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Subjects identified concurrent synthetic vowel pairs that differed in relative amplitude and fundamental frequency (F 0). Subjects were allowed to report one or two vowels for each stimulus, rather than forced to report two vowels as was the case in previously reported experiments of the same type. At all relative amplitudes, identification was better at a fundamental frequency difference (⌬F 0) of 6% than at 0%, but the effect was larger when the target vowel amplitude was below that of the competing vowel ͑Ϫ10 or Ϫ20 dB͒. The existence of a ⌬F 0 effect when the target is weak relative to the competing vowel is interpreted as evidence that segregation occurs according to a mechanism of cancellation based on the harmonic structure of the competing vowel. Enhancement of the target based on its own harmonic structure is unlikely, given the difficulty of estimating the fundamental frequency of a weak target. Details of the pattern of identification as a function of amplitude and vowel pair were found to be incompatible with a current model of vowel segregation.

During the last 20 years, the advance of communication technologies has generated multiple exciting applications. However, classical cryptography, commonly adopted to secure current communication systems, can be jeopardized by the advent of quantum computers. Quantum key distribution (QKD) is a promising technology aiming to solve such a security problem. Unfortunately, current implementations of QKD systems show relatively low key rates, demand low channel noise and use ad hoc devices. In this work, we picture how to overcome the rate limitation by using a 37-core fibre to generate 2.86 Mbit s −1 per core that can be space multiplexed into the highest secret key rate of 105.7 Mbit s −1 to date. We also demonstrate, with off-the-shelf equipment, the robustness of the system by co-propagating a classical signal at 370 Gbit s −1 , paving the way for a shared quantum and classical communication network. * dabac@fotonik.dtu.dk, bdali@fotonik.dtu.dk These authors contributed equally to this work 1 arXiv:1911.05360v1 [quant-ph] 13 Nov 2019 of integration with the bright signals used in classical communications [17][18][19][20][21][22][23]. In this work, we show how to overcome the low rate and compatibility limitations by exploiting a 37-core multicore fibre (MCF) as a technology for quantum communications [24]. This technology allows for efficient key generation, enabling the highest secret key rate presented to date. Moreover, we co-propagate in all the 37 cores simultaneously a high-speed classical signal, showing that the quantum communication is only weakly perturbed by it, paving the way for a full-fleshed implementation in current communication infrastructures.

The new fuel property “particulate matter (PM) index” suggested by Aikawa et al. in their previous report, which reflects particulate matter emission potential of gasoline, has been shown to have a significant correlation with PM in port fuel injection engine. However, the particulate matter index applicability to direct-injection gasoline engines has not been well verified. The purpose of this study is to confirm the particulate matter index applicability to direct-injection gasoline engines. Results verified good correlation between particulate matter index and particulate matter emissions of a direct-injection gasoline engine, just as with the port fuel injection engine. The verification of particulate number emissions of the direct-injection gasoline engine on the US FTP-75 cycle indicated a high correlation with the particulate matter index. In particular, a significantly high correlation (R2 = 0.9644) was observed in the FTP-75 cold-start phase (Phase 1) in which the fuel influences are considered most evident. The filter PM (PM mass) was simultaneously measured, and its correlation with PM index was verified. The correlation with PM mass was slightly lower than with particulate number, but it also had a good correlation with PM index. This indicated that the PM index will apply well to DI gasoline engines.

Abstract:We demonstrate a 32-core dense space division multiplexed (DSDM) transmission of PDM-16QAM 20-WDM signals over 1644.8km with a record aggregate SE distance product of 331,300b/s/Hz·km employing a low-crosstalk 32-core fiber in a partial recirculating-loop system.