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Not AvailableAn attempt was made to establish association pattern between dimension of fish and otolith to expedite morphometric variations of geographically isolated stocks of Tenualosa ilisha (Hamilton, 1822), from three diverse ecosystems; viz., an estuarine (brackish water), a riverine (freshwater) and a lacustrine (freshwater) ecosystem. Sampling was carried out during the period from September 2017 to February 2019 and a total of 196 otoliths were sampled from Narmada Estuary (n=69), Brahmaputra River (n=75) and Ukai Reservoir (n=52) of India. Mean otolith length recorded was 3.55±0.14 mm, 5.18±0.09 mm and 3.85±0.07 mm for samples collected from Narmada Estuary, Brahmaputra River and Ukai Reservoir respectively. Otolith length-weight relationship (OLWR) from three ecosystems showed negative allometric b values ranging from 1.9046-2.5048, with significant difference between Narmada Estuary and Brahmaputra River (p0.6); except for relationship between otolith width (OB) and TL in samples from Brahmaputra River (R2=0.459). Present study provides first-hand information on association pattern of dimension of fish body and otolith of T. ilisha which can be used in geographical mapping of stock profile of the species.Not Availabl

Low-timing-sensitivity waveform design for carrierless amplitude and phase modulation in visible light communications

The carrierless amplitude and phase (CAP) modulation is a promising candidate for visible light communication (VLC) because of its high frequency efficiency and low implementation complexity. However, the CAP receiver is highly sensitive to timing errors because of the bad eye diagram performance and requires a complex synchronisation circuit. In this study, the conventional CAP pulse is extended to a generalised CAP pulse. The zero inter-symbol interference (zero-ISI) and the zero cross-channel interference (zero-CCI) constraints are assumed for the generalised CAP pulses. Two new sets of wider eye opened two-dimensional (2D) CAP pulses and a set of frequency efficient 3D CAP pulses are proposed to meet the zero-ISI and zero-CCI constraints for VLC. Simulation results show that the proposed new 2D CAP pulses are more tolerant to the timing offset than the existing CAP pulses in VLC systems, but the corresponding bit error rate performances are poorer when the accurate timing synchronisation is obtained. Moreover, the proposed new 3D CAP pulses are more sensitive to the timing offset than the existing CAP pulses