is given by a sum of two terms: one with Gallager's exponent, and a second one with Arimoto's strong converse exponent (above capacity) or the sphere-packing exponent (below the critical rate).
{"title":"A complex-integration approach to the saddlepoint approximation for random-coding bounds","authors":"Alfonso Martinez, J. Scarlett, M. Dalai, A. G. Fàbregas","doi":"10.1109/ISWCS.2014.6933428","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933428","url":null,"abstract":"This paper derives a saddlepoint approximation for the random-coding bound to the error probability of channel coding by using complex-integration techniques. The approximation is given by a sum of two terms: one with Gallager's exponent, and a second one with Arimoto's strong converse exponent (above capacity) or the sphere-packing exponent (below the critical rate).","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"356 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133175895","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933441
K. Ohno, M. Itami, T. Ikegami
This paper discusses the primary systems detection technique for the OFDM system to share the spectrum among several radio systems such as UWB and other narrow band systems. In the iterative detection scheme, the received signals are assumed to be sum of the sinusoidal signals, and the coefficients of the sinusoidal signal to be minimized the error function by using Newton method. The detected amplitude is compared with the threshold value to detect usage of the primary systems. And frequency band of the primary systems also can be detected. However the calculation amounts are increased since iterative procedures are utilized. In this paper, the number of iterations for Newton method and the sine signal detection is considered to reduce the calculation amounts. The error of the coefficients estimation, miss-Detection Error Rate (DER) and False Alarm Rate (FAR) are evaluated and the performances are compared with the conventional technique using FFT.
{"title":"Iterative primary systems detection and complexity reduction for spectrum sharing technique","authors":"K. Ohno, M. Itami, T. Ikegami","doi":"10.1109/ISWCS.2014.6933441","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933441","url":null,"abstract":"This paper discusses the primary systems detection technique for the OFDM system to share the spectrum among several radio systems such as UWB and other narrow band systems. In the iterative detection scheme, the received signals are assumed to be sum of the sinusoidal signals, and the coefficients of the sinusoidal signal to be minimized the error function by using Newton method. The detected amplitude is compared with the threshold value to detect usage of the primary systems. And frequency band of the primary systems also can be detected. However the calculation amounts are increased since iterative procedures are utilized. In this paper, the number of iterations for Newton method and the sine signal detection is considered to reduce the calculation amounts. The error of the coefficients estimation, miss-Detection Error Rate (DER) and False Alarm Rate (FAR) are evaluated and the performances are compared with the conventional technique using FFT.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132050657","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933396
Z. Altman, M. Amirijoo, F. Gunnarsson, Hendrik Hoffmann, I. Kovács, D. Laselva, Bart Sas, K. Spaey, Abdoulaye Tall, H. V. D. Berg, K. Zetterberg
With an increasing number of SON functions deployed in cellular radio networks, conflicts between the actions proposed by independently-designed and distributed SON functions may arise. The process of minimizing the occurrence, and the consequences, of such conflicts is referred to as SON coordination. SON coordination can be achieved either by a separate entity, a SON coordinator, controlling the actions of each SON function during operation, or in the design of the SON functions as such, through a conflict free SON design. In both cases, the SON functions should be designed in a way compliant with the coordination method used. This paper proposes a number of SON design principles to apply in order to achieve this. In the case of an operational SON coordinator, SON functions should be able to deal with the possible actions that are taken by the SON coordination function in order not to worsen the problems experienced in the network. In the case of conflict free SON design the aim is at removing potential conflicts already in the design phase. The ambition of this paper is not to provide a complete set of design guidelines that address all aspects. Instead, the target is to open up the discussion on the distributed SON design principles in the community.
{"title":"On design principles for self-organizing network functions","authors":"Z. Altman, M. Amirijoo, F. Gunnarsson, Hendrik Hoffmann, I. Kovács, D. Laselva, Bart Sas, K. Spaey, Abdoulaye Tall, H. V. D. Berg, K. Zetterberg","doi":"10.1109/ISWCS.2014.6933396","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933396","url":null,"abstract":"With an increasing number of SON functions deployed in cellular radio networks, conflicts between the actions proposed by independently-designed and distributed SON functions may arise. The process of minimizing the occurrence, and the consequences, of such conflicts is referred to as SON coordination. SON coordination can be achieved either by a separate entity, a SON coordinator, controlling the actions of each SON function during operation, or in the design of the SON functions as such, through a conflict free SON design. In both cases, the SON functions should be designed in a way compliant with the coordination method used. This paper proposes a number of SON design principles to apply in order to achieve this. In the case of an operational SON coordinator, SON functions should be able to deal with the possible actions that are taken by the SON coordination function in order not to worsen the problems experienced in the network. In the case of conflict free SON design the aim is at removing potential conflicts already in the design phase. The ambition of this paper is not to provide a complete set of design guidelines that address all aspects. Instead, the target is to open up the discussion on the distributed SON design principles in the community.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132397690","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933404
Marwa El Hefnawy, G. Dietl, G. Kramer
Spectral shaping is applied to Faster-Than-Nyquist (FTN) signaling to improve information rates. Under a transmit power constraint, the best shape is an inverse filter but for root raised cosine pulses this requires infinite power at the shaper input. Both input and output power constraints at the shaper are thus proposed as a solution to maximize the information rate while still guaranteeing practicality.
{"title":"Spectral shaping for faster-than-Nyquist signaling","authors":"Marwa El Hefnawy, G. Dietl, G. Kramer","doi":"10.1109/ISWCS.2014.6933404","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933404","url":null,"abstract":"Spectral shaping is applied to Faster-Than-Nyquist (FTN) signaling to improve information rates. Under a transmit power constraint, the best shape is an inverse filter but for root raised cosine pulses this requires infinite power at the shaper input. Both input and output power constraints at the shaper are thus proposed as a solution to maximize the information rate while still guaranteeing practicality.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123207221","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933448
R. Ajgou, S. Sbaa, S. Ghendir, A. Chamsa, A. Taleb-Ahmed
A remote text-independent automatic speaker recognition system has been proposed for communication channel in VoIP applications. The proposed system employs a robust speech feature that uses an efficient speech activity detection algorithm and GMM model. Mel-Frequency Cepstral coefficient (MFCC) is a very useful feature for speech processing in clean conditions but it deteriorates in the presence of noise. Feature extraction framework based on the well known MFCC and autoregressive model (AR) features has been proposed. TIMIT database with speech from 630 speakers has been used in Matlab simulation. The first four utterances for each speaker could be defined as the training set while 1 utterance as the test set. The use of AR-MFCC approach has provided significant improvements in identification rate accuracy when compared with MFCC in noisy environment. However, in terms of runtime, AR-MFCC requires more time to execute than MFCC.
{"title":"Robust remote speaker recognition system based on AR-MFCC features and efficient speech activity detection algorithm","authors":"R. Ajgou, S. Sbaa, S. Ghendir, A. Chamsa, A. Taleb-Ahmed","doi":"10.1109/ISWCS.2014.6933448","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933448","url":null,"abstract":"A remote text-independent automatic speaker recognition system has been proposed for communication channel in VoIP applications. The proposed system employs a robust speech feature that uses an efficient speech activity detection algorithm and GMM model. Mel-Frequency Cepstral coefficient (MFCC) is a very useful feature for speech processing in clean conditions but it deteriorates in the presence of noise. Feature extraction framework based on the well known MFCC and autoregressive model (AR) features has been proposed. TIMIT database with speech from 630 speakers has been used in Matlab simulation. The first four utterances for each speaker could be defined as the training set while 1 utterance as the test set. The use of AR-MFCC approach has provided significant improvements in identification rate accuracy when compared with MFCC in noisy environment. However, in terms of runtime, AR-MFCC requires more time to execute than MFCC.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123605326","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933477
A. Dziri, C. Alexandre, R. Zakaria, D. L. Ruyet
This paper investigates the design of a potential Software Defined Radio (SDR) based prototype for Filter Bank based Multi-Carrier Transmission. It allows for implementing and testing transmitter and receiver in real-time on Universal Software Radio Peripheral (USRP) by using two USRP boards. Additionally, an implementation of some classic channel models in a separate USRP board has been used for emulating a propagation channel. The presented prototyping system supports FBMC waveform but also Orthogonal Frequency Division Multi-carriers(OFDM) one using MATLAB routines. With this motivation, we propose a study on real-time decoding of Offset Quadrature Amplitude Modulation FBMC (OQAM-FBMC) radio frames. In this system, data recovery at the receiver is very sensitive to time and frequency synchronization of the frames. This problem was addressed in many theoretical research works. However, considering its practical aspects in the context of a realtime radio transmission, a signal processing block is required to satisfy a trade-off between the accuracy and the latency. We especially recognize different limits, imposed by both hardware and software entities, to the real-time system.
{"title":"SDR based prototype for filter bank based multi-carrier transmission","authors":"A. Dziri, C. Alexandre, R. Zakaria, D. L. Ruyet","doi":"10.1109/ISWCS.2014.6933477","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933477","url":null,"abstract":"This paper investigates the design of a potential Software Defined Radio (SDR) based prototype for Filter Bank based Multi-Carrier Transmission. It allows for implementing and testing transmitter and receiver in real-time on Universal Software Radio Peripheral (USRP) by using two USRP boards. Additionally, an implementation of some classic channel models in a separate USRP board has been used for emulating a propagation channel. The presented prototyping system supports FBMC waveform but also Orthogonal Frequency Division Multi-carriers(OFDM) one using MATLAB routines. With this motivation, we propose a study on real-time decoding of Offset Quadrature Amplitude Modulation FBMC (OQAM-FBMC) radio frames. In this system, data recovery at the receiver is very sensitive to time and frequency synchronization of the frames. This problem was addressed in many theoretical research works. However, considering its practical aspects in the context of a realtime radio transmission, a signal processing block is required to satisfy a trade-off between the accuracy and the latency. We especially recognize different limits, imposed by both hardware and software entities, to the real-time system.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129145014","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933349
S. Hahn, T. Kürner
Self-Organising Network (SON) functions change parameters in the (mobile) network based on input and SON configuration parameters. However, it is still unclear how the behaviour of the SON function itself and the impact on the network changes by modifying the SON configuration parameters. The herein proposed SON function performance model (SFPM) shows how the impact on KPIs changes by varying SON function configuration parameters. Moreover it opens up the possibility to steer the network performance towards a certain direction by applying appropriate SON configuration parameters that have been derived by the SFPM.
{"title":"Managing and altering mobile radio networks by using SON function performance models","authors":"S. Hahn, T. Kürner","doi":"10.1109/ISWCS.2014.6933349","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933349","url":null,"abstract":"Self-Organising Network (SON) functions change parameters in the (mobile) network based on input and SON configuration parameters. However, it is still unclear how the behaviour of the SON function itself and the impact on the network changes by modifying the SON configuration parameters. The herein proposed SON function performance model (SFPM) shows how the impact on KPIs changes by varying SON function configuration parameters. Moreover it opens up the possibility to steer the network performance towards a certain direction by applying appropriate SON configuration parameters that have been derived by the SFPM.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121869047","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933379
Hamidreza R. Kermajani, Carles Gomez
This paper presents an analytical model for estimating the network convergence time of IPv6 Routing Protocol for Low-power and Lossy Networks (RPL) in a static chain topology network of IEEE 802.15.4 nodes, in the presence of bit errors. The model presented is validated by extensive simulation results. We show that performance degradation may be noticed by a user for BER values around or greater than 8·10-4.
{"title":"Modeling the network convergence time in RPL in error-prone, IEEE 802.15.4 chain topology multihop networks","authors":"Hamidreza R. Kermajani, Carles Gomez","doi":"10.1109/ISWCS.2014.6933379","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933379","url":null,"abstract":"This paper presents an analytical model for estimating the network convergence time of IPv6 Routing Protocol for Low-power and Lossy Networks (RPL) in a static chain topology network of IEEE 802.15.4 nodes, in the presence of bit errors. The model presented is validated by extensive simulation results. We show that performance degradation may be noticed by a user for BER values around or greater than 8·10-4.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122662923","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933413
Ye Tian, B. Denby, Iness Ahriz, P. Roussel-Ragot, G. Dreyfus
The article presents an indoor localization scheme for mobile devices based on GSM Received Signal Strength fingerprints combined with embedded sensor information and an area site map. Displacements of a mobile user are first estimated using a sensor dead-reckoning approach that adapts stride length to different users and environments, and a dynamically switched orientation estimation scheme responding to orientation changes of the mobile device. Positions derived from GSM fingerprints, along with constraints imposed by a site map, are then integrated using a particle filter in order to prevent the accumulation of dead-reckoning errors over time. The study demonstrates that a standard handset with cellular network access and embedded inertial sensors can provide a good solution for indoor localization.
{"title":"Hybrid indoor localization using GSM fingerprints, embedded sensors and a particle filter","authors":"Ye Tian, B. Denby, Iness Ahriz, P. Roussel-Ragot, G. Dreyfus","doi":"10.1109/ISWCS.2014.6933413","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933413","url":null,"abstract":"The article presents an indoor localization scheme for mobile devices based on GSM Received Signal Strength fingerprints combined with embedded sensor information and an area site map. Displacements of a mobile user are first estimated using a sensor dead-reckoning approach that adapts stride length to different users and environments, and a dynamically switched orientation estimation scheme responding to orientation changes of the mobile device. Positions derived from GSM fingerprints, along with constraints imposed by a site map, are then integrated using a particle filter in order to prevent the accumulation of dead-reckoning errors over time. The study demonstrates that a standard handset with cellular network access and embedded inertial sensors can provide a good solution for indoor localization.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114441677","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 : 2014-10-23DOI: 10.1109/ISWCS.2014.6933471
Dimitris Kelaidonis, P. Vlacheas, V. Foteinos, Antonis Moustakos, A. Georgakopoulos, T. Michalareas, Z. Feng, Meng Dexiang, P. Demestichas
This work presents a cognitive framework and associated platform for Smart Energy Management of Wireless Technologies and mobile applications (ARTEMIS), targeting the reduction of the energy consumption that derives from wireless technologies and applications, by considering a huge set of different aspects and actors, i.e. starting from the infrastructure and the network operator, and ending at the application part and the service provider as well as the end-user. In particular, ARTEMIS includes cognitive technologies, which penetrate four (4) levels: the Application Level, the System Level, the Network Level and the Device Level. A set of different use cases have been described, aiming to infer conclusions about all the possible aspects of the ARTEMIS platform that should be covered, such as functionality, usability, reliability, performance and supportability, across the platform's individual components. Further to that, the use cases can contribute to the illustration of the benefits of ARTEMIS and engage platform's stakeholders, as well as to ensure broad applicability of ARTEMIS concepts.
{"title":"Smart energy management of wireless technologies and mobile applications","authors":"Dimitris Kelaidonis, P. Vlacheas, V. Foteinos, Antonis Moustakos, A. Georgakopoulos, T. Michalareas, Z. Feng, Meng Dexiang, P. Demestichas","doi":"10.1109/ISWCS.2014.6933471","DOIUrl":"https://doi.org/10.1109/ISWCS.2014.6933471","url":null,"abstract":"This work presents a cognitive framework and associated platform for Smart Energy Management of Wireless Technologies and mobile applications (ARTEMIS), targeting the reduction of the energy consumption that derives from wireless technologies and applications, by considering a huge set of different aspects and actors, i.e. starting from the infrastructure and the network operator, and ending at the application part and the service provider as well as the end-user. In particular, ARTEMIS includes cognitive technologies, which penetrate four (4) levels: the Application Level, the System Level, the Network Level and the Device Level. A set of different use cases have been described, aiming to infer conclusions about all the possible aspects of the ARTEMIS platform that should be covered, such as functionality, usability, reliability, performance and supportability, across the platform's individual components. Further to that, the use cases can contribute to the illustration of the benefits of ARTEMIS and engage platform's stakeholders, as well as to ensure broad applicability of ARTEMIS concepts.","PeriodicalId":431852,"journal":{"name":"2014 11th International Symposium on Wireless Communications Systems (ISWCS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117119649","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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