61 research outputs found

    Deep Learning for QoT Estimation in SMF and FMF Links

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    We explore deep learning-based classification and regression algorithms to estimate quality of transmission in single-mode and few-mode fiber links. Both approaches are shown to be effective and low complexity

    Rate Optimized Probabilistic Shaping-Based Transmission Over Field Deployed Coupled-Core 4-Core-Fiber

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    Multi-core fiber (MCF) transmission is a promising solution to support ever-increasing future traffic demands. Compared with uncoupled-core MCFs [1], the induced strong coupling in coupled-core (CC)-MCFs reduces the nonlinearity impact [2]. Transmission in these fibers leverages both spatial and wavelength division multiplexing and it has been experimentally tested mainly considering uniform quadrature amplitude modulation (QAM) formats [3]. Spectral efficiency can be further optimized by employing probabilistic shaping (PS) but the joint use of CC-MCF and PS has been rarely investigated [4]. In this paper, we present a transmission of PS signals through an infrastructure based on a CC-four core fiber (CC-4CF) deployed in the city of L'Aquila, Italy [5]. We ran experiments comparing the performance of standard polarization multiplexed 16QAM and PS-32QAM signals at a symbol rate of 30 GBaud: 800 Gbps net rate considering the spatial super-channel over four cores. We used the generalized mutual information (GMI) as performance metric and averaged over the 8 polarizations concidering the central channel. A realistic threshold (GMIth) of 3.6 bits/symbol (per spatial mode and polarization) has been set as a target: it is a typical value that guarantees post-FEC error-free transmission for most realistic SD-FEC

    Correction to: Comparison of Vitamin B12, Vitamin D, and Folic Acid Blood Levels in Plumbism Patients and Controls in Eastern Iran (Biological Trace Element Research, (2021), 199, 1, (9-17), 10.1007/s12011-020-02119-6)

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    The original version of this article unfortunately contained mistakes. & The name of �Namam Ali Azadi� is now corrected in the author group & Fourth to seventh sentence of the Abstract section should be �The results indicated that the mean vitamin B12, vitamin D, and folic acid levels for the case group were 517.3 ± 419.4 pg/ml, 25.1 ± 10.8 ng/ml, and 9.2 ± 6.1 ng/ml, respectively. Mean folic acid level in the case group was significantly lower than control group (Fisher exact test, P < 0.001), whereas the mean of the vitamin D levels at the case group was no significantly higher than the control group (Fisher exact test, P = 0.059). Moreover, mean vitamin B12 levels were significantly different between the case and control groups (Fisher exact test, P = 0.009). In the control group, three patients had folic acid below normal level (< 6 ng/mL), while twelve subjects at case group had folic acid below normal level (P < 0.05).Also, none of the control group had low vitamin B12 concentrations (< 180 pg/ml), while seven subjects of case group had vitamin B12 below normal level (P < 0.05).� & In page 6, Discussion part, 4th paragraph: We found that mean blood folate levels in the lead-poisoned patients, who had a mean BLL of 66 ± 37. 3 µg/dl, were significantly lower than in healthy subjects (9.2 ± 6.1 ng/ml vs. 12.70 pg/ml). © 2020, Springer Science+Business Media, LLC, part of Springer Nature
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