Pub Date : 2017-02-01DOI: 10.1109/ITA.2017.8023481
Nathan Wong, K. Vakilinia, Haobo Wang, S. V. S. Ranganathan, R. Wesel
This paper applies the sequential differential optimization (SDO) algorithm to optimize the transmission lengths of incremental redundancy for a 1024-state tail-biting convolutional code. The tail-biting reliability-output Viterbi algorithm is used to determine whether to inform the transmitter that a message has been successfully received or to request that the transmitter provide additional convolutional code bits. In order to maximize the average throughput, SDO is used to determine the rate of the initial codeword and the number of bits of incremental redundancy to be sent in each increment. With the help of SDO, this paper demonstrates a system that achieves 86.3 percent of the binary-input AWGN capacity (for SNR 2 dB) with an average blocklength of 115.5 symbols.
{"title":"Sequential differential optimization of incremental redundancy transmission lengths: An example with tail-biting convolutional codes","authors":"Nathan Wong, K. Vakilinia, Haobo Wang, S. V. S. Ranganathan, R. Wesel","doi":"10.1109/ITA.2017.8023481","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023481","url":null,"abstract":"This paper applies the sequential differential optimization (SDO) algorithm to optimize the transmission lengths of incremental redundancy for a 1024-state tail-biting convolutional code. The tail-biting reliability-output Viterbi algorithm is used to determine whether to inform the transmitter that a message has been successfully received or to request that the transmitter provide additional convolutional code bits. In order to maximize the average throughput, SDO is used to determine the rate of the initial codeword and the number of bits of incremental redundancy to be sent in each increment. With the help of SDO, this paper demonstrates a system that achieves 86.3 percent of the binary-input AWGN capacity (for SNR 2 dB) with an average blocklength of 115.5 symbols.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123490507","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023451
J. Gibson
We examine the common assumptions of high rate, independence, and optimal prediction often used in the theoretical performance analyses of differential predictive coding. We demonstrate that these assumptions are never valid for this structure. We then perform an analysis of the performance of differential predictive coding without these assumptions and show that not only are these assumptions invalid, the results obtained using these assumptions underestimate system performance. Both theoretical and practical illustrations are provided.
{"title":"On the high rate, independence, and optimal prediction assumptions in predictive coding","authors":"J. Gibson","doi":"10.1109/ITA.2017.8023451","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023451","url":null,"abstract":"We examine the common assumptions of high rate, independence, and optimal prediction often used in the theoretical performance analyses of differential predictive coding. We demonstrate that these assumptions are never valid for this structure. We then perform an analysis of the performance of differential predictive coding without these assumptions and show that not only are these assumptions invalid, the results obtained using these assumptions underestimate system performance. Both theoretical and practical illustrations are provided.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127312342","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023456
Quynh Nguyen, B. Krishnamachari
For intermittently connected mobile networks such as sparsely-deployed vehicular networks, it is of great interest to characterize the distribution of encounter times. We consider a very general mobility model in which each device is assumed to be moving through a given graph following a general random walk with arbitrary transition probabilities. We consider first the pairwise inter-encounter time distribution for a pair of random walkers and present a recursive polynomial-time computation that yields the exact solution. We then consider the individual-to-any inter-encounter time (i.e., the time between contacts of a particular walker with any of the other walkers in the population). For this harder problem, we give an approximate computation that is also polynomial time. We validate the accuracy of the presented solutions using numerical simulations. We discuss how the model can be generalized to consider multiple populations.
{"title":"Computing inter-encounter time distributions for multiple random walkers on graphs","authors":"Quynh Nguyen, B. Krishnamachari","doi":"10.1109/ITA.2017.8023456","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023456","url":null,"abstract":"For intermittently connected mobile networks such as sparsely-deployed vehicular networks, it is of great interest to characterize the distribution of encounter times. We consider a very general mobility model in which each device is assumed to be moving through a given graph following a general random walk with arbitrary transition probabilities. We consider first the pairwise inter-encounter time distribution for a pair of random walkers and present a recursive polynomial-time computation that yields the exact solution. We then consider the individual-to-any inter-encounter time (i.e., the time between contacts of a particular walker with any of the other walkers in the population). For this harder problem, we give an approximate computation that is also polynomial time. We validate the accuracy of the presented solutions using numerical simulations. We discuss how the model can be generalized to consider multiple populations.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134196262","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023471
Yuxuan Xing, H. Seferoglu
The dramatic increase in data and connectivity demand, in addition to heterogeneous device capabilities, poses a challenge for future wireless networks. One of the promising solutions is Device-to-Device (D2D) networking. D2D networking, advocating the idea of connecting two or more devices directly without traversing the core network, is promising to address the increasing data and connectivity demand. In this paper, we consider D2D networks, where devices with heterogeneous capabilities including computing power, energy limitations, and incentives participate in D2D activities heterogeneously. We develop (i) a device-aware routing and scheduling algorithm (DARS) by taking into account device capabilities, and (ii) a multi-hop D2D testbed using Android-based smartphones and tablets by exploiting Wi-Fi Direct and legacy Wi-Fi connections. We show that DARS significantly improves throughput in our testbed as compared to state-of-the-art.
{"title":"Device-aware routing and scheduling in multi-hop Device-to-Device networks","authors":"Yuxuan Xing, H. Seferoglu","doi":"10.1109/ITA.2017.8023471","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023471","url":null,"abstract":"The dramatic increase in data and connectivity demand, in addition to heterogeneous device capabilities, poses a challenge for future wireless networks. One of the promising solutions is Device-to-Device (D2D) networking. D2D networking, advocating the idea of connecting two or more devices directly without traversing the core network, is promising to address the increasing data and connectivity demand. In this paper, we consider D2D networks, where devices with heterogeneous capabilities including computing power, energy limitations, and incentives participate in D2D activities heterogeneously. We develop (i) a device-aware routing and scheduling algorithm (DARS) by taking into account device capabilities, and (ii) a multi-hop D2D testbed using Android-based smartphones and tablets by exploiting Wi-Fi Direct and legacy Wi-Fi connections. We show that DARS significantly improves throughput in our testbed as compared to state-of-the-art.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114858589","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023460
Muddassar Hussain, Nicolò Michelusi
Millimeter wave communications rely on narrow-beam transmissions to cope with the strong signal attenuation at these frequencies, thus demanding precise beam alignment between transmitter and receiver. The communication overhead incurred to achieve beam alignment may become a severe impairment in mobile networks. This paper addresses the problem of optimizing beam alignment acquisition, with the goal of maximizing throughput. Specifically, the algorithm jointly determines the portion of time devoted to beam alignment acquisition, as well as, within this portion of time, the optimal beam search parameters, using the framework of Markov decision processes. It is proved that a bisection search algorithm is optimal, and that it outperforms exhaustive and iterative search algorithms proposed in the literature. The duration of the beam alignment phase is optimized so as to maximize the overall throughput. The numerical results show that the throughput, optimized with respect to the duration of the beam alignment phase, achievable under the exhaustive algorithm is 88.3% lower than that achievable under the bisection algorithm. Similarly, the throughput achievable by the iterative search algorithm for a division factor of 4 and 8 is, respectively, 12.8% and 36.4% lower than that achievable by the bisection algorithm.
{"title":"Throughput optimal beam alignment in millimeter wave networks","authors":"Muddassar Hussain, Nicolò Michelusi","doi":"10.1109/ITA.2017.8023460","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023460","url":null,"abstract":"Millimeter wave communications rely on narrow-beam transmissions to cope with the strong signal attenuation at these frequencies, thus demanding precise beam alignment between transmitter and receiver. The communication overhead incurred to achieve beam alignment may become a severe impairment in mobile networks. This paper addresses the problem of optimizing beam alignment acquisition, with the goal of maximizing throughput. Specifically, the algorithm jointly determines the portion of time devoted to beam alignment acquisition, as well as, within this portion of time, the optimal beam search parameters, using the framework of Markov decision processes. It is proved that a bisection search algorithm is optimal, and that it outperforms exhaustive and iterative search algorithms proposed in the literature. The duration of the beam alignment phase is optimized so as to maximize the overall throughput. The numerical results show that the throughput, optimized with respect to the duration of the beam alignment phase, achievable under the exhaustive algorithm is 88.3% lower than that achievable under the bisection algorithm. Similarly, the throughput achievable by the iterative search algorithm for a division factor of 4 and 8 is, respectively, 12.8% and 36.4% lower than that achievable by the bisection algorithm.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116077069","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023479
R. Raman, Haizi Yu, L. Varshney
Shannon's mutual information measures the degree of mutual dependence between two random variables. Two related information functionals have also been developed in the literature: multiinformation, a multivariate extension of mutual information; and lautum information, the Csiszár conjugate of mutual information. In this work, we define illum information, the multivariate extension of lautum information and the Csiszár conjugate of multiinformation. We provide operational interpretations of this functional, including in the problem of independence testing of a set of random variables. Further, we also provide informational characterizations of illum information such as the data processing inequality and the chain rule for distributions on tree-structured graphical models. Finally, as illustrative examples, we compute the illum information for Ising models and Gauss-Markov random fields.
{"title":"Illum information","authors":"R. Raman, Haizi Yu, L. Varshney","doi":"10.1109/ITA.2017.8023479","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023479","url":null,"abstract":"Shannon's mutual information measures the degree of mutual dependence between two random variables. Two related information functionals have also been developed in the literature: multiinformation, a multivariate extension of mutual information; and lautum information, the Csiszár conjugate of mutual information. In this work, we define illum information, the multivariate extension of lautum information and the Csiszár conjugate of multiinformation. We provide operational interpretations of this functional, including in the problem of independence testing of a set of random variables. Further, we also provide informational characterizations of illum information such as the data processing inequality and the chain rule for distributions on tree-structured graphical models. Finally, as illustrative examples, we compute the illum information for Ising models and Gauss-Markov random fields.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133585247","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023469
S. Eshghi, V. Preciado, S. Sarkar, S. Venkatesh, Qing Zhao, R. D’Souza, A. Swami
We obtain optimal strategies for the allocation of influence budget across multiple channels and across time for an external influencer, e.g., a political campaign, seeking to maximize its effect on an election given a network of agents with linear consensus-seeking opinion dynamics. We show that for a general set of objective functions, the optimal influence strategy at every time uses all channels at either their maximum rate or not at all. Furthermore, we prove that the number of switches between these extremes is bounded above both by a term that is typically much smaller than the number of agents. This means that the optimal influence strategy is to exert maximum effort in waves for every channel, and then cease effort and let the effects propagate. We also show that at the beginning, the total cost-adjusted reach of a channel determines its relative value, while targeting matters more closer to election time. We demonstrate that the optimal influence structures are easily computable in several practical cases. We explicitly characterize the optimal controls for the case of linear objective functions via a closed form. Finally, we see that in the canonical election example, identifying late-deciders approximately determines the optimal campaign resource allocation strategy.
{"title":"Spread, then target, and advertise in waves: Optimal capital allocation across advertising channels","authors":"S. Eshghi, V. Preciado, S. Sarkar, S. Venkatesh, Qing Zhao, R. D’Souza, A. Swami","doi":"10.1109/ITA.2017.8023469","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023469","url":null,"abstract":"We obtain optimal strategies for the allocation of influence budget across multiple channels and across time for an external influencer, e.g., a political campaign, seeking to maximize its effect on an election given a network of agents with linear consensus-seeking opinion dynamics. We show that for a general set of objective functions, the optimal influence strategy at every time uses all channels at either their maximum rate or not at all. Furthermore, we prove that the number of switches between these extremes is bounded above both by a term that is typically much smaller than the number of agents. This means that the optimal influence strategy is to exert maximum effort in waves for every channel, and then cease effort and let the effects propagate. We also show that at the beginning, the total cost-adjusted reach of a channel determines its relative value, while targeting matters more closer to election time. We demonstrate that the optimal influence structures are easily computable in several practical cases. We explicitly characterize the optimal controls for the case of linear objective functions via a closed form. Finally, we see that in the canonical election example, identifying late-deciders approximately determines the optimal campaign resource allocation strategy.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126418662","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023464
Siddhartha S. Borkotoky, M. Pursley
We investigate two approaches to fountain-coded broadcast file distribution in an ad hoc packet radio network. In the first method, all destinations receive fountain-coded packets directly from the source. In the second method, after one destination obtains the file, it acts as a relay node by applying continued fountain coding to the file and sending the encoded packets to other destinations. The other destinations combine the fountain-coded packets they received from the source with those they obtain from the relay node. We compare the performance of the two methods when they are employed in a network whose links have Rayleigh fading. As performance benchmarks, we also examine two conventional broadcast techniques that use automatic repeat request (ARQ) for retransmission of erased packets.
{"title":"A comparison of two methods for fountain-coded file distribution in an ad hoc network with relays","authors":"Siddhartha S. Borkotoky, M. Pursley","doi":"10.1109/ITA.2017.8023464","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023464","url":null,"abstract":"We investigate two approaches to fountain-coded broadcast file distribution in an ad hoc packet radio network. In the first method, all destinations receive fountain-coded packets directly from the source. In the second method, after one destination obtains the file, it acts as a relay node by applying continued fountain coding to the file and sending the encoded packets to other destinations. The other destinations combine the fountain-coded packets they received from the source with those they obtain from the relay node. We compare the performance of the two methods when they are employed in a network whose links have Rayleigh fading. As performance benchmarks, we also examine two conventional broadcast techniques that use automatic repeat request (ARQ) for retransmission of erased packets.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"163 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123506868","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023453
Naveen Goela, J. Bolot
With decreasing costs for DNA synthesis and sequencing, ultra-dense DNA storage is an emerging, viable technology. The original proof of concept [1]–[3] has yielded several experiments of larger scale demonstrating archival storage in DNA molecules [4]–[7]. In particular, a recent collaboration by Harvard and Technicolor announced the storage of 22 MB of data in synthetic DNA [4]. Primarily, existing storage systems utilize high-fidelity synthesizers. For synthesizers which incur non-negligible insertions and deletions, a large fraction of the oligonucleotide segments produced have unequal, variable lengths. This talk overviews methods to correct for synchronization errors in variable-length segments using synchronization codes (e.g., [8], [9]).
{"title":"Advances in DNA storage","authors":"Naveen Goela, J. Bolot","doi":"10.1109/ITA.2017.8023453","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023453","url":null,"abstract":"With decreasing costs for DNA synthesis and sequencing, ultra-dense DNA storage is an emerging, viable technology. The original proof of concept [1]–[3] has yielded several experiments of larger scale demonstrating archival storage in DNA molecules [4]–[7]. In particular, a recent collaboration by Harvard and Technicolor announced the storage of 22 MB of data in synthetic DNA [4]. Primarily, existing storage systems utilize high-fidelity synthesizers. For synthesizers which incur non-negligible insertions and deletions, a large fraction of the oligonucleotide segments produced have unequal, variable lengths. This talk overviews methods to correct for synchronization errors in variable-length segments using synchronization codes (e.g., [8], [9]).","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"26 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124609837","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 : 2017-02-01DOI: 10.1109/ITA.2017.8023454
Kang Gao, N. Estes, B. Hochwald, J. Chisum, J. N. Laneman
We analyze a one-bit wireless transceiver whose architecture is simple enough that its power versus performance profile can be modeled analytically. We then utilize multiple such transceivers in a communication system operating at millimeter-wave carrier frequencies. Various aspects of the system are analyzed, including the optimum achievable throughput for a given amount of total consumed power. An analogy is drawn between the “transceiver cell” proposed herein and a “computational cell” commonly used in neural networks that allows us to apply neural-network type algorithms to aid in difficult tasks such as channel estimation for a large number of transceivers.
{"title":"Power-performance analysis of a simple one-bit transceiver","authors":"Kang Gao, N. Estes, B. Hochwald, J. Chisum, J. N. Laneman","doi":"10.1109/ITA.2017.8023454","DOIUrl":"https://doi.org/10.1109/ITA.2017.8023454","url":null,"abstract":"We analyze a one-bit wireless transceiver whose architecture is simple enough that its power versus performance profile can be modeled analytically. We then utilize multiple such transceivers in a communication system operating at millimeter-wave carrier frequencies. Various aspects of the system are analyzed, including the optimum achievable throughput for a given amount of total consumed power. An analogy is drawn between the “transceiver cell” proposed herein and a “computational cell” commonly used in neural networks that allows us to apply neural-network type algorithms to aid in difficult tasks such as channel estimation for a large number of transceivers.","PeriodicalId":305510,"journal":{"name":"2017 Information Theory and Applications Workshop (ITA)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115102179","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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