We employ a climate-driven hydrological water balance and sediment transport model (HydroTrend) to simulate future climate-driven sediment loads flowing into the Ganges-Brahmaputra-Meghna (GBM) mega-delta. The model was parameterised using high-quality topographic data and forced with daily temperature and precipitation data obtained from downscaled Regional Climate Model (RCM) simulations for the period 1971-2100. Three perturbed RCM model runs were selected to quantify the potential range of future climate conditions associated with the SRES A1B scenario. Fluvial sediment delivery rates to the GBM delta associated with these climate data sets are projected to increase under the influence of anthropogenic climate change, albeit with the magnitude of the increase varying across the two catchments. Of the two study basins, the Brahmaputra's fluvial sediment load is predicted to be more sensitive to future climate change. Specifically, by the middle part of the 21(st) century, our model results suggest that sediment loads increase (relative to the 1981-2000 baseline period) over a range of between 16% and 18% (depending on climate model run) for the Ganges, but by between 25% and 28% for the Brahmaputra. The simulated increase in sediment flux emanating from the two catchments further increases towards the end of the 21(st) century, reaching between 34% and 37% for the Ganges and between 52% and 60% for the Brahmaputra by the 2090s. The variability in these changes across the three climate change simulations is small compared to the changes, suggesting they represent a significant increase. The new data obtained in this study offer the first estimate of whether and how anthropogenic climate change may affect the delivery of fluvial sediment to the GBM delta, informing assessments of the future sustainability and resilience of one of the world's most vulnerable mega-deltas. Specifically, such significant increases in future sediment loads could increase the resilience of the delta to sea-level rise by giving greater potential for vertical accretion. However, these increased sediment fluxes may not be realised due to uncertainties in the monsoon related response to climate change or other human-induced changes in the catchment: this is a subject for further research.

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Currently, communication system requires multiband small antennas for 5G mobile applications. Driven this motivation, this paper proposes a multiband patch antenna for Wi-Fi, WiMAX and 5G applications. The proposed antenna can effectively operate at 2.4 GHz as Wi-Fi, 7.8 GHz as WiMAX and 33.5 GHz as 5G communication purposes. The proposed antenna arrays have given directional radiation patterns, very small voltage standing wave ratio, high gain (VSWR) and directivity for each aforementioned systems operating frequency. This antenna is made for multiband purpose which can be effective for not only Wi-Fi and WiMAX but also 5G applications.

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In the 1960s, earthen embankments, locally known as polders, were first constructed in the Ganges–Brahmaputra–Meghna (GBM) Delta with the intention of protecting agricultural lands from salinity; however, unintended consequences of the barriers have negatively impacted the region. Once‐active distributary channels have morphed into terminal, headless tidal channels as the sediment‐laden water that was once dispersed across the tidal delta plain is now restricted by embankments. Elevation loss within embankments and channel siltation adjacent to embankments are deleterious consequences of hard engineering and pose significant flood risk when effective sea level rise is considered. The purpose of this study is to assess the current and future flood risks of the embanked areas in the southwest region of the GBM Delta and to expand on the potential for local‐based solutions (e.g. mud plinths and embankments). We propose a novel source of material for these structures—repurposed dredge spoils. Project sites are along terminal tidal channels, proximal to coastal towns in the southwest region of the delta. We calculate here that as the effective sea level rise will continue to increase in the years to come, the flood risk will correspondingly increase (>67%). Geospatial analyses reveal that several prominent tidal channels have reduced in width over the last 30+ years, and recent dredging operations removed ~1.7 × 106 m3 of sediment infill. Using conservative values, we estimate that the dredge spoils could be used to elevate ~20 000 houses on mud plinths or raise 18 km of existing embankments. On a delta‐wide scale, if all infilled tidal channels were dredged to 10% of their original widths, ~547 000 houses could be raised above the flood levels and ~500 km of embankments could be elevated. With a mean household population of 4.3 people, repurposing dredge spoils can positively impact ~2.4 million people within the vulnerable southwest region of the GBM Delta.