The Experts below are selected from a list of 174 Experts worldwide ranked by ideXlab platform
Jiaxin Liang - One of the best experts on this subject based on the ideXlab platform.
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Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
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ICC - Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
Yulin Shao - One of the best experts on this subject based on the ideXlab platform.
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Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
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ICC - Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
Soung Chang Liew - One of the best experts on this subject based on the ideXlab platform.
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Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
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ICC - Sporadic Ultra-Time-Critical Messaging in V2X
2018 IEEE International Conference on Communications (ICC), 2018Co-Authors: Yulin Shao, Soung Chang Liew, Jiaxin LiangAbstract:Life-critical warning message, abbreviated as warning message, is a special event-driven message that carries emergency warning information in Vehicle-to-Everything (V2X). Two important characteristics that distinguish warning messages from ordinary vehicular messages are sporadicity and ultra-time-criticality. This paper puts forth a medium-access control (MAC) protocol for warning messages. To circumvent potential inefficiency arisen from sporadicity, we propose an override network architecture whereby warning messages are delivered on the network of the ordinary vehicular messages. Specifically, a vehicle with a warning message first sends an Interrupt Signal to pre- empt the transmission of ordinary messages, so that the warning message can use the wireless spectrum originally allocated to ordinary messages. In this way, no exclusive spectrum resources need to be pre-allocated to the sporadic warning messages. To meet the ultra-time- criticality requirement, we use advanced MAC techniques (e.g., coded ALOHA) to ensure highly reliable delivery of warning messages within an ultra-short time in the order of 10 ms. The overall MAC protocol operates by means of Interrupt-and-access. We investigate the use of spread spectrum sequences as Interrupt Signals. Simulation results show that the missed detection rate (MDR) of the Interrupt Signals can be very small given sufficient sequence length, e.g., when SIR is -32 dB, a 0.43 ms sequence (64512 symbols, 150 MHz) can guarantee an MDR of 0.0001. For channel access, simulation results indicate that coded ALOHA can potentially satisfy the ultra- time-criticality requirements of warning messages. In the stringent scenario where 30 emergency nodes broadcast warning messages simultaneously, the message loss rate can be kept lower than 0.0001 with delay less than 10 ms.
Angela J Yu - One of the best experts on this subject based on the ideXlab platform.
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phasic norepinephrine a neural Interrupt Signal for unexpected events
Network: Computation In Neural Systems, 2006Co-Authors: Peter Dayan, Angela J YuAbstract:Extensive animal studies indicate that the neuromodulator norepinephrine plays an important role in specific aspects of vigilance, attention and learning, putatively serving as a neural Interrupt or reset function. The activity of norepinephrine-releasing neurons in the locus coeruleus during attentional tasks is modulated not only by the animal's level of engagement and the sensory inputs, but also by temporally rich aspects of internal decision-making processes. Here, we propose that it is unexpected changes in the world within the context of a task that activate the noradrenergic Interrupt Signal. We quantify this idea in a Bayesian model of a well-studied visual discrimination task, demonstrating that the model captures a rich repertoire of noradrenergic responses at the sub-second temporal resolution.
Peter Dayan - One of the best experts on this subject based on the ideXlab platform.
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phasic norepinephrine is a neural Interrupt Signal for unexpected events in rapidly unfolding sensory sequences evidence from pupillometry
bioRxiv, 2018Co-Authors: Sijia Zhao, Peter Dayan, Frederic Dick, Shigeto Furukawa, Li Hiao, Maria ChaitAbstract:Summary The ability to track the statistics of our surroundings is a key computational challenge. A prominent theory (Dayan & Yu, 2006) proposes that the brain monitors for ‘unexpected uncertainty’ – events which deviate substantially from model predictions, indicating model failure. Norepinephrine (NE) is thought to play a key role in this process by serving as an Interrupt Signal, initiating model-resetting. However, evidence is from paradigms where participants actively monitored stimulus statistics. To determine whether NE routinely reports the statistical structure of our surroundings, even when not behaviourally relevant, we used rapid tone-pip sequences that contained perceptually salient pattern-changes associated with abrupt structural violations vs. emergence of regular structure. Phasic pupil dilations (PDR) were monitored to assess NE. We reveal a remarkable specificity: When not behaviourally relevant, only abrupt structural violations evoked a PDR. The results demonstrate that NE tracks ‘unexpected uncertainty’ on rapid time scales relevant to sensory Signals.
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phasic norepinephrine a neural Interrupt Signal for unexpected events
Network: Computation In Neural Systems, 2006Co-Authors: Peter Dayan, Angela J YuAbstract:Extensive animal studies indicate that the neuromodulator norepinephrine plays an important role in specific aspects of vigilance, attention and learning, putatively serving as a neural Interrupt or reset function. The activity of norepinephrine-releasing neurons in the locus coeruleus during attentional tasks is modulated not only by the animal's level of engagement and the sensory inputs, but also by temporally rich aspects of internal decision-making processes. Here, we propose that it is unexpected changes in the world within the context of a task that activate the noradrenergic Interrupt Signal. We quantify this idea in a Bayesian model of a well-studied visual discrimination task, demonstrating that the model captures a rich repertoire of noradrenergic responses at the sub-second temporal resolution.
